Merge branch 'support/3.2' into develop

lib/symfony/mime/Address.php

@@ -0,0 +1,120 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Egulias\EmailValidator\EmailValidator;
+use Egulias\EmailValidator\Validation\MessageIDValidation;
+use Egulias\EmailValidator\Validation\RFCValidation;
+use Symfony\Component\Mime\Encoder\IdnAddressEncoder;
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Exception\LogicException;
+use Symfony\Component\Mime\Exception\RfcComplianceException;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class Address
+{
+    /**
+     * A regex that matches a structure like 'Name <email@address.com>'.
+     * It matches anything between the first < and last > as email address.
+     * This allows to use a single string to construct an Address, which can be convenient to use in
+     * config, and allows to have more readable config.
+     * This does not try to cover all edge cases for address.
+     */
+    private const FROM_STRING_PATTERN = '~(?<displayName>[^<]*)<(?<addrSpec>.*)>[^>]*~';
+
+    private static EmailValidator $validator;
+    private static IdnAddressEncoder $encoder;
+
+    private string $address;
+    private string $name;
+
+    public function __construct(string $address, string $name = '')
+    {
+        if (!class_exists(EmailValidator::class)) {
+            throw new LogicException(\sprintf('The "%s" class cannot be used as it needs "%s". Try running "composer require egulias/email-validator".', __CLASS__, EmailValidator::class));
+        }
+
+        self::$validator ??= new EmailValidator();
+
+        $this->address = trim($address);
+        $this->name = trim(str_replace(["\n", "\r"], '', $name));
+
+        if (!self::$validator->isValid($this->address, class_exists(MessageIDValidation::class) ? new MessageIDValidation() : new RFCValidation())) {
+            throw new RfcComplianceException(\sprintf('Email "%s" does not comply with addr-spec of RFC 2822.', $address));
+        }
+    }
+
+    public function getAddress(): string
+    {
+        return $this->address;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function getEncodedAddress(): string
+    {
+        self::$encoder ??= new IdnAddressEncoder();
+
+        return self::$encoder->encodeString($this->address);
+    }
+
+    public function toString(): string
+    {
+        return ($n = $this->getEncodedName()) ? $n.' <'.$this->getEncodedAddress().'>' : $this->getEncodedAddress();
+    }
+
+    public function getEncodedName(): string
+    {
+        if ('' === $this->getName()) {
+            return '';
+        }
+
+        return \sprintf('"%s"', preg_replace('/"/u', '\"', $this->getName()));
+    }
+
+    public static function create(self|string $address): self
+    {
+        if ($address instanceof self) {
+            return $address;
+        }
+
+        if (!str_contains($address, '<')) {
+            return new self($address);
+        }
+
+        if (!preg_match(self::FROM_STRING_PATTERN, $address, $matches)) {
+            throw new InvalidArgumentException(\sprintf('Could not parse "%s" to a "%s" instance.', $address, self::class));
+        }
+
+        return new self($matches['addrSpec'], trim($matches['displayName'], ' \'"'));
+    }
+
+    /**
+     * @param array<Address|string> $addresses
+     *
+     * @return Address[]
+     */
+    public static function createArray(array $addresses): array
+    {
+        $addrs = [];
+        foreach ($addresses as $address) {
+            $addrs[] = self::create($address);
+        }
+
+        return $addrs;
+    }
+}

lib/symfony/mime/BodyRendererInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface BodyRendererInterface
+{
+    public function render(Message $message): void;
+}

lib/symfony/mime/CHANGELOG.md

@@ -0,0 +1,50 @@
+CHANGELOG
+=========
+
+6.3
+---
+
+ * Support detection of related parts if `Content-Id` is used instead of the name
+ * Add `TextPart::getDisposition()`
+
+6.2
+---
+
+ * Add `File`
+ * Deprecate `Email::attachPart()`, use `addPart()` instead
+ * Deprecate calling `Message::setBody()` without arguments
+
+6.1
+---
+
+ * Add `DataPart::getFilename()` and `DataPart::getContentType()`
+
+6.0
+---
+
+ * Remove `Address::fromString()`, use `Address::create()` instead
+ * Remove `Serializable` interface from `RawMessage`
+
+5.2.0
+-----
+
+ * Add support for DKIM
+ * Deprecated `Address::fromString()`, use `Address::create()` instead
+
+4.4.0
+-----
+
+ * [BC BREAK] Removed `NamedAddress` (`Address` now supports a name)
+ * Added PHPUnit constraints
+ * Added `AbstractPart::asDebugString()`
+ * Added `Address::fromString()`
+
+4.3.3
+-----
+
+ * [BC BREAK] Renamed method `Headers::getAll()` to `Headers::all()`.
+
+4.3.0
+-----
+
+ * Introduced the component as experimental

lib/symfony/mime/CharacterStream.php

@@ -0,0 +1,211 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ * @author Xavier De Cock <xdecock@gmail.com>
+ *
+ * @internal
+ */
+final class CharacterStream
+{
+    /** Pre-computed for optimization */
+    private const UTF8_LENGTH_MAP = [
+        "\x00" => 1, "\x01" => 1, "\x02" => 1, "\x03" => 1, "\x04" => 1, "\x05" => 1, "\x06" => 1, "\x07" => 1,
+        "\x08" => 1, "\x09" => 1, "\x0a" => 1, "\x0b" => 1, "\x0c" => 1, "\x0d" => 1, "\x0e" => 1, "\x0f" => 1,
+        "\x10" => 1, "\x11" => 1, "\x12" => 1, "\x13" => 1, "\x14" => 1, "\x15" => 1, "\x16" => 1, "\x17" => 1,
+        "\x18" => 1, "\x19" => 1, "\x1a" => 1, "\x1b" => 1, "\x1c" => 1, "\x1d" => 1, "\x1e" => 1, "\x1f" => 1,
+        "\x20" => 1, "\x21" => 1, "\x22" => 1, "\x23" => 1, "\x24" => 1, "\x25" => 1, "\x26" => 1, "\x27" => 1,
+        "\x28" => 1, "\x29" => 1, "\x2a" => 1, "\x2b" => 1, "\x2c" => 1, "\x2d" => 1, "\x2e" => 1, "\x2f" => 1,
+        "\x30" => 1, "\x31" => 1, "\x32" => 1, "\x33" => 1, "\x34" => 1, "\x35" => 1, "\x36" => 1, "\x37" => 1,
+        "\x38" => 1, "\x39" => 1, "\x3a" => 1, "\x3b" => 1, "\x3c" => 1, "\x3d" => 1, "\x3e" => 1, "\x3f" => 1,
+        "\x40" => 1, "\x41" => 1, "\x42" => 1, "\x43" => 1, "\x44" => 1, "\x45" => 1, "\x46" => 1, "\x47" => 1,
+        "\x48" => 1, "\x49" => 1, "\x4a" => 1, "\x4b" => 1, "\x4c" => 1, "\x4d" => 1, "\x4e" => 1, "\x4f" => 1,
+        "\x50" => 1, "\x51" => 1, "\x52" => 1, "\x53" => 1, "\x54" => 1, "\x55" => 1, "\x56" => 1, "\x57" => 1,
+        "\x58" => 1, "\x59" => 1, "\x5a" => 1, "\x5b" => 1, "\x5c" => 1, "\x5d" => 1, "\x5e" => 1, "\x5f" => 1,
+        "\x60" => 1, "\x61" => 1, "\x62" => 1, "\x63" => 1, "\x64" => 1, "\x65" => 1, "\x66" => 1, "\x67" => 1,
+        "\x68" => 1, "\x69" => 1, "\x6a" => 1, "\x6b" => 1, "\x6c" => 1, "\x6d" => 1, "\x6e" => 1, "\x6f" => 1,
+        "\x70" => 1, "\x71" => 1, "\x72" => 1, "\x73" => 1, "\x74" => 1, "\x75" => 1, "\x76" => 1, "\x77" => 1,
+        "\x78" => 1, "\x79" => 1, "\x7a" => 1, "\x7b" => 1, "\x7c" => 1, "\x7d" => 1, "\x7e" => 1, "\x7f" => 1,
+        "\x80" => 0, "\x81" => 0, "\x82" => 0, "\x83" => 0, "\x84" => 0, "\x85" => 0, "\x86" => 0, "\x87" => 0,
+        "\x88" => 0, "\x89" => 0, "\x8a" => 0, "\x8b" => 0, "\x8c" => 0, "\x8d" => 0, "\x8e" => 0, "\x8f" => 0,
+        "\x90" => 0, "\x91" => 0, "\x92" => 0, "\x93" => 0, "\x94" => 0, "\x95" => 0, "\x96" => 0, "\x97" => 0,
+        "\x98" => 0, "\x99" => 0, "\x9a" => 0, "\x9b" => 0, "\x9c" => 0, "\x9d" => 0, "\x9e" => 0, "\x9f" => 0,
+        "\xa0" => 0, "\xa1" => 0, "\xa2" => 0, "\xa3" => 0, "\xa4" => 0, "\xa5" => 0, "\xa6" => 0, "\xa7" => 0,
+        "\xa8" => 0, "\xa9" => 0, "\xaa" => 0, "\xab" => 0, "\xac" => 0, "\xad" => 0, "\xae" => 0, "\xaf" => 0,
+        "\xb0" => 0, "\xb1" => 0, "\xb2" => 0, "\xb3" => 0, "\xb4" => 0, "\xb5" => 0, "\xb6" => 0, "\xb7" => 0,
+        "\xb8" => 0, "\xb9" => 0, "\xba" => 0, "\xbb" => 0, "\xbc" => 0, "\xbd" => 0, "\xbe" => 0, "\xbf" => 0,
+        "\xc0" => 2, "\xc1" => 2, "\xc2" => 2, "\xc3" => 2, "\xc4" => 2, "\xc5" => 2, "\xc6" => 2, "\xc7" => 2,
+        "\xc8" => 2, "\xc9" => 2, "\xca" => 2, "\xcb" => 2, "\xcc" => 2, "\xcd" => 2, "\xce" => 2, "\xcf" => 2,
+        "\xd0" => 2, "\xd1" => 2, "\xd2" => 2, "\xd3" => 2, "\xd4" => 2, "\xd5" => 2, "\xd6" => 2, "\xd7" => 2,
+        "\xd8" => 2, "\xd9" => 2, "\xda" => 2, "\xdb" => 2, "\xdc" => 2, "\xdd" => 2, "\xde" => 2, "\xdf" => 2,
+        "\xe0" => 3, "\xe1" => 3, "\xe2" => 3, "\xe3" => 3, "\xe4" => 3, "\xe5" => 3, "\xe6" => 3, "\xe7" => 3,
+        "\xe8" => 3, "\xe9" => 3, "\xea" => 3, "\xeb" => 3, "\xec" => 3, "\xed" => 3, "\xee" => 3, "\xef" => 3,
+        "\xf0" => 4, "\xf1" => 4, "\xf2" => 4, "\xf3" => 4, "\xf4" => 4, "\xf5" => 4, "\xf6" => 4, "\xf7" => 4,
+        "\xf8" => 5, "\xf9" => 5, "\xfa" => 5, "\xfb" => 5, "\xfc" => 6, "\xfd" => 6, "\xfe" => 0, "\xff" => 0,
+    ];
+
+    private string $data = '';
+    private int $dataSize = 0;
+    private array $map = [];
+    private int $charCount = 0;
+    private int $currentPos = 0;
+    private int $fixedWidth = 0;
+
+    /**
+     * @param resource|string $input
+     */
+    public function __construct($input, ?string $charset = 'utf-8')
+    {
+        $charset = strtolower(trim($charset)) ?: 'utf-8';
+        if ('utf-8' === $charset || 'utf8' === $charset) {
+            $this->fixedWidth = 0;
+            $this->map = ['p' => [], 'i' => []];
+        } else {
+            $this->fixedWidth = match ($charset) {
+                // 16 bits
+                'ucs2',
+                'ucs-2',
+                'utf16',
+                'utf-16' => 2,
+                // 32 bits
+                'ucs4',
+                'ucs-4',
+                'utf32',
+                'utf-32' => 4,
+                // 7-8 bit charsets: (us-)?ascii, (iso|iec)-?8859-?[0-9]+, windows-?125[0-9], cp-?[0-9]+, ansi, macintosh,
+                //                   koi-?7, koi-?8-?.+, mik, (cork|t1), v?iscii
+                // and fallback
+                default => 1,
+            };
+        }
+        if (\is_resource($input)) {
+            $blocks = 16372;
+            while (false !== $read = fread($input, $blocks)) {
+                $this->write($read);
+            }
+        } else {
+            $this->write($input);
+        }
+    }
+
+    public function read(int $length): ?string
+    {
+        if ($this->currentPos >= $this->charCount) {
+            return null;
+        }
+        $length = ($this->currentPos + $length > $this->charCount) ? $this->charCount - $this->currentPos : $length;
+        if ($this->fixedWidth > 0) {
+            $len = $length * $this->fixedWidth;
+            $ret = substr($this->data, $this->currentPos * $this->fixedWidth, $len);
+            $this->currentPos += $length;
+        } else {
+            $end = $this->currentPos + $length;
+            $end = $end > $this->charCount ? $this->charCount : $end;
+            $ret = '';
+            $start = 0;
+            if ($this->currentPos > 0) {
+                $start = $this->map['p'][$this->currentPos - 1];
+            }
+            $to = $start;
+            for (; $this->currentPos < $end; ++$this->currentPos) {
+                if (isset($this->map['i'][$this->currentPos])) {
+                    $ret .= substr($this->data, $start, $to - $start).'?';
+                    $start = $this->map['p'][$this->currentPos];
+                } else {
+                    $to = $this->map['p'][$this->currentPos];
+                }
+            }
+            $ret .= substr($this->data, $start, $to - $start);
+        }
+
+        return $ret;
+    }
+
+    public function readBytes(int $length): ?array
+    {
+        if (null !== $read = $this->read($length)) {
+            return array_map('ord', str_split($read, 1));
+        }
+
+        return null;
+    }
+
+    public function setPointer(int $charOffset): void
+    {
+        if ($this->charCount < $charOffset) {
+            $charOffset = $this->charCount;
+        }
+        $this->currentPos = $charOffset;
+    }
+
+    public function write(string $chars): void
+    {
+        $ignored = '';
+        $this->data .= $chars;
+        if ($this->fixedWidth > 0) {
+            $strlen = \strlen($chars);
+            $ignoredL = $strlen % $this->fixedWidth;
+            $ignored = $ignoredL ? substr($chars, -$ignoredL) : '';
+            $this->charCount += ($strlen - $ignoredL) / $this->fixedWidth;
+        } else {
+            $this->charCount += $this->getUtf8CharPositions($chars, $this->dataSize, $ignored);
+        }
+        $this->dataSize = \strlen($this->data) - \strlen($ignored);
+    }
+
+    private function getUtf8CharPositions(string $string, int $startOffset, string &$ignoredChars): int
+    {
+        $strlen = \strlen($string);
+        $charPos = \count($this->map['p']);
+        $foundChars = 0;
+        $invalid = false;
+        for ($i = 0; $i < $strlen; ++$i) {
+            $char = $string[$i];
+            $size = self::UTF8_LENGTH_MAP[$char];
+            if (0 == $size) {
+                /* char is invalid, we must wait for a resync */
+                $invalid = true;
+                continue;
+            }
+
+            if ($invalid) {
+                /* We mark the chars as invalid and start a new char */
+                $this->map['p'][$charPos + $foundChars] = $startOffset + $i;
+                $this->map['i'][$charPos + $foundChars] = true;
+                ++$foundChars;
+                $invalid = false;
+            }
+            if (($i + $size) > $strlen) {
+                $ignoredChars = substr($string, $i);
+                break;
+            }
+            for ($j = 1; $j < $size; ++$j) {
+                $char = $string[$i + $j];
+                if ($char > "\x7F" && $char < "\xC0") {
+                    // Valid - continue parsing
+                } else {
+                    /* char is invalid, we must wait for a resync */
+                    $invalid = true;
+                    continue 2;
+                }
+            }
+            /* Ok we got a complete char here */
+            $this->map['p'][$charPos + $foundChars] = $startOffset + $i + $size;
+            $i += $j - 1;
+            ++$foundChars;
+        }
+
+        return $foundChars;
+    }
+}

lib/symfony/mime/Crypto/DkimOptions.php

@@ -0,0 +1,97 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Crypto;
+
+/**
+ * A helper providing autocompletion for available DkimSigner options.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class DkimOptions
+{
+    private array $options = [];
+
+    public function toArray(): array
+    {
+        return $this->options;
+    }
+
+    /**
+     * @return $this
+     */
+    public function algorithm(string $algo): static
+    {
+        $this->options['algorithm'] = $algo;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function signatureExpirationDelay(int $show): static
+    {
+        $this->options['signature_expiration_delay'] = $show;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function bodyMaxLength(int $max): static
+    {
+        $this->options['body_max_length'] = $max;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function bodyShowLength(bool $show): static
+    {
+        $this->options['body_show_length'] = $show;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function headerCanon(string $canon): static
+    {
+        $this->options['header_canon'] = $canon;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function bodyCanon(string $canon): static
+    {
+        $this->options['body_canon'] = $canon;
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    public function headersToIgnore(array $headers): static
+    {
+        $this->options['headers_to_ignore'] = $headers;
+
+        return $this;
+    }
+}

lib/symfony/mime/Crypto/DkimSigner.php

@@ -0,0 +1,217 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Crypto;
+
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Exception\RuntimeException;
+use Symfony\Component\Mime\Header\UnstructuredHeader;
+use Symfony\Component\Mime\Message;
+use Symfony\Component\Mime\Part\AbstractPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * RFC 6376 and 8301
+ */
+final class DkimSigner
+{
+    public const CANON_SIMPLE = 'simple';
+    public const CANON_RELAXED = 'relaxed';
+
+    public const ALGO_SHA256 = 'rsa-sha256';
+    public const ALGO_ED25519 = 'ed25519-sha256'; // RFC 8463
+
+    private \OpenSSLAsymmetricKey $key;
+    private string $domainName;
+    private string $selector;
+    private array $defaultOptions;
+
+    /**
+     * @param string $pk         The private key as a string or the path to the file containing the private key, should be prefixed with file:// (in PEM format)
+     * @param string $passphrase A passphrase of the private key (if any)
+     */
+    public function __construct(string $pk, string $domainName, string $selector, array $defaultOptions = [], string $passphrase = '')
+    {
+        if (!\extension_loaded('openssl')) {
+            throw new \LogicException('PHP extension "openssl" is required to use DKIM.');
+        }
+        $this->key = openssl_pkey_get_private($pk, $passphrase) ?: throw new InvalidArgumentException('Unable to load DKIM private key: '.openssl_error_string());
+        $this->domainName = $domainName;
+        $this->selector = $selector;
+        $this->defaultOptions = $defaultOptions + [
+            'algorithm' => self::ALGO_SHA256,
+            'signature_expiration_delay' => 0,
+            'body_max_length' => \PHP_INT_MAX,
+            'body_show_length' => false,
+            'header_canon' => self::CANON_RELAXED,
+            'body_canon' => self::CANON_RELAXED,
+            'headers_to_ignore' => [],
+        ];
+    }
+
+    public function sign(Message $message, array $options = []): Message
+    {
+        $options += $this->defaultOptions;
+        if (!\in_array($options['algorithm'], [self::ALGO_SHA256, self::ALGO_ED25519], true)) {
+            throw new InvalidArgumentException(\sprintf('Invalid DKIM signing algorithm "%s".', $options['algorithm']));
+        }
+        $headersToIgnore['return-path'] = true;
+        $headersToIgnore['x-transport'] = true;
+        foreach ($options['headers_to_ignore'] as $name) {
+            $headersToIgnore[strtolower($name)] = true;
+        }
+        unset($headersToIgnore['from']);
+        $signedHeaderNames = [];
+        $headerCanonData = '';
+        $headers = $message->getPreparedHeaders();
+        foreach ($headers->getNames() as $name) {
+            foreach ($headers->all($name) as $header) {
+                if (isset($headersToIgnore[strtolower($header->getName())])) {
+                    continue;
+                }
+
+                if ('' !== $header->getBodyAsString()) {
+                    $headerCanonData .= $this->canonicalizeHeader($header->toString(), $options['header_canon']);
+                    $signedHeaderNames[] = $header->getName();
+                }
+            }
+        }
+
+        [$bodyHash, $bodyLength] = $this->hashBody($message->getBody(), $options['body_canon'], $options['body_max_length']);
+
+        $params = [
+            'v' => '1',
+            'q' => 'dns/txt',
+            'a' => $options['algorithm'],
+            'bh' => base64_encode($bodyHash),
+            'd' => $this->domainName,
+            'h' => implode(': ', $signedHeaderNames),
+            'i' => '@'.$this->domainName,
+            's' => $this->selector,
+            't' => time(),
+            'c' => $options['header_canon'].'/'.$options['body_canon'],
+        ];
+
+        if ($options['body_show_length']) {
+            $params['l'] = $bodyLength;
+        }
+        if ($options['signature_expiration_delay']) {
+            $params['x'] = $params['t'] + $options['signature_expiration_delay'];
+        }
+        $value = '';
+        foreach ($params as $k => $v) {
+            $value .= $k.'='.$v.'; ';
+        }
+        $value = trim($value);
+        $header = new UnstructuredHeader('DKIM-Signature', $value);
+        $headerCanonData .= rtrim($this->canonicalizeHeader($header->toString()."\r\n b=", $options['header_canon']));
+        if (self::ALGO_SHA256 === $options['algorithm']) {
+            if (!openssl_sign($headerCanonData, $signature, $this->key, \OPENSSL_ALGO_SHA256)) {
+                throw new RuntimeException('Unable to sign DKIM hash: '.openssl_error_string());
+            }
+        } else {
+            throw new \RuntimeException(\sprintf('The "%s" DKIM signing algorithm is not supported yet.', self::ALGO_ED25519));
+        }
+        $header->setValue($value.' b='.trim(chunk_split(base64_encode($signature), 73, ' ')));
+        $headers->add($header);
+
+        return new Message($headers, $message->getBody());
+    }
+
+    private function canonicalizeHeader(string $header, string $headerCanon): string
+    {
+        if (self::CANON_RELAXED !== $headerCanon) {
+            return $header."\r\n";
+        }
+
+        $exploded = explode(':', $header, 2);
+        $name = strtolower(trim($exploded[0]));
+        $value = str_replace("\r\n", '', $exploded[1]);
+        $value = trim(preg_replace("/[ \t][ \t]+/", ' ', $value));
+
+        return $name.':'.$value."\r\n";
+    }
+
+    private function hashBody(AbstractPart $body, string $bodyCanon, int $maxLength): array
+    {
+        $hash = hash_init('sha256');
+        $relaxed = self::CANON_RELAXED === $bodyCanon;
+        $currentLine = '';
+        $emptyCounter = 0;
+        $isSpaceSequence = false;
+        $length = 0;
+        foreach ($body->bodyToIterable() as $chunk) {
+            $canon = '';
+            for ($i = 0, $len = \strlen($chunk); $i < $len; ++$i) {
+                switch ($chunk[$i]) {
+                    case "\r":
+                        break;
+                    case "\n":
+                        // previous char is always \r
+                        if ($relaxed) {
+                            $isSpaceSequence = false;
+                        }
+                        if ('' === $currentLine) {
+                            ++$emptyCounter;
+                        } else {
+                            $currentLine = '';
+                            $canon .= "\r\n";
+                        }
+                        break;
+                    case ' ':
+                    case "\t":
+                        if ($relaxed) {
+                            $isSpaceSequence = true;
+                            break;
+                        }
+                        // no break
+                    default:
+                        if ($emptyCounter > 0) {
+                            $canon .= str_repeat("\r\n", $emptyCounter);
+                            $emptyCounter = 0;
+                        }
+                        if ($isSpaceSequence) {
+                            $currentLine .= ' ';
+                            $canon .= ' ';
+                            $isSpaceSequence = false;
+                        }
+                        $currentLine .= $chunk[$i];
+                        $canon .= $chunk[$i];
+                }
+            }
+
+            if ($length + \strlen($canon) >= $maxLength) {
+                $canon = substr($canon, 0, $maxLength - $length);
+                $length += \strlen($canon);
+                hash_update($hash, $canon);
+
+                break;
+            }
+
+            $length += \strlen($canon);
+            hash_update($hash, $canon);
+        }
+
+        // Add trailing Line return if last line is non empty
+        if ('' !== $currentLine) {
+            hash_update($hash, "\r\n");
+            $length += \strlen("\r\n");
+        }
+
+        if (!$relaxed && 0 === $length) {
+            hash_update($hash, "\r\n");
+            $length = 2;
+        }
+
+        return [hash_final($hash, true), $length];
+    }
+}

lib/symfony/mime/Crypto/SMime.php

@@ -0,0 +1,111 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Crypto;
+
+use Symfony\Component\Mime\Exception\RuntimeException;
+use Symfony\Component\Mime\Part\SMimePart;
+
+/**
+ * @author Sebastiaan Stok <s.stok@rollerscapes.net>
+ *
+ * @internal
+ */
+abstract class SMime
+{
+    protected function normalizeFilePath(string $path): string
+    {
+        if (!file_exists($path)) {
+            throw new RuntimeException(\sprintf('File does not exist: "%s".', $path));
+        }
+
+        return 'file://'.str_replace('\\', '/', realpath($path));
+    }
+
+    protected function iteratorToFile(iterable $iterator, $stream): void
+    {
+        foreach ($iterator as $chunk) {
+            fwrite($stream, $chunk);
+        }
+    }
+
+    protected function convertMessageToSMimePart($stream, string $type, string $subtype): SMimePart
+    {
+        rewind($stream);
+
+        $headers = '';
+
+        while (!feof($stream)) {
+            $buffer = fread($stream, 78);
+            $headers .= $buffer;
+
+            // Detect ending of header list
+            if (preg_match('/(\r\n\r\n|\n\n)/', $headers, $match)) {
+                $headersPosEnd = strpos($headers, $headerBodySeparator = $match[0]);
+
+                break;
+            }
+        }
+
+        $headers = $this->getMessageHeaders(trim(substr($headers, 0, $headersPosEnd)));
+
+        fseek($stream, $headersPosEnd + \strlen($headerBodySeparator));
+
+        return new SMimePart($this->getStreamIterator($stream), $type, $subtype, $this->getParametersFromHeader($headers['content-type']));
+    }
+
+    protected function getStreamIterator($stream): iterable
+    {
+        while (!feof($stream)) {
+            yield str_replace("\n", "\r\n", str_replace("\r\n", "\n", fread($stream, 16372)));
+        }
+    }
+
+    private function getMessageHeaders(string $headerData): array
+    {
+        $headers = [];
+        $headerLines = explode("\r\n", str_replace("\n", "\r\n", str_replace("\r\n", "\n", $headerData)));
+        $currentHeaderName = '';
+
+        // Transform header lines into an associative array
+        foreach ($headerLines as $headerLine) {
+            // Empty lines between headers indicate a new mime-entity
+            if ('' === $headerLine) {
+                break;
+            }
+
+            // Handle headers that span multiple lines
+            if (!str_contains($headerLine, ':')) {
+                $headers[$currentHeaderName] .= ' '.trim($headerLine);
+                continue;
+            }
+
+            $header = explode(':', $headerLine, 2);
+            $currentHeaderName = strtolower($header[0]);
+            $headers[$currentHeaderName] = trim($header[1]);
+        }
+
+        return $headers;
+    }
+
+    private function getParametersFromHeader(string $header): array
+    {
+        $params = [];
+
+        preg_match_all('/(?P<name>[a-z-0-9]+)=(?P<value>"[^"]+"|(?:[^\s;]+|$))(?:\s+;)?/i', $header, $matches);
+
+        foreach ($matches['value'] as $pos => $paramValue) {
+            $params[$matches['name'][$pos]] = trim($paramValue, '"');
+        }
+
+        return $params;
+    }
+}

lib/symfony/mime/Crypto/SMimeEncrypter.php

@@ -0,0 +1,63 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Crypto;
+
+use Symfony\Component\Mime\Exception\RuntimeException;
+use Symfony\Component\Mime\Message;
+
+/**
+ * @author Sebastiaan Stok <s.stok@rollerscapes.net>
+ */
+final class SMimeEncrypter extends SMime
+{
+    private string|array $certs;
+    private int $cipher;
+
+    /**
+     * @param string|string[] $certificate The path (or array of paths) of the file(s) containing the X.509 certificate(s)
+     * @param int|null        $cipher      A set of algorithms used to encrypt the message. Must be one of these PHP constants: https://php.net/openssl.ciphers
+     */
+    public function __construct(string|array $certificate, ?int $cipher = null)
+    {
+        if (!\extension_loaded('openssl')) {
+            throw new \LogicException('PHP extension "openssl" is required to use SMime.');
+        }
+
+        if (\is_array($certificate)) {
+            $this->certs = array_map($this->normalizeFilePath(...), $certificate);
+        } else {
+            $this->certs = $this->normalizeFilePath($certificate);
+        }
+
+        $this->cipher = $cipher ?? \OPENSSL_CIPHER_AES_256_CBC;
+    }
+
+    public function encrypt(Message $message): Message
+    {
+        $bufferFile = tmpfile();
+        $outputFile = tmpfile();
+
+        $this->iteratorToFile($message->toIterable(), $bufferFile);
+
+        if (!@openssl_pkcs7_encrypt(stream_get_meta_data($bufferFile)['uri'], stream_get_meta_data($outputFile)['uri'], $this->certs, [], 0, $this->cipher)) {
+            throw new RuntimeException(\sprintf('Failed to encrypt S/Mime message. Error: "%s".', openssl_error_string()));
+        }
+
+        $mimePart = $this->convertMessageToSMimePart($outputFile, 'application', 'pkcs7-mime');
+        $mimePart->getHeaders()
+            ->addTextHeader('Content-Transfer-Encoding', 'base64')
+            ->addParameterizedHeader('Content-Disposition', 'attachment', ['name' => 'smime.p7m'])
+        ;
+
+        return new Message($message->getHeaders(), $mimePart);
+    }
+}

lib/symfony/mime/Crypto/SMimeSigner.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Crypto;
+
+use Symfony\Component\Mime\Exception\RuntimeException;
+use Symfony\Component\Mime\Message;
+
+/**
+ * @author Sebastiaan Stok <s.stok@rollerscapes.net>
+ */
+final class SMimeSigner extends SMime
+{
+    private string $signCertificate;
+    private string|array $signPrivateKey;
+    private int $signOptions;
+    private ?string $extraCerts;
+
+    /**
+     * @param string      $certificate          The path of the file containing the signing certificate (in PEM format)
+     * @param string      $privateKey           The path of the file containing the private key (in PEM format)
+     * @param string|null $privateKeyPassphrase A passphrase of the private key (if any)
+     * @param string|null $extraCerts           The path of the file containing intermediate certificates (in PEM format) needed by the signing certificate
+     * @param int|null    $signOptions          Bitwise operator options for openssl_pkcs7_sign() (@see https://secure.php.net/manual/en/openssl.pkcs7.flags.php)
+     */
+    public function __construct(string $certificate, string $privateKey, ?string $privateKeyPassphrase = null, ?string $extraCerts = null, ?int $signOptions = null)
+    {
+        if (!\extension_loaded('openssl')) {
+            throw new \LogicException('PHP extension "openssl" is required to use SMime.');
+        }
+
+        $this->signCertificate = $this->normalizeFilePath($certificate);
+
+        if (null !== $privateKeyPassphrase) {
+            $this->signPrivateKey = [$this->normalizeFilePath($privateKey), $privateKeyPassphrase];
+        } else {
+            $this->signPrivateKey = $this->normalizeFilePath($privateKey);
+        }
+
+        $this->signOptions = $signOptions ?? \PKCS7_DETACHED;
+        $this->extraCerts = $extraCerts ? realpath($extraCerts) : null;
+    }
+
+    public function sign(Message $message): Message
+    {
+        $bufferFile = tmpfile();
+        $outputFile = tmpfile();
+
+        $this->iteratorToFile($message->getBody()->toIterable(), $bufferFile);
+
+        if (!@openssl_pkcs7_sign(stream_get_meta_data($bufferFile)['uri'], stream_get_meta_data($outputFile)['uri'], $this->signCertificate, $this->signPrivateKey, [], $this->signOptions, $this->extraCerts)) {
+            throw new RuntimeException(\sprintf('Failed to sign S/Mime message. Error: "%s".', openssl_error_string()));
+        }
+
+        return new Message($message->getHeaders(), $this->convertMessageToSMimePart($outputFile, 'multipart', 'signed'));
+    }
+}

lib/symfony/mime/DependencyInjection/AddMimeTypeGuesserPass.php

@@ -0,0 +1,37 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\DependencyInjection;
+
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Reference;
+
+/**
+ * Registers custom mime types guessers.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class AddMimeTypeGuesserPass implements CompilerPassInterface
+{
+    /**
+     * @return void
+     */
+    public function process(ContainerBuilder $container)
+    {
+        if ($container->has('mime_types')) {
+            $definition = $container->findDefinition('mime_types');
+            foreach ($container->findTaggedServiceIds('mime.mime_type_guesser', true) as $id => $attributes) {
+                $definition->addMethodCall('registerGuesser', [new Reference($id)]);
+            }
+        }
+    }
+}

lib/symfony/mime/DraftEmail.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Header\Headers;
+use Symfony\Component\Mime\Part\AbstractPart;
+
+/**
+ * @author Kevin Bond <kevinbond@gmail.com>
+ */
+class DraftEmail extends Email
+{
+    public function __construct(?Headers $headers = null, ?AbstractPart $body = null)
+    {
+        parent::__construct($headers, $body);
+
+        $this->getHeaders()->addTextHeader('X-Unsent', '1');
+    }
+
+    /**
+     * Override default behavior as draft emails do not require From/Sender/Date/Message-ID headers.
+     * These are added by the client that actually sends the email.
+     */
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = clone $this->getHeaders();
+
+        if (!$headers->has('MIME-Version')) {
+            $headers->addTextHeader('MIME-Version', '1.0');
+        }
+
+        $headers->remove('Bcc');
+
+        return $headers;
+    }
+}

lib/symfony/mime/Email.php

@@ -0,0 +1,591 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\LogicException;
+use Symfony\Component\Mime\Part\AbstractPart;
+use Symfony\Component\Mime\Part\DataPart;
+use Symfony\Component\Mime\Part\File;
+use Symfony\Component\Mime\Part\Multipart\AlternativePart;
+use Symfony\Component\Mime\Part\Multipart\MixedPart;
+use Symfony\Component\Mime\Part\Multipart\RelatedPart;
+use Symfony\Component\Mime\Part\TextPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Email extends Message
+{
+    public const PRIORITY_HIGHEST = 1;
+    public const PRIORITY_HIGH = 2;
+    public const PRIORITY_NORMAL = 3;
+    public const PRIORITY_LOW = 4;
+    public const PRIORITY_LOWEST = 5;
+
+    private const PRIORITY_MAP = [
+        self::PRIORITY_HIGHEST => 'Highest',
+        self::PRIORITY_HIGH => 'High',
+        self::PRIORITY_NORMAL => 'Normal',
+        self::PRIORITY_LOW => 'Low',
+        self::PRIORITY_LOWEST => 'Lowest',
+    ];
+
+    /**
+     * @var resource|string|null
+     */
+    private $text;
+
+    private ?string $textCharset = null;
+
+    /**
+     * @var resource|string|null
+     */
+    private $html;
+
+    private ?string $htmlCharset = null;
+    private array $attachments = [];
+    private ?AbstractPart $cachedBody = null; // Used to avoid wrong body hash in DKIM signatures with multiple parts (e.g. HTML + TEXT) due to multiple boundaries.
+
+    /**
+     * @return $this
+     */
+    public function subject(string $subject): static
+    {
+        return $this->setHeaderBody('Text', 'Subject', $subject);
+    }
+
+    public function getSubject(): ?string
+    {
+        return $this->getHeaders()->getHeaderBody('Subject');
+    }
+
+    /**
+     * @return $this
+     */
+    public function date(\DateTimeInterface $dateTime): static
+    {
+        return $this->setHeaderBody('Date', 'Date', $dateTime);
+    }
+
+    public function getDate(): ?\DateTimeImmutable
+    {
+        return $this->getHeaders()->getHeaderBody('Date');
+    }
+
+    /**
+     * @return $this
+     */
+    public function returnPath(Address|string $address): static
+    {
+        return $this->setHeaderBody('Path', 'Return-Path', Address::create($address));
+    }
+
+    public function getReturnPath(): ?Address
+    {
+        return $this->getHeaders()->getHeaderBody('Return-Path');
+    }
+
+    /**
+     * @return $this
+     */
+    public function sender(Address|string $address): static
+    {
+        return $this->setHeaderBody('Mailbox', 'Sender', Address::create($address));
+    }
+
+    public function getSender(): ?Address
+    {
+        return $this->getHeaders()->getHeaderBody('Sender');
+    }
+
+    /**
+     * @return $this
+     */
+    public function addFrom(Address|string ...$addresses): static
+    {
+        return $this->addListAddressHeaderBody('From', $addresses);
+    }
+
+    /**
+     * @return $this
+     */
+    public function from(Address|string ...$addresses): static
+    {
+        if (!$addresses) {
+            throw new LogicException('"from()" must be called with at least one address.');
+        }
+
+        return $this->setListAddressHeaderBody('From', $addresses);
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getFrom(): array
+    {
+        return $this->getHeaders()->getHeaderBody('From') ?: [];
+    }
+
+    /**
+     * @return $this
+     */
+    public function addReplyTo(Address|string ...$addresses): static
+    {
+        return $this->addListAddressHeaderBody('Reply-To', $addresses);
+    }
+
+    /**
+     * @return $this
+     */
+    public function replyTo(Address|string ...$addresses): static
+    {
+        return $this->setListAddressHeaderBody('Reply-To', $addresses);
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getReplyTo(): array
+    {
+        return $this->getHeaders()->getHeaderBody('Reply-To') ?: [];
+    }
+
+    /**
+     * @return $this
+     */
+    public function addTo(Address|string ...$addresses): static
+    {
+        return $this->addListAddressHeaderBody('To', $addresses);
+    }
+
+    /**
+     * @return $this
+     */
+    public function to(Address|string ...$addresses): static
+    {
+        return $this->setListAddressHeaderBody('To', $addresses);
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getTo(): array
+    {
+        return $this->getHeaders()->getHeaderBody('To') ?: [];
+    }
+
+    /**
+     * @return $this
+     */
+    public function addCc(Address|string ...$addresses): static
+    {
+        return $this->addListAddressHeaderBody('Cc', $addresses);
+    }
+
+    /**
+     * @return $this
+     */
+    public function cc(Address|string ...$addresses): static
+    {
+        return $this->setListAddressHeaderBody('Cc', $addresses);
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getCc(): array
+    {
+        return $this->getHeaders()->getHeaderBody('Cc') ?: [];
+    }
+
+    /**
+     * @return $this
+     */
+    public function addBcc(Address|string ...$addresses): static
+    {
+        return $this->addListAddressHeaderBody('Bcc', $addresses);
+    }
+
+    /**
+     * @return $this
+     */
+    public function bcc(Address|string ...$addresses): static
+    {
+        return $this->setListAddressHeaderBody('Bcc', $addresses);
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getBcc(): array
+    {
+        return $this->getHeaders()->getHeaderBody('Bcc') ?: [];
+    }
+
+    /**
+     * Sets the priority of this message.
+     *
+     * The value is an integer where 1 is the highest priority and 5 is the lowest.
+     *
+     * @return $this
+     */
+    public function priority(int $priority): static
+    {
+        if ($priority > 5) {
+            $priority = 5;
+        } elseif ($priority < 1) {
+            $priority = 1;
+        }
+
+        return $this->setHeaderBody('Text', 'X-Priority', \sprintf('%d (%s)', $priority, self::PRIORITY_MAP[$priority]));
+    }
+
+    /**
+     * Get the priority of this message.
+     *
+     * The returned value is an integer where 1 is the highest priority and 5
+     * is the lowest.
+     */
+    public function getPriority(): int
+    {
+        [$priority] = sscanf($this->getHeaders()->getHeaderBody('X-Priority') ?? '', '%[1-5]');
+
+        return $priority ?? 3;
+    }
+
+    /**
+     * @param resource|string|null $body
+     *
+     * @return $this
+     */
+    public function text($body, string $charset = 'utf-8'): static
+    {
+        if (null !== $body && !\is_string($body) && !\is_resource($body)) {
+            throw new \TypeError(\sprintf('The body must be a string, a resource or null (got "%s").', get_debug_type($body)));
+        }
+
+        $this->cachedBody = null;
+        $this->text = $body;
+        $this->textCharset = $charset;
+
+        return $this;
+    }
+
+    /**
+     * @return resource|string|null
+     */
+    public function getTextBody()
+    {
+        return $this->text;
+    }
+
+    public function getTextCharset(): ?string
+    {
+        return $this->textCharset;
+    }
+
+    /**
+     * @param resource|string|null $body
+     *
+     * @return $this
+     */
+    public function html($body, string $charset = 'utf-8'): static
+    {
+        if (null !== $body && !\is_string($body) && !\is_resource($body)) {
+            throw new \TypeError(\sprintf('The body must be a string, a resource or null (got "%s").', get_debug_type($body)));
+        }
+
+        $this->cachedBody = null;
+        $this->html = $body;
+        $this->htmlCharset = $charset;
+
+        return $this;
+    }
+
+    /**
+     * @return resource|string|null
+     */
+    public function getHtmlBody()
+    {
+        return $this->html;
+    }
+
+    public function getHtmlCharset(): ?string
+    {
+        return $this->htmlCharset;
+    }
+
+    /**
+     * @param resource|string $body
+     *
+     * @return $this
+     */
+    public function attach($body, ?string $name = null, ?string $contentType = null): static
+    {
+        return $this->addPart(new DataPart($body, $name, $contentType));
+    }
+
+    /**
+     * @return $this
+     */
+    public function attachFromPath(string $path, ?string $name = null, ?string $contentType = null): static
+    {
+        return $this->addPart(new DataPart(new File($path), $name, $contentType));
+    }
+
+    /**
+     * @param resource|string $body
+     *
+     * @return $this
+     */
+    public function embed($body, ?string $name = null, ?string $contentType = null): static
+    {
+        return $this->addPart((new DataPart($body, $name, $contentType))->asInline());
+    }
+
+    /**
+     * @return $this
+     */
+    public function embedFromPath(string $path, ?string $name = null, ?string $contentType = null): static
+    {
+        return $this->addPart((new DataPart(new File($path), $name, $contentType))->asInline());
+    }
+
+    /**
+     * @return $this
+     *
+     * @deprecated since Symfony 6.2, use addPart() instead
+     */
+    public function attachPart(DataPart $part): static
+    {
+        @trigger_deprecation('symfony/mime', '6.2', 'The "%s()" method is deprecated, use "addPart()" instead.', __METHOD__);
+
+        return $this->addPart($part);
+    }
+
+    /**
+     * @return $this
+     */
+    public function addPart(DataPart $part): static
+    {
+        $this->cachedBody = null;
+        $this->attachments[] = $part;
+
+        return $this;
+    }
+
+    /**
+     * @return DataPart[]
+     */
+    public function getAttachments(): array
+    {
+        return $this->attachments;
+    }
+
+    public function getBody(): AbstractPart
+    {
+        if (null !== $body = parent::getBody()) {
+            return $body;
+        }
+
+        return $this->generateBody();
+    }
+
+    /**
+     * @return void
+     */
+    public function ensureValidity()
+    {
+        $this->ensureBodyValid();
+
+        if ('1' === $this->getHeaders()->getHeaderBody('X-Unsent')) {
+            throw new LogicException('Cannot send messages marked as "draft".');
+        }
+
+        parent::ensureValidity();
+    }
+
+    private function ensureBodyValid(): void
+    {
+        if (null === $this->text && null === $this->html && !$this->attachments && null === parent::getBody()) {
+            throw new LogicException('A message must have a text or an HTML part or attachments.');
+        }
+    }
+
+    /**
+     * Generates an AbstractPart based on the raw body of a message.
+     *
+     * The most "complex" part generated by this method is when there is text and HTML bodies
+     * with related images for the HTML part and some attachments:
+     *
+     * multipart/mixed
+     *         |
+     *         |------------> multipart/related
+     *         |                      |
+     *         |                      |------------> multipart/alternative
+     *         |                      |                      |
+     *         |                      |                       ------------> text/plain (with content)
+     *         |                      |                      |
+     *         |                      |                       ------------> text/html (with content)
+     *         |                      |
+     *         |                       ------------> image/png (with content)
+     *         |
+     *          ------------> application/pdf (with content)
+     */
+    private function generateBody(): AbstractPart
+    {
+        if (null !== $this->cachedBody) {
+            return $this->cachedBody;
+        }
+
+        $this->ensureBodyValid();
+
+        [$htmlPart, $otherParts, $relatedParts] = $this->prepareParts();
+
+        $part = null === $this->text ? null : new TextPart($this->text, $this->textCharset);
+        if (null !== $htmlPart) {
+            if (null !== $part) {
+                $part = new AlternativePart($part, $htmlPart);
+            } else {
+                $part = $htmlPart;
+            }
+        }
+
+        if ($relatedParts) {
+            $part = new RelatedPart($part, ...$relatedParts);
+        }
+
+        if ($otherParts) {
+            if ($part) {
+                $part = new MixedPart($part, ...$otherParts);
+            } else {
+                $part = new MixedPart(...$otherParts);
+            }
+        }
+
+        return $this->cachedBody = $part;
+    }
+
+    private function prepareParts(): ?array
+    {
+        $names = [];
+        $htmlPart = null;
+        $html = $this->html;
+        if (null !== $html) {
+            $htmlPart = new TextPart($html, $this->htmlCharset, 'html');
+            $html = $htmlPart->getBody();
+
+            $regexes = [
+                '<img\s+[^>]*src\s*=\s*(?:([\'"])cid:(.+?)\\1|cid:([^>\s]+))',
+                '<\w+\s+[^>]*background\s*=\s*(?:([\'"])cid:(.+?)\\1|cid:([^>\s]+))',
+            ];
+            $tmpMatches = [];
+            foreach ($regexes as $regex) {
+                preg_match_all('/'.$regex.'/i', $html, $tmpMatches);
+                $names = array_merge($names, $tmpMatches[2], $tmpMatches[3]);
+            }
+            $names = array_filter(array_unique($names));
+        }
+
+        $otherParts = $relatedParts = [];
+        foreach ($this->attachments as $part) {
+            foreach ($names as $name) {
+                if ($name !== $part->getName() && (!$part->hasContentId() || $name !== $part->getContentId())) {
+                    continue;
+                }
+                if (isset($relatedParts[$name])) {
+                    continue 2;
+                }
+
+                if ($name !== $part->getContentId()) {
+                    $html = str_replace('cid:'.$name, 'cid:'.$part->getContentId(), $html, $count);
+                }
+                $relatedParts[$name] = $part;
+                $part->setName($part->getContentId())->asInline();
+
+                continue 2;
+            }
+
+            $otherParts[] = $part;
+        }
+        if (null !== $htmlPart) {
+            $htmlPart = new TextPart($html, $this->htmlCharset, 'html');
+        }
+
+        return [$htmlPart, $otherParts, array_values($relatedParts)];
+    }
+
+    /**
+     * @return $this
+     */
+    private function setHeaderBody(string $type, string $name, $body): static
+    {
+        $this->getHeaders()->setHeaderBody($type, $name, $body);
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    private function addListAddressHeaderBody(string $name, array $addresses): static
+    {
+        if (!$header = $this->getHeaders()->get($name)) {
+            return $this->setListAddressHeaderBody($name, $addresses);
+        }
+        $header->addAddresses(Address::createArray($addresses));
+
+        return $this;
+    }
+
+    /**
+     * @return $this
+     */
+    private function setListAddressHeaderBody(string $name, array $addresses): static
+    {
+        $addresses = Address::createArray($addresses);
+        $headers = $this->getHeaders();
+        if ($header = $headers->get($name)) {
+            $header->setAddresses($addresses);
+        } else {
+            $headers->addMailboxListHeader($name, $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @internal
+     */
+    public function __serialize(): array
+    {
+        if (\is_resource($this->text)) {
+            $this->text = (new TextPart($this->text))->getBody();
+        }
+
+        if (\is_resource($this->html)) {
+            $this->html = (new TextPart($this->html))->getBody();
+        }
+
+        return [$this->text, $this->textCharset, $this->html, $this->htmlCharset, $this->attachments, parent::__serialize()];
+    }
+
+    /**
+     * @internal
+     */
+    public function __unserialize(array $data): void
+    {
+        [$this->text, $this->textCharset, $this->html, $this->htmlCharset, $this->attachments, $parentData] = $data;
+
+        parent::__unserialize($parentData);
+    }
+}

lib/symfony/mime/Encoder/AddressEncoderInterface.php

@@ -0,0 +1,28 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+use Symfony\Component\Mime\Exception\AddressEncoderException;
+
+/**
+ * @author Christian Schmidt
+ */
+interface AddressEncoderInterface
+{
+    /**
+     * Encodes an email address.
+     *
+     * @throws AddressEncoderException if the email cannot be represented in
+     *                                 the encoding implemented by this class
+     */
+    public function encodeString(string $address): string;
+}

lib/symfony/mime/Encoder/Base64ContentEncoder.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+use Symfony\Component\Mime\Exception\RuntimeException;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class Base64ContentEncoder extends Base64Encoder implements ContentEncoderInterface
+{
+    public function encodeByteStream($stream, int $maxLineLength = 0): iterable
+    {
+        if (!\is_resource($stream)) {
+            throw new \TypeError(\sprintf('Method "%s" takes a stream as a first argument.', __METHOD__));
+        }
+
+        $filter = stream_filter_append($stream, 'convert.base64-encode', \STREAM_FILTER_READ, [
+            'line-length' => 0 >= $maxLineLength || 76 < $maxLineLength ? 76 : $maxLineLength,
+            'line-break-chars' => "\r\n",
+        ]);
+        if (!\is_resource($filter)) {
+            throw new RuntimeException('Unable to set the base64 content encoder to the filter.');
+        }
+
+        while (!feof($stream)) {
+            yield fread($stream, 16372);
+        }
+        stream_filter_remove($filter);
+    }
+
+    public function getName(): string
+    {
+        return 'base64';
+    }
+}

lib/symfony/mime/Encoder/Base64Encoder.php

@@ -0,0 +1,41 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+class Base64Encoder implements EncoderInterface
+{
+    /**
+     * Takes an unencoded string and produces a Base64 encoded string from it.
+     *
+     * Base64 encoded strings have a maximum line length of 76 characters.
+     * If the first line needs to be shorter, indicate the difference with
+     * $firstLineOffset.
+     */
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        if (0 >= $maxLineLength || 76 < $maxLineLength) {
+            $maxLineLength = 76;
+        }
+
+        $encodedString = base64_encode($string);
+        $firstLine = '';
+        if (0 !== $firstLineOffset) {
+            $firstLine = substr($encodedString, 0, $maxLineLength - $firstLineOffset)."\r\n";
+            $encodedString = substr($encodedString, $maxLineLength - $firstLineOffset);
+        }
+
+        return $firstLine.trim(chunk_split($encodedString, $maxLineLength, "\r\n"));
+    }
+}

lib/symfony/mime/Encoder/Base64MimeHeaderEncoder.php

@@ -0,0 +1,43 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+final class Base64MimeHeaderEncoder extends Base64Encoder implements MimeHeaderEncoderInterface
+{
+    public function getName(): string
+    {
+        return 'B';
+    }
+
+    /**
+     * Takes an unencoded string and produces a Base64 encoded string from it.
+     *
+     * If the charset is iso-2022-jp, it uses mb_encode_mimeheader instead of
+     * default encodeString, otherwise pass to the parent method.
+     */
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        if ('iso-2022-jp' === strtolower($charset)) {
+            $old = mb_internal_encoding();
+            mb_internal_encoding('utf-8');
+            $newstring = mb_encode_mimeheader($string, 'iso-2022-jp', $this->getName(), "\r\n");
+            mb_internal_encoding($old);
+
+            return $newstring;
+        }
+
+        return parent::encodeString($string, $charset, $firstLineOffset, $maxLineLength);
+    }
+}

lib/symfony/mime/Encoder/ContentEncoderInterface.php

@@ -0,0 +1,30 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+interface ContentEncoderInterface extends EncoderInterface
+{
+    /**
+     * Encodes the stream to a Generator.
+     *
+     * @param resource $stream
+     */
+    public function encodeByteStream($stream, int $maxLineLength = 0): iterable;
+
+    /**
+     * Gets the MIME name of this content encoding scheme.
+     */
+    public function getName(): string;
+}

lib/symfony/mime/Encoder/EightBitContentEncoder.php

@@ -0,0 +1,35 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class EightBitContentEncoder implements ContentEncoderInterface
+{
+    public function encodeByteStream($stream, int $maxLineLength = 0): iterable
+    {
+        while (!feof($stream)) {
+            yield fread($stream, 16372);
+        }
+    }
+
+    public function getName(): string
+    {
+        return '8bit';
+    }
+
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        return $string;
+    }
+}

lib/symfony/mime/Encoder/EncoderInterface.php

@@ -0,0 +1,26 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+interface EncoderInterface
+{
+    /**
+     * Encode a given string to produce an encoded string.
+     *
+     * @param int $firstLineOffset if first line needs to be shorter
+     * @param int $maxLineLength   - 0 indicates the default length for this encoding
+     */
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string;
+}

lib/symfony/mime/Encoder/IdnAddressEncoder.php

@@ -0,0 +1,44 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * An IDN email address encoder.
+ *
+ * Encodes the domain part of an address using IDN. This is compatible will all
+ * SMTP servers.
+ *
+ * Note: It leaves the local part as is. In case there are non-ASCII characters
+ * in the local part then it depends on the SMTP Server if this is supported.
+ *
+ * @author Christian Schmidt
+ */
+final class IdnAddressEncoder implements AddressEncoderInterface
+{
+    /**
+     * Encodes the domain part of an address using IDN.
+     */
+    public function encodeString(string $address): string
+    {
+        $i = strrpos($address, '@');
+        if (false !== $i) {
+            $local = substr($address, 0, $i);
+            $domain = substr($address, $i + 1);
+
+            if (preg_match('/[^\x00-\x7F]/', $domain)) {
+                $address = \sprintf('%s@%s', $local, idn_to_ascii($domain, \IDNA_DEFAULT | \IDNA_USE_STD3_RULES | \IDNA_CHECK_BIDI | \IDNA_CHECK_CONTEXTJ | \IDNA_NONTRANSITIONAL_TO_ASCII, \INTL_IDNA_VARIANT_UTS46));
+            }
+        }
+
+        return $address;
+    }
+}

lib/symfony/mime/Encoder/MimeHeaderEncoderInterface.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+interface MimeHeaderEncoderInterface
+{
+    /**
+     * Get the MIME name of this content encoding scheme.
+     */
+    public function getName(): string;
+}

lib/symfony/mime/Encoder/QpContentEncoder.php

@@ -0,0 +1,55 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Lars Strojny
+ */
+final class QpContentEncoder implements ContentEncoderInterface
+{
+    public function encodeByteStream($stream, int $maxLineLength = 0): iterable
+    {
+        if (!\is_resource($stream)) {
+            throw new \TypeError(\sprintf('Method "%s" takes a stream as a first argument.', __METHOD__));
+        }
+
+        // we don't use PHP stream filters here as the content should be small enough
+        yield $this->encodeString(stream_get_contents($stream), 'utf-8', 0, $maxLineLength);
+    }
+
+    public function getName(): string
+    {
+        return 'quoted-printable';
+    }
+
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        return $this->standardize(quoted_printable_encode($string));
+    }
+
+    /**
+     * Make sure CRLF is correct and HT/SPACE are in valid places.
+     */
+    private function standardize(string $string): string
+    {
+        // transform CR or LF to CRLF
+        $string = preg_replace('~=0D(?!=0A)|(?<!=0D)=0A~', '=0D=0A', $string);
+        // transform =0D=0A to CRLF
+        $string = str_replace(["\t=0D=0A", ' =0D=0A', '=0D=0A'], ["=09\r\n", "=20\r\n", "\r\n"], $string);
+
+        return match (\ord(substr($string, -1))) {
+            0x09 => substr_replace($string, '=09', -1),
+            0x20 => substr_replace($string, '=20', -1),
+            default => $string,
+        };
+    }
+}

lib/symfony/mime/Encoder/QpEncoder.php

@@ -0,0 +1,192 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+use Symfony\Component\Mime\CharacterStream;
+
+/**
+ * @author Chris Corbyn
+ */
+class QpEncoder implements EncoderInterface
+{
+    /**
+     * Pre-computed QP for HUGE optimization.
+     */
+    private const QP_MAP = [
+        0 => '=00', 1 => '=01', 2 => '=02', 3 => '=03', 4 => '=04',
+        5 => '=05', 6 => '=06', 7 => '=07', 8 => '=08', 9 => '=09',
+        10 => '=0A', 11 => '=0B', 12 => '=0C', 13 => '=0D', 14 => '=0E',
+        15 => '=0F', 16 => '=10', 17 => '=11', 18 => '=12', 19 => '=13',
+        20 => '=14', 21 => '=15', 22 => '=16', 23 => '=17', 24 => '=18',
+        25 => '=19', 26 => '=1A', 27 => '=1B', 28 => '=1C', 29 => '=1D',
+        30 => '=1E', 31 => '=1F', 32 => '=20', 33 => '=21', 34 => '=22',
+        35 => '=23', 36 => '=24', 37 => '=25', 38 => '=26', 39 => '=27',
+        40 => '=28', 41 => '=29', 42 => '=2A', 43 => '=2B', 44 => '=2C',
+        45 => '=2D', 46 => '=2E', 47 => '=2F', 48 => '=30', 49 => '=31',
+        50 => '=32', 51 => '=33', 52 => '=34', 53 => '=35', 54 => '=36',
+        55 => '=37', 56 => '=38', 57 => '=39', 58 => '=3A', 59 => '=3B',
+        60 => '=3C', 61 => '=3D', 62 => '=3E', 63 => '=3F', 64 => '=40',
+        65 => '=41', 66 => '=42', 67 => '=43', 68 => '=44', 69 => '=45',
+        70 => '=46', 71 => '=47', 72 => '=48', 73 => '=49', 74 => '=4A',
+        75 => '=4B', 76 => '=4C', 77 => '=4D', 78 => '=4E', 79 => '=4F',
+        80 => '=50', 81 => '=51', 82 => '=52', 83 => '=53', 84 => '=54',
+        85 => '=55', 86 => '=56', 87 => '=57', 88 => '=58', 89 => '=59',
+        90 => '=5A', 91 => '=5B', 92 => '=5C', 93 => '=5D', 94 => '=5E',
+        95 => '=5F', 96 => '=60', 97 => '=61', 98 => '=62', 99 => '=63',
+        100 => '=64', 101 => '=65', 102 => '=66', 103 => '=67', 104 => '=68',
+        105 => '=69', 106 => '=6A', 107 => '=6B', 108 => '=6C', 109 => '=6D',
+        110 => '=6E', 111 => '=6F', 112 => '=70', 113 => '=71', 114 => '=72',
+        115 => '=73', 116 => '=74', 117 => '=75', 118 => '=76', 119 => '=77',
+        120 => '=78', 121 => '=79', 122 => '=7A', 123 => '=7B', 124 => '=7C',
+        125 => '=7D', 126 => '=7E', 127 => '=7F', 128 => '=80', 129 => '=81',
+        130 => '=82', 131 => '=83', 132 => '=84', 133 => '=85', 134 => '=86',
+        135 => '=87', 136 => '=88', 137 => '=89', 138 => '=8A', 139 => '=8B',
+        140 => '=8C', 141 => '=8D', 142 => '=8E', 143 => '=8F', 144 => '=90',
+        145 => '=91', 146 => '=92', 147 => '=93', 148 => '=94', 149 => '=95',
+        150 => '=96', 151 => '=97', 152 => '=98', 153 => '=99', 154 => '=9A',
+        155 => '=9B', 156 => '=9C', 157 => '=9D', 158 => '=9E', 159 => '=9F',
+        160 => '=A0', 161 => '=A1', 162 => '=A2', 163 => '=A3', 164 => '=A4',
+        165 => '=A5', 166 => '=A6', 167 => '=A7', 168 => '=A8', 169 => '=A9',
+        170 => '=AA', 171 => '=AB', 172 => '=AC', 173 => '=AD', 174 => '=AE',
+        175 => '=AF', 176 => '=B0', 177 => '=B1', 178 => '=B2', 179 => '=B3',
+        180 => '=B4', 181 => '=B5', 182 => '=B6', 183 => '=B7', 184 => '=B8',
+        185 => '=B9', 186 => '=BA', 187 => '=BB', 188 => '=BC', 189 => '=BD',
+        190 => '=BE', 191 => '=BF', 192 => '=C0', 193 => '=C1', 194 => '=C2',
+        195 => '=C3', 196 => '=C4', 197 => '=C5', 198 => '=C6', 199 => '=C7',
+        200 => '=C8', 201 => '=C9', 202 => '=CA', 203 => '=CB', 204 => '=CC',
+        205 => '=CD', 206 => '=CE', 207 => '=CF', 208 => '=D0', 209 => '=D1',
+        210 => '=D2', 211 => '=D3', 212 => '=D4', 213 => '=D5', 214 => '=D6',
+        215 => '=D7', 216 => '=D8', 217 => '=D9', 218 => '=DA', 219 => '=DB',
+        220 => '=DC', 221 => '=DD', 222 => '=DE', 223 => '=DF', 224 => '=E0',
+        225 => '=E1', 226 => '=E2', 227 => '=E3', 228 => '=E4', 229 => '=E5',
+        230 => '=E6', 231 => '=E7', 232 => '=E8', 233 => '=E9', 234 => '=EA',
+        235 => '=EB', 236 => '=EC', 237 => '=ED', 238 => '=EE', 239 => '=EF',
+        240 => '=F0', 241 => '=F1', 242 => '=F2', 243 => '=F3', 244 => '=F4',
+        245 => '=F5', 246 => '=F6', 247 => '=F7', 248 => '=F8', 249 => '=F9',
+        250 => '=FA', 251 => '=FB', 252 => '=FC', 253 => '=FD', 254 => '=FE',
+        255 => '=FF',
+    ];
+
+    private static array $safeMapShare = [];
+
+    /**
+     * A map of non-encoded ascii characters.
+     *
+     * @var string[]
+     *
+     * @internal
+     */
+    protected array $safeMap = [];
+
+    public function __construct()
+    {
+        $id = static::class;
+        if (!isset(self::$safeMapShare[$id])) {
+            $this->initSafeMap();
+            self::$safeMapShare[$id] = $this->safeMap;
+        } else {
+            $this->safeMap = self::$safeMapShare[$id];
+        }
+    }
+
+    protected function initSafeMap(): void
+    {
+        foreach (array_merge([0x09, 0x20], range(0x21, 0x3C), range(0x3E, 0x7E)) as $byte) {
+            $this->safeMap[$byte] = \chr($byte);
+        }
+    }
+
+    /**
+     * Takes an unencoded string and produces a QP encoded string from it.
+     *
+     * QP encoded strings have a maximum line length of 76 characters.
+     * If the first line needs to be shorter, indicate the difference with
+     * $firstLineOffset.
+     */
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        if ($maxLineLength > 76 || $maxLineLength <= 0) {
+            $maxLineLength = 76;
+        }
+
+        $thisLineLength = $maxLineLength - $firstLineOffset;
+
+        $lines = [];
+        $lNo = 0;
+        $lines[$lNo] = '';
+        $currentLine = &$lines[$lNo++];
+        $size = $lineLen = 0;
+        $charStream = new CharacterStream($string, $charset);
+
+        // Fetching more than 4 chars at one is slower, as is fetching fewer bytes
+        // Conveniently 4 chars is the UTF-8 safe number since UTF-8 has up to 6
+        // bytes per char and (6 * 4 * 3 = 72 chars per line) * =NN is 3 bytes
+        while (null !== $bytes = $charStream->readBytes(4)) {
+            $enc = $this->encodeByteSequence($bytes, $size);
+
+            $i = strpos($enc, '=0D=0A');
+            $newLineLength = $lineLen + (false === $i ? $size : $i);
+
+            if ($currentLine && $newLineLength >= $thisLineLength) {
+                $lines[$lNo] = '';
+                $currentLine = &$lines[$lNo++];
+                $thisLineLength = $maxLineLength;
+                $lineLen = 0;
+            }
+
+            $currentLine .= $enc;
+
+            if (false === $i) {
+                $lineLen += $size;
+            } else {
+                // 6 is the length of '=0D=0A'.
+                $lineLen = $size - strrpos($enc, '=0D=0A') - 6;
+            }
+        }
+
+        return $this->standardize(implode("=\r\n", $lines));
+    }
+
+    /**
+     * Encode the given byte array into a verbatim QP form.
+     */
+    private function encodeByteSequence(array $bytes, int &$size): string
+    {
+        $ret = '';
+        $size = 0;
+        foreach ($bytes as $b) {
+            if (isset($this->safeMap[$b])) {
+                $ret .= $this->safeMap[$b];
+                ++$size;
+            } else {
+                $ret .= self::QP_MAP[$b];
+                $size += 3;
+            }
+        }
+
+        return $ret;
+    }
+
+    /**
+     * Make sure CRLF is correct and HT/SPACE are in valid places.
+     */
+    private function standardize(string $string): string
+    {
+        $string = str_replace(["\t=0D=0A", ' =0D=0A', '=0D=0A'], ["=09\r\n", "=20\r\n", "\r\n"], $string);
+
+        return match ($end = \ord(substr($string, -1))) {
+            0x09,
+            0x20 => substr_replace($string, self::QP_MAP[$end], -1),
+            default => $string,
+        };
+    }
+}

lib/symfony/mime/Encoder/QpMimeHeaderEncoder.php

@@ -0,0 +1,40 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+final class QpMimeHeaderEncoder extends QpEncoder implements MimeHeaderEncoderInterface
+{
+    protected function initSafeMap(): void
+    {
+        foreach (array_merge(
+            range(0x61, 0x7A), range(0x41, 0x5A),
+            range(0x30, 0x39), [0x20, 0x21, 0x2A, 0x2B, 0x2D, 0x2F]
+        ) as $byte) {
+            $this->safeMap[$byte] = \chr($byte);
+        }
+    }
+
+    public function getName(): string
+    {
+        return 'Q';
+    }
+
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        return str_replace([' ', '=20', "=\r\n"], ['_', '_', "\r\n"],
+            parent::encodeString($string, $charset, $firstLineOffset, $maxLineLength)
+        );
+    }
+}

lib/symfony/mime/Encoder/Rfc2231Encoder.php

@@ -0,0 +1,50 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Encoder;
+
+use Symfony\Component\Mime\CharacterStream;
+
+/**
+ * @author Chris Corbyn
+ */
+final class Rfc2231Encoder implements EncoderInterface
+{
+    /**
+     * Takes an unencoded string and produces a string encoded according to RFC 2231 from it.
+     */
+    public function encodeString(string $string, ?string $charset = 'utf-8', int $firstLineOffset = 0, int $maxLineLength = 0): string
+    {
+        $lines = [];
+        $lineCount = 0;
+        $lines[] = '';
+        $currentLine = &$lines[$lineCount++];
+
+        if (0 >= $maxLineLength) {
+            $maxLineLength = 75;
+        }
+
+        $charStream = new CharacterStream($string, $charset);
+        $thisLineLength = $maxLineLength - $firstLineOffset;
+
+        while (null !== $char = $charStream->read(4)) {
+            $encodedChar = rawurlencode($char);
+            if ('' !== $currentLine && \strlen($currentLine.$encodedChar) > $thisLineLength) {
+                $lines[] = '';
+                $currentLine = &$lines[$lineCount++];
+                $thisLineLength = $maxLineLength;
+            }
+            $currentLine .= $encodedChar;
+        }
+
+        return implode("\r\n", $lines);
+    }
+}

lib/symfony/mime/Exception/AddressEncoderException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class AddressEncoderException extends RfcComplianceException
+{
+}

lib/symfony/mime/Exception/ExceptionInterface.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface ExceptionInterface extends \Throwable
+{
+}

lib/symfony/mime/Exception/InvalidArgumentException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class InvalidArgumentException extends \InvalidArgumentException implements ExceptionInterface
+{
+}

lib/symfony/mime/Exception/LogicException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class LogicException extends \LogicException implements ExceptionInterface
+{
+}

lib/symfony/mime/Exception/RfcComplianceException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class RfcComplianceException extends \InvalidArgumentException implements ExceptionInterface
+{
+}

lib/symfony/mime/Exception/RuntimeException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class RuntimeException extends \RuntimeException implements ExceptionInterface
+{
+}

lib/symfony/mime/FileBinaryMimeTypeGuesser.php

@@ -0,0 +1,87 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Exception\LogicException;
+
+/**
+ * Guesses the MIME type with the binary "file" (only available on *nix).
+ *
+ * @author Bernhard Schussek <bschussek@gmail.com>
+ */
+class FileBinaryMimeTypeGuesser implements MimeTypeGuesserInterface
+{
+    private string $cmd;
+
+    /**
+     * The $cmd pattern must contain a "%s" string that will be replaced
+     * with the file name to guess.
+     *
+     * The command output must start with the MIME type of the file.
+     *
+     * @param string $cmd The command to run to get the MIME type of a file
+     */
+    public function __construct(string $cmd = 'file -b --mime -- %s 2>/dev/null')
+    {
+        $this->cmd = $cmd;
+    }
+
+    public function isGuesserSupported(): bool
+    {
+        static $supported = null;
+
+        if (null !== $supported) {
+            return $supported;
+        }
+
+        if ('\\' === \DIRECTORY_SEPARATOR || !\function_exists('passthru') || !\function_exists('escapeshellarg')) {
+            return $supported = false;
+        }
+
+        ob_start();
+        passthru('command -v file', $exitStatus);
+        $binPath = trim(ob_get_clean());
+
+        return $supported = 0 === $exitStatus && '' !== $binPath;
+    }
+
+    public function guessMimeType(string $path): ?string
+    {
+        if (!is_file($path) || !is_readable($path)) {
+            throw new InvalidArgumentException(\sprintf('The "%s" file does not exist or is not readable.', $path));
+        }
+
+        if (!$this->isGuesserSupported()) {
+            throw new LogicException(\sprintf('The "%s" guesser is not supported.', __CLASS__));
+        }
+
+        ob_start();
+
+        // need to use --mime instead of -i. see #6641
+        passthru(\sprintf($this->cmd, escapeshellarg((str_starts_with($path, '-') ? './' : '').$path)), $return);
+        if ($return > 0) {
+            ob_end_clean();
+
+            return null;
+        }
+
+        $type = trim(ob_get_clean());
+
+        if (!preg_match('#^([a-z0-9\-]+/[a-z0-9\-\+\.]+)#i', $type, $match)) {
+            // it's not a type, but an error message
+            return null;
+        }
+
+        return $match[1];
+    }
+}

lib/symfony/mime/FileinfoMimeTypeGuesser.php

@@ -0,0 +1,63 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Exception\LogicException;
+
+/**
+ * Guesses the MIME type using the PECL extension FileInfo.
+ *
+ * @author Bernhard Schussek <bschussek@gmail.com>
+ */
+class FileinfoMimeTypeGuesser implements MimeTypeGuesserInterface
+{
+    private ?string $magicFile;
+
+    /**
+     * @param string|null $magicFile A magic file to use with the finfo instance
+     *
+     * @see https://php.net/finfo-open
+     */
+    public function __construct(?string $magicFile = null)
+    {
+        $this->magicFile = $magicFile;
+    }
+
+    public function isGuesserSupported(): bool
+    {
+        return \function_exists('finfo_open');
+    }
+
+    public function guessMimeType(string $path): ?string
+    {
+        if (!is_file($path) || !is_readable($path)) {
+            throw new InvalidArgumentException(\sprintf('The "%s" file does not exist or is not readable.', $path));
+        }
+
+        if (!$this->isGuesserSupported()) {
+            throw new LogicException(\sprintf('The "%s" guesser is not supported.', __CLASS__));
+        }
+
+        if (false === $finfo = new \finfo(\FILEINFO_MIME_TYPE, $this->magicFile)) {
+            return null;
+        }
+        $mimeType = $finfo->file($path);
+
+        if ($mimeType && 0 === (\strlen($mimeType) % 2)) {
+            $mimeStart = substr($mimeType, 0, \strlen($mimeType) >> 1);
+            $mimeType = $mimeStart.$mimeStart === $mimeType ? $mimeStart : $mimeType;
+        }
+
+        return $mimeType;
+    }
+}

lib/symfony/mime/Header/AbstractHeader.php

@@ -0,0 +1,302 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Encoder\QpMimeHeaderEncoder;
+
+/**
+ * An abstract base MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+abstract class AbstractHeader implements HeaderInterface
+{
+    public const PHRASE_PATTERN = '(?:(?:(?:(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?[a-zA-Z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\}\|~]+(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?)|(?:(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?"((?:(?:[ \t]*(?:\r\n))?[ \t])?(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21\x23-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])))*(?:(?:[ \t]*(?:\r\n))?[ \t])?"(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?))+?)';
+
+    private static QpMimeHeaderEncoder $encoder;
+
+    private string $name;
+    private int $lineLength = 76;
+    private ?string $lang = null;
+    private string $charset = 'utf-8';
+
+    public function __construct(string $name)
+    {
+        $this->name = $name;
+    }
+
+    /**
+     * @return void
+     */
+    public function setCharset(string $charset)
+    {
+        $this->charset = $charset;
+    }
+
+    public function getCharset(): ?string
+    {
+        return $this->charset;
+    }
+
+    /**
+     * Set the language used in this Header.
+     *
+     * For example, for US English, 'en-us'.
+     *
+     * @return void
+     */
+    public function setLanguage(string $lang)
+    {
+        $this->lang = $lang;
+    }
+
+    public function getLanguage(): ?string
+    {
+        return $this->lang;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * @return void
+     */
+    public function setMaxLineLength(int $lineLength)
+    {
+        $this->lineLength = $lineLength;
+    }
+
+    public function getMaxLineLength(): int
+    {
+        return $this->lineLength;
+    }
+
+    public function toString(): string
+    {
+        return $this->tokensToString($this->toTokens());
+    }
+
+    /**
+     * Produces a compliant, formatted RFC 2822 'phrase' based on the string given.
+     *
+     * @param string $string  as displayed
+     * @param bool   $shorten the first line to make remove for header name
+     */
+    protected function createPhrase(HeaderInterface $header, string $string, string $charset, bool $shorten = false): string
+    {
+        // Treat token as exactly what was given
+        $phraseStr = $string;
+
+        // If it's not valid
+        if (!preg_match('/^'.self::PHRASE_PATTERN.'$/D', $phraseStr)) {
+            // .. but it is just ascii text, try escaping some characters
+            // and make it a quoted-string
+            if (preg_match('/^[\x00-\x08\x0B\x0C\x0E-\x7F]*$/D', $phraseStr)) {
+                foreach (['\\', '"'] as $char) {
+                    $phraseStr = str_replace($char, '\\'.$char, $phraseStr);
+                }
+                $phraseStr = '"'.$phraseStr.'"';
+            } else {
+                // ... otherwise it needs encoding
+                // Determine space remaining on line if first line
+                if ($shorten) {
+                    $usedLength = \strlen($header->getName().': ');
+                } else {
+                    $usedLength = 0;
+                }
+                $phraseStr = $this->encodeWords($header, $string, $usedLength);
+            }
+        } elseif (str_contains($phraseStr, '(')) {
+            foreach (['\\', '"'] as $char) {
+                $phraseStr = str_replace($char, '\\'.$char, $phraseStr);
+            }
+            $phraseStr = '"'.$phraseStr.'"';
+        }
+
+        return $phraseStr;
+    }
+
+    /**
+     * Encode needed word tokens within a string of input.
+     */
+    protected function encodeWords(HeaderInterface $header, string $input, int $usedLength = -1): string
+    {
+        $value = '';
+        $tokens = $this->getEncodableWordTokens($input);
+        foreach ($tokens as $token) {
+            // See RFC 2822, Sect 2.2 (really 2.2 ??)
+            if ($this->tokenNeedsEncoding($token)) {
+                // Don't encode starting WSP
+                $firstChar = substr($token, 0, 1);
+                switch ($firstChar) {
+                    case ' ':
+                    case "\t":
+                        $value .= $firstChar;
+                        $token = substr($token, 1);
+                }
+
+                if (-1 == $usedLength) {
+                    $usedLength = \strlen($header->getName().': ') + \strlen($value);
+                }
+                $value .= $this->getTokenAsEncodedWord($token, $usedLength);
+            } else {
+                $value .= $token;
+            }
+        }
+
+        return $value;
+    }
+
+    protected function tokenNeedsEncoding(string $token): bool
+    {
+        return (bool) preg_match('~[\x00-\x08\x10-\x19\x7F-\xFF\r\n]~', $token);
+    }
+
+    /**
+     * Splits a string into tokens in blocks of words which can be encoded quickly.
+     *
+     * @return string[]
+     */
+    protected function getEncodableWordTokens(string $string): array
+    {
+        $tokens = [];
+        $encodedToken = '';
+        // Split at all whitespace boundaries
+        foreach (preg_split('~(?=[\t ])~', $string) as $token) {
+            if ($this->tokenNeedsEncoding($token)) {
+                $encodedToken .= $token;
+            } else {
+                if ('' !== $encodedToken) {
+                    $tokens[] = $encodedToken;
+                    $encodedToken = '';
+                }
+                $tokens[] = $token;
+            }
+        }
+        if ('' !== $encodedToken) {
+            $tokens[] = $encodedToken;
+        }
+
+        foreach ($tokens as $i => $token) {
+            // whitespace(s) between 2 encoded tokens
+            if (
+                0 < $i
+                && isset($tokens[$i + 1])
+                && preg_match('~^[\t ]+$~', $token)
+                && $this->tokenNeedsEncoding($tokens[$i - 1])
+                && $this->tokenNeedsEncoding($tokens[$i + 1])
+            ) {
+                $tokens[$i - 1] .= $token.$tokens[$i + 1];
+                array_splice($tokens, $i, 2);
+            }
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Get a token as an encoded word for safe insertion into headers.
+     */
+    protected function getTokenAsEncodedWord(string $token, int $firstLineOffset = 0): string
+    {
+        self::$encoder ??= new QpMimeHeaderEncoder();
+
+        // Adjust $firstLineOffset to account for space needed for syntax
+        $charsetDecl = $this->charset;
+        if (null !== $this->lang) {
+            $charsetDecl .= '*'.$this->lang;
+        }
+        $encodingWrapperLength = \strlen('=?'.$charsetDecl.'?'.self::$encoder->getName().'??=');
+
+        if ($firstLineOffset >= 75) {
+            // Does this logic need to be here?
+            $firstLineOffset = 0;
+        }
+
+        $encodedTextLines = explode("\r\n",
+            self::$encoder->encodeString($token, $this->charset, $firstLineOffset, 75 - $encodingWrapperLength)
+        );
+
+        if ('iso-2022-jp' !== strtolower($this->charset)) {
+            // special encoding for iso-2022-jp using mb_encode_mimeheader
+            foreach ($encodedTextLines as $lineNum => $line) {
+                $encodedTextLines[$lineNum] = '=?'.$charsetDecl.'?'.self::$encoder->getName().'?'.$line.'?=';
+            }
+        }
+
+        return implode("\r\n ", $encodedTextLines);
+    }
+
+    /**
+     * Generates tokens from the given string which include CRLF as individual tokens.
+     *
+     * @return string[]
+     */
+    protected function generateTokenLines(string $token): array
+    {
+        return preg_split('~(\r\n)~', $token, -1, \PREG_SPLIT_DELIM_CAPTURE);
+    }
+
+    /**
+     * Generate a list of all tokens in the final header.
+     */
+    protected function toTokens(?string $string = null): array
+    {
+        $string ??= $this->getBodyAsString();
+
+        $tokens = [];
+        // Generate atoms; split at all invisible boundaries followed by WSP
+        foreach (preg_split('~(?=[ \t])~', $string) as $token) {
+            $newTokens = $this->generateTokenLines($token);
+            foreach ($newTokens as $newToken) {
+                $tokens[] = $newToken;
+            }
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Takes an array of tokens which appear in the header and turns them into
+     * an RFC 2822 compliant string, adding FWSP where needed.
+     *
+     * @param string[] $tokens
+     */
+    private function tokensToString(array $tokens): string
+    {
+        $lineCount = 0;
+        $headerLines = [];
+        $headerLines[] = $this->name.': ';
+        $currentLine = &$headerLines[$lineCount++];
+
+        // Build all tokens back into compliant header
+        foreach ($tokens as $i => $token) {
+            // Line longer than specified maximum or token was just a new line
+            if (("\r\n" === $token)
+                || ($i > 0 && \strlen($currentLine.$token) > $this->lineLength)
+                && '' !== $currentLine) {
+                $headerLines[] = '';
+                $currentLine = &$headerLines[$lineCount++];
+            }
+
+            // Append token to the line
+            if ("\r\n" !== $token) {
+                $currentLine .= $token;
+            }
+        }
+
+        // Implode with FWS (RFC 2822, 2.2.3)
+        return implode("\r\n", $headerLines);
+    }
+}

lib/symfony/mime/Header/DateHeader.php

@@ -0,0 +1,62 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+/**
+ * A Date MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+final class DateHeader extends AbstractHeader
+{
+    private \DateTimeImmutable $dateTime;
+
+    public function __construct(string $name, \DateTimeInterface $date)
+    {
+        parent::__construct($name);
+
+        $this->setDateTime($date);
+    }
+
+    /**
+     * @param \DateTimeInterface $body
+     */
+    public function setBody(mixed $body): void
+    {
+        $this->setDateTime($body);
+    }
+
+    public function getBody(): \DateTimeImmutable
+    {
+        return $this->getDateTime();
+    }
+
+    public function getDateTime(): \DateTimeImmutable
+    {
+        return $this->dateTime;
+    }
+
+    /**
+     * Set the date-time of the Date in this Header.
+     *
+     * If a DateTime instance is provided, it is converted to DateTimeImmutable.
+     */
+    public function setDateTime(\DateTimeInterface $dateTime): void
+    {
+        $this->dateTime = \DateTimeImmutable::createFromInterface($dateTime);
+    }
+
+    public function getBodyAsString(): string
+    {
+        return $this->dateTime->format(\DateTimeInterface::RFC2822);
+    }
+}

lib/symfony/mime/Header/HeaderInterface.php

@@ -0,0 +1,72 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+/**
+ * A MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+interface HeaderInterface
+{
+    /**
+     * Sets the body.
+     *
+     * The type depends on the Header concrete class.
+     *
+     * @return void
+     */
+    public function setBody(mixed $body);
+
+    /**
+     * Gets the body.
+     *
+     * The return type depends on the Header concrete class.
+     */
+    public function getBody(): mixed;
+
+    /**
+     * @return void
+     */
+    public function setCharset(string $charset);
+
+    public function getCharset(): ?string;
+
+    /**
+     * @return void
+     */
+    public function setLanguage(string $lang);
+
+    public function getLanguage(): ?string;
+
+    public function getName(): string;
+
+    /**
+     * @return void
+     */
+    public function setMaxLineLength(int $lineLength);
+
+    public function getMaxLineLength(): int;
+
+    /**
+     * Gets this Header rendered as a compliant string.
+     */
+    public function toString(): string;
+
+    /**
+     * Gets the header's body, prepared for folding into a final header value.
+     *
+     * This is not necessarily RFC 2822 compliant since folding white space is
+     * not added at this stage (see {@link toString()} for that).
+     */
+    public function getBodyAsString(): string;
+}

lib/symfony/mime/Header/Headers.php

@@ -0,0 +1,316 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Exception\LogicException;
+
+/**
+ * A collection of headers.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class Headers
+{
+    private const UNIQUE_HEADERS = [
+        'date', 'from', 'sender', 'reply-to', 'to', 'cc', 'bcc',
+        'message-id', 'in-reply-to', 'references', 'subject',
+    ];
+    private const HEADER_CLASS_MAP = [
+        'date' => DateHeader::class,
+        'from' => MailboxListHeader::class,
+        'sender' => MailboxHeader::class,
+        'reply-to' => MailboxListHeader::class,
+        'to' => MailboxListHeader::class,
+        'cc' => MailboxListHeader::class,
+        'bcc' => MailboxListHeader::class,
+        'message-id' => IdentificationHeader::class,
+        'in-reply-to' => [UnstructuredHeader::class, IdentificationHeader::class], // `In-Reply-To` and `References` are less strict than RFC 2822 (3.6.4) to allow users entering the original email's ...
+        'references' => [UnstructuredHeader::class, IdentificationHeader::class], // ... `Message-ID`, even if that is no valid `msg-id`
+        'return-path' => PathHeader::class,
+    ];
+
+    /**
+     * @var HeaderInterface[][]
+     */
+    private array $headers = [];
+    private int $lineLength = 76;
+
+    public function __construct(HeaderInterface ...$headers)
+    {
+        foreach ($headers as $header) {
+            $this->add($header);
+        }
+    }
+
+    public function __clone()
+    {
+        foreach ($this->headers as $name => $collection) {
+            foreach ($collection as $i => $header) {
+                $this->headers[$name][$i] = clone $header;
+            }
+        }
+    }
+
+    public function setMaxLineLength(int $lineLength): void
+    {
+        $this->lineLength = $lineLength;
+        foreach ($this->all() as $header) {
+            $header->setMaxLineLength($lineLength);
+        }
+    }
+
+    public function getMaxLineLength(): int
+    {
+        return $this->lineLength;
+    }
+
+    /**
+     * @param array<Address|string> $addresses
+     *
+     * @return $this
+     */
+    public function addMailboxListHeader(string $name, array $addresses): static
+    {
+        return $this->add(new MailboxListHeader($name, Address::createArray($addresses)));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addMailboxHeader(string $name, Address|string $address): static
+    {
+        return $this->add(new MailboxHeader($name, Address::create($address)));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addIdHeader(string $name, string|array $ids): static
+    {
+        return $this->add(new IdentificationHeader($name, $ids));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addPathHeader(string $name, Address|string $path): static
+    {
+        return $this->add(new PathHeader($name, $path instanceof Address ? $path : new Address($path)));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addDateHeader(string $name, \DateTimeInterface $dateTime): static
+    {
+        return $this->add(new DateHeader($name, $dateTime));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addTextHeader(string $name, string $value): static
+    {
+        return $this->add(new UnstructuredHeader($name, $value));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addParameterizedHeader(string $name, string $value, array $params = []): static
+    {
+        return $this->add(new ParameterizedHeader($name, $value, $params));
+    }
+
+    /**
+     * @return $this
+     */
+    public function addHeader(string $name, mixed $argument, array $more = []): static
+    {
+        $headerClass = self::HEADER_CLASS_MAP[strtolower($name)] ?? UnstructuredHeader::class;
+        if (\is_array($headerClass)) {
+            $headerClass = $headerClass[0];
+        }
+        $parts = explode('\\', $headerClass);
+        $method = 'add'.ucfirst(array_pop($parts));
+        if ('addUnstructuredHeader' === $method) {
+            $method = 'addTextHeader';
+        } elseif ('addIdentificationHeader' === $method) {
+            $method = 'addIdHeader';
+        } elseif ('addMailboxListHeader' === $method && !\is_array($argument)) {
+            $argument = [$argument];
+        }
+
+        return $this->$method($name, $argument, $more);
+    }
+
+    public function has(string $name): bool
+    {
+        return isset($this->headers[strtolower($name)]);
+    }
+
+    /**
+     * @return $this
+     */
+    public function add(HeaderInterface $header): static
+    {
+        self::checkHeaderClass($header);
+
+        $header->setMaxLineLength($this->lineLength);
+        $name = strtolower($header->getName());
+
+        if (\in_array($name, self::UNIQUE_HEADERS, true) && isset($this->headers[$name]) && \count($this->headers[$name]) > 0) {
+            throw new LogicException(\sprintf('Impossible to set header "%s" as it\'s already defined and must be unique.', $header->getName()));
+        }
+
+        $this->headers[$name][] = $header;
+
+        return $this;
+    }
+
+    public function get(string $name): ?HeaderInterface
+    {
+        $name = strtolower($name);
+        if (!isset($this->headers[$name])) {
+            return null;
+        }
+
+        $values = array_values($this->headers[$name]);
+
+        return array_shift($values);
+    }
+
+    public function all(?string $name = null): iterable
+    {
+        if (null === $name) {
+            foreach ($this->headers as $name => $collection) {
+                foreach ($collection as $header) {
+                    yield $name => $header;
+                }
+            }
+        } elseif (isset($this->headers[strtolower($name)])) {
+            foreach ($this->headers[strtolower($name)] as $header) {
+                yield $header;
+            }
+        }
+    }
+
+    public function getNames(): array
+    {
+        return array_keys($this->headers);
+    }
+
+    public function remove(string $name): void
+    {
+        unset($this->headers[strtolower($name)]);
+    }
+
+    public static function isUniqueHeader(string $name): bool
+    {
+        return \in_array(strtolower($name), self::UNIQUE_HEADERS, true);
+    }
+
+    /**
+     * @throws LogicException if the header name and class are not compatible
+     */
+    public static function checkHeaderClass(HeaderInterface $header): void
+    {
+        $name = strtolower($header->getName());
+        $headerClasses = self::HEADER_CLASS_MAP[$name] ?? [];
+        if (!\is_array($headerClasses)) {
+            $headerClasses = [$headerClasses];
+        }
+
+        if (!$headerClasses) {
+            return;
+        }
+
+        foreach ($headerClasses as $c) {
+            if ($header instanceof $c) {
+                return;
+            }
+        }
+
+        throw new LogicException(\sprintf('The "%s" header must be an instance of "%s" (got "%s").', $header->getName(), implode('" or "', $headerClasses), get_debug_type($header)));
+    }
+
+    public function toString(): string
+    {
+        $string = '';
+        foreach ($this->toArray() as $str) {
+            $string .= $str."\r\n";
+        }
+
+        return $string;
+    }
+
+    public function toArray(): array
+    {
+        $arr = [];
+        foreach ($this->all() as $header) {
+            if ('' !== $header->getBodyAsString()) {
+                $arr[] = $header->toString();
+            }
+        }
+
+        return $arr;
+    }
+
+    public function getHeaderBody(string $name): mixed
+    {
+        return $this->has($name) ? $this->get($name)->getBody() : null;
+    }
+
+    /**
+     * @internal
+     */
+    public function setHeaderBody(string $type, string $name, mixed $body): void
+    {
+        if ($this->has($name)) {
+            $this->get($name)->setBody($body);
+        } else {
+            $this->{'add'.$type.'Header'}($name, $body);
+        }
+    }
+
+    public function getHeaderParameter(string $name, string $parameter): ?string
+    {
+        if (!$this->has($name)) {
+            return null;
+        }
+
+        $header = $this->get($name);
+        if (!$header instanceof ParameterizedHeader) {
+            throw new LogicException(\sprintf('Unable to get parameter "%s" on header "%s" as the header is not of class "%s".', $parameter, $name, ParameterizedHeader::class));
+        }
+
+        return $header->getParameter($parameter);
+    }
+
+    /**
+     * @internal
+     */
+    public function setHeaderParameter(string $name, string $parameter, ?string $value): void
+    {
+        if (!$this->has($name)) {
+            throw new LogicException(\sprintf('Unable to set parameter "%s" on header "%s" as the header is not defined.', $parameter, $name));
+        }
+
+        $header = $this->get($name);
+        if (!$header instanceof ParameterizedHeader) {
+            throw new LogicException(\sprintf('Unable to set parameter "%s" on header "%s" as the header is not of class "%s".', $parameter, $name, ParameterizedHeader::class));
+        }
+
+        $header->setParameter($parameter, $value);
+    }
+}

lib/symfony/mime/Header/IdentificationHeader.php

@@ -0,0 +1,107 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Exception\RfcComplianceException;
+
+/**
+ * An ID MIME Header for something like Message-ID or Content-ID (one or more addresses).
+ *
+ * @author Chris Corbyn
+ */
+final class IdentificationHeader extends AbstractHeader
+{
+    private array $ids = [];
+    private array $idsAsAddresses = [];
+
+    public function __construct(string $name, string|array $ids)
+    {
+        parent::__construct($name);
+
+        $this->setId($ids);
+    }
+
+    /**
+     * @param string|string[] $body a string ID or an array of IDs
+     *
+     * @throws RfcComplianceException
+     */
+    public function setBody(mixed $body): void
+    {
+        $this->setId($body);
+    }
+
+    public function getBody(): array
+    {
+        return $this->getIds();
+    }
+
+    /**
+     * Set the ID used in the value of this header.
+     *
+     * @param string|string[] $id
+     *
+     * @throws RfcComplianceException
+     */
+    public function setId(string|array $id): void
+    {
+        $this->setIds(\is_array($id) ? $id : [$id]);
+    }
+
+    /**
+     * Get the ID used in the value of this Header.
+     *
+     * If multiple IDs are set only the first is returned.
+     */
+    public function getId(): ?string
+    {
+        return $this->ids[0] ?? null;
+    }
+
+    /**
+     * Set a collection of IDs to use in the value of this Header.
+     *
+     * @param string[] $ids
+     *
+     * @throws RfcComplianceException
+     */
+    public function setIds(array $ids): void
+    {
+        $this->ids = [];
+        $this->idsAsAddresses = [];
+        foreach ($ids as $id) {
+            $this->idsAsAddresses[] = new Address($id);
+            $this->ids[] = $id;
+        }
+    }
+
+    /**
+     * Get the list of IDs used in this Header.
+     *
+     * @return string[]
+     */
+    public function getIds(): array
+    {
+        return $this->ids;
+    }
+
+    public function getBodyAsString(): string
+    {
+        $addrs = [];
+        foreach ($this->idsAsAddresses as $address) {
+            $addrs[] = '<'.$address->toString().'>';
+        }
+
+        return implode(' ', $addrs);
+    }
+}

lib/symfony/mime/Header/MailboxHeader.php

@@ -0,0 +1,85 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Exception\RfcComplianceException;
+
+/**
+ * A Mailbox MIME Header for something like Sender (one named address).
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class MailboxHeader extends AbstractHeader
+{
+    private Address $address;
+
+    public function __construct(string $name, Address $address)
+    {
+        parent::__construct($name);
+
+        $this->setAddress($address);
+    }
+
+    /**
+     * @param Address $body
+     *
+     * @throws RfcComplianceException
+     */
+    public function setBody(mixed $body): void
+    {
+        $this->setAddress($body);
+    }
+
+    /**
+     * @throws RfcComplianceException
+     */
+    public function getBody(): Address
+    {
+        return $this->getAddress();
+    }
+
+    /**
+     * @throws RfcComplianceException
+     */
+    public function setAddress(Address $address): void
+    {
+        $this->address = $address;
+    }
+
+    public function getAddress(): Address
+    {
+        return $this->address;
+    }
+
+    public function getBodyAsString(): string
+    {
+        $str = $this->address->getEncodedAddress();
+        if ($name = $this->address->getName()) {
+            $str = $this->createPhrase($this, $name, $this->getCharset(), true).' <'.$str.'>';
+        }
+
+        return $str;
+    }
+
+    /**
+     * Redefine the encoding requirements for an address.
+     *
+     * All "specials" must be encoded as the full header value will not be quoted
+     *
+     * @see RFC 2822 3.2.1
+     */
+    protected function tokenNeedsEncoding(string $token): bool
+    {
+        return preg_match('/[()<>\[\]:;@\,."]/', $token) || parent::tokenNeedsEncoding($token);
+    }
+}

lib/symfony/mime/Header/MailboxListHeader.php

@@ -0,0 +1,136 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Exception\RfcComplianceException;
+
+/**
+ * A Mailbox list MIME Header for something like From, To, Cc, and Bcc (one or more named addresses).
+ *
+ * @author Chris Corbyn
+ */
+final class MailboxListHeader extends AbstractHeader
+{
+    private array $addresses = [];
+
+    /**
+     * @param Address[] $addresses
+     */
+    public function __construct(string $name, array $addresses)
+    {
+        parent::__construct($name);
+
+        $this->setAddresses($addresses);
+    }
+
+    /**
+     * @param Address[] $body
+     *
+     * @throws RfcComplianceException
+     */
+    public function setBody(mixed $body): void
+    {
+        $this->setAddresses($body);
+    }
+
+    /**
+     * @return Address[]
+     *
+     * @throws RfcComplianceException
+     */
+    public function getBody(): array
+    {
+        return $this->getAddresses();
+    }
+
+    /**
+     * Sets a list of addresses to be shown in this Header.
+     *
+     * @param Address[] $addresses
+     *
+     * @throws RfcComplianceException
+     */
+    public function setAddresses(array $addresses): void
+    {
+        $this->addresses = [];
+        $this->addAddresses($addresses);
+    }
+
+    /**
+     * Sets a list of addresses to be shown in this Header.
+     *
+     * @param Address[] $addresses
+     *
+     * @throws RfcComplianceException
+     */
+    public function addAddresses(array $addresses): void
+    {
+        foreach ($addresses as $address) {
+            $this->addAddress($address);
+        }
+    }
+
+    /**
+     * @throws RfcComplianceException
+     */
+    public function addAddress(Address $address): void
+    {
+        $this->addresses[] = $address;
+    }
+
+    /**
+     * @return Address[]
+     */
+    public function getAddresses(): array
+    {
+        return $this->addresses;
+    }
+
+    /**
+     * Gets the full mailbox list of this Header as an array of valid RFC 2822 strings.
+     *
+     * @return string[]
+     *
+     * @throws RfcComplianceException
+     */
+    public function getAddressStrings(): array
+    {
+        $strings = [];
+        foreach ($this->addresses as $address) {
+            $str = $address->getEncodedAddress();
+            if ($name = $address->getName()) {
+                $str = $this->createPhrase($this, $name, $this->getCharset(), !$strings).' <'.$str.'>';
+            }
+            $strings[] = $str;
+        }
+
+        return $strings;
+    }
+
+    public function getBodyAsString(): string
+    {
+        return implode(', ', $this->getAddressStrings());
+    }
+
+    /**
+     * Redefine the encoding requirements for addresses.
+     *
+     * All "specials" must be encoded as the full header value will not be quoted
+     *
+     * @see RFC 2822 3.2.1
+     */
+    protected function tokenNeedsEncoding(string $token): bool
+    {
+        return preg_match('/[()<>\[\]:;@\,."]/', $token) || parent::tokenNeedsEncoding($token);
+    }
+}

lib/symfony/mime/Header/ParameterizedHeader.php

@@ -0,0 +1,191 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Encoder\Rfc2231Encoder;
+
+/**
+ * @author Chris Corbyn
+ */
+final class ParameterizedHeader extends UnstructuredHeader
+{
+    /**
+     * RFC 2231's definition of a token.
+     *
+     * @var string
+     */
+    public const TOKEN_REGEX = '(?:[\x21\x23-\x27\x2A\x2B\x2D\x2E\x30-\x39\x41-\x5A\x5E-\x7E]+)';
+
+    private ?Rfc2231Encoder $encoder = null;
+    private array $parameters = [];
+
+    public function __construct(string $name, string $value, array $parameters = [])
+    {
+        parent::__construct($name, $value);
+
+        foreach ($parameters as $k => $v) {
+            $this->setParameter($k, $v);
+        }
+
+        if ('content-type' !== strtolower($name)) {
+            $this->encoder = new Rfc2231Encoder();
+        }
+    }
+
+    public function setParameter(string $parameter, ?string $value): void
+    {
+        $this->setParameters(array_merge($this->getParameters(), [$parameter => $value]));
+    }
+
+    public function getParameter(string $parameter): string
+    {
+        return $this->getParameters()[$parameter] ?? '';
+    }
+
+    /**
+     * @param string[] $parameters
+     */
+    public function setParameters(array $parameters): void
+    {
+        $this->parameters = $parameters;
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getParameters(): array
+    {
+        return $this->parameters;
+    }
+
+    public function getBodyAsString(): string
+    {
+        $body = parent::getBodyAsString();
+        foreach ($this->parameters as $name => $value) {
+            if (null !== $value) {
+                $body .= '; '.$this->createParameter($name, $value);
+            }
+        }
+
+        return $body;
+    }
+
+    /**
+     * Generate a list of all tokens in the final header.
+     *
+     * This doesn't need to be overridden in theory, but it is for implementation
+     * reasons to prevent potential breakage of attributes.
+     */
+    protected function toTokens(?string $string = null): array
+    {
+        $tokens = parent::toTokens(parent::getBodyAsString());
+
+        // Try creating any parameters
+        foreach ($this->parameters as $name => $value) {
+            if (null !== $value) {
+                // Add the semi-colon separator
+                $tokens[\count($tokens) - 1] .= ';';
+                $tokens = array_merge($tokens, $this->generateTokenLines(' '.$this->createParameter($name, $value)));
+            }
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Render an RFC 2047 compliant header parameter from the $name and $value.
+     */
+    private function createParameter(string $name, string $value): string
+    {
+        $origValue = $value;
+
+        $encoded = false;
+        // Allow room for parameter name, indices, "=" and DQUOTEs
+        $maxValueLength = $this->getMaxLineLength() - \strlen($name.'=*N"";') - 1;
+        $firstLineOffset = 0;
+
+        // If it's not already a valid parameter value...
+        if (!preg_match('/^'.self::TOKEN_REGEX.'$/D', $value)) {
+            // TODO: text, or something else??
+            // ... and it's not ascii
+            if (!preg_match('/^[\x00-\x08\x0B\x0C\x0E-\x7F]*$/D', $value)) {
+                $encoded = true;
+                // Allow space for the indices, charset and language
+                $maxValueLength = $this->getMaxLineLength() - \strlen($name.'*N*="";') - 1;
+                $firstLineOffset = \strlen($this->getCharset()."'".$this->getLanguage()."'");
+            }
+
+            if (\in_array($name, ['name', 'filename'], true) && 'form-data' === $this->getValue() && 'content-disposition' === strtolower($this->getName()) && preg_match('//u', $value)) {
+                // WHATWG HTML living standard 4.10.21.8 2 specifies:
+                // For field names and filenames for file fields, the result of the
+                // encoding in the previous bullet point must be escaped by replacing
+                // any 0x0A (LF) bytes with the byte sequence `%0A`, 0x0D (CR) with `%0D`
+                // and 0x22 (") with `%22`.
+                // The user agent must not perform any other escapes.
+                $value = str_replace(['"', "\r", "\n"], ['%22', '%0D', '%0A'], $value);
+
+                if (\strlen($value) <= $maxValueLength) {
+                    return $name.'="'.$value.'"';
+                }
+
+                $value = $origValue;
+            }
+        }
+
+        // Encode if we need to
+        if ($encoded || \strlen($value) > $maxValueLength) {
+            if (null !== $this->encoder) {
+                $value = $this->encoder->encodeString($origValue, $this->getCharset(), $firstLineOffset, $maxValueLength);
+            } else {
+                // We have to go against RFC 2183/2231 in some areas for interoperability
+                $value = $this->getTokenAsEncodedWord($origValue);
+                $encoded = false;
+            }
+        }
+
+        $valueLines = $this->encoder ? explode("\r\n", $value) : [$value];
+
+        // Need to add indices
+        if (\count($valueLines) > 1) {
+            $paramLines = [];
+            foreach ($valueLines as $i => $line) {
+                $paramLines[] = $name.'*'.$i.$this->getEndOfParameterValue($line, true, 0 === $i);
+            }
+
+            return implode(";\r\n ", $paramLines);
+        } else {
+            return $name.$this->getEndOfParameterValue($valueLines[0], $encoded, true);
+        }
+    }
+
+    /**
+     * Returns the parameter value from the "=" and beyond.
+     *
+     * @param string $value to append
+     */
+    private function getEndOfParameterValue(string $value, bool $encoded = false, bool $firstLine = false): string
+    {
+        $forceHttpQuoting = 'form-data' === $this->getValue() && 'content-disposition' === strtolower($this->getName());
+        if ($forceHttpQuoting || !preg_match('/^'.self::TOKEN_REGEX.'$/D', $value)) {
+            $value = '"'.$value.'"';
+        }
+        $prepend = '=';
+        if ($encoded) {
+            $prepend = '*=';
+            if ($firstLine) {
+                $prepend = '*='.$this->getCharset()."'".$this->getLanguage()."'";
+            }
+        }
+
+        return $prepend.$value;
+    }
+}

lib/symfony/mime/Header/PathHeader.php

@@ -0,0 +1,62 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Exception\RfcComplianceException;
+
+/**
+ * A Path Header, such a Return-Path (one address).
+ *
+ * @author Chris Corbyn
+ */
+final class PathHeader extends AbstractHeader
+{
+    private Address $address;
+
+    public function __construct(string $name, Address $address)
+    {
+        parent::__construct($name);
+
+        $this->setAddress($address);
+    }
+
+    /**
+     * @param Address $body
+     *
+     * @throws RfcComplianceException
+     */
+    public function setBody(mixed $body): void
+    {
+        $this->setAddress($body);
+    }
+
+    public function getBody(): Address
+    {
+        return $this->getAddress();
+    }
+
+    public function setAddress(Address $address): void
+    {
+        $this->address = $address;
+    }
+
+    public function getAddress(): Address
+    {
+        return $this->address;
+    }
+
+    public function getBodyAsString(): string
+    {
+        return '<'.$this->address->getEncodedAddress().'>';
+    }
+}

lib/symfony/mime/Header/UnstructuredHeader.php

@@ -0,0 +1,70 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Header;
+
+/**
+ * A Simple MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+class UnstructuredHeader extends AbstractHeader
+{
+    private string $value;
+
+    public function __construct(string $name, string $value)
+    {
+        parent::__construct($name);
+
+        $this->setValue($value);
+    }
+
+    /**
+     * @param string $body
+     *
+     * @return void
+     */
+    public function setBody(mixed $body)
+    {
+        $this->setValue($body);
+    }
+
+    public function getBody(): string
+    {
+        return $this->getValue();
+    }
+
+    /**
+     * Get the (unencoded) value of this header.
+     */
+    public function getValue(): string
+    {
+        return $this->value;
+    }
+
+    /**
+     * Set the (unencoded) value of this header.
+     *
+     * @return void
+     */
+    public function setValue(string $value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * Get the value of this header prepared for rendering.
+     */
+    public function getBodyAsString(): string
+    {
+        return $this->encodeWords($this, $this->value);
+    }
+}

lib/symfony/mime/HtmlToTextConverter/DefaultHtmlToTextConverter.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\HtmlToTextConverter;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class DefaultHtmlToTextConverter implements HtmlToTextConverterInterface
+{
+    public function convert(string $html, string $charset): string
+    {
+        return strip_tags(preg_replace('{<(head|style)\b.*?</\1>}is', '', $html));
+    }
+}

lib/symfony/mime/HtmlToTextConverter/HtmlToTextConverterInterface.php

@@ -0,0 +1,25 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\HtmlToTextConverter;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface HtmlToTextConverterInterface
+{
+    /**
+     * Converts an HTML representation of a Message to a text representation.
+     *
+     * The output must use the same charset as the HTML one.
+     */
+    public function convert(string $html, string $charset): string;
+}

lib/symfony/mime/HtmlToTextConverter/LeagueHtmlToMarkdownConverter.php

@@ -0,0 +1,35 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\HtmlToTextConverter;
+
+use League\HTMLToMarkdown\HtmlConverter;
+use League\HTMLToMarkdown\HtmlConverterInterface;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class LeagueHtmlToMarkdownConverter implements HtmlToTextConverterInterface
+{
+    public function __construct(
+        private HtmlConverterInterface $converter = new HtmlConverter([
+            'hard_break' => true,
+            'strip_tags' => true,
+            'remove_nodes' => 'head style',
+        ]),
+    ) {
+    }
+
+    public function convert(string $html, string $charset): string
+    {
+        return $this->converter->convert($html);
+    }
+}

lib/symfony/mime/Message.php

@@ -0,0 +1,169 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\LogicException;
+use Symfony\Component\Mime\Header\Headers;
+use Symfony\Component\Mime\Part\AbstractPart;
+use Symfony\Component\Mime\Part\TextPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Message extends RawMessage
+{
+    private Headers $headers;
+    private ?AbstractPart $body;
+
+    public function __construct(?Headers $headers = null, ?AbstractPart $body = null)
+    {
+        $this->headers = $headers ? clone $headers : new Headers();
+        $this->body = $body;
+    }
+
+    public function __clone()
+    {
+        $this->headers = clone $this->headers;
+
+        if (null !== $this->body) {
+            $this->body = clone $this->body;
+        }
+    }
+
+    /**
+     * @return $this
+     */
+    public function setBody(?AbstractPart $body = null): static
+    {
+        if (1 > \func_num_args()) {
+            trigger_deprecation('symfony/mime', '6.2', 'Calling "%s()" without any arguments is deprecated, pass null explicitly instead.', __METHOD__);
+        }
+        $this->body = $body;
+
+        return $this;
+    }
+
+    public function getBody(): ?AbstractPart
+    {
+        return $this->body;
+    }
+
+    /**
+     * @return $this
+     */
+    public function setHeaders(Headers $headers): static
+    {
+        $this->headers = $headers;
+
+        return $this;
+    }
+
+    public function getHeaders(): Headers
+    {
+        return $this->headers;
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = clone $this->headers;
+
+        if (!$headers->has('From')) {
+            if (!$headers->has('Sender')) {
+                throw new LogicException('An email must have a "From" or a "Sender" header.');
+            }
+            $headers->addMailboxListHeader('From', [$headers->get('Sender')->getAddress()]);
+        }
+
+        if (!$headers->has('MIME-Version')) {
+            $headers->addTextHeader('MIME-Version', '1.0');
+        }
+
+        if (!$headers->has('Date')) {
+            $headers->addDateHeader('Date', new \DateTimeImmutable());
+        }
+
+        // determine the "real" sender
+        if (!$headers->has('Sender') && \count($froms = $headers->get('From')->getAddresses()) > 1) {
+            $headers->addMailboxHeader('Sender', $froms[0]);
+        }
+
+        if (!$headers->has('Message-ID')) {
+            $headers->addIdHeader('Message-ID', $this->generateMessageId());
+        }
+
+        // remove the Bcc field which should NOT be part of the sent message
+        $headers->remove('Bcc');
+
+        return $headers;
+    }
+
+    public function toString(): string
+    {
+        if (null === $body = $this->getBody()) {
+            $body = new TextPart('');
+        }
+
+        return $this->getPreparedHeaders()->toString().$body->toString();
+    }
+
+    public function toIterable(): iterable
+    {
+        if (null === $body = $this->getBody()) {
+            $body = new TextPart('');
+        }
+
+        yield $this->getPreparedHeaders()->toString();
+        yield from $body->toIterable();
+    }
+
+    /**
+     * @return void
+     */
+    public function ensureValidity()
+    {
+        if (!$this->headers->get('To')?->getBody() && !$this->headers->get('Cc')?->getBody() && !$this->headers->get('Bcc')?->getBody()) {
+            throw new LogicException('An email must have a "To", "Cc", or "Bcc" header.');
+        }
+
+        if (!$this->headers->get('From')?->getBody() && !$this->headers->get('Sender')?->getBody()) {
+            throw new LogicException('An email must have a "From" or a "Sender" header.');
+        }
+
+        parent::ensureValidity();
+    }
+
+    public function generateMessageId(): string
+    {
+        if ($this->headers->has('Sender')) {
+            $sender = $this->headers->get('Sender')->getAddress();
+        } elseif ($this->headers->has('From')) {
+            if (!$froms = $this->headers->get('From')->getAddresses()) {
+                throw new LogicException('A "From" header must have at least one email address.');
+            }
+            $sender = $froms[0];
+        } else {
+            throw new LogicException('An email must have a "From" or a "Sender" header.');
+        }
+
+        return bin2hex(random_bytes(16)).strstr($sender->getAddress(), '@');
+    }
+
+    public function __serialize(): array
+    {
+        return [$this->headers, $this->body];
+    }
+
+    public function __unserialize(array $data): void
+    {
+        [$this->headers, $this->body] = $data;
+    }
+}

lib/symfony/mime/MessageConverter.php

@@ -0,0 +1,122 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\RuntimeException;
+use Symfony\Component\Mime\Part\DataPart;
+use Symfony\Component\Mime\Part\Multipart\AlternativePart;
+use Symfony\Component\Mime\Part\Multipart\MixedPart;
+use Symfony\Component\Mime\Part\Multipart\RelatedPart;
+use Symfony\Component\Mime\Part\TextPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class MessageConverter
+{
+    /**
+     * @throws RuntimeException when unable to convert the message to an email
+     */
+    public static function toEmail(Message $message): Email
+    {
+        if ($message instanceof Email) {
+            return $message;
+        }
+
+        // try to convert to a "simple" Email instance
+        $body = $message->getBody();
+        if ($body instanceof TextPart) {
+            return self::createEmailFromTextPart($message, $body);
+        }
+
+        if ($body instanceof AlternativePart) {
+            return self::createEmailFromAlternativePart($message, $body);
+        }
+
+        if ($body instanceof RelatedPart) {
+            return self::createEmailFromRelatedPart($message, $body);
+        }
+
+        if ($body instanceof MixedPart) {
+            $parts = $body->getParts();
+            if ($parts[0] instanceof RelatedPart) {
+                $email = self::createEmailFromRelatedPart($message, $parts[0]);
+            } elseif ($parts[0] instanceof AlternativePart) {
+                $email = self::createEmailFromAlternativePart($message, $parts[0]);
+            } elseif ($parts[0] instanceof TextPart) {
+                $email = self::createEmailFromTextPart($message, $parts[0]);
+            } else {
+                throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($message)));
+            }
+
+            return self::addParts($email, \array_slice($parts, 1));
+        }
+
+        throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($message)));
+    }
+
+    private static function createEmailFromTextPart(Message $message, TextPart $part): Email
+    {
+        if ('text' === $part->getMediaType() && 'plain' === $part->getMediaSubtype()) {
+            return (new Email(clone $message->getHeaders()))->text($part->getBody(), $part->getPreparedHeaders()->getHeaderParameter('Content-Type', 'charset') ?: 'utf-8');
+        }
+        if ('text' === $part->getMediaType() && 'html' === $part->getMediaSubtype()) {
+            return (new Email(clone $message->getHeaders()))->html($part->getBody(), $part->getPreparedHeaders()->getHeaderParameter('Content-Type', 'charset') ?: 'utf-8');
+        }
+
+        throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($message)));
+    }
+
+    private static function createEmailFromAlternativePart(Message $message, AlternativePart $part): Email
+    {
+        $parts = $part->getParts();
+        if (
+            2 === \count($parts)
+            && $parts[0] instanceof TextPart && 'text' === $parts[0]->getMediaType() && 'plain' === $parts[0]->getMediaSubtype()
+            && $parts[1] instanceof TextPart && 'text' === $parts[1]->getMediaType() && 'html' === $parts[1]->getMediaSubtype()
+        ) {
+            return (new Email(clone $message->getHeaders()))
+                ->text($parts[0]->getBody(), $parts[0]->getPreparedHeaders()->getHeaderParameter('Content-Type', 'charset') ?: 'utf-8')
+                ->html($parts[1]->getBody(), $parts[1]->getPreparedHeaders()->getHeaderParameter('Content-Type', 'charset') ?: 'utf-8')
+            ;
+        }
+
+        throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($message)));
+    }
+
+    private static function createEmailFromRelatedPart(Message $message, RelatedPart $part): Email
+    {
+        $parts = $part->getParts();
+        if ($parts[0] instanceof AlternativePart) {
+            $email = self::createEmailFromAlternativePart($message, $parts[0]);
+        } elseif ($parts[0] instanceof TextPart) {
+            $email = self::createEmailFromTextPart($message, $parts[0]);
+        } else {
+            throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($message)));
+        }
+
+        return self::addParts($email, \array_slice($parts, 1));
+    }
+
+    private static function addParts(Email $email, array $parts): Email
+    {
+        foreach ($parts as $part) {
+            if (!$part instanceof DataPart) {
+                throw new RuntimeException(\sprintf('Unable to create an Email from an instance of "%s" as the body is too complex.', get_debug_type($email)));
+            }
+
+            $email->addPart($part);
+        }
+
+        return $email;
+    }
+}

lib/symfony/mime/MimeTypeGuesserInterface.php

@@ -0,0 +1,33 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+/**
+ * Guesses the MIME type of a file.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface MimeTypeGuesserInterface
+{
+    /**
+     * Returns true if this guesser is supported.
+     */
+    public function isGuesserSupported(): bool;
+
+    /**
+     * Guesses the MIME type of the file with the given path.
+     *
+     * @throws \LogicException           If the guesser is not supported
+     * @throws \InvalidArgumentException If the file does not exist or is not readable
+     */
+    public function guessMimeType(string $path): ?string;
+}

lib/symfony/mime/MimeTypesInterface.php

@@ -0,0 +1,32 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface MimeTypesInterface extends MimeTypeGuesserInterface
+{
+    /**
+     * Gets the extensions for the given MIME type in decreasing order of preference.
+     *
+     * @return string[]
+     */
+    public function getExtensions(string $mimeType): array;
+
+    /**
+     * Gets the MIME types for the given extension in decreasing order of preference.
+     *
+     * @return string[]
+     */
+    public function getMimeTypes(string $ext): array;
+}

lib/symfony/mime/Part/AbstractMultipartPart.php

@@ -0,0 +1,95 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Header\Headers;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+abstract class AbstractMultipartPart extends AbstractPart
+{
+    private ?string $boundary = null;
+    private array $parts = [];
+
+    public function __construct(AbstractPart ...$parts)
+    {
+        parent::__construct();
+
+        foreach ($parts as $part) {
+            $this->parts[] = $part;
+        }
+    }
+
+    /**
+     * @return AbstractPart[]
+     */
+    public function getParts(): array
+    {
+        return $this->parts;
+    }
+
+    public function getMediaType(): string
+    {
+        return 'multipart';
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = parent::getPreparedHeaders();
+        $headers->setHeaderParameter('Content-Type', 'boundary', $this->getBoundary());
+
+        return $headers;
+    }
+
+    public function bodyToString(): string
+    {
+        $parts = $this->getParts();
+        $string = '';
+        foreach ($parts as $part) {
+            $string .= '--'.$this->getBoundary()."\r\n".$part->toString()."\r\n";
+        }
+        $string .= '--'.$this->getBoundary()."--\r\n";
+
+        return $string;
+    }
+
+    public function bodyToIterable(): iterable
+    {
+        $parts = $this->getParts();
+        foreach ($parts as $part) {
+            yield '--'.$this->getBoundary()."\r\n";
+            yield from $part->toIterable();
+            yield "\r\n";
+        }
+        yield '--'.$this->getBoundary()."--\r\n";
+    }
+
+    public function asDebugString(): string
+    {
+        $str = parent::asDebugString();
+        foreach ($this->getParts() as $part) {
+            $lines = explode("\n", $part->asDebugString());
+            $str .= "\n  └ ".array_shift($lines);
+            foreach ($lines as $line) {
+                $str .= "\n  |".$line;
+            }
+        }
+
+        return $str;
+    }
+
+    private function getBoundary(): string
+    {
+        return $this->boundary ??= strtr(base64_encode(random_bytes(6)), '+/', '-_');
+    }
+}

lib/symfony/mime/Part/AbstractPart.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Header\Headers;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+abstract class AbstractPart
+{
+    private Headers $headers;
+
+    public function __construct()
+    {
+        $this->headers = new Headers();
+    }
+
+    public function getHeaders(): Headers
+    {
+        return $this->headers;
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = clone $this->headers;
+        $headers->setHeaderBody('Parameterized', 'Content-Type', $this->getMediaType().'/'.$this->getMediaSubtype());
+
+        return $headers;
+    }
+
+    public function toString(): string
+    {
+        return $this->getPreparedHeaders()->toString()."\r\n".$this->bodyToString();
+    }
+
+    public function toIterable(): iterable
+    {
+        yield $this->getPreparedHeaders()->toString();
+        yield "\r\n";
+        yield from $this->bodyToIterable();
+    }
+
+    public function asDebugString(): string
+    {
+        return $this->getMediaType().'/'.$this->getMediaSubtype();
+    }
+
+    abstract public function bodyToString(): string;
+
+    abstract public function bodyToIterable(): iterable;
+
+    abstract public function getMediaType(): string;
+
+    abstract public function getMediaSubtype(): string;
+}

lib/symfony/mime/Part/DataPart.php

@@ -0,0 +1,168 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Header\Headers;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class DataPart extends TextPart
+{
+    /** @internal */
+    protected array $_parent;
+
+    private ?string $filename = null;
+    private string $mediaType;
+    private ?string $cid = null;
+
+    /**
+     * @param resource|string|File $body Use a File instance to defer loading the file until rendering
+     */
+    public function __construct($body, ?string $filename = null, ?string $contentType = null, ?string $encoding = null)
+    {
+        if ($body instanceof File && !$filename) {
+            $filename = $body->getFilename();
+        }
+
+        $contentType ??= $body instanceof File ? $body->getContentType() : 'application/octet-stream';
+        [$this->mediaType, $subtype] = explode('/', $contentType);
+
+        parent::__construct($body, null, $subtype, $encoding);
+
+        if (null !== $filename) {
+            $this->filename = $filename;
+            $this->setName($filename);
+        }
+        $this->setDisposition('attachment');
+    }
+
+    public static function fromPath(string $path, ?string $name = null, ?string $contentType = null): self
+    {
+        return new self(new File($path), $name, $contentType);
+    }
+
+    /**
+     * @return $this
+     */
+    public function asInline(): static
+    {
+        return $this->setDisposition('inline');
+    }
+
+    /**
+     * @return $this
+     */
+    public function setContentId(string $cid): static
+    {
+        if (!str_contains($cid, '@')) {
+            throw new InvalidArgumentException(\sprintf('Invalid cid "%s".', $cid));
+        }
+
+        $this->cid = $cid;
+
+        return $this;
+    }
+
+    public function getContentId(): string
+    {
+        return $this->cid ?: $this->cid = $this->generateContentId();
+    }
+
+    public function hasContentId(): bool
+    {
+        return null !== $this->cid;
+    }
+
+    public function getMediaType(): string
+    {
+        return $this->mediaType;
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = parent::getPreparedHeaders();
+
+        if (null !== $this->cid) {
+            $headers->setHeaderBody('Id', 'Content-ID', $this->cid);
+        }
+
+        if (null !== $this->filename) {
+            $headers->setHeaderParameter('Content-Disposition', 'filename', $this->filename);
+        }
+
+        return $headers;
+    }
+
+    public function asDebugString(): string
+    {
+        $str = parent::asDebugString();
+        if (null !== $this->filename) {
+            $str .= ' filename: '.$this->filename;
+        }
+
+        return $str;
+    }
+
+    public function getFilename(): ?string
+    {
+        return $this->filename;
+    }
+
+    public function getContentType(): string
+    {
+        return implode('/', [$this->getMediaType(), $this->getMediaSubtype()]);
+    }
+
+    private function generateContentId(): string
+    {
+        return bin2hex(random_bytes(16)).'@symfony';
+    }
+
+    public function __sleep(): array
+    {
+        // converts the body to a string
+        parent::__sleep();
+
+        $this->_parent = [];
+        foreach (['body', 'charset', 'subtype', 'disposition', 'name', 'encoding'] as $name) {
+            $r = new \ReflectionProperty(TextPart::class, $name);
+            $this->_parent[$name] = $r->getValue($this);
+        }
+        $this->_headers = $this->getHeaders();
+
+        return ['_headers', '_parent', 'filename', 'mediaType'];
+    }
+
+    /**
+     * @return void
+     */
+    public function __wakeup()
+    {
+        $r = new \ReflectionProperty(AbstractPart::class, 'headers');
+        $r->setValue($this, $this->_headers);
+        unset($this->_headers);
+
+        if (!\is_array($this->_parent)) {
+            throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+        }
+        foreach (['body', 'charset', 'subtype', 'disposition', 'name', 'encoding'] as $name) {
+            if (null !== $this->_parent[$name] && !\is_string($this->_parent[$name]) && !$this->_parent[$name] instanceof File) {
+                throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+            }
+            $r = new \ReflectionProperty(TextPart::class, $name);
+            $r->setValue($this, $this->_parent[$name]);
+        }
+        unset($this->_parent);
+    }
+}

lib/symfony/mime/Part/File.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\MimeTypes;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class File
+{
+    private static MimeTypes $mimeTypes;
+
+    public function __construct(
+        private string $path,
+        private ?string $filename = null,
+    ) {
+    }
+
+    public function getPath(): string
+    {
+        return $this->path;
+    }
+
+    public function getContentType(): string
+    {
+        $ext = strtolower(pathinfo($this->path, \PATHINFO_EXTENSION));
+        self::$mimeTypes ??= new MimeTypes();
+
+        return self::$mimeTypes->getMimeTypes($ext)[0] ?? 'application/octet-stream';
+    }
+
+    public function getSize(): int
+    {
+        return filesize($this->path);
+    }
+
+    public function getFilename(): string
+    {
+        return $this->filename ??= basename($this->getPath());
+    }
+}

lib/symfony/mime/Part/MessagePart.php

@@ -0,0 +1,72 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Message;
+use Symfony\Component\Mime\RawMessage;
+
+/**
+ * @final
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class MessagePart extends DataPart
+{
+    private RawMessage $message;
+
+    public function __construct(RawMessage $message)
+    {
+        if ($message instanceof Message) {
+            $name = $message->getHeaders()->getHeaderBody('Subject').'.eml';
+        } else {
+            $name = 'email.eml';
+        }
+        parent::__construct('', $name);
+
+        $this->message = $message;
+    }
+
+    public function getMediaType(): string
+    {
+        return 'message';
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return 'rfc822';
+    }
+
+    public function getBody(): string
+    {
+        return $this->message->toString();
+    }
+
+    public function bodyToString(): string
+    {
+        return $this->getBody();
+    }
+
+    public function bodyToIterable(): iterable
+    {
+        return $this->message->toIterable();
+    }
+
+    public function __sleep(): array
+    {
+        return ['message'];
+    }
+
+    public function __wakeup(): void
+    {
+        $this->__construct($this->message);
+    }
+}

lib/symfony/mime/Part/Multipart/AlternativePart.php

@@ -0,0 +1,25 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part\Multipart;
+
+use Symfony\Component\Mime\Part\AbstractMultipartPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class AlternativePart extends AbstractMultipartPart
+{
+    public function getMediaSubtype(): string
+    {
+        return 'alternative';
+    }
+}

lib/symfony/mime/Part/Multipart/DigestPart.php

@@ -0,0 +1,31 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part\Multipart;
+
+use Symfony\Component\Mime\Part\AbstractMultipartPart;
+use Symfony\Component\Mime\Part\MessagePart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class DigestPart extends AbstractMultipartPart
+{
+    public function __construct(MessagePart ...$parts)
+    {
+        parent::__construct(...$parts);
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return 'digest';
+    }
+}

lib/symfony/mime/Part/Multipart/FormDataPart.php

@@ -0,0 +1,107 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part\Multipart;
+
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Part\AbstractMultipartPart;
+use Symfony\Component\Mime\Part\TextPart;
+
+/**
+ * Implements RFC 7578.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class FormDataPart extends AbstractMultipartPart
+{
+    private array $fields = [];
+
+    /**
+     * @param array<string|array|TextPart> $fields
+     */
+    public function __construct(array $fields = [])
+    {
+        parent::__construct();
+
+        $this->fields = $fields;
+
+        // HTTP does not support \r\n in header values
+        $this->getHeaders()->setMaxLineLength(\PHP_INT_MAX);
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return 'form-data';
+    }
+
+    public function getParts(): array
+    {
+        return $this->prepareFields($this->fields);
+    }
+
+    private function prepareFields(array $fields): array
+    {
+        $values = [];
+
+        $prepare = function ($item, $key, $root = null) use (&$values, &$prepare) {
+            if (null === $root && \is_int($key) && \is_array($item)) {
+                if (1 !== \count($item)) {
+                    throw new InvalidArgumentException(\sprintf('Form field values with integer keys can only have one array element, the key being the field name and the value being the field value, %d provided.', \count($item)));
+                }
+
+                $key = key($item);
+                $item = $item[$key];
+            }
+
+            $fieldName = null !== $root ? \sprintf('%s[%s]', $root, $key) : $key;
+
+            if (\is_array($item)) {
+                array_walk($item, $prepare, $fieldName);
+
+                return;
+            }
+
+            if (!\is_string($item) && !$item instanceof TextPart) {
+                throw new InvalidArgumentException(\sprintf('The value of the form field "%s" can only be a string, an array, or an instance of TextPart, "%s" given.', $fieldName, get_debug_type($item)));
+            }
+
+            $values[] = $this->preparePart($fieldName, $item);
+        };
+
+        array_walk($fields, $prepare);
+
+        return $values;
+    }
+
+    private function preparePart(string $name, string|TextPart $value): TextPart
+    {
+        if (\is_string($value)) {
+            return $this->configurePart($name, new TextPart($value, 'utf-8', 'plain', '8bit'));
+        }
+
+        return $this->configurePart($name, $value);
+    }
+
+    private function configurePart(string $name, TextPart $part): TextPart
+    {
+        static $r;
+
+        $r ??= new \ReflectionProperty(TextPart::class, 'encoding');
+
+        $part->setDisposition('form-data');
+        $part->setName($name);
+        // HTTP does not support \r\n in header values
+        $part->getHeaders()->setMaxLineLength(\PHP_INT_MAX);
+        $r->setValue($part, '8bit');
+
+        return $part;
+    }
+}

lib/symfony/mime/Part/Multipart/MixedPart.php

@@ -0,0 +1,25 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part\Multipart;
+
+use Symfony\Component\Mime\Part\AbstractMultipartPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class MixedPart extends AbstractMultipartPart
+{
+    public function getMediaSubtype(): string
+    {
+        return 'mixed';
+    }
+}

lib/symfony/mime/Part/Multipart/RelatedPart.php

@@ -0,0 +1,55 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part\Multipart;
+
+use Symfony\Component\Mime\Part\AbstractMultipartPart;
+use Symfony\Component\Mime\Part\AbstractPart;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class RelatedPart extends AbstractMultipartPart
+{
+    private AbstractPart $mainPart;
+
+    public function __construct(AbstractPart $mainPart, AbstractPart $part, AbstractPart ...$parts)
+    {
+        $this->mainPart = $mainPart;
+        $this->prepareParts($part, ...$parts);
+
+        parent::__construct($part, ...$parts);
+    }
+
+    public function getParts(): array
+    {
+        return array_merge([$this->mainPart], parent::getParts());
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return 'related';
+    }
+
+    private function generateContentId(): string
+    {
+        return bin2hex(random_bytes(16)).'@symfony';
+    }
+
+    private function prepareParts(AbstractPart ...$parts): void
+    {
+        foreach ($parts as $part) {
+            if (!$part->getHeaders()->has('Content-ID')) {
+                $part->getHeaders()->setHeaderBody('Id', 'Content-ID', $this->generateContentId());
+            }
+        }
+    }
+}

lib/symfony/mime/Part/SMimePart.php

@@ -0,0 +1,111 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Header\Headers;
+
+/**
+ * @author Sebastiaan Stok <s.stok@rollerscapes.net>
+ */
+class SMimePart extends AbstractPart
+{
+    /** @internal */
+    protected Headers $_headers;
+
+    private iterable|string $body;
+    private string $type;
+    private string $subtype;
+    private array $parameters;
+
+    public function __construct(iterable|string $body, string $type, string $subtype, array $parameters)
+    {
+        parent::__construct();
+
+        $this->body = $body;
+        $this->type = $type;
+        $this->subtype = $subtype;
+        $this->parameters = $parameters;
+    }
+
+    public function getMediaType(): string
+    {
+        return $this->type;
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return $this->subtype;
+    }
+
+    public function bodyToString(): string
+    {
+        if (\is_string($this->body)) {
+            return $this->body;
+        }
+
+        $body = '';
+        foreach ($this->body as $chunk) {
+            $body .= $chunk;
+        }
+        $this->body = $body;
+
+        return $body;
+    }
+
+    public function bodyToIterable(): iterable
+    {
+        if (\is_string($this->body)) {
+            yield $this->body;
+
+            return;
+        }
+
+        $body = '';
+        foreach ($this->body as $chunk) {
+            $body .= $chunk;
+            yield $chunk;
+        }
+        $this->body = $body;
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = clone parent::getHeaders();
+
+        $headers->setHeaderBody('Parameterized', 'Content-Type', $this->getMediaType().'/'.$this->getMediaSubtype());
+
+        foreach ($this->parameters as $name => $value) {
+            $headers->setHeaderParameter('Content-Type', $name, $value);
+        }
+
+        return $headers;
+    }
+
+    public function __sleep(): array
+    {
+        // convert iterables to strings for serialization
+        if (is_iterable($this->body)) {
+            $this->body = $this->bodyToString();
+        }
+
+        $this->_headers = $this->getHeaders();
+
+        return ['_headers', 'body', 'type', 'subtype', 'parameters'];
+    }
+
+    public function __wakeup(): void
+    {
+        $r = new \ReflectionProperty(AbstractPart::class, 'headers');
+        $r->setValue($this, $this->_headers);
+        unset($this->_headers);
+    }
+}

lib/symfony/mime/Part/TextPart.php

@@ -0,0 +1,248 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime\Part;
+
+use Symfony\Component\Mime\Encoder\Base64ContentEncoder;
+use Symfony\Component\Mime\Encoder\ContentEncoderInterface;
+use Symfony\Component\Mime\Encoder\EightBitContentEncoder;
+use Symfony\Component\Mime\Encoder\QpContentEncoder;
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
+use Symfony\Component\Mime\Header\Headers;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class TextPart extends AbstractPart
+{
+    /** @internal */
+    protected Headers $_headers;
+
+    private static array $encoders = [];
+
+    /** @var resource|string|File */
+    private $body;
+    private ?string $charset;
+    private string $subtype;
+    private ?string $disposition = null;
+    private ?string $name = null;
+    private string $encoding;
+    private ?bool $seekable = null;
+
+    /**
+     * @param resource|string|File $body Use a File instance to defer loading the file until rendering
+     */
+    public function __construct($body, ?string $charset = 'utf-8', string $subtype = 'plain', ?string $encoding = null)
+    {
+        parent::__construct();
+
+        if (!\is_string($body) && !\is_resource($body) && !$body instanceof File) {
+            throw new \TypeError(\sprintf('The body of "%s" must be a string, a resource, or an instance of "%s" (got "%s").', self::class, File::class, get_debug_type($body)));
+        }
+
+        if ($body instanceof File) {
+            $path = $body->getPath();
+            if ((is_file($path) && !is_readable($path)) || is_dir($path)) {
+                throw new InvalidArgumentException(\sprintf('Path "%s" is not readable.', $path));
+            }
+        }
+
+        $this->body = $body;
+        $this->charset = $charset;
+        $this->subtype = $subtype;
+        $this->seekable = \is_resource($body) ? stream_get_meta_data($body)['seekable'] && 0 === fseek($body, 0, \SEEK_CUR) : null;
+
+        if (null === $encoding) {
+            $this->encoding = $this->chooseEncoding();
+        } else {
+            if ('quoted-printable' !== $encoding && 'base64' !== $encoding && '8bit' !== $encoding) {
+                throw new InvalidArgumentException(\sprintf('The encoding must be one of "quoted-printable", "base64", or "8bit" ("%s" given).', $encoding));
+            }
+            $this->encoding = $encoding;
+        }
+    }
+
+    public function getMediaType(): string
+    {
+        return 'text';
+    }
+
+    public function getMediaSubtype(): string
+    {
+        return $this->subtype;
+    }
+
+    /**
+     * @param string $disposition one of attachment, inline, or form-data
+     *
+     * @return $this
+     */
+    public function setDisposition(string $disposition): static
+    {
+        $this->disposition = $disposition;
+
+        return $this;
+    }
+
+    /**
+     * @return ?string null or one of attachment, inline, or form-data
+     */
+    public function getDisposition(): ?string
+    {
+        return $this->disposition;
+    }
+
+    /**
+     * Sets the name of the file (used by FormDataPart).
+     *
+     * @return $this
+     */
+    public function setName(string $name): static
+    {
+        $this->name = $name;
+
+        return $this;
+    }
+
+    /**
+     * Gets the name of the file.
+     */
+    public function getName(): ?string
+    {
+        return $this->name;
+    }
+
+    public function getBody(): string
+    {
+        if ($this->body instanceof File) {
+            if (false === $ret = @file_get_contents($this->body->getPath())) {
+                throw new InvalidArgumentException(error_get_last()['message']);
+            }
+
+            return $ret;
+        }
+
+        if (null === $this->seekable) {
+            return $this->body;
+        }
+
+        if ($this->seekable) {
+            rewind($this->body);
+        }
+
+        return stream_get_contents($this->body) ?: '';
+    }
+
+    public function bodyToString(): string
+    {
+        return $this->getEncoder()->encodeString($this->getBody(), $this->charset);
+    }
+
+    public function bodyToIterable(): iterable
+    {
+        if ($this->body instanceof File) {
+            $path = $this->body->getPath();
+            if (false === $handle = @fopen($path, 'r', false)) {
+                throw new InvalidArgumentException(\sprintf('Unable to open path "%s".', $path));
+            }
+
+            yield from $this->getEncoder()->encodeByteStream($handle);
+        } elseif (null !== $this->seekable) {
+            if ($this->seekable) {
+                rewind($this->body);
+            }
+            yield from $this->getEncoder()->encodeByteStream($this->body);
+        } else {
+            yield $this->getEncoder()->encodeString($this->body);
+        }
+    }
+
+    public function getPreparedHeaders(): Headers
+    {
+        $headers = parent::getPreparedHeaders();
+
+        $headers->setHeaderBody('Parameterized', 'Content-Type', $this->getMediaType().'/'.$this->getMediaSubtype());
+        if ($this->charset) {
+            $headers->setHeaderParameter('Content-Type', 'charset', $this->charset);
+        }
+        if ($this->name && 'form-data' !== $this->disposition) {
+            $headers->setHeaderParameter('Content-Type', 'name', $this->name);
+        }
+        $headers->setHeaderBody('Text', 'Content-Transfer-Encoding', $this->encoding);
+
+        if (!$headers->has('Content-Disposition') && null !== $this->disposition) {
+            $headers->setHeaderBody('Parameterized', 'Content-Disposition', $this->disposition);
+            if ($this->name) {
+                $headers->setHeaderParameter('Content-Disposition', 'name', $this->name);
+            }
+        }
+
+        return $headers;
+    }
+
+    public function asDebugString(): string
+    {
+        $str = parent::asDebugString();
+        if (null !== $this->charset) {
+            $str .= ' charset: '.$this->charset;
+        }
+        if (null !== $this->disposition) {
+            $str .= ' disposition: '.$this->disposition;
+        }
+
+        return $str;
+    }
+
+    private function getEncoder(): ContentEncoderInterface
+    {
+        if ('8bit' === $this->encoding) {
+            return self::$encoders[$this->encoding] ??= new EightBitContentEncoder();
+        }
+
+        if ('quoted-printable' === $this->encoding) {
+            return self::$encoders[$this->encoding] ??= new QpContentEncoder();
+        }
+
+        return self::$encoders[$this->encoding] ??= new Base64ContentEncoder();
+    }
+
+    private function chooseEncoding(): string
+    {
+        if (null === $this->charset) {
+            return 'base64';
+        }
+
+        return 'quoted-printable';
+    }
+
+    public function __sleep(): array
+    {
+        // convert resources to strings for serialization
+        if (null !== $this->seekable) {
+            $this->body = $this->getBody();
+            $this->seekable = null;
+        }
+
+        $this->_headers = $this->getHeaders();
+
+        return ['_headers', 'body', 'charset', 'subtype', 'disposition', 'name', 'encoding'];
+    }
+
+    /**
+     * @return void
+     */
+    public function __wakeup()
+    {
+        $r = new \ReflectionProperty(AbstractPart::class, 'headers');
+        $r->setValue($this, $this->_headers);
+        unset($this->_headers);
+    }
+}

lib/symfony/mime/README.md

@@ -0,0 +1,13 @@
+MIME Component
+==============
+
+The MIME component allows manipulating MIME messages.
+
+Resources
+---------
+
+ * [Documentation](https://symfony.com/doc/current/components/mime.html)
+ * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+ * [Report issues](https://github.com/symfony/symfony/issues) and
+   [send Pull Requests](https://github.com/symfony/symfony/pulls)
+   in the [main Symfony repository](https://github.com/symfony/symfony)

lib/symfony/mime/RawMessage.php

@@ -0,0 +1,115 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mime;
+
+use Symfony\Component\Mime\Exception\LogicException;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class RawMessage
+{
+    /** @var iterable<string>|string|resource */
+    private $message;
+    private bool $isGeneratorClosed;
+
+    /**
+     * @param iterable<string>|string|resource $message
+     */
+    public function __construct(mixed $message)
+    {
+        $this->message = $message;
+    }
+
+    public function __destruct()
+    {
+        if (\is_resource($this->message)) {
+            fclose($this->message);
+        }
+    }
+
+    public function toString(): string
+    {
+        if (\is_string($this->message)) {
+            return $this->message;
+        }
+
+        if (\is_resource($this->message)) {
+            return stream_get_contents($this->message, -1, 0);
+        }
+
+        $message = '';
+        foreach ($this->message as $chunk) {
+            $message .= $chunk;
+        }
+
+        return $this->message = $message;
+    }
+
+    public function toIterable(): iterable
+    {
+        if ($this->isGeneratorClosed ?? false) {
+            trigger_deprecation('symfony/mime', '6.4', 'Sending an email with a closed generator is deprecated and will throw in 7.0.');
+            // throw new LogicException('Unable to send the email as its generator is already closed.');
+        }
+
+        if (\is_string($this->message)) {
+            yield $this->message;
+
+            return;
+        }
+
+        if (\is_resource($this->message)) {
+            rewind($this->message);
+            while ($line = fgets($this->message)) {
+                yield $line;
+            }
+
+            return;
+        }
+
+        if ($this->message instanceof \Generator) {
+            $message = fopen('php://temp', 'w+');
+            foreach ($this->message as $chunk) {
+                fwrite($message, $chunk);
+                yield $chunk;
+            }
+            $this->isGeneratorClosed = !$this->message->valid();
+            $this->message = $message;
+
+            return;
+        }
+
+        foreach ($this->message as $chunk) {
+            yield $chunk;
+        }
+    }
+
+    /**
+     * @return void
+     *
+     * @throws LogicException if the message is not valid
+     */
+    public function ensureValidity()
+    {
+    }
+
+    public function __serialize(): array
+    {
+        return [$this->toString()];
+    }
+
+    public function __unserialize(array $data): void
+    {
+        [$this->message] = $data;
+    }
+}

lib/symfony/mime/Resources/bin/update_mime_types.php

@@ -0,0 +1,168 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+if ('cli' !== \PHP_SAPI) {
+    throw new Exception('This script must be run from the command line.');
+}
+
+// load new map
+$data = json_decode(file_get_contents('https://cdn.jsdelivr.net/gh/jshttp/mime-db/db.json'), true);
+$new = [];
+foreach ($data as $mimeType => $mimeTypeInformation) {
+    if (!array_key_exists('extensions', $mimeTypeInformation)) {
+        continue;
+    }
+    $new[$mimeType] = $mimeTypeInformation['extensions'];
+}
+
+$xml = simplexml_load_string(file_get_contents('https://gitlab.freedesktop.org/xdg/shared-mime-info/-/raw/master/data/freedesktop.org.xml.in'));
+foreach ($xml as $node) {
+    $exts = [];
+    foreach ($node->glob as $glob) {
+        $pattern = (string) $glob['pattern'];
+        if ('*' != $pattern[0] || '.' != $pattern[1]) {
+            continue;
+        }
+
+        $exts[] = substr($pattern, 2);
+    }
+
+    if (!$exts) {
+        continue;
+    }
+
+    $mt = strtolower((string) $node['type']);
+    $new[$mt] = array_merge($new[$mt] ?? [], $exts);
+    foreach ($node->alias as $alias) {
+        $mt = strtolower((string) $alias['type']);
+        $new[$mt] = array_merge($new[$mt] ?? [], $exts);
+    }
+}
+
+// load current map
+$data = file_get_contents($output = __DIR__.'/../../MimeTypes.php');
+$current = [];
+$pre = '';
+$post = '';
+foreach (explode("\n", $data) as $line) {
+    if (!preg_match("{^        '([^']+/[^']+)' => \['(.+)'\],$}", $line, $matches)) {
+        if (!$current) {
+            $pre .= $line."\n";
+        } else {
+            $post .= $line."\n";
+        }
+        continue;
+    }
+    $current[$matches[1]] = explode("', '", $matches[2]);
+}
+
+$data = $pre;
+
+// reverse map
+// we prefill the extensions with some preferences for content-types
+$exts = [
+    'asice' => ['application/vnd.etsi.asic-e+zip'],
+    'bz2' => ['application/x-bz2'],
+    'csv' => ['text/csv'],
+    'ecma' => ['application/ecmascript'],
+    'flv' => ['video/x-flv'],
+    'gif' => ['image/gif'],
+    'gz' => ['application/x-gzip'],
+    'htm' => ['text/html'],
+    'html' => ['text/html'],
+    'jar' => ['application/x-java-archive'],
+    'jpg' => ['image/jpeg'],
+    'js' => ['text/javascript'],
+    'keynote' => ['application/vnd.apple.keynote'],
+    'key' => ['application/vnd.apple.keynote'],
+    'm3u' => ['audio/x-mpegurl'],
+    'm4a' => ['audio/mp4'],
+    'md' => ['text/markdown', 'text/x-markdown'],
+    'mdb' => ['application/x-msaccess'],
+    'mid' => ['audio/midi'],
+    'mov' => ['video/quicktime'],
+    'mp3' => ['audio/mpeg'],
+    'ogg' => ['audio/ogg'],
+    'pdf' => ['application/pdf'],
+    'php' => ['application/x-php'],
+    'png' => ['image/png'],
+    'ppt' => ['application/vnd.ms-powerpoint'],
+    'rar' => ['application/x-rar-compressed'],
+    'hqx' => ['application/stuffit'],
+    'sit' => ['application/x-stuffit', 'application/stuffit'],
+    'svg' => ['image/svg+xml'],
+    'tar' => ['application/x-tar'],
+    'tif' => ['image/tiff'],
+    'ttf' => ['application/x-font-truetype'],
+    'vcf' => ['text/x-vcard'],
+    'wav' => ['audio/wav'],
+    'wma' => ['audio/x-ms-wma'],
+    'wmv' => ['audio/x-ms-wmv'],
+    'xls' => ['application/vnd.ms-excel'],
+    'yaml' => ['application/yaml'],
+    'yml' => ['application/yaml'],
+    'zip' => ['application/zip'],
+];
+
+// we merge the 2 maps (we never remove old mime types)
+$map = array_replace_recursive($current, $new);
+
+foreach ($exts as $ext => $types) {
+    foreach ($types as $mt) {
+        if (!isset($map[$mt])) {
+            $map += [$mt => [$ext]];
+        }
+    }
+}
+ksort($map);
+
+foreach ($map as $mimeType => $extensions) {
+    foreach ($exts as $ext => $types) {
+        if (in_array($mimeType, $types, true)) {
+            array_unshift($extensions, $ext);
+        }
+    }
+    $data .= sprintf("        '%s' => ['%s'],\n", $mimeType, implode("', '", array_unique($extensions)));
+}
+$data .= $post;
+
+foreach ($map as $mimeType => $extensions) {
+    foreach ($extensions as $extension) {
+        if ('application/octet-stream' === $mimeType && 'bin' !== $extension) {
+            continue;
+        }
+
+        $exts[$extension][] = $mimeType;
+    }
+}
+ksort($exts);
+
+$updated = '';
+$state = 0;
+foreach (explode("\n", $data) as $line) {
+    if (!preg_match("{^        '([^'/]+)' => \['(.+)'\],$}", $line, $matches)) {
+        if (1 === $state) {
+            $state = 2;
+            foreach ($exts as $ext => $mimeTypes) {
+                $updated .= sprintf("        '%s' => ['%s'],\n", $ext, implode("', '", array_unique($mimeTypes)));
+            }
+        }
+        $updated .= $line."\n";
+        continue;
+    }
+    $state = 1;
+}
+
+$updated = preg_replace('{Updated from upstream on .+?\.}', sprintf('Updated from upstream on %s.', date('Y-m-d')), $updated, -1);
+
+file_put_contents($output, rtrim($updated, "\n")."\n");
+
+echo "Done.\n";

lib/symfony/mime/composer.json

@@ -0,0 +1,48 @@
+{
+    "name": "symfony/mime",
+    "type": "library",
+    "description": "Allows manipulating MIME messages",
+    "keywords": ["mime", "mime-type"],
+    "homepage": "https://symfony.com",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Fabien Potencier",
+            "email": "fabien@symfony.com"
+        },
+        {
+            "name": "Symfony Community",
+            "homepage": "https://symfony.com/contributors"
+        }
+    ],
+    "require": {
+        "php": ">=8.1",
+        "symfony/deprecation-contracts": "^2.5|^3",
+        "symfony/polyfill-intl-idn": "^1.10",
+        "symfony/polyfill-mbstring": "^1.0"
+    },
+    "require-dev": {
+        "egulias/email-validator": "^2.1.10|^3.1|^4",
+        "league/html-to-markdown": "^5.0",
+        "phpdocumentor/reflection-docblock": "^3.0|^4.0|^5.0",
+        "symfony/dependency-injection": "^5.4|^6.0|^7.0",
+        "symfony/process": "^5.4|^6.4|^7.0",
+        "symfony/property-access": "^5.4|^6.0|^7.0",
+        "symfony/property-info": "^5.4|^6.0|^7.0",
+        "symfony/serializer": "^6.4.3|^7.0.3"
+    },
+    "conflict": {
+        "egulias/email-validator": "~3.0.0",
+        "phpdocumentor/reflection-docblock": "<3.2.2",
+        "phpdocumentor/type-resolver": "<1.4.0",
+        "symfony/mailer": "<5.4",
+        "symfony/serializer": "<6.4.3|>7.0,<7.0.3"
+    },
+    "autoload": {
+        "psr-4": { "Symfony\\Component\\Mime\\": "" },
+        "exclude-from-classmap": [
+            "/Tests/"
+        ]
+    },
+    "minimum-stability": "dev"
+}