Describe this repository

encodeHeader() fell back to us-ascii for any header value without 8-bit
chars, which mislabelled ISO-2022-JP text. Values containing ESC escape
sequences now keep the message charset.

Fixes #2185

README.md

@@ -0,0 +1,12 @@
+# Contributions to PHPMailer/PHPMailer
+
+The classic email sending library for PHP
+
+This repository holds only my commits to the upstream project, with their original author, date and diff.
+Each of my commits is preceded by a snapshot of the upstream files it touched, so every diff shows exactly what I changed.
+
+## Merged pull requests
+
+- [Don't send QUIT while DATA is in progress](https://github.com/PHPMailer/PHPMailer/pull/3362) (2026-10-04)
+- [Fold long address headers](https://github.com/PHPMailer/PHPMailer/pull/3361) (2026-10-04)
+- [Normalise line breaks in S/MIME signed messages](https://github.com/PHPMailer/PHPMailer/pull/3358) (2026-09-10)

src/PHPMailer.php

@@ -2647,7 +2647,22 @@ class PHPMailer
             $addresses[] = $this->addrFormat($address);
         }
 
-        return $type . ': ' . implode(', ', $addresses) . static::$LE;
+        //Fold between addresses so that no line exceeds the RFC 2822 line length limit
+        $header = $type . ': ' . array_shift($addresses);
+        $lineLength = strlen($header);
+        foreach ($addresses as $address) {
+            //The address goes after ', ' and must still leave room for the ',' that ends
+            //the line if the next address gets folded
+            if ($lineLength + strlen(', ') + strlen($address) + strlen(',') > static::MAX_LINE_LENGTH) {
+                $header .= ',' . static::$LE . ' ' . $address;
+                $lineLength = strlen(' ') + strlen($address);
+            } else {
+                $header .= ', ' . $address;
+                $lineLength += strlen(', ') + strlen($address);
+            }
+        }
+
+        return $header . static::$LE;
     }
 
     /**
@@ -3320,8 +3335,9 @@ class PHPMailer
                     @unlink($signed);
                     //The message returned by openssl contains both headers and body, so need to split them up
                     $parts = explode("\n\n", $body, 2);
-                    $this->MIMEHeader .= $parts[0] . static::$LE . static::$LE;
-                    $body = $parts[1];
+                    //openssl emits bare LF breaks, which SMTP servers may reject
+                    $this->MIMEHeader .= static::normalizeBreaks($parts[0]) . static::$LE . static::$LE;
+                    $body = static::normalizeBreaks($parts[1]);
                 } else {
                     @unlink($signed);
                     throw new Exception(self::lang('signing') . openssl_error_string());
@@ -3752,7 +3768,8 @@ class PHPMailer
                 break;
         }
 
-        if ($this->has8bitChars($str)) {
+        //ISO-2022 charsets such as ISO-2022-JP are 7-bit, but text using their escape sequences isn't us-ascii
+        if ($this->has8bitChars($str) || strpos($str, "\x1B") !== false) {
             $charset = $this->CharSet;
         } else {
             $charset = static::CHARSET_ASCII;

test/PHPMailer/AddrAppendTest.php

@@ -0,0 +1,64 @@
+<?php
+
+/**
+ * PHPMailer - PHP email transport unit tests.
+ * PHP version 5.5.
+ *
+ * @author    Marcus Bointon <phpmailer@synchromedia.co.uk>
+ * @author    Andy Prevost
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   https://www.gnu.org/licenses/old-licenses/lgpl-2.1.html GNU Lesser General Public License
+ */
+
+namespace PHPMailer\Test\PHPMailer;
+
+use PHPMailer\PHPMailer\PHPMailer;
+use PHPMailer\Test\TestCase;
+
+/**
+ * Test creating address headers.
+ *
+ * @covers \PHPMailer\PHPMailer\PHPMailer::addrAppend
+ */
+final class AddrAppendTest extends TestCase
+{
+    /**
+     * A short address list stays on one line.
+     */
+    public function testShortListIsNotFolded()
+    {
+        $header = $this->Mail->addrAppend('To', [['joe@example.com', 'Joe'], ['zoe@example.com', '']]);
+
+        self::assertSame('To: Joe <joe@example.com>, zoe@example.com' . PHPMailer::CRLF, $header);
+    }
+
+    /**
+     * A long address list is folded between addresses so no line exceeds the RFC 5322 limit.
+     */
+    public function testLongListIsFolded()
+    {
+        $addresses = [];
+        $formatted = [];
+        for ($i = 1; $i <= 100; ++$i) {
+            $addresses[] = ['recipient' . $i . '@example.com', 'Recipient ' . $i];
+            $formatted[] = 'Recipient ' . $i . ' <recipient' . $i . '@example.com>';
+        }
+
+        $header = $this->Mail->addrAppend('Cc', $addresses);
+        $lines = explode(PHPMailer::CRLF, substr($header, 0, -strlen(PHPMailer::CRLF)));
+
+        self::assertGreaterThan(1, count($lines), 'The header was not folded');
+        foreach ($lines as $index => $line) {
+            self::assertLessThanOrEqual(PHPMailer::MAX_LINE_LENGTH, strlen($line), "Line $index is too long");
+            if ($index > 0) {
+                self::assertSame(' ', $line[0], "Line $index is not a folded continuation");
+            }
+        }
+        self::assertSame(
+            'Cc: ' . implode(', ', $formatted) . PHPMailer::CRLF,
+            str_replace(PHPMailer::CRLF . ' ', ' ', $header),
+            'Unfolding the header did not give back the address list'
+        );
+    }
+}

test/PHPMailer/EncodeHeaderTest.php

@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * PHPMailer - PHP email transport unit tests.
+ * PHP version 5.5.
+ *
+ * @author    Marcus Bointon <phpmailer@synchromedia.co.uk>
+ * @author    Andy Prevost
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   https://www.gnu.org/licenses/old-licenses/lgpl-2.1.html GNU Lesser General Public License
+ */
+
+namespace PHPMailer\Test\PHPMailer;
+
+use PHPMailer\Test\TestCase;
+
+/**
+ * Test the charset label chosen when encoding header values.
+ *
+ * @covers \PHPMailer\PHPMailer\PHPMailer::encodeHeader
+ */
+final class EncodeHeaderTest extends TestCase
+{
+    /**
+     * Test the charset label used for 7-bit header values.
+     *
+     * @dataProvider dataEncodeHeaderCharset
+     *
+     * @param string $input    The header value to encode.
+     * @param string $expected The expected function return value.
+     * @param string $charset  The charset to use.
+     */
+    public function testEncodeHeaderCharset($input, $expected, $charset)
+    {
+        $this->Mail->CharSet = $charset;
+
+        self::assertSame($expected, $this->Mail->encodeHeader($input));
+    }
+
+    /**
+     * Data provider.
+     *
+     * @return array
+     */
+    public static function dataEncodeHeaderCharset()
+    {
+        return [
+            'ISO-2022-JP text keeps its charset label even though it is 7-bit' => [
+                //"Test" in Japanese katakana, converted to ISO-2022-JP
+                'input'    => "\x1B\$B%F%9%H\x1B(B",
+                'expected' => '=?ISO-2022-JP?Q?=1B$B%F%9%H=1B(B?=',
+                'charset'  => 'ISO-2022-JP',
+            ],
+            'ISO-2022-JP text in the middle of ASCII text keeps its charset label' => [
+                'input'    => "Re: \x1B\$B%F%9%H\x1B(B",
+                'expected' => '=?ISO-2022-JP?Q?Re:_=1B$B%F%9%H=1B(B?=',
+                'charset'  => 'ISO-2022-JP',
+            ],
+            'Plain ASCII text with an ISO-2022-JP charset is not encoded' => [
+                'input'    => 'Test',
+                'expected' => 'Test',
+                'charset'  => 'ISO-2022-JP',
+            ],
+            'ASCII text with a control character still falls back to us-ascii' => [
+                'input'    => "Joe\x7FBloggs",
+                'expected' => '=?us-ascii?Q?Joe=7FBloggs?=',
+                'charset'  => 'utf-8',
+            ],
+        ];
+    }
+}

test/PHPMailer/MailTransportTest.php

@@ -0,0 +1,298 @@
+<?php
+
+/**
+ * PHPMailer - PHP email transport unit tests.
+ * PHP version 5.5.
+ *
+ * @author    Marcus Bointon <phpmailer@synchromedia.co.uk>
+ * @author    Andy Prevost
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   https://www.gnu.org/licenses/old-licenses/lgpl-2.1.html GNU Lesser General Public License
+ */
+
+namespace PHPMailer\Test\PHPMailer;
+
+use PHPMailer\PHPMailer\PHPMailer;
+use PHPMailer\Test\SendTestCase;
+
+/**
+ * Test sending mail using the various available mail transport options.
+ */
+final class MailTransportTest extends SendTestCase
+{
+    /** @var string */
+    private $originalSendmailFrom = '';
+
+    protected function set_up()
+    {
+        parent::set_up();
+
+        $from = ini_get('sendmail_from');
+        $this->originalSendmailFrom = $from === false ? '' : $from;
+    }
+
+    protected function tear_down()
+    {
+        ini_set('sendmail_from', $this->originalSendmailFrom);
+        parent::tear_down();
+    }
+
+    /**
+     * Test sending using SendMail.
+     *
+     * @covers \PHPMailer\PHPMailer\PHPMailer::isSendmail
+     */
+    public function testSendmailSend()
+    {
+        $this->Mail->Body = 'Sending via sendmail';
+        $this->buildBody();
+        $subject = $this->Mail->Subject;
+
+        $this->Mail->Subject = $subject . ': sendmail';
+        $this->Mail->isSendmail();
+
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+    }
+
+    /**
+     * Test sending using Qmail.
+     *
+     * @covers \PHPMailer\PHPMailer\PHPMailer::isQmail
+     */
+    public function testQmailSend()
+    {
+        // Only run if we have qmail installed.
+        if (file_exists('/var/qmail/bin/qmail-inject') === false) {
+            self::markTestSkipped('Qmail is not installed');
+        }
+
+        $this->Mail->Body = 'Sending via qmail';
+        $this->buildBody();
+        $subject = $this->Mail->Subject;
+
+        $this->Mail->Subject = $subject . ': qmail';
+        $this->Mail->isQmail();
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+    }
+
+    /**
+     * Test sending using PHP mail() function.
+     *
+     * @covers \PHPMailer\PHPMailer\PHPMailer::isMail
+     */
+    public function testMailSend()
+    {
+        $this->Mail->Body = 'Sending via mail()';
+        $this->buildBody();
+        $this->Mail->Subject = $this->Mail->Subject . ': mail()';
+        $this->Mail->clearAddresses();
+        $this->Mail->clearCCs();
+        $this->Mail->clearBCCs();
+        $this->setAddress('testmailsend@example.com', 'totest');
+        $this->setAddress('cctestmailsend@example.com', 'cctest', $sType = 'cc');
+        $this->setAddress('bcctestmailsend@example.com', 'bcctest', $sType = 'bcc');
+
+        self::assertContains('testmailsend@example.com', $this->Mail->getToAddresses()[0], 'To address not found');
+        self::assertContains('cctestmailsend@example.com', $this->Mail->getCcAddresses()[0], 'CC address not found');
+        self::assertContains('bcctestmailsend@example.com', $this->Mail->getBccAddresses()[0], 'BCC address not found');
+
+        self::assertTrue(
+            $this->Mail->getAllRecipientAddresses()['testmailsend@example.com'],
+            'To address not in recipient addresses'
+        );
+        self::assertTrue(
+            $this->Mail->getAllRecipientAddresses()['cctestmailsend@example.com'],
+            'CC address not in recipient addresses'
+        );
+        self::assertTrue(
+            $this->Mail->getAllRecipientAddresses()['bcctestmailsend@example.com'],
+            'BCC address not in recipient addresses'
+        );
+
+        $this->Mail->createHeader();
+        $this->Mail->isMail();
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+
+        $msg = $this->Mail->getSentMIMEMessage();
+        self::assertStringNotContainsString("\r\n\r\nMIME-Version:", $msg, 'Incorrect MIME headers');
+    }
+
+    /**
+     * Test that a long To list is folded before it is passed to mail().
+     *
+     * @covers \PHPMailer\PHPMailer\PHPMailer::mailSend
+     */
+    public function testMailSendFoldsLongToList()
+    {
+        $this->Mail->Body = 'Sending via mail()';
+        $this->buildBody();
+        $this->Mail->Subject = $this->Mail->Subject . ': mail()';
+        $this->Mail->clearAddresses();
+        for ($i = 1; $i <= 100; ++$i) {
+            $this->Mail->addAddress('recipient' . $i . '@example.com', 'Recipient ' . $i);
+        }
+
+        $to = '';
+        $this->Mail->Debugoutput = static function ($str) use (&$to) {
+            if (strpos($str, 'To: ') === 0) {
+                $to = substr($str, 4);
+            }
+        };
+        $this->Mail->isMail();
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+
+        $lines = explode(PHPMailer::getLE(), 'To: ' . $to);
+        self::assertGreaterThan(1, count($lines), 'The To list was not folded');
+        foreach ($lines as $index => $line) {
+            self::assertLessThanOrEqual(PHPMailer::MAX_LINE_LENGTH, strlen($line), "Line $index is too long");
+        }
+        self::assertStringContainsString(
+            'To: ' . $to . PHPMailer::getLE(),
+            $this->Mail->getSentMIMEMessage(),
+            'mail() did not get the same To list as the message header'
+        );
+    }
+
+    /**
+     * Test sending using PHP mail() function with Sender address
+     * and explicit sendmail_from ini set.
+     * Test running required with:
+     * php -d sendmail_path="/usr/sbin/sendmail -t -i -frpath@example.org" ./vendor/bin/phpunit
+     *
+     * @group sendmailparams
+     * @covers \PHPMailer\PHPMailer\PHPMailer::isMail
+     */
+    public function testMailSendWithSendmailParams()
+    {
+        $sender = 'rpath@example.org';
+
+        if (strpos(ini_get('sendmail_path'), $sender) === false) {
+            self::markTestSkipped('Custom Sendmail php.ini not available');
+        }
+
+        $this->Mail->Body = 'Sending via mail()';
+        $this->buildBody();
+        $this->Mail->Subject = $this->Mail->Subject . ': mail()';
+        $this->Mail->clearAddresses();
+        $this->setAddress('testmailsend@example.com', 'totest');
+
+        ini_set('sendmail_from', $sender);
+        $this->Mail->createHeader();
+        $this->Mail->isMail();
+
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+    }
+
+    /**
+     * Test sending using SendMail with Sender address
+     * and explicit sendmail_from ini set.
+     * Test running required with:
+     * php -d sendmail_path="/usr/sbin/sendmail -t -i -frpath@example.org" ./vendor/bin/phpunit
+     *
+     * @group sendmailparams
+     * @covers \PHPMailer\PHPMailer\PHPMailer::isSendmail
+     */
+    public function testSendmailSendWithSendmailParams()
+    {
+        $sender = 'rpath@example.org';
+
+        if (strpos(ini_get('sendmail_path'), $sender) === false) {
+            self::markTestSkipped('Custom Sendmail php.ini not available');
+        }
+
+        $this->Mail->Body = 'Sending via sendmail';
+        $this->buildBody();
+        $subject = $this->Mail->Subject;
+
+        $this->Mail->Subject = $subject . ': sendmail';
+        ini_set('sendmail_from', $sender);
+        $this->Mail->isSendmail();
+
+        self::assertTrue($this->Mail->send(), $this->Mail->ErrorInfo);
+    }
+
+    /**
+     * Test parsing of sendmail path and with certain parameters.
+     *
+     * @group sendmailparams
+     * @covers \PHPMailer\PHPMailer\PHPMailer::parseSendmailPath
+     * @dataProvider sendmailPathProvider
+     *
+     * @param string $sendmailPath The sendmail path to parse.
+     * @param string $expectedCommand The expected command after parsing.
+     * @param string  $expectedSender The expected Sender (-f parameter) after parsing.
+     */
+    public function testParseSendmailPath($sendmailPath, $expectedCommand, $expectedSender)
+    {
+        $mailer = $this->Mail;
+
+        $parseSendmailPath = \Closure::bind(
+            function ($path) {
+                return $this->{'parseSendmailPath'}($path);
+            },
+            $mailer,
+            \PHPMailer\PHPMailer\PHPMailer::class
+        );
+        $command = $parseSendmailPath($sendmailPath);
+
+        self::assertSame($expectedCommand, $command, 'Sendmail command not parsed correctly');
+        self::assertSame($expectedSender, $mailer->Sender, 'Sender property not set correctly');
+    }
+
+    /**
+     * Data provider for testParseSendmailPath.
+     *
+     * @return array{
+     *   0: string, // The sendmail path to parse.
+     *   1: string, // The expected command after parsing.
+     *   2: string  // The expected Sender (-f parameter) after parsing.
+     * }
+     */
+
+    public static function sendmailPathProvider()
+    {
+        return [
+            'path only' => [
+                '/usr/sbin/sendmail',
+                '/usr/sbin/sendmail',
+                ''
+            ],
+            'with i and t' => [
+                '/usr/sbin/sendmail -i -t',
+                '/usr/sbin/sendmail',
+                ''
+            ],
+            'with f concatenated' => [
+                '/usr/sbin/sendmail -frpath@example.org -i',
+                '/usr/sbin/sendmail',
+                'rpath@example.org'
+            ],
+            'with f separated' => [
+                '/usr/sbin/sendmail -f rpath@example.org -t',
+                '/usr/sbin/sendmail',
+                'rpath@example.org',
+            ],
+            'with extra flags preserved' => [
+                '/opt/sendmail -x -y -fuser@example.org',
+                '/opt/sendmail -x -y',
+                'user@example.org',
+            ],
+            "extra flags with values preserved" => [
+                '/opt/sendmail -X /path/to/logfile -fuser@example.org',
+                '/opt/sendmail -X /path/to/logfile',
+                'user@example.org',
+            ],
+            "extra flags concatenated preserved" => [
+                '/opt/sendmail -X/path/to/logfile -t -i',
+                '/opt/sendmail -X/path/to/logfile',
+                '',
+            ],
+            "option values with regular parameters" => [
+                '/opt/sendmail -oi -t',
+                '/opt/sendmail',
+                '',
+            ],
+        ];
+    }
+}

test/PHPMailer/PHPMailerTest.php

@@ -971,6 +971,11 @@ EOT;
 
         $msg = $this->Mail->getSentMIMEMessage();
         self::assertStringNotContainsString("\r\n\r\nMIME-Version:", $msg, 'Incorrect MIME headers');
+        self::assertSame(
+            0,
+            preg_match_all("/(?<!\r)\n/", $msg),
+            'Signed message contains bare line feeds'
+        );
         unlink($certfile);
         unlink($keyfile);
     }
@@ -1111,6 +1116,37 @@ EOT;
         self::assertFalse($smtp->mail("somewhere\nbad"), 'Bad SMTP command containing breaks accepted');
     }
 
+    /**
+     * Closing a connection in the middle of DATA must not send QUIT, as the server would take it as message content.
+     */
+    public function testQuitDuringData()
+    {
+        self::assertTrue($this->Mail->smtpConnect(), 'SMTP connect failed');
+        $smtp = $this->Mail->getSMTPInstance();
+        //Don't wait long for a reply that should never be requested
+        $smtp->Timelimit = 5;
+        self::assertTrue($smtp->mail('phpunit@example.com'));
+        self::assertTrue($smtp->recipient('somebody@example.com'));
+
+        //Start DATA without sending the message, as if the send had been interrupted
+        $reflMethod = new \ReflectionMethod($smtp, 'sendCommand');
+        (\PHP_VERSION_ID < 80100) && $reflMethod->setAccessible(true);
+        self::assertTrue($reflMethod->invoke($smtp, 'DATA', 'DATA', 354));
+        (\PHP_VERSION_ID < 80100) && $reflMethod->setAccessible(false);
+
+        $sent = '';
+        $smtp->setDebugLevel(SMTP::DEBUG_CLIENT);
+        $smtp->setDebugOutput(
+            static function ($str) use (&$sent) {
+                $sent .= $str;
+            }
+        );
+        $smtp->quit();
+
+        self::assertStringNotContainsString('QUIT', $sent, 'QUIT was sent during DATA');
+        self::assertFalse($smtp->connected(), 'Connection was not closed');
+    }
+
     /**
      * Tests setting and retrieving ConfirmReadingTo address, also known as "read receipt" address.
      */