Fix GH-19188: Add support for new INI mail.cr_lf_mode (#19238)

NEWS

@@ -57,6 +57,8 @@ PHP                                                                        NEWS
     (Girgias)
   . Fixed bug GH-19577 (Avoid integer overflow when using a small offset
     and PHP_INT_MAX with LimitIterator). (alexandre-daubois)
+  . Implement GH-19188: Add support for new INI mail.cr_lf_mode.
+    (alexandre-daubois)
 
 - Streams:
   . Fixed bug GH-14506 (Closing a userspace stream inside a userspace handler

ext/standard/mail.c

@@ -494,7 +494,27 @@ PHPAPI bool php_mail(const char *to, const char *subject, const char *message, c
 		MAIL_RET(false);
 	}
 
-	char *line_sep = PG(mail_mixed_lf_and_crlf) ? "\n" : "\r\n";
+	char *line_sep;
+	const char *cr_lf_mode = PG(mail_cr_lf_mode);
+	
+	if (cr_lf_mode && strcmp(cr_lf_mode, "crlf") != 0) {
+		if (strcmp(cr_lf_mode, "lf") == 0) {
+			line_sep = "\n";
+		} else if (strcmp(cr_lf_mode, "mixed") == 0) {
+			line_sep = "\n";
+		} else if (strcmp(cr_lf_mode, "os") == 0) {
+#ifdef PHP_WIN32
+			line_sep = "\r\n";
+#else
+			line_sep = "\n";
+#endif
+		} else {
+			ZEND_ASSERT(0 && "Unexpected cr_lf_mode value");
+		}
+	} else {
+		/* CRLF is default mode, but respect mail.mixed_lf_and_crlf for backward compatibility */
+		line_sep = PG(mail_mixed_lf_and_crlf) ? "\n" : "\r\n";
+	}
 
 	if (PG(mail_x_header)) {
 		const char *tmp = zend_get_executed_filename();
@@ -586,7 +606,43 @@ PHPAPI bool php_mail(const char *to, const char *subject, const char *message, c
 		if (hdr != NULL) {
 			fprintf(sendmail, "%s%s", hdr, line_sep);
 		}
-		fprintf(sendmail, "%s%s%s", line_sep, message, line_sep);
+
+		fprintf(sendmail, "%s", line_sep);
+		
+		if (cr_lf_mode && strcmp(cr_lf_mode, "lf") == 0) {
+			char *converted_message = NULL;
+			size_t msg_len = strlen(message);
+			size_t new_len = 0;
+
+			for (size_t i = 0; i < msg_len - 1; ++i) {
+				if (message[i] == '\r' && message[i + 1] == '\n') {
+					++new_len;
+				}
+			}
+
+			if (new_len == 0) {
+				fprintf(sendmail, "%s", message);
+			} else {
+				converted_message = emalloc(msg_len - new_len + 1);
+				size_t j = 0;
+				for (size_t i = 0; i < msg_len; ++i) {
+					if (i < msg_len - 1 && message[i] == '\r' && message[i + 1] == '\n') {
+						converted_message[j++] = '\n';
+						++i; /* skip LF part */
+					} else {
+						converted_message[j++] = message[i];
+					}
+				}
+
+				converted_message[j] = '\0';
+				fprintf(sendmail, "%s", converted_message);
+				efree(converted_message);
+			}
+		} else {
+			fprintf(sendmail, "%s", message);
+		}
+		
+		fprintf(sendmail, "%s", line_sep);
 #ifdef PHP_WIN32
 		ret = pclose(sendmail);
 

ext/standard/tests/mail/gh19188_cr_lf_mode.phpt

@@ -0,0 +1,23 @@
+--TEST--
+GH-19188: new INI mail.cr_lf_mode
+--INI--
+sendmail_path={MAIL:gh19188_cr_lf_mode.out}
+mail.cr_lf_mode=crlf
+--FILE--
+<?php
+
+var_dump(mail('user@example.com', 'Test Subject', 'A Message', 'X-Test: crlf'));
+$mail = file_get_contents('gh19188_cr_lf_mode.out');
+echo "CRLF mode:\n";
+var_dump(preg_match_all('/\r\n/', $mail));
+var_dump(preg_match_all('/(?<!\r)\n/', $mail));
+?>
+--CLEAN--
+<?php
+@unlink('gh19188_cr_lf_mode.out');
+?>
+--EXPECT--
+bool(true)
+CRLF mode:
+int(5)
+int(0)

ext/standard/tests/mail/gh19188_invalid_mode.phpt

@@ -0,0 +1,26 @@
+--TEST--
+GH-19188: mail.cr_lf_mode runtime changes should fail
+--FILE--
+<?php
+
+var_dump(ini_set('mail.cr_lf_mode', 'lf'));
+var_dump(ini_get('mail.cr_lf_mode'));
+
+var_dump(ini_set('mail.cr_lf_mode', 'mixed'));
+var_dump(ini_get('mail.cr_lf_mode'));
+
+var_dump(ini_set('mail.cr_lf_mode', 'os'));
+var_dump(ini_get('mail.cr_lf_mode'));
+
+var_dump(ini_set('mail.cr_lf_mode', 'invalid'));
+var_dump(ini_get('mail.cr_lf_mode'));
+?>
+--EXPECT--
+bool(false)
+string(4) "crlf"
+bool(false)
+string(4) "crlf"
+bool(false)
+string(4) "crlf"
+bool(false)
+string(4) "crlf"

ext/standard/tests/mail/gh19188_lf_mode.phpt

@@ -0,0 +1,23 @@
+--TEST--
+GH-19188: mail.cr_lf_mode=lf
+--INI--
+sendmail_path={MAIL:gh19188_lf_mode.out}
+mail.cr_lf_mode=lf
+--FILE--
+<?php
+
+var_dump(mail('user@example.com', 'Test Subject', "A Message\r\nWith CRLF", 'X-Test: lf'));
+$mail = file_get_contents('gh19188_lf_mode.out');
+echo "LF mode:\n";
+var_dump(preg_match_all('/\r\n/', $mail));
+var_dump(preg_match_all('/(?<!\r)\n/', $mail));
+?>
+--CLEAN--
+<?php
+@unlink('gh19188_lf_mode.out');
+?>
+--EXPECT--
+bool(true)
+LF mode:
+int(0)
+int(6)

ext/standard/tests/mail/gh19188_mixed_mode.phpt

@@ -0,0 +1,20 @@
+--TEST--
+GH-19188: mail.cr_lf_mode=mixed
+--INI--
+sendmail_path={MAIL:gh19188_mixed_mode.out}
+mail.cr_lf_mode=mixed
+--FILE--
+<?php
+var_dump(mail('user@example.com', 'Test Subject', 'A Message', 'X-Test: mixed'));
+$mail = file_get_contents('gh19188_mixed_mode.out');
+echo "Mixed mode:\n";
+var_dump(preg_match_all('/(?<!\r)\n/', $mail));
+?>
+--CLEAN--
+<?php
+@unlink('gh19188_mixed_mode.out');
+?>
+--EXPECT--
+bool(true)
+Mixed mode:
+int(5)

ext/standard/tests/mail/gh19188_os_mode_unix.phpt

@@ -0,0 +1,30 @@
+--TEST--
+GH-19188: mail.cr_lf_mode=os (Unix)
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') die("skip Non-Windows only");
+?>
+--INI--
+sendmail_path={MAIL:gh19188_os_mode.out}
+mail.cr_lf_mode=os
+--FILE--
+<?php
+var_dump(mail('user@example.com', 'Test Subject', 'A Message', 'X-Test: os'));
+$mail = file_get_contents('gh19188_os_mode.out');
+echo "OS mode:\n";
+$crlf_count = preg_match_all('/\r\n/', $mail);
+$lf_only_count = preg_match_all('/(?<!\r)\n/', $mail);
+echo "CRLF count: ";
+var_dump($crlf_count);
+echo "LF-only count: ";
+var_dump($lf_only_count);
+?>
+--CLEAN--
+<?php
+@unlink('gh19188_os_mode.out');
+?>
+--EXPECT--
+bool(true)
+OS mode:
+CRLF count: int(0)
+LF-only count: int(5)

ext/standard/tests/mail/gh19188_os_mode_windows.phpt

@@ -0,0 +1,31 @@
+--TEST--
+GH-19188: mail.cr_lf_mode=os (Windows)
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY !== 'Windows') die("skip Windows only");
+?>
+--INI--
+sendmail_path={MAIL:gh19188_os_mode.out}
+mail.cr_lf_mode=os
+--FILE--
+<?php
+
+var_dump(mail('user@example.com', 'Test Subject', 'A Message', 'X-Test: os'));
+$mail = file_get_contents('gh19188_os_mode.out');
+echo "OS mode:\n";
+$crlf_count = preg_match_all('/\r\n/', $mail);
+$lf_only_count = preg_match_all('/(?<!\r)\n/', $mail);
+echo "CRLF count: ";
+var_dump($crlf_count);
+echo "LF-only count: ";
+var_dump($lf_only_count);
+?>
+--CLEAN--
+<?php
+@unlink('gh19188_os_mode.out');
+?>
+--EXPECT--
+bool(true)
+OS mode:
+CRLF count: int(5)
+LF-only count: int(0)

main/main.c

@@ -721,6 +721,36 @@ static PHP_INI_MH(OnUpdateMailLog)
 }
 /* }}} */
 
+/* {{{ PHP_INI_MH */
+static PHP_INI_MH(OnUpdateMailCrLfMode)
+{
+	if (new_value) {
+		const char *val = ZSTR_VAL(new_value);
+		if (ZSTR_LEN(new_value) > 0 &&
+			strcmp(val, "crlf") != 0 &&
+			strcmp(val, "lf") != 0 &&
+			strcmp(val, "mixed") != 0 &&
+			strcmp(val, "os") != 0) {
+			int err_type;
+
+			if (stage == ZEND_INI_STAGE_RUNTIME) {
+				err_type = E_WARNING;
+			} else {
+				err_type = E_ERROR;
+			}
+
+			if (stage != ZEND_INI_STAGE_DEACTIVATE) {
+				php_error_docref(NULL, err_type, "Invalid value \"%s\" for mail.cr_lf_mode. Must be one of: \"crlf\", \"lf\", \"mixed\", \"os\"", val);
+			}
+
+			return FAILURE;
+		}
+	}
+	OnUpdateString(entry, new_value, mh_arg1, mh_arg2, mh_arg3, stage);
+	return SUCCESS;
+}
+/* }}} */
+
 /* {{{ PHP_INI_MH */
 static PHP_INI_MH(OnChangeMailForceExtra)
 {
@@ -826,6 +856,7 @@ PHP_INI_BEGIN()
 	PHP_INI_ENTRY("smtp_port",					"25",		PHP_INI_ALL,		NULL)
 	STD_PHP_INI_BOOLEAN("mail.add_x_header",			"0",		PHP_INI_SYSTEM|PHP_INI_PERDIR,		OnUpdateBool,			mail_x_header,			php_core_globals,	core_globals)
 	STD_PHP_INI_BOOLEAN("mail.mixed_lf_and_crlf",			"0",		PHP_INI_SYSTEM|PHP_INI_PERDIR,		OnUpdateBool,			mail_mixed_lf_and_crlf,			php_core_globals,	core_globals)
+	STD_PHP_INI_ENTRY("mail.cr_lf_mode",				"crlf",		PHP_INI_SYSTEM|PHP_INI_PERDIR,		OnUpdateMailCrLfMode,		mail_cr_lf_mode,		php_core_globals,	core_globals)
 	STD_PHP_INI_ENTRY("mail.log",					NULL,		PHP_INI_SYSTEM|PHP_INI_PERDIR,		OnUpdateMailLog,			mail_log,			php_core_globals,	core_globals)
 	PHP_INI_ENTRY("browscap",					NULL,		PHP_INI_SYSTEM,		OnChangeBrowscap)
 

main/php_globals.h

@@ -154,6 +154,7 @@ struct _php_core_globals {
 	char *mail_log;
 	bool mail_x_header;
 	bool mail_mixed_lf_and_crlf;
+	char *mail_cr_lf_mode;
 
 	bool in_error_log;
 

php.ini-development

@@ -1086,6 +1086,14 @@ mail.add_x_header = Off
 ; RFC 2822 non conformant MTA.
 mail.mixed_lf_and_crlf = Off
 
+; Control line ending mode for mail messages and headers.
+; Possible values: "crlf" (default), "lf", "mixed", "os"
+; - crlf: Use CRLF line endings
+; - lf: Use LF line endings only (converts CRLF in message to LF)
+; - mixed: Same as mail.mixed_lf_and_crlf = On
+; - os: Use CRLF on Windows, LF on other systems
+mail.cr_lf_mode = crlf
+
 ; The path to a log file that will log all mail() calls. Log entries include
 ; the full path of the script, line number, To address and headers.
 ;mail.log =

php.ini-production

@@ -1088,6 +1088,14 @@ mail.add_x_header = Off
 ; RFC 2822 non conformant MTA.
 mail.mixed_lf_and_crlf = Off
 
+; Control line ending mode for mail messages and headers.
+; Possible values: "crlf" (default), "lf", "mixed", "os"
+; - crlf: Use CRLF line endings
+; - lf: Use LF line endings only (converts CRLF in message to LF)
+; - mixed: Same as mail.mixed_lf_and_crlf = On
+; - os: Use CRLF on Windows, LF on other systems
+mail.cr_lf_mode = crlf
+
 ; The path to a log file that will log all mail() calls. Log entries include
 ; the full path of the script, line number, To address and headers.
 ;mail.log =