From 874817b169d19a4ae51d80ad5798a396bfe90136 Mon Sep 17 00:00:00 2001

From: Stephan Bosch <stephan.bosch@open-xchange.com>

Date: Tue, 24 Mar 2020 21:14:34 +0100

Subject: [PATCH] lib-smtp: smtp-syntax - Do not allow NULL return parameters

 for smtp_ehlo_line_parse().

---

 src/lib-smtp/smtp-syntax.c | 39 +++++++++++++++++---------------------

 1 file changed, 17 insertions(+), 22 deletions(-)

diff --git a/src/lib-smtp/smtp-syntax.c b/src/lib-smtp/smtp-syntax.c

index 0b0a91ce07..5cca6c40fd 100644

--- a/src/lib-smtp/smtp-syntax.c

+++ b/src/lib-smtp/smtp-syntax.c

@@ -249,12 +249,10 @@ static int smtp_parse_ehlo_line(struct smtp_parser *parser,

 		(i_isalnum(*parser->cur) || *parser->cur == '-'))

 		parser->cur++;

-	if (key_r != NULL)

-		*key_r = p_strdup_until(parser->pool, pbegin, parser->cur);

+	*key_r = p_strdup_until(parser->pool, pbegin, parser->cur);

 	if (parser->cur >= parser->end) {

-		if (params_r != NULL)

-			*params_r = p_new(parser->pool, const char *, 1);

+		*params_r = p_new(parser->pool, const char *, 1);

 		return 1;

 	}

 	if (*parser->cur != ' ') {

@@ -264,18 +262,16 @@ static int smtp_parse_ehlo_line(struct smtp_parser *parser,

 	parser->cur++;

 	pbegin = parser->cur;

-	if (params_r != NULL)

-		p_array_init(&params, parser->pool, 32);

+	p_array_init(&params, parser->pool, 32);

 	while (parser->cur < parser->end) {

 		if (*parser->cur == ' ') {

 			if (parser->cur+1 >= parser->end || *(parser->cur+1) == ' ') {

 				parser->error = "Missing EHLO parameter after ' '";

 				return -1;

 			}

-			if (params_r != NULL) {

-				param = p_strdup_until(parser->pool, pbegin, parser->cur);

-				array_push_back(&params, ¶m;;

-			}

+			param = p_strdup_until(parser->pool, pbegin,

+					       parser->cur);

+			array_push_back(&params, ¶m;;

 			pbegin = parser->cur + 1;

 		} else if (!smtp_char_is_ehlo_param(*parser->cur)) {

 			parser->error = "Unexpected character in EHLO parameter";

@@ -284,12 +280,10 @@ static int smtp_parse_ehlo_line(struct smtp_parser *parser,

 		parser->cur++;

 	}

-	if (params_r != NULL) {

-		param = p_strdup_until(parser->pool, pbegin, parser->cur);

-		array_push_back(&params, ¶m;;

-		array_append_zero(&params);

-		*params_r = array_front(&params);

-	}

+	param = p_strdup_until(parser->pool, pbegin, parser->cur);

+	array_push_back(&params, ¶m;;

+	array_append_zero(&params);

+	*params_r = array_front(&params);

 	return 1;

 }

@@ -297,19 +291,20 @@ int smtp_ehlo_line_parse(const char *ehlo_line, const char **key_r,

 	const char *const **params_r, const char **error_r)

 {

 	struct smtp_parser parser;

-	int ret;

+

+	*key_r = NULL;

+	*params_r = NULL;

+	*error_r = NULL;

 	if (ehlo_line == NULL || *ehlo_line == '\0') {

-		if (error_r != NULL)

-			*error_r = "Parameter is empty";

+		*error_r = "Parameter is empty";

 		return -1;

 	}

 	smtp_parser_init(&parser, pool_datastack_create(), ehlo_line);

-	if ((ret=smtp_parse_ehlo_line(&parser, key_r, params_r)) <= 0) {

-		if (error_r != NULL)

-			*error_r = parser.error;

+	if (smtp_parse_ehlo_line(&parser, key_r, params_r) <= 0) {

+		*error_r = parser.error;

 		return -1;

 	}

 	return 1;