Clean up app_mysql's application entry points to properly parse arguments

When parsing arguments, application entry points should not attempt to
directly modify the parameters to the function. This patch properly duplicates
the passed in parameters before attempting to parse them.

(issue ASTERISK-20658)
Reported by: wdoekes
patches:
  issueA20658_sanitize_app_mysql.patch uploaded by wdoekes (license 5674)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@378384 65c4cc65-6c06-0410-ace0-fbb531ad65f3

addons/app_mysql.c

@@ -292,16 +292,17 @@ static int safe_scan_int(char **data, char *delim, int def)
 	return res;
 }
 
-static int aMYSQL_set(struct ast_channel *chan, char *data)
+static int aMYSQL_set(struct ast_channel *chan, const char *data)
 {
-	char *var, *tmp;
+	char *var, *tmp, *parse;
 	AST_DECLARE_APP_ARGS(args,
 		AST_APP_ARG(set);
 		AST_APP_ARG(variable);
 		AST_APP_ARG(value);
 	);
 
-	AST_NONSTANDARD_APP_ARGS(args, data, ' ');
+	parse = ast_strdupa(data);
+	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
 
 	if (args.argc == 3) {
 		var = ast_alloca(6 + strlen(args.variable) + 1);
@@ -317,7 +318,7 @@ static int aMYSQL_set(struct ast_channel *chan, char *data)
 }
 
 /* MYSQL operations */
-static int aMYSQL_connect(struct ast_channel *chan, char *data)
+static int aMYSQL_connect(struct ast_channel *chan, const char *data)
 {
 	AST_DECLARE_APP_ARGS(args,
 		AST_APP_ARG(connect);
@@ -333,8 +334,9 @@ static int aMYSQL_connect(struct ast_channel *chan, char *data)
 	const char *ctimeout;
 	unsigned int port = 0;
 	char *port_str;
-
-	AST_NONSTANDARD_APP_ARGS(args, data, ' ');
+	char *parse = ast_strdupa(data);
+ 
+	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
 
 	if (args.argc < 6) {
 		ast_log(LOG_WARNING, "MYSQL_connect is missing some arguments\n");
@@ -385,7 +387,7 @@ static int aMYSQL_connect(struct ast_channel *chan, char *data)
 	return 0;
 }
 
-static int aMYSQL_query(struct ast_channel *chan, char *data)
+static int aMYSQL_query(struct ast_channel *chan, const char *data)
 {
 	AST_DECLARE_APP_ARGS(args,
 		AST_APP_ARG(query);
@@ -397,8 +399,9 @@ static int aMYSQL_query(struct ast_channel *chan, char *data)
 	MYSQL_RES   *mysqlres;
 	int connid;
 	int mysql_query_res;
+	char *parse = ast_strdupa(data);
 
-	AST_NONSTANDARD_APP_ARGS(args, data, ' ');
+	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
 
 	if (args.argc != 4 || (connid = atoi(args.connid)) == 0) {
 		ast_log(LOG_WARNING, "missing some arguments\n");
@@ -426,7 +429,7 @@ static int aMYSQL_query(struct ast_channel *chan, char *data)
 	return -1;
 }
 
-static int aMYSQL_nextresult(struct ast_channel *chan, char *data)
+static int aMYSQL_nextresult(struct ast_channel *chan, const char *data)
 {
 	MYSQL       *mysql;
 	MYSQL_RES   *mysqlres;
@@ -436,8 +439,9 @@ static int aMYSQL_nextresult(struct ast_channel *chan, char *data)
 		AST_APP_ARG(connid);
 	);
 	int connid = -1;
+	char *parse = ast_strdupa(data);
 
-	AST_NONSTANDARD_APP_ARGS(args, data, ' ');
+	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
 	sscanf(args.connid, "%30d", &connid);
 
 	if (args.argc != 3 || connid <= 0) {
@@ -466,7 +470,7 @@ static int aMYSQL_nextresult(struct ast_channel *chan, char *data)
 }
 
 
-static int aMYSQL_fetch(struct ast_channel *chan, char *data)
+static int aMYSQL_fetch(struct ast_channel *chan, const char *data)
 {
 	MYSQL_RES *mysqlres;
 	MYSQL_ROW mysqlrow;
@@ -518,13 +522,14 @@ static int aMYSQL_fetch(struct ast_channel *chan, char *data)
 	return -1;
 }
 
-static int aMYSQL_clear(struct ast_channel *chan, char *data)
+static int aMYSQL_clear(struct ast_channel *chan, const char *data)
 {
 	MYSQL_RES *mysqlres;
 
 	int id;
-	strsep(&data, " "); /* eat the first token, we already know it :P */
-	id = safe_scan_int(&data, " \n", -1);
+	char *parse = ast_strdupa(data);
+	strsep(&parse, " "); /* eat the first token, we already know it :P */
+	id = safe_scan_int(&parse, " \n", -1);
 	if ((mysqlres = find_identifier(id, AST_MYSQL_ID_RESID)) == NULL) {
 		ast_log(LOG_WARNING, "Invalid result identifier %d passed in aMYSQL_clear\n", id);
 	} else {
@@ -535,13 +540,14 @@ static int aMYSQL_clear(struct ast_channel *chan, char *data)
 	return 0;
 }
 
-static int aMYSQL_disconnect(struct ast_channel *chan, char *data)
+static int aMYSQL_disconnect(struct ast_channel *chan, const char *data)
 {
 	MYSQL *mysql;
 	int id;
-	strsep(&data, " "); /* eat the first token, we already know it :P */
+	char *parse = ast_strdupa(data);
+	strsep(&parse, " "); /* eat the first token, we already know it :P */
 
-	id = safe_scan_int(&data, " \n", -1);
+	id = safe_scan_int(&parse, " \n", -1);
 	if ((mysql = find_identifier(id, AST_MYSQL_ID_CONNID)) == NULL) {
 		ast_log(LOG_WARNING, "Invalid connection identifier %d passed in aMYSQL_disconnect\n", id);
 	} else {
@@ -584,19 +590,19 @@ static int MYSQL_exec(struct ast_channel *chan, const char *data)
 	ast_mutex_lock(&_mysql_mutex);
 
 	if (strncasecmp("connect", data, strlen("connect")) == 0) {
-		result = aMYSQL_connect(chan, ast_strdupa(data));
+		result = aMYSQL_connect(chan, data);
 	} else if (strncasecmp("query", data, strlen("query")) == 0) {
-		result = aMYSQL_query(chan, ast_strdupa(data));
+		result = aMYSQL_query(chan, data);
 	} else if (strncasecmp("nextresult", data, strlen("nextresult")) == 0) {
-		result = aMYSQL_nextresult(chan, ast_strdupa(data));
+		result = aMYSQL_nextresult(chan, data);
 	} else if (strncasecmp("fetch", data, strlen("fetch")) == 0) {
-		result = aMYSQL_fetch(chan, ast_strdupa(data));
+		result = aMYSQL_fetch(chan, data);
 	} else if (strncasecmp("clear", data, strlen("clear")) == 0) {
-		result = aMYSQL_clear(chan, ast_strdupa(data));
+		result = aMYSQL_clear(chan, data);
 	} else if (strncasecmp("disconnect", data, strlen("disconnect")) == 0) {
-		result = aMYSQL_disconnect(chan, ast_strdupa(data));
+		result = aMYSQL_disconnect(chan, data);
 	} else if (strncasecmp("set", data, 3) == 0) {
-		result = aMYSQL_set(chan, ast_strdupa(data));
+		result = aMYSQL_set(chan, data);
 	} else {
 		ast_log(LOG_WARNING, "Unknown argument to MYSQL application : %s\n", data);
 		result = -1;