FS-5449: --resolve add a mod_commands function to use the shell escape function and update the existing function to use correct escaping

adds a pool based implementation of the switch_util_quote_shell_arg function and changes existing function to be a wrapper around the pool based one

src/include/switch_utils.h

@@ -910,10 +910,19 @@ SWITCH_DECLARE(int) switch_strcasecmp_any(const char *str, ...);
 /*!
   \brief Quote shell argument
   \param string the string to quote (example: a ' b"' c)
-  \return the quoted string (gives: 'a '\'' b"'\'' c' for unices, "a ' b ' c" for MS Windows)
+  \return the quoted string (gives: 'a '\'' b"'\'' c' for unices, "a ' b ' c" for MS Windows), should be freed
 */
 SWITCH_DECLARE(char *) switch_util_quote_shell_arg(const char *string);
 
+/*!
+  \brief Quote shell argument, allocating from pool if provided
+  \param string the string to quote (example: a ' b"' c)
+  \param pool a memory pool to use
+  \return the quoted string (gives: 'a '\'' b"'\'' c' for unices, "a ' b ' c" for MS Windows), if pool not provided, returned value should be freed
+*/
+SWITCH_DECLARE(char *) switch_util_quote_shell_arg_pool(const char *string, switch_memory_pool_t *pool);
+
+
 #define SWITCH_READ_ACCEPTABLE(status) (status == SWITCH_STATUS_SUCCESS || status == SWITCH_STATUS_BREAK)
 SWITCH_DECLARE(char *) switch_url_encode(const char *url, char *buf, size_t len);
 SWITCH_DECLARE(char *) switch_url_decode(char *s);

src/mod/applications/mod_commands/mod_commands.c

@@ -5530,6 +5530,22 @@ SWITCH_STANDARD_API(escape_function)
 	return SWITCH_STATUS_SUCCESS;
 }
 
+SWITCH_STANDARD_API(quote_shell_arg_function)
+{
+	switch_memory_pool_t *pool;
+
+	if (zstr(cmd)) {
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+	switch_core_new_memory_pool(&pool);
+
+	stream->write_function(stream, "%s", switch_util_quote_shell_arg_pool(cmd, pool));
+
+	switch_core_destroy_memory_pool(&pool);
+	return SWITCH_STATUS_SUCCESS;
+}
+
 #define UUID_LOGLEVEL_SYNTAX "<uuid> <level>"
 SWITCH_STANDARD_API(uuid_loglevel)
 {
@@ -5999,6 +6015,7 @@ SWITCH_MODULE_LOAD_FUNCTION(mod_commands_load)
 	SWITCH_ADD_API(commands_api_interface, "nat_map", "Manage NAT", nat_map_function, "[status|republish|reinit] | [add|del] <port> [tcp|udp] [static]");
 	SWITCH_ADD_API(commands_api_interface, "originate", "Originate a call", originate_function, ORIGINATE_SYNTAX);
 	SWITCH_ADD_API(commands_api_interface, "pause", "Pause media on a channel", pause_function, PAUSE_SYNTAX);
+	SWITCH_ADD_API(commands_api_interface, "quote_shell_arg", "Quote/escape a string for use on shell command line", quote_shell_arg_function, "<data>");
 	SWITCH_ADD_API(commands_api_interface, "regex", "Evaluate a regex", regex_function, "<data>|<pattern>[|<subst string>]");
 	SWITCH_ADD_API(commands_api_interface, "reloadacl", "Reload XML", reload_acl_function, "");
 	SWITCH_ADD_API(commands_api_interface, "reload", "Reload module", reload_function, UNLOAD_SYNTAX);

src/switch_utils.c

@@ -2352,14 +2352,39 @@ SWITCH_DECLARE(char *) switch_string_replace(const char *string, const char *sea
 }
 
 SWITCH_DECLARE(char *) switch_util_quote_shell_arg(const char *string)
+{
+	return switch_util_quote_shell_arg_pool(string, NULL);
+}
+
+SWITCH_DECLARE(char *) switch_util_quote_shell_arg_pool(const char *string, switch_memory_pool_t *pool)
 {
 	size_t string_len = strlen(string);
 	size_t i;
 	size_t n = 0;
-	size_t dest_len = string_len + 1;	/* +1 for the opening quote  */
-	char *dest, *tmp;
+	size_t dest_len = 0;
+	char *dest;
 
-	dest = (char *) malloc(sizeof(char) * dest_len);
+	/* first pass through, figure out how large to make the allocation */
+	dest_len = strlen(string) + 1; /* string + null */
+	dest_len += 1; /* opening quote */
+	for (i = 0; i < string_len; i++) {
+		switch (string[i]) {
+#ifndef WIN32
+		case '\'':
+			/* We replace ' by sq dq sq dq sq, so need 4 additional bytes */
+			dest_len += 4;
+			break;
+#endif
+		}
+	}
+	dest_len += 1; /* closing quote */
+
+	/* if we're given a pool, allocate from it, otherwise use malloc */
+	if ( pool ) {
+		dest = switch_core_alloc(pool, sizeof(char) * dest_len);
+	} else {
+		dest = (char *) malloc(sizeof(char) * dest_len);
+	}
 	switch_assert(dest);
 
 #ifdef WIN32
@@ -2377,14 +2402,11 @@ SWITCH_DECLARE(char *) switch_util_quote_shell_arg(const char *string)
 			break;
 #else
 		case '\'':
-			/* We replace ' by '\'' */
-			dest_len += 3;
-			tmp = (char *) realloc(dest, sizeof(char) * (dest_len));
-			switch_assert(tmp);
-			dest = tmp;
+			/* We replace ' by sq dq sq dq sq */
 			dest[n++] = '\'';
-			dest[n++] = '\\';
+			dest[n++] = '"';
 			dest[n++] = '\'';
+			dest[n++] = '"';
 			dest[n++] = '\'';
 			break;
 #endif
@@ -2393,10 +2415,6 @@ SWITCH_DECLARE(char *) switch_util_quote_shell_arg(const char *string)
 		}
 	}
 
-	dest_len += 2;				/* +2 for the closing quote and the null character */
-	tmp = (char *) realloc(dest, sizeof(char) * (dest_len));
-	switch_assert(tmp);
-	dest = tmp;
 #ifdef WIN32
 	dest[n++] = '"';
 #else