add some error handling

modules/rtpproxy-ng/bencode.h

@@ -234,6 +234,11 @@ static inline char *bencode_dictionary_get_string(bencode_item_t *dict, const ch
  * may be NULL. */
 static inline char *bencode_dictionary_get_str(bencode_item_t *dict, const char *key, str *str);
 
+/* Looks up the given key in the dictionary and compares the corresponding value to the given
+ * null-terminated string. Returns 2 if the key isn't found or if the value isn't a string, otherwise
+ * returns according to strcmp(). */
+static inline int bencode_dictionary_get_strcmp(bencode_item_t *dict, const char *key, const char *str);
+
 /* Identical to bencode_dictionary_get() but returns the string in a newly allocated buffer (using the
  * BENCODE_MALLOC function), which remains valid even after bencode_buffer_t is destroyed. */
 static inline char *bencode_dictionary_get_string_dup(bencode_item_t *dict, const char *key, int *len);
@@ -375,5 +380,12 @@ static inline int bencode_strcmp(bencode_item_t *a, const char *b) {
 		return 1;
 	return memcmp(a->iov[1].iov_base, b, len);
 }
+static inline int bencode_dictionary_get_strcmp(bencode_item_t *dict, const char *key, const char *str) {
+	bencode_item_t *i;
+	i = bencode_dictionary_get(dict, key);
+	if (!i)
+		return 2;
+	return bencode_strcmp(i, str);
+}
 
 #endif

modules/rtpproxy-ng/rtpproxy.c

@@ -1093,6 +1093,12 @@ rtpp_test(struct rtpp_node *node, int isdisabled, int force)
 		goto error;
 	}
 
+	dict = bencode_decode_expect(&bencbuf, cp, ret, BENCODE_DICTIONARY);
+	if (!dict || bencode_dictionary_get_strcmp(dict, "result", "pong")) {
+		LM_ERR("proxy responded with invalid response\n");
+		goto error;
+	}
+
 	LM_INFO("rtp proxy <%s> found, support for it %senabled\n",
 	    node->rn_url.s, force == 0 ? "re-" : "");
 
@@ -1853,6 +1859,13 @@ force_rtp_proxy(struct sip_msg* msg, char* str1, char* str2, int offer, int forc
 		LM_ERR("failed to decode bencoded reply from proxy: %.*s\n", ret, cp);
 		goto error;
 	}
+	if (bencode_dictionary_get_strcmp(dict, "result", "ok")) {
+		if (!bencode_dictionary_get_str(dict, "error-reason", &newbody))
+			LM_ERR("proxy didn't give an \"ok\" response and didn't give an error reason: %.*s\n", ret, cp);
+		else
+			LM_ERR("proxy replied with error: %.*s\n", newbody.len, newbody.s);
+		goto error;
+	}
 
 	if (!bencode_dictionary_get_str_dup(dict, "sdp", &newbody)) {
 		LM_ERR("failed to extract sdp body from proxy reply: %.*s\n", ret, cp);