drouting: Fix rule fallback across multiple prefixless rules ('')

Mostly affects the "do_routing() + use_next_gw()" scripting logic.

(cherry picked from commit fd5066a)
(cherry picked from commit 435aa4b)

modules/drouting/dr_api_internal.c

@@ -71,7 +71,7 @@ static inline void * get_qr_rule_handle(rt_info_t *rule) {
 rt_info_t* find_rule_by_prefix_unsafe(ptree_t *pt, ptree_node_t *noprefix,
 		str prefix, unsigned int grp_id, unsigned int *matched_len)
 {
-	unsigned int rule_idx = 0;
+	int rule_idx = 0;
 	rt_info_t *rt_info;
 
 	rt_info = get_prefix(pt, &prefix, grp_id,matched_len, &rule_idx);

modules/drouting/drouting.c

@@ -3127,7 +3127,7 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 	pgw_list_t *dst, *cdst;
 	pgw_list_t *wl_list;
 	unsigned int prefix_len;
-	unsigned int rule_idx;
+	int rule_idx;
 	struct head_db *current_partition=NULL;
 	unsigned short wl_len;
 	str username;
@@ -3258,7 +3258,7 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 		}
 		username = val.s;
 		/* still something to look for ? */
-		if (username.len==0) return -1;
+		if (username.len==0 && rule_idx<0) return -1;
 
 		/* original RURI to be used when building RURIs for new attempts */
 		if (search_first_avp( AVP_VAL_STR, current_partition->avpID_store_ruri,
@@ -3289,7 +3289,7 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 		username.len = prefix_len -(rule_idx?0:1);
 		LM_DBG("doing internal fallback, prefix_len=%d,rule_idx=%d\n",
 				username.len, rule_idx);
-		if (username.len==0 && rule_idx==0) {
+		if (username.len==0 && rule_idx<=0) {
 			/* disable failover as nothing left */
 			flags = flags & ~DR_PARAM_RULE_FALLBACK;
 			goto error2;
@@ -3306,18 +3306,24 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 	}
 
 	if (rt_info==0) {
-		LM_DBG("no matching for prefix \"%.*s\"\n",
-				username.len, username.s);
+		LM_DBG("no matching for prefix \"%.*s\" idx: %d\n",
+				username.len, username.s, rule_idx);
 		/* try prefixless rules */
-		rt_info = check_rt(&current_partition->rdata->noprefix,
-				(unsigned int)grp);
+		if (rule_idx >= 0)
+			rt_info = _check_rt(&current_partition->rdata->noprefix,
+					(unsigned int)grp, &rule_idx);
 		if (rt_info==0) {
 			LM_DBG("no prefixless matching for "
 					"grp %d\n", grp);
 			goto error2;
 		}
 		prefix_len = 0;
-		rule_idx = 0;
+
+		LM_DBG("prefixless matching successful, crt-index: %d\n", rule_idx);
+
+		/* "stop" marker for reaching the last prefixless route */
+		if (rule_idx == 0)
+			rule_idx = -1;
 	}
 
 	if (rt_info->route_idx && (rt_idx=get_script_route_ID_by_name
@@ -3336,7 +3342,7 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 		goto no_gws;
 
 	/* do we have anything left to failover to ? */
-	if (prefix_len==0 && rule_idx==0)
+	if (prefix_len==0 && rule_idx<=0)
 		/* disable failover as nothing left */
 		flags = flags & ~DR_PARAM_RULE_FALLBACK;
 
@@ -3548,10 +3554,9 @@ static int do_routing(struct sip_msg* msg, struct head_db *part, int grp,
 		if ( !(flags & DR_PARAM_INTERNAL_TRIGGERED) ) {
 			/* first time - we need to save some date, to be able to
 			 * do the rule fallback later in "next_gw" , but do it only if 
-			 * there is place for fallback (more rules or shorter prefix are 
-			 * available) */
-			if (prefix_len!=0 || rule_idx!=0) {
-				LM_DBG("saving rule_idx %d, prefix %.*s\n",rule_idx,
+			 * there is room for fallback (more rules are available) */
+			if (rule_idx>0) {
+				LM_DBG("saving rule_idx %d, prefix '%.*s'\n",rule_idx,
 						prefix_len - (rule_idx?0:1), username.s);
 				val.n = rule_idx;
 				if (add_avp( 0 , current_partition->avpID_store_index, val) ) {

modules/drouting/prefix_tree.c

@@ -84,7 +84,7 @@ static inline rt_info_t*
 internal_check_rt(
 		ptree_node_t *ptn,
 		unsigned int rgid,
-		unsigned int *rgidx
+		int *rgidx
 		)
 {
 	int i,j;
@@ -126,18 +126,28 @@ check_rt(
 	unsigned int rgid
 	)
 {
-	unsigned int rgidx = 0;
+	int rgidx = 0;
 	return internal_check_rt( ptn, rgid, &rgidx);
 }
 
+rt_info_t*
+_check_rt(
+	ptree_node_t *ptn,
+	unsigned int rgid,
+	int *rgidx
+	)
+{
+	return internal_check_rt( ptn, rgid, rgidx);
+}
+
 
 rt_info_t*
 get_prefix(
 	ptree_t *ptree,
 	str* prefix,
 	unsigned int rgid,
 	unsigned int *matched_len,
-	unsigned int *rgidx
+	int *rgidx
 	)
 {
 	rt_info_t *rt = NULL;
@@ -147,7 +157,7 @@ get_prefix(
 
 	if(NULL == ptree)
 		goto err_exit;
-	if(NULL == prefix)
+	if(NULL == prefix || prefix->len == 0)
 		goto err_exit;
 	tmp = prefix->s;
 	if (tmp == NULL)

modules/drouting/prefix_tree.h

@@ -203,8 +203,8 @@ get_prefix(
 	ptree_t *ptree,
 	str* prefix,
 	unsigned int rgid,
-	unsigned int *rgidx,
-	unsigned int *matched_len
+	unsigned int *matched_len,
+	int *rgidx
 	);
 
 int
@@ -255,4 +255,11 @@ check_rt(
 	unsigned int rgid
 	);
 
+rt_info_t*
+_check_rt(
+	ptree_node_t *ptn,
+	unsigned int rgid,
+	int *rgidx
+	);
+
 #endif