lost: additions to <via> path element and corrected loop detection

- LosT requests that allow recursion now include a <path> element that
  contains one or more <via> elements. A loop error is indicated if a
  returned target is already in the server list in the <path> element.

src/modules/lost/functions.c

@@ -819,7 +819,9 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 	str req = STR_NULL;
 	str con = STR_NULL;
 	str ret = STR_NULL;
+	str src = STR_NULL;
 	str pidf = STR_NULL;
+	str rereq = STR_NULL;
 	str oldurl = STR_NULL;
 	str losturl = STR_NULL;
 
@@ -1063,9 +1065,8 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 		goto err;
 	}
 	/* assemble findService request */
-	req.s = lost_find_service_request(loc, &req.len);
-	lost_free_loc(&loc); /* clean up */
-
+	req.s = lost_find_service_request(loc, NULL, &req.len);
+
 	if(req.s == NULL && req.len == 0) {
 		LM_ERR("lost request failed\n");
 		goto err;
@@ -1113,7 +1114,7 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 
 	LM_DBG("findService response: [%.*s]\n", ret.len, ret.s);
 
-	/* at least parse one request */
+	/* at least parse one response */
 	redirect = 1;
 	while(redirect) {
 		fsrdata = lost_parse_findServiceResponse(ret);
@@ -1186,6 +1187,39 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 						tmp.len = strlen(fsrdata->redirect->target);
 						url.s = &(ustr[0]);
 						url.len = MAX_URI_SIZE;
+						/* check loop ... current response */
+						if(oldurl.s != NULL && oldurl.len > 0) {
+							if(str_strcasecmp(&tmp, &oldurl) == 0) {
+								LM_ERR("loop detected: "
+									   "[%.*s]<-->[%.*s]\n",
+										oldurl.len, oldurl.s, tmp.len, tmp.s);
+								goto err;
+							}
+						}
+						/* add redirecting source to path list */
+						if((src.s = fsrdata->redirect->source) != NULL) {
+							src.len = strlen(fsrdata->redirect->source);
+      				if(lost_append_response_list(&fsrdata->path, src) == 0) {
+			  				LM_ERR("could not append server to path elememt\n");
+				  			goto err;
+					  	}
+						}
+						/* clean up */
+						src.s = NULL;
+						src.len = 0;
+						/* check loop ... path elements */
+						char *via = NULL;
+						if(lost_search_response_list(&fsrdata->path, &via, tmp.s) > 0) {
+							LM_ERR("loop detected: "
+								   "[%s]<-->[%.*s]\n",
+									via, tmp.len, tmp.s);
+							goto err;
+						}
+						/* remember the redirect target */
+						if(pkg_str_dup(&oldurl, &tmp) < 0) {
+							LM_ERR("could not copy: [%.*s]\n", tmp.len, tmp.s);
+							goto err;
+						}
 						/* get url string via NAPTR */
 						naptr = lost_naptr_lookup(tmp, &shttps, &url);
 						if(naptr == 0) {
@@ -1200,23 +1234,15 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 						/* clean up */
 						tmp.s = NULL;
 						tmp.len = 0;
-						/* check loop */
-						if(oldurl.s != NULL && oldurl.len > 0) {
-							if(str_strcasecmp(&url, &oldurl) == 0) {
-								LM_ERR("loop detected: "
-									   "[%.*s]<-->[%.*s]\n",
-										oldurl.len, oldurl.s, url.len, url.s);
-								goto err;
-							}
-						}
-						/* remember the redirect target */
-						if(pkg_str_dup(&oldurl, &url) < 0) {
-							LM_ERR("could not copy: [%.*s]\n", url.len, url.s);
-							goto err;
-						}
+
+						/* assemble new findService request including path element */
+						rereq.s = lost_find_service_request(loc, fsrdata->path, &rereq.len);
 						/* clean up */
 						lost_free_findServiceResponse(&fsrdata);
 						lost_free_string(&ret);
+
+						LM_DBG("findService request: [%.*s]\n", rereq.len, rereq.s);
+
 						/* copy url */
 						len = 0;
 						urlrep = lost_copy_string(url, &len);
@@ -1226,9 +1252,12 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 						}
 						/* send request */
 						curl = httpapi.http_client_query(
-								_m, urlrep, &ret, req.s, mtlost);
-						pkg_free(urlrep); /*clean up */
+								_m, urlrep, &ret, rereq.s, mtlost);
+						/*clean up */
+						pkg_free(urlrep);
 						urlrep = NULL;
+						lost_free_string(&rereq);
+
 						/* only HTTP 2xx responses are accepted */
 						if(curl >= 300 || curl < 100) {
 							LM_ERR("POST [%.*s] failed with error: %d\n",
@@ -1260,6 +1289,7 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 	lost_free_string(&ret);
 	lost_free_string(&req);
 	lost_free_string(&oldurl);
+	lost_free_loc(&loc);
 
 	/* set writable pvars */
 	pvname.rs = name;
@@ -1310,6 +1340,9 @@ int lost_function(struct sip_msg *_m, char *_con, char *_uri, char *_name,
 	if(req.s != NULL && req.len > 0) {
 		lost_free_string(&req);
 	}
+	if(rereq.s != NULL && rereq.len > 0) {
+		lost_free_string(&rereq);
+	}
 	if(name.s != NULL && name.len > 0) {
 		lost_free_string(&name);
 	}

src/modules/lost/response.c

@@ -353,6 +353,35 @@ void lost_reverse_response_list(p_lost_list_t *head)
 	*head = prev;
 }
 
+/*
+ * lost_append_response_list(list, str)
+ * appends str value to list object and returns str len
+ */
+int lost_append_response_list(p_lost_list_t *head, str val)
+{
+	int len = 0;
+	p_lost_list_t new = NULL;
+	p_lost_list_t current = *head;
+
+	new = lost_new_response_list();
+	if (new != NULL) {
+		new->value = lost_copy_string(val, &len);
+		new->next = NULL;
+
+		LM_DBG("### new list data [%.*s]\n", val.len, val.s);
+
+		if (current == NULL) {
+			*head = new;
+			return len;
+		}
+		while (current->next != NULL) {
+			current = current->next;
+		}
+		current->next = new;
+	}
+	return len;
+}
+
 /*
  * lost_search_response_list(list, value, search)
  * looks for search string in list object and returns pointer if found

src/modules/lost/response.h

@@ -121,7 +121,9 @@ typedef struct lost_fsr
 /* read and parse response data */
 p_lost_fsr_t lost_parse_findServiceResponse(str);
 /* check response to dereferece request */
-int lost_check_HeldResponse(xmlNodePtr); 
+int lost_check_HeldResponse(xmlNodePtr);
+/* appends value to list objects */
+int lost_append_response_list(p_lost_list_t *, str);
 /* print the response */
 void lost_print_findServiceResponse(p_lost_fsr_t);
 /* remove response data from memory */

src/modules/lost/utilities.c

@@ -48,6 +48,7 @@
 
 #include "pidf.h"
 #include "utilities.h"
+#include "response.h"
 
 extern int lost_recursion;
 extern int lost_profile;
@@ -1492,10 +1493,48 @@ char *lost_held_location_request(p_lost_held_t held, int *lgth)
 }
 
 /*
- * lost_find_service_request(loc, lgth)
+ * lost_append_via_element(head, parent)
+ * appends via elements and returns the number of via elements added
+ */
+int lost_append_via_element(p_lost_list_t *head, xmlNodePtr *parent)
+{
+	int cnt = 0;
+	int i;
+	p_lost_list_t current = NULL;
+
+	if (head == NULL) {
+		return 0;
+	}
+
+	/* at least one <via> element to add */
+	current = *head;
+	cnt++;
+
+	/* check for more <via> elements to add */
+	while (current->next != NULL) {
+		cnt++;
+		current = current->next;
+	}
+
+	current = *head;
+	xmlNodePtr ptrVia[cnt];
+
+	/* ad <via> elements to <path> element */
+	for (i = 0; i < cnt; i++) {
+		ptrVia[i] = xmlNewChild(*parent, NULL, BAD_CAST "via", NULL);
+		xmlNewProp(ptrVia[i], BAD_CAST "source", BAD_CAST current->value);
+		current = current->next;
+	}
+
+	return cnt;
+}
+
+
+/*
+ * lost_find_service_request(loc, path, lgth)
  * assembles and returns findService request string (allocated in private memory)
  */
-char *lost_find_service_request(p_lost_loc_t loc, int *lgth)
+char *lost_find_service_request(p_lost_loc_t loc, p_lost_list_t path, int *lgth)
 {
 	int buffersize = 0;
 
@@ -1511,6 +1550,7 @@ char *lost_find_service_request(p_lost_loc_t loc, int *lgth)
 	xmlNodePtr ptrCircle = NULL;
 	xmlNodePtr ptrRadius = NULL;
 	xmlNodePtr ptrNode = NULL;
+	xmlNodePtr ptrPath = NULL;
 
 	xmlKeepBlanksDefault(1);
 
@@ -1531,6 +1571,10 @@ char *lost_find_service_request(p_lost_loc_t loc, int *lgth)
         </p2:Point>
     </location>
     <service>urn:service:sos.police</service>
+		<path>
+			<via source="resolver.example"/>
+			<via source="authoritative.example"/>
+		</path>
 </findService>
  */
 	/* create request */
@@ -1623,6 +1667,20 @@ char *lost_find_service_request(p_lost_loc_t loc, int *lgth)
 	/* service - element */
 	snprintf(buf, BUFSIZE, "%s", loc->urn);
 	xmlNewChild(ptrFindService, NULL, BAD_CAST "service", BAD_CAST buf);
+	/* service - element */
+	if (path != NULL) {
+		ptrPath = xmlNewChild(ptrFindService, NULL, BAD_CAST "path", NULL);
+		if(ptrPath == NULL) {
+			LM_ERR("locationRequest xmlNewChild() failed\n");
+			xmlFreeDoc(request);
+			return doc;
+		}
+		if (lost_append_via_element(&path, &ptrPath) == 0) {
+			LM_ERR("appending <via> elements to <path> failed\n");
+			xmlFreeDoc(request);
+			return doc;
+		}
+	}
 
 	xmlDocDumpFormatMemory(request, &xmlbuff, &buffersize, 0);
 	if(xmlbuff == NULL) {

src/modules/lost/utilities.h

@@ -32,6 +32,8 @@
 #ifndef LOST_UTILITIES_H
 #define LOST_UTILITIES_H
 
+#include "response.h"
+
 #define LAQUOT '<'
 #define COLON ':'
 
@@ -132,7 +134,7 @@ int lost_parse_host(const char *, str *, int *);
 int lost_new_geoheader_list(p_lost_geolist_t *, str);
 int lost_get_nameinfo(char *, str *, int);
 
-char *lost_find_service_request(p_lost_loc_t, int *);
+char *lost_find_service_request(p_lost_loc_t, p_lost_list_t, int *);
 char *lost_held_location_request(p_lost_held_t, int *);
 char *lost_held_post_request(int *, long, char *);
 char *lost_get_content(xmlNodePtr, const char *, int *);