let the circuit-launcher choose the exit node (if he wants)

svn:r1428

src/or/circuit.c

@@ -15,7 +15,7 @@ static void circuit_rep_hist_note_result(circuit_t *circ);
 
 static void circuit_is_ready(circuit_t *circ);
 static void circuit_failed(circuit_t *circ);
-static circuit_t *circuit_establish_circuit(uint8_t purpose);
+static circuit_t *circuit_establish_circuit(uint8_t purpose, const char *exit_nickname);
 
 unsigned long stats_n_relay_cells_relayed = 0;
 unsigned long stats_n_relay_cells_delivered = 0;
@@ -1052,7 +1052,7 @@ static void circuit_failed(circuit_t *circ) {
 static int n_circuit_failures = 0;
 
 /* Launch a new circuit and return a pointer to it. Return NULL if you failed. */
-circuit_t *circuit_launch_new(uint8_t purpose) {
+circuit_t *circuit_launch_new(uint8_t purpose, const char *exit_nickname) {
 
   if(!(options.SocksPort||options.RunTesting)) /* no need for circuits. */
     return NULL;
@@ -1063,7 +1063,7 @@ circuit_t *circuit_launch_new(uint8_t purpose) {
   }
 
   /* try a circ. if it fails, circuit_mark_for_close will increment n_circuit_failures */
-  return circuit_establish_circuit(purpose);
+  return circuit_establish_circuit(purpose, exit_nickname);
 }
 
 void circuit_increment_failure_count(void) {
@@ -1075,14 +1075,15 @@ void circuit_reset_failure_count(void) {
   n_circuit_failures = 0;
 }
 
-static circuit_t *circuit_establish_circuit(uint8_t purpose) {
+static circuit_t *circuit_establish_circuit(uint8_t purpose,
+                                            const char *exit_nickname) {
   routerinfo_t *firsthop;
   connection_t *n_conn;
   circuit_t *circ;
 
   circ = circuit_new(0, NULL); /* sets circ->p_circ_id and circ->p_conn */
   circ->state = CIRCUIT_STATE_OR_WAIT;
-  circ->build_state = onion_new_cpath_build_state();
+  circ->build_state = onion_new_cpath_build_state(exit_nickname);
   circ->purpose = purpose;
 
   if (! circ->build_state) {

src/or/connection_edge.c

@@ -758,7 +758,7 @@ static int connection_ap_handshake_attach_circuit(connection_t *conn,
     case 0: /* no useful circuits available */
       if(!circuit_get_newest(conn, 0, must_be_clean)) {
         /* is one already on the way? */
-        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL);
+        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL, NULL);
       }
       return 0;
     default: /* case 1, it succeeded, great */

src/or/main.c

@@ -391,11 +391,12 @@ static void run_scheduled_events(time_t now) {
       circuit_reset_failure_count();
       if(circ && circ->timestamp_dirty) {
         log_fn(LOG_INFO,"Youngest circuit dirty; launching replacement.");
-        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL); /* make a new circuit */
+        /* make a new circuit */
+        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL, NULL);
       } else if (options.RunTesting && circ &&
                  circ->timestamp_created + TESTING_CIRCUIT_INTERVAL < now) {
         log_fn(LOG_INFO,"Creating a new testing circuit.");
-        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL);
+        circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL, NULL);
       }
       time_to_new_circuit = now + options.NewCircuitPeriod;
     }
@@ -404,7 +405,7 @@ static void run_scheduled_events(time_t now) {
       /* if there's no open circ, and less than 3 are on the way,
        * go ahead and try another.
        */
-      circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL);
+      circuit_launch_new(CIRCUIT_PURPOSE_C_GENERAL, NULL);
     }
   }
 

src/or/onion.c

@@ -347,7 +347,7 @@ static routerinfo_t *choose_good_exit_server(routerlist_t *dir)
   return NULL;
 }
 
-cpath_build_state_t *onion_new_cpath_build_state(void) {
+cpath_build_state_t *onion_new_cpath_build_state(const char *exit_nickname) {
   routerlist_t *rl;
   int r;
   cpath_build_state_t *info;
@@ -357,12 +357,19 @@ cpath_build_state_t *onion_new_cpath_build_state(void) {
   r = new_route_len(options.PathlenCoinWeight, rl->routers, rl->n_routers);
   if (r < 0)
     return NULL;
-  exit = choose_good_exit_server(rl);
-  if(!exit)
-    return NULL;
   info = tor_malloc(sizeof(cpath_build_state_t));
   info->desired_path_len = r;
-  info->chosen_exit = tor_strdup(exit->nickname);
+  if(exit_nickname) { /* the circuit-builder pre-requested one */
+    log_fn(LOG_INFO,"Using requested exit node '%s'", exit_nickname);
+    info->chosen_exit = tor_strdup(exit_nickname);
+  } else { /* we have to decide one */
+    exit = choose_good_exit_server(rl);
+    if(!exit) {
+      tor_free(info);
+      return NULL;
+    }
+    info->chosen_exit = tor_strdup(exit->nickname);
+  }
   return info;
 }
 

src/or/or.h

@@ -689,7 +689,7 @@ void circuit_log_path(int severity, circuit_t *circ);
 void circuit_dump_by_conn(connection_t *conn, int severity);
 
 void circuit_expire_unused_circuits(void);
-circuit_t *circuit_launch_new(uint8_t purpose);
+circuit_t *circuit_launch_new(uint8_t purpose, const char *exit_nickname);
 void circuit_increment_failure_count(void);
 void circuit_reset_failure_count(void);
 void circuit_n_conn_open(connection_t *or_conn);
@@ -916,7 +916,7 @@ int onion_skin_client_handshake(crypto_dh_env_t *handshake_state,
                              char *key_out,
                              int key_out_len);
 
-cpath_build_state_t *onion_new_cpath_build_state(void);
+cpath_build_state_t *onion_new_cpath_build_state(const char *exit_nickname);
 
 /********************************* router.c ***************************/
 

src/or/rendservice.c

@@ -363,7 +363,7 @@ int rend_services_init(void) {
 
     // for each intro point,
     {
-      circ = circuit_launch_new(CIRCUIT_PURPOSE_S_ESTABLISH_INTRO);
+      //circ = circuit_launch_new(CIRCUIT_PURPOSE_S_ESTABLISH_INTRO, intro->nickname);
       // tell circ which hidden service this is about
     }