add in directory 'post' support

svn:r471

src/or/buffers.c

@@ -189,6 +189,74 @@ int fetch_from_buf(char *string, int string_len,
   return *buf_datalen;
 }
 
+/* There is a (possibly incomplete) http statement on *buf, of the
+ * form "%s\r\n\r\n%s", headers, body.
+ * If a) the headers include a Content-Length field and all bytes in
+ * the body are present, or b) there's no Content-Length field and
+ * all headers are present, then:
+ *   copy headers and body into the supplied args (and null terminate
+ *   them), remove them from buf, and return 1.
+ *   (If headers or body is NULL, discard that part of the buf.)
+ *   If a headers or body doesn't fit in the arg, return -1.
+ * 
+ * Else, change nothing and return 0.
+ */
+int fetch_from_buf_http(char *buf, int *buf_datalen,
+                        char *headers_out, int max_headerlen,
+                        char *body_out, int max_bodylen) {
+  char *headers, *body;
+  int i;
+  int headerlen, bodylen, contentlen;
+
+  assert(buf && buf_datalen);
+
+  headers = buf;
+  i = find_on_inbuf("\r\n\r\n", 4, buf, *buf_datalen);
+  if(i < 0) {
+    log_fn(LOG_DEBUG,"headers not all here yet.");
+    return 0;
+  }
+  body = buf+i;
+  headerlen = body-headers; /* includes the CRLFCRLF */
+  bodylen = *buf_datalen - headerlen;
+  log_fn(LOG_DEBUG,"headerlen %d, bodylen %d.",headerlen,bodylen);
+
+  if(headers_out && max_headerlen <= headerlen) {
+    log_fn(LOG_DEBUG,"headerlen %d larger than %d. Failing.", headerlen, max_headerlen-1);
+    return -1;
+  }
+  if(body_out && max_bodylen <= bodylen) {
+    log_fn(LOG_DEBUG,"bodylen %d larger than %d. Failing.", bodylen, max_bodylen-1);
+    return -1;
+  }
+
+#define CONTENT_LENGTH "Content-Length: "
+  i = find_on_inbuf(CONTENT_LENGTH, strlen(CONTENT_LENGTH), headers, headerlen);
+  /* This includes headers like Not-Content-Length. But close enough. */
+  if(i > 0) {
+    contentlen = atoi(headers+i);
+    if(bodylen < contentlen) {
+      log_fn(LOG_DEBUG,"body not all here yet.");
+      return 0; /* not all there yet */
+    }
+    bodylen = contentlen;
+    log_fn(LOG_DEBUG,"bodylen reduced to %d.",bodylen);
+  }
+  /* all happy. copy into the appropriate places, and return 1 */
+  if(headers_out) {
+    memcpy(headers_out,buf,headerlen);
+    headers_out[headerlen] = 0; /* null terminate it */
+  }
+  if(body_out) {
+    memcpy(body_out,buf+headerlen,bodylen);
+    body_out[bodylen] = 0; /* null terminate it */
+  }
+  *buf_datalen -= (headerlen+bodylen);
+  memmove(buf, buf+headerlen+bodylen, *buf_datalen);
+
+  return 1;
+}
+
 int find_on_inbuf(char *string, int string_len,
                   char *buf, int buf_datalen) {
   /* find first instance of needle 'string' on haystack 'buf'. return how

src/or/connection.c

@@ -230,7 +230,7 @@ static int connection_init_accepted_conn(connection_t *conn) {
       conn->state = AP_CONN_STATE_SOCKS_WAIT;
       break;
     case CONN_TYPE_DIR:
-      conn->state = DIR_CONN_STATE_COMMAND_WAIT;
+      conn->state = DIR_CONN_STATE_SERVER_COMMAND_WAIT;
       break;
   }
   return 0;
@@ -438,7 +438,8 @@ int connection_handle_read(connection_t *conn) {
   }
 
   if(connection_read_to_buf(conn) < 0) {
-    if(conn->type == CONN_TYPE_DIR && conn->state == DIR_CONN_STATE_CONNECTING) {
+    if(conn->type == CONN_TYPE_DIR && 
+      (conn->state == DIR_CONN_STATE_CONNECTING_GET || DIR_CONN_STATE_CONNECTING_POST)) {
        /* it's a directory server and connecting failed: forget about this router */
        /* XXX I suspect pollerr may make Windows not get to this point. :( */
        router_forget_router(conn->addr,conn->port); 
@@ -526,6 +527,13 @@ int connection_fetch_from_buf(char *string, int len, connection_t *conn) {
   return fetch_from_buf(string, len, &conn->inbuf, &conn->inbuflen, &conn->inbuf_datalen);
 }
 
+int connection_fetch_from_buf_http(connection_t *conn,
+                                   char *headers_out, int max_headerlen,
+                                   char *body_out, int max_bodylen) {
+  return fetch_from_buf_http(conn->inbuf,&conn->inbuf_datalen,
+                             headers_out, max_headerlen, body_out, max_bodylen);
+}
+
 int connection_find_on_inbuf(char *string, int len, connection_t *conn) {
   return find_on_inbuf(string, len, conn->inbuf, conn->inbuf_datalen);
 }

src/or/directory.c

@@ -6,10 +6,9 @@
 
 #define MAX_DIR_SIZE 50000 /* XXX, big enough? */
 
-static int directory_send_command(connection_t *conn);
+static int directory_send_command(connection_t *conn, int command);
 static void directory_rebuild(void);
 static int directory_handle_command(connection_t *conn);
-static int directory_handle_reading(connection_t *conn);
 
 /********* START VARIABLES **********/
 
@@ -17,7 +16,6 @@ extern or_options_t options; /* command-line and config-file options */
 
 static char the_directory[MAX_DIR_SIZE+1];
 static int directorylen=0;
-static int reading_headers=0;
 static int directory_dirty=1;
 
 static char getstring[] = "GET / HTTP/1.0\r\n\r\n";
@@ -26,18 +24,21 @@ static char answerstring[] = "HTTP/1.0 200 OK\r\n\r\n";
 
 /********* END VARIABLES ************/
 
-void directory_initiate_fetch(routerinfo_t *router) {
+void directory_initiate_command(routerinfo_t *router, int command) {
   connection_t *conn;
 
   if(!router) /* i guess they didn't have one in mind for me to use */
     return;
 
-  if(connection_get_by_type(CONN_TYPE_DIR)) { /* there's already a fetch running */
-    log_fn(LOG_DEBUG,"Canceling fetch, dir conn already active.");
+  if(connection_get_by_type(CONN_TYPE_DIR)) { /* there's already a dir conn running */
+    log_fn(LOG_DEBUG,"Canceling connect, dir conn already active.");
     return;
   }
 
-  log_fn(LOG_DEBUG,"initiating directory fetch");
+  if(command == DIR_CONN_STATE_CONNECTING_GET)
+    log_fn(LOG_DEBUG,"initiating directory get");
+  else
+    log_fn(LOG_DEBUG,"initiating directory post");
 
   conn = connection_new(CONN_TYPE_DIR);
   if(!conn)
@@ -52,7 +53,7 @@ void directory_initiate_fetch(routerinfo_t *router) {
   if (router->signing_pkey)
     conn->pkey = crypto_pk_dup_key(router->signing_pkey);
   else {
-    log_fn(LOG_ERR, "No signing key known for directory %s; signature won't be checked", conn->address);
+    log_fn(LOG_ERR, "No signing key known for dirserver %s; signature won't be checked", conn->address);
     conn->pkey = NULL;
   }
 
@@ -63,7 +64,7 @@ void directory_initiate_fetch(routerinfo_t *router) {
 
   switch(connection_connect(conn, router->address, router->addr, router->dir_port)) {
     case -1:
-      router_forget_router(conn->addr, conn->port); /* don't try him again */
+      router_forget_router(conn->addr, conn->port); /* XXX don't try him again */
       connection_free(conn);
       return;
     case 0:
@@ -71,28 +72,45 @@ void directory_initiate_fetch(routerinfo_t *router) {
       connection_watch_events(conn, POLLIN | POLLOUT | POLLERR);
       /* writable indicates finish, readable indicates broken link,
          error indicates broken link in windowsland. */
-      conn->state = DIR_CONN_STATE_CONNECTING;
+      conn->state = command;
       return;
     /* case 1: fall through */
   }
 
   connection_set_poll_socket(conn);
-  if(directory_send_command(conn) < 0) {
+  if(directory_send_command(conn, command) < 0) {
     connection_remove(conn);
     connection_free(conn);
   }
 }
 
-static int directory_send_command(connection_t *conn) {
+static int directory_send_command(connection_t *conn, int command) {
+  char *s;
 
   assert(conn && conn->type == CONN_TYPE_DIR);
 
-  if(connection_write_to_buf(getstring, strlen(getstring), conn) < 0) {
-    log_fn(LOG_DEBUG,"Couldn't write command to buffer.");
-    return -1;
+  switch(command) {
+    case DIR_CONN_STATE_CONNECTING_GET:
+      if(connection_write_to_buf(getstring, strlen(getstring), conn) < 0) {
+        log_fn(LOG_DEBUG,"Couldn't write get to buffer.");
+        return -1;
+      }
+      conn->state = DIR_CONN_STATE_CLIENT_SENDING_GET;
+      break;
+    case DIR_CONN_STATE_CONNECTING_POST:
+      s = router_get_my_descriptor();
+      if(!s) {
+        log_fn(LOG_DEBUG,"Failed to get my descriptor.");
+        return -1;
+      }
+      if(connection_write_to_buf(poststring, strlen(poststring), conn) < 0 ||
+         connection_write_to_buf(s, strlen(s), conn) < 0) {
+        log_fn(LOG_DEBUG,"Couldn't write post/descriptor to buffer.");
+        return -1;
+      }
+      conn->state = DIR_CONN_STATE_CLIENT_SENDING_POST;
+      break;
   }
-
-  conn->state = DIR_CONN_STATE_SENDING_COMMAND;
   return 0;
 }
 
@@ -107,8 +125,8 @@ static void directory_rebuild(void) {
       log(LOG_ERR, "Error writing directory");
       return;
     }
-    log(LOG_INFO,"New directory:\n%s",the_directory);
     directorylen = strlen(the_directory);
+    log(LOG_INFO,"New directory (size %d):\n%s",directorylen,the_directory);
     directory_dirty = 0;
   } else {
     log(LOG_INFO,"Directory still clean, reusing.");
@@ -120,111 +138,101 @@ int connection_dir_process_inbuf(connection_t *conn) {
   assert(conn && conn->type == CONN_TYPE_DIR);
 
   if(conn->inbuf_reached_eof) {
-    if(conn->state != DIR_CONN_STATE_READING) {
-      log_fn(LOG_DEBUG,"conn reached eof, not reading. Closing.");
-      return -1;
-    }
-    /* eof reached, kill it, but first process the_directory and learn about new routers. */
-    log_fn(LOG_DEBUG,"Received directory (size %d)\n%s", directorylen, the_directory);
-    if(directorylen == 0) {
-      log_fn(LOG_DEBUG,"Empty directory. Ignoring.");
-      return -1;
-    }
-    if(router_get_dir_from_string(the_directory, conn->pkey) < 0) {
-      log_fn(LOG_DEBUG,"...but parsing failed. Ignoring.");
-    } else {
-      log_fn(LOG_DEBUG,"and got an %s directory; updated routers.", 
-          conn->pkey ? "authenticated" : "unauthenticated");
-    }
-
-    if(options.OnionRouter) { /* connect to them all */
-      router_retry_connections();
+    switch(conn->state) {
+      case DIR_CONN_STATE_CLIENT_READING_GET:
+        /* kill it, but first process the_directory and learn about new routers. */
+        switch(connection_fetch_from_buf_http(conn, NULL, 0, the_directory, MAX_DIR_SIZE)) {
+          case -1: /* overflow */
+            log_fn(LOG_DEBUG,"'get' response too large. Failing.");
+            return -1;
+          case 0:
+            log_fn(LOG_DEBUG,"'get' response not all here, but we're at eof. Closing.");
+            return -1;
+          /* case 1, fall through */
+        }
+        directorylen = strlen(the_directory);
+        log_fn(LOG_DEBUG,"Received directory (size %d):\n%s", directorylen, the_directory);
+        if(directorylen == 0) {
+          log_fn(LOG_DEBUG,"Empty directory. Ignoring.");
+          return -1;
+        }
+        if(router_get_dir_from_string(the_directory, conn->pkey) < 0) {
+          log_fn(LOG_DEBUG,"...but parsing failed. Ignoring.");
+        } else {
+          log_fn(LOG_DEBUG,"and got an %s directory; updated routers.", 
+              conn->pkey ? "authenticated" : "unauthenticated");
+        }
+        if(options.OnionRouter) { /* connect to them all */
+          router_retry_connections();
+        }
+        return -1;
+      case DIR_CONN_STATE_CLIENT_READING_POST:
+        /* XXX make sure there's a 200 OK on the buffer */
+        log_fn(LOG_DEBUG,"eof while reading post response. Finished.");
+        return -1;
+      default:
+        log_fn(LOG_DEBUG,"conn reached eof, not reading. Closing.");
+        return -1;
     }
-    return -1;
   }
 
-  switch(conn->state) {
-    case DIR_CONN_STATE_COMMAND_WAIT:
-      return directory_handle_command(conn);
-    case DIR_CONN_STATE_READING:
-      return directory_handle_reading(conn);
-    default:
-      log_fn(LOG_DEBUG,"Got data while writing; Ignoring.");
-      break;
-  }
+  if(conn->state == DIR_CONN_STATE_SERVER_COMMAND_WAIT)
+    return directory_handle_command(conn);
+
+  /* XXX for READ states, might want to make sure inbuf isn't too big */
 
+  log_fn(LOG_DEBUG,"Got data, not eof. Leaving on inbuf.");
   return 0;
 }
 
 static int directory_handle_command(connection_t *conn) {
-  char buf[15];
+  char headers[1024];
+  char body[1024];
 
   assert(conn && conn->type == CONN_TYPE_DIR);
 
-  if(conn->inbuf_datalen < (int)strlen(getstring)) { /* entire response available? */
-    log_fn(LOG_DEBUG,"Entire command not here yet. Waiting.");
-    return 0; /* not yet */
-  }
-
-  connection_fetch_from_buf(buf,strlen(getstring),conn);
-
-  if(strncasecmp(buf,getstring,strlen("GET / HTTP/"))) {
-    log_fn(LOG_DEBUG,"Command doesn't seem to be a get. Closing,");
-    return -1;
-  }
-
-  directory_rebuild(); /* rebuild it now, iff it's dirty */
-
-  if(directorylen == 0) {
-    log_fn(LOG_DEBUG,"My directory is empty. Closing.");
-    return -1;
-  }
-
-  log_fn(LOG_DEBUG,"Dumping directory to client."); 
-  if((connection_write_to_buf(answerstring, strlen(answerstring), conn) < 0) ||
-     (connection_write_to_buf(the_directory, directorylen, conn) < 0)) {
-    log_fn(LOG_DEBUG,"my outbuf is full. Oops.");
-    return -1;
+  switch(connection_fetch_from_buf_http(conn, headers, sizeof(headers), body, sizeof(body))) {
+    case -1: /* overflow */
+      log_fn(LOG_DEBUG,"input too large. Failing.");
+      return -1;
+    case 0:
+      log_fn(LOG_DEBUG,"command not all here yet.");
+      return 0;
+    /* case 1, fall through */
   }
 
-  conn->state = DIR_CONN_STATE_WRITING;
-  return 0;
-}
+  log_fn(LOG_DEBUG,"headers '%s', body '%s'.",headers,body);
+  if(!strncasecmp(headers,"GET",3)) {
 
-static int directory_handle_reading(connection_t *conn) {
-  int amt;
-  char *headers;
+    directory_rebuild(); /* rebuild it now, iff it's dirty */
 
-  assert(conn && conn->type == CONN_TYPE_DIR);
+    if(directorylen == 0) {
+      log_fn(LOG_DEBUG,"My directory is empty. Closing.");
+      return -1;
+    }
 
-  if(reading_headers) {
-    amt = connection_find_on_inbuf("\r\n\r\n", 4, conn);
-    if(amt < 0) /* not there yet */
-      return 0;
-    headers = tor_malloc(amt+1);
-    connection_fetch_from_buf(headers,amt,conn);
-    headers[amt] = 0; /* null terminate it, */
-    free(headers); /* and then throw it away */
-    reading_headers = 0;
+    log_fn(LOG_DEBUG,"Dumping directory to client."); 
+    if((connection_write_to_buf(answerstring, strlen(answerstring), conn) < 0) ||
+       (connection_write_to_buf(the_directory, directorylen, conn) < 0)) {
+      log_fn(LOG_DEBUG,"Failed to write answerstring+directory to outbuf.");
+      return -1;
+    }
+    conn->state = DIR_CONN_STATE_SERVER_WRITING;
+    return 0;
   }
 
-  amt = conn->inbuf_datalen;
-
-  if(amt + directorylen >= MAX_DIR_SIZE) {
-    log_fn(LOG_DEBUG,"Directory too large. Failing messily.");
-    return -1;
+  if(!strncasecmp(headers,"POST",4)) {
+    log_fn(LOG_DEBUG,"Received POST command, body '%s'", body);
+    if(connection_write_to_buf(answerstring, strlen(answerstring), conn) < 0) {
+      log_fn(LOG_DEBUG,"Failed to write answerstring to outbuf.");
+      return -1;
+    }
+    conn->state = DIR_CONN_STATE_SERVER_WRITING;
+    return 0;
   }
 
-  log_fn(LOG_DEBUG,"Pulling %d bytes in at offset %d.",
-    amt, directorylen);
-
-  connection_fetch_from_buf(the_directory+directorylen,amt,conn);
-
-  directorylen += amt;
-
-  the_directory[directorylen] = 0;
-
-  return 0;
+  log_fn(LOG_DEBUG,"Got headers with unknown command. Closing.");
+  return -1;
 }
 
 int connection_dir_finished_flushing(connection_t *conn) {
@@ -233,7 +241,8 @@ int connection_dir_finished_flushing(connection_t *conn) {
   assert(conn && conn->type == CONN_TYPE_DIR);
 
   switch(conn->state) {
-    case DIR_CONN_STATE_CONNECTING:
+    case DIR_CONN_STATE_CONNECTING_GET:
+    case DIR_CONN_STATE_CONNECTING_POST:
       if (getsockopt(conn->s, SOL_SOCKET, SO_ERROR, (void*)&e, &len) < 0)  { /* not yet */
         if(!ERRNO_CONN_EINPROGRESS(errno)) {
           log_fn(LOG_DEBUG,"in-progress connect failed. Removing.");
@@ -248,16 +257,19 @@ int connection_dir_finished_flushing(connection_t *conn) {
       log_fn(LOG_DEBUG,"Dir connection to router %s:%u established.",
           conn->address,conn->port);
 
-      return directory_send_command(conn);
-    case DIR_CONN_STATE_SENDING_COMMAND:
-      log_fn(LOG_DEBUG,"client finished sending command.");
-      directorylen = 0;
-      reading_headers = 1;
-      conn->state = DIR_CONN_STATE_READING;
+      return directory_send_command(conn, conn->state);
+    case DIR_CONN_STATE_CLIENT_SENDING_GET:
+      log_fn(LOG_DEBUG,"client finished sending 'get' command.");
+      conn->state = DIR_CONN_STATE_CLIENT_READING_GET;
+      connection_watch_events(conn, POLLIN);
+      return 0;
+    case DIR_CONN_STATE_CLIENT_SENDING_POST:
+      log_fn(LOG_DEBUG,"client finished sending 'post' command.");
+      conn->state = DIR_CONN_STATE_CLIENT_READING_POST;
       connection_watch_events(conn, POLLIN);
       return 0;
-    case DIR_CONN_STATE_WRITING:
-      log_fn(LOG_DEBUG,"Finished writing directory. Closing.");
+    case DIR_CONN_STATE_SERVER_WRITING:
+      log_fn(LOG_DEBUG,"Finished writing server response. Closing.");
       return -1; /* kill it */
     default:
       log_fn(LOG_DEBUG,"BUG: called in unexpected state.");

src/or/main.c

@@ -335,7 +335,7 @@ static int prepare_for_poll(void) {
         /* NOTE directory servers do not currently fetch directories.
          * Hope this doesn't bite us later.
          */
-        directory_initiate_fetch(router_pick_directory_server());
+        directory_initiate_command(router_pick_directory_server(), DIR_CONN_STATE_CONNECTING_GET);
         time_to_fetch_directory = now.tv_sec + options.DirFetchPeriod;
       }
     }
@@ -492,7 +492,7 @@ static int do_main_loop(void) {
           log(LOG_ERR,"Error reloading router list. Continuing with old list.");
         }
       } else {
-        directory_initiate_fetch(router_pick_directory_server());
+        directory_initiate_command(router_pick_directory_server(), DIR_CONN_STATE_CONNECTING_GET);
       }
       please_fetch_directory = 0;
     }
@@ -772,6 +772,10 @@ dump_signed_directory_to_string_impl(char *s, int maxlen, directory_t *dir,
   return 0;
 }
 
+char *router_get_my_descriptor(void) {
+  return "this is bob's descriptor";
+}
+
 void daemonize(void) {
 #ifndef MS_WINDOWS
   /* Fork; parent exits. */

src/or/or.h

@@ -156,12 +156,15 @@
 #define _AP_CONN_STATE_MAX 5
 
 #define _DIR_CONN_STATE_MIN 0
-#define DIR_CONN_STATE_CONNECTING 0 /* client */
-#define DIR_CONN_STATE_SENDING_COMMAND 1 /* client */
-#define DIR_CONN_STATE_READING 2 /* client */
-#define DIR_CONN_STATE_COMMAND_WAIT 3 /* dirserver */
-#define DIR_CONN_STATE_WRITING 4 /* dirserver */
-#define _DIR_CONN_STATE_MAX 4
+#define DIR_CONN_STATE_CONNECTING_GET 0
+#define DIR_CONN_STATE_CONNECTING_POST 1
+#define DIR_CONN_STATE_CLIENT_SENDING_GET 2
+#define DIR_CONN_STATE_CLIENT_SENDING_POST 3
+#define DIR_CONN_STATE_CLIENT_READING_GET 4
+#define DIR_CONN_STATE_CLIENT_READING_POST 5
+#define DIR_CONN_STATE_SERVER_COMMAND_WAIT 6
+#define DIR_CONN_STATE_SERVER_WRITING 7
+#define _DIR_CONN_STATE_MAX 7
 
 #define CIRCUIT_STATE_BUILDING 0 /* I'm the OP, still haven't done all my handshakes */
 #define CIRCUIT_STATE_ONIONSKIN_PENDING 1 /* waiting to process the onionskin */
@@ -437,6 +440,9 @@ int flush_buf_tls(tor_tls *tls, char **buf, int *buflen, int *buf_flushlen, int
 
 int write_to_buf(char *string, int string_len, char **buf, int *buflen, int *buf_datalen);
 int fetch_from_buf(char *string, int string_len, char **buf, int *buflen, int *buf_datalen);
+int fetch_from_buf_http(char *buf, int *buf_datalen,
+                        char *headers_out, int max_headerlen,
+                        char *body_out, int max_bodylen);
 int find_on_inbuf(char *string, int string_len, char *buf, int buf_datalen);
 
 /********************************* circuit.c ***************************/
@@ -504,6 +510,9 @@ int connection_handle_read(connection_t *conn);
 int connection_read_to_buf(connection_t *conn);
 
 int connection_fetch_from_buf(char *string, int len, connection_t *conn);
+int connection_fetch_from_buf_http(connection_t *conn,
+                                   char *headers_out, int max_headerlen,
+                                   char *body_out, int max_bodylen);
 int connection_find_on_inbuf(char *string, int len, connection_t *conn);
 
 int connection_wants_to_flush(connection_t *conn);
@@ -559,7 +568,7 @@ int assign_to_cpuworker(connection_t *cpuworker, unsigned char question_type,
 
 /********************************* directory.c ***************************/
 
-void directory_initiate_fetch(routerinfo_t *router);
+void directory_initiate_command(routerinfo_t *router, int command);
 void directory_set_dirty(void);
 int connection_dir_process_inbuf(connection_t *conn);
 int connection_dir_finished_flushing(connection_t *conn);
@@ -602,6 +611,7 @@ int dump_signed_directory_to_string(char *s, int maxlen,
 int dump_signed_directory_to_string_impl(char *s, int maxlen, 
                                          directory_t *dir, 
                                          crypto_pk_env_t *private_key); 
+char *router_get_my_descriptor(void);
 
 int main(int argc, char *argv[]);
 

src/or/routers.c

@@ -42,7 +42,16 @@ router_resolve_directory(directory_t *dir);
 int learn_my_address(struct sockaddr_in *me) {
   /* local host information */
   char localhostname[512];
-  struct hostent *localhost;
+  static struct hostent *localhost;
+  static int already_learned=0;
+
+  if(already_learned) {
+    memset(me,0,sizeof(struct sockaddr_in));
+    me->sin_family = AF_INET;
+    memcpy((void *)&me->sin_addr,(void *)localhost->h_addr,sizeof(struct in_addr));
+    me->sin_port = htons((uint16_t) options.ORPort);
+    return 0;
+  }
 
   /* obtain local host information */
   if(gethostname(localhostname,512) < 0) {
@@ -65,6 +74,7 @@ int learn_my_address(struct sockaddr_in *me) {
     /* We're a loopback IP but we're not called localhost.  Uh oh! */
     log_fn(LOG_WARNING, "Got a loopback address: /etc/hosts may be wrong");
   }
+  already_learned=1;
   return 0;
 }
 
@@ -977,7 +987,6 @@ int router_compare_to_exit_policy(connection_t *conn) {
   }
 
   return 0; /* accept all by default. */
-
 }
 
 /*