Big bridge bugfixes. Backport candidates.

If you have more than one bridge but don't know their keys,
you would only learn a request for the descriptor of the first one
on your list. (Tor considered launching requests for the others, but
found that it already had a connection on the way for $0000...0000
so it didn't open another.)
If you have more than one bridge but don't know their keys, and the
connection to one of the bridges failed, you would cancel all
pending bridge connections. (After all, they all have the same
digest.)


svn:r15366

1 files changed, 14 insertions, 5 deletions

diff --git a/src/or/circuituse.c b/src/or/circuituse.c
index 11bafda002..3ba548e6fb 100644
--- a/src/or/circuituse.c
+++ b/src/or/circuituse.c
@@ -95,10 +95,19 @@ circuit_is_acceptable(circuit_t *circ, edge_connection_t *conn,
       tor_assert(conn->chosen_exit_name);
       if (build_state->chosen_exit) {
         char digest[DIGEST_LEN];
-        if (hexdigest_to_digest(conn->chosen_exit_name, digest) < 0 ||
-            memcmp(digest, build_state->chosen_exit->identity_digest,
-                   DIGEST_LEN))
+        if (hexdigest_to_digest(conn->chosen_exit_name, digest) < 0)
+          return 0; /* broken digest, we don't want it */
+        if (memcmp(digest, build_state->chosen_exit->identity_digest,
+                          DIGEST_LEN))
           return 0; /* this is a circuit to somewhere else */
+        if (tor_digest_is_zero(digest)) {
+          /* we don't know the digest; have to compare addr:port */
+          struct in_addr in;
+          if (!tor_inet_aton(conn->socks_request->address, &in) ||
+              build_state->chosen_exit->addr != ntohl(in.s_addr) ||
+              build_state->chosen_exit->port != conn->socks_request->port)
+            return 0;
+        }
       }
     } else {
       if (conn->want_onehop) {
@@ -749,7 +758,7 @@ circuit_build_failed(origin_circuit_t *circ)
     }
     /* if there are any one-hop streams waiting on this circuit, fail
      * them now so they can retry elsewhere. */
-    connection_ap_fail_onehop(circ->_base.n_conn_id_digest);
+    connection_ap_fail_onehop(circ->_base.n_conn_id_digest, circ->build_state);
   }
 
   switch (circ->_base.purpose) {
@@ -1330,7 +1339,7 @@ connection_ap_handshake_attach_circuit(edge_connection_t *conn)
     /* find the circuit that we should use, if there is one. */
     retval = circuit_get_open_circ_or_launch(
         conn, CIRCUIT_PURPOSE_C_GENERAL, &circ);
-    if (retval < 1)
+    if (retval < 1) // XXX021 if we totally fail, this still returns 0 -RD
       return retval;
 
     log_debug(LD_APP|LD_CIRC,