Use the new guard notification/selection APIs throughout Tor

This patch doesn't cover every case; omitted cases are marked with
"XXXX prop271", as usual.  It leaves both the old interface and the
new interface for guard status notification, since they don't
actually work in the same way: the new API wants to be told when a
circuit has failed or succeeded, whereas the old API wants to know
when a channel has failed or succeeded.

I ran into some trouble with directory guard stuff, since when we
pick the directory guard, we don't actually have a circuit to
associate it with.  I solved that by allowing guard states to be
associated with directory connections, not just circuits.

1 files changed, 60 insertions, 14 deletions

diff --git a/src/or/directory.c b/src/or/directory.c
index efa5a3126a..4164672f10 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -128,7 +128,8 @@ static void directory_initiate_command_rend(
                                           const char *payload,
                                           size_t payload_len,
                                           time_t if_modified_since,
-                                          const rend_data_t *rend_query);
+                                          const rend_data_t *rend_query,
+                                          circuit_guard_state_t *guard_state);
 
 static void connection_dir_close_consensus_fetches(
                    dir_connection_t *except_this_one, const char *resource);
@@ -422,7 +423,8 @@ directory_post_to_dirservers(uint8_t dir_purpose, uint8_t router_purpose,
       directory_initiate_command_routerstatus(rs, dir_purpose,
                                               router_purpose,
                                               indirection,
-                                              NULL, payload, upload_len, 0);
+                                              NULL, payload, upload_len, 0,
+                                              NULL);
   } SMARTLIST_FOREACH_END(ds);
   if (!found) {
     char *s = authdir_type_to_string(type);
@@ -458,7 +460,8 @@ should_use_directory_guards(const or_options_t *options)
  * information of type <b>type</b>, and return its routerstatus. */
 static const routerstatus_t *
 directory_pick_generic_dirserver(dirinfo_type_t type, int pds_flags,
-                                 uint8_t dir_purpose)
+                                 uint8_t dir_purpose,
+                                 circuit_guard_state_t **guard_state_out)
 {
   const routerstatus_t *rs = NULL;
   const or_options_t *options = get_options();
@@ -467,7 +470,7 @@ directory_pick_generic_dirserver(dirinfo_type_t type, int pds_flags,
     log_warn(LD_BUG, "Called when we have UseBridges set.");
 
   if (should_use_directory_guards(options)) {
-    const node_t *node = choose_random_dirguard(type);
+    const node_t *node = guards_choose_dirguard(type, guard_state_out);
     if (node)
       rs = node->rs;
   } else {
@@ -548,6 +551,7 @@ MOCK_IMPL(void, directory_get_from_dirserver, (
   if (!options->FetchServerDescriptors)
     return;
 
+  circuit_guard_state_t *guard_state = NULL;
   if (!get_via_tor) {
     if (options->UseBridges && !(type & BRIDGE_DIRINFO)) {
       /* We want to ask a running bridge for which we have a descriptor.
@@ -556,6 +560,7 @@ MOCK_IMPL(void, directory_get_from_dirserver, (
        * sort of dir fetch we'll be doing, so it won't return a bridge
        * that can't answer our question.
        */
+      // XXXX prop271 update this for bridge support.
       const node_t *node = choose_random_dirguard(type);
       if (node && node->ri) {
         /* every bridge has a routerinfo. */
@@ -605,9 +610,9 @@ MOCK_IMPL(void, directory_get_from_dirserver, (
         }
       }
       if (!rs && !(type & BRIDGE_DIRINFO)) {
-        /* */
         rs = directory_pick_generic_dirserver(type, pds_flags,
-                                              dir_purpose);
+                                              dir_purpose,
+                                              &guard_state);
         if (!rs)
           get_via_tor = 1; /* last resort: try routing it via Tor */
       }
@@ -630,7 +635,8 @@ MOCK_IMPL(void, directory_get_from_dirserver, (
                                             router_purpose,
                                             indirection,
                                             resource, NULL, 0,
-                                            if_modified_since);
+                                            if_modified_since,
+                                            guard_state);
   } else {
     log_notice(LD_DIR,
                "While fetching directory info, "
@@ -664,7 +670,7 @@ directory_get_from_all_authorities(uint8_t dir_purpose,
       rs = &ds->fake_status;
       directory_initiate_command_routerstatus(rs, dir_purpose, router_purpose,
                                               DIRIND_ONEHOP, resource, NULL,
-                                              0, 0);
+                                              0, 0, NULL);
   } SMARTLIST_FOREACH_END(ds);
 }
 
@@ -775,7 +781,8 @@ directory_initiate_command_routerstatus_rend(const routerstatus_t *status,
                                              const char *payload,
                                              size_t payload_len,
                                              time_t if_modified_since,
-                                             const rend_data_t *rend_query)
+                                             const rend_data_t *rend_query,
+                                           circuit_guard_state_t *guard_state)
 {
   const or_options_t *options = get_options();
   const node_t *node;
@@ -830,7 +837,8 @@ directory_initiate_command_routerstatus_rend(const routerstatus_t *status,
                                   dir_purpose, router_purpose,
                                   indirection, resource,
                                   payload, payload_len, if_modified_since,
-                                  rend_query);
+                                  rend_query,
+                                  guard_state);
 }
 
 /** Launch a new connection to the directory server <b>status</b> to
@@ -855,13 +863,15 @@ MOCK_IMPL(void, directory_initiate_command_routerstatus,
                  const char *resource,
                  const char *payload,
                  size_t payload_len,
-                 time_t if_modified_since))
+                 time_t if_modified_since,
+                 circuit_guard_state_t *guard_state))
 {
   directory_initiate_command_routerstatus_rend(status, dir_purpose,
                                           router_purpose,
                                           indirection, resource,
                                           payload, payload_len,
-                                          if_modified_since, NULL);
+                                          if_modified_since, NULL,
+                                          guard_state);
 }
 
 /** Return true iff <b>conn</b> is the client side of a directory connection
@@ -889,6 +899,11 @@ directory_conn_is_self_reachability_test(dir_connection_t *conn)
 static void
 connection_dir_request_failed(dir_connection_t *conn)
 {
+  if (conn->guard_state) {
+    /* We haven't seen a success on this guard state, so consider it to have
+     * failed. */
+    entry_guard_failed(get_guard_selection_info(), &conn->guard_state);
+  }
   if (directory_conn_is_self_reachability_test(conn)) {
     return; /* this was a test fetch. don't retry. */
   }
@@ -1136,7 +1151,7 @@ directory_initiate_command(const tor_addr_t *or_addr, uint16_t or_port,
                              digest, dir_purpose,
                              router_purpose, indirection,
                              resource, payload, payload_len,
-                             if_modified_since, NULL);
+                             if_modified_since, NULL, NULL);
 }
 
 /** Same as directory_initiate_command(), but accepts rendezvous data to
@@ -1151,7 +1166,8 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port,
                                 const char *resource,
                                 const char *payload, size_t payload_len,
                                 time_t if_modified_since,
-                                const rend_data_t *rend_query)
+                                const rend_data_t *rend_query,
+                                circuit_guard_state_t *guard_state)
 {
   tor_assert(or_addr_port);
   tor_assert(dir_addr_port);
@@ -1246,12 +1262,18 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port,
 
   if (!anonymized_connection && !use_begindir) {
     /* then we want to connect to dirport directly */
+    // XXXX prop271 I think that we never use guards in this case.
 
     if (options->HTTPProxy) {
       tor_addr_copy(&addr, &options->HTTPProxyAddr);
       port = options->HTTPProxyPort;
     }
 
+    // In this case we should not have picked a directory guard.
+    if (BUG(guard_state)) {
+      entry_guard_cancel(get_guard_selection_info(), &guard_state);
+    }
+
     switch (connection_connect(TO_CONN(conn), conn->base_.address, &addr,
                                port, &socket_error)) {
       case -1:
@@ -1288,6 +1310,14 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port,
     else if (anonymized_connection && !use_begindir)
       rep_hist_note_used_port(time(NULL), conn->base_.port);
 
+    // In this case we should not have a directory guard; we'll
+    // get a regular guard later when we build the circuit.
+    if (BUG(anonymized_connection && guard_state)) {
+      entry_guard_cancel(get_guard_selection_info(), &guard_state);
+    }
+
+    conn->guard_state = guard_state;
+
     /* make an AP connection
      * populate it and add it at the right state
      * hook up both sides
@@ -2540,6 +2570,22 @@ connection_dir_process_inbuf(dir_connection_t *conn)
   tor_assert(conn);
   tor_assert(conn->base_.type == CONN_TYPE_DIR);
 
+  if (conn->guard_state) {
+    /* we count the connection as successful once we can read from it.  We do
+     * not, however, delay use of the circuit here, since it's just for a
+     * one-hop directory request. */
+    /* XXXXprop271 note that this will not do the right thing for other
+     * waiting circuits that would be triggered by this circuit becoming
+     * complete/usable. But that's ok, I think.
+     */
+    /* XXXXprop271 should we count this as only a partial success somehow?
+    */
+    entry_guard_succeeded(get_guard_selection_info(),
+                          &conn->guard_state);
+    circuit_guard_state_free(conn->guard_state);
+    conn->guard_state = NULL;
+  }
+
   /* Directory clients write, then read data until they receive EOF;
    * directory servers read data until they get an HTTP command, then
    * write their response (when it's finished flushing, they mark for