Clients avoid choosing nodes that can't do ntor

If we know a node's version, and it can't do ntor, consider it not running.
If we have a node's descriptor, and it doesn't have a valid ntor key,
consider it not running.

Refactor these checks so they're consistent between authorities and clients.

1 files changed, 4 insertions, 3 deletions

diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c
index 13cc16670c..d6c5c85f2c 100644
--- a/src/or/circuitbuild.c
+++ b/src/or/circuitbuild.c
@@ -820,8 +820,8 @@ circuit_pick_create_handshake(uint8_t *cell_type_out,
 
 /** Decide whether to use a TAP or ntor handshake for connecting to <b>ei</b>
  * directly, and set *<b>handshake_type_out</b> accordingly. Decide whether,
- * in extending through <b>node</b> to do so, we should use an EXTEND2 or an
- * EXTEND cell to do so, and set *<b>cell_type_out</b> and
+ * in extending through <b>node_prev</b> to do so, we should use an EXTEND2 or
+ * an EXTEND cell to do so, and set *<b>cell_type_out</b> and
  * *<b>create_cell_type_out</b> accordingly. */
 static void
 circuit_pick_extend_handshake(uint8_t *cell_type_out,
@@ -837,7 +837,8 @@ circuit_pick_extend_handshake(uint8_t *cell_type_out,
   if (node_prev &&
       *handshake_type_out != ONION_HANDSHAKE_TYPE_TAP &&
       (node_has_curve25519_onion_key(node_prev) ||
-       (node_prev->rs && node_prev->rs->version_supports_extend2_cells))) {
+       (node_prev->rs &&
+        routerstatus_version_supports_ntor(node_prev->rs, 0)))) {
     *cell_type_out = RELAY_COMMAND_EXTEND2;
     *create_cell_type_out = CELL_CREATE2;
   } else {