Send NETINFO on receiving a NETINFO if we have not yet sent one.

Relays previously, when initiating a connection, would only send a
NETINFO after sending an AUTHENTICATE.  But bridges, when receiving a
connection, would never send AUTH_CHALLENGE.  So relays wouldn't
AUTHENTICATE, and wouldn't NETINFO, and then bridges would be
surprised to be receiving CREATE cells on a non-open circuit.

Fixes bug 9546.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/or/connection_or.c b/src/or/connection_or.c
index 3616363505..31cc9c78d8 100644
--- a/src/or/connection_or.c
+++ b/src/or/connection_or.c
@@ -2042,6 +2042,12 @@ connection_or_send_netinfo(or_connection_t *conn)
 
   tor_assert(conn->handshake_state);
 
+  if (conn->handshake_state->sent_netinfo) {
+    log_warn(LD_BUG, "Attempted to send an extra netinfo cell on a connection "
+             "where we already sent one.");
+    return 0;
+  }
+
   memset(&cell, 0, sizeof(cell_t));
   cell.command = CELL_NETINFO;
 
@@ -2083,6 +2089,7 @@ connection_or_send_netinfo(or_connection_t *conn)
   }
 
   conn->handshake_state->digest_sent_data = 0;
+  conn->handshake_state->sent_netinfo = 1;
   connection_or_write_cell_to_buf(&cell, conn);
 
   return 0;