Duplicate identities now checked with zmq_connect

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

1 files changed, 43 insertions, 2 deletions

diff --git a/src/connect_session.cpp b/src/connect_session.cpp
index 0df9854..c0951cb 100644
--- a/src/connect_session.cpp
+++ b/src/connect_session.cpp
@@ -28,12 +28,15 @@ zmq::connect_session_t::connect_session_t (class io_thread_t *io_thread_,
       const char *protocol_, const char *address_) :
     session_t (io_thread_, socket_, options_),
     protocol (protocol_),
-    address (address_)
+    address (address_),
+    connected (false)
 {
 }
 
 zmq::connect_session_t::~connect_session_t ()
 {
+    if (connected && !peer_identity.empty ())
+        unregister_session (peer_identity);
 }
 
 void zmq::connect_session_t::process_plug ()
@@ -107,8 +110,46 @@ void zmq::connect_session_t::start_connecting (bool wait_)
     zmq_assert (false);
 }
 
-void zmq::connect_session_t::attached (const blob_t &peer_identity_)
+bool zmq::connect_session_t::attached (const blob_t &peer_identity_)
 {
+    //  If there was no previous connection...
+    if (!connected) {
+
+        //  Peer has transient identity.
+        if (peer_identity_.empty () || peer_identity_ [0] == 0) {
+            connected = true;
+            return true;
+        }
+
+        //  Peer has strong identity. Let's register it and check whether noone
+        //  else is using the same identity.
+        if (!register_session (peer_identity_, this)) {
+            log ("DPID: duplicate peer identity - disconnecting peer");
+            return false;
+        }
+        connected = true;
+        peer_identity = peer_identity_;
+        return true;
+    }
+
+    //  New engine from listener can conflict with existing engine.
+    //  Alternatively, new engine created by reconnection process can
+    //  conflict with engine supplied by listener in the meantime.
+    if (has_engine ()) {
+        log ("DPID: duplicate peer identity - disconnecting peer");
+        return false;
+    }
+
+    //  If there have been a connection before, we have to check whether
+    //  peer's identity haven't changed in the meantime.
+    if ((peer_identity_.empty () || peer_identity_ [0] == 0) &&
+          peer_identity.empty ())
+        return true;
+    if (peer_identity != peer_identity_) {
+        log ("CHID: peer have changed identity - disconnecting peer");
+        return false;
+    }
+    return true;
 }
 
 void zmq::connect_session_t::detached ()