From: Guus Sliepen <guus@tinc-vpn.org>
Date: Sun, 18 Mar 2012 16:46:30 +0000 (+0100)
Subject: Don't send an ACK message after the first key exchange in the SPTPS protocol.
X-Git-Tag: import-tinc-1.1~388
X-Git-Url: http://git.meshlink.io/?p=meshlink;a=commitdiff_plain;h=d756bb92ed52d5b1ecdd42af32f11f733db64d91

Don't send an ACK message after the first key exchange in the SPTPS protocol.
---

diff --git a/src/sptps.c b/src/sptps.c
index fa1594db..2449e7bc 100644
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -301,7 +301,7 @@ static bool receive_sig(sptps_t *s, const char *data, uint16_t len) {
 	s->hiskex = NULL;
 
 	// Send cipher change record
-	if(!send_ack(s))
+	if(s->outstate && !send_ack(s))
 		return false;
 
 	// TODO: only set new keys after ACK has been set/received
@@ -319,8 +319,6 @@ static bool receive_sig(sptps_t *s, const char *data, uint16_t len) {
 			return false;
 	}
 
-	s->outstate = true;
-
 	return true;
 }
 
@@ -352,7 +350,16 @@ static bool receive_handshake(sptps_t *s, const char *data, uint16_t len) {
 			// If we already sent our secondary public ECDH key, we expect the peer to send his.
 			if(!receive_sig(s, data, len))
 				return false;
-			s->state = SPTPS_ACK;
+			if(s->outstate)
+				s->state = SPTPS_ACK;
+			else {
+				s->outstate = true;
+				if(!receive_ack(s, NULL, 0))
+					return false;
+				s->receive_record(s->handle, SPTPS_HANDSHAKE, NULL, 0);
+				s->state = SPTPS_SECONDARY_KEX;
+			}
+
 			return true;
 		case SPTPS_ACK:
 			// We expect a handshake message to indicate transition to the new keys.