commit 4c00df9463ea4fd70b73c620e439f5c3ee5efa60
Author: Mike Gelfand <mikedld@mikedld.com>
Date:   Sun Sep 18 13:58:15 2016 +0300

    Abort handshake if establishing DH shared secret fails
    
    Fixes #27

diff --git a/libtransmission/handshake.c b/libtransmission/handshake.c
index c728696..e7ff131 100644
--- a/libtransmission/handshake.c
+++ b/libtransmission/handshake.c
@@ -425,7 +425,8 @@ readYb (tr_handshake * handshake, struct evbuffer * inbuf)
 
   /* compute the secret */
   evbuffer_remove (inbuf, yb, KEY_LEN);
-  tr_cryptoComputeSecret (handshake->crypto, yb);
+  if (!tr_cryptoComputeSecret (handshake->crypto, yb))
+    return tr_handshakeDone (handshake, false);
 
   /* now send these: HASH ('req1', S), HASH ('req2', SKEY) xor HASH ('req3', S),
    * ENCRYPT (VC, crypto_provide, len (PadC), PadC, len (IA)), ENCRYPT (IA) */
@@ -741,7 +742,9 @@ readYa (tr_handshake    * handshake,
 
   /* read the incoming peer's public key */
   evbuffer_remove (inbuf, ya, KEY_LEN);
-  tr_cryptoComputeSecret (handshake->crypto, ya);
+  if (!tr_cryptoComputeSecret (handshake->crypto, ya))
+    return tr_handshakeDone (handshake, false);
+
   computeRequestHash (handshake, "req1", handshake->myReq1);
 
   /* send our public key to the peer */