From: Matt Caswell <matt@openssl.org>
Date: Thu, 13 Aug 2015 09:06:30 +0000 (+0100)
Subject: Fix DTLS session ticket renewal
X-Git-Tag: OpenSSL_1_1_0-pre1~784
X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff_plain;h=ee4ffd6fccd169775ba74afb1dbfecff48ee413d;hp=d6dfa55038fdb948cb214adf634f379eeb859f5d

Fix DTLS session ticket renewal

A DTLS client will abort a handshake if the server attempts to renew the
session ticket. This is caused by a state machine discrepancy between DTLS
and TLS discovered during the state machine rewrite work.

The bug can be demonstrated as follows:

Start a DTLS s_server instance:
openssl s_server -dtls

Start a client and obtain a session but no ticket:
openssl s_client -dtls -sess_out session.pem -no_ticket

Now start a client reusing the session, but allow a ticket:
openssl s_client -dtls -sess_in session.pem

The client will abort the handshake.

Reviewed-by: Tim Hudson <tjh@openssl.org>
---

diff --git a/ssl/d1_clnt.c b/ssl/d1_clnt.c
index d4116147b4..083333eedb 100644
--- a/ssl/d1_clnt.c
+++ b/ssl/d1_clnt.c
@@ -380,6 +380,10 @@ int dtls1_connect(SSL *s)
 #endif
 
                     s->state = SSL3_ST_CR_CHANGE_A;
+                    if (s->tlsext_ticket_expected) {
+                        /* receive renewed session ticket */
+                        s->state = SSL3_ST_CR_SESSION_TICKET_A;
+                    }
                 } else
                     s->state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
             }