From 8c2b1d872b25f3ec78e04f5cd2de8f21e853c4a6 Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Fri, 29 May 2015 17:05:01 +0100 Subject: [PATCH] Check the message type requested is the type received in DTLS dtls1_get_message has an |mt| variable which is the type of the message that is being requested. If it is negative then any message type is allowed. However the value of |mt| is not checked in one of the main code paths, so a peer can send a message of a completely different type and it will be processed as if it was the message type that we were expecting. This has very little practical consequences because the current behaviour will still fail when the format of the message isn't as expected. Reviewed-by: Andy Polyakov --- ssl/d1_both.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/ssl/d1_both.c b/ssl/d1_both.c index bcdba74819..569b561e85 100644 --- a/ssl/d1_both.c +++ b/ssl/d1_both.c @@ -478,6 +478,12 @@ long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) return i; } + if (mt >= 0 && s->s3->tmp.message_type != mt) { + al = SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_DTLS1_GET_MESSAGE, SSL_R_UNEXPECTED_MESSAGE); + goto f_err; + } + p = (unsigned char *)s->init_buf->data; msg_len = msg_hdr->msg_len; -- 2.25.1