PORTREVISION=	1

commit 3fbc7cd331602c76f882d1b507cd05c1d824ba8b

Author: Matthias Andree <matthias.andree@gmx.de>

Date:   Mon Aug 13 20:48:12 2012 +0200

    Fix crash: Handle invalid base64 in NTLM challenge.

    Some servers, for instance the MS Exchange servers deployed by the

    US-American National Aeronautics and Space Administration (NASA),

    aborted the NTLM protocol exchange after receiving the initial request.

    Fetchmail did not detect that there was an error message, rather than

    NTLM protocol exchange, and caught a segmentation fault while reading

    from a bad location.

    Detect base64 decoding errors, and return PS_AUTHFAIL in this case.

    Reported by J[ames] Porter Clark.

diff --git a/ntlmsubr.c b/ntlmsubr.c

index f9d2733..9321d26 100644

--- a/ntlmsubr.c

+++ b/ntlmsubr.c

@@ -55,7 +55,14 @@ int ntlm_helper(int sock, struct query *ctl, const char *proto)

     if ((result = gen_recv(sock, msgbuf, sizeof msgbuf)))

 	goto cancelfail;

-    (void)from64tobits (&challenge, msgbuf, sizeof(challenge));

+    if ((result = from64tobits (&challenge, msgbuf, sizeof(challenge))) < 0)

+    {

+	report (stderr, GT_("could not decode BASE64 challenge\n"));

+	/* We do not goto cancelfail; the server has already sent the

+	 * tagged reply, so the protocol exchange has ended, no need

+	 * for us to send the asterisk. */

+	return PS_AUTHFAIL;

+    }

     if (outlevel >= O_DEBUG)

 	dumpSmbNtlmAuthChallenge(stdout, &challenge);