Avoid double free when processing DTLS packets.

The |item| variable, in both of these cases, may contain a pointer to a
|pitem| structure within |s->d1->buffered_messages|. It was being freed
in the error case while still being in |buffered_messages|. When the
error later caused the |SSL*| to be destroyed, the item would be double
freed.

Thanks to Wah-Teh Chang for spotting that the fix in 1632ef74 was
inconsistent with the other error paths (but correct).

Fixes CVE-2014-3505

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Added comment for the frag->reassembly == NULL case as per feedback from Emilia

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Fix DTLS handshake message size checks.

In |dtls1_reassemble_fragment|, the value of
|msg_hdr->frag_off+frag_len| was being checked against the maximum
handshake message size, but then |msg_len| bytes were allocated for the
fragment buffer. This means that so long as the fragment was within the
allowed size, the pending handshake message could consume 16MB + 2MB
(for the reassembly bitmap). Approx 10 outstanding handshake messages
are allowed, meaning that an attacker could consume ~180MB per DTLS
connection.

In the non-fragmented path (in |dtls1_process_out_of_seq_message|), no
check was applied.

Fixes CVE-2014-3506

Wholly based on patch by Adam Langley with one minor amendment.

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Fix memory leak from zero-length DTLS fragments.

The |pqueue_insert| function can fail if one attempts to insert a
duplicate sequence number. When handling a fragment of an out of
sequence message, |dtls1_process_out_of_seq_message| would not call
|dtls1_reassemble_fragment| if the fragment's length was zero. It would
then allocate a fresh fragment and attempt to insert it, but ignore the
return value, leaking the fragment.

This allows an attacker to exhaust the memory of a DTLS peer.

Fixes CVE-2014-3507

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Fix return code for truncated DTLS fragment.

Previously, a truncated DTLS fragment in
|dtls1_process_out_of_seq_message| would cause *ok to be cleared, but
the return value would still be the number of bytes read. This would
cause |dtls1_get_message| not to consider it an error and it would
continue processing as normal until the calling function noticed that
*ok was zero.

I can't see an exploit here because |dtls1_get_message| uses
|s->init_num| as the length, which will always be zero from what I can
see.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Applying same fix as in dtls1_process_out_of_seq_message. A truncated DTLS fragment would cause *ok to be clear, but the return value would still be the number of bytes read.

Problem identified by Emilia Käsper, based on previous issue/patch by Adam
Langley.

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Remove some duplicate DTLS code.

In a couple of functions, a sequence number would be calculated twice.

Additionally, in |dtls1_process_out_of_seq_message|, we know that
|frag_len| <= |msg_hdr->msg_len| so the later tests for |frag_len <
msg_hdr->msg_len| can be more clearly written as |frag_len !=
msg_hdr->msg_len|, since that's the only remaining case.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Fix protocol downgrade bug in case of fragmented packets

CVE-2014-3511

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Bodo Möller <bodo@openssl.org>
Fix DTLS anonymous EC(DH) denial of service

CVE-2014-3510

Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Fix OID handling:

- Upon parsing, reject OIDs with invalid base-128 encoding.
- Always NUL-terminate the destination buffer in OBJ_obj2txt printing function.

CVE-2014-3508

Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Fix race condition in ssl_parse_serverhello_tlsext

CVE-2014-3509
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Fix SRP ciphersuite DoS vulnerability.

If a client attempted to use an SRP ciphersuite and it had not been
set up correctly it would crash with a null pointer read. A malicious
server could exploit this in a DoS attack.

Thanks to Joonas Kuorilehto and Riku Hietamäki from Codenomicon
for reporting this issue.

CVE-2014-2970
Reviewed-by: Tim Hudson <tjh@openssl.org>
Fix SRP buffer overrun vulnerability.

Invalid parameters passed to the SRP code can be overrun an internal
buffer. Add sanity check that g, A, B < N to SRP code.

Thanks to Sean Devlin and Watson Ladd of Cryptography Services, NCC
Group for reporting this issue.
Check SRP parameters early.

Check SRP parameters when they are received so we can send back an
appropriate alert.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>