Turn them into static functions that take in an hm_fragment. It's not
immediately obvious that the frag_off/frag_len bounds checks and the msg_len
consistency check are critical to avoiding an out-of-bounds write. Better to
have dtls1_hm_fragment_mark also check internally.
Also rework the bitmask logic to be clearer and avoid a table.
Change-Id: Ica54e98f66295efb323e033cb6c67ab21e7d6cbc
Reviewed-on: https://boringssl-review.googlesource.com/3765
Reviewed-by: Adam Langley <agl@google.com>
Notably, drop all special cases around receiving a message in order and
receiving a full message. It makes things more complicated and was the source
of bugs (the MixCompleteMessageWithFragments tests added in this CL did not
pass before). Instead, every message goes through an hm_fragment, and
dtls1_get_message always checks buffered_messages to see if the next is
complete.
The downside is that we pay one more copy of the message data in the common
case. This is only during connection setup, so I think it's worth the
simplicity. (If we want to optimize later, we could either tighten
ssl3_get_message's interface to allow the handshake data being in the
hm_fragment's backing store rather than s->init_buf or swap out s->init_buf
with the hm_fragment's backing store when a mesasge completes.
This CL does not address ssl_read_bytes being an inappropriate API for DTLS.
Future work will revise the handshake/transport boundary to align better with
DTLS's needs. Also other problems that I've left as TODOs.
Change-Id: Ib4570d45634b5181ecf192894d735e8699b1c86b
Reviewed-on: https://boringssl-review.googlesource.com/3764
Reviewed-by: Adam Langley <agl@google.com>
We don't support DTLS renego. Removing this separately from the rewrite to call
out intentionally dropping this logic.
Change-Id: Ie4428eea0d2dbbb8b4b8b6474df4821de62558cc
Reviewed-on: https://boringssl-review.googlesource.com/3761
Reviewed-by: Adam Langley <agl@google.com>
That might be a reasonable check to make, maybe.
DTLS handshake message reading has a ton of other bugs and needs a complete
rewrite. But let's fix this and get a test in now.
Change-Id: I4981fc302feb9125908bb6161ed1a18288c39e2b
Reviewed-on: https://boringssl-review.googlesource.com/3600
Reviewed-by: Adam Langley <agl@google.com>
We can pass the fragment pointer to dtls1_retransmit_message rather than
having it look it up again.
Change-Id: If6957428418a44e7ceac91a93f7c6032d331d9d8
Reviewed-on: https://boringssl-review.googlesource.com/3510
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
It may fail because the BIO_write to the memory BIO can allocate.
Unfortunately, this bubbles up pretty far up now that we've moved the handshake
hash to ssl3_set_handshake_header.
Change-Id: I58884347a4456bb974ac4783078131522167e29d
Reviewed-on: https://boringssl-review.googlesource.com/3483
Reviewed-by: Adam Langley <agl@google.com>
SSL_AEAD_CTX ownership is currently too confusing. Instead, rely on the lack of
renego, so the previous epoch always uses the NULL cipher. (Were we to support
DTLS renego, we could keep track of s->d1->last_aead_write_ctx like
s->d1->last_write_sequence, but it isn't worth it.)
Buffered messages also tracked an old s->session, but this is unnecessary. The
s->session NULL check in tls1_enc dates to the OpenSSL initial commit and is
redundant with the aead NULL check.
Change-Id: I9a510468d95934c65bca4979094551c7536980ae
Reviewed-on: https://boringssl-review.googlesource.com/3234
Reviewed-by: Adam Langley <agl@google.com>
This is only applicable for renego and is wrong anyway. The handshake_read_seq
check doesn't account for message reordering. The correct check is if we
haven't yet processed the peer's CCS in the current handshake.
(The other Finished special-case needs to stay, however.)
Change-Id: Ic42897aab7140285ce2f3be24d52b81851b912b5
Reviewed-on: https://boringssl-review.googlesource.com/3231
Reviewed-by: Adam Langley <agl@google.com>
The existing comments are not very helpful. This code is also quite buggy.
Document two of them as TODOs.
Change-Id: Idfaf93d9c3b8b1ee92f2fb0d292ef513b5f6d824
Reviewed-on: https://boringssl-review.googlesource.com/2830
Reviewed-by: Adam Langley <agl@google.com>
BIO_ctrls do not have terribly well-defined return values on error. (Though the
existing ones seem to all return 0, not -1, on nonexistant operation.)
Change-Id: I08497f023ce3257c253aa71517a98b2fe73c3f74
Reviewed-on: https://boringssl-review.googlesource.com/2829
Reviewed-by: Adam Langley <agl@google.com>
g_probably_mtu and dtls1_guess_mtu is a bunch of logic for guessing the right
MTU, but it only ever returns the maximum (the input is always zero). Trim that
down to only what it actually does.
Change-Id: If3afe3f68ccb36cbf9c4525372564d16a4bbb73f
Reviewed-on: https://boringssl-review.googlesource.com/2828
Reviewed-by: Adam Langley <agl@google.com>
The retry doesn't actually work when we're sending a non-initial fragment; the
s->init_off != 0 block will get re-run each iteration through and continually
prepend headers. It can also infinite loop if the BIO reports
BIO_CTRL_DGRAM_MTU_EXCEEDED but either fails to report an MTU or reports an MTU
that always rounds up to the minimum. See upstream's
d3d9eef31661633f5b003a9e115c1822f79d1870.
WebRTC doesn't participate in any of the MTU logic and inherits the default
MTU, so just remove it for now.
Change-Id: Ib2ed2ba016b7c229811741fb7369c015ba0b551f
Reviewed-on: https://boringssl-review.googlesource.com/2827
Reviewed-by: Adam Langley <agl@google.com>
That setting means that the MTU is provided externally via SSL_set_mtu.
(Imported from upstream's 001235778a6e9c645dc0507cad6092d99c9af8f5)
Change-Id: I4e5743a9dee734ddd0235f080aefe98a7365aaf6
Reviewed-on: https://boringssl-review.googlesource.com/2826
Reviewed-by: Adam Langley <agl@google.com>
Based in part on upstream's cf75017bfd60333ff65edf9840001cd2c49870a3. This
situation really shouldn't be able to happen, but between no static asserts
that the minimum MTU is always large enough and a bug in reseting the MTU later
(to be fixed be a follow-up import from upstream), check these and return a
useful error code.
Change-Id: Ie853e5d35a6a7bc9c0032e74ae71529d490f4fe2
Reviewed-on: https://boringssl-review.googlesource.com/2825
Reviewed-by: Adam Langley <agl@google.com>
This CL removes the last of the EVP_CIPHER codepath in ssl/. The dead code is
intentionally not pruned for ease of review, except in DTLS-only code where
adding new logic to support both, only to remove half, would be cumbersome.
Fixes made:
- dtls1_retransmit_state is taught to retain aead_write_ctx rather than
enc_write_ctx.
- d1_pkt.c reserves space for the variable-length nonce when echoed into the
packet.
- dtls1_do_write sizes the MTU based on EVP_AEAD max overhead.
- tls1_change_cipher_state_cipher should not free AEAD write contexts in DTLS.
This matches the (rather confused) ownership for the EVP_CIPHER contexts.
I've added a TODO to resolve this craziness.
A follow-up CL will remove all the resultant dead code.
Change-Id: I644557f4db53bbfb182950823ab96d5e4c908866
Reviewed-on: https://boringssl-review.googlesource.com/2699
Reviewed-by: Adam Langley <agl@google.com>
This avoids needing a should_add_to_finished_hash boolean on do_write. The
logic in do_write was a little awkward because do_write would be called
multiple times if the write took several iterations. This also gets complex if
DTLS retransmits are involved. (At a glance, it's not obvious the
BIO_CTRL_DGRAM_MTU_EXCEEDED case actually works.)
Doing it as the handshake message is being prepared avoids this concern. It
also gives a natural point for the extended master secret logic which needs to
do work after the finished hash has been sampled.
As a bonus, we can remove s->d1->retransmitting which was only used to deal
with this issue.
Change-Id: Ifedf23ee4a6c5e08f960d296a6eb1f337a16dc7a
Reviewed-on: https://boringssl-review.googlesource.com/2604
Reviewed-by: Adam Langley <agl@google.com>
The frag_off/frag_len parameters are always zero, and the return value is never
used.
Change-Id: If7487b23c55f2a996e411b25b76a8e1651f25d8b
Reviewed-on: https://boringssl-review.googlesource.com/2601
Reviewed-by: Adam Langley <agl@google.com>
This change has no semantic effect (I hope!). It's just a reformatting
of a few files in ssl/. This is just a start – the other files in ssl/
should follow in the coming days.
Change-Id: I5eb3f4b18d0d46349d0f94d3fe5ab2003db5364e
This was added in http://rt.openssl.org/Ticket/Display.html?id=2033 to support
a mode where a DTLS socket would statelessly perform the ClientHello /
HelloVerifyRequest portion of the handshake, to be handed off to a socket
specific to this peer address.
This is not used by WebRTC or other current consumers. If we need to support
something like this, it would be cleaner to do the listen portion (cookieless
ClientHello + HelloVerifyRequest) externally and then spin up an SSL instance
on receipt of a cookied ClientHello. This would require a slightly more complex
BIO to replay the second ClientHello but would avoid peppering the DTLS
handshake state with a special short-circuiting mode.
Change-Id: I7a413932edfb62f8b9368912a9a0621d4155f1aa
Reviewed-on: https://boringssl-review.googlesource.com/2220
Reviewed-by: Adam Langley <agl@google.com>
This code isn't compiled in. It seems there was some half-baked logic for a
7-byte alert that includes more information about handshake messages
retransmit.
No such alert exists, and the code had a FIXME anyway. If it gets resurrected
in DTLS 1.3 or some extension, we can deal with it then.
Change-Id: I8784ea8ee44bb8da4b0fe5d5d507997526557432
Reviewed-on: https://boringssl-review.googlesource.com/2121
Reviewed-by: Adam Langley <agl@google.com>
Thanks to Denis Denisov for running the analysis.
Change-Id: I80810261e013423e746fd8d8afefb3581cffccc0
Reviewed-on: https://boringssl-review.googlesource.com/1701
Reviewed-by: Adam Langley <agl@google.com>
This replaces the special-case in ssl3_get_message for Channel ID. Also add
ssl3_hash_current_message to hash the current message, taking TLS vs DTLS
handshake header size into account.
One subtlety with this flag is that a message intended to be processed with
SSL_GET_MESSAGE_DONT_HASH_MESSAGE cannot follow an optional message
(reprocessed with reuse_message, etc.). There is an assertion to that effect.
If need be, we can loosen it to requiring that the preceeding optional message
also pass SSL_GET_MESSAGE_DONT_HASH_MESSAGE and then maintain some state to
perform the more accurate assertion, but this is sufficient for now.
Change-Id: If8c87342b291ac041a35885b9b5ee961aee86eab
Reviewed-on: https://boringssl-review.googlesource.com/1630
Reviewed-by: Adam Langley <agl@google.com>
I see no internal users and the existence of a THIRD version encoding
complicates all version-checking logic. Also convert another version check to
SSL_IS_DTLS that was missed earlier.
Change-Id: I60d215f57d44880f6e6877889307dc39dbf838f7
Reviewed-on: https://boringssl-review.googlesource.com/1550
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's d345a24569edf0a966b3d6eaae525f0ca4c5e570)
Change-Id: I038f9f01a1d9379f1ee058b231d80e8b9ce6c2d7
Reviewed-on: https://boringssl-review.googlesource.com/1438
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's 3d5dceac430d7b9b273331931d4d2303f5a2256f)
Change-Id: Ibe30716266e2ee1489c98b922cf53edda096c23c
Reviewed-on: https://boringssl-review.googlesource.com/1437
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's aad61c0a57a3b6371496034db61675abcdb81811.)
Change-Id: I2fb0ea93b6e812e19723ada3351f842cc7b2fa91
Reviewed-on: https://boringssl-review.googlesource.com/1436
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's 8ca4c4b25e050b881f3aad7017052842b888722d.)
Change-Id: I387e3f6467a0041f6367965ed3c1ad4377b9ac08
Reviewed-on: https://boringssl-review.googlesource.com/1435
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's 0598468fc04fb0cf2438c4ee635b587aac1bcce6)
Change-Id: I4849498eabb45ec973fcb988d639b23145891e25
Reviewed-on: https://boringssl-review.googlesource.com/1434
Reviewed-by: Adam Langley <agl@google.com>
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>
(Imported from upstream's 49850075555893c9c60d5b981deb697f3b9515ea)
Change-Id: Ie40007184f6194ba032b4213c18d36254e80aaa6
Reviewed-on: https://boringssl-review.googlesource.com/1432
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
It's current a void* and gets explicitly cast everywhere. Make it a uint8_t and
only add the casts when converting it come init_buf, which internally stores a
char*.
Change-Id: I28bed129e46ed37ee1ce378d5c3bd0738fc1177f
Reviewed-on: https://boringssl-review.googlesource.com/1163
Reviewed-by: Adam Langley <agl@google.com>
A buffer overrun attack can be triggered by sending invalid DTLS fragments
to an OpenSSL DTLS client or server. This is potentially exploitable to
run arbitrary code on a vulnerable client or server.
Fixed by adding consistency check for DTLS fragments.
Thanks to Jüri Aedla for reporting this issue.
(Imported from upstream's eb6508d50c9a314b88ac155bd378cbd79a117c92)
Unnecessary recursion when receiving a DTLS hello request can be used to
crash a DTLS client. Fixed by handling DTLS hello request without
recursion.
Thanks to Imre Rad (Search-Lab Ltd.) for discovering this issue.
(Imported from upstream's 8942b92c7cb5fa144bd79b7607b459d0b777164c)
A missing bounds check in the handling of the TLS heartbeat extension
can be used to reveal up to 64k of memory to a connected client or
server.
Thanks for Neel Mehta of Google Security for discovering this bug and to
Adam Langley <agl@chromium.org> and Bodo Moeller <bmoeller@acm.org> for
preparing the fix (CVE-2014-0160)
(Imported from upstream's 7e840163c06c7692b796a93e3fa85a93136adbb2)
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
