The existing logic gets confused in a number of cases around close_notify vs.
fatal alert. SSL_shutdown, while still pushing to the error queue, will fail to
notice alerts. We also get confused if we try to send a fatal alert when we've
already sent something else.
Change-Id: I9b1d217fbf1ee8a9c59efbebba60165b7de9689e
Reviewed-on: https://boringssl-review.googlesource.com/7952
Reviewed-by: David Benjamin <davidben@google.com>
SSL_RECEIVED_SHUTDOWN checks in the record layer happen in two different
places. Some operations (but not all) check it, and so does read_bytes. Move it
to get_record.
This check should be at a low-level since it is otherwise duplicated in every
operation. It is also a signal which originates from around the peer's record
layer, so it makes sense to check it near the same code. (This one's in
get_record which is technically lower-level than read_bytes, but we're trying
to get rid of read_bytes. They're very coupled functions.)
Also, if we've seen a fatal alert, replay an error, not an EOF.
Change-Id: Idec35c5068ddabe5b1a9145016d8f945da2421cf
Reviewed-on: https://boringssl-review.googlesource.com/7436
Reviewed-by: David Benjamin <davidben@google.com>
We reset it to SSL_NOTHING at the start of ever SSL_get_error-using operation.
Then we only set it to a non-NOTHING value in the rest of the stack on error
paths.
Currently, ssl->rwstate is set all over the place. Sometimes the pattern is:
ssl->rwstate = SSL_WRITING;
if (BIO_write(...) <= 0) {
goto err;
}
ssl->rwstate = SSL_NOTHING;
Sometimes we only set it to the non-NOTHING value on error.
if (BIO_write(...) <= 0) {
ssl->rwstate = SSL_WRITING;
}
ssl->rwstate = SSL_NOTHING;
Sometimes we just set it to SSL_NOTHING far from any callback in random places.
The third case is arbitrary and clearly should be removed.
But, in the second case, we sometimes forget to undo it afterwards. This is
largely harmless since an error in the error queue overrides rwstate, but we
don't always put something in the error queue (falling back to
SSL_ERROR_SYSCALL for "I'm not sure why it failed. Perhaps it was one of your
callbacks? Check your errno equivalent."), but in that case a stray rwstate
value will cause it to be wrong.
We could fix the cases where we fail to set SSL_NOTHING on success cases, but
this doesn't account for there being multiple SSL_get_error operations. The
consumer may have an SSL_read and an SSL_write running concurrently. Instead,
it seems the best option is to lift the SSL_NOTHING reset to the operations and
set SSL_WRITING and friends as in the second case.
(Someday hopefully we can fix this to just be an enum that is internally
returned. It can convert to something stateful at the API layer.)
Change-Id: I54665ec066a64eb0e48a06e2fcd0d2681a42df7f
Reviewed-on: https://boringssl-review.googlesource.com/7453
Reviewed-by: David Benjamin <davidben@google.com>
This is just kind of a silly thing to do. NSS doesn't allow them either. Fatal
alerts would kill the connection regardless and warning alerts are useless. We
previously stopped accepting fragmented alerts but still allowed them doubled
up.
This is in preparation for pulling the shared alert processing code between TLS
and DTLS out of read_bytes into some common place.
Change-Id: Idbef04e39ad135f9601f5686d41f54531981e0cf
Reviewed-on: https://boringssl-review.googlesource.com/7451
Reviewed-by: Emily Stark (Dunn) <estark@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
This removes the final use of in_handshake. Note that there is still a
rentrant call of read_bytes -> handshake_func when we see a
HelloRequest. That will need to be signaled up to ssl_read_impl
separately out of read_app_data.
Change-Id: I823de243f75e6b73eb40c6cf44157b4fc21eb8fb
Reviewed-on: https://boringssl-review.googlesource.com/7439
Reviewed-by: David Benjamin <davidben@google.com>
This removes one use of in_handshake and consolidates some DTLS and TLS
code.
Change-Id: Ibbdd38360a983dabfb7b18c7bd59cb5e316b2adb
Reviewed-on: https://boringssl-review.googlesource.com/7435
Reviewed-by: David Benjamin <davidben@google.com>
fatal_alert isn't read at all right now, and warn_alert is only checked
for close_notify. We only need three states:
- Not shutdown.
- Got a fatal alert (don't care which).
- Got a warning close_notify.
Leave ssl->shutdown alone for now as it's tied up with SSL_set_shutdown
and friends. To distinguish the remaining two, we only need a boolean.
Change-Id: I5877723af82b76965c75cefd67ec1f981242281b
Reviewed-on: https://boringssl-review.googlesource.com/7434
Reviewed-by: David Benjamin <davidben@google.com>
Change-Id: I6267c9bfb66940d0b6fe5368514210a058ebd3cc
Reviewed-on: https://boringssl-review.googlesource.com/7494
Reviewed-by: Emily Stark (Dunn) <estark@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Change-Id: I5b38e2938811520f52ece6055245248c80308b4d
Reviewed-on: https://boringssl-review.googlesource.com/7416
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Both are connection state rather than configuration state. Notably this
cuts down more of SSL_clear that can't just use ssl_free + ssl_new.
Change-Id: I3c05b3ae86d4db8bd75f1cd21656f57fc5b55ca9
Reviewed-on: https://boringssl-review.googlesource.com/6835
Reviewed-by: Adam Langley <alangley@gmail.com>
That we're half and half is really confusing.
Change-Id: I1c2632682e8a3e63d01dada8e0eb3b735ff709ce
Reviewed-on: https://boringssl-review.googlesource.com/6785
Reviewed-by: Adam Langley <agl@google.com>
There's no need to track consumed bytes, so rr->data and rr->off may be
merged together.
Change-Id: I8842d005665ea8b4d4a0cced941f3373872cdac4
Reviewed-on: https://boringssl-review.googlesource.com/6644
Reviewed-by: Adam Langley <agl@google.com>
This uses ssl3_read_bytes for now. We still need to dismantle that
function and then invert the handshake state machine, but this gets
things closer to the right shape as an intermediate step and is a large
chunk in itself. It simplifies a lot of the CCS/handshake
synchronization as a lot of the invariants much more clearly follow from
the handshake itself.
Tests need to be adjusted since this changes some error codes. Now all
the CCS/Handshake checks fall through to the usual
SSL_R_UNEXPECTED_RECORD codepath. Most of what used to be a special-case
falls out naturally. (If half of Finished was in the same record as the
pre-CCS message, that part of the handshake record would have been left
unconsumed, so read_change_cipher_spec would have noticed, just like
read_app_data would have noticed.)
Change-Id: I15c7501afe523d5062f0e24a3b65f053008d87be
Reviewed-on: https://boringssl-review.googlesource.com/6642
Reviewed-by: Adam Langley <agl@google.com>
TLS resets it in t1_enc.c while DTLS has it sprinkled everywhere.
Change-Id: I78f0f0e646b4dc82a1058199c4b00f2e917aa5bc
Reviewed-on: https://boringssl-review.googlesource.com/6511
Reviewed-by: Adam Langley <agl@google.com>
That function doesn't do anything useful for DTLS. It's meant for tracking the
rest of the record we've already committed to by writing half of one. But one
cannot write half a datagram, so DTLS never tracks this. Just call
ssl_write_buffer_flush straight and don't touch wpend_*.
Change-Id: Ibe191907d64c955c7cfeefba26f5c11ad5e4b939
Reviewed-on: https://boringssl-review.googlesource.com/6418
Reviewed-by: Adam Langley <agl@google.com>
This callback is some combination of arguably useful stuff (bracket
handshakes, alerts) and completely insane things (find out when the
state machine advances). Deprecate the latter.
Change-Id: Ibea5b32cb360b767b0f45b302fd5f1fe17850593
Reviewed-on: https://boringssl-review.googlesource.com/6305
Reviewed-by: Adam Langley <alangley@gmail.com>
ssl.h should be first. Also two lines after includes and the rest of the
file.
Change-Id: Icb7586e00a3e64170082c96cf3f8bfbb2b7e1611
Reviewed-on: https://boringssl-review.googlesource.com/5892
Reviewed-by: Adam Langley <agl@google.com>
Bidirectional shutdown doesn't make sense over DTLS; you can't reuse the
underlying channel after receiving close_notify because the channel is
unordered. This removes one caller of dtls1_read_bytes.
Really close_notify makes no sense in DTLS. It can't even protect
against some kind of truncation because it's all unordered. But continue
to send it in case anything is (unreliably since the channel is lossy)
relying on close_notify to signal some kind of session end. This only
makes SSL_shutdown stop trying to wait for one once we've already
decided to shut down the connection.
BUG=526437
Change-Id: I6afad7cb7209c4aba0b96f9246b04c81d90987a9
Reviewed-on: https://boringssl-review.googlesource.com/5770
Reviewed-by: Adam Langley <agl@google.com>
The old empty record logic discarded the records at a very low-level.
Let the error bubble up to ssl3_read_bytes so the type mismatch logic
may kick in before the empty record is skipped.
Add tests for when the record in question is application data, before
before the handshake and post ChangeCipherSpec.
BUG=521840
Change-Id: I47dff389cda65d6672b9be39d7d89490331063fa
Reviewed-on: https://boringssl-review.googlesource.com/5754
Reviewed-by: Adam Langley <agl@google.com>
This begins decoupling the transport from the SSL state machine. The buffering
logic is hidden behind an opaque API. Fields like ssl->packet and
ssl->packet_length are gone.
ssl3_get_record and dtls1_get_record now call low-level tls_open_record and
dtls_open_record functions that unpack a single record independent of who owns
the buffer. Both may be called in-place. This removes ssl->rstate which was
redundant with the buffer length.
Future work will push the buffer up the stack until it is above the handshake.
Then we can expose SSL_open and SSL_seal APIs which act like *_open_record but
return a slightly larger enum due to other events being possible. Likewise the
handshake state machine will be detached from its buffer. The existing
SSL_read, SSL_write, etc., APIs will be implemented on top of SSL_open, etc.,
combined with ssl_read_buffer_* and ssl_write_buffer_*. (Which is why
ssl_read_buffer_extend still tries to abstract between TLS's and DTLS's fairly
different needs.)
The new buffering logic does not support read-ahead (removed previously) since
it lacks a memmove on ssl_read_buffer_discard for TLS, but this could be added
if desired. The old buffering logic wasn't quite right anyway; it tried to
avoid the memmove in some cases and could get stuck too far into the buffer and
not accept records. (The only time the memmove is optional is in DTLS or if
enough of the record header is available to know that the entire next record
would fit in the buffer.)
The new logic also now actually decrypts the ciphertext in-place again, rather
than almost in-place when there's an explicit nonce/IV. (That accidentally
switched in https://boringssl-review.googlesource.com/#/c/4792/; see
3d59e04bce96474099ba76786a2337e99ae14505.)
BUG=468889
Change-Id: I403c1626253c46897f47c7ae93aeab1064b767b2
Reviewed-on: https://boringssl-review.googlesource.com/5715
Reviewed-by: Adam Langley <agl@google.com>
Take the sequence number as a parameter. Also replace satsub64be with
the boring thing: convert to uint64_t and subtract normally.
BUG=468889
Change-Id: Icab75f872b5e55cf4e9d68b66934ec91afeb198b
Reviewed-on: https://boringssl-review.googlesource.com/5558
Reviewed-by: Adam Langley <agl@google.com>
The split was only needed for buffering records. Likewise, the extra
seq_num field is now unnecessary.
This also fixes a bug where dtls1_process_record will push an error on
the queue if the decrypted record is too large, which dtls1_get_record
will ignore but fail to clear, leaving garbage on the error queue. The
error is now treated as fatal; the reason DTLS silently drops invalid
packets is worrying about ease of DoS, but after SSL_AEAD_CTX_open, the
packet has been authenticated. (Unless it's the null cipher, but that's
during the handshake and the handshake is already DoS-able by breaking
handshake reassembly state.)
The function is still rather a mess. Later changes will clean this up.
BUG=468889
Change-Id: I96a54afe0755d43c34456f76e77fc4ee52ad01e3
Reviewed-on: https://boringssl-review.googlesource.com/5557
Reviewed-by: Adam Langley <agl@google.com>
This still needs significant work, especially the close_notify half, but
clarify the interface and get *_read_bytes out of SSL_PROTOCOL_METHOD.
read_bytes is an implementation detail of those two and get_message
rather than both an implementation detail of get_message for handshake
and a (wholly inappropriate) exposed interface for the other two.
BUG=468889
Change-Id: I7dd23869e0b7c3532ceb2e9dd31ca25ea31128e7
Reviewed-on: https://boringssl-review.googlesource.com/4956
Reviewed-by: Adam Langley <agl@google.com>
The SSL_PROTOCOL_METHOD table needs work, but this makes it clearer
exactly what the shared interface between the upper later and TLS/DTLS
is.
BUG=468889
Change-Id: I38931c484aa4ab3f77964d708d38bfd349fac293
Reviewed-on: https://boringssl-review.googlesource.com/4955
Reviewed-by: Adam Langley <agl@google.com>
Now that WebRTC honors packet boundaries (https://crbug.com/447431), we
can start enforcing them correctly. Configuring read-ahead now does
nothing. Instead DTLS will always set "read-ahead" and also correctly
enforce packet boundaries when reading records. Add tests to ensure that
badly fragmented packets are ignored. Because such packets don't fail
the handshake, the tests work by injecting an alert in the front of the
handshake stream and ensuring the DTLS implementation ignores them.
ssl3_read_n can be be considerably unraveled now, but leave that for
future cleanup. For now, make it correct.
BUG=468889
Change-Id: I800cfabe06615af31c2ccece436ca52aed9fe899
Reviewed-on: https://boringssl-review.googlesource.com/4820
Reviewed-by: Adam Langley <agl@google.com>
This is considerably less scary than swapping out connection state. It also
fixes a minor bug where, if dtls1_do_write had an alert to dispatch and we
happened to retry during a rexmit, it would use the wrong epoch.
BUG=468889
Change-Id: I754b0d46bfd02f797f4c3f7cfde28d3e5f30c52b
Reviewed-on: https://boringssl-review.googlesource.com/4793
Reviewed-by: Adam Langley <agl@google.com>
tls1_enc is now SSL_AEAD_CTX_{open,seal}. This starts tidying up a bit
of the record-layer logic. This removes rr->input, as encrypting and
decrypting records no longer refers to various globals. It also removes
wrec altogether. SSL3_RECORD is now only used to maintain state about
the current incoming record. Outgoing records go straight to the write
buffer.
This also removes the outgoing alignment memcpy and simply calls
SSL_AEAD_CTX_seal with the parameters as appropriate. From bssl speed
tests, this seems to be faster on non-ARM and a bit of a wash on ARM.
Later it may be worth recasting these open/seal functions to write into
a CBB (tweaked so it can be malloc-averse), but for now they take an
out/out_len/max_out trio like their EVP_AEAD counterparts.
BUG=468889
Change-Id: Ie9266a818cc053f695d35ef611fd74c5d4def6c3
Reviewed-on: https://boringssl-review.googlesource.com/4792
Reviewed-by: Adam Langley <agl@google.com>
Nothing should call ssl3_setup_read_buffer or ssl3_setup_write_buffer unless it
intends to write into the buffer. This way buffer management can later be an
implementation detail of the record layer.
Change-Id: Idb0effba00e77c6169764843793f40ec37868b61
Reviewed-on: https://boringssl-review.googlesource.com/4687
Reviewed-by: Adam Langley <agl@google.com>
It's completely redundant with the extend bit. If extend is 0, we're reading a
new record, and rbuf.len is passed. Then it needs to get clamped by ssl3_read_n
post alignment anyway. If extend is 1, we're reading the rest of the current
record and max is always n. (For TLS, we actually could just read more, but not
for DTLS. Basically no one sets it on the TLS side of things, so instead, after
WebRTC's broken DTLS handling is fixed, read_ahead can go away altogether and
DTLS/TLS record layers can be separated.)
This removes ssl3_read_n's callers' dependency on ssl3_setup_read_buffer
setting up rbuf.len.
Change-Id: Iaf11535d01017507a52a33b19240f42984d6cf52
Reviewed-on: https://boringssl-review.googlesource.com/4686
Reviewed-by: Adam Langley <agl@google.com>
They date to https://rt.openssl.org/Ticket/Display.html?id=2533, but no
particularly good justification was given for them. It seems it was just a
bandaid because d1_pkt.c forgot to initialize the buffer. I went through
codesearch for all accesses to SSL3_BUFFER::buf and SSL::packet. They seem
appropriately guarded but for this one.
Change-Id: Ife4e7afdb7a7c137d6be4791542eb5de6dd5b1b6
Reviewed-on: https://boringssl-review.googlesource.com/4685
Reviewed-by: Adam Langley <agl@google.com>
The rest of ssl/ still includes things everywhere, but this at least fixes the
includes that were implicit from ssl/internal.h.
Change-Id: I7ed22590aca0fe78af84fd99a3e557f4b05f6782
Reviewed-on: https://boringssl-review.googlesource.com/4281
Reviewed-by: Adam Langley <agl@google.com>
Match the other internal headers.
Change-Id: Iff7e2dd06a1a7bf993053d0464cc15638ace3aaa
Reviewed-on: https://boringssl-review.googlesource.com/4280
Reviewed-by: Adam Langley <agl@google.com>
This conceivably has a use, but NSS doesn't do this buffer either and it still
suffers from the same problems as the other uses of record_pqueue. This removes
the last use of record_pqueue. It also opens the door to removing pqueue
altogether as it isn't the right data structure for either of the remaining
uses either. (It's not clear it was right for record_pqueue either, but I don't
feel like digging into this code.)
Change-Id: If8a43e7332b3cd11a78a516f3e8ebf828052316f
Reviewed-on: https://boringssl-review.googlesource.com/4239
Reviewed-by: Adam Langley <agl@google.com>
It was only ever enabled for handshake and alert messages. The comments cite
renego as a use case though even then I'm not clear on why. The only use I see
is if, say, the Finished message and ClientKeyExchange came in out-of-order.
DTLS is unreliable so leaning on retransmit seems fine, and usually flights
will be packed into one packet where possible. NSS doesn't have any such
buffer and doesn't seem to have problems.
The buffering mechanism is also rather dubious. It stows away the entire packet
and read buffer---all 16K of it---and there may have been other records in that
packet.
Change-Id: Ic3b7bf817be380dc73102eec62c690ed093e6667
Reviewed-on: https://boringssl-review.googlesource.com/4238
Reviewed-by: Adam Langley <agl@google.com>
Also check for overflow, although it really shouldn't happen.
Change-Id: I34dfe8eaf635aeaa8bef2656fda3cd0bad7e1268
Reviewed-on: https://boringssl-review.googlesource.com/4235
Reviewed-by: Adam Langley <agl@google.com>
It's still rather a mess, but this is at least somewhat clearer. The old one
had a lot of remnants of compression, etc.
Change-Id: Iffcb4dd4e8c4ab14f60abf917d22b7af960c93ba
Reviewed-on: https://boringssl-review.googlesource.com/4233
Reviewed-by: Adam Langley <agl@google.com>
This mostly[*] doesn't matter for TLS since the message would have been
rejected anyway, but, in DTLS, if the peer rejects our Finished, it will send
an encrypted alert. This will then cause it to hang, which isn't very helpful.
I've made the change on both TLS and DTLS so the two protocols don't diverge on
this point. It is true that we're accepting nominally encrypted and
authenticated alerts before Finished, but, prior to ChangeCipherSpec, the
alerts are sent in the clear anyway so an attacker could already inject alerts.
A consumer could only be sensitive to it being post-CCS if it was watching
msg_callback. The only non-debug consumer of msg_callback I've found anywhere
is some hostapd code to detect Heartbeat.
See https://code.google.com/p/webrtc/issues/detail?id=4403 for an instance
where the equivalent behavior in OpenSSL masks an alert.
[*] This does change behavior slightly if the peer sends a warning alert
between CCS and Finished. I believe this is benign as warning alerts are
usually ignored apart from info_callback and msg_callback. The one exception is
a close_notify which is a slightly new state (accepting close_notify during a
handshake seems questionable...), but they're processed pre-CCS too.
Change-Id: Idd0d49b9f9aa9d35374a9f5e2f815cdb931f5254
Reviewed-on: https://boringssl-review.googlesource.com/3883
Reviewed-by: Adam Langley <agl@google.com>
If the peer fragments Finished into multiple pieces, there is no need to
retransmit multiple times.
Change-Id: Ibf708ad079e1633afd420ff1c9be88a80020cba9
Reviewed-on: https://boringssl-review.googlesource.com/3762
Reviewed-by: Adam Langley <agl@google.com>
Align the DTLS and TLS implementations more. s3_pkt.c's version still has
remnants of fragmentable alerts and only one side marks some variables as
const. Also use warning/fatal constants rather than the numbers with comments.
Change-Id: Ie62d3af1747b6fe4336496c047dfccc9d71fde3f
Reviewed-on: https://boringssl-review.googlesource.com/3562
Reviewed-by: Adam Langley <agl@google.com>
The new V2ClientHello sniff asserts, for safety, that nothing else has
initialized the record layer before it runs. However, OpenSSL allows you to
avoid explicitly calling SSL_connect/SSL_accept and instead let
SSL_read/SSL_write implicitly handshake for you. This check happens at a fairly
low-level in the ssl3_read_bytes function, at which point the record layer has
already been initialized.
Add some tests to ensure this mode works.
(Later we'll lift the handshake check to a higher-level which is probably
simpler.)
Change-Id: Ibeb7fb78e5eb75af5411ba15799248d94f12820b
Reviewed-on: https://boringssl-review.googlesource.com/3334
Reviewed-by: Adam Langley <agl@google.com>
The check on the DTLS side was broken anyway. On the TLS side, the spec does
say to ignore them, but there should be no need for this in future-proofing and
NSS doesn't appear to be lenient here. See also
https://boringssl-review.googlesource.com/#/c/3233/
Change-Id: I0846222936c5e08acdcfd9d6f854a99df767e468
Reviewed-on: https://boringssl-review.googlesource.com/3290
Reviewed-by: Adam Langley <agl@google.com>
Nothing recognized through those codepaths is fragmentable in DTLS. Also remove
an unnecessary epoch check. It's not possible to process a record from the
wrong epoch.
Change-Id: I9d0f592860bb096563e2bdcd2c8e50a0d2b65f59
Reviewed-on: https://boringssl-review.googlesource.com/3232
Reviewed-by: Adam Langley <agl@google.com>
We have no use for DTLS renego and it's even more complex than TLS renego.
Change-Id: I8680ab361cc8761dd7fc8dfb1bfe1ff4abc6612f
Reviewed-on: https://boringssl-review.googlesource.com/3218
Reviewed-by: Adam Langley <agl@google.com>
This regressed in e95d20dcb8. EVP_AEAD will push
errors on the error queue (unlike the EVP_CIPHER codepath which checked
everything internally to ssl/ and didn't bother pushing anything). This meant
that a dropped packet would leave junk in the error queue.
Later, when SSL_read returns <= 0 (EOF or EWOULDBLOCK), the non-empty error
queue check in SSL_get_error kicks in and SSL_read looks to have failed.
BUG=https://code.google.com/p/webrtc/issues/detail?id=4214
Change-Id: I1e5e41c77a3e5b71e9eb0c72294abf0da677f840
Reviewed-on: https://boringssl-review.googlesource.com/2982
Reviewed-by: Adam Langley <agl@google.com>
