Without SSL_MODE_AUTO_RETRY, even blocking mode will return
SSL_ERROR_WANT_{READ|WRITE} in the event of a renegotiation.
The comments in the code speak only of "nasty problems" unless this is
done. The original commit that added SSL_MODE_AUTO_RETRY
(54f10e6adce56eb2e59936e32216162aadc5d050) gives a little more detail:
The [...] behaviour is needed by applications such as s_client and
s_server that use select() to determine when to use SSL_read.
Without the -nbio flag, s_client will use select() to find when the
socket is readable and then call SSL_read with a blocking socket.
However, this will still block in the event of an incomplete record, so
the delay is already unbounded. This it's very unclear what the point of
this behaviour ever was.
Perhaps if the read and write paths were different sockets where the
read socket was non-blocking but the write socket was blocking. But that
seems like an implausible situation to worry too much about.
Change-Id: I9d9f2526afc2e0fd0e5440e9a047f419a2d61afa
Reviewed-on: https://boringssl-review.googlesource.com/2140
Reviewed-by: Adam Langley <agl@google.com>
This resolves a pile of MSVC warnings in Chromium.
Change-Id: Ib9a29cb88d8ed8ec4118d153260f775be059a803
Reviewed-on: https://boringssl-review.googlesource.com/1865
Reviewed-by: Adam Langley <agl@google.com>
Update SSL_OP_ALL to account for SSL_OP_CRYPTOPRO_TLSEXT_BUG being gone,
and update ssl3_setup_write_buffer to account for SSL_MODE_CBC_RECORD_SPLITTING
rather than the now defunct SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS.
Also remove SSL_OP_TLS_BLOCK_PADDING_BUG. This is to allow for a buggy peer
which pads CBC with N bytes of value N rather than N+1 bytes of value N. This
quirk has been broken since CBC padding checks became constant-time, as
demonstrated by this attempt at a test. (Instead of just decrementing
padding_length, it needs to also keep track of a separate padding_value and not
decrement that one.)
https://boringssl-review.googlesource.com/#/c/1690/
(The quirk would also fall over anyway if the buggy client ever did a session
resumption; then the server speaks first rather than the client, and the quirk
triggered on reading the first encrypted record from the peer.)
Change-Id: I19942dc629a47832aead77a46bb50e0b0a9780b3
Reviewed-on: https://boringssl-review.googlesource.com/1694
Reviewed-by: Adam Langley <agl@google.com>
Those codepaths are never hit.
Change-Id: Ib6908ebe90ab667774785298fdc3f96acc4b50df
Reviewed-on: https://boringssl-review.googlesource.com/1693
Reviewed-by: Adam Langley <agl@google.com>
Upstream originally sampled the Finished message's hash at ChangeCipherSpec,
but our patches to add messages between the two complicated this. Move DTLS to
this path, but use the new SSL_GET_MESSAGE_DONT_HASH_MESSAGE flag to avoid
special-casing message types in ssl3_get_message.
Change-Id: I9c8ddd9cc500c94dff2ec2f696f89d50ab01b3ad
Reviewed-on: https://boringssl-review.googlesource.com/1632
Reviewed-by: Adam Langley <agl@google.com>
They weren't updated to account for DTLS 1.2.
Change-Id: I81b3bfcb84a46d7b233bb567976a7de37bc46b92
Reviewed-on: https://boringssl-review.googlesource.com/1503
Reviewed-by: Adam Langley <agl@google.com>
When the write size was exactly SSL3_RT_MAX_PLAIN_LENGTH+1 and record
splitting is needed, an extra byte would be added to the max size of the
message to be written. This would cause the requested size to not exceed
the max. If the SSL_WANT_WRITE error were returned, the next packet
would not get the extra byte added to the max packet size since
record_split_done is set. Since a different set of arguments
(SSL3_RT_MAX_PLAIN_LENGTH+1 vs SSL3_RT_MAX_PLAIN_LENGTH) would be passed
to do_ssl3_write, it would return an "SSL3_WRITE_PENDING:bad write
retry" error.
To avoid a failure in the opposite direction, the max variable increment
is removed as well. This can happen when SSL_MODE_ENABLE_PARTIAL_WRITE
is not enabled and the call to ssl3_write_bytes contains, e.g., a buffer
of 2*SSL3_RT_MAX_PLAIN_LENGTH, where the first call into do_ssl3_write
succeeds writing the first SSL3_RT_MAX_PLAIN_LENGTH bytes, but writing
the second SSL3_RT_MAX_PLAIN_LENGTH bytes fails. This means the first
time the the second section of SSL3_RT_MAX_PLAIN_LENGTH bytes has called
do_ssl3_write with "max" bytes, but next call to ssl3_write_bytes in
turn calls into do_ssl3_write with "max+1" bytes.
Change-Id: Icf8453195c1145a54d31b8e8146801118207df03
Reviewed-on: https://boringssl-review.googlesource.com/1420
Reviewed-by: Kenny Root <kroot@google.com>
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
A modern TLS library without full support for TLS does not make sense.
Change-Id: I032537d1412f6e4effc9a2dd47123baf0084b4c6
Reviewed-on: https://boringssl-review.googlesource.com/1382
Reviewed-by: Adam Langley <agl@google.com>
Now that the flag is set accurately, use it to enforce that the handshake and
CCS synchronization. If EXPECT_CCS is set, enforce that:
(a) No handshake records may be received before ChangeCipherSpec.
(b) There is no pending handshake data at the point EXPECT_CCS is set.
Change-Id: I04b228fe6a7a771cf6600b7d38aa762b2d553f08
Reviewed-on: https://boringssl-review.googlesource.com/1299
Reviewed-by: Adam Langley <agl@google.com>
Only accept change cipher spec when it is expected instead of at any
time. This prevents premature setting of session keys before the master
secret is determined which an attacker could use as a MITM attack.
Thanks to KIKUCHI Masashi (Lepidum Co. Ltd.) for reporting this issue
and providing the initial fix this patch is based on.
(Imported from upstream's 77719aefb8f549ccc7f04222174889615d62057b)
This patch removes support for empty records (which is almost
universally disabled via SSL_OP_ALL) and adds optional support for 1/n-1
record splitting.
The latter is not enabled by default, since it's not typically used on
servers, but it should be enabled in web browsers since there are known
attacks in that case (see BEAST).
Limit the number of empty records that will be processed consecutively
in order to prevent ssl3_get_record from never returning.
Reported by "oftc_must_be_destroyed" and George Kadianakis.
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
