Commit Graph

17 Commits

Author SHA1 Message Date
David Benjamin
b8d28cf532 Factor out the buffering and low-level record code.
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>
2015-08-28 22:01:02 +00:00
Adam Langley
cc1e3df75c Make CBS_get_any_asn1_element accept only DER.
This change makes |CBS_get_any_asn1_element| only handle DER elements.
Another function, |CBS_get_any_ber_asn1_element| is exposed internally
for the cases where we need to process BER data.

Change-Id: I544141a1a3d7913986352a8fd9a6d00b9f282652
Reviewed-on: https://boringssl-review.googlesource.com/4994
Reviewed-by: Adam Langley <agl@google.com>
2015-06-03 22:08:16 +00:00
Adam Langley
0976096224 bytestring: Test out_header_len != NULL before writing.
The documentation for |CBS_get_any_asn1_element| says that
|out_header_len| may be NULL, but in the case of an indefinite-length
element it would be written unconditionally.

Thanks to Doug Hogan for noticing this.

Change-Id: I17609b3465df73d42dd9efd75e783159aa99a59b
Reviewed-on: https://boringssl-review.googlesource.com/4993
Reviewed-by: Adam Langley <agl@google.com>
2015-06-03 22:07:40 +00:00
David Benjamin
22ccc2d8f1 Remove unnecessary NULL checks, part 1.
First batch of the alphabet.

Change-Id: If4e60f4fbb69e04eb4b70aa1b2240e329251bfa5
Reviewed-on: https://boringssl-review.googlesource.com/4514
Reviewed-by: Adam Langley <agl@google.com>
2015-05-04 23:05:17 +00:00
David Benjamin
5933723b7b Check for leading zeros in CBS_get_asn1_uint64.
The encoding of an INTEGER should not have leading zeros, except to pad for the
sign bit.

Change-Id: I80d22818cf1d2ca9d27e215620392e1725372aa5
Reviewed-on: https://boringssl-review.googlesource.com/4218
Reviewed-by: Adam Langley <agl@google.com>
2015-04-06 20:54:53 +00:00
David Benjamin
c9a202fee3 Add in missing curly braces part 1.
Everything before crypto/ec.

Change-Id: Icbfab8e4ffe5cc56bf465eb57d3fdad3959a085c
Reviewed-on: https://boringssl-review.googlesource.com/3401
Reviewed-by: Adam Langley <agl@google.com>
2015-02-11 19:31:01 +00:00
Adam Langley
7571292eac Extended master secret support.
This change implements support for the extended master secret. See
https://tools.ietf.org/html/draft-ietf-tls-session-hash-01
https://secure-resumption.com/

Change-Id: Ifc7327763149ab0894b4f1d48cdc35e0f1093b93
Reviewed-on: https://boringssl-review.googlesource.com/1930
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2014-10-24 21:19:44 +00:00
David Benjamin
83fd6b686f Reimplement d2i_SSL_SESSION with CBS.
Do away with all those unreadable macros. Also fix many many memory leaks in
the SSL_SESSION reuse case. Add a number of helper functions in CBS to help
with parsing optional fields.

Change-Id: I2ce8fd0d5b060a1b56e7f99f7780997fabc5ce41
Reviewed-on: https://boringssl-review.googlesource.com/1998
Reviewed-by: Adam Langley <agl@google.com>
2014-10-24 18:26:41 +00:00
David Benjamin
fbe6f498cd The empty contents are not a valid ASN.1 INTEGER.
Zero is encoded as a single zero octet. Per X.690, 8.3.1:

  The encoding of an integer value shall be primitive. The contents octets
  shall consist of one or more octets.

Change-Id: If4304a2be5117b71446a3a62a2b8a6124f85a202
Reviewed-on: https://boringssl-review.googlesource.com/2010
Reviewed-by: Adam Langley <agl@google.com>
2014-10-24 18:26:11 +00:00
David Benjamin
b698617007 Add CBS_peek_asn1_tag.
Intended to make parsing ASN.1 structures with OPTIONAL elements easier. (Just
attempting to parse the next tag doesn't distinguish between a malformed CBS
which has now been partially advanced and an optional tag mismatch.)

Change-Id: Idceb3dfd6ec028e87e1bc5aaddcec177b0c32150
Reviewed-on: https://boringssl-review.googlesource.com/1995
Reviewed-by: Adam Langley <agl@google.com>
2014-10-20 19:20:26 +00:00
David Benjamin
9b04d657be Export CBS_get_any_asn1_element.
Useful for parsing things when you don't know what tag to expect (e.g. a
CHOICE). Also allow its operands to be NULL, so that it can be used to skip
arbitrary elements.

Delete CBS_ASN1_ANY which wasn't doing anything.

Change-Id: I56413e68b4f2e13860ea3e55373d5830713d7e5c
Reviewed-on: https://boringssl-review.googlesource.com/1661
Reviewed-by: Adam Langley <agl@google.com>
2014-08-28 00:45:30 +00:00
Adam Langley
9c01e00c2e Rework support for ASN.1 BER.
Previously, the ASN.1 functions in bytestring were capable of processing
indefinite length elements when the _ber functions were used. That works
well enough for PKCS#3, but NSS goes a bit crazy with BER encoding and
PKCS#12. Rather than complicate the core bytestring functions further,
the BER support is removed from them and moved to a separate function
that converts from BER to DER (if needed).

Change-Id: I2212b28e99bab9fab8c61f80d2012d3e5a3cc2f0
Reviewed-on: https://boringssl-review.googlesource.com/1591
Reviewed-by: Adam Langley <agl@google.com>
2014-08-25 21:38:08 +00:00
David Benjamin
c10dde465e Only allow indefinite lengths for constructed types.
Equivalent of e532f823d6 for CBS.

Change-Id: I5c31f589db119115c78da3f0d592d71254836f89
Reviewed-on: https://boringssl-review.googlesource.com/1508
Reviewed-by: Adam Langley <agl@google.com>
2014-08-14 16:54:56 +00:00
David Benjamin
22f9bccde5 Port ssl3_get_client_hello to CBS.
Also fix some DTLS cookie bugs. rcvd_cookie is never referenced after being
saved (and the length isn't saved, so it couldn't be used anyway), and the
cookie verification failed to check the length.

For convenience, add a CBS_mem_equal helper function. Saves a bit of
repetition.

Change-Id: I187137733b069f0ac8d8b1bf151eeb80d388b971
Reviewed-on: https://boringssl-review.googlesource.com/1174
Reviewed-by: Adam Langley <agl@google.com>
2014-07-15 18:30:09 +00:00
David Benjamin
ed43958853 Port ssl3_get_key_exchange to CBS.
Also tidy up some variable names and update RSA_verify call for it no longer
returning -1. Add CBS helper functions for dealing with C strings.

Change-Id: Ibc398d27714744f5d99d4f94ae38210cbc89471a
Reviewed-on: https://boringssl-review.googlesource.com/1164
Reviewed-by: Adam Langley <agl@google.com>
2014-07-14 23:37:29 +00:00
David Benjamin
03973096f4 Port ServerHello extension parsing to CBS.
This gives us systematic bounds-checking on all the parses. Also adds a
convenience function, CBS_memdup, for saving the current contents of a CBS.

Change-Id: I17dad74575f03121aee3f771037b8806ff99d0c3
Reviewed-on: https://boringssl-review.googlesource.com/1031
Reviewed-by: Adam Langley <agl@google.com>
2014-06-26 20:42:27 +00:00
Adam Langley
95c29f3cd1 Inital import.
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).

(This change contains substantial changes from the original and
effectively starts a new history.)
2014-06-20 13:17:32 -07:00