Commit Graph

705 Commits

Author SHA1 Message Date
David Benjamin
a31c5bf2cc Make pem_str const-correct.
They're always constant literals.

Change-Id: I8acaaf2a8c95b02bc8b9b13740ce40044a483394
Reviewed-on: https://boringssl-review.googlesource.com/5346
Reviewed-by: Adam Langley <agl@google.com>
2015-07-07 01:11:58 +00:00
David Benjamin
42ae3adcf6 Remove info field on EVP_PKEY_ASN1_METHOD.
Nothing ever reads it.

Change-Id: Id375c461aa2feb6877a14e19eb2daefec7a03f89
Reviewed-on: https://boringssl-review.googlesource.com/5345
Reviewed-by: Adam Langley <agl@google.com>
2015-07-07 01:11:46 +00:00
David Benjamin
b9c579db6d Add crypto/bytestring-based BIGNUM DER functions.
RSA and ECDSA will both require being able to convert ASN.1 INTEGERs to
and from DER. Don't bother handling negative BIGNUMs for now. It doesn't
seem necessary and saves bothering with two's-complement vs
sign-and-magnitude.

BUG=499653

Change-Id: I1e80052067ed528809493af73b04f82539d564ff
Reviewed-on: https://boringssl-review.googlesource.com/5268
Reviewed-by: Adam Langley <agl@google.com>
2015-07-07 00:47:39 +00:00
Khem Raj
241364c6f4 Demand for newer POSIX macro
Reason for change: Define _POSIX_C_SOURCE such that it demands correct
posix interfaces, netdb.h declares interfaces such as
getaddrinfo if __USE_POSIX, i.e. POSIX.1:1990 or later.
However, these interfaces were new in the 2001 edition of POSIX
therefore ask for Extension from POSIX.1:2001 since we use addrinfo
structure here.

Change-Id: Icb1c92745d1a0ca958108ae80c270c630628729e
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Reviewed-on: https://boringssl-review.googlesource.com/5253
Reviewed-by: Adam Langley <agl@google.com>
2015-07-06 22:41:16 +00:00
David Benjamin
fd5603666c Call ERR_clear_error after functions that are expected to fail.
Otherwise we leave stuff in the error queue for the next test.

Change-Id: I167b7420b9d3fada69d1d35ac8132dd21a04797c
Reviewed-on: https://boringssl-review.googlesource.com/5310
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 21:47:44 +00:00
David Benjamin
cce5a98efb Remove EVP_PKEY_dup.
All callers have been moved to EVP_PKEY_up_ref. (Neither spelling exists
upstream so we only had our own callers to move.)

Change-Id: I267f14054780fe3d6dc1170b7b6ae3811a0d1a9a
Reviewed-on: https://boringssl-review.googlesource.com/5291
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 21:38:39 +00:00
David Benjamin
76e9a2ab97 Add tests for low-level AES functions.
May as well. Depending on the implementation chosen in cipher/e_aes.c,
AES_encrypt may or may not be hit, so test this entry point explicitly.

Change-Id: Icb02bf3f4b6e5ecbb9e5111f44fbb1b267ead6c3
Reviewed-on: https://boringssl-review.googlesource.com/5312
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 21:37:57 +00:00
David Benjamin
f078639d5a Test both streaming and single-shot EVP_CIPHER operations.
Run a variant of every test which feeds the input in one byte at a time.

Change-Id: I2a05372ea0fbb20484493fd14e9f3c23fbb8d875
Reviewed-on: https://boringssl-review.googlesource.com/5301
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 21:36:43 +00:00
David Benjamin
a8653208ec Add CBB_zero to set a CBB to the zero state.
One tedious thing about using CBB is that you can't safely CBB_cleanup
until CBB_init is successful, which breaks the general 'goto err' style
of cleanup. This makes it possible:

  CBB_zero ~ EVP_MD_CTX_init
  CBB_init ~ EVP_DigestInit
  CBB_cleanup ~ EVP_MD_CTX_cleanup

Change-Id: I085ecc4405715368886dc4de02285a47e7fc4c52
Reviewed-on: https://boringssl-review.googlesource.com/5267
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:45:43 +00:00
David Benjamin
d63307199a Re-wrap kOAEPCipherText from rsa_test.
While I'm here, make them consistent with the keys.

Change-Id: Ib2804dd4f18bbb3b3735fb7772fca590e0d6d624
Reviewed-on: https://boringssl-review.googlesource.com/5266
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:40:22 +00:00
David Benjamin
cb41d77029 Fix kTwoPrimeKey and kSixPrimeKey samples in rsa_test.
They weren't valid DER. Some lengths were encoded with one more byte
than necessary.

Change-Id: I94c8c525ade835fdeca115af98ab7e5910d2aeb2
Reviewed-on: https://boringssl-review.googlesource.com/5265
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:40:04 +00:00
David Benjamin
d13a5e15d4 Fix crypto/bytestring test for too long lengths.
kData5 was meant to test lengths that are too long, but the input
gets rejected earlier for not using short-form encoding. Switch it to
testing a badly encoded element of length 128, the shortest element that
uses long-form encoding.

Change-Id: I35f4df89bfa7a681698eda569c525b5871288487
Reviewed-on: https://boringssl-review.googlesource.com/5264
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:39:16 +00:00
David Benjamin
1db476e7a5 Include openssl/chacha.h rather than duplicate the prototype.
Less chance of problems should the prototype ever change. This doesn't
make it any more or less a circular dependency. (It actually isn't;
crypto/chacha doesn't use crypto/rand and CMakeLists.txt actually puts
rand above chacha anyway.)

Change-Id: Ia80289f801f76551737233f158755aac99ddd74a
Reviewed-on: https://boringssl-review.googlesource.com/5262
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:35:56 +00:00
Adam Langley
5021b223d8 Convert the renegotiation extension to the new system.
This change also switches the behaviour of the client. Previously the
client would send the SCSV rather than the extension, but now it'll only
do that for SSLv3 connections.

Change-Id: I67a04b8abbef2234747c0dac450458deb6b0cd0a
Reviewed-on: https://boringssl-review.googlesource.com/5143
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 19:30:53 +00:00
Adam Langley
614c66a2f8 Add infrastructure for better extension handling.
Rather than four massive functions that handle every extension,
organise the code by extension with four smaller functions for each.

Change-Id: I876b31dacb05aca9884ed3ae7c48462e6ffe3b49
Reviewed-on: https://boringssl-review.googlesource.com/5142
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 18:25:28 +00:00
David Benjamin
705076ac91 Handle EINTR in open and dup calls in urandom.c.
Per review comment in
https://boringssl-review.googlesource.com/#/c/5302/7/crypto/rand/urandom.c

Change-Id: I9c279524a452cb97c60354213cbc6e2aeabe0bfa
Reviewed-on: https://boringssl-review.googlesource.com/5311
Reviewed-by: Adam Langley <agl@google.com>
2015-07-01 00:50:05 +00:00
David Benjamin
de24aadc5b Add RAND_set_urandom_fd.
Chromium uses a zygote process and a sandbox on Linux. In order for RAND_bytes
to be functional and guaranteed fork-safe inside the renderers, /dev/urandom
must be prewarmed. Calling RAND_bytes initializes a thread-local ChaCha20 key
when rdrand is available. So that key is fork-safe and to avoid tempting any
dragons by touching pthreads APIs before a non-exec fork, add a
RAND_set_urandom_fd API. It allows the consumer to supply the /dev/urandom fd
and promises to be fork-safe, both in initializing key material and use of
pthreads.

This doesn't affect any current shipping versions of Chrome.

BUG=462040

Change-Id: I1037e21e525918971380e4ea1371703c8237a0b0
Reviewed-on: https://boringssl-review.googlesource.com/5302
Reviewed-by: Adam Langley <agl@google.com>
2015-06-30 21:41:42 +00:00
David Benjamin
6cacac033b Promote SSL_CTX_[gs]et_tlsext_ticket_keys to functions.
BUG=404754

Change-Id: Iae75a7ab24d4aa3b30edf578cbfc1058aeadd863
Reviewed-on: https://boringssl-review.googlesource.com/5233
Reviewed-by: Adam Langley <agl@google.com>
2015-06-25 22:39:36 +00:00
David Benjamin
65ee9b7ce9 Remove EVP_PKEY_HMAC.
This removes EVP_PKEY_HMAC and all the support code around it. EVP_MD requires
a lot of extra glue to support HMAC. This lets us prune it all away.

As a bonus, it removes a (minor) dependency from EVP to the legacy ASN.1 stack.

Change-Id: I5a9e3e39f518429828dbf13d14647fb37d9dc35a
Reviewed-on: https://boringssl-review.googlesource.com/5120
Reviewed-by: Adam Langley <agl@google.com>
2015-06-25 00:03:02 +00:00
Adam Langley
a59347eb4c RAND_set_rand_method takes a const parameter.
Change-Id: I37e7c00deeb74aa0b71ee0d3a242d33d4d413cf0
2015-06-24 17:02:15 -07:00
Matt Braithwaite
3e5e99d834 Dummy |RAND_set_rand_method|, |RAND_egd|, and |RAND_SSLeay|.
Change-Id: Ide555c77748b4ba8106f69b037e5ff78d81a56dc
Reviewed-on: https://boringssl-review.googlesource.com/5220
Reviewed-by: Adam Langley <agl@google.com>
2015-06-24 23:53:29 +00:00
Matt Braithwaite
50365f25ba Restore |DES_ede3_cfb_encrypt| and |DES_ede3_cfb64_encrypt| from OpenSSL at ce7e647b.
Change-Id: I7ab7ea3cdabc697b2945a50c8d8f349d6b408848
Reviewed-on: https://boringssl-review.googlesource.com/5211
Reviewed-by: Adam Langley <agl@google.com>
2015-06-24 01:33:31 +00:00
Adam Langley
b3cda6565a Fix signed/unsigned warnings for MSVC.
c0fe12cd broke the Windows build because of signed/unsigned compares.

Change-Id: Ie63246a60d51a8ccab17d4e2af8d155ed31b7b0a
2015-06-23 15:46:00 -07:00
Matt Braithwaite
c0fe12cdf7 Restore |X509_REQ_print| and friends, from OpenSSL at ce7e647b.
Change-Id: Id388510834ac30b0dbccfef0b8276f57656f1dfd
Reviewed-on: https://boringssl-review.googlesource.com/5210
Reviewed-by: Adam Langley <agl@google.com>
2015-06-23 22:36:52 +00:00
Adam Langley
248abbd71f Add missing comma in .type pragma for rdrand code.
This tripped up some version of GCC or Clang.

Change-Id: I925423558f188ce39b65b2e2ecd01bf009fab071
2015-06-23 15:01:45 -07:00
Matt Braithwaite
4cd4edfc34 Restore |ERR_print_errors()|.
Change-Id: If289c4aa2804727d6c5e8386b5a2b559cf006415
Reviewed-on: https://boringssl-review.googlesource.com/5152
Reviewed-by: Adam Langley <agl@google.com>
2015-06-23 21:41:24 +00:00
Adam Langley
9eaf07d460 Emit #if guards for ARM assembly files.
This change causes the generated assembly files for ARM and AArch64 to
have #if guards for __arm__ and __aarch64__, respectively. Since
building on ARM is only supported for Linux, we only have to worry about
GCC/Clang's predefines.

Change-Id: I7198eab6230bcfc26257f0fb6a0cc3166df0bb29
Reviewed-on: https://boringssl-review.googlesource.com/5173
Reviewed-by: Adam Langley <agl@google.com>
2015-06-23 21:00:32 +00:00
Adam Langley
2cac3506fa Handle RDRAND failures.
I mistakenly believed that only RDSEED could fail. However, the Intel
manuals state that RDRAND can fail too.

I can't actually observe it failing, even with all cores running RDRAND in a
tight loop. In any case, the ChaCha20 masking means that it wouldn't be
a big deal anyway.

Still, this change tests the carry flag after RDRAND and the code falls
back to |CRYPTO_sysrand| if RDRAND has a hiccup. (The Intel manuals
suggest[1] calling RDRAND in a loop, ten times, before considering it to
have failed. But a single failure appears to be such a rare event that
the complexity in the asm code doesn't seem worth it.)

This change also adds an asm function to fill a buffer with random data.
Otherwise the overhead of calling |CRYPTO_rdrand|, and bouncing the data
in and out of memory starts to add up.

Thanks to W. Mark Kubacki, who may have reported this. (There's some
confusion in the bug report.)

Before:

Did 6148000 RNG (16 bytes) operations in 1000080us: 98.4 MB/s
Did 649000 RNG (256 bytes) operations in 1000281us: 166.1 MB/s
Did 22000 RNG (8192 bytes) operations in 1033538us: 174.4 MB/s

After:

Did 6573000 RNG (16 bytes) operations in 1000002us: 105.2 MB/s
Did 693000 RNG (256 bytes) operations in 1000127us: 177.4 MB/s
Did 24000 RNG (8192 bytes) operations in 1028466us: 191.2 MB/s

[1] Intel Reference Manual, section 7.3.17.1.

Change-Id: Iba7f82e844ebacef535472a31f2dd749aad1190a
Reviewed-on: https://boringssl-review.googlesource.com/5180
Reviewed-by: Adam Langley <agl@google.com>
2015-06-23 20:56:33 +00:00
Matt Braithwaite
e65886a520 dsa_pub_encode: Write out DSA parameters (p, q, g) in addition to key.
Change-Id: Id5ea49fc43aacfd1d348b2a230c9745484bed852
Reviewed-on: https://boringssl-review.googlesource.com/5174
Reviewed-by: Adam Langley <agl@google.com>
2015-06-22 23:58:26 +00:00
Adam Langley
8de7aef05e Add a GCM test with non-standard nonce length.
AES-GCM should have a 12-byte nonce. However, non-standard nonce sizes
are defined by NIST and, although they are a bad idea, people have used
them because they've confused an IV with an nonce and passed in a
16-byte nonce.

This change adds a test for this.

Change-Id: If1efa1aaa19f0119ad4cab9a02a6417c040f45b2
2015-06-18 17:35:59 -07:00
Matt Braithwaite
7e8f2baeb7 Restore implementation of |NETSCAPE_SPKI_verify|.
Change-Id: I42c185a47af7e96e000ec1704e046b33a8571d1e
Reviewed-on: https://boringssl-review.googlesource.com/5153
Reviewed-by: Adam Langley <agl@google.com>
2015-06-18 23:41:42 +00:00
Matt Braithwaite
979c87add8 pem_lib: make |cipher_by_name| recognize some more ciphers.
Change-Id: I3130eec5d902ad22d1af185556955ff806b05097
Reviewed-on: https://boringssl-review.googlesource.com/5150
Reviewed-by: Adam Langley <agl@google.com>
2015-06-18 23:04:46 +00:00
David Benjamin
7244fa46f7 Expose ECDSA_SIG_max_len to size a DER ECDSA-Sig-Value.
Also implement it without reference to crypto/asn1 or fake ASN1_INTEGERs and
add a test. Some platform crypto APIs only give back the key size, and not the
encoded signature length. No sense in implementing it twice.

BUG=347404,499653

Change-Id: I9aa27d52674375f8b036e57bb5850f091c9b25dd
Reviewed-on: https://boringssl-review.googlesource.com/5080
Reviewed-by: Adam Langley <agl@google.com>
2015-06-18 22:23:12 +00:00
David Benjamin
b0acb7743f Export pkcs1_prefixed_msg as RSA_add_pkcs1_prefix.
Platform crypto APIs for PKCS#1 RSA signatures vary between expecting the
caller to prepend the DigestInfo prefix (RSA_sign_raw) and prepending it
internally (RSA_sign). Currently, Chromium implements sign or sign_raw as
appropriate. To avoid needing both variants, the new asynchronous methods will
only expose the higher-level one, sign.

To satisfy ports which previously implemented sign_raw, expose the DigestInfo
prefix as a utility function.

BUG=347404

Change-Id: I04c397b5e9502b2942f6698ecf81662a3c9282e6
Reviewed-on: https://boringssl-review.googlesource.com/4940
Reviewed-by: Adam Langley <agl@google.com>
2015-06-16 19:09:45 +00:00
David Benjamin
d87021d246 Fix length checks in X509_cmp_time to avoid out-of-bounds reads.
Also tighten X509_cmp_time to reject more than three fractional
seconds in the time; and to reject trailing garbage after the offset.

CVE-2015-1789

(Imported from upstream's 9bc3665ac9e3c36f7762acd3691e1115d250b030)

Change-Id: I2091b2d1b691c177d58dc7960e2e7eb4c97b1f69
Reviewed-on: https://boringssl-review.googlesource.com/5124
Reviewed-by: Adam Langley <agl@google.com>
2015-06-16 19:07:15 +00:00
David Benjamin
184494dfcc Raise SIGTRAP rather than abort on failure.
If gdb is attached, it's convenient to be able to continue running.

Change-Id: I3bbb2634d05a08f6bad5425f71da2210dbb80cfe
Reviewed-on: https://boringssl-review.googlesource.com/5125
Reviewed-by: Adam Langley <agl@google.com>
2015-06-16 18:25:30 +00:00
David Benjamin
fd67aa8c95 Add SSL_SESSION_from_bytes.
Mirrors SSL_SESSION_to_bytes. It avoids having to deal with object-reuse, the
non-size_t length parameter, and trailing data. Both it and the object-reuse
variant back onto an unexposed SSL_SESSION_parse which reads a CBS.

Note that this changes the object reuse story slightly. It's now merely an
optional output pointer that frees its old contents. No d2i_SSL_SESSION
consumer in Google that's built does reuse, much less reuse with the assumption
that the top-level object won't be overridden.

Change-Id: I5cb8522f96909bb222cab0f342423f2dd7814282
Reviewed-on: https://boringssl-review.googlesource.com/5121
Reviewed-by: Adam Langley <agl@google.com>
2015-06-16 18:12:39 +00:00
Adam Langley
a89fac585f Rename tabtest.c and v3nametest.c
The binaries for these already have underscores in, best to have the
source files match.

Change-Id: I32a419f32ec7786fe2537d061eb0706a7bc73f4a
Reviewed-on: https://boringssl-review.googlesource.com/5101
Reviewed-by: Adam Langley <agl@google.com>
2015-06-16 18:07:27 +00:00
David Benjamin
2b2b0f909d Set errno to ENOMEM when simulating a malloc failure.
Per malloc(3):

    The  UNIX  98  standard requires malloc(), calloc(), and realloc() to set
    errno to ENOMEM upon failure.  Glibc assumes that this is done (and the
    glibc versions of these routines do this); if you use a private malloc
    implementation that does not set errno, then certain library routines may
    fail without having a reason in errno.

Notably, thread_test otherwise fails an assertion deep in glibc.

Change-Id: Ia2c0ab306987476e7d6570d4bbf04a2641398925
Reviewed-on: https://boringssl-review.googlesource.com/5111
Reviewed-by: Adam Langley <agl@google.com>
2015-06-15 17:53:08 +00:00
David Benjamin
1c703cb0c1 Check for BN_copy failures.
BN_copy can fail on malloc failure. The case in crypto/rsa was causing the
malloc tests in all_tests.go to infinite loop.

Change-Id: Id5900512013fba9960444d78a8c056aa4314fb2d
Reviewed-on: https://boringssl-review.googlesource.com/5110
Reviewed-by: Adam Langley <agl@google.com>
2015-06-15 17:52:40 +00:00
Adam Langley
2b23eaa478 Use the correct case for Windows headers.
When cross-compiling for Windows on a Linux system, the filesystem is
case sensitive and so #includes with uppercase characters cause errors.

Change-Id: I6fe6d677887ce84ba8b2c3136cf2c70998d96e81
Reviewed-on: https://boringssl-review.googlesource.com/5060
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2015-06-09 21:38:04 +00:00
David Benjamin
24f346d77b Limit the number of warning alerts silently consumed.
Per review comments on
https://boringssl-review.googlesource.com/#/c/4112/.

Change-Id: I82cacf67c6882e64f6637015ac41945522699797
Reviewed-on: https://boringssl-review.googlesource.com/5041
Reviewed-by: Adam Langley <agl@google.com>
2015-06-08 22:16:14 +00:00
David Benjamin
c7a3a14872 Convert rsa_test to C++.
In doing so, check for malloc failures and use scopers as appropriate.
This should clear rsa_test for use with malloc tests. Also replace the
SetKey macro and exploded RSA keys with a DER RSAPrivateKey structure.
Much less tedious.

Change-Id: I3ce092ef67e7ac2af74f509abbdf84b7f2b6d45d
Reviewed-on: https://boringssl-review.googlesource.com/5043
Reviewed-by: Adam Langley <agl@google.com>
2015-06-08 22:11:20 +00:00
Adam Langley
521d4b805a Export |CBS_get_any_ber_asn1_element|.
We have need of it internally.

Change-Id: I564af468728b22245e8eab384ea7018b7e88cc86
Reviewed-on: https://boringssl-review.googlesource.com/5022
Reviewed-by: Matt Braithwaite <mab@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2015-06-05 21:56:42 +00:00
David Benjamin
1a3c23234c Fix build.
Mac wants a stdlib.h. Windows wants a void and doesn't like static const in
array declarations.

Change-Id: If1e8fb141e41200cf8a7348c6918c2f22465f5fe
Reviewed-on: https://boringssl-review.googlesource.com/5030
Reviewed-by: Adam Langley <agl@google.com>
2015-06-05 19:13:31 +00:00
Matt Braithwaite
1d0a056180 Explicitly cast |CHECK| result to |void| to avoid compiler complaint.
Change-Id: Ie7b376da1a157d144e9c4651722630dbf9c45436
Reviewed-on: https://boringssl-review.googlesource.com/5021
Reviewed-by: Adam Langley <agl@google.com>
2015-06-05 18:48:02 +00:00
Adam Langley
839b881c61 Multi-prime RSA support.
RSA with more than two primes is specified in
https://tools.ietf.org/html/rfc3447, although the idea goes back far
earier than that.

This change ports some of the changes in
http://rt.openssl.org/Ticket/Display.html?id=3477&user=guest&pass=guest
to BoringSSL—specifically those bits that are under an OpenSSL license.

Change-Id: I51e8e345e2148702b8ce12e00518f6ef4683d3e1
Reviewed-on: https://boringssl-review.googlesource.com/4870
Reviewed-by: Adam Langley <agl@google.com>
2015-06-05 18:39:44 +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
Adam Langley
ba5934b77f Tighten up EMS resumption behaviour.
The client and server both have to decide on behaviour when resuming a
session where the EMS state of the session doesn't match the EMS state
as exchanged in the handshake.

                        Original handshake
      |  No                                         Yes
------+--------------------------------------------------------------
      |
R     |  Server: ok [1]                     Server: abort [3]
e  No |  Client: ok [2]                     Client: abort [4]
s     |
u     |
m     |
e     |
  Yes |  Server: don't resume                   No problem
      |  Client: abort; server
      |    shouldn't have resumed

[1] Servers want to accept legacy clients. The draft[5] says that
resumptions SHOULD be rejected so that Triple-Handshake can't be done,
but we'll rather enforce that EMS was used when using tls-unique etc.

[2] The draft[5] says that even the initial handshake should be aborted
if the server doesn't support EMS, but we need to be able to talk to the
world.

[3] This is a very weird case where a client has regressed without
flushing the session cache. Hopefully we can be strict and reject these.

[4] This can happen when a server-farm shares a session cache but
frontends are not all updated at once. If Chrome is strict here then
hopefully we can prevent any servers from existing that will try to
resume an EMS session that they don't understand. OpenSSL appears to be
ok here: https://www.ietf.org/mail-archive/web/tls/current/msg16570.html

[5] https://tools.ietf.org/html/draft-ietf-tls-session-hash-05#section-5.2

BUG=492200

Change-Id: Ie1225a3960d49117b05eefa5a36263d8e556e467
Reviewed-on: https://boringssl-review.googlesource.com/4981
Reviewed-by: Adam Langley <agl@google.com>
2015-06-03 22:05:50 +00:00