Commit Graph

168 Commits

Author SHA1 Message Date
David Benjamin
79d18bc4dd Add crypto/rsa-level RSA-PSS functions.
This allows us to implement RSA-PSS in the FIPS module without pulling
in EVP_PKEY. It also allows people to use RSA-PSS on an RSA*.
Empirically folks seem to use the low-level padding functions a lot,
which is unfortunate.

This allows us to remove a now redundant length check in p_rsa.c.

Change-Id: I5270e01c6999d462d378865db2b858103c335485
Reviewed-on: https://boringssl-review.googlesource.com/15825
Reviewed-by: Adam Langley <agl@google.com>
2017-05-02 20:30:24 +00:00
David Benjamin
05821b0ee3 Consistently check length in RSA_add_pkcs1_prefix.
We check the length for MD5+SHA1 but not the normal cases. Instead,
EVP_PKEY_sign externally checks the length (largely because the silly
RSA-PSS padding function forces it). We especially should be checking
the length for these because otherwise the prefix built into the ASN.1
prefix is wrong.

The primary motivation is to avoid putting EVP_PKEY inside the FIPS
module. This means all logic for supported algorithms should live in
crypto/rsa.

This requires fixing up the verify_recover logic and some tests,
including bcm.c's KAT bits.

(evp_tests.txt is now this odd mixture of EVP-level and RSA-level error
codes. A follow-up change will add new APIs for RSA-PSS which will allow
p_rsa.c to be trimmed down and make things consistent.)

Change-Id: I29158e9695b28e8632b06b449234a5dded35c3e7
Reviewed-on: https://boringssl-review.googlesource.com/15824
Reviewed-by: Adam Langley <agl@google.com>
2017-05-02 20:29:47 +00:00
Adam Langley
5c38c05b26 Move bn/ into crypto/fipsmodule/
Change-Id: I68aa4a740ee1c7f2a308a6536f408929f15b694c
Reviewed-on: https://boringssl-review.googlesource.com/15647
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
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2017-05-01 22:51:25 +00:00
Steven Valdez
b1ffe0b36a Add primality checking for RSA_check_fips.
This also fixes the comments regarding BN_prime_checks to match the
security level guarantees provided by BN_prime_checks.

Change-Id: I8032e88680bf51e8876e134b4253ed26c2072617
Reviewed-on: https://boringssl-review.googlesource.com/15304
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
2017-04-21 22:38:31 +00:00
Adam Langley
518ba0772b Switch constant-time functions to using |crypto_word_t|.
Using |size_t| was correct, except for NaCl, which is a 64-bit build
with 32-bit pointers. In that configuration, |size_t| is smaller than
the native word size.

This change adds |crypto_word_t|, an unsigned type with native size and
switches constant-time functions to using it.

Change-Id: Ib275127063d5edbb7c55d413132711b7c74206b0
Reviewed-on: https://boringssl-review.googlesource.com/15325
Reviewed-by: Adam Langley <agl@google.com>
2017-04-21 22:06:05 +00:00
David Benjamin
34a8aacb51 Remove remnants of multiprime RSA parsing.
Change-Id: Id6d0dc2a9766458bb08863111f509719ca8e5214
Reviewed-on: https://boringssl-review.googlesource.com/15369
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
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2017-04-21 17:49:46 +00:00
Adam Langley
a54ebffa76 Fix lower bound in e in FIPS RSA checking.
SP 800-89 5.3.3 references FIPS 186 for the bounds on e. I /think/
that's section B.3.1 which says:

  (b) The exponent e shall be an odd positive integer such that 2¹⁶ < e < 2²⁵⁶.

But that means that e has to be at least 17 bits. The check for
BN_is_odd ensures that 2¹⁶ itself is rejected.

Change-Id: Ib39f9d43032cbfe33317651c7b6eceb41b123291
Reviewed-on: https://boringssl-review.googlesource.com/15324
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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2017-04-20 20:43:52 +00:00
Steven Valdez
b15143fece Fix check_fips for public keys and synchronize the EC and RSA versions.
Change-Id: Ibebf787445578608845df8861d67cd1e65ed0b35
Reviewed-on: https://boringssl-review.googlesource.com/15004
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
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2017-04-13 17:33:40 +00:00
Steven Valdez
400d0b7b5e Add PWCT for RSA and ECDSA for FIPS 140-2.
Since only the consumers knows whether an EC key will be used for
ECDSA or ECDHE, it is part of the FIPS policy for the consumer to
check the validity of the generated key before signing with it.

Change-Id: Ie250f655c8fcb6a59cc7210def1e87eb958e9349
Reviewed-on: https://boringssl-review.googlesource.com/14745
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
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2017-04-13 17:00:43 +00:00
David Benjamin
82b2b8574f Unwind multiprime RSA support.
FIPS is not compatible with multiprime RSA. Any multiprime RSA private
keys will fail to parse after this change.

Change-Id: I8d969d668bf0be4f66c66a30e56f0e7f6795f3e9
Reviewed-on: https://boringssl-review.googlesource.com/14984
Reviewed-by: Adam Langley <agl@google.com>
2017-04-12 23:14:57 +00:00
David Benjamin
fb8b763e51 Align RSA key generation with FIPS 186-4.
FIPS prescribes a slightly different key generation algorithm than we
use. Specifically:

- Rather than using BN_RAND_TOP_TWO (so using 1.5 as an upper bound for
  sqrt(2)), it prescribes using sqrt(2) itself. To avoid unnecessary
  squaring, we do a comparison against a hard-coded approximation for
  sqrt(2) good enough for the largest FIPS key size. I went ahead and
  made it constant-time since it was easy, but all this is far from
  constant-time.

- FIPS requires a check that |p-q| is sufficiently large.

- FIPS requires a check that d is sufficiently large.

- BN_generate_prime_ex adds some delta to clear a table of prime
  numbers. FIPS does not specify any of that, so implement a separate
  routine here.

The primality test itself will be aligned in a follow-up. For now, it is
left unchanged, except that trial division is turned back on. That makes
things faster and is analogous the original algorithm's delta-munging
logic.

Change-Id: If32f0635bfb67a8c4740dedd7781d00647bbf60b
Reviewed-on: https://boringssl-review.googlesource.com/14948
Reviewed-by: Adam Langley <agl@google.com>
2017-04-12 23:14:39 +00:00
David Benjamin
b7ded430e4 Constrain RSA bit sizes.
The FIPS RSA generation algorithm is unkind to keys with funny bit
sizes. Odd numbers of bits are especially inconvenient, but the sqrt(2)
bound is much simpler if the key size is a multiple of 128 (thus giving
prime sizes a multiple of 64, so the sqrt(2) bound is easier to work
with).

Also impose a minimum RSA key size. 255-bit RSA is far too small as it
is and gives small enough primes that the p-q FIPS bound (2^(n/2-100))
starts risking underflow.

Change-Id: I4583c90b67385e53641ccee9b29044e79e94c920
Reviewed-on: https://boringssl-review.googlesource.com/14947
Reviewed-by: Adam Langley <agl@google.com>
2017-04-12 22:27:45 +00:00
David Benjamin
ddd5ba78a9 Remove redundant check in RSA_sign.
This is just some idle cleanup. The padding functions already must
handle size checks. Swap out the error code in the low-level portions to
keep that unchanged.

Also remove an old TODO(fork) about constant-time-ness. Signature
verification padding checks don't need to be constant time, and
decryption ones should be resolved now.

Change-Id: I20e7affdb7f2dce167a304afe707bfd537dd412a
Reviewed-on: https://boringssl-review.googlesource.com/14946
Reviewed-by: Adam Langley <agl@google.com>
2017-04-12 22:06:11 +00:00
Steven Valdez
d0b988219f Add RSA_check_fips to support public key validation checks.
Change-Id: I0e00f099a17d88f56b49970e612b0911afd9661e
Reviewed-on: https://boringssl-review.googlesource.com/14866
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
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2017-04-12 20:00:30 +00:00
David Benjamin
4a2cc28b8c Unwind RSA_generate_multi_prime_key.
Later CLs will unwind the rest of multiprime RSA support. Start with key
generation.

Change-Id: Id20473fd55cf32c27ea4a57f2d2ea11daaffedeb
Reviewed-on: https://boringssl-review.googlesource.com/14870
Reviewed-by: Adam Langley <agl@google.com>
2017-04-11 18:15:20 +00:00
David Benjamin
43780cbc37 Tidy up some repetitive code.
Change-Id: Ib5b22a342b603854495d7013bd9376a4f1e12bd6
Reviewed-on: https://boringssl-review.googlesource.com/14869
Reviewed-by: Adam Langley <agl@google.com>
2017-04-11 18:10:28 +00:00
Steven Valdez
c196680120 Add comment about ensuring no other data follows the hash value in PKCS #1
Change-Id: I92419b7d2d8ded8f4868588ad3c24b70ac7f7b1b
Reviewed-on: https://boringssl-review.googlesource.com/14864
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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2017-04-10 20:03:07 +00:00
David Benjamin
17eeb9820c Unwind the rest of EVP_PKEY_supports_digest.
This is a remnant of a previous iteration of the SSL client certificate
bridging logic in Chromium.

Change-Id: Ifa8e15cc970395f179e2f6db65c97a342af5498d
Reviewed-on: https://boringssl-review.googlesource.com/14444
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2017-03-30 16:28:25 +00:00
David Benjamin
b0ad3d74db Convert more RSA padding check functions to size_t.
BUG=22

Change-Id: I9f392eef44e83efb4b13931acb2a3c642cbf1f29
Reviewed-on: https://boringssl-review.googlesource.com/14308
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2017-03-30 16:19:45 +00:00
David Benjamin
43ea204db7 Convert RSA_padding_check_PKCS1_type_1 to size_t.
BUG=22

Change-Id: I5bfa543c261623d125e7a25cea905e3b90b0c014
Reviewed-on: https://boringssl-review.googlesource.com/14307
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2017-03-30 16:03:20 +00:00
David Benjamin
d1c0de6fe0 Add size_t variants of constant-time functions.
These will be used in follow-up commits. The _s names are taken from
upstream, to ease importing code. I've also promoted the CONSTTIME_*
macros from the test. None of them are really necessary except
~0u cannot substitute for CONSTTIME_TRUE_S on 64-bit platforms, so
having the macros seems safer.

Once everything is converted, I expect the unsigned versions can be
removed, so I've made the _8 and _int functions act on size_t rather
than unsigned. The users of these functions basically only believe that
array indices and bytes exist.

BUG=22

Change-Id: I987bfb0c708dc726a6f2afcb05b6619bbd600564
Reviewed-on: https://boringssl-review.googlesource.com/14306
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2017-03-30 15:38:43 +00:00
David Benjamin
f466cdb5e0 size_t the RSA padding add functions.
The padding check functions will need to tweak their calling conventions
and the constant-time helpers, so leaving those alone for now. These
were the easy ones.

BUG=22

Change-Id: Ia00e41e26a134de17d56be3def5820cb042794e1
Reviewed-on: https://boringssl-review.googlesource.com/14265
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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2017-03-25 21:59:49 +00:00
David Benjamin
c90ed1901d Tidy up error-handling around computing the hash in PSS.
EVP_DigestUpdate can tolerate zero length inputs. Also properly clean up
ctx in all codepaths.

Change-Id: I90889c6236f6bf74625ba9f967de36949a9a6f83
Reviewed-on: https://boringssl-review.googlesource.com/14327
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
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2017-03-23 15:07:08 +00:00
David Benjamin
fd67f61bb4 Fix bounds check in RSA_verify_PKCS1_PSS_mgf1 when sLen is -2.
(Imported from upstream's 04cf39207f94abf89b3964c7710f22f829a1a78f.)

The other half of the change was fixed earlier, but this logic was still
off. This code is kind of a mess and needs a rewrite, but import the
change to get it correct and sufficiently tested first.

(If we could take the sLen = -2 case away altogether, that would be
great...)

Change-Id: I5786e980f26648822633fc216315e8f77ed4d45b
Reviewed-on: https://boringssl-review.googlesource.com/14321
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
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2017-03-21 16:17:19 +00:00
David Benjamin
b91b9a8967 Convert rsa_test to GTest.
BUG=129

Change-Id: I603054193a20c2bcc3ac1724f9b29d6384d9f62a
Reviewed-on: https://boringssl-review.googlesource.com/13626
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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2017-02-16 22:23:16 +00:00
David Benjamin
0a211dfe91 Remove BN_FLG_CONSTTIME.
BN_FLG_CONSTTIME is a ridiculous API and easy to mess up
(CVE-2016-2178). Instead, code that needs a particular algorithm which
preserves secrecy of some arguemnt should call into that algorithm
directly.

This is never set outside the library and is finally unused within the
library! Credit for all this goes almost entirely to Brian Smith. I just
took care of the last bits.

Note there was one BN_FLG_CONSTTIME check that was still reachable, the
BN_mod_inverse in RSA key generation. However, it used the same code in
both cases for even moduli and φ(n) is even if n is not a power of two.
Traditionally, RSA keys are not powers of two, even though it would make
the modular reductions a lot easier.

When reviewing, check that I didn't remove a BN_FLG_CONSTTIME that led
to a BN_mod_exp(_mont) or BN_mod_inverse call (with the exception of the
RSA one mentioned above). They should all go to functions for the
algorithms themselves like BN_mod_exp_mont_consttime.

This CL shows the checks are a no-op for all our tests:
https://boringssl-review.googlesource.com/c/12927/

BUG=125

Change-Id: I19cbb375cc75aac202bd76b51ca098841d84f337
Reviewed-on: https://boringssl-review.googlesource.com/12926
Reviewed-by: Adam Langley <alangley@gmail.com>
2017-01-12 02:00:44 +00:00
David Benjamin
0b8dc30932 Don't use BN_mod_inverse for inverses mod p in RSA keygen.
Instead, use BN_mod_exp_mont_consttime of p - 2. This removes two more
call sites sensitive to BN_FLG_CONSTTIME. We're down to just that last
BN_mod_inverse modulo φ(n). (Sort of. It's actually not sensitive
because even mod inverses always hit the other codepath. Perhaps we
should just leave it alone.)

Note this comes with a slight behavior change. The BN_MONT_CTXs are
initialized a little earlier. If a caller calls RSA_generate_* and then
reaches into the struct to scrap all the fields on it, they'll get
confused. Before, they had to perform an operation on it to get
confused. This is a completely ridiculous thing to do.

Since we do this a lot, this introduces some convenience functions for
doing the Fermat's Little Theorem mod inverse and fixes a leak in the
DSA code should computing kinv hit a malloc error.

BUG=125

Change-Id: Iafcae2fc6fd379d161f015c90ff7050e2282e905
Reviewed-on: https://boringssl-review.googlesource.com/12925
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
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2017-01-04 13:56:11 +00:00
David Benjamin
17cf2cb1d2 Work around language and compiler bug in memcpy, etc.
Most C standard library functions are undefined if passed NULL, even
when the corresponding length is zero. This gives them (and, in turn,
all functions which call them) surprising behavior on empty arrays.
Some compilers will miscompile code due to this rule. See also
https://www.imperialviolet.org/2016/06/26/nonnull.html

Add OPENSSL_memcpy, etc., wrappers which avoid this problem.

BUG=23

Change-Id: I95f42b23e92945af0e681264fffaf578e7f8465e
Reviewed-on: https://boringssl-review.googlesource.com/12928
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2016-12-21 20:34:47 +00:00
Brian Smith
9f05de4ebb Remove the non-no_branch branch of BN_div.
Simplify the code, and in particular make |BN_div|, |BN_mod|, and
|BN_nnmod| insensitive to |BN_FLG_CONSTTIME|. This improves the
effectiveness of testing by reducing the number of branches that are
likely to go untested or less tested.

There is no performance-sensitive code that uses BN_div but doesn't
already use BN_FLG_CONSTTIME except RSA signature verification and
EC_GROUP creation. RSA signature verification, ECDH, and ECDSA
performance aren't significantly different with this change.

Change-Id: Ie34c4ce925b939150529400cc60e1f414c7676cd
Reviewed-on: https://boringssl-review.googlesource.com/9105
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2016-12-17 19:11:19 +00:00
Brian Smith
febf77190f Verify consistency of RSA keys after generation & parsing.
Call |RSA_check_key| after parsing an RSA private key in order to
verify that the key is consistent. This is consistent with ECC key
parsing, which does a similar key check.

Call |RSA_check_key| after key generation mostly as a way of
double-checking the key generation was done correctly. A similar check
was not added to |EC_KEY_generate| because |EC_KEY_generate| is used
for generating ephemeral ECDH keys, and the check would be too
expensive for that use.

Change-Id: I5759d0d101c00711bbc30f81a3759f8bff01427c
Reviewed-on: https://boringssl-review.googlesource.com/7522
Reviewed-by: Adam Langley <agl@google.com>
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2016-12-16 17:37:03 +00:00
David Benjamin
54091230cd Use C99 for size_t loops.
This was done just by grepping for 'size_t i;' and 'size_t j;'. I left
everything in crypto/x509 and friends alone.

There's some instances in gcm.c that are non-trivial and pulled into a
separate CL for ease of review.

Change-Id: I6515804e3097f7e90855f1e7610868ee87117223
Reviewed-on: https://boringssl-review.googlesource.com/10801
Reviewed-by: Adam Langley <agl@google.com>
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2016-09-12 19:44:24 +00:00
Matt Braithwaite
d17d74d73f Replace Scoped* heap types with bssl::UniquePtr.
Unlike the Scoped* types, bssl::UniquePtr is available to C++ users, and
offered for a large variety of types.  The 'extern "C++"' trick is used
to make the C++ bits digestible to C callers that wrap header files in
'extern "C"'.

Change-Id: Ifbca4c2997d6628e33028c7d7620c72aff0f862e
Reviewed-on: https://boringssl-review.googlesource.com/10521
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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2016-09-01 22:22:54 +00:00
David Benjamin
5a91503826 Add various 1.1.0 accessors.
This gets cURL building against both BoringSSL as it is and BoringSSL
with OPENSSL_VERSION_NUMBER set to 1.1.0.

BUG=91

Change-Id: I5be73b84df701fe76f3055b1239ae4704a931082
Reviewed-on: https://boringssl-review.googlesource.com/10180
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Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2016-08-10 16:52:15 +00:00
Brian Smith
2a389ace62 Clarify signed/unsigned math in RSA_padding_add_PKCS1_PSS_mgf1.
Use a separate |size_t| variable for all logic that happens after the
special casing of the negative values of the signed parameter, to
minimize the amount of mixed signed/unsigned math used.

Change-Id: I4aeb1ffce47f889f340f9583684910b0fb2ca7c7
Reviewed-on: https://boringssl-review.googlesource.com/9173
Reviewed-by: David Benjamin <davidben@google.com>
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2016-08-09 19:10:18 +00:00
Brian Smith
8585701b2e Clarify checking of emLen in RSA_padding_add_PKCS1_PSS_mgf1.
There is a comment "Note from a test above this value is guaranteed to
be non-negative". Reorganize the code to make it more clear that that
is actually the case, especially in the case where sLen == -1.

Change-Id: I09a3dd99458e34102c42d8d3a2f22c16c684c673
Reviewed-on: https://boringssl-review.googlesource.com/9172
Reviewed-by: David Benjamin <davidben@google.com>
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2016-08-09 18:22:07 +00:00
Brian Smith
783eaad039 Put |sLen| logic in one place in RSA_padding_add_PKCS1_PSS_mgf1.
This makes it easier to understand the |sLen|-related logic.

Change-Id: I98da4f4f7c82d5481544940407e6cc6a963f7e5b
Reviewed-on: https://boringssl-review.googlesource.com/9171
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Reviewed-by: David Benjamin <davidben@google.com>
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2016-08-08 23:27:50 +00:00
David Benjamin
9305a13252 Tidy up PKCS1_MGF1.
Fix non-standard variable names, return value convention, unsigned vs
size_t, etc. This also fixes one size_t truncation warning.

BUG=22

Change-Id: Ibe083db90e8dac45d64da9ead8f519dd2fea96ea
Reviewed-on: https://boringssl-review.googlesource.com/9133
Commit-Queue: David Benjamin <davidben@google.com>
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2016-08-05 18:59:22 +00:00
Brian Smith
7fcbfdbdf3 Calculate inverse in |BN_MONT_CTX_set| in constant time w.r.t. modulus.
Simplify the calculation of the Montgomery constants in
|BN_MONT_CTX_set|, making the inversion constant-time. It should also
be faster by avoiding any use of the |BIGNUM| API in favor of using
only 64-bit arithmetic.

Now it's obvious how it works. /s

Change-Id: I59a1e1c3631f426fbeabd0c752e0de44bcb5fd75
Reviewed-on: https://boringssl-review.googlesource.com/9031
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2016-08-02 16:26:44 +00:00
Brian Smith
ec3cb3adbc Add |BN_mod_inverse_blinded| and use it in RSA blinding.
Yo dawg I herd you like blinding so I put inversion blinding in your
RSA blinding so you can randomly mask your random mask.

This improves upon the current situation where we pretend that
|BN_mod_inverse_no_branch| is constant-time, and it avoids the need to
exert a lot of effort to make a actually-constant-time modular
inversion function just for RSA blinding.

Note that if the random number generator weren't working correctly then
the blinding of the inversion wouldn't be very effective, but in that
case the RSA blinding itself would probably be completely busted, so
we're not really losing anything by relying on blinding to blind the
blinding.

Change-Id: I771100f0ad8ed3c24e80dd859ec22463ef2a194f
Reviewed-on: https://boringssl-review.googlesource.com/8923
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2016-07-29 18:30:34 +00:00
Brian Smith
4edca0b308 Add BN_rand_range_ex and use internally.
There are many cases where we need |BN_rand_range| but with a minimum
value other than 0. |BN_rand_range_ex| provides that.

Change-Id: I564326c9206bf4e20a37414bdbce16a951c148ce
Reviewed-on: https://boringssl-review.googlesource.com/8921
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2016-07-29 16:09:26 +00:00
Brian Smith
7241ca5ce4 Avoid one |BN_mod_inverse| in |RSA_check_key|.
|BN_mod_inverse| is expensive and leaky. In this case, we can avoid
it completely by taking advantage of the fact that we already have
the two values that are supposed to be inverses of each other.

Change-Id: I2230b4166fb9d89c7445f9f7c045a4c9e4c377b3
Reviewed-on: https://boringssl-review.googlesource.com/8925
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2016-07-27 17:19:11 +00:00
Matt Braithwaite
1c256544dd RSA_marshal_private_key: add missing CBB_flush()
Change-Id: I2584bd86473be5b9d92a13b65dc78658a433a375
Reviewed-on: https://boringssl-review.googlesource.com/8737
Reviewed-by: David Benjamin <davidben@google.com>
2016-07-13 03:49:41 +00:00
Adam Langley
10f97f3bfc Revert "Move C++ helpers into |bssl| namespace."
This reverts commit 09feb0f3d9.

(In order to make WebRTC happy this also needs to be reverted.)
2016-07-12 08:09:33 -07:00
Adam Langley
d2b5af56cf Revert scoped_types.h change.
This reverts commits:
8d79ed6740
19fdcb5234
8d79ed6740

Because WebRTC (at least) includes our headers in an extern "C" block,
which precludes having any C++ in them.

Change-Id: Ia849f43795a40034cbd45b22ea680b51aab28b2d
2016-07-12 08:05:38 -07:00
Adam Langley
8c3c3135a2 Remove scoped_types.h.
This change scatters the contents of the two scoped_types.h files into
the headers for each of the areas of the code. The types are now in the
|bssl| namespace.

Change-Id: I802b8de68fba4786b6a0ac1bacd11d81d5842423
Reviewed-on: https://boringssl-review.googlesource.com/8731
Reviewed-by: Adam Langley <agl@google.com>
2016-07-11 23:08:27 +00:00
Adam Langley
09feb0f3d9 Move C++ helpers into |bssl| namespace.
We currently have the situation where the |tool| and |bssl_shim| code
includes scoped_types.h from crypto/test and ssl/test. That's weird and
shouldn't happen. Also, our C++ consumers might quite like to have
access to the scoped types.

Thus this change moves some of the template code to base.h and puts it
all in a |bssl| namespace to prepare for scattering these types into
their respective headers. In order that all the existing test code be
able to access these types, it's all moved into the same namespace.

Change-Id: I3207e29474dc5fcc344ace43119df26dae04eabb
Reviewed-on: https://boringssl-review.googlesource.com/8730
Reviewed-by: David Benjamin <davidben@google.com>
2016-07-11 23:04:52 +00:00
David Benjamin
29270dea85 Split unlock functions into read/write variants.
Windows SRWLOCK requires you call different functions here. Split
them up in preparation for switching Windows from CRITICAL_SECTION.

BUG=37

Change-Id: I7b5c6a98eab9ae5bb0734b805cfa1ff334918f35
Reviewed-on: https://boringssl-review.googlesource.com/8080
Reviewed-by: Adam Langley <agl@google.com>
2016-05-31 21:09:29 +00:00
Brian Smith
598e55a795 Do RSA blinding unless |e| is NULL and specifically requested not to.
Change-Id: I189db990df2a3cbf68f820a8f9f16142ccd7070f
Reviewed-on: https://boringssl-review.googlesource.com/7595
Reviewed-by: David Benjamin <davidben@google.com>
2016-05-04 23:14:08 +00:00
Brian Smith
86080c336f Verify RSA private key operation regardless of whether CRT is used.
Previously, the verification was only done when using the CRT method,
as the CRT method has been shown to be extremely sensitive to fault
attacks. However, there's no reason to avoid doing the verification
when the non-CRT method is used (performance-sensitive applications
should always be using the CRT-capable keys).

Previously, when we detected a fault (attack) through this verification,
libcrypto would fall back to the non-CRT method and assume that the
non-CRT method would give a correct result, despite having just
detecting corruption that is likely from an attack. Instead, just give
up, like NSS does.

Previously, the code tried to handle the case where the input was not
reduced mod rsa->n. This is (was) not possible, so avoid trying to
handle that. This simplifies the equality check and lets us use
|CRYPTO_memcmp|.

Change-Id: I78d1e55520a1c8c280cae2b7256e12ff6290507d
Reviewed-on: https://boringssl-review.googlesource.com/7582
Reviewed-by: David Benjamin <davidben@google.com>
2016-05-04 22:58:17 +00:00
Brian Smith
86361a3910 Require the public exponent to be available in RSA blinding.
Require the public exponent to be available unless
|RSA_FLAG_NO_BLINDING| is set on the key. Also, document this.

If the public exponent |e| is not available, then we could compute it
from |p|, |q|, and |d|. However, there's no reasonable situation in
which we'd have |p| or |q| but not |e|; either we have all the CRT
parameters, or we have (e, d, n), or we have only (d, n). The
calculation to compute |e| exposes the private key to risk of side
channel attacks.

Also, it was particularly wasteful to compute |e| for each
|BN_BLINDING| created, instead of just once before the first
|BN_BLINDING| was created.

|BN_BLINDING| now no longer needs to contain a duplicate copy of |e|,
so it is now more space-efficient.

Note that the condition |b->e != NULL| in |bn_blinding_update| was
always true since commit cbf56a5683.

Change-Id: Ic2fd6980e0d359dcd53772a7c31bdd0267e316b4
Reviewed-on: https://boringssl-review.googlesource.com/7594
Reviewed-by: David Benjamin <davidben@google.com>
2016-04-18 23:34:46 +00:00