Change-Id: I92419b7d2d8ded8f4868588ad3c24b70ac7f7b1b
Reviewed-on: https://boringssl-review.googlesource.com/14864
Reviewed-by: David Benjamin <davidben@google.com>
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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>
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>
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>
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>
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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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>
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(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>
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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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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>
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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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>
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>
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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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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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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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
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
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>
Commit-Queue: David Benjamin <davidben@google.com>
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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>
Commit-Queue: David Benjamin <davidben@google.com>
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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>
Commit-Queue: David Benjamin <davidben@google.com>
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>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
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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>
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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>
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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>
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|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>
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This reverts commits:
8d79ed674019fdcb52348d79ed6740
Because WebRTC (at least) includes our headers in an extern "C" block,
which precludes having any C++ in them.
Change-Id: Ia849f43795a40034cbd45b22ea680b51aab28b2d
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>
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>
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>
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>
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>
This reduces the chance of double-frees.
BUG=10
Change-Id: I11a240e2ea5572effeddc05acb94db08c54a2e0b
Reviewed-on: https://boringssl-review.googlesource.com/7583
Reviewed-by: David Benjamin <davidben@google.com>
When |rsa->e == NULL| we cannot verify the result, so using the CRT
would leave the key too vulnerable to fault attacks.
Change-Id: I154622cf6205ba4d5fb219143db6072a787c2d1f
Reviewed-on: https://boringssl-review.googlesource.com/7581
Reviewed-by: David Benjamin <davidben@google.com>
|CRYPTO_memcmp| isn't necessary because there is no secret data being
acted on here.
Change-Id: Ib678d5d4fc16958aca409a93df139bdff8cb73fb
Reviewed-on: https://boringssl-review.googlesource.com/7465
Reviewed-by: David Benjamin <davidben@google.com>
Use the common pattern of returning early instead of |goto err;| when
there's no cleanup to do yet. Also, move the error checking of
|BN_CTX_get| failure closer to the the calls to |BN_CTX_get|. Avoid
calling |OPENSSL_cleanse| on public data. Clarify when/why |buf| is not
freed.
Change-Id: I9df833db7eb7041c5af9349c461297372b988f98
Reviewed-on: https://boringssl-review.googlesource.com/7464
Reviewed-by: David Benjamin <davidben@google.com>
The same check is already done in |RSA_verify_raw|, so |RSA_verify|
doesn't need to do it.
Also, move the |RSA_verify_raw| check earlier.
Change-Id: I15f7db0aad386c0f764bba53e77dfc46574f7635
Reviewed-on: https://boringssl-review.googlesource.com/7463
Reviewed-by: David Benjamin <davidben@google.com>
We do not need to support engine-provided verification methods.
Change-Id: Iaad8369d403082b728c831167cc386fdcabfb067
Reviewed-on: https://boringssl-review.googlesource.com/7311
Reviewed-by: David Benjamin <davidben@google.com>
A lot of consumers of obj.h only want the NID values. Others didn't need
it at all. This also removes some OBJ_nid2sn and OBJ_nid2ln calls in EVP
error paths which isn't worth pulling a large table in for.
BUG=chromium:499653
Change-Id: Id6dff578f993012e35b740a13b8e4f9c2edc0744
Reviewed-on: https://boringssl-review.googlesource.com/7563
Reviewed-by: David Benjamin <davidben@google.com>
The documentation in |RSA_METHOD| says that the |ctx| parameter to
|mod_exp| can be NULL, however the default implementation doesn't
handle that case. That wouldn't matter since internally it is always
called with a non-NULL |ctx| and it is static, but an external
application could get a pointer to |mod_exp| by extracting it from
the default |RSA_METHOD|. That's unlikely, but making that impossible
reduces the chances that future refactorings will cause unexpected
trouble.
Change-Id: Ie0e35e9f107551a16b49c1eb91d0d3386604e594
Reviewed-on: https://boringssl-review.googlesource.com/7580
Reviewed-by: David Benjamin <davidben@google.com>
|BN_mod_mul_montgomery| has better constant-time behavior (usually)
than |BN_mod_mul| and |BN_mod_sqr| and on platforms where we have
assembly language optimizations (when |OPENSSL_BN_ASM_MONT| is set in
crypto/bn/montgomery.c) it is faster. While doing so, reorder and
rename the |BN_MONT_CTX| parameters of the blinding functions to match
the order normally used in Montgomery math functions.
As a bonus, remove a redundant copy of the RSA public modulus from the
|BN_BLINDING| structure, which reduces memory usage.
Change-Id: I70597e40246429c7964947a1dc46d0d81c7530ef
Reviewed-on: https://boringssl-review.googlesource.com/7524
Reviewed-by: David Benjamin <davidben@google.com>
Change-Id: I0effe99d244c4ccdbb0e34db6e01a59c9463cb15
Reviewed-on: https://boringssl-review.googlesource.com/7572
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Conscrypt, thanks to Java's RSAPrivateKeySpec API, must be able to use RSA keys
with only modulus and exponent. This is kind of silly and breaks the blinding
code so they, both in OpenSSL and BoringSSL, had to explicitly turn blinding
off.
Add a test for this as we're otherwise sure to break it on accident.
We may wish to avoid the silly rsa->flags modification, I'm not sure. For now,
keep the requirement in so other consumers do not accidentally rely on this.
(Also add a few missing ERR_clear_error calls. Functions which are expected to
fail should be followed by an ERR_clear_error so later unexpected failures
don't get confused.)
BUG=boringssl:12
Change-Id: I674349821f1f59292b8edd085f21dc37e8bcaa75
Reviewed-on: https://boringssl-review.googlesource.com/7560
Reviewed-by: David Benjamin <davidben@google.com>
In |bn_blinding_update| the condition |b->e != NULL| would never be
true (probably), but the test made reasoning about the correctness of
the code confusing. That confusion was amplified by the circuitous and
unusual way in which |BN_BLINDING|s are constructed. Clarify all this
by simplifying the construction of |BN_BLINDING|s, making it more like
the construction of other structures.
Also, make counter unsigned as it is no longer ever negative.
Change-Id: I6161dcfeae19a80c780ccc6762314079fca1088b
Reviewed-on: https://boringssl-review.googlesource.com/7530
Reviewed-by: David Benjamin <davidben@google.com>
Simplify the code by always caching Montgomery contexts in the RSA
structure, regardless of the |RSA_FLAG_CACHE_PUBLIC| and
|RSA_FLAG_CACHE_PRIVATE| flags. Deprecate those flags.
Now that we do this no more than once per key per RSA exponent, the
private key exponents better because the initialization of the
Montgomery contexts isn't perfectly side-channel protected.
Change-Id: I4fbcfec0f2f628930bfeb811285b0ae3d103ac5e
Reviewed-on: https://boringssl-review.googlesource.com/7521
Reviewed-by: David Benjamin <davidben@google.com>
The fields of the |bn_blinding_st| are not updated atomically.
Consequently, one field (|A| or |Ai|) might get updated while the
other field (|Ai| or |A|) doesn't get updated, if an error occurs in
the middle of updating. Deal with this by reseting the counter so that
|A| and |Ai| will both get recreated the next time the blinding is
used.
Fix a separate but related issue by resetting the counter to zero after
calling |bn_blinding_create_param| only if |bn_blinding_create_param|
succeeded. Previously, regardless of whether an error occured in
|bn_blinding_create_param|, |b->counter| would get reset to zero. The
consequence of this was that potentially-bad blinding values would get
used 32 times instead of (32 - |b->counter|) times.
Change-Id: I236cdb6120870ef06cba129ed86619f593cbcf3d
Reviewed-on: https://boringssl-review.googlesource.com/7520
Reviewed-by: David Benjamin <davidben@google.com>
As far as I can tell, this is the last place within libcrypto where
this type of check is missing.
Change-Id: I3d09676abab8c9f6c4e87214019a382ec2ba90ee
Reviewed-on: https://boringssl-review.googlesource.com/7519
Reviewed-by: David Benjamin <davidben@google.com>
