One less to worry about.
Bug: 232
Change-Id: Ib7d38e18fee02590088d76363e17f774cfefa59b
Reviewed-on: https://boringssl-review.googlesource.com/25252
Reviewed-by: Adam Langley <agl@google.com>
Saves a bit of work, and we get a width sanity-check.
Bug: 232
Change-Id: I1c6bc376c9d8aaf60a078fdc39f35b6f44a688c6
Reviewed-on: https://boringssl-review.googlesource.com/25251
Reviewed-by: Adam Langley <agl@google.com>
Give a non-minimal modulus, there are two possible values of R we might
pick: 2^(BN_BITS2 * width) or 2^(BN_BITS2 * bn_minimal_width).
Potentially secret moduli would make the former attractive and things
might even work, but our only secret moduli (RSA) have public bit
widths. It's more cases to test and the usual BIGNUM invariant is that
widths do not affect numerical output.
Thus, settle on minimizing mont->N for now. With the top explicitly made
minimal, computing |lgBigR| is also a little simpler.
This CL also abstracts out the < R check in the RSA code, and implements
it in a width-agnostic way.
Bug: 232
Change-Id: I354643df30530db7866bb7820e34241d7614f3c2
Reviewed-on: https://boringssl-review.googlesource.com/25250
Reviewed-by: Adam Langley <agl@google.com>
These functions already require their inputs to be reduced mod N (or, in
some cases, bounded by R or N*R), so negative numbers are nonsense. The
code still attempted to account for them by working on the absolute
value and fiddling with the sign bit. (The output would be in range (-N,
N) instead of [0, N).)
This complicates relaxing bn_correct_top because bn_correct_top is also
used to prevent storing a negative zero. Instead, just reject negative
inputs.
Upgrade-Note: These functions are public API, so some callers may
notice. Code search suggests there is only one caller outside
BoringSSL, and it looks fine.
Bug: 232
Change-Id: Ieba3acbb36b0ff6b72b8ed2b14882ec9b88e4665
Reviewed-on: https://boringssl-review.googlesource.com/25249
Reviewed-by: Adam Langley <agl@google.com>
This matches bn_mod_mul_montgomery_small and removes a bit of
unnecessary stuttering.
Change-Id: Ife249c6e8754aef23c144dbfdea5daaf7ed9f48a
Reviewed-on: https://boringssl-review.googlesource.com/25248
Reviewed-by: Adam Langley <agl@google.com>
This cuts down on a duplicated place where we mess with bn->top. It also
also better abstracts away what determines the value of R.
(I ordered this wrong and rebasing will be annoying. Specifically, the
question is what happens if the modulus is non-minimal. In
https://boringssl-review.googlesource.com/c/boringssl/+/25250/, R will
be determined by the stored width of mont->N, so we want to use mont's
copy of the modulus. Though, one way or another, the important part is
that it's inside the Montgomery abstraction.)
Bug: 232
Change-Id: I74212e094c8a47f396b87982039e49048a130916
Reviewed-on: https://boringssl-review.googlesource.com/25247
Reviewed-by: Adam Langley <agl@google.com>
This is actually a bit more complicated (the mismatching widths cases
will never actually happen in RSA), but it's easier to think about and
removes more width-sensitive logic.
Bug: 232
Change-Id: I85fe6e706be1f7d14ffaf587958e930f47f85b3c
Reviewed-on: https://boringssl-review.googlesource.com/25246
Reviewed-by: Adam Langley <agl@google.com>
This makes it easier going to and from non-minimal BIGNUMs and words
without worrying about the widths which are ultimately to become less
friendly.
Bug: 232
Change-Id: Ia57cb29164c560b600573c27b112ad9375a86aad
Reviewed-on: https://boringssl-review.googlesource.com/25245
Reviewed-by: Adam Langley <agl@google.com>
Thanks to Andres Erbsen for extremely helpful suggestions on how finally
plug this long-standing hole!
OpenSSL BIGNUMs are currently minimal-width, which means they cannot be
constant-time. We'll need to either excise BIGNUM from RSA and EC or
somehow fix BIGNUM. EC_SCALAR and later EC_FELEM work will excise it
from EC, but RSA's BIGNUMs are more transparent. Teaching BIGNUM to
handle non-minimal word widths is probably simpler.
The main constraint is BIGNUM's large "calculator" API surface. One
could, in theory, do arbitrary math on RSA components, which means all
public functions must tolerate non-minimal inputs. This is also useful
for EC; https://boringssl-review.googlesource.com/c/boringssl/+/24445 is
silly.
As a first step, fix comparison-type functions that were assuming
minimal BIGNUMs. I've also added bn_resize_words, but it is testing-only
until the rest of the library is fixed.
bn->top is now a loose upper bound we carry around. It does not affect
numerical results, only performance and secrecy. This is a departure
from the original meaning, and compiler help in auditing everything is
nice, so the final change in this series will rename bn->top to
bn->width. Thus these new functions are named per "width", not "top".
Looking further ahead, how are output BIGNUM widths determined? There's
three notions of correctness here:
1. Do I compute the right answer for all widths?
2. Do I handle secret data in constant time?
3. Does my memory usage not balloon absurdly?
For (1), a BIGNUM function must give the same answer for all input
widths. BN_mod_add_quick may assume |a| < |m|, but |a| may still be
wider than |m| by way of leading zeres. The simplest approach is to
write code in a width-agnostic way and rely on functions to accept all
widths. Where functions need to look at bn->d, we'll a few helper
functions to smooth over funny widths.
For (2), (1) is little cumbersome. Consider constant-time modular
addition. A sane type system would guarantee input widths match. But C
is weak here, and bifurcating the internals is a lot of work. Thus, at
least for now, I do not propose we move RSA's internal computation out
of BIGNUM. (EC_SCALAR/EC_FELEM are valuable for EC because we get to
stack-allocate, curves were already specialized, and EC only has two
types with many operations on those types. None of these apply to RSA.
We've got numbers mod n, mod p, mod q, and their corresponding
exponents, each of which is used for basically one operation.)
Instead, constant-time BIGNUM functions will output non-minimal widths.
This is trivial for BN_bin2bn or modular arithmetic. But for BN_mul,
constant-time[*] would dictate r->top = a->top + b->top. A calculator
repeatedly multiplying by one would then run out of memory. Those we'll
split into a private BN_mul_fixed for crypto, leaving BN_mul for
calculators. BN_mul is just BN_mul_fixed followed by bn_correct_top.
[*] BN_mul is not constant-time for other reasons, but that will be
fixed separately.
Bug: 232
Change-Id: Ide2258ae8c09a9a41bb71d6777908d1c27917069
Reviewed-on: https://boringssl-review.googlesource.com/25244
Reviewed-by: Adam Langley <agl@google.com>
Having it in base.h pollutes the global namespace a bit and, in
particular, causes clang to give unhelpful suggestions in consuming
projects.
Change-Id: I6ca1a88bdd1701f0c49192a0df56ac0953c7067c
Reviewed-on: https://boringssl-review.googlesource.com/25464
Commit-Queue: Steven Valdez <svaldez@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Previously we required that the calls to TLS's AES-GCM use an
incrementing nonce. This change relaxes that requirement so that nonces
need only be strictly monotonic (i.e. values can now be skipped). This
still meets the uniqueness requirements of a nonce.
Change-Id: Ib649a58bb93bf4dc0e081de8a5971daefffe9c70
Reviewed-on: https://boringssl-review.googlesource.com/25384
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
(See also https://github.com/openssl/openssl/pull/5154.)
The exponent here is one of d, dmp1, or dmq1 for RSA. This value and its
bit length are both secret. The only public upper bound is the bit width
of the corresponding modulus (RSA n, p, and q, respectively).
Although BN_num_bits is constant-time (sort of; see bn_correct_top notes
in preceding patch), this does not fix the root problem, which is that
the windows are based on the minimal bit width, not the upper bound. We
could use BN_num_bits(m), but BN_mod_exp_mont_consttime is public API
and may be called with larger exponents. Instead, use all top*BN_BITS2
bits in the BIGNUM. This is still sensitive to the long-standing
bn_correct_top leak, but we need to fix that regardless.
This may cause us to do a handful of extra multiplications for RSA keys
which are just above a whole number of words, but that is not a standard
RSA key size.
Change-Id: I5e2f12b70c303b27c597a7e513b7bf7288f7b0e3
Reviewed-on: https://boringssl-review.googlesource.com/25185
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
The original comment was a little confusing. Also lowercase
CTR_DRBG_update to make our usual naming for static functions.
Bug: 227
Change-Id: I381c7ba12b788452d54520b7bc3b13bba8a59f2d
Reviewed-on: https://boringssl-review.googlesource.com/25204
Reviewed-by: Adam Langley <agl@google.com>
(The BN_num_bits_word implementation was originally written by Andy
Polyakov for OpenSSL. See also
https://github.com/openssl/openssl/pull/5154.)
BN_num_bits, by way of BN_num_bits_word, currently leaks the
most-significant word of its argument via branching and memory access
pattern.
BN_num_bits is called on RSA prime factors in various places. These have
public bit lengths, but all bits beyond the high bit are secret. This
fully resolves those cases.
There are a few places where BN_num_bits is called on an input where
the bit length is also secret. The two left in BoringSSL are:
- BN_mod_exp_mont_consttime calls it on the RSA private exponent.
- The timing "fix" to add the order to k in DSA.
This does *not* fully resolve those cases as we still only look at the
top word. Today, that is guaranteed to be non-zero, but only because of
the long-standing bn_correct_top timing leak. Once that is fixed (I hope
to have patches soon), a constant-time BN_num_bits on such inputs must
count bits on each word.
Instead, those cases should not call BN_num_bits at all. The former uses
the bit width to pick windows, but it should be using the maximum bit
width. The next patch will fix this. The latter is the same "fix" we
excised from ECDSA in a838f9dc7e. That
should be excised from DSA after the bn_correct_top bug is fixed.
Thanks to Dinghao Wu, Danfeng Zhang, Shuai Wang, Pei Wang, and Xiao Liu
for reporting this issue.
Change-Id: Idc3da518cc5ec18bd8688b95f959b15300a57c14
Reviewed-on: https://boringssl-review.googlesource.com/25184
Reviewed-by: Adam Langley <agl@google.com>
The EC_POINTs are still allocated (for now), but everything else fits on
the stack nicely, which saves a lot of fiddling with cleanup and
allocations.
Change-Id: Ib8480737ecc97e6b40b2c05f217cd8d3dc82cb72
Reviewed-on: https://boringssl-review.googlesource.com/25150
Reviewed-by: Adam Langley <agl@google.com>
This is to simplify clearing unnecessary mallocs out of ec_wNAF_mul, and
perhaps to use it in tuned variable-time multiplication functions.
Change-Id: Ic390d2e8e20d0ee50f3643830a582e94baebba95
Reviewed-on: https://boringssl-review.googlesource.com/25149
Reviewed-by: Adam Langley <agl@google.com>
This cuts out another total_num-length array and simplifies things.
Leading zeros at the front of the schedule don't do anything, so it's
easier to just produce a fixed-length one. (I'm also hoping to
ultimately reuse this function in //third_party/fiat/p256.c and get the
best of both worlds for ECDSA verification; tuned field arithmetic
operations, precomputed table, and variable-time multiply.)
Change-Id: I771f4ff7dcfdc3ee0eff8d9038d6dc9a0be3d4e0
Reviewed-on: https://boringssl-review.googlesource.com/25148
Reviewed-by: Adam Langley <agl@google.com>
Note this switches from walking BN_num_bits to the full bit length of
the scalar. But that can only cause it to add a few extra zeros to the
front of the schedule, which r_is_at_infinity will skip over.
Change-Id: I91e087c9c03505566b68f75fb37dfb53db467652
Reviewed-on: https://boringssl-review.googlesource.com/25147
Reviewed-by: Adam Langley <agl@google.com>
This appears to be pointless. Before, we would have a 50% chance of
doing an inversion at each non-zero bit but the first
(r_is_at_infinity), plus a 50% chance of doing an inversion at the end.
Now we would have a 50% chance of doing an inversion at each non-zero
bit. That's the same number of coin flips.
Change-Id: I8158fd48601cb041188826d4f68ac1a31a6fbbbc
Reviewed-on: https://boringssl-review.googlesource.com/25146
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
The optimization for wsize = 1 only kicks in for 19-bit primes. The
cases for b >= 800 and cannot happen due to EC_MAX_SCALAR_BYTES.
Change-Id: If5ca908563f027172cdf31c9a22342152fecd12f
Reviewed-on: https://boringssl-review.googlesource.com/25145
Reviewed-by: Adam Langley <agl@google.com>
Simplify things slightly. The probability of the scalar being small
enough to go down a window size is astronomically small. (2^-186 for
P-256 and 2^-84 for P-384.)
Change-Id: Ie879f0b06bcfd1e6e6e3bf3f54e0d7d6567525a4
Reviewed-on: https://boringssl-review.googlesource.com/25144
Reviewed-by: Adam Langley <agl@google.com>
Some non-FIPS consumers exclude bcm.c and build each fragment file
separately. This means non-FIPS code cannot live in bcm.c.
https://boringssl-review.googlesource.com/25044 made the self-test
function exist outside of FIPS code, so it needed to be moved into is
own file.
To avoid confusing generate_build_files.py, this can't be named
self_test.c, so I went with self_check.c.
Change-Id: I337b39b158bc50d6ca0a8ad1b6e15eb851095e1e
Reviewed-on: https://boringssl-review.googlesource.com/25124
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
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>
Change-Id: Ib067411d4cafe1838c2dc42fc8bfd9011490f45c
Reviewed-on: https://boringssl-review.googlesource.com/25064
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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This change adds |BORINGSSL_self_test|, which allows applications to run
the FIPS KAT tests on demand, even in non-FIPS builds.
Change-Id: I950b30a02ab030d5e05f2d86148beb4ee1b5929c
Reviewed-on: https://boringssl-review.googlesource.com/25044
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: David Benjamin <davidben@google.com>
NIAP requires that the TLS KDF be tested by CAVP so this change moves
the PRF into crypto/fipsmodule/tls and adds a test harness for it. Like
the KAS tests, this is only triggered when “-niap” is passed to
run_cavp.go.
Change-Id: Iaa4973d915853c8e367e6106d829e44fcf1b4ce5
Reviewed-on: https://boringssl-review.googlesource.com/24666
Reviewed-by: Adam Langley <agl@google.com>
The P-224 implementation was missing the optimization to avoid doing
extra work when asking for only one coordinate (ECDH and ECDSA both
involve an x-coordinate query). The P-256 implementation was missing the
optimization to do one less Montgomery reduction.
TODO - Benchmarks
Change-Id: I268d9c24737c6da9efaf1c73395b73dd97355de7
Reviewed-on: https://boringssl-review.googlesource.com/24690
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
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EC_POINT_set_affine_coordinates_GFp already rejects coordinates which
are out of range. There's no need to double-check.
Change-Id: Id1685355c555dda66d2a14125cb0083342f37e53
Reviewed-on: https://boringssl-review.googlesource.com/24688
Reviewed-by: Adam Langley <agl@google.com>
p224-64.c can just write straight into the EC_POINT, as the other files
do, which saves the mess around BN_CTX. It's also more correct.
ec_point_set_Jprojective_coordinates_GFp abstracts out field_encode, but
then we would want to abstract out field_decode too when reading.
That then allows us to inline ec_point_set_Jprojective_coordinates_GFp
into ec_GFp_simple_point_set_affine_coordinates and get rid of an
unnecessary tower of helper functions. Also we can use the precomputed
value of one rather than recompute it each time.
Change-Id: I8282dc66a4a437f5a3b6a1a59cc39be4cb71ccf9
Reviewed-on: https://boringssl-review.googlesource.com/24687
Reviewed-by: Adam Langley <agl@google.com>
All the messing around with field_mul and field_sqr does the same thing
as calling EC_GROUP_get_curve_GFp. This is in preparation for ultimately
moving the field elements to an EC_FELEM type.
Where we draw the BIGNUM / EC_FELEM line determines what EC_FELEM
operations we need. Since we don't care much about the performance of
this function, leave it in BIGNUM so we don't need an EC_FELEM
BN_mod_sqrt just yet. We can push it down later if we feel so inclined.
Change-Id: Iec07240d40828df6b7a29fd1f430e3b390d5f506
Reviewed-on: https://boringssl-review.googlesource.com/24686
Reviewed-by: Adam Langley <agl@google.com>
This is to simplify
https://boringssl-review.googlesource.com/c/boringssl/+/24445/.
Setting or changing an EC_KEY's group after the public or private keys
have been configured is quite awkward w.r.t. consistency checks. It
becomes additionally messy if we mean to store private keys as
EC_SCALARs (and avoid the BIGNUM timing leak), whose size is
curve-dependent.
Instead, require that callers configure the group before setting either
half of the keypair. Additionally, reject EC_KEY_set_group calls that
change the group. This will simplify clearing one more BIGNUM timing
leak.
Update-Note: This will break code which sets the group and key in a
weird order. I checked calls of EC_KEY_new and confirmed they all
set the group first. If I missed any, let me know.
Change-Id: Ie89f90a318b31b6b98f71138e5ff3de5323bc9a6
Reviewed-on: https://boringssl-review.googlesource.com/24425
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
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RSA_METHOD_FLAG_NO_CHECK is the same as our RSA_FLAG_OPAQUE. cURL uses
this to determine if it should call SSL_CTX_check_private_key.
Change-Id: Ie2953632346a31de346a4452f4eaad8435cf76e8
Reviewed-on: https://boringssl-review.googlesource.com/24245
Reviewed-by: Adam Langley <agl@google.com>
Update-Note: Some RSA_FLAG_* constants are gone. Code search says they
were unused, but they can be easily restored if this breaks anything.
Change-Id: I47f642af5af9f8d80972ca8da0a0c2bd271c20eb
Reviewed-on: https://boringssl-review.googlesource.com/24244
Reviewed-by: Adam Langley <agl@google.com>
The first step of RSA with the CRT optimization is to reduce our input
modulo p and q. We can do this in constant-time[*] with Montgomery
reduction. When p and q are the same size, Montgomery reduction's bounds
hold. We need two rounds of it because the first round gives us an
unwanted R^-1.
This does not appear to have a measurable impact on performance. Also
add a long TODO describing how to make the rest of the function
constant-time[*] which hopefully we'll get to later. RSA blinding should
protect us from it all, but make this constant-time anyway.
Since this and the follow-up work will special-case weird keys, add a
test that we don't break those unintentionally. (Though I am not above
breaking them intentionally someday...)
Thanks to Andres Erbsen for discussions on how to do this bit properly.
[*] Ignoring the pervasive bn_correct_top problem for the moment.
Change-Id: Ide099a9db8249cb6549be99c5f8791a39692ea81
Reviewed-on: https://boringssl-review.googlesource.com/24204
Reviewed-by: Adam Langley <agl@google.com>
ARMv8 kindly deprecated most of its IT instructions in Thumb mode.
These files are taken from upstream and are used on both ARMv7 and ARMv8
processors. Accordingly, silence the warnings by marking the file as
targetting ARMv7. In other files, they were accidentally silenced anyway
by way of the existing .arch lines.
This can be reproduced by building with the new NDK and passing
-DCMAKE_ASM_FLAGS=-march=armv8-a. Some of our downstream code ends up
passing that to the assembly.
Note this change does not attempt to arrange for ARMv8-A/T32 to get
code which honors the constraints. It only silences the warnings and
continues to give it the same ARMv7-A/Thumb-2 code that backwards
compatibility dictates it continue to run.
Bug: chromium:575886, b/63131949
Change-Id: I24ce0b695942eaac799347922b243353b43ad7df
Reviewed-on: https://boringssl-review.googlesource.com/24166
Reviewed-by: Adam Langley <agl@google.com>
This makes it difficult to build against the NDK's toolchain file. The
problem is __clang__ just means Clang is the frontend and implies
nothing about which assembler. When using as, it is fine. When using
clang-as on Linux, one needs a clang-as from this year.
The only places where we case about clang's integrated assembler are iOS
(where perlasm strips out .arch anyway) and build environments like
Chromium which have a regularly-updated clang. Thus we can remove this
now.
Bug: 39
Update-Note: Holler if this breaks the build. If it doesn't break the
build, you can probably remove any BORINGSSL_CLANG_SUPPORTS_DOT_ARCH
or explicit -march armv8-a+crypto lines in your BoringSSL build.
Change-Id: I21ce54b14c659830520c2f1d51c7bd13e0980c68
Reviewed-on: https://boringssl-review.googlesource.com/24124
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
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It actually works fine. I just forgot one of the typedefs last time.
This gives a roughly 2x improvement on P-256 in clang-cl +
OPENSSL_SMALL, the configuration used by Chrome.
Before:
Did 1302 ECDH P-256 operations in 1015000us (1282.8 ops/sec)
Did 4250 ECDSA P-256 signing operations in 1047000us (4059.2 ops/sec)
Did 1750 ECDSA P-256 verify operations in 1094000us (1599.6 ops/sec)
After:
Did 3250 ECDH P-256 operations in 1078000us (3014.8 ops/sec)
Did 8250 ECDSA P-256 signing operations in 1016000us (8120.1 ops/sec)
Did 3250 ECDSA P-256 verify operations in 1063000us (3057.4 ops/sec)
(These were taken on a VM, so the measurements are extremely noisy, but
this sort of improvement is visible regardless.)
Alas, we do need a little extra bit of fiddling because division does
not work (crbug.com/787617).
Bug: chromium:787617
Update-Note: This removes the MSan uint128_t workaround which does not
appear to be necessary anymore.
Change-Id: I8361314608521e5bdaf0e7eeae7a02c33f55c69f
Reviewed-on: https://boringssl-review.googlesource.com/23984
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
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The fiat-crypto-generated code uses the Montgomery form implementation
strategy, for both 32-bit and 64-bit code.
64-bit throughput seems slower, but the difference is smaller than noise between repetitions (-2%?)
32-bit throughput has decreased significantly for ECDH (-40%). I am
attributing this to the change from varibale-time scalar multiplication
to constant-time scalar multiplication. Due to the same bottleneck,
ECDSA verification still uses the old code (otherwise there would have
been a 60% throughput decrease). On the other hand, ECDSA signing
throughput has increased slightly (+10%), perhaps due to the use of a
precomputed table of multiples of the base point.
64-bit benchmarks (Google Cloud Haswell):
with this change:
Did 9126 ECDH P-256 operations in 1009572us (9039.5 ops/sec)
Did 23000 ECDSA P-256 signing operations in 1039832us (22119.0 ops/sec)
Did 8820 ECDSA P-256 verify operations in 1024242us (8611.2 ops/sec)
master (40e8c921ca):
Did 9340 ECDH P-256 operations in 1017975us (9175.1 ops/sec)
Did 23000 ECDSA P-256 signing operations in 1039820us (22119.2 ops/sec)
Did 8688 ECDSA P-256 verify operations in 1021108us (8508.4 ops/sec)
benchmarks on ARMv7 (LG Nexus 4):
with this change:
Did 150 ECDH P-256 operations in 1029726us (145.7 ops/sec)
Did 506 ECDSA P-256 signing operations in 1065192us (475.0 ops/sec)
Did 363 ECDSA P-256 verify operations in 1033298us (351.3 ops/sec)
master (2fce1beda0):
Did 245 ECDH P-256 operations in 1017518us (240.8 ops/sec)
Did 473 ECDSA P-256 signing operations in 1086281us (435.4 ops/sec)
Did 360 ECDSA P-256 verify operations in 1003846us (358.6 ops/sec)
64-bit tables converted as follows:
import re, sys, math
p = 2**256 - 2**224 + 2**192 + 2**96 - 1
R = 2**256
def convert(t):
x0, s1, x1, s2, x2, s3, x3 = t.groups()
v = int(x0, 0) + 2**64 * (int(x1, 0) + 2**64*(int(x2,0) + 2**64*(int(x3, 0)) ))
w = v*R%p
y0 = hex(w%(2**64))
y1 = hex((w>>64)%(2**64))
y2 = hex((w>>(2*64))%(2**64))
y3 = hex((w>>(3*64))%(2**64))
ww = int(y0, 0) + 2**64 * (int(y1, 0) + 2**64*(int(y2,0) + 2**64*(int(y3, 0)) ))
if ww != v*R%p:
print(x0,x1,x2,x3)
print(hex(v))
print(y0,y1,y2,y3)
print(hex(w))
print(hex(ww))
assert 0
return '{'+y0+s1+y1+s2+y2+s3+y3+'}'
fe_re = re.compile('{'+r'(\s*,\s*)'.join(r'(\d+|0x[abcdefABCDEF0123456789]+)' for i in range(4)) + '}')
print (re.sub(fe_re, convert, sys.stdin.read()).rstrip('\n'))
32-bit tables converted from 64-bit tables
Change-Id: I52d6e5504fcb6ca2e8b0ee13727f4500c80c1799
Reviewed-on: https://boringssl-review.googlesource.com/23244
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Along the way, this allows us to tidy up the invariants associated with
EC_SCALAR. They were fuzzy around ec_point_mul_scalar and some
computations starting from the digest in ECDSA. The latter I've put into
the type system with EC_LOOSE_SCALAR.
As for the former, Andres points out that particular EC implementations
are only good for scalars within a certain range, otherwise you may need
extra work to avoid the doubling case. To simplify curve
implementations, we reduce them fully rather than do the looser bit size
check, so they can have the stronger precondition to work with.
Change-Id: Iff9a0404f89adf8f7f914f8e8246c9f3136453f1
Reviewed-on: https://boringssl-review.googlesource.com/23664
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Credit to OSS-Fuzz for finding this.
CVE-2017-3738
(Imported from upstream's 5630661aecbea5fe3c4740f5fea744a1f07a6253 and
77d75993651b63e872244a3256e37967bb3c3e9e.)
Confirmed with Intel SDE that the fix makes the test vector pass and
that, without the fix, the test vector does not. (Well, we knew the
latter already, since it was our test vector.)
Change-Id: I167aa3407ddab3b434bacbd18e099c55aa40ac4c
Reviewed-on: https://boringssl-review.googlesource.com/23884
Reviewed-by: Adam Langley <agl@google.com>
We check that the private key is less than the order, but we forgot the
other end.
Update-Note: It's possible some caller was relying on this, but since
that function already checked the other half of the range, I'm
expecting this to be a no-op change.
Change-Id: I4a53357d7737735b3cfbe97d379c8ca4eca5d5ac
Reviewed-on: https://boringssl-review.googlesource.com/23665
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
Change-Id: Id8b69bb6103dd938f4c6d0d2ec24f3d50ba5513c
Update-Note: fixes b/70034392
Reviewed-on: https://boringssl-review.googlesource.com/23744
Commit-Queue: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Rejecting values where we'd previous called BN_nnmod may have been
overly ambitious. In the long run, all the supported ECC APIs (ECDSA*,
ECDH_compute_key, and probably some additional new ECDH API) will be
using the EC_SCALAR version anyway, so this doesn't really matter.
Change-Id: I79cd4015f2d6daf213e4413caa2a497608976f93
Reviewed-on: https://boringssl-review.googlesource.com/23584
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
This is only a hair faster than the signing change, but still something.
I kept the call to BN_mod_inverse_odd as that appears to be faster
(constant time is not a concern for verification).
Before:
Did 22855 ECDSA P-224 verify operations in 3015099us (7580.2 ops/sec)
Did 21276 ECDSA P-256 verify operations in 3083284us (6900.4 ops/sec)
Did 2635 ECDSA P-384 verify operations in 3032582us (868.9 ops/sec)
Did 1240 ECDSA P-521 verify operations in 3068631us (404.1 ops/sec)
After:
Did 23310 ECDSA P-224 verify operations in 3056226us (7627.1 ops/sec)
Did 21210 ECDSA P-256 verify operations in 3035765us (6986.7 ops/sec)
Did 2666 ECDSA P-384 verify operations in 3023592us (881.7 ops/sec)
Did 1209 ECDSA P-521 verify operations in 3054040us (395.9 ops/sec)
Change-Id: Iec995b1a959dbc83049d0f05bdc525c14a95c28e
Reviewed-on: https://boringssl-review.googlesource.com/23077
Reviewed-by: Adam Langley <agl@google.com>
Hasse's theorem implies at most one subtraction is necessary. This is
still using BIGNUM for now because field elements
(EC_POINT_get_affine_coordinates_GFp) are BIGNUMs.
This gives an additional 2% speedup for signing.
Before:
Did 16000 ECDSA P-224 signing operations in 1064799us (15026.3 ops/sec)
Did 19000 ECDSA P-256 signing operations in 1007839us (18852.2 ops/sec)
Did 1078 ECDSA P-384 signing operations in 1079413us (998.7 ops/sec)
Did 484 ECDSA P-521 signing operations in 1083616us (446.7 ops/sec)
After:
Did 16000 ECDSA P-224 signing operations in 1054918us (15167.1 ops/sec)
Did 20000 ECDSA P-256 signing operations in 1037338us (19280.1 ops/sec)
Did 1045 ECDSA P-384 signing operations in 1049073us (996.1 ops/sec)
Did 484 ECDSA P-521 signing operations in 1085492us (445.9 ops/sec)
Change-Id: I2bfe214f968eca7a8e317928c0f3daf1a14bca90
Reviewed-on: https://boringssl-review.googlesource.com/23076
Reviewed-by: Adam Langley <agl@google.com>
None of the asymmetric crypto we inherented from OpenSSL is
constant-time because of BIGNUM. BIGNUM chops leading zeros off the
front of everything, so we end up leaking information about the first
word, in theory. BIGNUM functions additionally tend to take the full
range of inputs and then call into BN_nnmod at various points.
All our secret values should be acted on in constant-time, but k in
ECDSA is a particularly sensitive value. So, ecdsa_sign_setup, in an
attempt to mitigate the BIGNUM leaks, would add a couple copies of the
order.
This does not work at all. k is used to compute two values: k^-1 and kG.
The first operation when computing k^-1 is to call BN_nnmod if k is out
of range. The entry point to our tuned constant-time curve
implementations is to call BN_nnmod if the scalar has too many bits,
which this causes. The result is both corrections are immediately undone
but cause us to do more variable-time work in the meantime.
Replace all these computations around k with the word-based functions
added in the various preceding CLs. In doing so, replace the BN_mod_mul
calls (which internally call BN_nnmod) with Montgomery reduction. We can
avoid taking k^-1 out of Montgomery form, which combines nicely with
Brian Smith's trick in 3426d10119. Along
the way, we avoid some unnecessary mallocs.
BIGNUM still affects the private key itself, as well as the EC_POINTs.
But this should hopefully be much better now. Also it's 10% faster:
Before:
Did 15000 ECDSA P-224 signing operations in 1069117us (14030.3 ops/sec)
Did 18000 ECDSA P-256 signing operations in 1053908us (17079.3 ops/sec)
Did 1078 ECDSA P-384 signing operations in 1087853us (990.9 ops/sec)
Did 473 ECDSA P-521 signing operations in 1069835us (442.1 ops/sec)
After:
Did 16000 ECDSA P-224 signing operations in 1064799us (15026.3 ops/sec)
Did 19000 ECDSA P-256 signing operations in 1007839us (18852.2 ops/sec)
Did 1078 ECDSA P-384 signing operations in 1079413us (998.7 ops/sec)
Did 484 ECDSA P-521 signing operations in 1083616us (446.7 ops/sec)
Change-Id: I2a25e90fc99dac13c0616d0ea45e125a4bd8cca1
Reviewed-on: https://boringssl-review.googlesource.com/23075
Reviewed-by: Adam Langley <agl@google.com>
Imported from upstream's a78324d95bd4568ce2c3b34bfa1d6f14cddf92ef. I
think the "regression" part of that change is some tweak to BN_usub and
I guess the bn_*_words was to compensate for it, but we may as well
import it. Apparently the loop instruction is terrible.
Before:
Did 39871000 bn_add_words operations in 1000002us (39870920.3 ops/sec)
Did 38621750 bn_sub_words operations in 1000001us (38621711.4 ops/sec)
After:
Did 64012000 bn_add_words operations in 1000007us (64011551.9 ops/sec)
Did 81792250 bn_sub_words operations in 1000002us (81792086.4 ops/sec)
loop sets no flags (even doing the comparison to zero without ZF) while
dec sets all flags but CF, so Andres and I are assuming that because
this prevents Intel from microcoding it to dec/jnz, they otherwise can't
be bothered to add more circuitry since every compiler has internalized
by now to never use loop.
Change-Id: I3927cd1c7b707841bbe9963e3d4afd7ba9bd9b36
Reviewed-on: https://boringssl-review.googlesource.com/23344
Reviewed-by: Adam Langley <agl@google.com>
These allow precomputation of k, but bypass our nonce hardening and also
make it harder to excise BIGNUM. As a bonus, ECDSATest.SignTestVectors
is now actually covering the k^-1 and r computations.
Change-Id: I4c71dae162874a88a182387ac43999be9559ddd7
Reviewed-on: https://boringssl-review.googlesource.com/23074
Reviewed-by: Adam Langley <agl@google.com>
wpa_supplicant appear to be using these.
Change-Id: I1f220cae69162901bcd9452e8daf67379c5e276c
Reviewed-on: https://boringssl-review.googlesource.com/23324
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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