This commit improves the performance of ECDSA signature verification
(over NIST P-256 curve) for x86 platforms. The speedup is by a factor of 1.15x.
It does so by:
1) Leveraging the fact that the verification does not need
to run in constant time. To this end, we implemented:
a) the function ecp_nistz256_points_mul_public in a similar way to
the current ecp_nistz256_points_mul function by removing its constant
time features.
b) the Binary Extended Euclidean Algorithm (BEEU) in x86 assembly to
replace the current modular inverse function used for the inversion.
2) The last step in the ECDSA_verify function compares the (x) affine
coordinate with the signature (r) value. Converting x from the Jacobian's
representation to the affine coordinate requires to perform one inversions
(x_affine = x * z^(-2)). We save this inversion and speed up the computations
by instead bringing r to x (r_jacobian = r*z^2) which is faster.
The measured results are:
Before (on a Kaby Lake desktop with gcc-5):
Did 26000 ECDSA P-224 signing operations in 1002372us (25938.5 ops/sec)
Did 11000 ECDSA P-224 verify operations in 1043821us (10538.2 ops/sec)
Did 55000 ECDSA P-256 signing operations in 1017560us (54050.9 ops/sec)
Did 17000 ECDSA P-256 verify operations in 1051280us (16170.8 ops/sec)
After (on a Kaby Lake desktop with gcc-5):
Did 27000 ECDSA P-224 signing operations in 1011287us (26698.7 ops/sec)
Did 11640 ECDSA P-224 verify operations in 1076698us (10810.8 ops/sec)
Did 55000 ECDSA P-256 signing operations in 1016880us (54087.0 ops/sec)
Did 20000 ECDSA P-256 verify operations in 1038736us (19254.2 ops/sec)
Before (on a Skylake server platform with gcc-5):
Did 25000 ECDSA P-224 signing operations in 1021651us (24470.2 ops/sec)
Did 10373 ECDSA P-224 verify operations in 1046563us (9911.5 ops/sec)
Did 50000 ECDSA P-256 signing operations in 1002774us (49861.7 ops/sec)
Did 15000 ECDSA P-256 verify operations in 1006471us (14903.6 ops/sec)
After (on a Skylake server platform with gcc-5):
Did 25000 ECDSA P-224 signing operations in 1020958us (24486.8 ops/sec)
Did 10373 ECDSA P-224 verify operations in 1046359us (9913.4 ops/sec)
Did 50000 ECDSA P-256 signing operations in 1003996us (49801.0 ops/sec)
Did 18000 ECDSA P-256 verify operations in 1021604us (17619.4 ops/sec)
Developers and authors:
***************************************************************************
Nir Drucker (1,2), Shay Gueron (1,2)
(1) Amazon Web Services Inc.
(2) University of Haifa, Israel
***************************************************************************
Change-Id: Idd42a7bc40626bce974ea000b61fdb5bad33851c
Reviewed-on: https://boringssl-review.googlesource.com/c/31304
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>
Reviewed-by: Adam Langley <agl@google.com>
cryptography.io wants things exposed out of EVP_get_cipherby* including,
sadly, ECB mode.
Change-Id: I9bac46f8ffad1a79d190cee3b0c0686bf540298e
Reviewed-on: https://boringssl-review.googlesource.com/28464
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>
EC_POINT is split into the existing public EC_POINT (where the caller is
sanity-checked about group mismatches) and the low-level EC_RAW_POINT
(which, like EC_FELEM and EC_SCALAR, assume that is your problem and is
a plain old struct). Having both EC_POINT and EC_RAW_POINT is a little
silly, but we're going to want different type signatures for functions
which return void anyway (my plan is to lift a non-BIGNUM
get_affine_coordinates up through the ECDSA and ECDH code), so I think
it's fine.
This wasn't strictly necessary, but wnaf.c is a lot tidier now. Perf is
a wash; once we get up to this layer, it's only 8 entries in the table
so not particularly interesting.
Bug: 239
Change-Id: I8ace749393d359f42649a5bb0734597bb7c07a2e
Reviewed-on: https://boringssl-review.googlesource.com/27706
Commit-Queue: David Benjamin <davidben@google.com>
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Reviewed-by: Adam Langley <agl@google.com>
This introduces EC_FELEM, which is analogous to EC_SCALAR. It is used
for EC_POINT's representation in the generic EC_METHOD, as well as
random operations on tuned EC_METHODs that still are implemented
genericly.
Unlike EC_SCALAR, EC_FELEM's exact representation is awkwardly specific
to the EC_METHOD, analogous to how the old values were BIGNUMs but may
or may not have been in Montgomery form. This is kind of a nuisance, but
no more than before. (If p224-64.c were easily convertable to Montgomery
form, we could say |EC_FELEM| is always in Montgomery form. If we
exposed the internal add and double implementations in each of the
curves, we could give |EC_POINT| an |EC_METHOD|-specific representation
and |EC_FELEM| is purely a |EC_GFp_mont_method| type. I'll leave this
for later.)
The generic add and doubling formulas are aligned with the formulas
proved in fiat-crypto. Those only applied to a = -3, so I've proved a
generic one in https://github.com/mit-plv/fiat-crypto/pull/356, in case
someone uses a custom curve. The new formulas are verified,
constant-time, and swap a multiply for a square. As expressed in
fiat-crypto they do use more temporaries, but this seems to be fine with
stack-allocated EC_FELEMs. (We can try to help the compiler later,
but benchamrks below suggest this isn't necessary.)
Unlike BIGNUM, EC_FELEM can be stack-allocated. It also captures the
bounds in the type system and, in particular, that the width is correct,
which will make it easier to select a point in constant-time in the
future. (Indeed the old code did not always have the correct width. Its
point formula involved halving and implemented this in variable time and
variable width.)
Before:
Did 77274 ECDH P-256 operations in 10046087us (7692.0 ops/sec)
Did 5959 ECDH P-384 operations in 10031701us (594.0 ops/sec)
Did 10815 ECDSA P-384 signing operations in 10087892us (1072.1 ops/sec)
Did 8976 ECDSA P-384 verify operations in 10071038us (891.3 ops/sec)
Did 2600 ECDH P-521 operations in 10091688us (257.6 ops/sec)
Did 4590 ECDSA P-521 signing operations in 10055195us (456.5 ops/sec)
Did 3811 ECDSA P-521 verify operations in 10003574us (381.0 ops/sec)
After:
Did 77736 ECDH P-256 operations in 10029858us (7750.5 ops/sec) [+0.8%]
Did 7519 ECDH P-384 operations in 10068076us (746.8 ops/sec) [+25.7%]
Did 13335 ECDSA P-384 signing operations in 10029962us (1329.5 ops/sec) [+24.0%]
Did 11021 ECDSA P-384 verify operations in 10088600us (1092.4 ops/sec) [+22.6%]
Did 2912 ECDH P-521 operations in 10001325us (291.2 ops/sec) [+13.0%]
Did 5150 ECDSA P-521 signing operations in 10027462us (513.6 ops/sec) [+12.5%]
Did 4264 ECDSA P-521 verify operations in 10069694us (423.4 ops/sec) [+11.1%]
This more than pays for removing points_make_affine previously and even
speeds up ECDH P-256 slightly. (The point-on-curve check uses the
generic code.)
Next is to push the stack-allocating up to ec_wNAF_mul, followed by a
constant-time single-point multiplication.
Bug: 239
Change-Id: I44a2dff7c52522e491d0f8cffff64c4ab5cd353c
Reviewed-on: https://boringssl-review.googlesource.com/27668
Reviewed-by: Adam Langley <agl@google.com>
This does not appear to actually pull its weight. The purpose of this
logic is to switch some adds to the faster add_mixed in the wNAF code,
at the cost of a rather expensive inversion. This optimization kicks in
for generic curves, so P-384 and P-521:
With:
Did 32130 ECDSA P-384 signing operations in 30077563us (1068.2 ops/sec)
Did 27456 ECDSA P-384 verify operations in 30073086us (913.0 ops/sec)
Did 14122 ECDSA P-521 signing operations in 30077407us (469.5 ops/sec)
Did 11973 ECDSA P-521 verify operations in 30037330us (398.6 ops/sec)
Without:
Did 32445 ECDSA P-384 signing operations in 30069721us (1079.0 ops/sec)
Did 27056 ECDSA P-384 verify operations in 30032303us (900.9 ops/sec)
Did 13905 ECDSA P-521 signing operations in 30000430us (463.5 ops/sec)
Did 11433 ECDSA P-521 verify operations in 30021876us (380.8 ops/sec)
For single-point multiplication, the optimization is not useful. This
makes sense as we only have one table's worth of additions to convert
but still pay for the inversion. For double-point multiplication, it is
slightly useful for P-384 and very useful for P-521. However, the next
change to stack-allocate EC_FELEMs will more than compensate for
removing it. (The immediate goal here is to simplify the EC_FELEM
story.)
Additionally, that this optimization was not useful for single-point
multiplication implies that, should we wish to recover this, a modest
8-entry pre-computed (affine) base point table should have the same
effect or better.
Update-Note: I do not believe anything was calling either of these
functions. (If necessary, we can always add no-op stubs as whether a
point is affine is not visible to external code. It previously kicked in
some optimizations, but those were removed for constant-time needs
anyway.)
Bug: 239
Change-Id: Ic9c51b001c45595cfe592274c7d5d652f4234839
Reviewed-on: https://boringssl-review.googlesource.com/27667
Reviewed-by: Adam Langley <agl@google.com>
We were still using the allocating scalar inversion for ECDSA verify
because previously it seemed to be faster. It appears to have flipped
now, though probably was always just a wash.
While I'm here, save a multiplication by swapping the inversion and
Montgomery reduction.
Did 200000 ECDSA P-256 signing operations in 10025749us (19948.6 ops/sec)
Did 66234 ECDSA P-256 verify operations in 10061123us (6583.2 ops/sec)
Did 202000 ECDSA P-256 signing operations in 10020846us (20158.0 ops/sec)
Did 68052 ECDSA P-256 verify operations in 10020592us (6791.2 ops/sec)
The actual motivation is to get rid of the unchecked EC_SCALAR function
and align sign/verify in preparation for the assembly scalar ops.
Change-Id: I1bd3a5719a67966dc8edaa43535a3864b69f76d0
Reviewed-on: https://boringssl-review.googlesource.com/27588
Reviewed-by: Adam Langley <alangley@gmail.com>
The generic code special-cases affine points, but this leaks
information. (Of course, the generic code also doesn't have a
constant-time multiply and other problems, but one thing at a time.)
The optimization in point doubling is not useful. Point multiplication
more-or-less never doubles an affine point. The optimization in point
addition *is* useful because the wNAF code converts the tables to
affine. Accordingly, align with the P-256 code which adds a 'mixed'
parameter.
(I haven't aligned the formally-verified point formulas themselves yet;
initial testing suggests that the large number of temporaries take a
perf hit with BIGNUM. I'll check the results in EC_FELEM, which will be
stack-allocated, to see if we still need to help the compiler out.)
Strangly, it actually got a bit faster with this change. I'm guessing
because now it doesn't need to bother with unnecessary comparisons and
maybe was kinder to the branch predictor?
Before:
Did 2201 ECDH P-384 operations in 3068341us (717.3 ops/sec)
Did 4092 ECDSA P-384 signing operations in 3076981us (1329.9 ops/sec)
Did 3503 ECDSA P-384 verify operations in 3024753us (1158.1 ops/sec)
Did 992 ECDH P-521 operations in 3017884us (328.7 ops/sec)
Did 1798 ECDSA P-521 signing operations in 3059000us (587.8 ops/sec)
Did 1581 ECDSA P-521 verify operations in 3033142us (521.2 ops/sec)
After:
Did 2310 ECDH P-384 operations in 3092648us (746.9 ops/sec)
Did 4080 ECDSA P-384 signing operations in 3044588us (1340.1 ops/sec)
Did 3520 ECDSA P-384 verify operations in 3056070us (1151.8 ops/sec)
Did 992 ECDH P-521 operations in 3012779us (329.3 ops/sec)
Did 1792 ECDSA P-521 signing operations in 3019459us (593.5 ops/sec)
Did 1600 ECDSA P-521 verify operations in 3047749us (525.0 ops/sec)
Bug: 239
Change-Id: If5d13825fc98e4c58bdd1580cf0245bf7ce93a82
Reviewed-on: https://boringssl-review.googlesource.com/27004
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
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If a caller is in the process on constructing an arbitrary |EC_GROUP|,
and they try to create an |EC_POINT| to set as the generator which is
invalid, we would previously crash.
Change-Id: Ida91354257a02bd56ac29ba3104c9782b8d70f6b
Reviewed-on: https://boringssl-review.googlesource.com/25764
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
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This has no behavior change, but it has a semantic one. This CL is an
assertion that all BIGNUM functions tolerate non-minimal BIGNUMs now.
Specifically:
- Functions that do not touch top/width are assumed to not care.
- Functions that do touch top/width will be changed by this CL. These
should be checked in review that they tolerate non-minimal BIGNUMs.
Subsequent CLs will start adjusting the widths that BIGNUM functions
output, to fix timing leaks.
Bug: 232
Change-Id: I3a2b41b071f2174452f8d3801bce5c78947bb8f7
Reviewed-on: https://boringssl-review.googlesource.com/25257
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 order (and later the field) are used to size stack-allocated fixed
width word arrays. They're also entirely public, so this is fine.
Bug: 232
Change-Id: Ie98869cdbbdfea92dcad64a300f7e0b47bef6bf2
Reviewed-on: https://boringssl-review.googlesource.com/25256
Commit-Queue: David Benjamin <davidben@google.com>
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Reviewed-by: Adam Langley <agl@google.com>
Processing off-curve points is sufficiently dangerous to worry about
code that doesn't check the return value of
|EC_POINT_set_affine_coordinates| and |EC_POINT_oct2point|. While we
have integrated on-curve checks into these functions, code that ignores
the return value will still be able to work with an invalid point
because it's already been installed in the output by the time the check
is done.
Instead, in the event of an off-curve point, set the output point to the
generator, which is certainly on the curve and hopefully safe.
Change-Id: Ibc73dceb2d8d21920e07c4f6def2c8249cb78ca0
Reviewed-on: https://boringssl-review.googlesource.com/25724
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
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These empty states aren't any use to either caller or implementor.
Change-Id: If0b748afeeb79e4a1386182e61c5b5ecf838de62
Reviewed-on: https://boringssl-review.googlesource.com/25254
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>
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>
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>
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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
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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>
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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>
I still need to revive the original CL, but right now I'm interested in
giving every EC_GROUP an order_mont and having different ownership of
that field between built-in and custom groups is kind of a nuisance. If
I'm going to do that anyway, better to avoid computing the entire
EC_GROUP in one go.
I'm using some manual locking rather than CRYPTO_once here so that it
behaves well in the face of malloc errors. Not that we especially care,
but it was easy to do.
This speeds up our ECDH benchmark a bit which otherwise must construct the
EC_GROUP each time (matching real world usage).
Before:
Did 7619 ECDH P-224 operations in 1003190us (7594.8 ops/sec)
Did 7518 ECDH P-256 operations in 1060844us (7086.8 ops/sec)
Did 572 ECDH P-384 operations in 1055878us (541.7 ops/sec)
Did 264 ECDH P-521 operations in 1062375us (248.5 ops/sec)
After:
Did 8415 ECDH P-224 operations in 1066695us (7888.9 ops/sec)
Did 7952 ECDH P-256 operations in 1022819us (7774.6 ops/sec)
Did 572 ECDH P-384 operations in 1055817us (541.8 ops/sec)
Did 264 ECDH P-521 operations in 1060008us (249.1 ops/sec)
Bug: 20
Change-Id: I7446cd0a69a840551dcc2dfabadde8ee1e3ff3e2
Reviewed-on: https://boringssl-review.googlesource.com/23073
Reviewed-by: Adam Langley <agl@google.com>
Later code will take advantage of these invariants. Enforcing them on
custom curves avoids making them go through a custom codepath.
Change-Id: I23cee72a90c2e4846b41e03e6be26bc3abeb4a45
Reviewed-on: https://boringssl-review.googlesource.com/23072
Reviewed-by: Adam Langley <agl@google.com>
Currently we only check that the underlying EC_METHODs match, which
avoids the points being in different forms, but not that the points are
on the same curves. (We fixed the APIs early on so off-curve EC_POINTs
cannot be created.)
In particular, this comes up with folks implementating Java's crypto
APIs with ECDH_compute_key. These APIs are both unfortunate and should
not be mimicked, as they allow folks to mismatch the groups on the two
multiple EC_POINTs. Instead, ECDH APIs should take the public value as a
byte string.
Thanks also to Java's poor crypto APIs, we must support custom curves,
which makes this particularly gnarly. This CL makes EC_GROUP_cmp work
with custom curves and adds an additional subtle requirement to
EC_GROUP_set_generator.
Annoyingly, this change is additionally subtle because we now have a
reference cycle to hack around.
Change-Id: I2efbc4bd5cb65fee5f66527bd6ccad6b9d5120b9
Reviewed-on: https://boringssl-review.googlesource.com/22245
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>
I really need to resurrect the CL to make them entirely static
(https://crbug.com/boringssl/20), but, in the meantime, to make
replacing the EC_METHOD pointer in EC_POINT with EC_GROUP not
*completely* insane, make them refcounted.
OpenSSL did not do this because their EC_GROUPs are mutable
(EC_GROUP_set_asn1_flag and EC_GROUP_set_point_conversion_form). Ours
are immutable but for the two-function dance around custom curves (more
of OpenSSL's habit of making their objects too complex), which is good
enough to refcount.
Change-Id: I3650993737a97da0ddcf0e5fb7a15876e724cadc
Reviewed-on: https://boringssl-review.googlesource.com/22244
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>
This reverts commit f6942f0d22.
Reason for revert: This doesn't actually work in clang-cl. I
forgot we didn't have the clang-cl try bots enabled! :-( I
believe __asm__ is still okay, but I'll try it by hand
tomorrow.
Original change's description:
> Use uint128_t and __asm__ in clang-cl.
>
> clang-cl does not define __GNUC__ but is still a functioning clang. We
> should be able to use our uint128_t and __asm__ code in it on Windows.
>
> Change-Id: I67310ee68baa0c0c947b2441c265b019ef12af7e
> Reviewed-on: https://boringssl-review.googlesource.com/22184
> 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>
TBR=agl@google.com,davidben@google.com
Change-Id: I5c7e0391cd9c2e8cc0dfde37e174edaf5d17db22
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://boringssl-review.googlesource.com/22224
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>
clang-cl does not define __GNUC__ but is still a functioning clang. We
should be able to use our uint128_t and __asm__ code in it on Windows.
Change-Id: I67310ee68baa0c0c947b2441c265b019ef12af7e
Reviewed-on: https://boringssl-review.googlesource.com/22184
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>
crypto/{asn1,x509,x509v3,pem} were skipped as they are still OpenSSL
style.
Change-Id: I3cd9a60e1cb483a981aca325041f3fbce294247c
Reviewed-on: https://boringssl-review.googlesource.com/19504
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>
It's confusing to have both mont and mont_data on EC_GROUP. The
documentation was also wrong.
Change-Id: I4e2e3169ed79307018212fba51d015bbbe5c4227
Reviewed-on: https://boringssl-review.googlesource.com/10348
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 names in the P-224 code collided with the P-256 code and thus many
of the functions and constants in the P-224 code have been prefixed.
Change-Id: I6bcd304640c539d0483d129d5eaf1702894929a8
Reviewed-on: https://boringssl-review.googlesource.com/15847
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>
