Commit Graph

15 Commits

Author SHA1 Message Date
David Benjamin
302bb3964a Small curve25519 cleanups.
Per Brian, x25519_ge_frombytes_vartime does not match the usual
BoringSSL return value convention, and we're slightly inconsistent about
whether to mask the last byte with 63 or 127. (It then gets ANDed with
64, so it doesn't matter which.) Use 127 to align with the curve25519
RFC. Finally, when we invert the transformation, use the same constants
inverted so that they're parallel.

Bug: 243, 244
Change-Id: I0e3aca0433ead210446c58d86b2f57526bde1eac
Reviewed-on: https://boringssl-review.googlesource.com/27984
Reviewed-by: Adam Langley <agl@google.com>
2018-05-02 19:24:00 +00:00
Daniel Hirche
8d4f7e5421 Remove redundant assertion in fe_mul_121666_impl.
Change-Id: Ie2368dc9f6be791b7c3ad1c610dcd603634be6e4
Reviewed-on: https://boringssl-review.googlesource.com/26244
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>
2018-02-27 23:50:02 +00:00
Adam Langley
472ba2c2dd Require that Ed25519 |s| values be < order.
https://tools.ietf.org/html/rfc8032#section-5.1.7 adds this requirement
to prevent signature malleability.

Change-Id: Iac9a3649d97fc69e6efb4aea1ab1e002768fadc9
Reviewed-on: https://boringssl-review.googlesource.com/25564
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>
2018-02-02 20:45:08 +00:00
David Benjamin
884086e0e2 Remove x86_64 x25519 assembly.
Now that we have 64-bit C code, courtesy of fiat-crypto, the tradeoff
for carrying the assembly changes:

Assembly:
Did 16000 Curve25519 base-point multiplication operations in 1059932us (15095.3 ops/sec)
Did 16000 Curve25519 arbitrary point multiplication operations in 1060023us (15094.0 ops/sec)

fiat64:
Did 39000 Curve25519 base-point multiplication operations in 1004712us (38817.1 ops/sec)
Did 14000 Curve25519 arbitrary point multiplication operations in 1006827us (13905.1 ops/sec)

The assembly is still about 9% faster than fiat64, but fiat64 gets to
use the Ed25519 tables for the base point multiplication, so overall it
is actually faster to disable the assembly:

>>> 1/(1/15094.0 + 1/15095.3)
7547.324986004976
>>> 1/(1/38817.1 + 1/13905.1)
10237.73016319501

(At the cost of touching a 30kB table.)

The assembly implementation is no longer pulling its weight. Remove it
and use the fiat code in all build configurations.

Change-Id: Id736873177d5568bb16ea06994b9fcb1af104e33
Reviewed-on: https://boringssl-review.googlesource.com/25524
Reviewed-by: Adam Langley <agl@google.com>
2018-02-01 21:44:58 +00:00
David Benjamin
cb1ad205d0 Use 51-bit limbs from fiat-crypto in 64-bit.
Our 64-bit performance was much lower than it could have been, since we
weren't using the 64-bit multipliers. Fortunately, fiat-crypto is
awesome, so this is just a matter of synthesizing new code and
integration work.

Functions without the signature fiat-crypto curly braces were written by
hand and warrant more review. (It's just redistributing some bits.)

These use the donna variants which takes (and proves) some of the
instruction scheduling from donna as that's significantly faster.
Glancing over things, I suspect but have not confirmed the gap is due to
this:
https://github.com/mit-plv/fiat-crypto/pull/295#issuecomment-356892413

Clang without OPENSSL_SMALL (ECDH omitted since that uses assembly and
is unaffected by this CL).

Before:
Did 105149 Ed25519 key generation operations in 5025208us (20924.3 ops/sec)
Did 125000 Ed25519 signing operations in 5024003us (24880.6 ops/sec)
Did 37642 Ed25519 verify operations in 5072539us (7420.7 ops/sec)

After:
Did 206000 Ed25519 key generation operations in 5020547us (41031.4 ops/sec)
Did 227000 Ed25519 signing operations in 5005232us (45352.5 ops/sec)
Did 69840 Ed25519 verify operations in 5004769us (13954.7 ops/sec)

Clang + OPENSSL_SMALL:

Before:
Did 68598 Ed25519 key generation operations in 5024629us (13652.4 ops/sec)
Did 73000 Ed25519 signing operations in 5067837us (14404.6 ops/sec)
Did 36765 Ed25519 verify operations in 5078684us (7239.1 ops/sec)
Did 74000 Curve25519 base-point multiplication operations in 5016465us (14751.4 ops/sec)
Did 45600 Curve25519 arbitrary point multiplication operations in 5034680us (9057.2 ops/sec)

After:
Did 117315 Ed25519 key generation operations in 5021860us (23360.9 ops/sec)
Did 126000 Ed25519 signing operations in 5003521us (25182.3 ops/sec)
Did 64974 Ed25519 verify operations in 5047790us (12871.8 ops/sec)
Did 134000 Curve25519 base-point multiplication operations in 5058946us (26487.7 ops/sec)
Did 86000 Curve25519 arbitrary point multiplication operations in 5050478us (17028.1 ops/sec)

GCC without OPENSSL_SMALL (ECDH omitted since that uses assembly and
is unaffected by this CL).

Before:
Did 35552 Ed25519 key generation operations in 5030756us (7066.9 ops/sec)
Did 38286 Ed25519 signing operations in 5001648us (7654.7 ops/sec)
Did 10584 Ed25519 verify operations in 5068158us (2088.3 ops/sec)

After:
Did 92158 Ed25519 key generation operations in 5024021us (18343.5 ops/sec)
Did 99000 Ed25519 signing operations in 5011908us (19753.0 ops/sec)
Did 31122 Ed25519 verify operations in 5069878us (6138.6 ops/sec)

Change-Id: Ic0c24d50b4ee2bbc408b94965e9d63319936107d
Reviewed-on: https://boringssl-review.googlesource.com/24805
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>
2018-01-23 22:25:07 +00:00
David Benjamin
a42d7bee85 Reorganize curve25519.c slightly.
Adding 51-bit limbs will require two implementations of most of the
field operations. Group them together to make this more manageable. Also
move the representation-independent functions to the end.

Change-Id: I264e8ac64318a1d5fa72e6ad6f7ccf2f0a2c2be9
Reviewed-on: https://boringssl-review.googlesource.com/24804
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>
2018-01-23 21:42:14 +00:00
David Benjamin
0c1eafc6fe Add additional constants to make_curve25519_tables.py.
These are also constants that depend on the field representation.

Change-Id: I22333c099352ad64eb27fe15ffdc38c6ae7c07ff
Reviewed-on: https://boringssl-review.googlesource.com/24746
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>
2018-01-23 21:35:03 +00:00
David Benjamin
042b49cf3c Extract curve25519 tables into a separate header.
This is in preparation for writing a script to generate them. I'm
manually moving the existing tables over so it will be easier to confirm
the script didn't change the values.

Change-Id: Id83e95c80d981e19d1179d45bf47559b3e1fc86e
Reviewed-on: https://boringssl-review.googlesource.com/24744
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>
2018-01-23 21:08:49 +00:00
David Benjamin
186df3a655 Implement fe_sq2_tt with fe_sq_tt.
fiat-crypto only generates fe_mul and fe_sq, but the original Ed25519
implementation we had also had fe_sq2 for computing 2*f^2. Previously,
we inlined a version of fe_mul.

Instead, we could implement it with fe_sq and fe_add. Performance-wise,
this seems to not regress. If anything, it makes it faster?

Before (clang, run for 10 seconds):
Did 243000 Ed25519 key generation operations in 10025910us (24237.2 ops/sec)
Did 250000 Ed25519 signing operations in 10035580us (24911.4 ops/sec)
Did 73305 Ed25519 verify operations in 10071101us (7278.7 ops/sec)
Did 184000 Curve25519 base-point multiplication operations in 10040138us (18326.4 ops/sec)
Did 186000 Curve25519 arbitrary point multiplication operations in 10052721us (18502.5 ops/sec)

After (clang, run for 10 seconds):
Did 242424 Ed25519 key generation operations in 10013117us (24210.6 ops/sec)
Did 253000 Ed25519 signing operations in 10011744us (25270.3 ops/sec)
Did 73899 Ed25519 verify operations in 10048040us (7354.6 ops/sec)
Did 194000 Curve25519 base-point multiplication operations in 10005389us (19389.6 ops/sec)
Did 195000 Curve25519 arbitrary point multiplication operations in 10028443us (19444.7 ops/sec)

Before (clang + OPENSSL_SMALL, run for 10 seconds):
Did 144000 Ed25519 key generation operations in 10019344us (14372.2 ops/sec)
Did 146000 Ed25519 signing operations in 10011653us (14583.0 ops/sec)
Did 74052 Ed25519 verify operations in 10005789us (7400.9 ops/sec)
Did 150000 Curve25519 base-point multiplication operations in 10007468us (14988.8 ops/sec)
Did 91392 Curve25519 arbitrary point multiplication operations in 10057678us (9086.8 ops/sec)

After (clang + OPENSSL_SMALL, run for 10 seconds):
Did 144000 Ed25519 key generation operations in 10066724us (14304.6 ops/sec)
Did 148000 Ed25519 signing operations in 10062043us (14708.7 ops/sec)
Did 74820 Ed25519 verify operations in 10058557us (7438.4 ops/sec)
Did 151000 Curve25519 base-point multiplication operations in 10063492us (15004.7 ops/sec)
Did 90402 Curve25519 arbitrary point multiplication operations in 10049141us (8996.0 ops/sec)

Change-Id: I31e9f61833492c3ff2dfd78e1dee5e06f43c850f
Reviewed-on: https://boringssl-review.googlesource.com/24724
Reviewed-by: Adam Langley <agl@google.com>
2018-01-23 20:49:50 +00:00
David Benjamin
00208b443c Use fiat-crypto's freeze function for fe_tobytes.
It requires a handful of additional intrinsics for now.

Fiat's freeze function only works on the tight bounds, so fe_isnonzero
gains an extra fe_carry. But all other calls of fe_tobytes are of tight
bounds anyway.

Change-Id: I834858cee7863c7344e456d7a7dbf4f414f04ae5
Reviewed-on: https://boringssl-review.googlesource.com/24545
Reviewed-by: Adam Langley <agl@google.com>
2018-01-05 23:38:26 +00:00
David Benjamin
915c121bb5 Remove some outdated preconditions and postconditions.
These date to the old code and have been replaced by the fe and fe_loose
bounds in the header file. Also fix up a comment that the comment
converter didn't manage to convert.

Change-Id: I2e3ea867a8cea2b347d09c304a17e532b2e36545
Reviewed-on: https://boringssl-review.googlesource.com/24525
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>
2018-01-03 23:03:32 +00:00
David Benjamin
3144d92ab8 Add some missing array parameter length annotations.
Not that anything checks them...

Change-Id: Iae1b5dbdb3c20a9ebd841bcd32cc5c725c68eb01
Reviewed-on: https://boringssl-review.googlesource.com/24524
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>
2018-01-03 22:34:22 +00:00
Andres Erbsen
0a54e99848 Add links to proofs of elliptic curve formulas.
Change-Id: I166f740185f26770b51759714efd5d634fbcc173
Reviewed-on: https://boringssl-review.googlesource.com/24424
Reviewed-by: David Benjamin <davidben@google.com>
2017-12-22 19:52:44 +00:00
Adam Langley
b2c312d670 curve25519: fiat-crypto field arithmetic.
Each operation was translated from fiat-crypto output using fiat-crypto
prettyprint.py. For example fe_mul is synthesized in
https://github.com/mit-plv/fiat-crypto/blob/master/src/Specific/X25519/C32/femul.v,
and shown in the last Coq-compatible form at
https://github.com/mit-plv/fiat-crypto/blob/master/src/Specific/X25519/C32/femulDisplay.log.

Benchmarks on Google Cloud's unidentified Intel Xeon with AVX2:

git checkout $VARIANT && ( cd build && rm -rf * && CC=clang CXX=clang++ cmake -GNinja -DCMAKE_TOOLCHAIN_FILE=../util/32-bit-toolchain.cmake -DCMAKE_BUILD_TYPE=Release .. && ninja && ./tool/bssl speed -filter 25519 )

this branch:

Did 11382 Ed25519 key generation operations in 1053046us (10808.6 ops/sec)
Did 11169 Ed25519 signing operations in 1038080us (10759.3 ops/sec)
Did 2925 Ed25519 verify operations in 1001346us (2921.1 ops/sec)
Did 12000 Curve25519 base-point multiplication operations in 1084851us (11061.4 ops/sec)
Did 3850 Curve25519 arbitrary point multiplication operations in 1085565us (3546.5 ops/sec)

Did 11466 Ed25519 key generation operations in 1049821us (10921.9 ops/sec)
Did 11000 Ed25519 signing operations in 1013317us (10855.4 ops/sec)
Did 3047 Ed25519 verify operations in 1043846us (2919.0 ops/sec)
Did 12000 Curve25519 base-point multiplication operations in 1068924us (11226.2 ops/sec)
Did 3850 Curve25519 arbitrary point multiplication operations in 1090598us (3530.2 ops/sec)

Did 10309 Ed25519 key generation operations in 1003320us (10274.9 ops/sec)
Did 11000 Ed25519 signing operations in 1017862us (10807.0 ops/sec)
Did 3135 Ed25519 verify operations in 1098624us (2853.6 ops/sec)
Did 9000 Curve25519 base-point multiplication operations in 1046608us (8599.2 ops/sec)
Did 3132 Curve25519 arbitrary point multiplication operations in 1038963us (3014.5 ops/sec)

master:

Did 11564 Ed25519 key generation operations in 1068762us (10820.0 ops/sec)
Did 11104 Ed25519 signing operations in 1024278us (10840.8 ops/sec)
Did 3206 Ed25519 verify operations in 1049179us (3055.7 ops/sec)
Did 12000 Curve25519 base-point multiplication operations in 1073619us (11177.1 ops/sec)
Did 3550 Curve25519 arbitrary point multiplication operations in 1000279us (3549.0 ops/sec)
andreser@linux-andreser:~/boringssl$ build/tool/bssl speed -filter 25519
Did 11760 Ed25519 key generation operations in 1072495us (10965.1 ops/sec)
Did 10800 Ed25519 signing operations in 1003486us (10762.5 ops/sec)
Did 3245 Ed25519 verify operations in 1080399us (3003.5 ops/sec)
Did 12000 Curve25519 base-point multiplication operations in 1076021us (11152.2 ops/sec)
Did 3570 Curve25519 arbitrary point multiplication operations in 1005087us (3551.9 ops/sec)
andreser@linux-andreser:~/boringssl$ build/tool/bssl speed -filter 25519
Did 11438 Ed25519 key generation operations in 1041115us (10986.3 ops/sec)
Did 11000 Ed25519 signing operations in 1012589us (10863.2 ops/sec)
Did 3312 Ed25519 verify operations in 1082834us (3058.6 ops/sec)
Did 12000 Curve25519 base-point multiplication operations in 1061318us (11306.7 ops/sec)
Did 3580 Curve25519 arbitrary point multiplication operations in 1004923us (3562.5 ops/sec)

squashed: curve25519: convert field constants to unsigned.

import re, sys, math

def weight(i):
    return 2**int(math.ceil(25.5*i))

def convert(t):
    limbs = [x for x in t.groups() if x.replace('-','').isdigit()]
    v = sum(weight(i)*x for (i,x) in enumerate(map(int, limbs))) % (2**255-19)
    limbs = [(v % weight(i+1)) // weight(i) for i in range(10)]
    assert v == sum(weight(i)*x for (i,x) in enumerate(limbs))

    i = 0
    ret = ''
    for s in t.groups():
        if s.replace('-','').isdigit():
            ret += str(limbs[i])
            i += 1
        else:
            ret += s
    return ret

fe_re = re.compile(r'(\s*,\s*)'.join(r'(-?\d+)' for i in range(10)))
print (re.sub(fe_re, convert, sys.stdin.read()))

Change-Id: Ibd4f7f5c38e5c4d61c9826afb406baebe2be5168
Reviewed-on: https://boringssl-review.googlesource.com/22385
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>
2017-11-03 22:39:31 +00:00
Andres Erbsen
5b280a80df Move curve25519 code to third_party/fiat.
This change doesn't actually introduce any Fiat code yet. It sets up the
directory structure to make the diffs in the next change clearer.

Change-Id: I38a21fb36b18a08b0907f9d37b7ef5d7d3137ede
Reviewed-on: https://boringssl-review.googlesource.com/22624
Reviewed-by: David Benjamin <davidben@google.com>
2017-11-03 22:23:59 +00:00