Commit Graph

362 Commits

Author SHA1 Message Date
Brian Smith
fee8709f69 Replace |alloca| in |BN_mod_exp_mont_consttime|.
|alloca| is dangerous and poorly specified, according to any
description of |alloca|. It's also hard for some analysis tools to
reason about.

The code here assumed |alloca| is a macro, which isn't a valid
assumption. Depending on what which headers are included and what
toolchain is being used, |alloca| may or may not be defined as a macro,
and this might change over time if/when toolchains are updated. Or, we
might be doing static analysis and/or dynamic analysis with a different
configuration w.r.t. the availability of |alloca| than production
builds use.

Regardless, the |alloca| code path only kicked in when the inputs are
840 bits or smaller. Since the multi-prime RSA support was removed, for
interesting RSA key sizes the input will be at least 1024 bits and this
code path won't be triggered since powerbufLen will be larger than 3072
bytes in those cases. ECC inversion via Fermat's Little Theorem has its
own constant-time exponentiation so there are no cases where smaller
inputs need to be fast.

The RSAZ code avoids the |OPENSSL_malloc| for 2048-bit RSA keys.
Increasingly the RSAZ code won't be used though, since it will be
skipped over on Broadwell+ CPUs. Generalize the RSAZ stack allocation
to work for non-RSAZ code paths. In order to ensure this doesn't cause
too much stack usage on platforms where RSAZ wasn't already being used,
only do so on x86-64, which already has this large stack size
requirement due to RSAZ.

This change will make it easier to refactor |BN_mod_exp_mont_consttime|
to do that more safely and in a way that's more compatible with various
analysis tools.

This is also a step towards eliminating the |uintptr_t|-based alignment
hack.

Since this change increases the number of times |OPENSSL_free| is
skipped, I've added an explicit |OPENSSL_cleanse| to ensure the
zeroization is done. This should be done regardless of the other changes
here.

Change-Id: I8a161ce2720a26127e85fff7513f394883e50b2e
Reviewed-on: https://boringssl-review.googlesource.com/28584
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: David Benjamin <davidben@google.com>
2018-05-21 19:43:05 +00:00
Adam Langley
63e2a08123 Spell Falko Strenzke's name correctly.
Thanks to Brian Smith for pointing this out.

Change-Id: I27ae58df0028bc6aa3a11741acb5453369e202cc
Reviewed-on: https://boringssl-review.googlesource.com/28625
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>
2018-05-21 18:18:04 +00:00
David Benjamin
2f5100e629 More compatibility stuff.
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>
2018-05-15 23:57:53 +00:00
Adam Langley
91254c244c Rename |asm_AES_*| to |aes_nohw_*|.
Rather than have plain-C functions, asm functions, and accelerated
functions, just have accelerated and non-accelerated, where the latter
are either provided by assembly or by C code.

Pertinently, this allows Aarch64 to use hardware accel for the basic
|AES_*| functions.

Change-Id: I0003c0c7a43d85a3eee8c8f37697f61a3070dd40
Reviewed-on: https://boringssl-review.googlesource.com/28385
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>
2018-05-15 23:02:52 +00:00
David Benjamin
d12f2ba55e Tweak RSA errors for compatibility.
cryptography.io wants RSA_R_BLOCK_TYPE_IS_NOT_02, only used by the
ancient RSA_padding_check_SSLv23 function. Define it but never emit it.

Additionally, it's rather finicky about RSA_R_TOO_LARGE* errors. We
merged them in BoringSSL because having RSA_R_TOO_LARGE,
RSA_R_TOO_LARGE_FOR_MODULUS, and RSA_R_TOO_LARGE_FOR_KEY_SIZE is a
little silly. But since we don't expect well-behaved code to condition
on error codes anyway, perhaps that wasn't worth it.  Split them back
up.

Looking through OpenSSL, there is a vague semantic difference:

RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY - Specifically emitted if a digest is
too big for PKCS#1 signing with this key.

RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE - You asked me to sign or encrypt a
digest/plaintext, but it's too big for this key.

RSA_R_DATA_TOO_LARGE_FOR_MODULUS - You gave me an RSA ciphertext or
signature and it is not fully reduced modulo N.
-OR-
The padding functions produced something that isn't reduced, but I
believe this is unreachable outside of RSA_NO_PADDING.

RSA_R_DATA_TOO_LARGE - Some low-level padding function was told to copy
a digest/plaintext into some buffer, but the buffer was too small. I
think this is basically unreachable.
-OR-
You asked me to verify a PSS signature, but I didn't need to bother
because the digest/salt parameters you picked were too big.

Update-Note: This depends on cl/196566462.
Change-Id: I2e539e075eff8bfcd52ccde365e975ebcee72567
Reviewed-on: https://boringssl-review.googlesource.com/28547
Reviewed-by: Adam Langley <agl@google.com>
2018-05-15 23:02:49 +00:00
Adam Langley
05750f23ae Revert "Revert "Revert "Revert "Make x86(-64) use the same aes_hw_* infrastructure as POWER and the ARMs.""""
This was reverted a second time because it ended up always setting the
final argument to CRYPTO_gcm128_init to zero, which disabled some
acceleration of GCM on ≥Haswell. With this update, that argument will be
set to 1 if |aes_hw_*| functions are being used.

Probably this will need to be reverted too for some reason. I'm hoping
to fill the entire git short description with “Revert”.

Change-Id: Ib4a06f937d35d95affdc0b63f29f01c4a8c47d03
Reviewed-on: https://boringssl-review.googlesource.com/28484
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>
2018-05-14 22:09:29 +00:00
Adam Langley
69271b5d4f Revert "Revert "Revert "Make x86(-64) use the same aes_hw_* infrastructure as POWER and the ARMs."""
gcm.c's AES-NI code wasn't triggering. (Thanks Brain for noting.)

Change-Id: Ic740e498b94fece180ac35c449066aee1349cbd5
Reviewed-on: https://boringssl-review.googlesource.com/28424
Reviewed-by: Adam Langley <alangley@gmail.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2018-05-12 15:18:16 +00:00
Adam Langley
7d1f35985b Show an error before we abort the process for an entropy failure.
Change-Id: I8d8483d38de15dcde18141bb9cc9e79d585d24ad
Reviewed-on: https://boringssl-review.googlesource.com/27045
Reviewed-by: Adam Langley <agl@google.com>
2018-05-11 22:30:24 +00:00
David Benjamin
99767ecdd4 Enable ADX assembly.
Build (and carry) issues are now resolved (as far as we know). Let's try
this again...

Measurements on a Skylake VM (so a little noisy).

Before:
Did 3135 RSA 2048 signing operations in 3015866us (1039.5 ops/sec)
Did 89000 RSA 2048 verify (same key) operations in 3007271us (29594.9 ops/sec)
Did 66000 RSA 2048 verify (fresh key) operations in 3014363us (21895.2 ops/sec)
Did 324 RSA 4096 signing operations in 3004364us (107.8 ops/sec)
Did 23126 RSA 4096 verify (same key) operations in 3003398us (7699.9 ops/sec)
Did 21312 RSA 4096 verify (fresh key) operations in 3017043us (7063.9 ops/sec)
Did 31040 ECDH P-256 operations in 3024273us (10263.6 ops/sec)
Did 91000 ECDSA P-256 signing operations in 3019740us (30135.0 ops/sec)
Did 25678 ECDSA P-256 verify operations in 3046975us (8427.4 ops/sec)

After:
Did 3640 RSA 2048 signing operations in 3035845us (1199.0 ops/sec)
Did 129000 RSA 2048 verify (same key) operations in 3003691us (42947.2 ops/sec)
Did 105000 RSA 2048 verify (fresh key) operations in 3029935us (34654.2 ops/sec)
Did 510 RSA 4096 signing operations in 3014096us (169.2 ops/sec)
Did 38000 RSA 4096 verify (same key) operations in 3092814us (12286.5 ops/sec)
Did 34221 RSA 4096 verify (fresh key) operations in 3003817us (11392.5 ops/sec)
Did 38000 ECDH P-256 operations in 3061758us (12411.2 ops/sec)
Did 116000 ECDSA P-256 signing operations in 3001637us (38645.6 ops/sec)
Did 35100 ECDSA P-256 verify operations in 3023872us (11607.6 ops/sec)

Tested with Intel SDE.

Change-Id: Ib27c0d6012d14274e331ab03f958e5a0c8b7e885
Reviewed-on: https://boringssl-review.googlesource.com/28104
Reviewed-by: Adam Langley <agl@google.com>
2018-05-11 21:57:13 +00:00
Adam Langley
29d97ff333 Revert "Revert "Make x86(-64) use the same aes_hw_* infrastructure as POWER and the ARMs.""
This relands
https://boringssl-review.googlesource.com/c/boringssl/+/28026 with a
change to avoid calling the Aarch64 hardware functions when the set has
been set by C code, since these are seemingly incompatible.

Change-Id: I91f3ed41cf6f7a7ce7a0477753569fac084c528b
Reviewed-on: https://boringssl-review.googlesource.com/28384
Reviewed-by: Adam Langley <agl@google.com>
2018-05-11 19:16:49 +00:00
Adam Langley
aca24c8724 Revert "Make x86(-64) use the same aes_hw_* infrastructure as POWER and the ARMs."
Broke Aarch64 on the main builders (but not the trybots, somehow.)

Change-Id: I53eb09c99ef42a59628b0506b5ddb125299b554a
Reviewed-on: https://boringssl-review.googlesource.com/28364
Reviewed-by: Adam Langley <agl@google.com>
2018-05-11 17:39:50 +00:00
Adam Langley
26ba48a6fb Make x86(-64) use the same aes_hw_* infrastructure as POWER and the ARMs.
This also happens to make the AES_[en|de]crypt functions use AES-NI
(where available) on Intel.

Update-Note: this substantially changes how AES-NI is triggered. Worth running bssl speed (on both k8 and ppc), before and after, to confirm that there are no regressions.

Change-Id: I5f22c1975236bbc1633c24ab60d683bca8ddd4c3
Reviewed-on: https://boringssl-review.googlesource.com/28026
Reviewed-by: David Benjamin <davidben@google.com>
2018-05-11 00:16:39 +00:00
Adam Langley
f64c373784 Fix build with GCC 4.9.2 and -Wtype-limits.
gRPC builds on Debian Jessie, which has GCC 4.9.2, and builds with
-Wtype-limits, which makes it warn about code intended for 64-bit
systems when building on 32-bit systems.

We have tried to avoid these issues with Clang previously by guarding
with “sizeof(size_t) > 4”, but this version of GCC isn't smart enough to
figure that out.

Change-Id: I800ceb3891436fa7c81474ede4b8656021568357
Reviewed-on: https://boringssl-review.googlesource.com/28247
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>
2018-05-08 22:21:45 +00:00
David Benjamin
bb3a456930 Move some RSA keygen support code into separate files.
This was all new code. There was a request to make this available under
ISC.

Change-Id: Ibabbe6fbf593c2a781aac47a4de7ac378604dbcf
Reviewed-on: https://boringssl-review.googlesource.com/28267
Reviewed-by: Adam Langley <agl@google.com>
2018-05-08 21:25:46 +00:00
David Benjamin
5d626b223b Add some more compatibility functions.
Change-Id: I56afcd896cb9de1c69c788b4f6395f4e78140d81
Reviewed-on: https://boringssl-review.googlesource.com/28265
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>
2018-05-08 20:51:15 +00:00
Adam Langley
57eaeaba24 Fix include path.
This happened to be working only because of lucky -I argument and At the
same time, include digest.h since this file references |EVP_sha1| and
other digest-related functions.

Change-Id: I0095ea8f5ef21f6e63b3dc819932b38178e09693
Reviewed-on: https://boringssl-review.googlesource.com/28244
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>
2018-05-08 16:26:05 +00:00
David Benjamin
0318b051ee Add some OpenSSL compatibility functions and hacks.
Change-Id: Ie42e57441f5fd7d1557a7fc1c648cf3f28b9c4db
Reviewed-on: https://boringssl-review.googlesource.com/28224
Commit-Queue: David Benjamin <davidben@google.com>
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>
2018-05-08 01:22:04 +00:00
David Benjamin
2a92847c24 Restore some MSVC warnings.
bcm.c means e_aes.c can no longer be lazy about warning push/pop.

Change-Id: I558041bab3baa00e3adc628fe19486545d0f6be3
Reviewed-on: https://boringssl-review.googlesource.com/28164
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>
2018-05-07 19:03:30 +00:00
David Benjamin
bf33114b51 Rename third_party/wycheproof to satisfy a bureaucrat.
Make it clear this is not a pristine full copy of all of Wycheproof as a
library.

Change-Id: I1aa5253a1d7c696e69b2e8d7897924f15303d9ac
Reviewed-on: https://boringssl-review.googlesource.com/28188
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Martin Kreichgauer <martinkr@google.com>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2018-05-07 18:33:50 +00:00
David Benjamin
179c4e257a Update Wycheproof, add keywrap tests, and fix a bug.
The bug, courtesy of Wycheproof, is that AES key wrap requires the input
be at least two blocks, not one. This also matches the OpenSSL behavior
of those two APIs.

Update-Note: AES_wrap_key with in_len = 8 and AES_unwrap_key with
in_len = 16 will no longer work.

Change-Id: I5fc63ebc16920c2f9fd488afe8c544e0647d7507
Reviewed-on: https://boringssl-review.googlesource.com/27925
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>
2018-05-04 17:08:44 +00:00
Matthew Braithwaite
cf341d028f Add missing #include of <openssl/mem.h>.
Change-Id: I0674f4e9b15b546237600fb2486c46aac7cb0716
Reviewed-on: https://boringssl-review.googlesource.com/28027
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>
2018-05-04 16:51:04 +00:00
David Benjamin
f6d9f0b58e bn/asm/*-mont.pl: fix memory access pattern in final subtraction.
Montgomery multiplication post-conditions in some of code paths were
formally non-constant time. Cache access pattern was result-neutral,
but a little bit asymmetric, which might have produced a signal [if
processor reordered load and stores at run-time].

(Imported from upstream's 774ff8fed67e19d4f5f0df2f59050f2737abab2a.)

Change-Id: I77443fb79242b77e704c34d69f1de9e3162e9538
Reviewed-on: https://boringssl-review.googlesource.com/27987
Reviewed-by: Adam Langley <agl@google.com>
2018-05-03 23:21:22 +00:00
Adam Langley
0c9ac2e7bf Drop FULL_UNROLL code in aes.c.
We've never defined this so this code has always been dead.

Change-Id: Ibcc4095bf812c7e1866c5f39968789606f0995ae
Reviewed-on: https://boringssl-review.googlesource.com/28024
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>
2018-05-03 16:10:14 +00:00
David Benjamin
8e75ae4880 Add a Wycheproof driver for AES-CBC.
Change-Id: I782ea51e1db8d05f552832a7c6910954fa2dda5f
Reviewed-on: https://boringssl-review.googlesource.com/27924
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>
2018-05-02 19:41:48 +00:00
Matthew Braithwaite
58d6fc48cc Add missing #include of <openssl/err.h>.
Change-Id: Ib2ce220e31a4f808999934197a7f43b8723131e8
Reviewed-on: https://boringssl-review.googlesource.com/27884
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>
2018-05-01 01:00:44 +00:00
David Benjamin
8370fb6b41 Implement constant-time generic multiplication.
This is slower, but constant-time. It intentionally omits the signed
digit optimization because we cannot be sure the doubling case will be
unreachable for all curves. This is a fallback generic implementation
for curves which we must support for compatibility but which are not
common or important enough to justify curve-specific work.

Before:
Did 814 ECDH P-384 operations in 1085384us (750.0 ops/sec)
Did 1430 ECDSA P-384 signing operations in 1081988us (1321.6 ops/sec)
Did 308 ECDH P-521 operations in 1057741us (291.2 ops/sec)
Did 539 ECDSA P-521 signing operations in 1049797us (513.4 ops/sec)

After:
Did 715 ECDH P-384 operations in 1080161us (661.9 ops/sec)
Did 1188 ECDSA P-384 verify operations in 1069567us (1110.7 ops/sec)
Did 275 ECDH P-521 operations in 1060503us (259.3 ops/sec)
Did 506 ECDSA P-521 signing operations in 1084739us (466.5 ops/sec)

But we're still faster than the old BIGNUM implementation. EC_FELEM
more than paid for both the loss of points_make_affine and this CL.

Bug: 239
Change-Id: I65d71a731aad16b523928ee47618822d503ea704
Reviewed-on: https://boringssl-review.googlesource.com/27708
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>
2018-04-27 20:11:29 +00:00
David Benjamin
8b0dc7a720 Simplify ec_wNAF_mul table sizing.
w=4 appears to be the correct answer for P-224 through P-521. There's
nominally some optimizations in here for 70- and 20-bit primes, but
that's absurd.

Change-Id: Id4ccec779b17e375e9258c1784e46d7d3651c59a
Reviewed-on: https://boringssl-review.googlesource.com/27707
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>
2018-04-27 19:49:08 +00:00
David Benjamin
041dd68cec Clear mallocs in ec_wNAF_mul.
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>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2018-04-27 19:44:58 +00:00
David Benjamin
e14e4a7ee3 Remove ec_compute_wNAF's failure cases.
Replace them with asserts and better justify why each of the internal
cases are not reachable. Also change the loop to count up to bits+1 so
it is obvious there is no memory error. (The previous loop shape made
more sense when ec_compute_wNAF would return a variable length
schedule.)

Change-Id: I9c7df6abac4290b7a3e545e3d4aa1462108e239e
Reviewed-on: https://boringssl-review.googlesource.com/27705
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>
2018-04-27 19:24:58 +00:00
Adam Langley
cece32610b Add SHA256_TransformBlocks.
Rather than expose a (potentially) assembly function directly, wrap it
in a C function to make visibility control easier.

Change-Id: I4a2dfeb8999ff021b2e10fbc54850eeadabbefff
Reviewed-on: https://boringssl-review.googlesource.com/27724
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>
2018-04-25 17:51:50 +00:00
David Benjamin
ec4f0ddafc EC_GROUP_dup cannot fail.
We've since ref-counted it.

Change-Id: I5589e79f5bbba35b02ae659c7aa6ac76ba0082a3
Reviewed-on: https://boringssl-review.googlesource.com/27669
Reviewed-by: Adam Langley <agl@google.com>
2018-04-25 16:43:19 +00:00
David Benjamin
32e0d10069 Add EC_FELEM for EC_POINTs and related temporaries.
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>
2018-04-25 16:39:58 +00:00
David Benjamin
6a289b3ec4 Remove EC_POINTs_make_affine and related logic.
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>
2018-04-25 16:12:06 +00:00
David Benjamin
06d467c58a ghashv8-armx.pl: add Qualcomm Kryo results.
(Imported from upstream's 753316232243ccbf86b96c1c51ffcb41651d9ad5.)

Just to sync up a bit further.

Change-Id: I805150d0f0c10d68648fae83603b0d46231ae4ec
Reviewed-on: https://boringssl-review.googlesource.com/27685
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>
2018-04-24 19:48:59 +00:00
David Benjamin
a7c8f2b7b0 ghashv8-armvx.pl: Fix various typos.
(Imported from upstream's 46f4e1bec51dc96fa275c168752aa34359d9ee51.)

Change-Id: Ie9c1e9cfc38a3962e3674a68bc0174d064272fc2
Reviewed-on: https://boringssl-review.googlesource.com/27684
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>
2018-04-24 19:48:49 +00:00
David Benjamin
a63d0ad40d Require BN_mod_exp_mont* inputs be reduced.
If the caller asked for the base to be treated as secret, we should
provide that. Allowing unbounded inputs is not compatible with being
constant-time.

Additionally, this aligns with the guidance here:
https://github.com/HACS-workshop/spectre-mitigations/blob/master/crypto_guidelines.md#1-do-not-conditionally-choose-between-constant-and-non-constant-time

Update-Note: BN_mod_exp_mont_consttime and BN_mod_exp_mont now require
inputs be fully reduced. I believe current callers tolerate this.

Additionally, due to a quirk of how certain operations were ordered,
using (publicly) zero exponent tolerated a NULL BN_CTX while other
exponents required non-NULL BN_CTX. Non-NULL BN_CTX is now required
uniformly. This is unlikely to cause problems. Any call site where the
exponent is always zero should just be replaced with BN_value_one().

Change-Id: I7c941953ea05f36dc2754facb9f4cf83a6789c61
Reviewed-on: https://boringssl-review.googlesource.com/27665
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Steven Valdez <svaldez@google.com>
2018-04-24 18:29:29 +00:00
David Benjamin
5c0e0cec83 Remove Z = 1 special-case in generic point_get_affine.
As the point may be the output of some private key operation, whether Z
accidentally hit one is secret.

Bug: 239
Change-Id: I7db34cd3b5dd5ca4b96980e8993a9b4eda49eb88
Reviewed-on: https://boringssl-review.googlesource.com/27664
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:16:53 +00:00
David Benjamin
f5858ca008 Remove unnecessary endian flip in p224-64.c.
We have little-endian BIGNUM functions now.

Change-Id: Iffc46a14e75c6bba2e170b824b1a08c69d2e9d18
Reviewed-on: https://boringssl-review.googlesource.com/27594
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:15:28 +00:00
David Benjamin
b8f14b7d53 Add dedicated scalar inversion code to p256-x86_64.c.
This is adapted from upstream's
eb7916960bf50f436593abe3d5f2e0592d291017.

This gives a 22% win for ECDSA signing. (Upstream cites 30-40%, but they
are unnecessarily using BN_mod_exp_mont_consttime in their generic path.
The exponent is public. I expect part of their 30-40% is just offsetting
this.)

Did 506000 ECDSA P-256 signing operations in 25044595us (20204.0 ops/sec)
Did 170506 ECDSA P-256 verify operations in 25033567us (6811.1 ops/sec)

Did 618000 ECDSA P-256 signing operations in 25031294us (24689.1 ops/sec)
Did 182240 ECDSA P-256 verify operations in 25006918us (7287.6 ops/sec)

Most of the performance win appears to be from the assembly operations
and not the addition chain. I have a CL to graft the addition chain onto
the C implementation, but it did not show measurable improvement in
ECDSA verify. ECDSA sign gets 2-4% faster, but we're more concerned
about ECDSA verify in the OPENSSL_SMALL builds.

Change-Id: Ide166f98b146c025f7f80ed7906336c16818540a
Reviewed-on: https://boringssl-review.googlesource.com/27593
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:14:57 +00:00
David Benjamin
364a51ec3a Abstract scalar inversion in EC_METHOD.
This introduces a hook for the OpenSSL assembly.

Change-Id: I35e0588f0ed5bed375b12f738d16c9f46ceedeea
Reviewed-on: https://boringssl-review.googlesource.com/27592
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:13:24 +00:00
David Benjamin
b27b579fdd Add some tests for scalar operations.
Largely random data, but make it easy to add things in the future.

Change-Id: I30bee790bd9671b4d0327c2244fe5cd1a8954f90
Reviewed-on: https://boringssl-review.googlesource.com/27591
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:12:34 +00:00
David Benjamin
3861ae662a p256-x86_64-asm.pl: add .cfi and SEH handlers to new functions.
Imported from upstream's d5e11843fe430dfa89bdf83b6f7805c709dcdb41.

Change-Id: Ie6d64ef821b66531995b43d015ab2755558eaa57
Reviewed-on: https://boringssl-review.googlesource.com/27590
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:10:08 +00:00
David Benjamin
5c30dab835 Import P-256 scalar multiplication assembly from OpenSSL.
This imports the assembly portion of
eb7916960bf50f436593abe3d5f2e0592d291017 from upstream. Note the
OPENSSL_ia32cap_P bits were tweaked to be delocate-compatible. Those
should be reviewed against the original file.

Change-Id: I19eef722225bb7928275e3d93890f80aa2f8734d
Reviewed-on: https://boringssl-review.googlesource.com/27589
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 16:09:08 +00:00
David Benjamin
7121fe24e9 Align ECDSA sign/verify scalar inversions.
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>
2018-04-24 16:00:12 +00:00
David Benjamin
941f535438 Abstract away EC_SCALAR operations.
Just a little bit cleaner.

Change-Id: I0ed192a531b5aa853ba082caa6088e838f12c863
Reviewed-on: https://boringssl-review.googlesource.com/27587
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 15:37:40 +00:00
David Benjamin
9291be5b27 Remove return values from bn_*_small.
No sense in adding impossible error cases we need to handle.
Additionally, tighten them a bit and require strong bounds. (I wasn't
sure what we'd need at first and made them unnecessarily general.)

Change-Id: I21a0afde90a55be2e9a0b8d7288f595252844f5f
Reviewed-on: https://boringssl-review.googlesource.com/27586
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 15:34:32 +00:00
David Benjamin
3f8074c2de Fix the error on overly large group orders.
Change-Id: I9b11fabb79b5dfe031ac5ea2f021b28b87262761
Reviewed-on: https://boringssl-review.googlesource.com/27585
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 15:27:17 +00:00
David Benjamin
cd01254900 Explicitly guarantee BN_MONT_CTX::{RR,N} have the same width.
This is so the *_small functions can assume somewhat more uniform
widths, to simplify their error-handling.

Change-Id: I0420cb237084b253e918c64b0c170a5dfd99ab40
Reviewed-on: https://boringssl-review.googlesource.com/27584
Reviewed-by: Adam Langley <alangley@gmail.com>
2018-04-24 15:22:09 +00:00
David Benjamin
a2938719a4 Improve the RSA key generation failure probability.
The FIPS 186-4 algorithm we use includes a limit which hits a 2^-20
failure probability, assuming my math is right. We've observed roughly
2^-23. This is a little large at scale. (See b/77854769.)

To avoid modifying the FIPS algorithm, retry the whole thing four times
to bring the failure rate down to 2^-80. Along the way, now that I have
the derivation on hand, adjust
https://boringssl-review.googlesource.com/22584 to target the same
failure probability.

Along the way, fix an issue with RSA_generate_key where, if callers
don't check for failure, there may be half a key in there.

Change-Id: I0e1da98413ebd4ffa65fb74c67a58a0e0cd570ff
Reviewed-on: https://boringssl-review.googlesource.com/27288
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>
2018-04-20 21:34:05 +00:00
David Benjamin
9af9b946d2 Restore the BN_mod codepath for public Montgomery moduli.
https://boringssl-review.googlesource.com/10520 and then later
https://boringssl-review.googlesource.com/25285 made BN_MONT_CTX_set
constant-time, which is necessary for RSA's mont_p and mont_q. However,
due to a typo in the benchmark, they did not correctly measure.

Split BN_MONT_CTX creation into a constant-time and variable-time one.
The constant-time one uses our current algorithm and the latter restores
the original BN_mod codepath.

Should we wish to avoid BN_mod, I have an alternate version lying
around:

First, BN_set_bit + bn_mod_lshift1_consttime as now to count up to 2*R.
Next, observe that 2*R = BN_to_montgomery(2) and R*R =
BN_to_montgomery(R) = BN_to_montgomery(2^r_bits) Also observe that
BN_mod_mul_montgomery only needs n0, not RR. Split the core of
BN_mod_exp_mont into its own function so the caller handles conversion.
Raise 2*R to the r_bits power to get 2^r_bits*R = R*R.

The advantage of that algorithm is that it is still constant-time, so we
only need one BN_MONT_CTX_new. Additionally, it avoids BN_mod which is
otherwise (almost, but the remaining links should be easy to cut) out of
the critical path for correctness. One less operation to worry about.

The disadvantage is that it is gives a 25% (RSA-2048) or 32% (RSA-4096)
slower RSA verification speed. I went with the BN_mod one for the time
being.

Before:
Did 9204 RSA 2048 signing operations in 10052053us (915.6 ops/sec)
Did 326000 RSA 2048 verify (same key) operations in 10028823us (32506.3 ops/sec)
Did 50830 RSA 2048 verify (fresh key) operations in 10033794us (5065.9 ops/sec)
Did 1269 RSA 4096 signing operations in 10019204us (126.7 ops/sec)
Did 88435 RSA 4096 verify (same key) operations in 10031129us (8816.1 ops/sec)
Did 14552 RSA 4096 verify (fresh key) operations in 10053411us (1447.5 ops/sec)

After:
Did 9150 RSA 2048 signing operations in 10022831us (912.9 ops/sec)
Did 322000 RSA 2048 verify (same key) operations in 10028604us (32108.2 ops/sec)
Did 289000 RSA 2048 verify (fresh key) operations in 10017205us (28850.4 ops/sec)
Did 1270 RSA 4096 signing operations in 10072950us (126.1 ops/sec)
Did 87480 RSA 4096 verify (same key) operations in 10036328us (8716.3 ops/sec)
Did 80730 RSA 4096 verify (fresh key) operations in 10073614us (8014.0 ops/sec)

Change-Id: Ie8916d1634ccf8513ceda458fa302f09f3e93c07
Reviewed-on: https://boringssl-review.googlesource.com/27287
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>
2018-04-20 20:50:15 +00:00