f431b3f28a valgrind_ctime_test: Add schnorrsig_sign (Jonas Nick)
16ffa9d97c schnorrsig: Add taproot test case (Jonas Nick)
8dfd53ee3f schnorrsig: Add benchmark for sign and verify (Jonas Nick)
4e43520026 schnorrsig: Add BIP-340 compatible signing and verification (Jonas Nick)
7332d2db6b schnorrsig: Add BIP-340 nonce function (Jonas Nick)
7a703fd97d schnorrsig: Init empty experimental module (Jonas Nick)
eabd9bc46a Allow initializing tagged sha256 (Jonas Nick)
6fcb5b845d extrakeys: Add keypair_xonly_tweak_add (Jonas Nick)
58254463f9 extrakeys: Add keypair struct with create, pub and pub_xonly (Jonas Nick)
f0010349b8 Separate helper functions for pubkey_create and seckey_tweak_add (Jonas Nick)
910d9c284c extrakeys: Add xonly_pubkey_tweak_add & xonly_pubkey_tweak_add_test (Jonas Nick)
176bfb1110 Separate helper function for ec_pubkey_tweak_add (Jonas Nick)
4cd2ee474d extrakeys: Add xonly_pubkey with serialize, parse and from_pubkey (Jonas Nick)
47e6618e11 extrakeys: Init empty experimental module (Jonas Nick)
3e08b02e2a Make the secp256k1_declassify argument constant (Jonas Nick)
Pull request description:
This PR implements signing, verification and batch verification as described in [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki) in an experimental module named `schnorrsig`. It includes the test vectors and a benchmarking tool.
This PR also adds a module `extrakeys` that allows [BIP-341](https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki)-style key tweaking.
(Adding ChaCha20 as a CSPRNG and batch verification was moved to PR #760).
In order to enable the module run `./configure` with `--enable-experimental --enable-module-schnorrsig`.
Based on apoelstra's work.
ACKs for top commit:
gmaxwell:
ACK f431b3f28a (exactly matches the previous post-fixup version which I have already reviewed and tested)
sipa:
ACK f431b3f28a
real-or-random:
ACK f431b3f28a careful code review
Tree-SHA512: e15e849c7bb65cdc5d7b1d6874678e275a71e4514de9d5432ec1700de3ba92aa9f381915813f4729057af152d90eea26aabb976ed297019c5767e59cf0bbc693
47a7b8382f Clear field elements when writing infinity (Elichai Turkel)
61d1ecb028 Added test with additions resulting in infinity (Elichai Turkel)
Pull request description:
Currently if `secp256k1_gej_add_var` / `secp256k1_gej_add_ge_var` /` secp256k1_gej_add_zinv_var` receive `P + (-P)` it will set `gej->infinity = 1` but doesn't call initialize the field elements.
Notice that this is the only branch in the function that results in an uninitialized output.
By using `secp256k1_gej_set_infinity()` it will set the field elements to zero while also setting the infinity flag.
I also added a test that fails with valgrind on current master but passes with the fix.
EDIT: This isn't a bug or something necessary, I just personally found this helpful.
ACKs for top commit:
real-or-random:
ACK 47a7b8382f
Tree-SHA512: cdc2efc242a1b04b4f081183c07d4b2602cdba705e6b30b548df4e115e54fb97691f4b1a28f142f02d5e523c020721337a297b17d732acde147b910f5c53bd0a
8bc6aeffa9 Add SHA256 selftest (Pieter Wuille)
5e5fb28b4a Use additional system macros to figure out endianness (Pieter Wuille)
Pull request description:
These are all the architecture macros I could find with known endianness. Use those as a fallback when __BYTE_ORDER__ isn't available.
See https://github.com/bitcoin-core/secp256k1/pull/787#issuecomment-673764652
It also adds a SHA256 selftest, so that improperly overriding the endianness detection will be detected at runtime.
ACKs for top commit:
real-or-random:
ACK 8bc6aeffa9 I read the diff, and tested that the self-test passes/fails with/without the correct endianness setting
gmaxwell:
ACK 8bc6aeffa9 looks good and I also ran the tests on MIPS-BE and verified that forcing it to LE makes the runtime test fail.
Tree-SHA512: aca4cebcd0715dcf5b58f5763cb4283af238987f43bd83a650e38e127f348131692b2eed7ae5b2ae96046d9b971fc77c6ab44467689399fe470a605c3458ecc5
60f7f2de5d Don't assume that ALIGNMENT > 1 in tests (Tim Ruffing)
ada6361dec Use ROUND_TO_ALIGN in scratch_create (Jonas Nick)
8ecc6ce50e Add check preventing rounding to alignment from wrapping around in scratch_alloc (Jonas Nick)
4edaf06fb0 Add check preventing integer multiplication wrapping around in scratch_max_allocation (Jonas Nick)
Pull request description:
This PR increases the general robustness of scratch spaces. It does not fix an existing vulnerability because scratch spaces aren't used anywhere in master. Additionally, it must be prevented anyway that an attacker has (indirect) control over the arguments touched in this PR.
ACKs for top commit:
sipa:
ACK 60f7f2de5d
Tree-SHA512: ecdd794b55a01d1d6d24098f3abff34cb8bb6f33737ec4ec93714aa631c9d397b213cc3603a916ad79f4b09d6b2f8973bf87fc07b81b25a530cc72c4dbafaba9
0dccf98a21 Use preprocessor macros instead of autoconf to detect endianness (Tim Ruffing)
Pull request description:
This does not fix any particular issue but it's preferable to not
rely on autoconf. This avoids endianness mess for users on BE hosts
if they use their build without autoconf.
The macros are carefully written to err on the side of the caution,
e.g., we #error if the user manually configures a different endianness
than what we detect.
Supersedes #770 .
ACKs for top commit:
sipa:
ACK 0dccf98a21
gmaxwell:
ACK 0dccf98a21
Tree-SHA512: 6779458de5cb6eaef2ac37f9d4b8fa6c9b299f58f6e5b72f2b0d7e36c12ea06074e483acfb85085a147e0f4b51cd67d897f61a67250ec1cea284a0f7680eb2e8
This does not fix any particular issue but it's preferable to not
rely on autoconf. This avoids endianness mess for users on BE hosts
if they use their build without autoconf.
The macros are carefully written to err on the side of the caution,
e.g., we #error if the user manually configures a different endianness
than what we detect.
Instead of supporting configuration of the field and scalar size independently,
both are now controlled by the availability of a 64x64->128 bit multiplication
(currently only through __int128). This is autodetected from the C code through
__SIZEOF_INT128__, but can be overridden using configure's
--with-test-override-wide-multiply, or by defining
USE_FORCE_WIDEMUL_{INT64,INT128} manually.
So far this has not been needed, as it's only used by the static precomputation
which always builds with 32-bit fields.
This prepares for the ability to have __int128 detected on the C side, breaking
that restriction.
67a429f31f Suppress a harmless variable-time optimization by clang in _int_cmov (Tim Ruffing)
5b196338f0 Remove redundant "? 1 : 0" after comparisons in scalar code (Tim Ruffing)
Pull request description:
Attempt at resolving #771 .
This surprisingly seems to improve the situation at least for the compilers available on godbolt.
ACKs for top commit:
gmaxwell:
ACK 67a429f31f
elichai:
tACK 67a429f31f
Tree-SHA512: ee8b0c86831ec8c3d5a9abcad773ed8a0f267e5c47012e4e1423b10a64c26b4cf6e3c466c3df765ba7e636787a3fe134d633926d67b599287f12c51be924f478
37dba329c6 Remove unnecessary sign variable from wnaf_const (Jonas Nick)
6bb0b77e15 Fix test_constant_wnaf for -1 and add a test for it. (Jonas Nick)
Pull request description:
There currently is a single branch in the `ecmul_const` function that is not being exercised by the tests. This branch is unreachable and therefore I'm suggesting to remove it.
For your convenience the paper the wnaf algorithm can be found [here (The Width-w NAF Method Provides Small Memory and Fast Elliptic Scalar Multiplications Secure against Side Channel Attacks)](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.563.1267&rep=rep1&type=pdf). Similarly, unless I'm missing something important, I don't see how their algorithm needs to consider `sign(u[i-1])` unless `d` can be negative - which doesn't make much sense to me either.
ACKs for top commit:
real-or-random:
ACK 37dba329c6 I verified the correctness of the change and claimed invariant by manual inspection. I tested the code, both with 32bit and 64bit scalars.
Tree-SHA512: 9db45f76bd881d00a81923b6d2ae1c3e0f49a82a5d55347f01e1ce4e924d9a3bf55483a0697f25039c327e33edca6796ba3205c068d9f2f99aa5d655e46b15be
7e3952ae82 Clarify documentation of tweak functions. (Jonas Nick)
89853a0f2e Make tweak function documentation more consistent. (Jonas Nick)
41fc785602 Make ec_privkey functions aliases for ec_seckey_negate, ec_seckey_tweak_add and ec_seckey_mul (Jonas Nick)
22911ee6da Rename private key to secret key in public API (with the exception of function names) (Jonas Nick)
5a73f14d6c Mention that value is unspecified for In/Out parameters if the function returns 0 (Jonas Nick)
f03df0e6d7 Define valid ECDSA keys in the documentation of seckey_verify (Jonas Nick)
5894e1f1df Return 0 if the given seckey is invalid in privkey_negate, privkey_tweak_add and privkey_tweak_mul (Jonas Nick)
8f814cddb9 Add test for boundary conditions of scalar_set_b32 with respect to overflows (Jonas Nick)
3fec982608 Use scalar_set_b32_seckey in ecdsa_sign, pubkey_create and seckey_verify (Jonas Nick)
9ab2cbe0eb Add scalar_set_b32_seckey which does the same as scalar_set_b32 and also returns whether it's a valid secret key (Jonas Nick)
Pull request description:
Fixes#671. Supersedes #668.
This PR unifies handling of invalid secret keys by introducing a new function `scalar_set_b32_secret` which returns false if the b32 overflows or is 0. By using this in `privkey_{negate, tweak_add, tweak_mul}` these function will now return 0 if the secret key is invalid which matches the behavior of `ecdsa_sign` and `pubkey_create`.
Instead of deciding whether to zeroize the secret key on failure, I only added documentation for now that the value is undefined on failure.
ACKs for top commit:
real-or-random:
ACK 7e3952ae82 I read the diff carefully and tested the changes
apoelstra:
ACK 7e3952ae82
Tree-SHA512: 8e9a66799cd3b6ec1c3acb731d6778035417e3dca9300d840e2437346ff0ac94f0c9be4de20aa2fac9bb4ae2f8a36d4e6a34795a640b9cfbfee8311decb102f0
Before, test_constant_wnaf used scalar_cadd_bit to correct for the skew. But
this function does not correctly deal with overflows which is why num = -1
couldn't be tested.
This commit also adds tests for 0, 1/2 and 1/2-1 as they are corner cases
in constant_wnaf.
37ed51a7ea Make ecdsa_sig_sign constant-time again after reverting 25e3cfb (Tim Ruffing)
93d343bfc5 Revert "ecdsa_impl: replace scalar if-checks with VERIFY_CHECKs in ecdsa_sig_sign" (Tim Ruffing)
Pull request description:
ACKs for top commit:
elichai:
ACK 37ed51a7ea makes sense.
jonasnick:
ACK 37ed51a7ea
Tree-SHA512: 82b5b8e29f48e84fd7a0681b62923d3bd87d724b38ef18e8c7969b0dcc5a405ebb26c14b5c5f4c7ba0ccabd152d1531d217809d1daf40872fe0c1e079b55c64b
