Apparently clang 15 is able to compile our cmov code into a branch,
at least for fe_cmov and fe_storage_cmov. This commit makes the
condition volatile in all cmov implementations (except ge but that
one only calls into the fe impls).
This is just a quick fix. We should still look into other methods,
e.g., asm and #457. We should also consider not caring about
constant-time in scalar_low_impl.h
We should also consider testing on very new compilers in nightly CI,
see https://github.com/bitcoin-core/secp256k1/pull/864#issuecomment-769211867
a1ec2bb67b musig: add test for signing with wrong secnonce for a keypair (Jonas Nick)
bd57a017aa musig: include pubkey in secnonce and compare when signing (Jonas Nick)
Pull request description:
Builds on #211.
This PR implements a defense-in-depth measure that is specified in BIP-MuSig2. In fact, it revealed a bug in the `scriptless_atomic_swap` test.
ACKs for top commit:
real-or-random:
ACK a1ec2bb67b
Tree-SHA512: dfd54a07c13648e6a7163962bb516cc4ec3a25e4534da2c14a593e2da0f3779eb9b84bfa12ffd94676bb3f6ab86a323e7ec7dee938fd870f36882fee0181ca05
b43dd83b43 musig: add missing static keyword to function (Jonas Nick)
068e6a036a musig: add test vectors from BIP MuSig (Jonas Nick)
36621d13be musig: update to BIP v1.0.0-rc.2 "Add ''pk'' arg to ''NonceGen''" (Jonas Nick)
d717a4980b musig: update to BIP v0.8 "Switch from X-only to plain pk inputs." (Jonas Nick)
304f1bc96d extrakeys: add pubkey_sort test vectors from BIP MuSig2 (Jonas Nick)
ae89051547 extrakeys: replace xonly_sort with pubkey_sort (Jonas Nick)
98242fcdd9 extrakeys: add secp256k1_pubkey_cmp (Jonas Nick)
73d5b6654d musig: update to BIP v0.7.0 (NonceGen) (Jonas Nick)
060887e9d7 musig: update to BIP v0.5.1 "Rename ordinary tweaking to plain" (Jonas Nick)
cbe2815633 musig: update to BIP v0.4 "Allow the output of NonceAgg to be inf" (Jonas Nick)
206017d67d musig: update to BIP v0.3 (NonceGen) (Jonas Nick)
d800dd55db musig: remove test vectors (Jonas Nick)
Pull request description:
Version 1.0.0-rc.3 of BIP MuSig2 can be found [here](https://github.com/jonasnick/bips/pull/75). This PR does _not_ implement the following optional features that have been added to BIP MuSig2:
- variable length messages
- deterministic signing
- identifiable aborts
The PR also does _not_ yet change the `secnonce` structure to also contain the signer's public key (which would also imply changing the seckey argument in `sign` to a keypair). Additionally, we may want to rename some things in the future to be more consistent with the BIP (e.g. keyagg_cache vs. keyagg_ctx, applytweak vs. tweak_add).
ACKs for top commit:
ariard:
Light Code Review ACK b43dd83b, mostly looks on how the user API will make sense for Lightning, thanks for the answers!
real-or-random:
ACK b43dd83b43
Tree-SHA512: 9b1410951b55a1b0e6590b8c302052996d1fb6d9771765498b4282ff68b44ab0d6add8144c9330217b682ec5a93508b5546099db9a1f2c865f99253010dd76f4
- 0.7.0: Change ''NonceGen'' such that output when message is not present is different from when message is present but has length 0.
- 0.6.0: Change order of arguments and serialization of the message in the ''NonceGen'' hash function
Silence a compiler warning about an unitialized use of a scalar in case
the user tries to provide a 0-length list of commitments.
Also ensures that commitments have normalized field elements when they
are loaded into ges.
