fix and verify compressed argument in _eckey_pubkey_serialize calls
#300
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
In several calls of the internal function `secp256k1_eckey_pubkey_serialize`, the public API flag `SECP256K1_EC_COMPRESSED` is passed, which is meant to be only used for the public function `secp256k1_ec_pubkey_serialize`. It works as intended in all of those cases (it wouldn't for `..._UNCOMPRESSED` though), but it's still kind of a type mismatch that can't be detected by the compiler. To avoid cases like this in the future, a VERIFY_CHECK is added that the `compressed` parameter needs to be either 0 or 1.
|
LGTM |
| } | ||
|
|
||
| static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *pub, size_t *size, int compressed) { | ||
| VERIFY_CHECK(compressed == 0 || compressed == 1); |
There was a problem hiding this comment.
Not sure if we want to touch this upstream file. It's also a nice goal to keep the diff to upstream minimal. Ideally, the diff to upstream would just be added modules and changes to build system, README, etc... But yeah, we've modified upstream files in the past. If we think that this is a reasonable change, we could PR it to upstream, of course.
Same is true for the modification to secp256k1.c
There was a problem hiding this comment.
We should just rebase on upstream's musig module now.
theStack
added a commit
to theStack/secp256k1
that referenced
this pull request
Dec 2, 2024
Due to similarity to the public API function `secp256k1_ec_pubkey_serialize`, public API flags like `SECP256K1_EC_COMPRESSED` are sometimes mistakingly passed to newly proposed code (this is currently the case for several modules in secp256k1-zkp, see BlockstreamResearch/secp256k1-zkp#300). which is currently not detected. To avoid this in the future, a VERIFY_CHECK is added to check that the `compressed` argument is either 0 or 1.
real-or-random
added a commit
to bitcoin-core/secp256k1
that referenced
this pull request
Feb 24, 2025
…serialize` 1823594 Verify `compressed` argument in `secp256k1_eckey_pubkey_serialize` (Sebastian Falbesoner) Pull request description: Due to similarity to the public API function `secp256k1_ec_pubkey_serialize`, public API flags like `SECP256K1_EC_COMPRESSED` are sometimes mistakingly passed to `secp256k1_eckey_pubkey_serialize` in newly proposed code (this is currently the case for several modules in secp256k1-zkp, see BlockstreamResearch/secp256k1-zkp#300), which is currently not detected. To avoid this in the future, a VERIFY_CHECK is added to check that the `compressed` argument is either 0 or 1. ACKs for top commit: real-or-random: utACK 1823594 stratospher: ACK 1823594. Got tests failures when passing public API flags to `secp256k1_eckey_pubkey_serialize`. Tree-SHA512: ca542afc87f33e436ba33dc55b285dfe3759007c446ef94503bc1044c7a0a7f7b2208ae82e2c9743fc5fa38cf386127f3fbfa02d2c242f28fab3041ee46f153b
|
Closing this, as a corresponding PR was opened and merged in upstream (see bitcoin-core/secp256k1#1642), i.e. it will be available here once a rebase on v0.7.0 (or later) is done. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
In several calls of the internal function
secp256k1_eckey_pubkey_serialize, the public API flagSECP256K1_EC_COMPRESSEDis passed, which is meant to be only used for the public functionsecp256k1_ec_pubkey_serialize. It works as intended in all of those cases (it wouldn't forSECP256K1_EC_UNCOMPRESSEDthough), but it's still kind of a type mismatch that can't be detected by the compiler. To avoid cases like this in the future, a VERIFY_CHECK is added that thecompressedparameter needs to be either 0 or 1.