x

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github.com/go-webauthn/x

Low level packages for github.com/go-webauthn/webauthn.

Forked Packages

Every package in this repository is a fork of an upstream source, carried in-tree rather than taken as a dependency. This document is the single record of where each one came from, so that outstanding upstream fixes can be found by diffing the recorded commit against the upstream branch.

Package	Upstream	Commit base	Local changes
crypto/blake256	decred/dcrd crypto/blake256	c32cc6f5cfc72b2b76a38e43d2a702f17e94d248	Import path rewrite; fixes
crypto/blake256/internal/compress	decred/dcrd crypto/blake256/internal/compress	d11d77828cd7ffb4e90b41f95bbf188f7d180e4a	Fixes
crypto/blake256/internal/_asm	decred/dcrd crypto/blake256/internal/_asm	0d2e94857b109d8bcf1056b3d5061ca90f0f8b94	Module path rewrite only
crypto/secp256k1	decred/dcrd dcrec/secp256k1	085eb08c6b1e3aec6a201fd5ac45c64a2daf9144	Import path rewrite; fixes
crypto/secp256k1/ecdsa	decred/dcrd dcrec/secp256k1/ecdsa	085eb08c6b1e3aec6a201fd5ac45c64a2daf9144	Import path rewrite only
encoding/asn1	golang/go src/encoding/asn1	3e43f48cb6311c3c459f5c7aa69ae7d28b7fc821	Substantial
revoke	cloudflare/cfssl	e6502bb7ffe4ee576227c9123a101deda248884c	Substantial

Each commit base is the most recent upstream commit to touch that path as of the fork, so a base older than the fork itself simply means upstream had not modified those files since.

Each section below ends with the git log command that lists the upstream changes since that base. The paths in those commands are upstream paths rather than paths in this repository, so each one must be run from a checkout of the upstream it targets: decred/dcrd for dcrec/secp256k1 and crypto/blake256, golang/go for src/encoding/asn1, and cloudflare/cfssl for revoke.

Local fixes to the dcrd forks

These are the only changes to the decred/dcrd sources beyond the import path rewrites. They are not carried upstream, so they must be reapplied on a resync. crypto/blake256/fork_test.go has no upstream counterpart and covers the first two.

Location	Change
blake256/hasher.go write	Compute the partial block guard in 64-bit arithmetic. A single write of 4 GiB truncated to uint32, skipped the pending block, and produced a wrong hash. The guard is extracted to needsPartialBlockFlush so it can be tested without a 4 GiB write.
blake256/hasher.go loadState	Reject a serialized state whose buffered byte count is not less than BlockSize, and decode into a local value so a rejected state cannot partially overwrite the receiver. Previously such a state panicked on the next write.
blake256/internal/compress	Enforce the documented minimum message length in both Blocks implementations. The amd64 assembly does not bounds check, so only the pure Go path panicked as documented. blocksGeneric itself returns without touching the chain value, so its comment now says the exported Blocks is what enforces the minimum.
blake256/internal/compress test vectors	Add two salted blockVecs entries derived from the salted vectors in hasher_test.go. Without them no salt reaches the SSE2, SSE4.1, or AVX compression paths, since TestBlocksAMD64 is the only test that forces each variant.
blake256/internal/compress/cpu_amd64.s	Declare supportsCPUID as $8-1 rather than $8-4; a bool result is one byte, and go vet rejects the mismatch on amd64.
secp256k1/doc.go	Drop the references to the excluded schnorr subpackage and to per-package README.md files, neither of which exist in this fork.
secp256k1/pubkey.go	Document the hybrid format bytes as 0x06/0x07 to match PubKeyFormatHybridEven and PubKeyFormatHybridOdd; the comment said 0x05/0x06.
secp256k1/error.go	Spell the curve secp256k1 in the Error doc comment.

crypto/secp256k1

Provides the secp256k1 curve used by the COSE ES256K algorithm and secp256k1 elliptic curve identifiers.

The schnorr subpackage, which implements EC-Schnorr-DCRv0, a signature scheme specific to Decred, is not included as it has no WebAuthn use. The commit base covers both this package and its ecdsa subpackage. Beyond the local fixes listed below, sources are unmodified apart from rewriting github.com/decred/dcrd/dcrec/secp256k1/v4 to github.com/go-webauthn/x/crypto/secp256k1 and github.com/decred/dcrd/crypto/blake256 to github.com/go-webauthn/x/crypto/blake256.

git log --oneline 085eb08c6b1e3aec6a201fd5ac45c64a2daf9144..master -- dcrec/secp256k1

crypto/blake256

The ecdsa test vectors of crypto/secp256k1 are computed over BLAKE-256 hashes, so upstream depends on this package. It is forked in rather than taken as a dependency to keep it out of this module's dependency graph. Beyond the local fixes listed below, sources are unmodified apart from rewriting github.com/decred/dcrd/crypto/blake256 to github.com/go-webauthn/x/crypto/blake256.

The internal/compress and internal/_asm subpackages record their own bases above because upstream last modified them earlier than the parent. The leading underscore of internal/_asm means the Go tool ignores that directory entirely, so the nested go.mod there and the avo dependency it pins are never built and form no part of this module; it is excluded from Renovate via ignorePaths in .renovaterc for the same reason.

git log --oneline c32cc6f5cfc72b2b76a38e43d2a702f17e94d248..master -- crypto/blake256

encoding/asn1

Unlike the crypto forks, this one diverges from upstream throughout rather than only in its import paths, so upstream changes cannot be applied wholesale:

• asn1.go is renamed to unmarshal.go and asn1_test.go to unmarshal_test.go.
• common.go, marshal.go, and unmarshal.go each carry local modifications threading the marshalling and unmarshalling options through the encoder and decoder.
• ecdsa.go, ecdsa_test.go, marshal_opts.go, and unmarshal_opts.go have no upstream counterpart.

git log --oneline 3e43f48cb6311c3c459f5c7aa69ae7d28b7fc821..master -- src/encoding/asn1

revoke

This package reached the repository in two hops, neither of which recorded the commit of the source it was taken from. Both source commits below were therefore reconstructed after the fact:

1. github.com/go-webauthn/revoke (now archived) took a snapshot of cloudflare/cfssl in its initial commit 1edcf14 on 2022-04-04. The newest cfssl commit on master at that point was e6502bb7ffe4ee576227c9123a101deda248884c (2022-01-19), which is therefore the upstream base.
2. This repository imported go-webauthn/revoke at dea760d7e233a1a959f1dc5e43f18fd3cd3607e1 (2023-02-09) in commit 9ec0dbc on 2023-02-15, the only difference being the doc comment reformatting gofmt applied in Go 1.19.

The fork flattens four separate cfssl packages into the single revoke package, so upstream changes must be traced per file rather than against one directory:

File	Upstream path	Last upstream change as of the base
revoke.go	revoke/revoke.go	f247e5b (2021-02-08)
err.go	errors/error.go	d0cbfb5 (2018-03-22)
helpers.go	helpers/helpers.go	a8591c3 (2021-09-15)
pkcs7.go	crypto/pkcs7/pkcs7.go	6ceae7b (2017-02-07)

doc.go, revoke_legacy.go, and revoke_modern.go have no upstream counterpart. The imported files differ from cfssl only by the package renames the flattening requires, the removal of the cfssl/log dependency and its logging calls, and the unqualified references those two changes imply. Local changes made since the import are in this repository's history under revoke/.

git log --oneline e6502bb7ffe4ee576227c9123a101deda248884c..master -- revoke errors/error.go helpers/helpers.go crypto/pkcs7