SIWE_GO: Edge cases failing

Ok so at Tally we use Golang in the backend to do some tasks. And part of the signin is handled by it. But the code of the library : siwe_go is not working as intended but js counterpart is, bellow I'm adding tests cases to showcase it.

Story

Hi,

Arthur from Tally here. And we are using 'siwe-go' in the backend to authenticate SIWE requests. We noticed that it did not seem to work for users signing with Ledger+Metamask. I've put together some unit tests that duplicate the error.

You'll see that the javascript tests validate the signature, but the go tests for the same signature do not. We're not super familiar with how the cryptography works here. Do you know what the problem might be? We're looking for some help to fix the issue.

Happy to provide more context if that's helpful!

Replicate the issue.

Ok so a ledger signin is failing in siwe-go but not in siwe-js, to replicate the bug please, follow the next steps:

1. Clone this repository.

   git clone https://github.com/afa7789/siwe_go.git siwe_go_tally && cd siwe_go_tally

2. Recursively clone sub repositories.

   git submodule update --init --recursive

3. Copy both of this cases to the test files:

Run the patch files to make the changes needed in the test files:

	patch siwe-js/test/parsing_positive.json -i patches/parsing_positive.patch
	patch siwe-js/test/verification_positive.json -i patches/verification_positive.patch

Or you can copy and paste from here:

siwe-js/test/parsing_positive.json

    "tally_example": {
        "message": "www.tally.xyz wants you to sign in with your Ethereum account:\n0xc95EB884FE852e241D409234bfC7045CB9E31BD7\n\nSign in with Ethereum to Tally\n\nURI: https://tally.xyz\nVersion: 1\nChain ID: 1\nNonce: 15050747\nIssued At: 2022-06-30T14:08:51.382Z",
        "fields": {
            "domain": "www.tally.xyz",
            "address": "0xc95EB884FE852e241D409234bfC7045CB9E31BD7",
            "statement": "Sign in with Ethereum to Tally",
            "uri": "https://tally.xyz",
            "version": "1",
            "chainId": 1,
            "nonce": "15050747",
            "issuedAt": "2022-06-30T14:08:51.382Z"
        }
    }

siwe-js/test/verification_positive.json

	"tally_example": {
		"domain": "www.tally.xyz",
		"address": "0xc95EB884FE852e241D409234bfC7045CB9E31BD7",
		"statement": "Sign in with Ethereum to Tally",
		"uri": "https://tally.xyz",
		"version": "1",
		"chainId": 1,
		"nonce": "15050747",
		"issuedAt": "2022-06-30T14:08:51.382Z",
		"signature": "0x8c46b6eb8505939892d8e9b075f89f8277321b17b993151f37810cdda38cce6f4a85909d2b53e6a14629c74c0ac38bf4becde78ee5b2529812bf6cceaf7b2a2501"
	}

4. Install everything in the js package just to be sure it will work.

	pushd siwe-js
	npm install
	npm install --dev # not sure if needed.
	pushd packages/siwe
	npm install
	npm install --dev # not sure if needed.
	popd
	pushd packages/siwe-parser
	npm install
	npm install --dev # not sure if needed.
	popd
	popd

5. Run the tests in siwe_js and see that it works.

	pushd siwe-js
	npx jest
	popd

Run then more separated to see the tally example being printed as ok.

	pushd siwe-js/packages/siwe-parser
	npx jest
	popd

	pushd siwe-js/packages/siwe
	npx jest
	popd

Results:

Round Trip
	✓ Generates a Successfully Verifying message: tally_example (367 ms)
###
Message Generation
    ✓ Generates message successfully: tally_example (20 ms)
###
Message verification
	✓ Verificates message successfully: tally_example (288 ms)
###
Successfully parses with RegExp Client
    ✓ Parses message successfully: tally_example (8 ms)
###
Successfully parses with ABNF Client
    ✓ Parses message successfully: tally_example (216 ms)

6. Run the tests in siwe_go and see that it fails.

	go test -v .
	# or more specifically:
	go test -v -timeout 30s -run ^TestGlobalTestVector$

Error output:

The error we are getting is Invalid signature recovery byte

=== RUN   TestGlobalTestVector
    siwe_test.go:378: 
                Error Trace:    siwe_test.go:378
                                                        siwe_test.go:411
                Error:          Expected nil, but got: &siwe.InvalidSignature{string:"Invalid signature recovery byte"}
                Test:           TestGlobalTestVector
                Messages:       tally_example
--- FAIL: TestGlobalTestVector (0.00s)
FAIL
exit status 1
FAIL    github.com/spruceid/siwe-go     0.020s