make libsecp256k1 available with a build tag.

libsecp256k1/README.md

@@ -1,33 +0,0 @@
-This wraps [libsecp256k1](https://github.com/bitcoin-core/secp256k1) with `cgo`.
-
-It doesn't embed the library or anything smart like that because I don't know how to do it, so you must have it installed in your system.
-
-It is faster than the pure Go version:
-
-```
-goos: linux
-goarch: amd64
-pkg: github.com/nbd-wtf/go-nostr/libsecp256k1
-cpu: AMD Ryzen 3 3200G with Radeon Vega Graphics
-BenchmarkSignatureVerification/btcec-4         	     145	   7873130 ns/op	  127069 B/op	     579 allocs/op
-BenchmarkSignatureVerification/libsecp256k1-4  	     502	   2314573 ns/op	  112241 B/op	     392 allocs/op
-```
-
-To use it manually, just import. To use it inside the automatic verification that happens for subscriptions, set it up with a `SimplePool`:
-
-```go
-pool := nostr.NewSimplePool()
-pool.SignatureChecker = func (evt nostr.Event) bool {
-	ok, _ := libsecp256k1.CheckSignature(evt)
-	return ok
-}
-```
-
-Or directly to the `Relay`:
-
-```go
-relay := nostr.RelayConnect(context.Background(), "wss://relay.nostr.com", nostr.WithSignatureChecker(func (evt nostr.Event) bool {
-	ok, _ := libsecp256k1.CheckSignature(evt)
-	return ok
-}))
-```

libsecp256k1/benchmark_test.go

@@ -1,34 +0,0 @@
-package libsecp256k1
-
-import (
-	"encoding/json"
-	"testing"
-
-	"github.com/nbd-wtf/go-nostr"
-	"github.com/nbd-wtf/go-nostr/test_common"
-)
-
-func BenchmarkSignatureVerification(b *testing.B) {
-	events := make([]*nostr.Event, len(test_common.NormalEvents))
-	for i, jevt := range test_common.NormalEvents {
-		evt := &nostr.Event{}
-		json.Unmarshal([]byte(jevt), evt)
-		events[i] = evt
-	}
-
-	b.Run("btcec", func(b *testing.B) {
-		for i := 0; i < b.N; i++ {
-			for _, evt := range events {
-				evt.CheckSignature()
-			}
-		}
-	})
-
-	b.Run("libsecp256k1", func(b *testing.B) {
-		for i := 0; i < b.N; i++ {
-			for _, evt := range events {
-				CheckSignature(evt)
-			}
-		}
-	})
-}

libsecp256k1/bip340.go

@@ -1,51 +0,0 @@
-package libsecp256k1
-
-/*
-#cgo LDFLAGS: -lsecp256k1
-#include <secp256k1.h>
-#include <secp256k1_schnorrsig.h>
-#include <secp256k1_extrakeys.h>
-*/
-import "C"
-
-import (
-	"crypto/rand"
-	"errors"
-	"unsafe"
-)
-
-var globalSecp256k1Context *C.secp256k1_context
-
-func init() {
-	globalSecp256k1Context = C.secp256k1_context_create(C.SECP256K1_CONTEXT_SIGN | C.SECP256K1_CONTEXT_VERIFY)
-	if globalSecp256k1Context == nil {
-		panic("failed to create secp256k1 context")
-	}
-}
-
-func Sign(msg [32]byte, sk [32]byte) ([64]byte, error) {
-	var sig [64]byte
-
-	var keypair C.secp256k1_keypair
-	if C.secp256k1_keypair_create(globalSecp256k1Context, &keypair, (*C.uchar)(unsafe.Pointer(&sk[0]))) != 1 {
-		return sig, errors.New("failed to parse private key")
-	}
-
-	var random [32]byte
-	rand.Read(random[:])
-
-	if C.secp256k1_schnorrsig_sign32(globalSecp256k1Context, (*C.uchar)(unsafe.Pointer(&sig[0])), (*C.uchar)(unsafe.Pointer(&msg[0])), &keypair, (*C.uchar)(unsafe.Pointer(&random[0]))) != 1 {
-		return sig, errors.New("failed to sign message")
-	}
-
-	return sig, nil
-}
-
-func Verify(msg [32]byte, sig [64]byte, pk [32]byte) bool {
-	var xonly C.secp256k1_xonly_pubkey
-	if C.secp256k1_xonly_pubkey_parse(globalSecp256k1Context, &xonly, (*C.uchar)(unsafe.Pointer(&pk[0]))) != 1 {
-		return false
-	}
-
-	return C.secp256k1_schnorrsig_verify(globalSecp256k1Context, (*C.uchar)(unsafe.Pointer(&sig[0])), (*C.uchar)(unsafe.Pointer(&msg[0])), 32, &xonly) == 1
-}

libsecp256k1/signverify_test.go

@@ -1,20 +0,0 @@
-package libsecp256k1
-
-import (
-	"encoding/json"
-	"testing"
-
-	"github.com/nbd-wtf/go-nostr"
-	"github.com/nbd-wtf/go-nostr/test_common"
-	"github.com/stretchr/testify/assert"
-)
-
-func TestEventVerification(t *testing.T) {
-	for _, jevt := range test_common.NormalEvents {
-		evt := &nostr.Event{}
-		json.Unmarshal([]byte(jevt), evt)
-		ok, _ := CheckSignature(evt)
-		shouldBe, _ := evt.CheckSignature()
-		assert.Equal(t, ok, shouldBe, "%s signature must be %s", jevt, shouldBe)
-	}
-}

libsecp256k1/verify.go

@@ -1,26 +0,0 @@
-package libsecp256k1
-
-import (
-	"crypto/sha256"
-	"encoding/hex"
-	"fmt"
-
-	"github.com/nbd-wtf/go-nostr"
-)
-
-func CheckSignature(evt *nostr.Event) (bool, error) {
-	var pk [32]byte
-	_, err := hex.Decode(pk[:], []byte(evt.PubKey))
-	if err != nil {
-		return false, fmt.Errorf("event pubkey '%s' is invalid hex: %w", evt.PubKey, err)
-	}
-
-	var sig [64]byte
-	_, err = hex.Decode(sig[:], []byte(evt.Sig))
-	if err != nil {
-		return false, fmt.Errorf("event signature '%s' is invalid hex: %w", evt.Sig, err)
-	}
-
-	msg := sha256.Sum256(evt.Serialize())
-	return Verify(msg, sig, pk), nil
-}