dkforest

commit 232d195743583b25398775ffc305eaafa0662ae4
parent 801554dbaf413cc9a5ba81279536a54c6d908c08
Author: n0tr1v <n0tr1v@protonmail.com>
Date:   Sun, 29 Jan 2023 05:54:52 -0800

utils fn to verify a tor ed25519 signature

Diffstat:
M
pkg/utils/utils.go
 | 
19
+++++++++++++++++++

1 file changed, 19 insertions(+), 0 deletions(-)
diff --git a/pkg/utils/utils.go b/pkg/utils/utils.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"crypto/aes"
 	"crypto/cipher"
+	"crypto/ed25519"
 	"crypto/md5"
 	cryptoRand "crypto/rand"
 	"crypto/rsa"
@@ -14,6 +15,7 @@ import (
 	"dkforest/pkg/bfchroma"
 	bf "dkforest/pkg/blackfriday/v2"
 	"dkforest/pkg/utils/crypto"
+	"encoding/base32"
 	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
@@ -1077,3 +1079,20 @@ func (r Renderer) RenderHeader(w io.Writer, ast *bf.Node) {
 func (r Renderer) RenderFooter(w io.Writer, ast *bf.Node) {
 	r.Base.RenderFooter(w, ast)
 }
+
+func VerifyTorSign(onionAddr, msg, pemSig string) bool {
+	block, _ := pem.Decode([]byte(pemSig))
+	if block == nil {
+		return false
+	}
+	sig := block.Bytes
+	pub := identityKeyFromAddress(onionAddr)
+	return ed25519.Verify(pub, []byte(msg), sig)
+}
+
+func identityKeyFromAddress(onionAddr string) ed25519.PublicKey {
+	trimmedAddr := strings.TrimSuffix(onionAddr, ".onion")
+	upperAddr := strings.ToUpper(trimmedAddr)
+	decodedAddr, _ := base32.StdEncoding.DecodeString(upperAddr)
+	return decodedAddr[:32]
+}