From c36136af9888356f8d85ef893d4777266400d36f Mon Sep 17 00:00:00 2001
From: Kevin Pita <kpita@peersyst.com>
Date: Tue, 24 Feb 2026 13:25:10 +0100
Subject: [PATCH] refactor(address-codec): set ed25519 family seed prefix

---
 address-codec/codec.go     |  8 +++-----
 pkg/crypto/ed25519.go      | 10 +++++-----
 pkg/crypto/ed25519_test.go |  2 +-
 pkg/crypto/secp256k1.go    | 14 ++++++--------
 pkg/crypto/types.go        |  2 +-
 5 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/address-codec/codec.go b/address-codec/codec.go
index bc8d1099..b32573f1 100644
--- a/address-codec/codec.go
+++ b/address-codec/codec.go
@@ -118,12 +118,10 @@ func EncodeSeed(entropy []byte, encodingType interfaces.CryptoImplementation) (s
 		return "", &EncodeLengthError{Instance: "Entropy", Input: len(entropy), Expected: FamilySeedLength}
 	}
 
-	if encodingType == crypto.ED25519() {
-		prefix := []byte{0x01, 0xe1, 0x4b}
-		return Encode(entropy, prefix, FamilySeedLength)
+	if ed25519 := crypto.ED25519(); encodingType == ed25519 {
+		return Encode(entropy, ed25519.FamilySeedPrefix(), FamilySeedLength)
 	} else if secp256k1 := crypto.SECP256K1(); encodingType == secp256k1 {
-		prefix := []byte{secp256k1.FamilySeedPrefix()}
-		return Encode(entropy, prefix, FamilySeedLength)
+		return Encode(entropy, secp256k1.FamilySeedPrefix(), FamilySeedLength)
 	}
 	return "", errors.New("encoding type must be `ed25519` or `secp256k1`")
 
diff --git a/pkg/crypto/ed25519.go b/pkg/crypto/ed25519.go
index 7b47ae77..0a912642 100644
--- a/pkg/crypto/ed25519.go
+++ b/pkg/crypto/ed25519.go
@@ -13,13 +13,13 @@ const (
 )
 
 var (
-	_ Algorithm = &ED25519CryptoAlgorithm{}
+	_                       Algorithm = &ED25519CryptoAlgorithm{}
+	ed25519FamilySeedPrefix           = []byte{0x01, 0xe1, 0x4b}
 )
 
 // ED25519CryptoAlgorithm is the implementation of the ED25519 cryptographic algorithm.
 type ED25519CryptoAlgorithm struct {
-	prefix           byte
-	familySeedPrefix byte
+	prefix byte
 }
 
 // ED25519 returns the ED25519 cryptographic algorithm.
@@ -35,8 +35,8 @@ func (c ED25519CryptoAlgorithm) Prefix() byte {
 }
 
 // FamilySeedPrefix returns the family seed prefix for the ED25519 cryptographic algorithm.
-func (c ED25519CryptoAlgorithm) FamilySeedPrefix() byte {
-	return c.familySeedPrefix
+func (c ED25519CryptoAlgorithm) FamilySeedPrefix() []byte {
+	return ed25519FamilySeedPrefix
 }
 
 // DeriveKeypair derives a keypair from a seed.
diff --git a/pkg/crypto/ed25519_test.go b/pkg/crypto/ed25519_test.go
index dc277459..ef510a5f 100644
--- a/pkg/crypto/ed25519_test.go
+++ b/pkg/crypto/ed25519_test.go
@@ -11,7 +11,7 @@ func TestED25519_Prefix(t *testing.T) {
 }
 
 func TestED25519_FamilySeedPrefix(t *testing.T) {
-	require.Zero(t, ED25519().FamilySeedPrefix())
+	require.Equal(t, ed25519FamilySeedPrefix, ED25519().FamilySeedPrefix())
 }
 
 func TestED25519DeriveKeypair(t *testing.T) {
diff --git a/pkg/crypto/secp256k1.go b/pkg/crypto/secp256k1.go
index e6c7b85f..e708d9a5 100644
--- a/pkg/crypto/secp256k1.go
+++ b/pkg/crypto/secp256k1.go
@@ -14,25 +14,23 @@ import (
 const (
 	// SECP256K1 prefix - value is 0
 	secp256K1Prefix byte = 0x00
-	// SECP256K1 family seed prefix - value is 33
-	secp256K1FamilySeedPrefix byte = 0x21
 )
 
 var (
 	_ Algorithm = SECP256K1CryptoAlgorithm{}
+	// SECP256K1 family seed prefix - value is 33
+	secp256K1FamilySeedPrefix = []byte{0x21}
 )
 
 // SECP256K1CryptoAlgorithm is the implementation of the SECP256K1 algorithm.
 type SECP256K1CryptoAlgorithm struct {
-	prefix           byte
-	familySeedPrefix byte
+	prefix byte
 }
 
 // SECP256K1 returns a new SECP256K1CryptoAlgorithm instance.
 func SECP256K1() SECP256K1CryptoAlgorithm {
 	return SECP256K1CryptoAlgorithm{
-		prefix:           secp256K1Prefix,
-		familySeedPrefix: secp256K1FamilySeedPrefix,
+		prefix: secp256K1Prefix,
 	}
 }
 
@@ -42,8 +40,8 @@ func (c SECP256K1CryptoAlgorithm) Prefix() byte {
 }
 
 // FamilySeedPrefix returns the family seed prefix for the SECP256K1 algorithm.
-func (c SECP256K1CryptoAlgorithm) FamilySeedPrefix() byte {
-	return c.familySeedPrefix
+func (c SECP256K1CryptoAlgorithm) FamilySeedPrefix() []byte {
+	return secp256K1FamilySeedPrefix
 }
 
 // deriveScalar derives a scalar from a seed.
diff --git a/pkg/crypto/types.go b/pkg/crypto/types.go
index 0ad37cf1..1dd1a806 100644
--- a/pkg/crypto/types.go
+++ b/pkg/crypto/types.go
@@ -3,5 +3,5 @@ package crypto
 // Algorithm defines the interface for cryptographic algorithms used in XRPL key generation and signing.
 type Algorithm interface {
 	Prefix() byte
-	FamilySeedPrefix() byte
+	FamilySeedPrefix() []byte
 }