From b142964d3110a0a23c18ffefcbeea5ef6f271a43 Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Mon, 9 Sep 2019 20:04:35 -0400
Subject: [PATCH] Adds support for verifying ed25519 signatures, for secio

---
 libp2p/crypto/ed25519.py       | 29 +++++++++++++++++++++++++++++
 libp2p/crypto/serialization.py |  2 ++
 setup.py                       |  1 +
 3 files changed, 32 insertions(+)
 create mode 100644 libp2p/crypto/ed25519.py

diff --git a/libp2p/crypto/ed25519.py b/libp2p/crypto/ed25519.py
new file mode 100644
index 00000000..713e74b8
--- /dev/null
+++ b/libp2p/crypto/ed25519.py
@@ -0,0 +1,29 @@
+from Crypto.Hash import SHA256
+
+from libp2p.crypto.keys import KeyType, PublicKey
+from nacl.public import PublicKey as Ed255129PublicKeyImpl
+from nacl.signing import BadSignatureError, VerifyKey
+
+
+class Ed25519PublicKey(PublicKey):
+    def __init__(self, impl: Ed255129PublicKeyImpl) -> None:
+        self.impl = impl
+
+    def to_bytes(self) -> bytes:
+        return bytes(self.impl)
+
+    @classmethod
+    def from_bytes(cls, key_bytes: bytes) -> "Ed25519PublicKey":
+        return cls(Ed255129PublicKeyImpl(key_bytes))
+
+    def get_type(self) -> KeyType:
+        return KeyType.Ed25519
+
+    def verify(self, data: bytes, signature: bytes) -> bool:
+        verify_key = VerifyKey(self.to_bytes())
+        h = SHA256.new(data)
+        try:
+            verify_key.verify(h, signature)
+        except BadSignatureError:
+            return False
+        return True
diff --git a/libp2p/crypto/serialization.py b/libp2p/crypto/serialization.py
index dedcf85d..6bc686e3 100644
--- a/libp2p/crypto/serialization.py
+++ b/libp2p/crypto/serialization.py
@@ -1,3 +1,4 @@
+from libp2p.crypto.ed25519 import Ed25519PublicKey
 from libp2p.crypto.keys import KeyType, PrivateKey, PublicKey
 from libp2p.crypto.rsa import RSAPublicKey
 from libp2p.crypto.secp256k1 import Secp256k1PrivateKey, Secp256k1PublicKey
@@ -5,6 +6,7 @@ from libp2p.crypto.secp256k1 import Secp256k1PrivateKey, Secp256k1PublicKey
 key_type_to_public_key_deserializer = {
     KeyType.Secp256k1.value: Secp256k1PublicKey.from_bytes,
     KeyType.RSA.value: RSAPublicKey.from_bytes,
+    KeyType.Ed25519.value: Ed25519PublicKey.from_bytes,
 }
 
 key_type_to_private_key_deserializer = {
diff --git a/setup.py b/setup.py
index 6e6ad676..152a5b1a 100644
--- a/setup.py
+++ b/setup.py
@@ -41,6 +41,7 @@ setuptools.setup(
         "protobuf==3.9.0",
         "coincurve>=10.0.0,<11.0.0",
         "fastecdsa==1.7.4",
+        "pynacl==1.3.0",
     ],
     extras_require=extras_require,
     packages=setuptools.find_packages(exclude=["tests", "tests.*"]),