♻️ Add _Crypto.verifySignature

yenom · Sep 19, 2018 · 48c46ad · 48c46ad
1 parent 71539f6
commit 48c46ad
Show file tree

Hide file tree

Showing 3 changed files with 19 additions and 23 deletions.
diff --git a/BitcoinKit/BitcoinKitPrivate.h b/BitcoinKit/BitcoinKitPrivate.h
@@ -59,6 +59,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface _Crypto : NSObject
 + (NSData *)signMessage:(NSData *)message withPrivateKey:(NSData *)privateKey;
++ (BOOL)verifySignature:(NSData *)signature message:(NSData *)message  publicKey:(NSData *)publicKey;
 @end
-
 NS_ASSUME_NONNULL_END
diff --git a/BitcoinKit/BitcoinKitPrivate.m b/BitcoinKit/BitcoinKitPrivate.m
@@ -216,12 +216,28 @@ + (NSData *)signMessage:(NSData *)message withPrivateKey:(NSData *)privateKey {
     secp256k1_ecdsa_signature normalizedSignature;
     secp256k1_ecdsa_sign(ctx, &signature, message.bytes, privateKey.bytes, NULL, NULL);
     secp256k1_ecdsa_signature_normalize(ctx, &normalizedSignature, &signature);
-    size_t siglen = 128;
+    size_t siglen = 74;
     NSMutableData *der = [NSMutableData dataWithLength:siglen];
     secp256k1_ecdsa_signature_serialize_der(ctx, der.mutableBytes, &siglen, &normalizedSignature);
     der.length = siglen;
     secp256k1_context_destroy(ctx);
     return der;
 }
 
++ (BOOL)verifySignature:(NSData *)sigData message:(NSData *)message  publicKey:(NSData *)pubkeyData {
+    secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY);
+    secp256k1_ecdsa_signature signature;
+    secp256k1_pubkey pubkey;
+
+    secp256k1_ecdsa_signature_parse_der(ctx, &signature, sigData.bytes, sigData.length);
+    if (secp256k1_ec_pubkey_parse(ctx, &pubkey, pubkeyData.bytes, pubkeyData.length) != 1) {
+        return FALSE;
+    };
+
+    if (secp256k1_ecdsa_verify(ctx, &signature, message.bytes, &pubkey) != 1) {
+        return FALSE;
+    };
+    secp256k1_context_destroy(ctx);
+    return TRUE;
+}
 @end
diff --git a/Sources/BitcoinKit/Core/Crypto.swift b/Sources/BitcoinKit/Core/Crypto.swift
@@ -29,7 +29,6 @@ import BitcoinKit.Private
 #else
 import BitcoinKitPrivate
 #endif
-import secp256k1
 
 public struct Crypto {
     public static func sha1(_ data: Data) -> Data {
@@ -66,26 +65,7 @@ public struct Crypto {
 
     public static func verifySignature(_ signature: Data, message: Data, publicKey: Data) throws -> Bool {
         #if BitcoinKitXcode
-        let ctx = secp256k1_context_create(UInt32(SECP256K1_CONTEXT_VERIFY))!
-        defer { secp256k1_context_destroy(ctx) }
-
-        let signaturePointer = UnsafeMutablePointer<secp256k1_ecdsa_signature>.allocate(capacity: 1)
-        defer { signaturePointer.deallocate() }
-        guard signature.withUnsafeBytes({ secp256k1_ecdsa_signature_parse_der(ctx, signaturePointer, $0, signature.count) }) == 1 else {
-            print("signature : ", signature.hex)
-            throw CryptoError.signatureParseFailed
-        }
-
-        let pubkeyPointer = UnsafeMutablePointer<secp256k1_pubkey>.allocate(capacity: 1)
-        defer { pubkeyPointer.deallocate() }
-        guard publicKey.withUnsafeBytes({ secp256k1_ec_pubkey_parse(ctx, pubkeyPointer, $0, publicKey.count) }) == 1 else {
-            throw CryptoError.publicKeyParseFailed
-        }
-
-        guard message.withUnsafeBytes ({ secp256k1_ecdsa_verify(ctx, signaturePointer, $0, pubkeyPointer) }) == 1 else {
-            return false
-        }
-        return true
+        return _Crypto.verifySignature(signature, message: message, publicKey: publicKey)
         #else
         return try _Crypto.verifySignature(signature, message: message, publicKey: publicKey)
         #endif