Signature Updates (#338)

21-DOT-DEV · Apr 20, 2023 · d7ff2d3 · d7ff2d3
1 parent 8d033e8
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diff --git a/README.md b/README.md
@@ -20,7 +20,7 @@ Long-term goals are:
 This repository primarily uses Swift package manager as its build tool, so we recommend using that as well. Xcode comes with [built-in support](https://developer.apple.com/documentation/xcode/adding-package-dependencies-to-your-app) for Swift packages. From the menu bar, goto: `File > Add Packages...` If you manage packages via a `Package.swift` file, simply add `secp256k1.swift` as a dependencies' clause in your Swift manifest:
 
 ```swift
-.package(url: "https://github.com/GigaBitcoin/secp256k1.swift.git", .upToNextMajor(from: "0.10.0"))
+.package(url: "https://github.com/GigaBitcoin/secp256k1.swift.git", from: "0.11.0"),
 ```
 
 Try in a [playground](spi-playgrounds://open?dependencies=GigaBitcoin/secp256k1.swift) using the [SPI Playgrounds app](https://swiftpackageindex.com/try-in-a-playground) or 🏟 [Arena](https://github.com/finestructure/arena)
@@ -46,7 +46,7 @@ print(String(bytes: privateKey.publicKey.rawRepresentation))
 
 // ECDSA
 let messageData = "We're all Satoshi.".data(using: .utf8)!
-let signature = try! privateKey.ecdsa.signature(for: messageData)
+let signature = try! privateKey.signature(for: messageData)
 
 //  DER signature
 print(try! signature.derRepresentation.base64EncodedString())
@@ -55,14 +55,14 @@ print(try! signature.derRepresentation.base64EncodedString())
 ## Schnorr
 
 ```swift
-let privateKey = try! secp256k1.Signing.PrivateKey()
+let privateKey = try! secp256k1.Schnorr.PrivateKey()
 
 // Extra params for custom signing
 var auxRand = try! "C87AA53824B4D7AE2EB035A2B5BBBCCC080E76CDC6D1692C4B0B62D798E6D906".bytes
 var messageDigest = try! "7E2D58D8B3BCDF1ABADEC7829054F90DDA9805AAB56C77333024B9D0A508B75C".bytes
 
 // API allows for signing variable length messages
-let signature = try! privateKey.schnorr.signature(message: &messageDigest, auxiliaryRand: &auxRand)
+let signature = try! privateKey.signature(message: &messageDigest, auxiliaryRand: &auxRand)
 ```
 
 ## Tweak
@@ -111,11 +111,11 @@ let privateTweak1 = try! sharedSecretSign1.add(xonly: privateSign1.publicKey.xon
 ## Recovery
 
 ```swift
-let privateKey = try! secp256k1.Signing.PrivateKey()
+let privateKey = try! secp256k1.Recovery.PrivateKey()
 let messageData = "We're all Satoshi.".data(using: .utf8)!
 
 // Create a recoverable ECDSA signature
-let recoverySignature = try! privateKey.ecdsa.recoverableSignature(for: messageData)
+let recoverySignature = try! privateKey.signature(for: messageData)
 
 // Recover an ECDSA public key from a signature
 let publicKey = try! secp256k1.Recovery.PublicKey(messageData, signature: recoverySignature)
@@ -126,5 +126,5 @@ let signature = try! recoverySignature.normalize
 
 
 # Danger
-These APIs should not be considered stable and may change at any time, libsecp256k1 is still experimental and has not been formally released.
+These APIs should not be considered stable and may change at any time.
 
diff --git a/Sources/zkp/Asymmetric.swift b/Sources/zkp/Asymmetric.swift
@@ -25,21 +25,6 @@ public extension secp256k1 {
                 baseKey.key
             }
 
-            /// The ECDSA signing object.
-            ///
-            /// You can use this object to create a digital signature for a given piece of data.
-            public var ecdsa: secp256k1.Signing.ECDSASigner {
-                ECDSASigner(signingKey: baseKey)
-            }
-
-            /// The Schnorr signing object.
-            ///
-            /// You can use this object to create a digital signature for a given piece of data
-            /// using the Schnorr algorithm.
-            public var schnorr: secp256k1.Signing.SchnorrSigner {
-                SchnorrSigner(signingKey: baseKey)
-            }
-
             /// The associated public key for verifying signatures created with this private key.
             ///
             /// - Returns: The associated public key.
@@ -95,21 +80,6 @@ public extension secp256k1 {
                 baseKey.rawRepresentation
             }
 
-            /// The ECDSA validating object.
-            ///
-            /// You can use this object to verify digital signatures created by the corresponding private key.
-            public var ecdsa: secp256k1.Signing.ECDSAValidator {
-                ECDSAValidator(validatingKey: baseKey)
-            }
-
-            /// The Schnorr validating object.
-            ///
-            /// You can use this object to verify digital signatures created by the corresponding private key
-            /// using the Schnorr algorithm.
-            public var schnorr: secp256k1.Signing.SchnorrValidator {
-                SchnorrValidator(validatingKey: baseKey)
-            }
-
             /// The associated x-only public key for verifying Schnorr signatures.
             ///
             /// - Returns: The associated x-only public key.

diff --git a/Sources/zkp/ECDSA.swift b/Sources/zkp/ECDSA.swift
@@ -137,36 +137,7 @@ public extension secp256k1.Signing {
 
 // MARK: - secp256k1 + Signing Key
 
-public extension secp256k1.Signing {
-    struct ECDSASigner {
-        /// Generated secp256k1 Signing Key.
-        var signingKey: PrivateKeyImplementation
-    }
-}
-
-extension secp256k1.Signing.ECDSASigner: DigestSigner, Signer {
-    ///  Generates a recoverable ECDSA signature.
-    ///
-    /// - Parameter digest: The digest to sign.
-    /// - Returns: The recoverable ECDSA Signature.
-    /// - Throws: If there is a failure producing the signature
-    public func recoverableSignature<D: Digest>(for digest: D) throws -> secp256k1.Recovery.ECDSASignature {
-        var signature = secp256k1_ecdsa_recoverable_signature()
-
-        guard secp256k1_ecdsa_sign_recoverable(
-            secp256k1.Context.raw,
-            &signature,
-            Array(digest),
-            Array(signingKey.rawRepresentation),
-            nil,
-            nil
-        ).boolValue else {
-            throw secp256k1Error.underlyingCryptoError
-        }
-
-        return try secp256k1.Recovery.ECDSASignature(signature.dataValue)
-    }
-
+extension secp256k1.Signing.PrivateKey: DigestSigner {
     ///  Generates an ECDSA signature over the secp256k1 elliptic curve.
     ///
     /// - Parameter digest: The digest to sign.
@@ -179,7 +150,7 @@ extension secp256k1.Signing.ECDSASigner: DigestSigner, Signer {
             secp256k1.Context.raw,
             &signature,
             Array(digest),
-            Array(signingKey.rawRepresentation),
+            Array(rawRepresentation),
             nil,
             nil
         ).boolValue else {
@@ -188,17 +159,9 @@ extension secp256k1.Signing.ECDSASigner: DigestSigner, Signer {
 
         return try secp256k1.Signing.ECDSASignature(signature.dataValue)
     }
+}
 
-    /// Generates an ECDSA signature over the secp256k1 elliptic curve.
-    /// SHA256 is used as the hash function.
-    ///
-    /// - Parameter data: The data to sign.
-    /// - Returns: The ECDSA Signature.
-    /// - Throws: If there is a failure producing the signature.
-    public func recoverableSignature<D: DataProtocol>(for data: D) throws -> secp256k1.Recovery.ECDSASignature {
-        try recoverableSignature(for: SHA256.hash(data: data))
-    }
-
+extension secp256k1.Signing.PrivateKey: Signer {
     /// Generates an ECDSA signature over the secp256k1 elliptic curve.
     /// SHA256 is used as the hash function.
     ///
@@ -212,30 +175,25 @@ extension secp256k1.Signing.ECDSASigner: DigestSigner, Signer {
 
 // MARK: - secp256k1 + Validating Key
 
-public extension secp256k1.Signing {
-    struct ECDSAValidator {
-        /// Generated secp256k1 Validating Key.
-        var validatingKey: PublicKeyImplementation
-    }
-}
-
-extension secp256k1.Signing.ECDSAValidator: DigestValidator, DataValidator {
+extension secp256k1.Signing.PublicKey: DigestValidator {
     /// Verifies an ECDSA signature over the secp256k1 elliptic curve.
     ///
     /// - Parameters:
     ///   - signature: The signature to verify
     ///   - digest: The digest that was signed.
     /// - Returns: True if the signature is valid, false otherwise.
     public func isValidSignature<D: Digest>(_ signature: secp256k1.Signing.ECDSASignature, for digest: D) -> Bool {
-        var secp256k1Signature = secp256k1_ecdsa_signature()
-        var secp256k1PublicKey = secp256k1_pubkey()
+        var ecdsaSignature = secp256k1_ecdsa_signature()
+        var publicKey = secp256k1_pubkey()
 
-        signature.rawRepresentation.copyToUnsafeMutableBytes(of: &secp256k1Signature.data)
+        signature.rawRepresentation.copyToUnsafeMutableBytes(of: &ecdsaSignature.data)
 
-        return secp256k1_ec_pubkey_parse(secp256k1.Context.raw, &secp256k1PublicKey, validatingKey.bytes, validatingKey.bytes.count).boolValue &&
-            secp256k1_ecdsa_verify(secp256k1.Context.raw, &secp256k1Signature, Array(digest), &secp256k1PublicKey).boolValue
+        return secp256k1_ec_pubkey_parse(secp256k1.Context.raw, &publicKey, bytes, bytes.count).boolValue &&
+            secp256k1_ecdsa_verify(secp256k1.Context.raw, &ecdsaSignature, Array(digest), &publicKey).boolValue
     }
+}
 
+extension secp256k1.Signing.PublicKey: DataValidator {
     /// Verifies an ECDSA signature over the secp256k1 elliptic curve.
     /// SHA256 is used as the hash function.
     ///