Add support for MLDSA keys (#631)

* WIP.

* WIP

* WIP Edit

* Key selection.

* WIP

* WIP

* Proxy through

* WIP

* Remove verify.

* Migration.

* Comment

* Add param

* Semi-offering key

* Ignore updates if test build.

* Fix rsa public key gen

* Messily fix RSA

* Remove 1024 bit rsa

* Cleanup

* Cleanup

* MLDSA warning.

* MLDSA working.

* Strings.

* Put back UI changes

Sources/Packages/Sources/SecretKit/OpenSSH/OpenSSHPublicKeyWriter.swift

@@ -17,6 +17,10 @@ public struct OpenSSHPublicKeyWriter: Sendable {
             openSSHIdentifier(for: secret.keyType).lengthAndData +
             ("nistp" + String(describing: secret.keyType.size)).lengthAndData +
             secret.publicKey.lengthAndData
+        case .mldsa:
+            // https://www.ietf.org/archive/id/draft-sfluhrer-ssh-mldsa-04.txt
+            openSSHIdentifier(for: secret.keyType).lengthAndData +
+            secret.publicKey.lengthAndData
         case .rsa:
             // https://datatracker.ietf.org/doc/html/rfc4253#section-6.6
             openSSHIdentifier(for: secret.keyType).lengthAndData +
@@ -72,8 +76,14 @@ extension OpenSSHPublicKeyWriter {
     /// - Returns: The OpenSSH identifier for the algorithm.
     public func openSSHIdentifier(for keyType: KeyType) -> String {
         switch (keyType.algorithm, keyType.size) {
-        case (.ecdsa, 256), (.ecdsa, 384):
-            "ecdsa-sha2-nistp" + String(describing: keyType.size)
+        case (.ecdsa, 256):
+            "ecdsa-sha2-nistp256"
+        case (.ecdsa, 384):
+            "ecdsa-sha2-nistp384"
+        case (.mldsa, 65):
+            "ssh-mldsa-65"
+        case (.mldsa, 87):
+            "ssh-mldsa-87"
         case (.rsa, _):
             "ssh-rsa"
         default:

Sources/Packages/Sources/SecretKit/OpenSSH/OpenSSHSignatureWriter.swift

@@ -15,6 +15,9 @@ public struct OpenSSHSignatureWriter: Sendable {
         case .ecdsa:
             // https://datatracker.ietf.org/doc/html/rfc5656#section-3.1
             ecdsaSignature(signature, keyType: secret.keyType)
+        case .mldsa:
+            // https://datatracker.ietf.org/doc/html/draft-sfluhrer-ssh-mldsa-00#name-public-key-algorithms
+            mldsaSignature(signature, keyType: secret.keyType)
         case .rsa:
             // https://datatracker.ietf.org/doc/html/rfc4253#section-6.6
             rsaSignature(signature)
@@ -51,6 +54,15 @@ extension OpenSSHSignatureWriter {
         return mutSignedData
     }
 
+    func mldsaSignature(_ rawRepresentation: Data, keyType: KeyType) -> Data {
+        var mutSignedData = Data()
+        var sub = Data()
+        sub.append(OpenSSHPublicKeyWriter().openSSHIdentifier(for: keyType).lengthAndData)
+        sub.append(rawRepresentation.lengthAndData)
+        mutSignedData.append(sub.lengthAndData)
+        return mutSignedData
+    }
+
     func rsaSignature(_ rawRepresentation: Data) -> Data {
         var mutSignedData = Data()
         var sub = Data()

Sources/Packages/Sources/SecretKit/Types/Secret.swift

@@ -35,6 +35,7 @@ public struct KeyType: Hashable, Sendable, Codable, CustomStringConvertible {
     
     public enum Algorithm: Hashable, Sendable, Codable {
         case ecdsa
+        case mldsa
         case rsa
     }
 
@@ -67,6 +68,8 @@ public struct KeyType: Hashable, Sendable, Codable, CustomStringConvertible {
             kSecAttrKeyTypeEC
         case .rsa:
             kSecAttrKeyTypeRSA
+        case .mldsa:
+            nil
         }
     }
     

Sources/Packages/Sources/SecureEnclaveSecretKit/SecureEnclaveStore.swift

@@ -39,10 +39,10 @@ extension SecureEnclave {
                 context = existing.context
             } else {
                 let newContext = LAContext()
-                newContext.localizedCancelTitle = String(localized: "auth_context_request_deny_button")
+                newContext.localizedReason = String(localized: .authContextRequestSignatureDescription(appName: provenance.origin.displayName, secretName: secret.name))
+                newContext.localizedCancelTitle = String(localized: .authContextRequestDenyButton)
                 context = newContext
             }
-            context.localizedReason = String(localized: "auth_context_request_signature_description_\(provenance.origin.displayName)_\(secret.name)")
 
             let queryAttributes = KeychainDictionary([
                 kSecClass: Constants.keyClass,
@@ -68,8 +68,16 @@ extension SecureEnclave {
 
             switch (attributes.keyType.algorithm, attributes.keyType.size) {
             case (.ecdsa, 256):
-                let key = try CryptoKit.SecureEnclave.P256.Signing.PrivateKey(dataRepresentation: keyData)
+                let key = try CryptoKit.SecureEnclave.P256.Signing.PrivateKey(dataRepresentation: keyData, authenticationContext: context)
                 return try key.signature(for: data).rawRepresentation
+            case (.mldsa, 65):
+                guard #available(macOS 26.0, *)  else { throw UnsupportedAlgorithmError() }
+                let key = try CryptoKit.SecureEnclave.MLDSA65.PrivateKey(dataRepresentation: keyData)
+                return try key.signature(for: data)
+            case (.mldsa, 87):
+                guard #available(macOS 26.0, *)  else { throw UnsupportedAlgorithmError() }
+                let key = try CryptoKit.SecureEnclave.MLDSA87.PrivateKey(dataRepresentation: keyData)
+                return try key.signature(for: data)
             default:
                 throw UnsupportedAlgorithmError()
             }
@@ -115,6 +123,14 @@ extension SecureEnclave {
             case (.ecdsa, 256):
                 let created = try CryptoKit.SecureEnclave.P256.Signing.PrivateKey(accessControl: access!)
                 dataRep = created.dataRepresentation
+            case (.mldsa, 65):
+                guard #available(macOS 26.0, *) else { throw Attributes.UnsupportedOptionError() }
+                let created = try CryptoKit.SecureEnclave.MLDSA65.PrivateKey(accessControl: access!)
+                dataRep = created.dataRepresentation
+            case (.mldsa, 87):
+                guard #available(macOS 26.0, *) else { throw Attributes.UnsupportedOptionError() }
+                let created = try CryptoKit.SecureEnclave.MLDSA87.PrivateKey(accessControl: access!)
+                dataRep = created.dataRepresentation
             default:
                 throw Attributes.UnsupportedOptionError()
             }
@@ -127,7 +143,8 @@ extension SecureEnclave {
                 kSecClass: Constants.keyClass,
                 kSecAttrService: Constants.keyTag,
                 kSecUseDataProtectionKeychain: true,
-                kSecAttrAccount: String(decoding: secret.id, as: UTF8.self)
+                kSecAttrAccount: String(decoding: secret.id, as: UTF8.self),
+                kSecAttrCanSign: true,
             ])
             let status = SecItemDelete(deleteAttributes)
             if status != errSecSuccess {
@@ -156,6 +173,8 @@ extension SecureEnclave {
         public var supportedKeyTypes: [KeyType] {
             [
                 .init(algorithm: .ecdsa, size: 256),
+                .init(algorithm: .mldsa, size: 65),
+                .init(algorithm: .mldsa, size: 87),
             ]
         }
 
@@ -205,6 +224,14 @@ extension SecureEnclave.Store {
                 case (.ecdsa, 256):
                     let key = try CryptoKit.SecureEnclave.P256.Signing.PrivateKey(dataRepresentation: keyData)
                     publicKey = key.publicKey.x963Representation
+                case (.mldsa, 65):
+                    guard #available(macOS 26.0, *)  else { throw UnsupportedAlgorithmError() }
+                    let key = try CryptoKit.SecureEnclave.MLDSA65.PrivateKey(dataRepresentation: keyData)
+                    publicKey = key.publicKey.rawRepresentation
+                case (.mldsa, 87):
+                    guard #available(macOS 26.0, *)  else { throw UnsupportedAlgorithmError() }
+                    let key = try CryptoKit.SecureEnclave.MLDSA87.PrivateKey(dataRepresentation: keyData)
+                    publicKey = key.publicKey.rawRepresentation
                 default:
                     throw UnsupportedAlgorithmError()
                 }