.

Sources/Packages/Sources/SecretAgentKit/Agent.swift

@@ -45,6 +45,8 @@ extension Agent {
                 response.append(SSHAgent.Response.agentSignResponse.data)
                 response.append(try await sign(data: context.dataToSign, keyBlob: context.keyBlob, provenance: provenance))
                 logger.debug("Agent returned \(SSHAgent.Response.agentSignResponse.debugDescription)")
+            case .unknown(let value):
+                logger.error("Agent received unknown request of type \(value).")
             default:
                 logger.debug("Agent received valid request of type \(request.debugDescription), but not currently supported.")
                 throw UnhandledRequestError()

Sources/Packages/Sources/SecretAgentKit/OpenSSHReader.swift

@@ -7,25 +7,25 @@ final class OpenSSHReader {
 
     /// Initialize the reader with an OpenSSH data payload.
     /// - Parameter data: The data to read.
-    public init(data: Data) {
+    init(data: Data) {
         remaining = Data(data)
     }
 
     /// Reads the next chunk of data from the playload.
     /// - Returns: The next chunk of data.
-    public func readNextChunk(convertEndianness: Bool = true) throws -> Data {
+    func readNextChunk(convertEndianness: Bool = true) throws(OpenSSHReaderError) -> Data {
         let littleEndianLength = try readNextBytes(as: UInt32.self)
         let length = convertEndianness ? Int(littleEndianLength.bigEndian) : Int(littleEndianLength)
-        guard remaining.count >= length else { throw EndOfData() }
+        guard remaining.count >= length else { throw .beyondBounds }
         let dataRange = 0..<length
         let ret = Data(remaining[dataRange])
         remaining.removeSubrange(dataRange)
         return ret
     }
 
-    public func readNextBytes<T>(as: T.Type) throws -> T {
+    func readNextBytes<T>(as: T.Type) throws(OpenSSHReaderError) -> T {
         let size = MemoryLayout<T>.size
-        guard remaining.count >= size else { throw EndOfData() }
+        guard remaining.count >= size else { throw .beyondBounds }
         let lengthRange = 0..<size
         let lengthChunk = remaining[lengthRange]
         remaining.removeSubrange(lengthRange)
@@ -33,10 +33,12 @@ final class OpenSSHReader {
     }
 
 
-    public func readNextChunkAsString() throws -> String {
+    func readNextChunkAsString() throws -> String {
         try String(decoding: readNextChunk(), as: UTF8.self)
     }
 
-    public struct EndOfData: Error {}
-
+}
+
+public enum OpenSSHReaderError: Error, Codable {
+    case beyondBounds
 }

Sources/Packages/Sources/SecretAgentKit/SSHAgentInputParser.swift

@@ -16,10 +16,10 @@ public struct SSHAgentInputParser: SSHAgentInputParserProtocol {
         
     }
 
-    public func parse(data: Data) throws -> SSHAgent.Request {
+    public func parse(data: Data) throws(AgentParsingError) -> SSHAgent.Request {
         logger.debug("Parsing new data")
         guard data.count > 4 else {
-            throw InvalidDataProvidedError()
+            throw .invalidData
         }
         let specifiedLength = (data[0..<4].bytes.unsafeLoad(as: UInt32.self).bigEndian) + 4
         let rawRequestInt = data[4]
@@ -29,7 +29,11 @@ public struct SSHAgentInputParser: SSHAgentInputParserProtocol {
         case SSHAgent.Request.requestIdentities.protocolID:
             return .requestIdentities
         case SSHAgent.Request.signRequest(.empty).protocolID:
-            return .signRequest(try signatureRequestContext(from: body))
+            do {
+                return .signRequest(try signatureRequestContext(from: body))
+            } catch {
+                throw .openSSHReader(error)
+            }
         case SSHAgent.Request.addIdentity.protocolID:
             return .addIdentity
         case SSHAgent.Request.removeIdentity.protocolID:
@@ -59,7 +63,7 @@ public struct SSHAgentInputParser: SSHAgentInputParserProtocol {
 
 extension SSHAgentInputParser {
 
-    func signatureRequestContext(from data: Data) throws -> SSHAgent.Request.SignatureRequestContext {
+    func signatureRequestContext(from data: Data) throws(OpenSSHReaderError) -> SSHAgent.Request.SignatureRequestContext {
         let reader = OpenSSHReader(data: data)
         let rawKeyBlob = try reader.readNextChunk()
         let keyBlob = certificatePublicKeyBlob(from: rawKeyBlob) ?? rawKeyBlob
@@ -95,8 +99,11 @@ extension SSHAgentInputParser {
 
 extension SSHAgentInputParser {
 
-    struct AgentUnknownRequestError: Error {}
-    struct AgentUnhandledRequestError: Error {}
-    struct InvalidDataProvidedError: Error {}
+    public enum AgentParsingError: Error, Codable {
+        case unknownRequest
+        case unhandledRequest
+        case invalidData
+        case openSSHReader(OpenSSHReaderError)
+    }
 
 }