From cd65e1094fb0a9a6119aa7d7fa99baf929405470 Mon Sep 17 00:00:00 2001
From: Si Beaumont <beaumont@apple.com>
Date: Thu, 6 Jun 2024 12:19:36 +0100
Subject: [PATCH] extras: Add meaningful description to BoringSSL errors

---
 .../Util/CryptoKitErrors_boring.swift         | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/Sources/_CryptoExtras/Util/CryptoKitErrors_boring.swift b/Sources/_CryptoExtras/Util/CryptoKitErrors_boring.swift
index 55b3cb37..fde5d02e 100644
--- a/Sources/_CryptoExtras/Util/CryptoKitErrors_boring.swift
+++ b/Sources/_CryptoExtras/Util/CryptoKitErrors_boring.swift
@@ -22,3 +22,28 @@ extension CryptoKitError {
         return .underlyingCoreCryptoError(error: Int32(bitPattern: CCryptoBoringSSL_ERR_get_error()))
     }
 }
+
+extension CryptoKitError {
+    public var description: String {
+        switch self {
+        case .underlyingCoreCryptoError(error: let error):
+            let errorCode = UInt32(bitPattern: error)
+            let lib = String(cString: CCryptoBoringSSL_ERR_lib_error_string(errorCode))
+            let reason = String(cString: CCryptoBoringSSL_ERR_reason_error_string(errorCode))
+            return "lib: \(lib), reason: \(reason), code: \(errorCode)"
+        case .incorrectKeySize: return "incorrectKeySize"
+        case .incorrectParameterSize: return "incorrectParameterSize"
+        case .authenticationFailure: return "authenticationFailure"
+        case .wrapFailure: return "wrapFailure"
+        case .unwrapFailure: return "unwrapFailure"
+        case .invalidParameter: return "invalidParameter"
+        @unknown default: return "unknown"
+        }
+    }
+}
+
+#if hasAttribute(retroactive)
+extension CryptoKitError: @retroactive CustomStringConvertible {}
+#else
+extension CryptoKitError: CustomStringConvertible {}
+#endif