Better error handling in SubtleCrypto workers (#71693)

* Better error handling in SubtleCrypto workers

Handle exceptions from SubtleCrypto by catching and logging exceptions coming from the crypto stack.

Reset web worker when a request fails.

Also, fix race conditions where the web worker can read its own response as part of the next request.

Contributes to #69740

src/libraries/System.Security.Cryptography/src/Resources/Strings.resx

@@ -753,6 +753,9 @@
   <data name="Unknown_Error" xml:space="preserve">
     <value>Unknown error.</value>
   </data>
+  <data name="Unknown_SubtleCrypto_Error" xml:space="preserve">
+    <value>SubtleCrypto returned an unknown error: '{0}'.</value>
+  </data>
   <data name="PlatformNotSupported_CipherModeBrowser" xml:space="preserve">
     <value>Only CipherMode.CBC is supported on this platform.</value>
   </data>

src/libraries/System.Security.Cryptography/src/System/Security/Cryptography/AesSubtleCryptoTransform.Browser.cs

@@ -148,7 +148,7 @@ private unsafe int EncryptDecrypt(ReadOnlySpan<byte> input, Span<byte> output)
                     pOutput, output.Length);
 
                 if (bytesWritten < 0)
-                    throw new Exception(SR.Unknown_Error);
+                    throw new CryptographicException(SR.Format(SR.Unknown_SubtleCrypto_Error, bytesWritten));
 
                 return bytesWritten;
             }

src/libraries/System.Security.Cryptography/src/System/Security/Cryptography/HMACHashProvider.Browser.Native.cs

@@ -43,42 +43,35 @@ public override int GetCurrentHash(Span<byte> destination)
         {
             Debug.Assert(destination.Length >= _hashSizeInBytes);
 
-            byte[] srcArray = Array.Empty<byte>();
-            int srcLength = 0;
-            if (_buffer != null)
-            {
-                srcArray = _buffer.GetBuffer();
-                srcLength = (int)_buffer.Length;
-            }
+            ReadOnlySpan<byte> source = _buffer != null ?
+                new ReadOnlySpan<byte>(_buffer.GetBuffer(), 0, (int)_buffer.Length) :
+                default;
 
-            unsafe
-            {
-                fixed (byte* key = _key)
-                fixed (byte* src = srcArray)
-                fixed (byte* dest = destination)
-                {
-                    int res = Interop.BrowserCrypto.Sign(_hashAlgorithm, key, _key.Length, src, srcLength, dest, destination.Length);
-                    Debug.Assert(res != 0);
-                }
-            }
+            Sign(_hashAlgorithm, _key, source, destination);
 
             return _hashSizeInBytes;
         }
 
-        public static unsafe int MacDataOneShot(string hashAlgorithmId, ReadOnlySpan<byte> key, ReadOnlySpan<byte> data, Span<byte> destination)
+        public static int MacDataOneShot(string hashAlgorithmId, ReadOnlySpan<byte> key, ReadOnlySpan<byte> data, Span<byte> destination)
         {
             (SimpleDigest hashName, int hashSizeInBytes) = SHANativeHashProvider.HashAlgorithmToPal(hashAlgorithmId);
             Debug.Assert(destination.Length >= hashSizeInBytes);
 
+            Sign(hashName, key, data, destination);
+
+            return hashSizeInBytes;
+        }
+
+        private static unsafe void Sign(SimpleDigest hashName, ReadOnlySpan<byte> key, ReadOnlySpan<byte> data, Span<byte> destination)
+        {
             fixed (byte* k = key)
             fixed (byte* src = data)
             fixed (byte* dest = destination)
             {
                 int res = Interop.BrowserCrypto.Sign(hashName, k, key.Length, src, data.Length, dest, destination.Length);
-                Debug.Assert(res != 0);
+                if (res != 0)
+                    throw new CryptographicException(SR.Format(SR.Unknown_SubtleCrypto_Error, res));
             }
-
-            return hashSizeInBytes;
         }
 
         public override int HashSizeInBytes => _hashSizeInBytes;

src/libraries/System.Security.Cryptography/src/System/Security/Cryptography/SHAHashProvider.Browser.Native.cs

@@ -40,40 +40,34 @@ public override int GetCurrentHash(Span<byte> destination)
         {
             Debug.Assert(destination.Length >= _hashSizeInBytes);
 
-            byte[] srcArray = Array.Empty<byte>();
-            int srcLength = 0;
-            if (_buffer != null)
-            {
-                srcArray = _buffer.GetBuffer();
-                srcLength = (int)_buffer.Length;
-            }
+            ReadOnlySpan<byte> source = _buffer != null ?
+                new ReadOnlySpan<byte>(_buffer.GetBuffer(), 0, (int)_buffer.Length) :
+                default;
 
-            unsafe
-            {
-                fixed (byte* src = srcArray)
-                fixed (byte* dest = destination)
-                {
-                    int res = Interop.BrowserCrypto.SimpleDigestHash(_impl, src, srcLength, dest, destination.Length);
-                    Debug.Assert(res != 0);
-                }
-            }
+            SimpleDigestHash(_impl, source, destination);
 
             return _hashSizeInBytes;
         }
 
-        public static unsafe int HashOneShot(string hashAlgorithmId, ReadOnlySpan<byte> data, Span<byte> destination)
+        public static int HashOneShot(string hashAlgorithmId, ReadOnlySpan<byte> data, Span<byte> destination)
         {
             (SimpleDigest impl, int hashSizeInBytes) = HashAlgorithmToPal(hashAlgorithmId);
             Debug.Assert(destination.Length >= hashSizeInBytes);
 
+            SimpleDigestHash(impl, data, destination);
+
+            return hashSizeInBytes;
+        }
+
+        private static unsafe void SimpleDigestHash(SimpleDigest hashName, ReadOnlySpan<byte> data, Span<byte> destination)
+        {
             fixed (byte* src = data)
             fixed (byte* dest = destination)
             {
-                int res = Interop.BrowserCrypto.SimpleDigestHash(impl, src, data.Length, dest, destination.Length);
-                Debug.Assert(res != 0);
+                int res = Interop.BrowserCrypto.SimpleDigestHash(hashName, src, data.Length, dest, destination.Length);
+                if (res != 0)
+                    throw new CryptographicException(SR.Format(SR.Unknown_SubtleCrypto_Error, res));
             }
-
-            return hashSizeInBytes;
         }
 
         public override int HashSizeInBytes => _hashSizeInBytes;