1 files changed, 111 insertions, 0 deletions
diff --git a/src/Native/Unix/System.Security.Cryptography.Native.Apple/pal_hmac.cpp b/src/Native/Unix/System.Security.Cryptography.Native.Apple/pal_hmac.cpp
new file mode 100644
index 0000000000..83fc5717ef
--- /dev/null
+++ b/src/Native/Unix/System.Security.Cryptography.Native.Apple/pal_hmac.cpp
@@ -0,0 +1,111 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#include "pal_hmac.h"
+
+struct hmac_ctx_st
+{
+    CCHmacAlgorithm appleAlgId;
+    CCHmacContext hmac;
+};
+
+extern "C" void AppleCryptoNative_HmacFree(HmacCtx* pHmac)
+{
+    if (pHmac != nullptr)
+    {
+        free(pHmac);
+    }
+}
+
+static CCHmacAlgorithm PalAlgorithmToAppleAlgorithm(PAL_HashAlgorithm algorithm)
+{
+    switch (algorithm)
+    {
+        case PAL_MD5:
+            return kCCHmacAlgMD5;
+        case PAL_SHA1:
+            return kCCHmacAlgSHA1;
+        case PAL_SHA256:
+            return kCCHmacAlgSHA256;
+        case PAL_SHA384:
+            return kCCHmacAlgSHA384;
+        case PAL_SHA512:
+            return kCCHmacAlgSHA512;
+        default:
+            // 0 is a defined value (SHA1) so "unknown" has to be something else
+            return UINT_MAX;
+    }
+}
+
+static int GetHmacOutputSize(PAL_HashAlgorithm algorithm)
+{
+    switch (algorithm)
+    {
+        case PAL_MD5:
+            return CC_MD5_DIGEST_LENGTH;
+        case PAL_SHA1:
+            return CC_SHA1_DIGEST_LENGTH;
+        case PAL_SHA256:
+            return CC_SHA256_DIGEST_LENGTH;
+        case PAL_SHA384:
+            return CC_SHA384_DIGEST_LENGTH;
+        case PAL_SHA512:
+            return CC_SHA512_DIGEST_LENGTH;
+        default:
+            return -1;
+    }
+}
+
+extern "C" HmacCtx* AppleCryptoNative_HmacCreate(PAL_HashAlgorithm algorithm, int32_t* pcbHmac)
+{
+    if (pcbHmac == nullptr)
+        return nullptr;
+
+    CCHmacAlgorithm appleAlgId = PalAlgorithmToAppleAlgorithm(algorithm);
+
+    if (appleAlgId == UINT_MAX)
+    {
+        *pcbHmac = -1;
+        return nullptr;
+    }
+
+    HmacCtx* hmacCtx = reinterpret_cast<HmacCtx*>(malloc(sizeof(HmacCtx)));
+    hmacCtx->appleAlgId = appleAlgId;
+    *pcbHmac = GetHmacOutputSize(algorithm);
+    return hmacCtx;
+}
+
+extern "C" int AppleCryptoNative_HmacInit(HmacCtx* ctx, uint8_t* pbKey, int32_t cbKey)
+{
+    if (ctx == nullptr || cbKey < 0)
+        return 0;
+    if (cbKey != 0 && pbKey == nullptr)
+        return 0;
+
+    // No return value
+    CCHmacInit(&ctx->hmac, ctx->appleAlgId, pbKey, static_cast<size_t>(cbKey));
+    return 1;
+}
+
+extern "C" int AppleCryptoNative_HmacUpdate(HmacCtx* ctx, uint8_t* pbData, int32_t cbData)
+{
+    if (cbData == 0)
+        return 1;
+    if (ctx == nullptr || pbData == nullptr)
+        return 0;
+
+    // No return value
+    CCHmacUpdate(&ctx->hmac, pbData, static_cast<size_t>(cbData));
+    return 1;
+}
+
+extern "C" int AppleCryptoNative_HmacFinal(HmacCtx* ctx, uint8_t* pbOutput)
+{
+    if (ctx == nullptr || pbOutput == nullptr)
+        return 0;
+
+    // No return value
+    CCHmacFinal(&ctx->hmac, pbOutput);
+    return 1;
+}