1 files changed, 66 insertions, 0 deletions
diff --git a/Swiften/StringCodecs/HMAC.h b/Swiften/StringCodecs/HMAC.h
new file mode 100644
index 0000000..cf0abfe
--- /dev/null
+++ b/Swiften/StringCodecs/HMAC.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2010 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#pragma once
+
+#include <Swiften/Base/ByteArray.h>
+#include <Swiften/Base/Algorithm.h>
+#include <cassert>
+
+namespace Swift {
+	namespace HMAC_Detail {
+		template<typename KeyType> struct KeyWrapper;
+		template<> struct KeyWrapper<ByteArray> {
+			ByteArray wrap(const ByteArray& hash) const {
+				return hash;
+			}
+		};
+		template<> struct KeyWrapper<SafeByteArray> {
+			SafeByteArray wrap(const ByteArray& hash) const {
+				return createSafeByteArray(hash);
+			}
+		};
+
+		template<typename Hash, typename KeyType, int BlockSize>
+		static ByteArray getHMAC(const KeyType& key, const ByteArray& data) {
+			Hash hash;
+
+			// Create the padded key
+			KeyType paddedKey(key.size() <= BlockSize ? key : KeyWrapper<KeyType>().wrap(hash(key)));
+			paddedKey.resize(BlockSize, 0x0);
+
+			// Create the first value
+			KeyType x(paddedKey);
+			for (unsigned int i = 0; i < x.size(); ++i) {
+				x[i] ^= 0x36;
+			}
+			append(x, data);
+
+			// Create the second value
+			KeyType y(paddedKey);
+			for (unsigned int i = 0; i < y.size(); ++i) {
+				y[i] ^= 0x5c;
+			}
+			append(y, hash(x));
+
+			return hash(y);
+		}
+	};
+
+	template<typename Hash, int BlockSize>
+	class HMAC {
+		private:
+
+		public:
+			ByteArray operator()(const ByteArray& key, const ByteArray& data) const {
+				return HMAC_Detail::getHMAC<Hash,ByteArray,BlockSize>(key, data);
+			}
+
+			ByteArray operator()(const SafeByteArray& key, const ByteArray& data) const {
+				return HMAC_Detail::getHMAC<Hash,SafeByteArray,BlockSize>(key, data);
+			}
+	};
+}