Add HMAC implementation to HashProvider

git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@12508 e03df62e-2008-0410-955e-edbf42e46eb7

1 files changed, 70 insertions, 0 deletions

diff --git a/src/modules/hash.h b/src/modules/hash.h
new file mode 100644
index 000000000..7e93f0ddc
--- /dev/null
+++ b/src/modules/hash.h
@@ -0,0 +1,70 @@
+/*       +------------------------------------+
+ *       | Inspire Internet Relay Chat Daemon |
+ *       +------------------------------------+
+ *
+ *  InspIRCd: (C) 2002-2010 InspIRCd Development Team
+ * See: http://wiki.inspircd.org/Credits
+ *
+ * This program is free but copyrighted software; see
+ *            the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
+
+#ifndef __HASH_H__
+#define __HASH_H__
+
+#include "modules.h"
+
+class HashProvider : public DataProvider
+{
+ public:
+	const unsigned int out_size;
+	const unsigned int block_size;
+	HashProvider(Module* mod, const std::string& Name, int osiz, int bsiz)
+		: DataProvider(mod, Name), out_size(osiz), block_size(bsiz) {}
+	virtual std::string sum(const std::string& data) = 0;
+	inline std::string hexsum(const std::string& data)
+	{
+		return BinToHex(sum(data));
+	}
+
+	inline std::string b64sum(const std::string& data)
+	{
+		return BinToBase64(sum(data), NULL, 0);
+	}
+
+	/** Allows the IVs for the hash to be specified. As the choice of initial IV is
+	 * important for the security of a hash, this should not be used except to
+	 * maintain backwards compatability. This also allows you to change the hex
+	 * sequence from its default of "0123456789abcdef", which does not improve the
+	 * strength of the output, but helps confuse those attempting to implement it.
+	 *
+	 * Example:
+	 * \code
+	 * unsigned int iv[] = { 0xFFFFFFFF, 0x00000000, 0xAAAAAAAA, 0xCCCCCCCC };
+	 * std::string result = Hash.sumIV(iv, "fedcba9876543210", "data");
+	 * \endcode
+	 */
+	virtual std::string sumIV(unsigned int* IV, const char* HexMap, const std::string &sdata) = 0;
+
+	/** HMAC algorithm, RFC 2104 */
+	std::string hmac(const std::string& key, const std::string& msg)
+	{
+		std::string hmac1, hmac2;
+		std::string kbuf = key.length() > block_size ? sum(key) : key;
+		kbuf.resize(block_size);
+
+		for (size_t n = 0; n < block_size; n++)
+		{
+			hmac1.push_back(static_cast<char>(kbuf[n] ^ 0x5C));
+			hmac2.push_back(static_cast<char>(kbuf[n] ^ 0x36));
+		}
+		hmac2.append(msg);
+		hmac1.append(sum(hmac2));
+		return sum(hmac1);
+	}
+};
+
+#endif
+