Add SHA1 and SHA1-HMAC crypto hash

1 files changed, 86 insertions, 0 deletions

diff --git a/lib/sha1.h b/lib/sha1.h
new file mode 100644
index 00000000..425160a0
--- /dev/null
+++ b/lib/sha1.h
@@ -0,0 +1,86 @@
+/*
+ *	BIRD Library -- SHA-1 Hash Function (FIPS 180-1, RFC 3174) and HMAC-SHA-1
+ *
+ *	(c) 2015 CZ.NIC z.s.p.o.
+ *
+ *	Based on the code from libucw-6.4
+ *	(c) 2008--2009 Martin Mares <mj@ucw.cz>
+ *
+ *	Based on the code from libgcrypt-1.2.3, which is
+ *	(c) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_SHA1_H_
+#define _BIRD_SHA1_H_
+
+#include "nest/bird.h"
+
+/*
+ * Internal SHA1 state.
+ * You should use it just as an opaque handle only.
+ */
+struct sha1_context {
+  u32 h0,h1,h2,h3,h4;
+  u32 nblocks;
+  byte buf[64];
+  int count;
+} ;
+
+void sha1_init(struct sha1_context *hd); /* Initialize new algorithm run in the @hd context. **/
+/*
+ * Push another @inlen bytes of data pointed to by @inbuf onto the
+ * SHA1 hash currently in @hd. You can call this any times you want on
+ * the same hash (and you do not need to reinitialize it by
+ * @sha1_init()). It has the same effect as concatenating all the data
+ * together and passing them at once.
+ */
+void sha1_update(struct sha1_context *hd, const byte *inbuf, uint inlen);
+/*
+ * No more @sha1_update() calls will be done. This terminates the hash
+ * and returns a pointer to it.
+ *
+ * Note that the pointer points into data in the @hd context. If it ceases
+ * to exist, the pointer becomes invalid.
+ *
+ * To convert the hash to its usual hexadecimal representation, see
+ * <<string:mem_to_hex()>>.
+ */
+byte *sha1_final(struct sha1_context *hd);
+
+/*
+ * A convenience one-shot function for SHA1 hash.
+ * It is equivalent to this snippet of code:
+ *
+ *  sha1_context hd;
+ *  sha1_init(&hd);
+ *  sha1_update(&hd, buffer, length);
+ *  memcpy(outbuf, sha1_final(&hd), SHA1_SIZE);
+ */
+void sha1_hash_buffer(byte *outbuf, const byte *buffer, uint length);
+
+/*
+ * SHA1 HMAC message authentication. If you provide @key and @data,
+ * the result will be stored in @outbuf.
+ */
+void sha1_hmac(byte *outbuf, const byte *key, uint keylen, const byte *data, uint datalen);
+
+/*
+ * The HMAC also exists in a stream version in a way analogous to the
+ * plain SHA1. Pass this as a context.
+ */
+struct sha1_hmac_context {
+  struct sha1_context ictx;
+  struct sha1_context octx;
+};
+
+void sha1_hmac_init(struct sha1_hmac_context *hd, const byte *key, uint keylen);	/* Initialize HMAC with context @hd and the given key. See sha1_init(). */
+void sha1_hmac_update(struct sha1_hmac_context *hd, const byte *data, uint datalen);	/* Hash another @datalen bytes of data. See sha1_update(). */
+byte *sha1_hmac_final(struct sha1_hmac_context *hd);					/* Terminate the HMAC and return a pointer to the allocated hash. See sha1_final(). */
+
+#define SHA1_SIZE 20 		/* Size of the SHA1 hash in its binary representation **/
+#define SHA1_HEX_SIZE 41 	/* Buffer length for a string containing SHA1 in hexadecimal format. **/
+#define SHA1_BLOCK_SIZE 64 	/* SHA1 splits input to blocks of this size. **/
+
+#endif /* _BIRD_SHA1_H_ */