diff options
Diffstat (limited to 'lib/sha1.h')
-rw-r--r-- | lib/sha1.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/lib/sha1.h b/lib/sha1.h new file mode 100644 index 00000000..c019bb49 --- /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" + + +#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. */ + + +/* + * Internal SHA1 state. + * You should use it just as an opaque handle only. + */ +struct sha1_context { + u32 h0, h1, h2, h3, h4; + byte buf[SHA1_BLOCK_SIZE]; + uint nblocks; + uint count; +}; + + +void sha1_init(struct sha1_context *ctx); /* Initialize new algorithm run in the @ctx context. **/ +/* + * Push another @len bytes of data pointed to by @buf onto the SHA1 hash + * currently in @ctx. 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 *ctx, const byte *buf, uint len); +/* + * 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 @ctx context. If it ceases to + * exist, the pointer becomes invalid. + */ +byte *sha1_final(struct sha1_context *ctx); + +/* + * A convenience one-shot function for SHA1 hash. It is equivalent to this + * snippet of code: + * + * sha1_context ctx; + * sha1_init(&ctx); + * sha1_update(&ctx, buffer, length); + * memcpy(outbuf, sha1_final(&ctx), 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 *ctx, const byte *key, uint keylen); /* Initialize HMAC with context @ctx and the given key. See sha1_init(). */ +void sha1_hmac_update(struct sha1_hmac_context *ctx, const byte *data, uint datalen); /* Hash another @datalen bytes of data. See sha1_update(). */ +byte *sha1_hmac_final(struct sha1_hmac_context *ctx); /* Terminate the HMAC and return a pointer to the allocated hash. See sha1_final(). */ + + +#endif /* _BIRD_SHA1_H_ */ |