xref: /openssh-portable/hmac.h (revision 8668706d)
1 /* $OpenBSD: hmac.h,v 1.9 2014/06/24 01:13:21 djm Exp $ */
2 /*
3  * Copyright (c) 2014 Markus Friedl.  All rights reserved.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #ifndef _HMAC_H
19 #define _HMAC_H
20 
21 /* Returns the algorithm's digest length in bytes or 0 for invalid algorithm */
22 size_t ssh_hmac_bytes(int alg);
23 
24 struct sshbuf;
25 struct ssh_hmac_ctx;
26 struct ssh_hmac_ctx *ssh_hmac_start(int alg);
27 
28 /* Sets the state of the HMAC or resets the state if key == NULL */
29 int ssh_hmac_init(struct ssh_hmac_ctx *ctx, const void *key, size_t klen)
30 	__attribute__((__bounded__(__buffer__, 2, 3)));
31 int ssh_hmac_update(struct ssh_hmac_ctx *ctx, const void *m, size_t mlen)
32 	__attribute__((__bounded__(__buffer__, 2, 3)));
33 int ssh_hmac_update_buffer(struct ssh_hmac_ctx *ctx, const struct sshbuf *b);
34 int ssh_hmac_final(struct ssh_hmac_ctx *ctx, u_char *d, size_t dlen)
35 	__attribute__((__bounded__(__buffer__, 2, 3)));
36 void ssh_hmac_free(struct ssh_hmac_ctx *ctx);
37 
38 #endif /* _HMAC_H */
39