1/* $OpenBSD: digest.h,v 1.8 2017/05/08 22:57:38 djm Exp $ */
2/*
3 * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
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 _DIGEST_H
19#define _DIGEST_H
20
21/* Maximum digest output length */
22#define SSH_DIGEST_MAX_LENGTH	64
23
24/* Digest algorithms */
25#define SSH_DIGEST_MD5		0
26#define SSH_DIGEST_SHA1		1
27#define SSH_DIGEST_SHA256	2
28#define SSH_DIGEST_SHA384	3
29#define SSH_DIGEST_SHA512	4
30#define SSH_DIGEST_MAX		5
31
32struct sshbuf;
33struct ssh_digest_ctx;
34
35/* Looks up a digest algorithm by name */
36int ssh_digest_alg_by_name(const char *name);
37
38/* Returns the algorithm name for a digest identifier */
39const char *ssh_digest_alg_name(int alg);
40
41/* Returns the algorithm's digest length in bytes or 0 for invalid algorithm */
42size_t ssh_digest_bytes(int alg);
43
44/* Returns the block size of the digest, e.g. for implementing HMAC */
45size_t ssh_digest_blocksize(struct ssh_digest_ctx *ctx);
46
47/* Copies internal state of digest of 'from' to 'to' */
48int ssh_digest_copy_state(struct ssh_digest_ctx *from,
49    struct ssh_digest_ctx *to);
50
51/* One-shot API */
52int ssh_digest_memory(int alg, const void *m, size_t mlen,
53    u_char *d, size_t dlen)
54	__attribute__((__bounded__(__buffer__, 2, 3)))
55	__attribute__((__bounded__(__buffer__, 4, 5)));
56int ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen)
57	__attribute__((__bounded__(__buffer__, 3, 4)));
58
59/* Update API */
60struct ssh_digest_ctx *ssh_digest_start(int alg);
61int ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
62	__attribute__((__bounded__(__buffer__, 2, 3)));
63int ssh_digest_update_buffer(struct ssh_digest_ctx *ctx,
64    const struct sshbuf *b);
65int ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
66	__attribute__((__bounded__(__buffer__, 2, 3)));
67void ssh_digest_free(struct ssh_digest_ctx *ctx);
68
69#endif /* _DIGEST_H */
70
71