xref: /openssh-portable/digest.h (revision 7bdb2eeb)
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 
32 struct sshbuf;
33 struct ssh_digest_ctx;
34 
35 /* Looks up a digest algorithm by name */
36 int ssh_digest_alg_by_name(const char *name);
37 
38 /* Returns the algorithm name for a digest identifier */
39 const char *ssh_digest_alg_name(int alg);
40 
41 /* Returns the algorithm's digest length in bytes or 0 for invalid algorithm */
42 size_t ssh_digest_bytes(int alg);
43 
44 /* Returns the block size of the digest, e.g. for implementing HMAC */
45 size_t ssh_digest_blocksize(struct ssh_digest_ctx *ctx);
46 
47 /* Copies internal state of digest of 'from' to 'to' */
48 int ssh_digest_copy_state(struct ssh_digest_ctx *from,
49     struct ssh_digest_ctx *to);
50 
51 /* One-shot API */
52 int 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)));
56 int 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 */
60 struct ssh_digest_ctx *ssh_digest_start(int alg);
61 int ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
62 	__attribute__((__bounded__(__buffer__, 2, 3)));
63 int ssh_digest_update_buffer(struct ssh_digest_ctx *ctx,
64     const struct sshbuf *b);
65 int ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
66 	__attribute__((__bounded__(__buffer__, 2, 3)));
67 void ssh_digest_free(struct ssh_digest_ctx *ctx);
68 
69 #endif /* _DIGEST_H */
70 
71