digest.h

   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