mdw@git.distorted.org.uk Git - runlisp/blob - sha256.h

   1 /* -*-c-*-
   2  *
   3  * The SHA256 hash function
   4  *
   5  * (c) 2020 Mark Wooding
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Runlisp, a tool for invoking Common Lisp scripts.
  11  *
  12  * Runlisp is free software: you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * Runlisp is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with Runlisp.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 #ifndef SHA256_H
  27 #define SHA256_H
  28
  29 #ifdef __cplusplus
  30   extern "C" {
  31 #endif
  32
  33 /*----- Header files ------------------------------------------------------*/
  34
  35 #include <limits.h>
  36
  37 /*----- Data types --------------------------------------------------------*/
  38
  39 /* Select a suitable type for 32-bit words. */
  40 #if UINT_MAX >= 0xffffffff
  41   typedef unsigned u32;
  42 #else
  43   typedef unsigned long u32;
  44 #endif
  45
  46 #define SHA256_BLKSZ 64                 /* input block size in bytes */
  47 #define SHA256_HASHSZ 32                /* output hash size in bytes */
  48
  49 struct sha256_state {
  50   unsigned n;                           /* number of live bytes in buffer */
  51   size_t nblk;                          /* number of blocks hashed so far */
  52   u32 a[8];                             /* hash state */
  53   unsigned char buf[SHA256_BLKSZ];      /* input buffer */
  54 };
  55
  56 /*----- Functions provided ------------------------------------------------*/
  57
  58 extern void sha256_init(struct sha256_state */**/);
  59         /* Initialize the hash state S. */
  60
  61 extern void sha256_hash(struct sha256_state */*s*/,
  62                         const void */*m*/, size_t /*sz*/);
  63         /* Append SZ bytes of data starting at M to the hash state S. */
  64
  65 extern void sha256_done(struct sha256_state */*s*/, unsigned char */*h*/);
  66         /* Write the final hash of state S to buffer H. */
  67
  68 /*----- That's all, folks -------------------------------------------------*/
  69
  70 #ifdef __cplusplus
  71   }
  72 #endif
  73
  74 #endif