include/sha1.h

   1 /* Declarations of functions and data types used for SHA1 sum
   2    library functions.
   3    Copyright (C) 2000, 2001, 2003, 2005, 2006, 2008, 2010
   4    Free Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published by the
   8    Free Software Foundation; either version 3, or (at your option) any
   9    later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  19
  20 #ifndef SHA1_H
  21 # define SHA1_H 1
  22
  23 #include <stdio.h>
  24
  25 #if defined HAVE_LIMITS_H || _LIBC
  26 # include <limits.h>
  27 #endif
  28
  29 #include "ansidecl.h"
  30
  31 /* The following contortions are an attempt to use the C preprocessor
  32    to determine an unsigned integral type that is 32 bits wide.  An
  33    alternative approach is to use autoconf's AC_CHECK_SIZEOF macro, but
  34    doing that would require that the configure script compile and *run*
  35    the resulting executable.  Locally running cross-compiled executables
  36    is usually not possible.  */
  37
  38 #ifdef _LIBC
  39 # include <sys/types.h>
  40 typedef u_int32_t sha1_uint32;
  41 typedef uintptr_t sha1_uintptr;
  42 #elif defined (HAVE_SYS_TYPES_H) && defined (HAVE_STDINT_H)
  43 #include <stdint.h>
  44 #include <sys/types.h>
  45 typedef uint32_t sha1_uint32;
  46 typedef uintptr_t sha1_uintptr;
  47 #else
  48 #  define INT_MAX_32_BITS 2147483647
  49
  50 /* If UINT_MAX isn't defined, assume it's a 32-bit type.
  51    This should be valid for all systems GNU cares about because
  52    that doesn't include 16-bit systems, and only modern systems
  53    (that certainly have <limits.h>) have 64+-bit integral types.  */
  54
  55 # ifndef INT_MAX
  56 #  define INT_MAX INT_MAX_32_BITS
  57 # endif
  58
  59 # if INT_MAX == INT_MAX_32_BITS
  60    typedef unsigned int sha1_uint32;
  61 # else
  62 #  if SHRT_MAX == INT_MAX_32_BITS
  63     typedef unsigned short sha1_uint32;
  64 #  else
  65 #   if LONG_MAX == INT_MAX_32_BITS
  66      typedef unsigned long sha1_uint32;
  67 #   else
  68      /* The following line is intended to evoke an error.
  69         Using #error is not portable enough.  */
  70      "Cannot determine unsigned 32-bit data type."
  71 #   endif
  72 #  endif
  73 # endif
  74 #endif
  75
  76 #ifdef __cplusplus
  77 extern "C" {
  78 #endif
  79
  80 /* Structure to save state of computation between the single steps.  */
  81 struct sha1_ctx
  82 {
  83   sha1_uint32 A;
  84   sha1_uint32 B;
  85   sha1_uint32 C;
  86   sha1_uint32 D;
  87   sha1_uint32 E;
  88
  89   sha1_uint32 total[2];
  90   sha1_uint32 buflen;
  91   sha1_uint32 buffer[32];
  92 };
  93
  94
  95 /* Initialize structure containing state of computation. */
  96 extern void sha1_init_ctx (struct sha1_ctx *ctx);
  97
  98 /* Starting with the result of former calls of this function (or the
  99    initialization function update the context for the next LEN bytes
 100    starting at BUFFER.
 101    It is necessary that LEN is a multiple of 64!!! */
 102 extern void sha1_process_block (const void *buffer, size_t len,
 103                                 struct sha1_ctx *ctx);
 104
 105 /* Starting with the result of former calls of this function (or the
 106    initialization function update the context for the next LEN bytes
 107    starting at BUFFER.
 108    It is NOT required that LEN is a multiple of 64.  */
 109 extern void sha1_process_bytes (const void *buffer, size_t len,
 110                                 struct sha1_ctx *ctx);
 111
 112 /* Process the remaining bytes in the buffer and put result from CTX
 113    in first 20 bytes following RESBUF.  The result is always in little
 114    endian byte order, so that a byte-wise output yields to the wanted
 115    ASCII representation of the message digest.
 116
 117    IMPORTANT: On some systems it is required that RESBUF be correctly
 118    aligned for a 32 bits value.  */
 119 extern void *sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf);
 120
 121
 122 /* Put result from CTX in first 20 bytes following RESBUF.  The result is
 123    always in little endian byte order, so that a byte-wise output yields
 124    to the wanted ASCII representation of the message digest.
 125
 126    IMPORTANT: On some systems it is required that RESBUF is correctly
 127    aligned for a 32 bits value.  */
 128 extern void *sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf);
 129
 130
 131 /* Compute SHA1 message digest for bytes read from STREAM.  The
 132    resulting message digest number will be written into the 20 bytes
 133    beginning at RESBLOCK.  */
 134 extern int sha1_stream (FILE *stream, void *resblock);
 135
 136 /* Compute SHA1 message digest for LEN bytes beginning at BUFFER.  The
 137    result is always in little endian byte order, so that a byte-wise
 138    output yields to the wanted ASCII representation of the message
 139    digest.  */
 140 extern void *sha1_buffer (const char *buffer, size_t len, void *resblock);
 141
 142 #ifdef __cplusplus
 143 }
 144 #endif
 145
 146 #endif