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>
40typedef u_int32_t sha1_uint32;
41typedef uintptr_t sha1_uintptr;
42#elif defined (HAVE_SYS_TYPES_H) && defined (HAVE_STDINT_H)
43#include <stdint.h>
44#include <sys/types.h>
45typedef uint32_t sha1_uint32;
46typedef 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
77extern "C" {
78#endif
79
80/* Structure to save state of computation between the single steps.  */
81struct 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. */
96extern 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!!! */
102extern 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.  */
109extern 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.  */
119extern 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.  */
128extern 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.  */
134extern 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.  */
140extern void *sha1_buffer (const char *buffer, size_t len, void *resblock);
141
142#ifdef __cplusplus
143}
144#endif
145
146#endif
147