1 /* Declarations of functions and data types used for SHA1 sum
2    library functions.
3    Copyright (C) 2000-2019 Free Software Foundation, Inc.
4 
5    This program is free software; you can redistribute it and/or modify it
6    under the terms of the GNU General Public License as published by the
7    Free Software Foundation; either version 3, or (at your option) any
8    later version.
9 
10    This program is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13    GNU General Public License for more details.
14 
15    You should have received a copy of the GNU General Public License
16    along with this program; if not, write to the Free Software Foundation,
17    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
18 
19 #ifndef SHA1_H
20 # define SHA1_H 1
21 
22 #include <stdio.h>
23 
24 #if defined HAVE_LIMITS_H || _LIBC
25 # include <limits.h>
26 #endif
27 
28 #include "ansidecl.h"
29 
30 /* The following contortions are an attempt to use the C preprocessor
31    to determine an unsigned integral type that is 32 bits wide.  An
32    alternative approach is to use autoconf's AC_CHECK_SIZEOF macro, but
33    doing that would require that the configure script compile and *run*
34    the resulting executable.  Locally running cross-compiled executables
35    is usually not possible.  */
36 
37 #ifdef _LIBC
38 # include <sys/types.h>
39 typedef u_int32_t sha1_uint32;
40 typedef uintptr_t sha1_uintptr;
41 #elif defined (HAVE_SYS_TYPES_H) && defined (HAVE_STDINT_H)
42 #include <stdint.h>
43 #include <sys/types.h>
44 typedef uint32_t sha1_uint32;
45 typedef uintptr_t sha1_uintptr;
46 #else
47 #  define INT_MAX_32_BITS 2147483647
48 
49 /* If UINT_MAX isn't defined, assume it's a 32-bit type.
50    This should be valid for all systems GNU cares about because
51    that doesn't include 16-bit systems, and only modern systems
52    (that certainly have <limits.h>) have 64+-bit integral types.  */
53 
54 # ifndef INT_MAX
55 #  define INT_MAX INT_MAX_32_BITS
56 # endif
57 
58 # if INT_MAX == INT_MAX_32_BITS
59    typedef unsigned int sha1_uint32;
60 # else
61 #  if SHRT_MAX == INT_MAX_32_BITS
62     typedef unsigned short sha1_uint32;
63 #  else
64 #   if LONG_MAX == INT_MAX_32_BITS
65      typedef unsigned long sha1_uint32;
66 #   else
67      /* The following line is intended to evoke an error.
68         Using #error is not portable enough.  */
69      "Cannot determine unsigned 32-bit data type."
70 #   endif
71 #  endif
72 # endif
73 #endif
74 
75 #ifdef __cplusplus
76 extern "C" {
77 #endif
78 
79 /* Structure to save state of computation between the single steps.  */
80 struct sha1_ctx
81 {
82   sha1_uint32 A;
83   sha1_uint32 B;
84   sha1_uint32 C;
85   sha1_uint32 D;
86   sha1_uint32 E;
87 
88   sha1_uint32 total[2];
89   sha1_uint32 buflen;
90   sha1_uint32 buffer[32];
91 };
92 
93 
94 /* Initialize structure containing state of computation. */
95 extern void sha1_init_ctx (struct sha1_ctx *ctx);
96 
97 /* Starting with the result of former calls of this function (or the
98    initialization function update the context for the next LEN bytes
99    starting at BUFFER.
100    It is necessary that LEN is a multiple of 64!!! */
101 extern void sha1_process_block (const void *buffer, size_t len,
102 				struct sha1_ctx *ctx);
103 
104 /* Starting with the result of former calls of this function (or the
105    initialization function update the context for the next LEN bytes
106    starting at BUFFER.
107    It is NOT required that LEN is a multiple of 64.  */
108 extern void sha1_process_bytes (const void *buffer, size_t len,
109 				struct sha1_ctx *ctx);
110 
111 /* Process the remaining bytes in the buffer and put result from CTX
112    in first 20 bytes following RESBUF.  The result is always in little
113    endian byte order, so that a byte-wise output yields to the wanted
114    ASCII representation of the message digest.
115 
116    IMPORTANT: On some systems it is required that RESBUF be correctly
117    aligned for a 32 bits value.  */
118 extern void *sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf);
119 
120 
121 /* Put result from CTX in first 20 bytes following RESBUF.  The result is
122    always in little endian byte order, so that a byte-wise output yields
123    to the wanted ASCII representation of the message digest.
124 
125    IMPORTANT: On some systems it is required that RESBUF is correctly
126    aligned for a 32 bits value.  */
127 extern void *sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf);
128 
129 
130 /* Compute SHA1 message digest for bytes read from STREAM.  The
131    resulting message digest number will be written into the 20 bytes
132    beginning at RESBLOCK.  */
133 extern int sha1_stream (FILE *stream, void *resblock);
134 
135 /* Compute SHA1 message digest for LEN bytes beginning at BUFFER.  The
136    result is always in little endian byte order, so that a byte-wise
137    output yields to the wanted ASCII representation of the message
138    digest.  */
139 extern void *sha1_buffer (const char *buffer, size_t len, void *resblock);
140 
141 #ifdef __cplusplus
142 }
143 #endif
144 
145 #endif
146