1/* Declaration of functions and data types used for MD5 sum computing
2   library functions.
3   Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
4   This file is part of the GNU C Library.
5
6   The GNU C Library is free software; you can redistribute it and/or
7   modify it under the terms of the GNU Library General Public License as
8   published by the Free Software Foundation; either version 2 of the
9   License, or (at your option) any later version.
10
11   The GNU C Library 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 GNU
14   Library General Public License for more details.
15
16   You should have received a copy of the GNU Library General Public
17   License along with the GNU C Library; see the file COPYING.LIB.  If not,
18   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19   Boston, MA 02111-1307, USA.  */
20
21#ifndef _MD5_H
22#define _MD5_H 1
23
24#include <stdio.h>
25
26#if defined HAVE_LIMITS_H || _LIBC
27# include <limits.h>
28#endif
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>
39typedef u_int32_t md5_uint32;
40#else
41# if defined __STDC__ && __STDC__
42#  define UINT_MAX_32_BITS 4294967295U
43# else
44#  define UINT_MAX_32_BITS 0xFFFFFFFF
45# endif
46
47/* If UINT_MAX isn't defined, assume it's a 32-bit type.
48   This should be valid for all systems GNU cares about because
49   that doesn't include 16-bit systems, and only modern systems
50   (that certainly have <limits.h>) have 64+-bit integral types.  */
51
52# ifndef UINT_MAX
53#  define UINT_MAX UINT_MAX_32_BITS
54# endif
55
56# if UINT_MAX == UINT_MAX_32_BITS
57   typedef unsigned int md5_uint32;
58# else
59#  if USHRT_MAX == UINT_MAX_32_BITS
60    typedef unsigned short md5_uint32;
61#  else
62#   if ULONG_MAX == UINT_MAX_32_BITS
63     typedef unsigned long md5_uint32;
64#   else
65     /* The following line is intended to evoke an error.
66        Using #error is not portable enough.  */
67     "Cannot determine unsigned 32-bit data type."
68#   endif
69#  endif
70# endif
71#endif
72
73#undef __P
74#if defined (__STDC__) && __STDC__
75# define __P(x) x
76#else
77# define __P(x) ()
78#endif
79
80/* Structure to save state of computation between the single steps.  */
81struct md5_ctx
82{
83  md5_uint32 A;
84  md5_uint32 B;
85  md5_uint32 C;
86  md5_uint32 D;
87
88  md5_uint32 total[2];
89  md5_uint32 buflen;
90  char buffer[128];
91};
92
93/*
94 * The following three functions are build up the low level used in
95 * the functions `md5_stream' and `md5_buffer'.
96 */
97
98/* Initialize structure containing state of computation.
99   (RFC 1321, 3.3: Step 3)  */
100extern void __md5_init_ctx __P ((struct md5_ctx *ctx));
101extern void md5_init_ctx __P ((struct md5_ctx *ctx));
102
103/* Starting with the result of former calls of this function (or the
104   initialization function update the context for the next LEN bytes
105   starting at BUFFER.
106   It is necessary that LEN is a multiple of 64!!! */
107extern void __md5_process_block __P ((const void *buffer, size_t len,
108				      struct md5_ctx *ctx));
109extern void md5_process_block __P ((const void *buffer, size_t len,
110				    struct md5_ctx *ctx));
111
112/* Starting with the result of former calls of this function (or the
113   initialization function update the context for the next LEN bytes
114   starting at BUFFER.
115   It is NOT required that LEN is a multiple of 64.  */
116extern void __md5_process_bytes __P ((const void *buffer, size_t len,
117				      struct md5_ctx *ctx));
118extern void md5_process_bytes __P ((const void *buffer, size_t len,
119				    struct md5_ctx *ctx));
120
121/* Process the remaining bytes in the buffer and put result from CTX
122   in first 16 bytes following RESBUF.  The result is always in little
123   endian byte order, so that a byte-wise output yields to the wanted
124   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 *__md5_finish_ctx __P ((struct md5_ctx *ctx, void *resbuf));
129extern void *md5_finish_ctx __P ((struct md5_ctx *ctx, void *resbuf));
130
131
132/* Put result from CTX in first 16 bytes following RESBUF.  The result is
133   always in little endian byte order, so that a byte-wise output yields
134   to the wanted ASCII representation of the message digest.
135
136   IMPORTANT: On some systems it is required that RESBUF is correctly
137   aligned for a 32 bits value.  */
138extern void *__md5_read_ctx __P ((const struct md5_ctx *ctx, void *resbuf));
139extern void *md5_read_ctx __P ((const struct md5_ctx *ctx, void *resbuf));
140
141
142/* Compute MD5 message digest for bytes read from STREAM.  The
143   resulting message digest number will be written into the 16 bytes
144   beginning at RESBLOCK.  */
145extern int __md5_stream __P ((FILE *stream, void *resblock));
146
147/* Compute MD5 message digest for LEN bytes beginning at BUFFER.  The
148   result is always in little endian byte order, so that a byte-wise
149   output yields to the wanted ASCII representation of the message
150   digest.  */
151extern void *__md5_buffer __P ((const char *buffer, size_t len,
152				void *resblock));
153extern void *md5_buffer __P ((const char *buffer, size_t len,
154			      void *resblock));
155
156#endif /* md5.h */
157