1 .\" Copyright 2000 Nicolás Lichtmaier <nick@debian.org>
2 .\" Created 2000-07-22 00:52-0300
4 .\" This is free documentation; you can redistribute it and/or
5 .\" modify it under the terms of the GNU General Public License as
6 .\" published by the Free Software Foundation; either version 2 of
7 .\" the License, or (at your option) any later version.
9 .\" The GNU General Public License's references to "object code"
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14 .\" This manual is distributed in the hope that it will be useful,
15 .\" but WITHOUT ANY WARRANTY; without even the implied warranty of
16 .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 .\" GNU General Public License for more details.
19 .\" Modified 2002-07-23 19:21:35 CEST 2002 Walter Harms
20 .\" <walter.harms@informatik.uni-oldenburg.de>
22 .\" Modified 2003-04-04, aeb
24 .TH ENCRYPT 3 2003-04-04 "" "Linux Programmer's Manual"
26 encrypt, setkey, encrypt_r, setkey_r \- encrypt 64-bit messages
28 .BR "#define _XOPEN_SOURCE" " /* See feature_test_macros(7) */"
30 .B #include <unistd.h>
32 .BI "void encrypt(char " block "[64], int " edflag );
34 .BR "#define _XOPEN_SOURCE" " /* See feature_test_macros(7) */"
36 .B #include <stdlib.h>
38 .BI "void setkey(const char *" key );
40 .BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */"
42 .B "#include <crypt.h>"
44 .BI "void setkey_r(const char *" key ", struct crypt_data *" data );
46 .BI "void encrypt_r(char *" block ", int " edflag \
47 ", struct crypt_data *" data );
49 Each of these requires linking with \fI\-lcrypt\fP.
51 These functions encrypt and decrypt 64-bit messages.
54 function sets the key used by
58 argument used here is an array of 64 bytes, each of which has
59 numerical value 1 or 0.
60 The bytes key[n] where n=8*i-1 are ignored,
61 so that the effective key length is 56 bits.
65 function modifies the passed buffer, encoding if
67 is 0, and decoding if 1 is being passed.
72 is a bit vector representation of the actual value that is encoded.
73 The result is returned in that same vector.
75 These two functions are not reentrant, that is, the key data is
76 kept in static storage.
81 are the reentrant versions.
82 They use the following
83 structure to hold the key data:
88 char keysched[16 * 8];
95 long int current_saltbits;
105 .I data\->initialized
108 These functions do not return any value.
112 to zero before calling the above functions.
113 On success, it is unchanged.
116 The function is not provided.
117 (For example because of former USA export restrictions.)
123 conform to SVr4, SUSv2, and POSIX.1-2001.
130 In glibc 2.2 these functions use the DES algorithm.
132 You need to link with libcrypt to compile this example with glibc.
133 To do useful work the
137 arrays must be filled with a useful bit pattern.
140 #define _XOPEN_SOURCE
147 char key[64]; /* bit pattern for key */
148 char txt[64]; /* bit pattern for messages */
151 encrypt(txt, 0); /* encode */
152 encrypt(txt, 1); /* decode */