1DES_CRYPT(3)               Library Functions Manual               DES_CRYPT(3)
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NAME

6       des_crypt,  ecb_crypt,  cbc_crypt, des_setparity, DES_FAILED - fast DES
7       encryption
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SYNOPSIS

10       #include <rpc/des_crypt.h>
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12       int ecb_crypt(char *key, char *data, unsigned datalen,
13                     unsigned mode);
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15       int cbc_crypt(char *key, char *data, unsigned datalen,
16                     unsigned mode, char *ivec);
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18       void des_setparity(char *key);
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20       int DES_FAILED(int status);
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DESCRIPTION

23       ecb_crypt() and cbc_crypt() implement  the  NBS  DES  (Data  Encryption
24       Standard).   These  routines  are  faster and more general purpose than
25       crypt(3).  They also are able to utilize DES hardware if it  is  avail‐
26       able.   ecb_crypt()  encrypts in ECB (Electronic Code Book) mode, which
27       encrypts blocks of data independently.   cbc_crypt()  encrypts  in  CBC
28       (Cipher  Block Chaining) mode, which chains together successive blocks.
29       CBC mode protects against insertions, deletions  and  substitutions  of
30       blocks.  Also,  regularities  in  the clear text will not appear in the
31       cipher text.
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33       Here is how to use these routines.  The first parameter,  key,  is  the
34       8-byte  encryption key with parity.  To set the key's parity, which for
35       DES is in the low bit of each byte, use  des_setparity().   The  second
36       parameter,  data,  contains  the data to be encrypted or decrypted. The
37       third parameter, datalen, is the length in bytes of data, which must be
38       a  multiple  of  8.  The  fourth  parameter,  mode, is formed by OR'ing
39       together some things.  For the  encryption  direction  'or'  in  either
40       DES_ENCRYPT  or  DES_DECRYPT.  For software versus hardware encryption,
41       'or' in either DES_HW or DES_SW.  If DES_HW is specified, and there  is
42       no  hardware, then the encryption is performed in software and the rou‐
43       tine returns DESERR_NOHWDEVICE.  For cbc_crypt(), the parameter ivec is
44       the  8-byte  initialization  vector for the chaining.  It is updated to
45       the next initialization vector upon return.
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SEE ALSO

48       des(1), crypt(3) and xcrypt(3)
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DIAGNOSTICS

51       DESERR_NONE         No error.
52       DESERR_NOHWDEVICE   Encryption succeeded, but done in software  instead
53                           of the requested hardware.
54       DESERR_HWERROR      An error occurred in the hardware or driver.
55       DESERR_BADPARAM     Bad parameter to routine.
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57       Given  a  result  status stat, the macro DES_FAILED(stat) is false only
58       for the first two statuses.
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AVAILABILITY

62       These routines are present in libc 4.6.27 and later, and in  glibc  2.1
63       and later.
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CONFORMING TO

66       4.3BSD.  Not in POSIX.1-2001.
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71                                6 October 1987                    DES_CRYPT(3)