XCRYPT(3) Linux Programmers Manual XCRYPT(3)
xencrypt, xdecrypt, passwd2des - RFS password encryption
void passwd2des(char *passwd, char *key);
int xencrypt(char *secret, char *passwd);
int xdecrypt(char *secret, char *passwd);
The function passwd2des() takes a character string passwd of arbitrary
length and fills a character array key of length 8. The array key is
suitable for use as DES key. It has odd parity set in bit 0 of each
byte. Both other functions described here use this function to turn
their argument passwd into a DES key.
The xencrypt() function takes the ASCII character string secret given
in hex, which must have a length that is a multiple of 16, encrypts it
using the DES key derived from passwd by passwd2des(), and outputs the
result again in secret as a hex string of the same length.
The xdecrypt() function performs the converse operation.
The functions xencrypt() and xdecrypt() return 1 on success and 0 on
These routines are present in libc 4.6.27 and later, and in glibc 2.1
The prototypes are missing from the abovementioned include file.
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