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xcrypt - Man Page

RFS password encryption


Standard C library (libc, -lc)


#include <rpc/des_crypt.h>

void passwd2des(char *passwd, char *key);

int xencrypt(char *secret, char *passwd);
int xdecrypt(char *secret, char *passwd);


WARNING: Do not use these functions in new code. They do not achieve any type of acceptable cryptographic security guarantees.

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.

Return Value

The functions xencrypt() and xdecrypt() return 1 on success and 0 on error.


For an explanation of the terms used in this section, see attributes(7).

passwd2des(), xencrypt(), xdecrypt()Thread safetyMT-Safe


These functions are available since glibc 2.1.


The prototypes are missing from the abovementioned include file.

See Also


Referenced By


The man pages passwd2des(3), xdecrypt(3) and xencrypt(3) are aliases of xcrypt(3).

2024-05-02 Linux man-pages 6.8