shadow/libmisc/salt.c

47 lines
1.1 KiB
C

/*
* salt.c - generate a random salt string for crypt()
*
* Written by Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>,
* public domain.
*/
#include <config.h>
#ident "$Id: salt.c,v 1.10 2005/08/31 17:24:58 kloczek Exp $"
#include <sys/time.h>
#include <stdlib.h>
#include "prototypes.h"
#include "defines.h"
#include "getdef.h"
/*
* Generate 8 base64 ASCII characters of random salt. If MD5_CRYPT_ENAB
* in /etc/login.defs is "yes", the salt string will be prefixed by "$1$"
* (magic) and pw_encrypt() will execute the MD5-based FreeBSD-compatible
* version of crypt() instead of the standard one.
*/
char *crypt_make_salt (void)
{
struct timeval tv;
static char result[40];
result[0] = '\0';
#ifndef USE_PAM
if (getdef_bool ("MD5_CRYPT_ENAB")) {
strcpy (result, "$1$"); /* magic for the new MD5 crypt() */
}
#endif
/*
* Generate 8 chars of salt, the old crypt() will use only first 2.
*/
gettimeofday (&tv, (struct timezone *) 0);
strcat (result, l64a (tv.tv_usec));
strcat (result, l64a (tv.tv_sec + getpid () + clock ()));
if (strlen (result) > 3 + 8) /* magic+salt */
result[11] = '\0';
return result;
}