115 lines
2.3 KiB
C
115 lines
2.3 KiB
C
/* crypt() - one-way password encryption function Author: Kees J. Bot
|
|
* 7 Feb 1994
|
|
* This routine does not encrypt anything, it uses the pwdauth
|
|
* program to do the hard work.
|
|
*/
|
|
#define nil ((void*)0)
|
|
#define pipe _pipe
|
|
#define fork _fork
|
|
#define close _close
|
|
#define dup2 _dup2
|
|
#define execl _execl
|
|
#define read _read
|
|
#define _exit __exit
|
|
#define write _write
|
|
#define waitpid _waitpid
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
#include <errno.h>
|
|
#include <stdarg.h>
|
|
#include <sys/wait.h>
|
|
|
|
/* Set-uid root program to read /etc/shadow or encrypt passwords. */
|
|
static char PWDAUTH[] = "/usr/lib/pwdauth";
|
|
#define LEN 1024
|
|
|
|
static void tell(const char *s0, ...)
|
|
{
|
|
va_list ap;
|
|
const char *s;
|
|
|
|
va_start(ap, s0);
|
|
s= s0;
|
|
while (s != nil) {
|
|
(void) write(2, s, strlen(s));
|
|
s= va_arg(ap, const char *);
|
|
}
|
|
va_end(ap);
|
|
}
|
|
|
|
char *crypt(const char *key, const char *salt)
|
|
{
|
|
pid_t pid;
|
|
int status;
|
|
int pfd[2];
|
|
static char pwdata[LEN];
|
|
char *p= pwdata;
|
|
const char *k= key;
|
|
const char *s= salt;
|
|
int n;
|
|
|
|
/* Fill pwdata[] with the key and salt. */
|
|
while ((*p++ = *k++) != 0) if (p == pwdata+LEN-1) goto fail;
|
|
while ((*p++ = *s++) != 0) if (p == pwdata+LEN-0) goto fail;
|
|
|
|
if (pipe(pfd) < 0) goto fail;
|
|
|
|
/* Prefill the pipe. */
|
|
(void) write(pfd[1], pwdata, p - pwdata);
|
|
|
|
switch ((pid= fork())) {
|
|
case -1:
|
|
close(pfd[0]);
|
|
close(pfd[1]);
|
|
goto fail;
|
|
case 0:
|
|
/* Connect both input and output to the pipe. */
|
|
if (pfd[0] != 0) {
|
|
dup2(pfd[0], 0);
|
|
close(pfd[0]);
|
|
}
|
|
if (pfd[1] != 1) {
|
|
dup2(pfd[1], 1);
|
|
close(pfd[1]);
|
|
}
|
|
|
|
execl(PWDAUTH, PWDAUTH, (char *) nil);
|
|
|
|
tell("crypt(): ", PWDAUTH, ": ", strerror(errno), "\r\n",
|
|
(char *) nil);
|
|
/* No pwdauth? Fail! */
|
|
(void) read(0, pwdata, LEN);
|
|
_exit(1);
|
|
}
|
|
close(pfd[1]);
|
|
|
|
status= -1;
|
|
while (waitpid(pid, &status, 0) == -1 && errno == EINTR) {}
|
|
if (status != 0) {
|
|
close(pfd[0]);
|
|
goto fail;
|
|
}
|
|
|
|
/* Read and return the result. Check if it contains exactly one
|
|
* string.
|
|
*/
|
|
n= read(pfd[0], pwdata, LEN);
|
|
close(pfd[0]);
|
|
if (n < 0) goto fail;
|
|
p = pwdata + n;
|
|
n = 0;
|
|
while (p > pwdata) if (*--p == 0) n++;
|
|
if (n != 1) goto fail;
|
|
return pwdata;
|
|
|
|
fail:
|
|
pwdata[0] = salt[0] ^ 1; /* make result != salt */
|
|
pwdata[1] = 0;
|
|
return pwdata;
|
|
}
|
|
|
|
/*
|
|
* $PchId: crypt.c,v 1.5 1996/04/11 07:46:11 philip Exp $
|
|
*/
|