freebsd-src/usr.bin/key/skey.c
1997-07-16 06:51:12 +00:00

121 lines
2.3 KiB
C

/* Stand-alone program for computing responses to S/Key challenges.
* Takes the iteration count and seed as command line args, prompts
* for the user's key, and produces both word and hex format responses.
*
* Usage example:
* >skey 88 ka9q2
* Enter password:
* OMEN US HORN OMIT BACK AHOY
* C848 666B 6435 0A93
* >
*/
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef __MSDOS__
#include <dos.h>
#else /* Assume BSD unix */
#include <fcntl.h>
#endif
#include <skey.h>
static void usage __P((void));
int
main(argc,argv)
int argc;
char *argv[];
{
int n,cnt,i;
char passwd[256] /* ,passwd2[256] */;
char key[8];
char *seed;
char buf[33];
char *slash;
cnt = 1;
while((i = getopt(argc,argv,"n:")) != -1){
switch(i){
case 'n':
cnt = atoi(optarg);
break;
}
}
/* could be in the form <number>/<seed> */
if(argc <= optind + 1){
/*look for / in it */
if(argc <= optind)
usage();
slash = strchr(argv[optind], '/');
if(slash == NULL)
usage();
*slash++ = '\0';
seed = slash;
if((n = atoi(argv[optind])) < 0){
fprintf(stderr,"%s not positive\n",argv[optind]);
usage();
}
}
else {
if((n = atoi(argv[optind])) < 0){
fprintf(stderr,"%s not positive\n",argv[optind]);
usage();
}
seed = argv[++optind];
}
fprintf(stderr,"Reminder - Do not use this program while logged in via telnet or rlogin.\n");
/* Get user's secret password */
for(;;){
fprintf(stderr,"Enter secret password: ");
readpass(passwd,sizeof(passwd));
break;
/************
fprintf(stderr,"Again secret password: ");
readpass(passwd2,sizeof(passwd));
if(strcmp(passwd,passwd2) == 0) break;
fprintf(stderr, "Sorry no match\n");
**************/
}
/* Crunch seed and password into starting key */
if(keycrunch(key,seed,passwd) != 0)
errx(1, "key crunch failed");
if(cnt == 1){
while(n-- != 0)
f(key);
printf("%s\n",btoe(buf,key));
#ifdef HEXIN
printf("%s\n",put8(buf,key));
#endif
} else {
for(i=0;i<=n-cnt;i++)
f(key);
for(;i<=n;i++){
#ifdef HEXIN
printf("%d: %-29s %s\n",i,btoe(buf,key),put8(buf,key));
#else
printf("%d: %-29s\n",i,btoe(buf,key));
#endif
f(key);
}
}
return 0;
}
static void
usage()
{
fprintf(stderr,"usage: key [-n count] <sequence #>[/] <key>\n");
exit(1);
}