usr.bin/key/skey.c

   1 /* Stand-alone program for computing responses to S/Key challenges.
   2  * Takes the iteration count and seed as command line args, prompts
   3  * for the user's key, and produces both word and hex format responses.
   4  *
   5  * Usage example:
   6  *      >skey 88 ka9q2
   7  *      Enter password:
   8  *      OMEN US HORN OMIT BACK AHOY
   9  *      C848 666B 6435 0A93
  10  *      >
  11  *
  12  * $FreeBSD: src/usr.bin/key/skey.c,v 1.6.6.1 2001/03/04 08:35:48 kris Exp $
  13  * $DragonFly: src/usr.bin/key/skey.c,v 1.3 2003/10/04 20:36:46 hmp Exp $
  14  */
  15
  16 #include <err.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <unistd.h>
  21
  22 #ifdef  __MSDOS__
  23 #include <dos.h>
  24 #else   /* Assume BSD Unix */
  25 #include <fcntl.h>
  26 #endif
  27
  28 #include <skey.h>
  29
  30 static void usage(void);
  31
  32 int
  33 main(int argc, char **argv)
  34 {
  35         int n,cnt,i;
  36         char passwd[256] /* ,passwd2[256] */;
  37         char key[8];
  38         char *seed;
  39         char buf[33];
  40         char *slash;
  41
  42         cnt = 1;
  43         while((i = getopt(argc,argv,"n:")) != -1){
  44                 switch(i){
  45                 case 'n':
  46                         cnt = atoi(optarg);
  47                         break;
  48                 }
  49         }
  50         /* could be in the form <number>/<seed> */
  51         if(argc <= optind + 1){
  52                 /*look for / in it */
  53                 if(argc <= optind)
  54                         usage();
  55
  56                 slash = strchr(argv[optind], '/');
  57                 if(slash == NULL)
  58                         usage();
  59                 *slash++ = '\0';
  60                 seed = slash;
  61
  62                 if((n = atoi(argv[optind])) < 0){
  63                         warnx("%s not positive",argv[optind]);
  64                         usage();
  65                 }
  66         }
  67         else {
  68
  69                 if((n = atoi(argv[optind])) < 0){
  70                         warnx("%s not positive",argv[optind]);
  71                         usage();
  72                 }
  73                 seed = argv[++optind];
  74         }
  75         fprintf(stderr,"Reminder - Do not use this program while logged in via telnet or rlogin.\n");
  76
  77         /* Get user's secret password */
  78         for(;;){
  79                 fprintf(stderr,"Enter secret password: ");
  80                 readpass(passwd,sizeof(passwd));
  81                 break;
  82         /************
  83                 fprintf(stderr,"Again secret password: ");
  84                 readpass(passwd2,sizeof(passwd));
  85                 if(strcmp(passwd,passwd2) == 0) break;
  86                 fprintf(stderr, "Sorry no match\n");
  87         **************/
  88
  89         }
  90
  91         /* Crunch seed and password into starting key */
  92         if(keycrunch(key,seed,passwd) != 0)
  93                 errx(1, "key crunch failed");
  94         if(cnt == 1){
  95                 while(n-- != 0)
  96                         f(key);
  97                 printf("%s\n",btoe(buf,key));
  98 #ifdef  HEXIN
  99                 printf("%s\n",put8(buf,key));
 100 #endif
 101         } else {
 102                 for(i=0;i<=n-cnt;i++)
 103                         f(key);
 104                 for(;i<=n;i++){
 105 #ifdef  HEXIN
 106                         printf("%d: %-29s  %s\n",i,btoe(buf,key),put8(buf,key));
 107 #else
 108                         printf("%d: %-29s\n",i,btoe(buf,key));
 109 #endif
 110                         f(key);
 111                 }
 112         }
 113         return 0;
 114 }
 115
 116 static void
 117 usage(void)
 118 {
 119         fprintf(stderr,"usage: key [-n count] <sequence #>[/] <key>\n");
 120         exit(1);
 121 }