1 /* 2 * S/KEY v1.1b (skey.c) 3 * 4 * Authors: 5 * Neil M. Haller <nmh@thumper.bellcore.com> 6 * Philip R. Karn <karn@chicago.qualcomm.com> 7 * John S. Walden <jsw@thumper.bellcore.com> 8 * Scott Chasin <chasin@crimelab.com> 9 * 10 * 11 * Stand-alone program for computing responses to S/Key challenges. 12 * Takes the iteration count and seed as command line args, prompts 13 * for the user's key, and produces both word and hex format responses. 14 * 15 * Usage example: 16 * >skey 88 ka9q2 17 * Enter password: 18 * OMEN US HORN OMIT BACK AHOY 19 * > 20 * 21 * $Id: skey.c,v 1.2 1994/12/28 23:17:52 cgd Exp $ 22 */ 23 24 #include <stdio.h> 25 #include <stdlib.h> 26 #include <string.h> 27 #include <fcntl.h> 28 #include <sgtty.h> 29 #include "md4.h" 30 #include "skey.h" 31 32 char *readpass(); 33 void usage(); 34 35 main(argc, argv) 36 int argc; 37 char *argv[]; 38 { 39 int n, cnt, i, pass = 0; 40 char passwd[256], key[8], buf[33], *seed, *slash; 41 extern int optind; 42 extern char *optarg; 43 44 cnt = 1; 45 46 while ((i = getopt(argc, argv, "n:p:")) != EOF) { 47 switch (i) { 48 case 'n': 49 cnt = atoi(optarg); 50 break; 51 case 'p': 52 strcpy(passwd, optarg); 53 pass = 1; 54 break; 55 } 56 } 57 58 /* could be in the form <number>/<seed> */ 59 60 if (argc <= optind + 1) { 61 /* look for / in it */ 62 if (argc <= optind) 63 usage(argv[0]); 64 slash = strchr(argv[optind], '/'); 65 if (slash == NULL) 66 usage(argv[0]); 67 *slash++ = '\0'; 68 seed = slash; 69 70 if ((n = atoi(argv[optind])) < 0) { 71 fprintf(stderr, "%s not positive\n", argv[optind]); 72 usage(argv[0]); 73 } 74 } else { 75 76 if ((n = atoi(argv[optind])) < 0) { 77 fprintf(stderr, "%s not positive\n", argv[optind]); 78 usage(argv[0]); 79 } 80 seed = argv[++optind]; 81 } 82 83 /* Get user's secret password */ 84 if (!pass) { 85 fprintf(stderr, "Enter secret password: "); 86 readpass(passwd, sizeof(passwd)); 87 } 88 rip(passwd); 89 90 /* Crunch seed and password into starting key */ 91 if (keycrunch(key, seed, passwd) != 0) { 92 fprintf(stderr, "%s: key crunch failed\n", argv[0]); 93 exit(1); 94 } 95 if (cnt == 1) { 96 while (n-- != 0) 97 f(key); 98 printf("%s\n", btoe(buf, key)); 99 #ifdef HEXIN 100 printf("%s\n", put8(buf, key)); 101 #endif 102 } else { 103 for (i = 0; i <= n - cnt; i++) 104 f(key); 105 for (; i <= n; i++) { 106 #ifdef HEXIN 107 printf("%d: %-29s %s\n", i, btoe(buf, key), put8(buf, key)); 108 #else 109 printf("%d: %-29s\n", i, btoe(buf, key)); 110 #endif 111 f(key); 112 } 113 } 114 exit(0); 115 } 116 117 void 118 usage(s) 119 char *s; 120 { 121 122 fprintf(stderr, 123 "Usage: %s [-n count] [-p password ] sequence# [/] key\n", s); 124 exit(1); 125 } 126