1 /* 2 * "enigma.c" is in file cbw.tar from 3 * anonymous FTP host watmsg.waterloo.edu: pub/crypt/cbw.tar.Z 4 * 5 * A one-rotor machine designed along the lines of Enigma 6 * but considerably trivialized. 7 * 8 * A public-domain replacement for the UNIX "crypt" command. 9 * 10 * Upgraded to function properly on 64-bit machines. 11 * 12 * $FreeBSD: src/usr.bin/enigma/enigma.c,v 1.2.6.3 2001/08/01 23:51:34 obrien Exp $ 13 * $DragonFly: src/usr.bin/enigma/enigma.c,v 1.6 2005/01/05 18:42:33 liamfoy Exp $ 14 */ 15 16 #include <stdio.h> 17 #include <stdlib.h> 18 #include <string.h> 19 #include <unistd.h> 20 21 #define MINUSKVAR "CrYpTkEy" 22 23 #define ECHO 010 24 #define ROTORSZ 256 25 #define MASK 0377 26 char t1[ROTORSZ]; 27 char t2[ROTORSZ]; 28 char t3[ROTORSZ]; 29 char deck[ROTORSZ]; 30 char buf[13]; 31 32 static void shuffle(char *); 33 static void setup(const char *); 34 35 static void 36 setup(const char *pw) 37 { 38 int ic, i, k, temp; 39 char salt[3]; 40 unsigned rnd; 41 long seed; 42 char *cryptpw; 43 44 strncpy(salt, pw, sizeof(salt)); 45 cryptpw = crypt(pw, salt); 46 if (cryptpw == NULL) { 47 fprintf(stderr, "crypt(3) failure\n"); 48 exit(1); 49 } 50 memcpy(buf, cryptpw, sizeof(buf)); 51 seed = 123; 52 for (i=0; i<13; i++) 53 seed = seed*buf[i] + i; 54 for(i=0;i<ROTORSZ;i++) { 55 t1[i] = i; 56 deck[i] = i; 57 } 58 for(i=0;i<ROTORSZ;i++) { 59 seed = 5*seed + buf[i%13]; 60 if( sizeof(long) > 4 ) { 61 /* Force seed to stay in 32-bit signed math */ 62 if( seed & 0x80000000 ) 63 seed = seed | (-1L & ~0xFFFFFFFFL); 64 else 65 seed &= 0x7FFFFFFF; 66 } 67 rnd = seed % 65521; 68 k = ROTORSZ-1 - i; 69 ic = (rnd&MASK)%(k+1); 70 rnd >>= 8; 71 temp = t1[k]; 72 t1[k] = t1[ic]; 73 t1[ic] = temp; 74 if(t3[k]!=0) continue; 75 ic = (rnd&MASK) % k; 76 while(t3[ic]!=0) ic = (ic+1) % k; 77 t3[k] = ic; 78 t3[ic] = k; 79 } 80 for(i=0;i<ROTORSZ;i++) 81 t2[t1[i]&MASK] = i; 82 } 83 84 int 85 main(int argc, char **argv) 86 { 87 int i, n1, n2, nr1, nr2; 88 int secureflg = 0, kflag = 0; 89 char *cp; 90 91 if (argc > 1 && argv[1][0] == '-') { 92 if (argv[1][1] == 's') { 93 argc--; 94 argv++; 95 secureflg = 1; 96 } else if (argv[1][1] == 'k') { 97 argc--; 98 argv++; 99 kflag = 1; 100 } 101 } 102 if (kflag) { 103 if ((cp = getenv(MINUSKVAR)) == NULL) { 104 fprintf(stderr, "%s not set\n", MINUSKVAR); 105 exit(1); 106 } 107 setup(cp); 108 } else if (argc != 2) { 109 setup(getpass("Enter key:")); 110 } 111 else 112 setup(argv[1]); 113 n1 = 0; 114 n2 = 0; 115 nr2 = 0; 116 117 while((i=getchar()) != -1) { 118 if (secureflg) { 119 nr1 = deck[n1]&MASK; 120 nr2 = deck[nr1]&MASK; 121 } else { 122 nr1 = n1; 123 } 124 i = t2[(t3[(t1[(i+nr1)&MASK]+nr2)&MASK]-nr2)&MASK]-nr1; 125 putchar(i); 126 n1++; 127 if(n1==ROTORSZ) { 128 n1 = 0; 129 n2++; 130 if(n2==ROTORSZ) n2 = 0; 131 if (secureflg) { 132 shuffle(deck); 133 } else { 134 nr2 = n2; 135 } 136 } 137 } 138 139 return 0; 140 } 141 142 static void 143 shuffle(char *deckary) 144 { 145 int i, ic, k, temp; 146 unsigned rnd; 147 static long seed = 123; 148 149 for(i=0;i<ROTORSZ;i++) { 150 seed = 5*seed + buf[i%13]; 151 rnd = seed % 65521; 152 k = ROTORSZ-1 - i; 153 ic = (rnd&MASK)%(k+1); 154 temp = deckary[k]; 155 deckary[k] = deckary[ic]; 156 deckary[ic] = temp; 157 } 158 } 159