1/* encrypt V1.1 Fri Oct 18 04:28:03 NZDT 2002 */
2/* File de/encryption, using libtomcrypt */
3/* Written by Daniel Richards <kyhwana@world-net.co.nz> */
4/* Help from Tom St Denis with various bits */
5/* This code is public domain, no rights reserved. */
6/* Encrypts by default, -d flag enables decryption */
7/* ie: ./encrypt blowfish story.txt story.ct */
8/* ./encrypt -d blowfish story.ct story.pt */
9
10#include <tomcrypt.h>
11
12int errno;
13
14int usage(char *name)
15{
16   int x;
17
18   printf("Usage: %s [-d](ecrypt) cipher infile outfile\nCiphers:\n", name);
19   for (x = 0; cipher_descriptor[x].name != NULL; x++) {
20      printf("%s\n",cipher_descriptor[x].name);
21   }
22   exit(1);
23}
24
25void register_algs(void)
26{
27   int x;
28
29#ifdef RIJNDAEL
30  register_cipher (&aes_desc);
31#endif
32#ifdef BLOWFISH
33  register_cipher (&blowfish_desc);
34#endif
35#ifdef XTEA
36  register_cipher (&xtea_desc);
37#endif
38#ifdef RC5
39  register_cipher (&rc5_desc);
40#endif
41#ifdef RC6
42  register_cipher (&rc6_desc);
43#endif
44#ifdef SAFERP
45  register_cipher (&saferp_desc);
46#endif
47#ifdef TWOFISH
48  register_cipher (&twofish_desc);
49#endif
50#ifdef SAFER
51  register_cipher (&safer_k64_desc);
52  register_cipher (&safer_sk64_desc);
53  register_cipher (&safer_k128_desc);
54  register_cipher (&safer_sk128_desc);
55#endif
56#ifdef RC2
57  register_cipher (&rc2_desc);
58#endif
59#ifdef DES
60  register_cipher (&des_desc);
61  register_cipher (&des3_desc);
62#endif
63#ifdef CAST5
64  register_cipher (&cast5_desc);
65#endif
66#ifdef NOEKEON
67  register_cipher (&noekeon_desc);
68#endif
69#ifdef SKIPJACK
70  register_cipher (&skipjack_desc);
71#endif
72#ifdef KHAZAD
73  register_cipher (&khazad_desc);
74#endif
75#ifdef ANUBIS
76  register_cipher (&anubis_desc);
77#endif
78
79   if (register_hash(&sha256_desc) == -1) {
80      printf("Error registering SHA256\n");
81      exit(-1);
82   }
83
84   if (register_prng(&yarrow_desc) == -1) {
85      printf("Error registering yarrow PRNG\n");
86      exit(-1);
87   }
88
89   if (register_prng(&sprng_desc) == -1) {
90      printf("Error registering sprng PRNG\n");
91      exit(-1);
92   }
93}
94
95int main(int argc, char *argv[])
96{
97   unsigned char plaintext[512],ciphertext[512];
98   unsigned char tmpkey[512], key[MAXBLOCKSIZE], IV[MAXBLOCKSIZE];
99   unsigned char inbuf[512]; /* i/o block size */
100   unsigned long outlen, y, ivsize, x, decrypt;
101   symmetric_CTR ctr;
102   int cipher_idx, hash_idx, ks;
103   char *infile, *outfile, *cipher;
104   prng_state prng;
105   FILE *fdin, *fdout;
106
107   /* register algs, so they can be printed */
108   register_algs();
109
110   if (argc < 4) {
111      return usage(argv[0]);
112   }
113
114   if (!strcmp(argv[1], "-d")) {
115      decrypt = 1;
116      cipher  = argv[2];
117      infile  = argv[3];
118      outfile = argv[4];
119   } else {
120      decrypt = 0;
121      cipher  = argv[1];
122      infile  = argv[2];
123      outfile = argv[3];
124   }
125
126   /* file handles setup */
127   fdin = fopen(infile,"rb");
128   if (fdin == NULL) {
129      perror("Can't open input for reading");
130      exit(-1);
131   }
132
133   fdout = fopen(outfile,"wb");
134   if (fdout == NULL) {
135      perror("Can't open output for writing");
136      exit(-1);
137   }
138
139   cipher_idx = find_cipher(cipher);
140   if (cipher_idx == -1) {
141      printf("Invalid cipher entered on command line.\n");
142      exit(-1);
143   }
144
145   hash_idx = find_hash("sha256");
146   if (hash_idx == -1) {
147      printf("SHA256 not found...?\n");
148      exit(-1);
149   }
150
151   ivsize = cipher_descriptor[cipher_idx].block_length;
152   ks = hash_descriptor[hash_idx].hashsize;
153   if (cipher_descriptor[cipher_idx].keysize(&ks) != CRYPT_OK) {
154      printf("Invalid keysize???\n");
155      exit(-1);
156   }
157
158   printf("\nEnter key: ");
159   fgets((char *)tmpkey,sizeof(tmpkey), stdin);
160   outlen = sizeof(key);
161   if ((errno = hash_memory(hash_idx,tmpkey,strlen((char *)tmpkey),key,&outlen)) != CRYPT_OK) {
162      printf("Error hashing key: %s\n", error_to_string(errno));
163      exit(-1);
164   }
165
166   if (decrypt) {
167      /* Need to read in IV */
168      if (fread(IV,1,ivsize,fdin) != ivsize) {
169         printf("Error reading IV from input.\n");
170         exit(-1);
171      }
172
173      if ((errno = ctr_start(cipher_idx,IV,key,ks,0,CTR_COUNTER_LITTLE_ENDIAN,&ctr)) != CRYPT_OK) {
174         printf("ctr_start error: %s\n",error_to_string(errno));
175         exit(-1);
176      }
177
178      /* IV done */
179      do {
180         y = fread(inbuf,1,sizeof(inbuf),fdin);
181
182         if ((errno = ctr_decrypt(inbuf,plaintext,y,&ctr)) != CRYPT_OK) {
183            printf("ctr_decrypt error: %s\n", error_to_string(errno));
184            exit(-1);
185         }
186
187         if (fwrite(plaintext,1,y,fdout) != y) {
188            printf("Error writing to file.\n");
189            exit(-1);
190         }
191      } while (y == sizeof(inbuf));
192      fclose(fdin);
193      fclose(fdout);
194
195   } else {  /* encrypt */
196      /* Setup yarrow for random bytes for IV */
197
198      if ((errno = rng_make_prng(128, find_prng("yarrow"), &prng, NULL)) != CRYPT_OK) {
199         printf("Error setting up PRNG, %s\n", error_to_string(errno));
200      }
201
202      /* You can use rng_get_bytes on platforms that support it */
203      /* x = rng_get_bytes(IV,ivsize,NULL);*/
204      x = yarrow_read(IV,ivsize,&prng);
205      if (x != ivsize) {
206         printf("Error reading PRNG for IV required.\n");
207         exit(-1);
208      }
209
210      if (fwrite(IV,1,ivsize,fdout) != ivsize) {
211         printf("Error writing IV to output.\n");
212         exit(-1);
213      }
214
215      if ((errno = ctr_start(cipher_idx,IV,key,ks,0,CTR_COUNTER_LITTLE_ENDIAN,&ctr)) != CRYPT_OK) {
216         printf("ctr_start error: %s\n",error_to_string(errno));
217         exit(-1);
218      }
219
220      do {
221         y = fread(inbuf,1,sizeof(inbuf),fdin);
222
223         if ((errno = ctr_encrypt(inbuf,ciphertext,y,&ctr)) != CRYPT_OK) {
224            printf("ctr_encrypt error: %s\n", error_to_string(errno));
225            exit(-1);
226         }
227
228         if (fwrite(ciphertext,1,y,fdout) != y) {
229            printf("Error writing to output.\n");
230            exit(-1);
231         }
232      } while (y == sizeof(inbuf));
233      fclose(fdout);
234      fclose(fdin);
235   }
236   return 0;
237}
238
239/* $Source: /cvs/libtom/libtomcrypt/demos/encrypt.c,v $ */
240/* $Revision: 1.3 $ */
241/* $Date: 2005/08/04 20:43:50 $ */
242