t8-mod/deps/libtomcrypt/demos/ltcrypt.c
2024-02-15 15:46:47 -05:00

196 lines
5.4 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* encrypt V1.1 Fri Oct 18 04:28:03 NZDT 2002 */
/* File de/encryption, using libtomcrypt */
/* Written by Daniel Richards <kyhwana@world-net.co.nz> */
/* Help from Tom St Denis with various bits */
/* This code is public domain, no rights reserved. */
/* Encrypts by default, -d flag enables decryption */
/* ie: ./encrypt blowfish story.txt story.ct */
/* ./encrypt -d blowfish story.ct story.pt */
#include <tomcrypt.h>
static int LTC_NORETURN usage(char *name)
{
int x;
printf("Usage encrypt: %s cipher infile outfile\n", name);
printf("Usage decrypt: %s -d cipher infile outfile\n", name);
printf("Usage test: %s -t cipher\nCiphers:\n", name);
for (x = 0; cipher_descriptor[x].name != NULL; x++) {
printf("%s\n",cipher_descriptor[x].name);
}
exit(1);
}
int main(int argc, char *argv[])
{
unsigned char plaintext[512],ciphertext[512];
unsigned char tmpkey[512], key[MAXBLOCKSIZE], IV[MAXBLOCKSIZE];
unsigned char inbuf[512]; /* i/o block size */
unsigned long outlen, y, ivsize, x, decrypt;
symmetric_CTR ctr;
int cipher_idx, hash_idx, ks;
char *infile, *outfile, *cipher;
prng_state prng;
FILE *fdin, *fdout;
int err;
/* register algs, so they can be printed */
register_all_ciphers();
register_all_hashes();
register_all_prngs();
if (argc < 4) {
if ((argc > 2) && (!strcmp(argv[1], "-t"))) {
cipher = argv[2];
cipher_idx = find_cipher(cipher);
if (cipher_idx == -1) {
printf("Invalid cipher %s entered on command line.\n", cipher);
exit(-1);
} /* if */
if (cipher_descriptor[cipher_idx].test)
{
if (cipher_descriptor[cipher_idx].test() != CRYPT_OK)
{
printf("Error when testing cipher %s.\n", cipher);
exit(-1);
}
else
{
printf("Testing cipher %s succeeded.\n", cipher);
exit(0);
} /* if ... else */
} /* if */
}
return usage(argv[0]);
}
if (!strcmp(argv[1], "-d")) {
decrypt = 1;
cipher = argv[2];
infile = argv[3];
outfile = argv[4];
} else {
decrypt = 0;
cipher = argv[1];
infile = argv[2];
outfile = argv[3];
}
/* file handles setup */
fdin = fopen(infile,"rb");
if (fdin == NULL) {
perror("Can't open input for reading");
exit(-1);
}
fdout = fopen(outfile,"wb");
if (fdout == NULL) {
perror("Can't open output for writing");
exit(-1);
}
cipher_idx = find_cipher(cipher);
if (cipher_idx == -1) {
printf("Invalid cipher entered on command line.\n");
exit(-1);
}
hash_idx = find_hash("sha256");
if (hash_idx == -1) {
printf("LTC_SHA256 not found...?\n");
exit(-1);
}
ivsize = cipher_descriptor[cipher_idx].block_length;
ks = hash_descriptor[hash_idx].hashsize;
if (cipher_descriptor[cipher_idx].keysize(&ks) != CRYPT_OK) {
printf("Invalid keysize???\n");
exit(-1);
}
printf("\nEnter key: ");
if(fgets((char *)tmpkey,sizeof(tmpkey), stdin) == NULL)
exit(-1);
outlen = sizeof(key);
if ((err = hash_memory(hash_idx,tmpkey,XSTRLEN((char *)tmpkey),key,&outlen)) != CRYPT_OK) {
printf("Error hashing key: %s\n", error_to_string(err));
exit(-1);
}
if (decrypt) {
/* Need to read in IV */
if (fread(IV,1,ivsize,fdin) != ivsize) {
printf("Error reading IV from input.\n");
exit(-1);
}
if ((err = ctr_start(cipher_idx,IV,key,ks,0,CTR_COUNTER_LITTLE_ENDIAN,&ctr)) != CRYPT_OK) {
printf("ctr_start error: %s\n",error_to_string(err));
exit(-1);
}
/* IV done */
do {
y = fread(inbuf,1,sizeof(inbuf),fdin);
if ((err = ctr_decrypt(inbuf,plaintext,y,&ctr)) != CRYPT_OK) {
printf("ctr_decrypt error: %s\n", error_to_string(err));
exit(-1);
}
if (fwrite(plaintext,1,y,fdout) != y) {
printf("Error writing to file.\n");
exit(-1);
}
} while (y == sizeof(inbuf));
fclose(fdin);
fclose(fdout);
} else { /* encrypt */
/* Setup yarrow for random bytes for IV */
if ((err = rng_make_prng(128, find_prng("yarrow"), &prng, NULL)) != CRYPT_OK) {
printf("Error setting up PRNG, %s\n", error_to_string(err));
}
/* You can use rng_get_bytes on platforms that support it */
/* x = rng_get_bytes(IV,ivsize,NULL);*/
x = yarrow_read(IV,ivsize,&prng);
if (x != ivsize) {
printf("Error reading PRNG for IV required.\n");
exit(-1);
}
if (fwrite(IV,1,ivsize,fdout) != ivsize) {
printf("Error writing IV to output.\n");
exit(-1);
}
if ((err = ctr_start(cipher_idx,IV,key,ks,0,CTR_COUNTER_LITTLE_ENDIAN,&ctr)) != CRYPT_OK) {
printf("ctr_start error: %s\n",error_to_string(err));
exit(-1);
}
do {
y = fread(inbuf,1,sizeof(inbuf),fdin);
if ((err = ctr_encrypt(inbuf,ciphertext,y,&ctr)) != CRYPT_OK) {
printf("ctr_encrypt error: %s\n", error_to_string(err));
exit(-1);
}
if (fwrite(ciphertext,1,y,fdout) != y) {
printf("Error writing to output.\n");
exit(-1);
}
} while (y == sizeof(inbuf));
fclose(fdout);
fclose(fdin);
}
return 0;
}