141 lines
2.8 KiB
C
141 lines
2.8 KiB
C
/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
|
|
/* SPDX-License-Identifier: Unlicense */
|
|
|
|
/**
|
|
@file aesgcm.c
|
|
AES128-GCM demo - file en-&decryption, Steffen Jaeckel
|
|
Uses the format: |ciphertext|tag-16-bytes|
|
|
*/
|
|
|
|
#define _GNU_SOURCE
|
|
|
|
#include <tomcrypt.h>
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <dirent.h>
|
|
#include <string.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
|
|
#ifndef LTC_GCM_MODE
|
|
int main(void)
|
|
{
|
|
return -1;
|
|
}
|
|
#else
|
|
|
|
#include "gcm-file/gcm_filehandle.c"
|
|
#include "gcm-file/gcm_file.c"
|
|
|
|
|
|
static off_t fsize(const char *filename)
|
|
{
|
|
struct stat st;
|
|
|
|
if (stat(filename, &st) == 0) return st.st_size;
|
|
|
|
return -1;
|
|
}
|
|
|
|
#if defined(__linux__) && defined(__GLIBC_PREREQ)
|
|
#if __GLIBC_PREREQ(2, 14)
|
|
#define HAS_SYNCFS
|
|
#endif
|
|
#endif
|
|
|
|
static int mv(const char *old_name, const char *new_name)
|
|
{
|
|
int fd;
|
|
if (rename(old_name, new_name) == -1) return -1;
|
|
fd = open(new_name, 0);
|
|
if (fd == -1) return -1;
|
|
#if !defined(_WIN32)
|
|
if (fsync(fd) != 0) goto OUT;
|
|
#if defined(HAS_SYNCFS)
|
|
syncfs(fd);
|
|
#else
|
|
sync();
|
|
#endif
|
|
OUT:
|
|
#endif
|
|
close(fd);
|
|
return 0;
|
|
}
|
|
|
|
static void LTC_NORETURN die(int ret)
|
|
{
|
|
fprintf(stderr, "Usage: aesgcm <-e|-d> <infile> <outfile> <88|96 char hex-string 'IV | key'>\n");
|
|
exit(ret);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int ret = 0, err, arg, direction, res, tmp;
|
|
size_t keylen;
|
|
uint8_t keybuf[48] = {0};
|
|
char *out = NULL;
|
|
const char *mode, *in_file, *out_file, *key_string;
|
|
unsigned long ivlen, key_len;
|
|
|
|
if (argc < 5) {
|
|
if (argc > 1 && strstr(argv[1], "-h"))
|
|
die(0);
|
|
else
|
|
die(__LINE__);
|
|
}
|
|
|
|
arg = 1;
|
|
mode = argv[arg++];
|
|
in_file = argv[arg++];
|
|
out_file = argv[arg++];
|
|
key_string = argv[arg++];
|
|
|
|
if(strcmp(mode, "-d") == 0) direction = GCM_DECRYPT;
|
|
else if(strcmp(mode, "-e") == 0) direction = GCM_ENCRYPT;
|
|
else die(__LINE__);
|
|
|
|
if (fsize(in_file) <= 0) die(__LINE__);
|
|
|
|
keylen = XSTRLEN(key_string);
|
|
if (keylen != 88 && keylen != 96) die(__LINE__);
|
|
|
|
key_len = sizeof(keybuf);
|
|
if ((err = base16_decode(key_string, keylen, keybuf, &key_len)) != CRYPT_OK) {
|
|
fprintf(stderr, "boooh %s\n", error_to_string(err));
|
|
die(__LINE__);
|
|
}
|
|
|
|
register_all_ciphers();
|
|
|
|
if(asprintf(&out, "%s-XXXXXX", out_file) < 0) die(__LINE__);
|
|
if((tmp = mkstemp(out)) == -1) {
|
|
ret = __LINE__;
|
|
goto cleanup;
|
|
}
|
|
close(tmp);
|
|
ivlen = keylen/2 - 32;
|
|
if((err = gcm_file(find_cipher("aes"), &keybuf[ivlen], 32, keybuf, ivlen, NULL, 0, in_file, out, 16, direction, &res)) != CRYPT_OK) {
|
|
fprintf(stderr, "boooh %s\n", error_to_string(err));
|
|
ret = __LINE__;
|
|
goto cleanup;
|
|
}
|
|
|
|
if(res != 1) {
|
|
ret = __LINE__;
|
|
}
|
|
else
|
|
{
|
|
if (mv(out, out_file) != 0) ret = __LINE__;
|
|
}
|
|
|
|
cleanup:
|
|
if(ret != 0) unlink(out);
|
|
free(out);
|
|
|
|
|
|
return ret;
|
|
}
|
|
#endif
|