/*
* AFsplitter - Anti forensic information splitter
- * Copyright 2004, Clemens Fruhwirth <clemens@endorphin.org>
- * Copyright (C) 2009 Red Hat, Inc. All rights reserved.
+ *
+ * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2020 Red Hat, Inc. All rights reserved.
*
* AFsplitter diffuses information over a large stripe of data,
- * therefor supporting secure data destruction.
+ * therefore supporting secure data destruction.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
-#include <netinet/in.h>
#include <errno.h>
-#include <gcrypt.h>
#include "internal.h"
+#include "af.h"
-static void XORblock(char const *src1, char const *src2, char *dst, size_t n)
+static void XORblock(const char *src1, const char *src2, char *dst, size_t n)
{
size_t j;
- for(j = 0; j < n; ++j)
+ for (j = 0; j < n; j++)
dst[j] = src1[j] ^ src2[j];
}
-static int hash_buf(char *src, char *dst, uint32_t iv, int len, int hash_id)
+static int hash_buf(const char *src, char *dst, uint32_t iv,
+ size_t len, const char *hash_name)
{
- gcry_md_hd_t hd;
- unsigned char *digest;
-
- iv = htonl(iv);
- if (gcry_md_open(&hd, hash_id, 0))
- return 1;
- gcry_md_write(hd, (unsigned char *)&iv, sizeof(iv));
- gcry_md_write(hd, src, len);
- digest = gcry_md_read(hd, hash_id);
- memcpy(dst, digest, len);
- gcry_md_close(hd);
- return 0;
+ struct crypt_hash *hd = NULL;
+ char *iv_char = (char *)&iv;
+ int r;
+
+ iv = be32_to_cpu(iv);
+ if (crypt_hash_init(&hd, hash_name))
+ return -EINVAL;
+
+ if ((r = crypt_hash_write(hd, iv_char, sizeof(uint32_t))))
+ goto out;
+
+ if ((r = crypt_hash_write(hd, src, len)))
+ goto out;
+
+ r = crypt_hash_final(hd, dst, len);
+out:
+ crypt_hash_destroy(hd);
+ return r;
}
-/* diffuse: Information spreading over the whole dataset with
+/*
+ * diffuse: Information spreading over the whole dataset with
* the help of hash function.
*/
-
-static int diffuse(char *src, char *dst, size_t size, int hash_id)
+static int diffuse(char *src, char *dst, size_t size, const char *hash_name)
{
- unsigned int digest_size = gcry_md_get_algo_dlen(hash_id);
+ int r, hash_size = crypt_hash_size(hash_name);
+ unsigned int digest_size;
unsigned int i, blocks, padding;
+ if (hash_size <= 0)
+ return -EINVAL;
+ digest_size = hash_size;
+
blocks = size / digest_size;
padding = size % digest_size;
- for (i = 0; i < blocks; i++)
- if(hash_buf(src + digest_size * i,
+ for (i = 0; i < blocks; i++) {
+ r = hash_buf(src + digest_size * i,
dst + digest_size * i,
- i, digest_size, hash_id))
- return 1;
+ i, (size_t)digest_size, hash_name);
+ if (r < 0)
+ return r;
+ }
- if(padding)
- if(hash_buf(src + digest_size * i,
+ if (padding) {
+ r = hash_buf(src + digest_size * i,
dst + digest_size * i,
- i, padding, hash_id))
- return 1;
+ i, (size_t)padding, hash_name);
+ if (r < 0)
+ return r;
+ }
return 0;
}
* blocknumbers. The same blocksize and blocknumbers values
* must be supplied to AF_merge to recover information.
*/
-
-int AF_split(char *src, char *dst, size_t blocksize, unsigned int blocknumbers, const char *hash)
+int AF_split(struct crypt_device *ctx, const char *src, char *dst,
+ size_t blocksize, unsigned int blocknumbers, const char *hash)
{
unsigned int i;
char *bufblock;
- int r = -EINVAL;
- int hash_id;
-
- if (!(hash_id = gcry_md_map_name(hash)))
- return -EINVAL;
+ int r;
- if((bufblock = calloc(blocksize, 1)) == NULL) return -ENOMEM;
+ bufblock = crypt_safe_alloc(blocksize);
+ if (!bufblock)
+ return -ENOMEM;
/* process everything except the last block */
- for(i=0; i<blocknumbers-1; i++) {
- r = crypt_random_get(NULL, dst+(blocksize*i), blocksize, CRYPT_RND_NORMAL);
- if(r < 0) goto out;
+ for (i = 0; i < blocknumbers - 1; i++) {
+ r = crypt_random_get(ctx, dst + blocksize * i, blocksize, CRYPT_RND_NORMAL);
+ if (r < 0)
+ goto out;
- XORblock(dst+(blocksize*i),bufblock,bufblock,blocksize);
- if(diffuse(bufblock, bufblock, blocksize, hash_id))
+ XORblock(dst + blocksize * i, bufblock, bufblock, blocksize);
+ r = diffuse(bufblock, bufblock, blocksize, hash);
+ if (r < 0)
goto out;
}
/* the last block is computed */
- XORblock(src,bufblock,dst+(i*blocksize),blocksize);
+ XORblock(src, bufblock, dst + blocksize * i, blocksize);
r = 0;
out:
- free(bufblock);
+ crypt_safe_free(bufblock);
return r;
}
-int AF_merge(char *src, char *dst, size_t blocksize, unsigned int blocknumbers, const char *hash)
+int AF_merge(struct crypt_device *ctx __attribute__((unused)), const char *src, char *dst,
+ size_t blocksize, unsigned int blocknumbers, const char *hash)
{
unsigned int i;
char *bufblock;
- int r = -EINVAL;
- int hash_id;
-
- if (!(hash_id = gcry_md_map_name(hash)))
- return -EINVAL;
+ int r;
- if((bufblock = calloc(blocksize, 1)) == NULL)
+ bufblock = crypt_safe_alloc(blocksize);
+ if (!bufblock)
return -ENOMEM;
- memset(bufblock,0,blocksize);
- for(i=0; i<blocknumbers-1; i++) {
- XORblock(src+(blocksize*i),bufblock,bufblock,blocksize);
- if(diffuse(bufblock, bufblock, blocksize, hash_id))
+ for(i = 0; i < blocknumbers - 1; i++) {
+ XORblock(src + blocksize * i, bufblock, bufblock, blocksize);
+ r = diffuse(bufblock, bufblock, blocksize, hash);
+ if (r < 0)
goto out;
}
XORblock(src + blocksize * i, bufblock, dst, blocksize);
r = 0;
out:
- free(bufblock);
+ crypt_safe_free(bufblock);
return r;
}
+
+/* Size of final split data including sector alignment */
+size_t AF_split_sectors(size_t blocksize, unsigned int blocknumbers)
+{
+ size_t af_size;
+
+ /* data material * stripes */
+ af_size = blocksize * blocknumbers;
+
+ /* round up to sector */
+ af_size = (af_size + (SECTOR_SIZE - 1)) / SECTOR_SIZE;
+
+ return af_size;
+}
projects / platform / upstream / cryptsetup.git / blobdiff