static int hash(const char *hash_name, size_t key_size, char *key,
size_t passphrase_size, const char *passphrase)
{
struct crypt_hash *md = NULL;
size_t len;
int round, i, r = 0;
if (crypt_hash_init(&md, hash_name))
return -ENOENT;
len = crypt_hash_size(hash_name);
for(round = 0; key_size && !r; round++) {
/* hack from hashalot to avoid null bytes in key */
for(i = 0; i < round; i++)
if (crypt_hash_write(md, "A", 1))
r = 1;
if (crypt_hash_write(md, passphrase, passphrase_size))
r = 1;
if (len > key_size)
len = key_size;
if (crypt_hash_final(md, key, len))
r = 1;
key += len;
key_size -= len;
}
crypt_hash_destroy(md);
return r;
}
/*
* Test for wrong Whirlpool variant,
* Ref: http://lists.gnupg.org/pipermail/gcrypt-devel/2014-January/002889.html
*/
static void crypt_hash_test_whirlpool_bug(void)
{
struct crypt_hash *h;
char buf[2] = "\0\0", hash_out1[64], hash_out2[64];
int r;
if (crypto_backend_whirlpool_bug >= 0)
return;
crypto_backend_whirlpool_bug = 0;
if (crypt_hash_init(&h, "whirlpool"))
return;
/* One shot */
if ((r = crypt_hash_write(h, &buf[0], 2)) ||
(r = crypt_hash_final(h, hash_out1, 64))) {
crypt_hash_destroy(h);
return;
}
/* Split buf (crypt_hash_final resets hash state) */
if ((r = crypt_hash_write(h, &buf[0], 1)) ||
(r = crypt_hash_write(h, &buf[1], 1)) ||
(r = crypt_hash_final(h, hash_out2, 64))) {
crypt_hash_destroy(h);
return;
}
crypt_hash_destroy(h);
if (memcmp(hash_out1, hash_out2, 64))
crypto_backend_whirlpool_bug = 1;
}
static int verify_hash_block(const char *hash_name, int version,
char *hash, size_t hash_size,
const char *data, size_t data_size,
const char *salt, size_t salt_size)
{
struct crypt_hash *ctx = NULL;
int r;
if (crypt_hash_init(&ctx, hash_name))
return -EINVAL;
if (version == 1 && (r = crypt_hash_write(ctx, salt, salt_size)))
goto out;
if ((r = crypt_hash_write(ctx, data, data_size)))
goto out;
if (version == 0 && (r = crypt_hash_write(ctx, salt, salt_size)))
goto out;
r = crypt_hash_final(ctx, hash, hash_size);
out:
crypt_hash_destroy(ctx);
return r;
}
static int hash_buf(const char *src, char *dst, uint32_t iv,
size_t len, const char *hash_name)
{
struct crypt_hash *hd = NULL;
char *iv_char = (char *)&iv;
int r;
iv = htonl(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;
}
/*
* Calculate hash (checksum) of |LUKS2_bin|LUKS2_JSON_area| from in-memory structs.
* LUKS2 on-disk header contains uniques salt both for primary and secondary header.
* Checksum is always calculated with zeroed checksum field in binary header.
*/
static int hdr_checksum_calculate(const char *alg, struct luks2_hdr_disk *hdr_disk,
const char *json_area, size_t json_len)
{
struct crypt_hash *hd = NULL;
int hash_size, r;
hash_size = crypt_hash_size(alg);
if (hash_size <= 0 || crypt_hash_init(&hd, alg))
return -EINVAL;
/* Binary header, csum zeroed. */
r = crypt_hash_write(hd, (char*)hdr_disk, LUKS2_HDR_BIN_LEN);
/* JSON area (including unused space) */
if (!r)
r = crypt_hash_write(hd, json_area, json_len);
if (!r)
r = crypt_hash_final(hd, (char*)hdr_disk->csum, (size_t)hash_size);
crypt_hash_destroy(hd);
return r;
}
static int hash_key(const char *src, size_t src_len,
char *dst, size_t dst_len,
const char *hash_name)
{
struct crypt_hash *hd = NULL;
int r;
if (crypt_hash_init(&hd, hash_name))
return -EINVAL;
r = crypt_hash_write(hd, src, src_len);
if (!r)
r = crypt_hash_final(hd, dst, dst_len);
crypt_hash_destroy(hd);
return r;
}