return num;
}
+struct key_and_iv_params {
+ u8 master_key[MAX_KEY_SIZE];
+ int master_key_size;
+ enum kdf_algorithm kdf;
+ u8 mode_num;
+ u8 file_nonce[FILE_NONCE_SIZE];
+ bool file_nonce_specified;
+};
+
/*
* Get the key and starting IV with which the encryption will actually be done.
* If a KDF was specified, a subkey is derived from the master key and the mode
* number or file nonce. Otherwise, the master key is used directly.
*/
-static void get_key_and_iv(const u8 *master_key, size_t master_key_size,
- enum kdf_algorithm kdf,
- u8 mode_num, const u8 nonce[FILE_NONCE_SIZE],
+static void get_key_and_iv(const struct key_and_iv_params *params,
u8 *real_key, size_t real_key_size,
struct fscrypt_iv *iv)
{
- bool nonce_in_iv = false;
+ bool file_nonce_in_iv = false;
struct aes_key aes_key;
u8 info[8 + 1 + FILE_NONCE_SIZE] = "fscrypt";
size_t infolen = 8;
size_t i;
- ASSERT(real_key_size <= master_key_size);
+ ASSERT(real_key_size <= params->master_key_size);
memset(iv, 0, sizeof(*iv));
- switch (kdf) {
+ switch (params->kdf) {
case KDF_NONE:
- if (mode_num != 0)
+ if (params->mode_num != 0)
die("--mode-num isn't supported with --kdf=none");
- memcpy(real_key, master_key, real_key_size);
- nonce_in_iv = true;
+ memcpy(real_key, params->master_key, real_key_size);
+ file_nonce_in_iv = true;
break;
case KDF_AES_128_ECB:
- if (nonce == NULL)
+ if (!params->file_nonce_specified)
die("--file-nonce is required with --kdf=AES-128-ECB");
- if (mode_num != 0)
+ if (params->mode_num != 0)
die("--mode-num isn't supported with --kdf=AES-128-ECB");
STATIC_ASSERT(FILE_NONCE_SIZE == AES_128_KEY_SIZE);
ASSERT(real_key_size % AES_BLOCK_SIZE == 0);
- aes_setkey(&aes_key, nonce, AES_128_KEY_SIZE);
+ aes_setkey(&aes_key, params->file_nonce, AES_128_KEY_SIZE);
for (i = 0; i < real_key_size; i += AES_BLOCK_SIZE)
- aes_encrypt(&aes_key, &master_key[i], &real_key[i]);
+ aes_encrypt(&aes_key, ¶ms->master_key[i],
+ &real_key[i]);
break;
case KDF_HKDF_SHA512:
- if (mode_num != 0) {
+ if (params->mode_num != 0) {
info[infolen++] = 3; /* HKDF_CONTEXT_PER_MODE_KEY */
- info[infolen++] = mode_num;
- nonce_in_iv = true;
- } else if (nonce != NULL) {
+ info[infolen++] = params->mode_num;
+ file_nonce_in_iv = true;
+ } else if (params->file_nonce_specified) {
info[infolen++] = 2; /* HKDF_CONTEXT_PER_FILE_KEY */
- memcpy(&info[infolen], nonce, FILE_NONCE_SIZE);
+ memcpy(&info[infolen], params->file_nonce,
+ FILE_NONCE_SIZE);
infolen += FILE_NONCE_SIZE;
} else {
die("With --kdf=HKDF-SHA512, at least one of --file-nonce and --mode-num must be specified");
}
- hkdf_sha512(master_key, master_key_size, NULL, 0,
- info, infolen, real_key, real_key_size);
+ hkdf_sha512(params->master_key, params->master_key_size,
+ NULL, 0, info, infolen, real_key, real_key_size);
break;
default:
ASSERT(0);
}
- if (nonce_in_iv && nonce != NULL)
- memcpy(&iv->bytes[8], nonce, FILE_NONCE_SIZE);
+ if (file_nonce_in_iv && params->file_nonce_specified)
+ memcpy(&iv->bytes[8], params->file_nonce, FILE_NONCE_SIZE);
}
enum {
{
size_t block_size = 4096;
bool decrypting = false;
- u8 _file_nonce[FILE_NONCE_SIZE];
- u8 *file_nonce = NULL;
- enum kdf_algorithm kdf = KDF_NONE;
- u8 mode_num = 0;
+ struct key_and_iv_params params;
size_t padding = 0;
const struct fscrypt_cipher *cipher;
- u8 master_key[MAX_KEY_SIZE];
- int master_key_size;
u8 real_key[MAX_KEY_SIZE];
struct fscrypt_iv iv;
char *tmp;
int c;
+ memset(¶ms, 0, sizeof(params));
+
aes_init();
#ifdef ENABLE_ALG_TESTS
decrypting = true;
break;
case OPT_FILE_NONCE:
- if (hex2bin(optarg, _file_nonce, FILE_NONCE_SIZE) !=
- FILE_NONCE_SIZE)
+ if (hex2bin(optarg, params.file_nonce, FILE_NONCE_SIZE)
+ != FILE_NONCE_SIZE)
die("Invalid file nonce: %s", optarg);
- file_nonce = _file_nonce;
+ params.file_nonce_specified = true;
break;
case OPT_HELP:
usage(stdout);
return 0;
case OPT_KDF:
- kdf = parse_kdf_algorithm(optarg);
+ params.kdf = parse_kdf_algorithm(optarg);
break;
case OPT_MODE_NUM:
- mode_num = parse_mode_number(optarg);
+ params.mode_num = parse_mode_number(optarg);
break;
case OPT_PADDING:
padding = strtoul(optarg, &tmp, 10);
die("Block size of %zu bytes is too small for cipher %s",
block_size, cipher->name);
- master_key_size = hex2bin(argv[1], master_key, MAX_KEY_SIZE);
- if (master_key_size < 0)
+ params.master_key_size = hex2bin(argv[1], params.master_key,
+ MAX_KEY_SIZE);
+ if (params.master_key_size < 0)
die("Invalid master_key: %s", argv[1]);
- if (master_key_size < cipher->keysize)
+ if (params.master_key_size < cipher->keysize)
die("Master key is too short for cipher %s", cipher->name);
- get_key_and_iv(master_key, master_key_size, kdf, mode_num, file_nonce,
- real_key, cipher->keysize, &iv);
+ get_key_and_iv(¶ms, real_key, cipher->keysize, &iv);
crypt_loop(cipher, real_key, &iv, decrypting, block_size, padding);
return 0;
projects / xfstests-dev.git / blobdiff