crypto: add additional query accessors for cipher instances

Adds new methods to allow querying the length of the cipher
key, block size and initialization vectors.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrange 2015-10-23 16:13:50 +01:00
parent 5dc42c186d
commit dd2bf9eb95
3 changed files with 95 additions and 0 deletions

View file

@ -28,6 +28,54 @@ static size_t alg_key_len[QCRYPTO_CIPHER_ALG_LAST] = {
[QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
};
static size_t alg_block_len[QCRYPTO_CIPHER_ALG_LAST] = {
[QCRYPTO_CIPHER_ALG_AES_128] = 16,
[QCRYPTO_CIPHER_ALG_AES_192] = 16,
[QCRYPTO_CIPHER_ALG_AES_256] = 16,
[QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
};
static bool mode_need_iv[QCRYPTO_CIPHER_MODE_LAST] = {
[QCRYPTO_CIPHER_MODE_ECB] = false,
[QCRYPTO_CIPHER_MODE_CBC] = true,
};
size_t qcrypto_cipher_get_block_len(QCryptoCipherAlgorithm alg)
{
if (alg >= G_N_ELEMENTS(alg_key_len)) {
return 0;
}
return alg_block_len[alg];
}
size_t qcrypto_cipher_get_key_len(QCryptoCipherAlgorithm alg)
{
if (alg >= G_N_ELEMENTS(alg_key_len)) {
return 0;
}
return alg_key_len[alg];
}
size_t qcrypto_cipher_get_iv_len(QCryptoCipherAlgorithm alg,
QCryptoCipherMode mode)
{
if (alg >= G_N_ELEMENTS(alg_block_len)) {
return 0;
}
if (mode >= G_N_ELEMENTS(mode_need_iv)) {
return 0;
}
if (mode_need_iv[mode]) {
return alg_block_len[alg];
}
return 0;
}
static bool
qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
size_t nkey,