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Commit e889f97a authored by Milan Broz's avatar Milan Broz Committed by Mike Snitzer
Browse files

dm crypt: factor IV constructor out to separate function 



No functional change.

Signed-off-by: default avatarMilan Broz <gmazyland@gmail.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent ef43aa38

drivers/md/dm-crypt.c

+69 −61
Original line number Diff line number Diff line
@@ -2196,6 +2196,73 @@ static void crypt_dtr(struct dm_target *ti) 
	kzfree(cc);

}



static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)

{

	struct crypt_config *cc = ti->private;



	if (crypt_integrity_mode(cc))

		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));

	else

		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));



	if (crypt_integrity_hmac(cc)) {

		cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);

		if (!cc->authenc_key) {

			ti->error = "Error allocating authenc key space";

			return -ENOMEM;

		}

	}



	if (cc->iv_size)

		/* at least a 64 bit sector number should fit in our buffer */

		cc->iv_size = max(cc->iv_size,

				  (unsigned int)(sizeof(u64) / sizeof(u8)));

	else if (ivmode) {

		DMWARN("Selected cipher does not support IVs");

		ivmode = NULL;

	}



	/* Choose ivmode, see comments at iv code. */

	if (ivmode == NULL)

		cc->iv_gen_ops = NULL;

	else if (strcmp(ivmode, "plain") == 0)

		cc->iv_gen_ops = &crypt_iv_plain_ops;

	else if (strcmp(ivmode, "plain64") == 0)

		cc->iv_gen_ops = &crypt_iv_plain64_ops;

	else if (strcmp(ivmode, "essiv") == 0)

		cc->iv_gen_ops = &crypt_iv_essiv_ops;

	else if (strcmp(ivmode, "benbi") == 0)

		cc->iv_gen_ops = &crypt_iv_benbi_ops;

	else if (strcmp(ivmode, "null") == 0)

		cc->iv_gen_ops = &crypt_iv_null_ops;

	else if (strcmp(ivmode, "lmk") == 0) {

		cc->iv_gen_ops = &crypt_iv_lmk_ops;

		/*

		 * Version 2 and 3 is recognised according

		 * to length of provided multi-key string.

		 * If present (version 3), last key is used as IV seed.

		 * All keys (including IV seed) are always the same size.

		 */

		if (cc->key_size % cc->key_parts) {

			cc->key_parts++;

			cc->key_extra_size = cc->key_size / cc->key_parts;

		}

	} else if (strcmp(ivmode, "tcw") == 0) {

		cc->iv_gen_ops = &crypt_iv_tcw_ops;

		cc->key_parts += 2; /* IV + whitening */

		cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;

	} else if (strcmp(ivmode, "random") == 0) {

		cc->iv_gen_ops = &crypt_iv_random_ops;

		/* Need storage space in integrity fields. */

		cc->integrity_iv_size = cc->iv_size;

	} else {

		ti->error = "Invalid IV mode";

		return -EINVAL;

	}



	return 0;

}



static int crypt_ctr_cipher(struct dm_target *ti,

			    char *cipher_in, char *key)

{
@@ -2205,7 +2272,6 @@ static int crypt_ctr_cipher(struct dm_target *ti, 
	int ret = -EINVAL;

	char dummy;



	/* Convert to crypto api definition? */

	if (strchr(cipher_in, '(')) {

		ti->error = "Bad cipher specification";

		return -EINVAL;
@@ -2276,67 +2342,9 @@ static int crypt_ctr_cipher(struct dm_target *ti, 
	}



	/* Initialize IV */

	if (crypt_integrity_mode(cc))

		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));

	else

		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));



	if (crypt_integrity_hmac(cc)) {

		cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);

		if (!cc->authenc_key) {

			ret = -ENOMEM;

			ti->error = "Error allocating authenc key space";

			goto bad;

		}

	}



	if (cc->iv_size)

		/* at least a 64 bit sector number should fit in our buffer */

		cc->iv_size = max(cc->iv_size,

				  (unsigned int)(sizeof(u64) / sizeof(u8)));

	else if (ivmode) {

		DMWARN("Selected cipher does not support IVs");

		ivmode = NULL;

	}



	/* Choose ivmode, see comments at iv code. */

	if (ivmode == NULL)

		cc->iv_gen_ops = NULL;

	else if (strcmp(ivmode, "plain") == 0)

		cc->iv_gen_ops = &crypt_iv_plain_ops;

	else if (strcmp(ivmode, "plain64") == 0)

		cc->iv_gen_ops = &crypt_iv_plain64_ops;

	else if (strcmp(ivmode, "essiv") == 0)

		cc->iv_gen_ops = &crypt_iv_essiv_ops;

	else if (strcmp(ivmode, "benbi") == 0)

		cc->iv_gen_ops = &crypt_iv_benbi_ops;

	else if (strcmp(ivmode, "null") == 0)

		cc->iv_gen_ops = &crypt_iv_null_ops;

	else if (strcmp(ivmode, "lmk") == 0) {

		cc->iv_gen_ops = &crypt_iv_lmk_ops;

		/*

		 * Version 2 and 3 is recognised according

		 * to length of provided multi-key string.

		 * If present (version 3), last key is used as IV seed.

		 * All keys (including IV seed) are always the same size.

		 */

		if (cc->key_size % cc->key_parts) {

			cc->key_parts++;

			cc->key_extra_size = cc->key_size / cc->key_parts;

		}

	} else if (strcmp(ivmode, "tcw") == 0) {

		cc->iv_gen_ops = &crypt_iv_tcw_ops;

		cc->key_parts += 2; /* IV + whitening */

		cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;

	} else if (strcmp(ivmode, "random") == 0) {

		cc->iv_gen_ops = &crypt_iv_random_ops;

		/* Need storage space in integrity fields. */

		cc->integrity_iv_size = cc->iv_size;

	} else {

		ret = -EINVAL;

		ti->error = "Invalid IV mode";

	ret = crypt_ctr_ivmode(ti, ivmode);

	if (ret < 0)

		goto bad;

	}



	/* Initialize and set key */

	ret = crypt_set_key(cc, key);