Commit 60473592 authored by Milan Broz's avatar Milan Broz Committed by Alasdair G Kergon
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dm crypt: move private iv fields to structs 



Define private structures for IV so it's easy to add further attributes
in a following patch which fixes the way key material is wiped from
memory.  Also move ESSIV destructor and remove unnecessary 'status'
operation.

There are no functional changes in this patch.

Cc: stable@kernel.org
Signed-off-by: default avatarMilan Broz <mbroz@redhat.com>
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
parent 0b430958

drivers/md/dm-crypt.c

+22 −13
Original line number Diff line number Diff line
@@ -71,10 +71,17 @@ struct crypt_iv_operations { 
	int (*ctr)(struct crypt_config *cc, struct dm_target *ti,

		   const char *opts);

	void (*dtr)(struct crypt_config *cc);

	const char *(*status)(struct crypt_config *cc);

	int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector);

};



struct iv_essiv_private {

	struct crypto_cipher *tfm;

};



struct iv_benbi_private {

	int shift;

};



/*

 * Crypt: maps a linear range of a block device

 * and encrypts / decrypts at the same time.
@@ -102,8 +109,8 @@ struct crypt_config { 
	struct crypt_iv_operations *iv_gen_ops;

	char *iv_mode;

	union {

		struct crypto_cipher *essiv_tfm;

		int benbi_shift;

		struct iv_essiv_private essiv;

		struct iv_benbi_private benbi;

	} iv_gen_private;

	sector_t iv_offset;

	unsigned int iv_size;
@@ -169,6 +176,14 @@ static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) 
	return 0;

}



static void crypt_iv_essiv_dtr(struct crypt_config *cc)

{

	struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;



	crypto_free_cipher(essiv->tfm);

	essiv->tfm = NULL;

}



static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,

			      const char *opts)

{
@@ -236,21 +251,15 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, 
	}

	kfree(salt);



	cc->iv_gen_private.essiv_tfm = essiv_tfm;

	cc->iv_gen_private.essiv.tfm = essiv_tfm;

	return 0;

}



static void crypt_iv_essiv_dtr(struct crypt_config *cc)

{

	crypto_free_cipher(cc->iv_gen_private.essiv_tfm);

	cc->iv_gen_private.essiv_tfm = NULL;

}



static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)

{

	memset(iv, 0, cc->iv_size);

	*(u64 *)iv = cpu_to_le64(sector);

	crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv);

	crypto_cipher_encrypt_one(cc->iv_gen_private.essiv.tfm, iv, iv);

	return 0;

}
@@ -273,7 +282,7 @@ static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 
		return -EINVAL;

	}



	cc->iv_gen_private.benbi_shift = 9 - log;

	cc->iv_gen_private.benbi.shift = 9 - log;



	return 0;

}
@@ -288,7 +297,7 @@ static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) 


	memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */



	val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1);

	val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi.shift) + 1);

	put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));



	return 0;