[101/151] dm crypt: move private iv fields to structs

Greg KH
2009-12-17T04:24:35Z

From: Milan Broz <mbroz@redhat.com>

commit 6047359277517c4e56d8bfd6ea4966d7a3924151 upstream.

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.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/md/dm-crypt.c | 35 ++++++++++++++++++++++-------------
1 file changed, 22 insertions(+), 13 deletions(-)

--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -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 cry
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 cry
}
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 cry
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 cry

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;