[PPP_MPPE]: Don't put InterimKey on the stack

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michal Schmidt 2007-09-25 23:05:39 -07:00 committed by David S. Miller
parent 6f4c618ddb
commit 45dfd5b5dd
1 changed files with 6 additions and 8 deletions

View File

@ -136,7 +136,7 @@ struct ppp_mppe_state {
* Key Derivation, from RFC 3078, RFC 3079.
* Equivalent to Get_Key() for MS-CHAP as described in RFC 3079.
*/
static void get_new_key_from_sha(struct ppp_mppe_state * state, unsigned char *InterimKey)
static void get_new_key_from_sha(struct ppp_mppe_state * state)
{
struct hash_desc desc;
struct scatterlist sg[4];
@ -153,8 +153,6 @@ static void get_new_key_from_sha(struct ppp_mppe_state * state, unsigned char *I
desc.flags = 0;
crypto_hash_digest(&desc, sg, nbytes, state->sha1_digest);
memcpy(InterimKey, state->sha1_digest, state->keylen);
}
/*
@ -163,21 +161,21 @@ static void get_new_key_from_sha(struct ppp_mppe_state * state, unsigned char *I
*/
static void mppe_rekey(struct ppp_mppe_state * state, int initial_key)
{
unsigned char InterimKey[MPPE_MAX_KEY_LEN];
struct scatterlist sg_in[1], sg_out[1];
struct blkcipher_desc desc = { .tfm = state->arc4 };
get_new_key_from_sha(state, InterimKey);
get_new_key_from_sha(state);
if (!initial_key) {
crypto_blkcipher_setkey(state->arc4, InterimKey, state->keylen);
setup_sg(sg_in, InterimKey, state->keylen);
crypto_blkcipher_setkey(state->arc4, state->sha1_digest,
state->keylen);
setup_sg(sg_in, state->sha1_digest, state->keylen);
setup_sg(sg_out, state->session_key, state->keylen);
if (crypto_blkcipher_encrypt(&desc, sg_out, sg_in,
state->keylen) != 0) {
printk(KERN_WARNING "mppe_rekey: cipher_encrypt failed\n");
}
} else {
memcpy(state->session_key, InterimKey, state->keylen);
memcpy(state->session_key, state->sha1_digest, state->keylen);
}
if (state->keylen == 8) {
/* See RFC 3078 */