xfrm: Add Traffic Flow Confidentiality padding XFRM attribute

The XFRMA_TFCPAD attribute for XFRM state installation configures
Traffic Flow Confidentiality by padding ESP packets to a specified
length.

Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Martin Willi 2010-12-08 04:37:49 +00:00 committed by David S. Miller
parent 957fca95e3
commit 35d2856b46
3 changed files with 19 additions and 2 deletions

View File

@ -283,6 +283,7 @@ enum xfrm_attr_type_t {
XFRMA_KMADDRESS, /* struct xfrm_user_kmaddress */
XFRMA_ALG_AUTH_TRUNC, /* struct xfrm_algo_auth */
XFRMA_MARK, /* struct xfrm_mark */
XFRMA_TFCPAD, /* __u32 */
__XFRMA_MAX
#define XFRMA_MAX (__XFRMA_MAX - 1)

View File

@ -143,6 +143,7 @@ struct xfrm_state {
struct xfrm_id id;
struct xfrm_selector sel;
struct xfrm_mark mark;
u32 tfcpad;
u32 genid;

View File

@ -148,7 +148,8 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
!attrs[XFRMA_ALG_AUTH_TRUNC]) ||
attrs[XFRMA_ALG_AEAD] ||
attrs[XFRMA_ALG_CRYPT] ||
attrs[XFRMA_ALG_COMP])
attrs[XFRMA_ALG_COMP] ||
attrs[XFRMA_TFCPAD])
goto out;
break;
@ -165,6 +166,9 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
attrs[XFRMA_ALG_CRYPT]) &&
attrs[XFRMA_ALG_AEAD])
goto out;
if (attrs[XFRMA_TFCPAD] &&
p->mode != XFRM_MODE_TUNNEL)
goto out;
break;
case IPPROTO_COMP:
@ -172,7 +176,8 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
attrs[XFRMA_ALG_AEAD] ||
attrs[XFRMA_ALG_AUTH] ||
attrs[XFRMA_ALG_AUTH_TRUNC] ||
attrs[XFRMA_ALG_CRYPT])
attrs[XFRMA_ALG_CRYPT] ||
attrs[XFRMA_TFCPAD])
goto out;
break;
@ -186,6 +191,7 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
attrs[XFRMA_ALG_CRYPT] ||
attrs[XFRMA_ENCAP] ||
attrs[XFRMA_SEC_CTX] ||
attrs[XFRMA_TFCPAD] ||
!attrs[XFRMA_COADDR])
goto out;
break;
@ -439,6 +445,9 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
goto error;
}
if (attrs[XFRMA_TFCPAD])
x->tfcpad = nla_get_u32(attrs[XFRMA_TFCPAD]);
if (attrs[XFRMA_COADDR]) {
x->coaddr = kmemdup(nla_data(attrs[XFRMA_COADDR]),
sizeof(*x->coaddr), GFP_KERNEL);
@ -688,6 +697,9 @@ static int copy_to_user_state_extra(struct xfrm_state *x,
if (x->encap)
NLA_PUT(skb, XFRMA_ENCAP, sizeof(*x->encap), x->encap);
if (x->tfcpad)
NLA_PUT_U32(skb, XFRMA_TFCPAD, x->tfcpad);
if (xfrm_mark_put(skb, &x->mark))
goto nla_put_failure;
@ -2122,6 +2134,7 @@ static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
[XFRMA_MIGRATE] = { .len = sizeof(struct xfrm_user_migrate) },
[XFRMA_KMADDRESS] = { .len = sizeof(struct xfrm_user_kmaddress) },
[XFRMA_MARK] = { .len = sizeof(struct xfrm_mark) },
[XFRMA_TFCPAD] = { .type = NLA_U32 },
};
static struct xfrm_link {
@ -2301,6 +2314,8 @@ static inline size_t xfrm_sa_len(struct xfrm_state *x)
l += nla_total_size(sizeof(*x->calg));
if (x->encap)
l += nla_total_size(sizeof(*x->encap));
if (x->tfcpad)
l += nla_total_size(sizeof(x->tfcpad));
if (x->security)
l += nla_total_size(sizeof(struct xfrm_user_sec_ctx) +
x->security->ctx_len);