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 <mar...@strongswan.org>
---
include/linux/xfrm.h | 1 +
include/net/xfrm.h | 1 +
net/xfrm/xfrm_user.c | 19 +++++++++++++++++--
3 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index b971e38..930fdd2 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -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)
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index bcfb6b2..bdcade7 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -143,6 +143,7 @@ struct xfrm_state {
struct xfrm_id id;
struct xfrm_selector sel;
struct xfrm_mark mark;
+ u32 tfcpad;
u32 genid;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 8bae6b2..8eb8895 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -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);
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
