xfrm: Store aalg in xfrm_state with a user specified truncation length
Adding a xfrm_state requires an authentication algorithm specified
either as xfrm_algo or as xfrm_algo_auth with a specific truncation
length. For compatibility, both attributes are dumped to userspace,
and we also accept both attributes, but prefer the new syntax.
If no truncation length is specified, or the authentication algorithm
is specified using xfrm_algo, the truncation length from the algorithm
description in the kernel is used.
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 93d184b..6d85861 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -162,7 +162,7 @@
struct xfrm_lifetime_cfg lft;
/* Data for transformer */
- struct xfrm_algo *aalg;
+ struct xfrm_algo_auth *aalg;
struct xfrm_algo *ealg;
struct xfrm_algo *calg;
struct xfrm_algo_aead *aead;
@@ -1532,12 +1532,22 @@
return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
}
+static inline int xfrm_alg_auth_len(struct xfrm_algo_auth *alg)
+{
+ return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
+}
+
#ifdef CONFIG_XFRM_MIGRATE
static inline struct xfrm_algo *xfrm_algo_clone(struct xfrm_algo *orig)
{
return kmemdup(orig, xfrm_alg_len(orig), GFP_KERNEL);
}
+static inline struct xfrm_algo_auth *xfrm_algo_auth_clone(struct xfrm_algo_auth *orig)
+{
+ return kmemdup(orig, xfrm_alg_auth_len(orig), GFP_KERNEL);
+}
+
static inline void xfrm_states_put(struct xfrm_state **states, int n)
{
int i;
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index e9ac0ce..d847f1a 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1114,7 +1114,7 @@
x->props.saddr = orig->props.saddr;
if (orig->aalg) {
- x->aalg = xfrm_algo_clone(orig->aalg);
+ x->aalg = xfrm_algo_auth_clone(orig->aalg);
if (!x->aalg)
goto error;
}
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index b95a2d6..fb42d77 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -62,6 +62,22 @@
return 0;
}
+static int verify_auth_trunc(struct nlattr **attrs)
+{
+ struct nlattr *rt = attrs[XFRMA_ALG_AUTH_TRUNC];
+ struct xfrm_algo_auth *algp;
+
+ if (!rt)
+ return 0;
+
+ algp = nla_data(rt);
+ if (nla_len(rt) < xfrm_alg_auth_len(algp))
+ return -EINVAL;
+
+ algp->alg_name[CRYPTO_MAX_ALG_NAME - 1] = '\0';
+ return 0;
+}
+
static int verify_aead(struct nlattr **attrs)
{
struct nlattr *rt = attrs[XFRMA_ALG_AEAD];
@@ -128,7 +144,8 @@
err = -EINVAL;
switch (p->id.proto) {
case IPPROTO_AH:
- if (!attrs[XFRMA_ALG_AUTH] ||
+ if ((!attrs[XFRMA_ALG_AUTH] &&
+ !attrs[XFRMA_ALG_AUTH_TRUNC]) ||
attrs[XFRMA_ALG_AEAD] ||
attrs[XFRMA_ALG_CRYPT] ||
attrs[XFRMA_ALG_COMP])
@@ -139,10 +156,12 @@
if (attrs[XFRMA_ALG_COMP])
goto out;
if (!attrs[XFRMA_ALG_AUTH] &&
+ !attrs[XFRMA_ALG_AUTH_TRUNC] &&
!attrs[XFRMA_ALG_CRYPT] &&
!attrs[XFRMA_ALG_AEAD])
goto out;
if ((attrs[XFRMA_ALG_AUTH] ||
+ attrs[XFRMA_ALG_AUTH_TRUNC] ||
attrs[XFRMA_ALG_CRYPT]) &&
attrs[XFRMA_ALG_AEAD])
goto out;
@@ -152,6 +171,7 @@
if (!attrs[XFRMA_ALG_COMP] ||
attrs[XFRMA_ALG_AEAD] ||
attrs[XFRMA_ALG_AUTH] ||
+ attrs[XFRMA_ALG_AUTH_TRUNC] ||
attrs[XFRMA_ALG_CRYPT])
goto out;
break;
@@ -161,6 +181,7 @@
case IPPROTO_ROUTING:
if (attrs[XFRMA_ALG_COMP] ||
attrs[XFRMA_ALG_AUTH] ||
+ attrs[XFRMA_ALG_AUTH_TRUNC] ||
attrs[XFRMA_ALG_AEAD] ||
attrs[XFRMA_ALG_CRYPT] ||
attrs[XFRMA_ENCAP] ||
@@ -176,6 +197,8 @@
if ((err = verify_aead(attrs)))
goto out;
+ if ((err = verify_auth_trunc(attrs)))
+ goto out;
if ((err = verify_one_alg(attrs, XFRMA_ALG_AUTH)))
goto out;
if ((err = verify_one_alg(attrs, XFRMA_ALG_CRYPT)))
@@ -229,6 +252,66 @@
return 0;
}
+static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
+ struct nlattr *rta)
+{
+ struct xfrm_algo *ualg;
+ struct xfrm_algo_auth *p;
+ struct xfrm_algo_desc *algo;
+
+ if (!rta)
+ return 0;
+
+ ualg = nla_data(rta);
+
+ algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
+ if (!algo)
+ return -ENOSYS;
+ *props = algo->desc.sadb_alg_id;
+
+ p = kmalloc(sizeof(*p) + (ualg->alg_key_len + 7) / 8, GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ strcpy(p->alg_name, algo->name);
+ p->alg_key_len = ualg->alg_key_len;
+ p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;
+ memcpy(p->alg_key, ualg->alg_key, (ualg->alg_key_len + 7) / 8);
+
+ *algpp = p;
+ return 0;
+}
+
+static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
+ struct nlattr *rta)
+{
+ struct xfrm_algo_auth *p, *ualg;
+ struct xfrm_algo_desc *algo;
+
+ if (!rta)
+ return 0;
+
+ ualg = nla_data(rta);
+
+ algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
+ if (!algo)
+ return -ENOSYS;
+ if (ualg->alg_trunc_len > algo->uinfo.auth.icv_fullbits)
+ return -EINVAL;
+ *props = algo->desc.sadb_alg_id;
+
+ p = kmemdup(ualg, xfrm_alg_auth_len(ualg), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ strcpy(p->alg_name, algo->name);
+ if (!p->alg_trunc_len)
+ p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;
+
+ *algpp = p;
+ return 0;
+}
+
static int attach_aead(struct xfrm_algo_aead **algpp, u8 *props,
struct nlattr *rta)
{
@@ -332,10 +415,14 @@
if ((err = attach_aead(&x->aead, &x->props.ealgo,
attrs[XFRMA_ALG_AEAD])))
goto error;
- if ((err = attach_one_algo(&x->aalg, &x->props.aalgo,
- xfrm_aalg_get_byname,
- attrs[XFRMA_ALG_AUTH])))
+ if ((err = attach_auth_trunc(&x->aalg, &x->props.aalgo,
+ attrs[XFRMA_ALG_AUTH_TRUNC])))
goto error;
+ if (!x->props.aalgo) {
+ if ((err = attach_auth(&x->aalg, &x->props.aalgo,
+ attrs[XFRMA_ALG_AUTH])))
+ goto error;
+ }
if ((err = attach_one_algo(&x->ealg, &x->props.ealgo,
xfrm_ealg_get_byname,
attrs[XFRMA_ALG_CRYPT])))
@@ -548,6 +635,24 @@
return 0;
}
+static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff *skb)
+{
+ struct xfrm_algo *algo;
+ struct nlattr *nla;
+
+ nla = nla_reserve(skb, XFRMA_ALG_AUTH,
+ sizeof(*algo) + (auth->alg_key_len + 7) / 8);
+ if (!nla)
+ return -EMSGSIZE;
+
+ algo = nla_data(nla);
+ strcpy(algo->alg_name, auth->alg_name);
+ memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8);
+ algo->alg_key_len = auth->alg_key_len;
+
+ return 0;
+}
+
/* Don't change this without updating xfrm_sa_len! */
static int copy_to_user_state_extra(struct xfrm_state *x,
struct xfrm_usersa_info *p,
@@ -563,8 +668,13 @@
if (x->aead)
NLA_PUT(skb, XFRMA_ALG_AEAD, aead_len(x->aead), x->aead);
- if (x->aalg)
- NLA_PUT(skb, XFRMA_ALG_AUTH, xfrm_alg_len(x->aalg), x->aalg);
+ if (x->aalg) {
+ if (copy_to_user_auth(x->aalg, skb))
+ goto nla_put_failure;
+
+ NLA_PUT(skb, XFRMA_ALG_AUTH_TRUNC,
+ xfrm_alg_auth_len(x->aalg), x->aalg);
+ }
if (x->ealg)
NLA_PUT(skb, XFRMA_ALG_CRYPT, xfrm_alg_len(x->ealg), x->ealg);
if (x->calg)
@@ -2117,8 +2227,11 @@
size_t l = 0;
if (x->aead)
l += nla_total_size(aead_len(x->aead));
- if (x->aalg)
- l += nla_total_size(xfrm_alg_len(x->aalg));
+ if (x->aalg) {
+ l += nla_total_size(sizeof(struct xfrm_algo) +
+ (x->aalg->alg_key_len + 7) / 8);
+ l += nla_total_size(xfrm_alg_auth_len(x->aalg));
+ }
if (x->ealg)
l += nla_total_size(xfrm_alg_len(x->ealg));
if (x->calg)