[XFRM] STATE: Search by address using source address list.

This is a support to search transformation states by its addresses
by using source address list for Mobile IPv6 usage.
To use it from user-space, it is also added a message type for
source address as a xfrm state option.
Based on MIPL2 kernel patch.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 53 insertions, 6 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 41f3d51ffc33..b5f8ab71aa54 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -87,6 +87,22 @@ static int verify_encap_tmpl(struct rtattr **xfrma)
         return 0;
 }
 
+static int verify_one_addr(struct rtattr **xfrma, enum xfrm_attr_type_t type,
+                           xfrm_address_t **addrp)
+{
+        struct rtattr *rt = xfrma[type - 1];
+
+        if (!rt)
+                return 0;
+
+        if ((rt->rta_len - sizeof(*rt)) < sizeof(**addrp))
+                return -EINVAL;
+
+        if (addrp)
+                *addrp = RTA_DATA(rt);
+
+        return 0;
+}
 
 static inline int verify_sec_ctx_len(struct rtattr **xfrma)
 {
@@ -418,16 +434,48 @@ out:
         return err;
 }
 
+static struct xfrm_state *xfrm_user_state_lookup(struct xfrm_usersa_id *p,
+                                                 struct rtattr **xfrma,
+                                                 int *errp)
+{
+        struct xfrm_state *x = NULL;
+        int err;
+
+        if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY)) {
+                err = -ESRCH;
+                x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
+        } else {
+                xfrm_address_t *saddr = NULL;
+
+                err = verify_one_addr(xfrma, XFRMA_SRCADDR, &saddr);
+                if (err)
+                        goto out;
+
+                if (!saddr) {
+                        err = -EINVAL;
+                        goto out;
+                }
+
+                x = xfrm_state_lookup_byaddr(&p->daddr, saddr, p->proto,
+                                             p->family);
+        }
+
+ out:
+        if (!x && errp)
+                *errp = err;
+        return x;
+}
+
 static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 {
         struct xfrm_state *x;
-        int err;
+        int err = -ESRCH;
         struct km_event c;
         struct xfrm_usersa_id *p = NLMSG_DATA(nlh);
 
-        x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
+        x = xfrm_user_state_lookup(p, (struct rtattr **)xfrma, &err);
         if (x == NULL)
-                return -ESRCH;
+                return err;
 
         if ((err = security_xfrm_state_delete(x)) != 0)
                 goto out;
@@ -578,10 +626,9 @@ static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
         struct xfrm_usersa_id *p = NLMSG_DATA(nlh);
         struct xfrm_state *x;
         struct sk_buff *resp_skb;
-        int err;
+        int err = -ESRCH;
 
-        x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
-        err = -ESRCH;
+        x = xfrm_user_state_lookup(p, (struct rtattr **)xfrma, &err);
         if (x == NULL)
                 goto out_noput;