[IPSEC]: Sync series - acquire insert

This introduces a feature similar to the one described in RFC 2367:
"
   ... the application needing an SA sends a PF_KEY
   SADB_ACQUIRE message down to the Key Engine, which then either
   returns an error or sends a similar SADB_ACQUIRE message up to one or
   more key management applications capable of creating such SAs.
   ...
   ...
   The third is where an application-layer consumer of security
   associations (e.g.  an OSPFv2 or RIPv2 daemon) needs a security
   association.

        Send an SADB_ACQUIRE message from a user process to the kernel.

        <base, address(SD), (address(P),) (identity(SD),) (sensitivity,)
          proposal>

        The kernel returns an SADB_ACQUIRE message to registered
          sockets.

        <base, address(SD), (address(P),) (identity(SD),) (sensitivity,)
          proposal>

        The user-level consumer waits for an SADB_UPDATE or SADB_ADD
        message for its particular type, and then can use that
        association by using SADB_GET messages.

 "
An app such as OSPF could then use ipsec KM to get keys

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 54 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index e230ba5328d3..d6e6527fd8d7 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1232,6 +1232,58 @@ static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **x
         return 0;
 }
 
+static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
+{
+        struct xfrm_policy *xp;
+        struct xfrm_user_tmpl *ut;
+        int i;
+        struct rtattr *rt = xfrma[XFRMA_TMPL-1];
+
+        struct xfrm_user_acquire *ua = NLMSG_DATA(nlh);
+        struct xfrm_state *x = xfrm_state_alloc();
+        int err = -ENOMEM;
+
+        if (!x)
+                return err;
+
+        err = verify_newpolicy_info(&ua->policy);
+        if (err) {
+                printk("BAD policy passed\n");
+                kfree(x);
+                return err;
+        }
+
+        /*   build an XP */
+        xp = xfrm_policy_construct(&ua->policy, (struct rtattr **) xfrma, &err);        if (!xp) {
+                kfree(x);
+                return err;
+        }
+
+        memcpy(&x->id, &ua->id, sizeof(ua->id));
+        memcpy(&x->props.saddr, &ua->saddr, sizeof(ua->saddr));
+        memcpy(&x->sel, &ua->sel, sizeof(ua->sel));
+
+        ut = RTA_DATA(rt);
+        /* extract the templates and for each call km_key */
+        for (i = 0; i < xp->xfrm_nr; i++, ut++) {
+                struct xfrm_tmpl *t = &xp->xfrm_vec[i];
+                memcpy(&x->id, &t->id, sizeof(x->id));
+                x->props.mode = t->mode;
+                x->props.reqid = t->reqid;
+                x->props.family = ut->family;
+                t->aalgos = ua->aalgos;
+                t->ealgos = ua->ealgos;
+                t->calgos = ua->calgos;
+                err = km_query(x, t, xp);
+
+        }
+
+        kfree(x);
+        kfree(xp);
+
+        return 0;
+}
+
 
 #define XMSGSIZE(type) NLMSG_LENGTH(sizeof(struct type))
 
@@ -1243,6 +1295,7 @@ static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
         [XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
         [XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
         [XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userspi_info),
+        [XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_acquire),
         [XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_info),
         [XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_info),
         [XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_flush),
@@ -1266,6 +1319,7 @@ static struct xfrm_link {
         [XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy,
                                                    .dump = xfrm_dump_policy   },
         [XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = { .doit = xfrm_alloc_userspi },
+        [XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = { .doit = xfrm_add_acquire   },
         [XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
         [XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
         [XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = { .doit = xfrm_flush_sa      },