{pktgen, xfrm} Introduce xfrm_state_lookup_byspi for pktgen

Introduce xfrm_state_lookup_byspi to find user specified by custom
from "pgset spi xxx". Using this scheme, any flow regardless its
saddr/daddr could be transform by SA specified with configurable
spi.

Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

2 files changed, 37 insertions, 7 deletions

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 628f7c572c6e..b553c36ea0ca 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2247,13 +2247,21 @@ static void get_ipsec_sa(struct pktgen_dev *pkt_dev, int flow)
         struct xfrm_state *x = pkt_dev->flows[flow].x;
         struct pktgen_net *pn = net_generic(dev_net(pkt_dev->odev), pg_net_id);
         if (!x) {
-                /*slow path: we dont already have xfrm_state*/
-                x = xfrm_stateonly_find(pn->net, DUMMY_MARK,
-                                        (xfrm_address_t *)&pkt_dev->cur_daddr,
-                                        (xfrm_address_t *)&pkt_dev->cur_saddr,
-                                        AF_INET,
-                                        pkt_dev->ipsmode,
-                                        pkt_dev->ipsproto, 0);
+
+                if (pkt_dev->spi) {
+                        /* We need as quick as possible to find the right SA
+                         * Searching with minimum criteria to archieve this.
+                         */
+                        x = xfrm_state_lookup_byspi(pn->net, htonl(pkt_dev->spi), AF_INET);
+                } else {
+                        /* slow path: we dont already have xfrm_state */
+                        x = xfrm_stateonly_find(pn->net, DUMMY_MARK,
+                                                (xfrm_address_t *)&pkt_dev->cur_daddr,
+                                                (xfrm_address_t *)&pkt_dev->cur_saddr,
+                                                AF_INET,
+                                                pkt_dev->ipsmode,
+                                                pkt_dev->ipsproto, 0);
+                }
                 if (x) {
                         pkt_dev->flows[flow].x = x;
                         set_pkt_overhead(pkt_dev);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 300744094ad8..62181486ead8 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -915,6 +915,28 @@ xfrm_stateonly_find(struct net *net, u32 mark,
 }
 EXPORT_SYMBOL(xfrm_stateonly_find);
 
+struct xfrm_state *xfrm_state_lookup_byspi(struct net *net, __be32 spi,
+                                              unsigned short family)
+{
+        struct xfrm_state *x;
+        struct xfrm_state_walk *w;
+
+        spin_lock_bh(&net->xfrm.xfrm_state_lock);
+        list_for_each_entry(w, &net->xfrm.state_all, all) {
+                x = container_of(w, struct xfrm_state, km);
+                if (x->props.family != family ||
+                        x->id.spi != spi)
+                        continue;
+
+                spin_unlock_bh(&net->xfrm.xfrm_state_lock);
+                xfrm_state_hold(x);
+                return x;
+        }
+        spin_unlock_bh(&net->xfrm.xfrm_state_lock);
+        return NULL;
+}
+EXPORT_SYMBOL(xfrm_state_lookup_byspi);
+
 static void __xfrm_state_insert(struct xfrm_state *x)
 {
         struct net *net = xs_net(x);