Merge "Manipulating the TTL of the Packet" into R3.1

Juniper · Jul 31, 2016 · 24cf44f · 24cf44f
2 parents 47d62dc + 42bd7dd
commit 24cf44f
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Showing 6 changed files with 34 additions and 4 deletions.
diff --git a/dp-core/vr_flow.c b/dp-core/vr_flow.c
@@ -222,6 +222,7 @@ __vr_flow_reset_entry(struct vrouter *router, struct vr_flow_entry *fe)
     fe->fe_flags &=
         (VR_FLOW_FLAG_ACTIVE | VR_FLOW_FLAG_EVICTED |
          VR_FLOW_FLAG_NEW_FLOW | VR_FLOW_FLAG_DELETE_MARKED);
+    fe->fe_ttl = 0;
 
     return;
 }
@@ -778,6 +779,8 @@ vr_flow_action(struct vrouter *router, struct vr_flow_entry *fe,
         struct vr_forwarding_md *fmd)
 {
     int valid_src;
+    unsigned int ip_inc_diff_cksum = 0;
+    struct vr_ip *ip;
 
     flow_result_t result;
 
@@ -861,6 +864,22 @@ vr_flow_action(struct vrouter *router, struct vr_flow_entry *fe,
         break;
     }
 
+    if (result == FLOW_FORWARD) {
+        if (pkt->vp_type == VP_TYPE_IP) {
+            ip = (struct vr_ip *)pkt_network_header(pkt);
+            if (ip) {
+                if (fe->fe_ttl && (fe->fe_ttl != ip->ip_ttl)) {
+                    vr_incremental_diff(ip->ip_ttl, fe->fe_ttl, &ip_inc_diff_cksum);
+                    ip->ip_ttl = fe->fe_ttl;
+
+                    if (ip_inc_diff_cksum)
+                        vr_ip_incremental_csum(ip, ip_inc_diff_cksum);
+                }
+            }
+        }
+    }
+
+
     if (fe->fe_tcp_flags & VR_FLOW_TCP_DEAD)
         vr_flow_mark_evict(router, fe, index);
 
@@ -1956,6 +1975,8 @@ vr_flow_set(struct vrouter *router, vr_flow_req *req)
         fe->fe_action = req->fr_action;
     }
 
+    fe->fe_ttl = req->fr_ttl;
+
     if (fe->fe_action == VR_FLOW_ACTION_DROP)
         fe->fe_drop_reason = (uint8_t)req->fr_drop_reason;
 

diff --git a/dp-core/vr_proto_ip.c b/dp-core/vr_proto_ip.c
@@ -97,7 +97,8 @@ vr_ip_update_csum(struct vr_packet *pkt, unsigned int ip_inc, unsigned int inc)
     unsigned short *csump;
 
     ip = (struct vr_ip *)pkt_network_header(pkt);
-    ip->ip_csum = vr_ip_csum(ip);
+    if (ip_inc)
+        vr_ip_incremental_csum(ip, ip_inc);
 
     if (ip->ip_proto == VR_IP_PROTO_TCP) {
         tcp = (struct vr_tcp *)((unsigned char *)ip + ip->ip_hl * 4);

diff --git a/include/vr_flow.h b/include/vr_flow.h
@@ -301,7 +301,7 @@ struct vr_flow_queue {
 
 struct vr_dummy_flow_entry {
     vr_hentry_t fe_hentry;
-    uint8_t fe_pack_hentry;
+    uint8_t fe_ttl;
     int16_t fe_qos_id;
     struct vr_flow fe_key;
     uint8_t fe_gen_id;
@@ -329,7 +329,7 @@ struct vr_dummy_flow_entry {
 /* do not change. any field positions as it might lead to incompatibility */
 struct vr_flow_entry {
     vr_hentry_t fe_hentry;
-    uint8_t fe_pack_hentry;
+    uint8_t fe_ttl;
     int16_t fe_qos_id;
     struct vr_flow fe_key;
     uint8_t fe_gen_id;

diff --git a/include/vr_packet.h b/include/vr_packet.h
@@ -412,7 +412,12 @@ vr_ip_incremental_csum(struct vr_ip *ip, unsigned int diff)
 {
     unsigned int csum;
 
-    diff &= 0xffff;
+    diff = (diff >> 16) + (diff & 0xffff);
+    if (diff >> 16) {
+        diff &= 0xffff;
+        diff += 1;
+    }
+
     csum = ~(ip->ip_csum) & 0xffff;
     csum += diff;
     csum = (csum >> 16) + (csum & 0xffff);
@@ -707,6 +712,7 @@ vr_ip_transport_header_valid(struct vr_ip *iph)
 }
 
 
+
 #define VR_TCP_FLAG_FIN         0x0001
 #define VR_TCP_FLAG_SYN         0x0002
 #define VR_TCP_FLAG_RST         0x0004

diff --git a/sandesh/vr.sandesh b/sandesh/vr.sandesh
@@ -191,6 +191,7 @@ buffer sandesh vr_flow_req {
    36: i32          fr_oflow_entries;
    37: byte         fr_gen_id;
    38: i16          fr_qos_id;
+   39: byte         fr_ttl;
 }
 
 buffer sandesh vr_vrf_assign_req {

diff --git a/utils/flow.c b/utils/flow.c
@@ -1401,6 +1401,7 @@ flow_dump_table(struct flow_table *ft)
                     printf(", %d, ", fe->fe_sec_mirror_id);
             }
             printf(" SPort %d", fe->fe_udp_src_port);
+            printf(" TTL %d", fe->fe_ttl);
             printf(")");
         }