flow/esp: use spi in hash

Ticket: 8775

Avoids that every flow that is the same except for spi
ends up in the same bucket, and that this bucket grow too much
since FlowCompareESP makes them different flows

src/flow-hash.c

@@ -88,7 +88,10 @@ typedef struct FlowHashKey4_ {
     union {
         struct {
             uint32_t addrs[2];
-            uint16_t ports[2];
+            union {
+                uint16_t ports[2];
+                uint32_t esp_spi;
+            };
             uint8_t proto; /**< u8 so proto and recur and livedev add up to u32 */
             uint8_t recur;
             uint16_t livedev;
@@ -103,7 +106,10 @@ typedef struct FlowHashKey6_ {
     union {
         struct {
             uint32_t src[4], dst[4];
-            uint16_t ports[2];
+            union {
+                uint16_t ports[2];
+                uint32_t esp_spi;
+            };
             uint8_t proto; /**< u8 so proto and recur and livedev add up to u32 */
             uint8_t recur;
             uint16_t livedev;
@@ -251,8 +257,12 @@ static inline uint32_t FlowGetHash(const Packet *p)
             const int ai = (p->src.addr_data32[0] > p->dst.addr_data32[0]);
             fhk.addrs[1-ai] = p->src.addr_data32[0];
             fhk.addrs[ai] = p->dst.addr_data32[0];
-            fhk.ports[0] = 0xfeed;
-            fhk.ports[1] = 0xbeef;
+            if (PacketIsESP(p)) {
+                fhk.esp_spi = ESP_GET_SPI(PacketGetESP(p));
+            } else {
+                fhk.ports[0] = 0xfeed;
+                fhk.ports[1] = 0xbeef;
+            }
             FlowHashIp4Fill(&fhk, p);
 
             hash = hashword(fhk.u32, ARRAY_SIZE(fhk.u32), flow_config.hash_rand);
@@ -280,8 +290,12 @@ static inline uint32_t FlowGetHash(const Packet *p)
         }
 
         const int pi = (p->sp > p->dp);
-        fhk.ports[1-pi] = p->sp;
-        fhk.ports[pi] = p->dp;
+        if (PacketIsESP(p)) {
+            fhk.esp_spi = ESP_GET_SPI(PacketGetESP(p));
+        } else {
+            fhk.ports[1 - pi] = p->sp;
+            fhk.ports[pi] = p->dp;
+        }
         FlowHashIp6Fill(&fhk, p);
 
         hash = hashword(fhk.u32, ARRAY_SIZE(fhk.u32), flow_config.hash_rand);