[EFR32] Adds fix for IPv6 SLAAC DAD process loopback suppression (#23160

) * Adds fix for loop back suppression during duplicate address detection process * Added changes based on comments * Adds fix for temporary loopback suppression during DAD process
project-chip · Sep 5, 2023 · 5ba5f7c · 5ba5f7c
1 parent 068bd1d
commit 5ba5f7c
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Showing 3 changed files with 32 additions and 7 deletions.
diff --git a/src/lwip/efr32/lwipopts-rs911x.h b/src/lwip/efr32/lwipopts-rs911x.h
@@ -99,7 +99,7 @@
 #define LWIP_IPV6_REASS (0)
 #define LWIP_IPV6_DHCP6 0
 #define LWIP_IPV6_AUTOCONFIG (1)
-#define LWIP_IPV6_DUP_DETECT_ATTEMPTS 0 // TODO: Enable this after a fix for NS loopback
+#define LWIP_IPV6_DUP_DETECT_ATTEMPTS 1
 #define LWIP_IPV6_ROUTER_SUPPORT 1
 #define LWIP_ND6_LISTEN_RA 1
 

diff --git a/src/lwip/efr32/lwipopts-wf200.h b/src/lwip/efr32/lwipopts-wf200.h
@@ -99,7 +99,7 @@
 #define LWIP_IPV6_REASS (0)
 #define LWIP_IPV6_DHCP6 0
 #define LWIP_IPV6_AUTOCONFIG (1)
-#define LWIP_IPV6_DUP_DETECT_ATTEMPTS 0 // TODO: Enable this after a fix for NS loopback
+#define LWIP_IPV6_DUP_DETECT_ATTEMPTS 1
 #define LWIP_IPV6_ROUTER_SUPPORT 1
 #define LWIP_ND6_LISTEN_RA 1
 

diff --git a/src/platform/EFR32/wifi/ethernetif.cpp b/src/platform/EFR32/wifi/ethernetif.cpp
@@ -121,10 +121,30 @@ static void low_level_input(struct netif * netif, uint8_t * b, uint16_t len)
     {
         return;
     }
-    if (len < 60)
+    if (len < LWIP_FRAME_ALIGNMENT)
     { /* 60 : LWIP frame alignment */
-        len = 60;
+        len = LWIP_FRAME_ALIGNMENT;
     }
+
+    /* Drop packets originated from the same interface and is not destined for the said interface */
+    const uint8_t * src_mac = b + netif->hwaddr_len;
+    const uint8_t * dst_mac = b;
+
+    if (!(ip6_addr_ispreferred(netif_ip6_addr_state(netif, 0))) && (memcmp(netif->hwaddr, src_mac, netif->hwaddr_len) == 0) &&
+        (memcmp(netif->hwaddr, dst_mac, netif->hwaddr_len) != 0))
+    {
+#ifdef WIFI_DEBUG_ENABLED
+        EFR32_LOG("%s: DROP, [%02x:%02x:%02x:%02x:%02x:%02x]<-[%02x:%02x:%02x:%02x:%02x:%02x] type=%02x%02x", __func__,
+
+                  dst_mac[0], dst_mac[1], dst_mac[2], dst_mac[3], dst_mac[4], dst_mac[5],
+
+                  src_mac[0], src_mac[1], src_mac[2], src_mac[3], src_mac[4], src_mac[5],
+
+                  b[12], b[13]);
+#endif
+        return;
+    }
+
     /* We allocate a pbuf chain of pbufs from the Lwip buffer pool
      * and copy the data to the pbuf chain
      */
@@ -135,10 +155,15 @@ static void low_level_input(struct netif * netif, uint8_t * b, uint16_t len)
             memcpy((uint8_t *) q->payload, (uint8_t *) b + bufferoffset, q->len);
             bufferoffset += q->len;
         }
-
 #ifdef WIFI_DEBUG_ENABLED
-        EFR32_LOG("EN:IN %d,[%02x:%02x:%02x:%02x:%02x%02x][%02x:%02x:%02x:%02x:%02x:%02x]type=%02x%02x", bufferoffset, b[0], b[1],
-                  b[2], b[3], b[4], b[5], b[6], b[7], b[8], b[9], b[10], b[11], b[12], b[13]);
+        EFR32_LOG("%s: ACCEPT %d, [%02x:%02x:%02x:%02x:%02x:%02x]<-[%02x:%02x:%02x:%02x:%02x:%02x] type=%02x%02x", __func__,
+                  bufferoffset,
+
+                  dst_mac[0], dst_mac[1], dst_mac[2], dst_mac[3], dst_mac[4], dst_mac[5],
+
+                  src_mac[0], src_mac[1], src_mac[2], src_mac[3], src_mac[4], src_mac[5],
+
+                  b[12], b[13]);
 #endif
 
         if (netif->input(p, netif) != ERR_OK)