Merge pull request wolfSSL#44 from danielinux/arp-fix-neighbor-cache

ARP bugfix: wrong mac address stored in neighbor cache

Author: LinuxJedi

src/test/unit/unit.c

@@ -14337,7 +14337,7 @@ START_TEST(test_arp_request_handling) {
     uint32_t req_ip = 0xC0A80002; // 192.168.0.2
     uint32_t device_ip = 0xC0A80001; // 192.168.0.1
     uint8_t req_mac[6] = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF};
-    //uint8_t mac[6] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55};
+    uint8_t mac[6] = {0};
     struct wolfIP s;
 
     memset(&arp_req, 0, sizeof(arp_req));
@@ -14358,9 +14358,8 @@ START_TEST(test_arp_request_handling) {
     wolfIP_poll(&s, 1002);
 
     /* Check if ARP table updated with requester's MAC and IP */
-    /* TODO */
-    //ck_assert_int_eq(arp_lookup(&s, req_ip, mac), 0);
-    //ck_assert_mem_eq(mac, req_mac, 6);
+    ck_assert_int_eq(arp_lookup(&s, TEST_PRIMARY_IF, req_ip, mac), 0);
+    ck_assert_mem_eq(mac, req_mac, 6);
 
     /* Check if an ARP reply was generated */
     arp_reply = (struct arp_packet *)last_frame_sent;

src/wolfip.c

@@ -5068,12 +5068,15 @@ static void arp_recv(struct wolfIP *s, unsigned int if_idx, void *buf, int len)
         return;
 
     if (arp->opcode == ee16(ARP_REQUEST) && arp->tip == ee32(conf->ip)) {
+        uint32_t sender_ip = arp->sip;
+        uint8_t sender_mac[6];
+        memcpy(sender_mac, arp->sma, 6);
         arp->opcode = ee16(ARP_REPLY);
         memcpy(arp->tma, arp->sma, 6);
         memcpy(arp->sma, ll->mac, 6);
         arp->tip = arp->sip;
         arp->sip = ee32(conf->ip);
-        arp_store_neighbor(s, if_idx, ee32(arp->sip), arp->sma);
+        arp_store_neighbor(s, if_idx, ee32(sender_ip), sender_mac);
         eth_output_add_header(s, if_idx, arp->tma, &arp->eth, ETH_TYPE_ARP);
         if (ll->send) {
             if (wolfIP_filter_notify_eth(WOLFIP_FILT_SENDING, s, if_idx, &arp->eth, len) != 0)