mips_sys

@@ -18,11 +18,11 @@

 #define ARP_TAB_FLAG_MAC_OK (2)

 struct arp_table

 {

-  unsigned char flags; /// flags - see constants

-  unsigned char ticks; /// age of entry in 200ms steps

+  unsigned int flags; /// flags - see constants

+  unsigned int ticks; /// age of entry in 200ms steps

   unsigned char mac[6];

   unsigned char ip[4];

-} arp_tab[12];

+} arp_tab[16];

 /**

  * @brief send an ARP request

@@ -144,28 +144,16 @@ void arp_recv(void *ptr, unsigned int sz)

   if (arp_pack->arp_hdr.op == htons(0x0002) && // ARP reply

       mac_eq(arp_pack->arp_hdr.dest_mac, config_mac.mac) && // own MAC address

       ip_eq(arp_pack->arp_hdr.dest_ip, config_ip.ip)) { // own IP address

-    unsigned int i;

-    // search IP in ARP tabale

-    for (i = 0; i < count(arp_tab); ++i)

-      if ((arp_tab[i].flags & ARP_TAB_FLAG_IN_USE) &&

-          ip_eq(arp_pack->arp_hdr.src_ip, arp_tab[i].ip))

-        break;

-    // if found in ARP table

-    // (we do not want to put an entry in the ARP table

-    //  if we have not asked for the MAC of this IP)

-    if (i < count(arp_tab)) {

-      // update ARP table entry

-      arp_tab[i].flags = ARP_TAB_FLAG_IN_USE | ARP_TAB_FLAG_MAC_OK;

-      arp_tab[i].ticks = 0;

-      mac_cpy(arp_tab[i].mac, arp_pack->arp_hdr.src_mac);

+    // store MAC for IP

+    arp_store(arp_pack->arp_hdr.src_ip, arp_pack->arp_hdr.src_mac);

+

     // notify IP

     //  - IP might be waiting for the MAC to transmit a packet

-      ip_got_mac(arp_tab[i].ip, arp_tab[i].mac);

-    }

+    ip_got_mac(arp_pack->arp_hdr.src_ip, arp_pack->arp_hdr.src_mac);

+

     return;

   }

-

 }

 /**

@@ -225,3 +213,47 @@ int arp_lookup(unsigned char ip[4], unsigned char mac[6])

   return 1;

 }

+/**

+ * @brief store the MAC for an IP address

+ * @param[in] ip IP address to store MAC for

+ * @param[out] mac MAC address for this IP address

+ */

+void arp_store(unsigned char ip[4], unsigned char mac[6])

+{

+  unsigned int i, j;

+

+  // search IP in ARP table

+  for (i = 0; i < count(arp_tab); ++i) {

+    if ((arp_tab[i].flags & ARP_TAB_FLAG_IN_USE) &&

+        ip_eq(ip, arp_tab[i].ip))

+      break;

+  }

+

+  // not found

+  if (i >= count(arp_tab)) {

+    // find a free entry

+    for (i = 0; i < count(arp_tab); ++i)

+      if (!(arp_tab[i].flags & ARP_TAB_FLAG_IN_USE))

+        break;

+

+    // no free entry

+    if (i >= count(arp_tab)) {

+      // find oldest entry

+      i = 0;

+      for (j = 1; j < count(arp_tab); ++j)

+        if (arp_tab[j].ticks > arp_tab[i].ticks )

+          i = j;

+    }

+

+    // set up this entry

+    arp_tab[i].flags = ARP_TAB_FLAG_IN_USE;

+    arp_tab[i].ticks = 0;

+    ip_cpy(arp_tab[i].ip, ip);

+  }

+

+  // update ARP table entry

+  arp_tab[i].flags = ARP_TAB_FLAG_IN_USE | ARP_TAB_FLAG_MAC_OK;

+  arp_tab[i].ticks = 0;

+  mac_cpy(arp_tab[i].mac, mac);

+}

+

@@ -45,5 +45,12 @@ void arp_recv(void *ptr, unsigned int sz);

  */

 int arp_lookup(unsigned char ip[4], unsigned char mac[6]);

+/**

+ * @brief store the MAC for an IP address

+ * @param[in] ip IP address to store MAC for

+ * @param[out] mac MAC address for this IP address

+ */

+void arp_store(unsigned char ip[4], unsigned char mac[6]);

+

 #endif // #ifdef ARP_H

@@ -30,7 +30,7 @@ struct ip_buffer_table

   void *ptr; ///< pointer to buffer for packet

   unsigned int buf_sz; ///< size of buffer

   unsigned int pkg_sz; ///< size of packet in buffer, 0 for packet

-  unsigned int ticks; //< age of entry (in 200ms)

+  unsigned int ticks; ///< age of entry (in 200ms)

 } ip_buffer_tab[] =

 { // put smaller buffers in front of larger buffers

   //  - then short packets will use smaller buffers more often

@@ -130,8 +130,7 @@ void ip_recv(void *ptr, unsigned int sz)

       (ip_pack->ip_hdr.src[2] & config_ip.mask[2]) ==

         (config_ip.ip[2] & config_ip.mask[2]) &&

       (ip_pack->ip_hdr.src[3] & config_ip.mask[3]) ==

-        (config_ip.ip[3] & config_ip.mask[3]))

-  {

+        (config_ip.ip[3] & config_ip.mask[3])) {

     // local network address

     if ((ip_pack->ip_hdr.src[0] & ~config_ip.mask[0]) == 0x00 &&

         (ip_pack->ip_hdr.src[1] & ~config_ip.mask[1]) == 0x00 &&

@@ -166,6 +165,9 @@ void ip_recv(void *ptr, unsigned int sz)

   if (checksum(&ip_pack->ip_hdr, sizeof(struct ip_header), 0x0000, 0x0000))

     return;

+  // save MAC/IP information in ARP table

+  arp_store(ip_pack->ip_hdr.src, ip_pack->eth_hdr.src);

+

   // branch according to protocol

   switch (ip_pack->ip_hdr.proto) {

     // ICMP

@@ -240,7 +242,7 @@ void ip_send(void *ptr, unsigned int sz)

   // find a buffer to store the packet in

   for (i = 0; i < count(ip_buffer_tab); i++) {

     if (ip_buffer_tab[i].pkg_sz == 0 && // buffer not in use

-        sz < ip_buffer_tab[i].buf_sz) { // buffer long enough

+        sz <= ip_buffer_tab[i].buf_sz) { // buffer long enough

       // put packet into buffer

       memcpy(ip_buffer_tab[i].ptr, ptr, sz);

       ip_buffer_tab[i].pkg_sz = sz;