[ICMP] replace ICMP offsets by struct IcmpHeader

examples/SSDP/SSDP.ino

@@ -1,4 +1,5 @@
 #include <EtherCard.h>//                                                                                                                                    |Mac adress|
+#include <EtherUtil.h>
 const char SSDP_RESPONSE[] PROGMEM = "HTTP/1.1 200 OK\r\nCACHE-CONTROL: max-age=1200\r\nEXT:\r\nSERVER:Arduino\r\nST: upnp:rootdevice\r\nUSN: uuid:abcdefgh-7dec-11d0-a765-7499692d3040\r\nLOCATION: http://"; //dont forget our mac adress USN: uuid:abcdefgh-7dec-11d0-a765-Mac addr
 const char SSDP_RESPONSE_XML[] PROGMEM = "/??\r\n\r\n"; // here is the adress of xml file /?? in this exemple but you could use another /upnp.xml\r\n\r\n
 const char XML_DESCRIP[] PROGMEM = "HTTP/1.1 200 OK\r\nContent-Type: text/xml\r\n\r\n<?xml version='1.0'?>\r<root xmlns='urn:schemas-upnp-org:device-1-0'><device><deviceType>urn:schemas-upnp-org:device:BinaryLight:1</deviceType><presentationURL>/</presentationURL><friendlyName>Arduino</friendlyName><manufacturer>Fredycpu</manufacturer><manufacturerURL>http://fredycpu.pro</manufacturerURL><serialNumber>1</serialNumber><UDN>uuid:abcdefgh-7dec-11d0-a765-7499692d3040</UDN></device></root>     ";
@@ -48,6 +49,10 @@ const char pageD[] PROGMEM =
 "</em></p>"
 ;
 
+void ssdpresp();
+void addip(uint8_t *udppos);
+void ssdpnotify();
+
 void setup(){
   // Change 'SS' to your Slave Select pin, if you arn't using the default pin
   ether.begin(sizeof Ethernet::buffer, mymac, SS);
@@ -96,46 +101,46 @@ void ssdpresp() { //response to m-search
   for(  int i=0; i<IP_LEN;i++) { //extract source IP of request
     ip_dst[i]=Ethernet::buffer[i+26];
   }
-  int udppos = UDP_DATA_P;
+  uint8_t *udppos = udp_payload();
 
   EtherCard::udpPrepare(1900,ip_dst,port_dst);
-  memcpy_P(Ethernet::buffer + udppos, SSDP_RESPONSE, sizeof SSDP_RESPONSE);
+  memcpy_P(udppos, SSDP_RESPONSE, sizeof SSDP_RESPONSE);
   udppos = udppos  + sizeof SSDP_RESPONSE-1;
   addip(udppos);
 }
 
 void ssdpnotify() { //Notification
-  int udppos = UDP_DATA_P;
+  int udppos = udp_payload();
   EtherCard::udpPrepare(1900,ssdp,1900);
-  memcpy_P(Ethernet::buffer + udppos, SSDP_NOTIFY, sizeof SSDP_NOTIFY);
+  memcpy_P(udppos, SSDP_NOTIFY, sizeof SSDP_NOTIFY);
 udppos = udppos  + sizeof SSDP_NOTIFY-1;
 addip(udppos);
 }
 
-void addip(int udppos) { // add current ip to the request and send it
+void addip(uint8_t *udppos) { // add current ip to the request and send it
   int adr;
   for(int i=0;i<IP_LEN;i++) { // extract the current ip of arduino
     adr = ether.myip[i]/100;
     if (adr)  {
-      Ethernet::buffer[udppos]=adr+48;
+      *udppos=adr+48;
       udppos++;
     }
     adr=(ether.myip[i]%100)/10;
     if (adr||(ether.myip[i]/100))  {
-      Ethernet::buffer[udppos]=adr+48;
+      *udppos=adr+48;
       udppos++;
     }
     adr=ether.myip[i]%10;
-    Ethernet::buffer[udppos]=adr+48;
+    *udppos=adr+48;
     udppos++;
-    Ethernet::buffer[udppos]=46;
+    *udppos=46;
     udppos++; //"."
   }
   udppos--;//erase the last point
-  memcpy_P(Ethernet::buffer + udppos,SSDP_RESPONSE_XML,sizeof SSDP_RESPONSE_XML);
+  memcpy_P(udppos,SSDP_RESPONSE_XML,sizeof SSDP_RESPONSE_XML);
   udppos = udppos  + sizeof SSDP_RESPONSE_XML;
   udppos--;
-  EtherCard::udpTransmit(udppos-UDP_DATA_P); // send all to the computer who make the request on her ip and port who make the request
+  EtherCard::udpTransmit(udppos-udp_payload()); // send all to the computer who make the request on her ip and port who make the request
 }
 
 

src/EtherCard.h

@@ -85,6 +85,11 @@
 */
 #define ETHERCARD_STASH 1
 
+/** Set ARP cache max entry count */
+#ifndef ETHERCARD_ARP_STORE_SIZE
+#   define ETHERCARD_ARP_STORE_SIZE 4
+#endif
+
 
 /** This type definition defines the structure of a UDP server event handler callback function */
 typedef void (*UdpServerCallback)(
@@ -100,6 +105,7 @@ typedef void (*DhcpOptionCallback)(
     const byte* data,   ///< DHCP option data
     uint8_t len);       ///< Length of the DHCP option data
 
+typedef void (*IcmpCallback)(const uint8_t *src_ip);
 
 
 /** This class provides the main interface to a ENC28J60 based network interface card and is the class most users will use.
@@ -190,6 +196,16 @@ class EtherCard : public Ethernet {
     */
     static void updateBroadcastAddress();
 
+    /**   @brief  Request the IP associated hardware address (ARP lookup). Use
+    *             clientWaitIp(ip) to get the ARP lookup status
+    */
+    static void clientResolveIp(const uint8_t *ip);
+
+    /**   @brief  Check if got IP associated hardware address (ARP lookup)
+    *     @return <i>unit8_t</i> True if gateway found
+    */
+    static uint8_t clientWaitIp(const uint8_t *ip);
+
     /**   @brief  Check if got gateway hardware address (ARP lookup)
     *     @return <i>unit8_t</i> True if gateway found
     */
@@ -283,7 +299,7 @@ class EtherCard : public Ethernet {
     /**   @brief  Resister the function to handle ping events
     *     @param  cb Pointer to function
     */
-    static void registerPingCallback (void (*cb)(uint8_t*));
+    static void registerPingCallback (const IcmpCallback cb);
 
     /**   @brief  Send ping
     *     @param  destip Pointer to 4 byte destination IP address
@@ -342,7 +358,7 @@ class EtherCard : public Ethernet {
     *     @param  len Not used
     *     @return <i>bool</i> True if packet processed
     */
-    static bool udpServerHasProcessedPacket(uint16_t len);    //called by tcpip, in packetLoop
+    static bool udpServerHasProcessedPacket(const IpHeader &ip, const uint8_t *iter, const uint8_t *last);    //called by tcpip, in packetLoop
 
     // dhcp.cpp
     /**   @brief  Update DHCP state
@@ -484,6 +500,33 @@ class EtherCard : public Ethernet {
     /**   @brief  Return the payload length of the current Tcp package
     */
     static uint16_t getTcpPayloadLength();
+
+    /**   @brief Check if IP is in ARP store
+    *     @param ip IP to check (size must be IP_LEN)
+    *     @return <i>bool</i> True if IP is in ARP store
+    */
+    static bool arpStoreHasMac(const uint8_t *ip);
+
+    /**   @brief convert IP into associated MAC address
+    *     @param ip IP to convert to MAC address (size must be IP_LEN)
+    *     @return <i>uint8_t *</i> mac MAC address or NULL if not found
+    */
+    static const uint8_t *arpStoreGetMac(const uint8_t *ip);
+
+    /**   @brief set/refresh new couple IP/MAC addresses into ARP store
+    *     @param ip IP address
+    *     @param mac MAC address
+    */
+    static void arpStoreSet(const uint8_t *ip, const uint8_t *mac);
+
+    /**   @brief remove IP from ARP store
+    *     @param ip IP address to remove
+    */
+    static void arpStoreInvalidIp(const uint8_t *ip);
+
+private:
+    static void packetLoopIdle();
+    static void packetLoopArp(const uint8_t *first, const uint8_t *last);
 };
 
 extern EtherCard ether; //!< Global presentation of EtherCard class

src/EtherUtil.h

@@ -0,0 +1,63 @@
+// Shortcuts to different protocols headers/payload
+// Hence: GPL V2
+
+#ifndef ETHERUTIL_H
+#define ETHERUTIL_H
+
+#include "enc28j60.h"
+#include "net.h"
+
+#define gPB ether.buffer
+
+inline EthHeader &ethernet_header()
+{
+    uint8_t *iter = gPB; // avoid strict aliasing warning
+    return *(EthHeader *)iter;
+}
+
+inline uint8_t *ethernet_payload()
+{
+    return (uint8_t *)&ethernet_header() + sizeof(EthHeader);
+}
+
+inline ArpHeader &arp_header()
+{
+    return *(ArpHeader *)ethernet_payload();
+}
+
+inline IpHeader &ip_header()
+{
+    return *(IpHeader *)ethernet_payload();
+}
+
+inline uint8_t *ip_payload()
+{
+    return (uint8_t *)&ip_header() + sizeof(IpHeader);
+}
+
+inline uint8_t *tcp_header()
+{
+    return (uint8_t *)ip_payload();
+}
+
+inline UdpHeader &udp_header()
+{
+    return *(UdpHeader *)ip_payload();
+}
+
+inline uint8_t *udp_payload()
+{
+    return (uint8_t *)&udp_header() + sizeof(UdpHeader);
+}
+
+inline IcmpHeader &icmp_header()
+{
+    return *(IcmpHeader *)ip_payload();
+}
+
+inline uint8_t *icmp_payload()
+{
+    return (uint8_t *)&icmp_header() + sizeof(IcmpHeader);
+}
+
+#endif /* ETHERUTIL_H */

src/arp.cpp

@@ -0,0 +1,93 @@
+#include "EtherCard.h"
+
+struct ArpEntry
+{
+    uint8_t ip[IP_LEN];
+    uint8_t mac[ETH_LEN];
+    uint8_t count;
+};
+
+static ArpEntry store[ETHERCARD_ARP_STORE_SIZE];
+
+static void incArpEntry(ArpEntry &e)
+{
+    if (e.count < 0xFF)
+        ++e.count;
+}
+
+// static ArpEntry print_store()
+// {
+//     Serial.println("ARP store: ");
+//     for (ArpEntry *iter = store, *last = store + ETHERCARD_ARP_STORE_SIZE;
+//             iter != last; ++iter)
+//     {
+//         ArpEntry &e = *iter;
+//         Serial.print('\t');
+//         EtherCard::printIp(e.ip);
+//         Serial.print(' ');
+//         for (int i = 0; i < ETH_LEN; ++i)
+//         {
+//             if (i > 0)
+//                 Serial.print(':');
+//             Serial.print(e.mac[i], HEX);
+//         }
+//         Serial.print(' ');
+//         Serial.println(e.count);
+//     }
+// }
+
+static ArpEntry *findArpStoreEntry(const uint8_t *ip)
+{
+    for (ArpEntry *iter = store, *last = store + ETHERCARD_ARP_STORE_SIZE;
+            iter != last; ++iter)
+    {
+        if (memcmp(ip, iter->ip, IP_LEN) == 0)
+            return iter;
+    }
+    return NULL;
+}
+
+bool EtherCard::arpStoreHasMac(const uint8_t *ip)
+{
+    return findArpStoreEntry(ip) != NULL;
+}
+
+const uint8_t *EtherCard::arpStoreGetMac(const uint8_t *ip)
+{
+    ArpEntry *e = findArpStoreEntry(ip);
+    if (e)
+        return e->mac;
+    return NULL;
+}
+
+void EtherCard::arpStoreSet(const uint8_t *ip, const uint8_t *mac)
+{
+    ArpEntry *e = findArpStoreEntry(ip);
+    if (!e)
+    {
+        // find less used entry
+        e = store;
+        for (ArpEntry *iter = store + 1, *last = store + ETHERCARD_ARP_STORE_SIZE;
+                iter != last; ++iter)
+        {
+            if (iter->count < e->count)
+                e = iter;
+        }
+
+        // and replace it with new ip/mac
+        copyIp(e->ip, ip);
+        e->count = 1;
+    }
+    else
+        incArpEntry(*e);
+
+    copyMac(e->mac, mac);
+    // print_store();
+}
+
+void EtherCard::arpStoreInvalidIp(const uint8_t *ip)
+{
+    ArpEntry *e = findArpStoreEntry(ip);
+    if (e)
+        memset(e, 0, sizeof(ArpEntry));
+}