diff options
Diffstat (limited to 'libraries/Ethernet/Dhcp.cpp')
| -rw-r--r-- | libraries/Ethernet/Dhcp.cpp | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/libraries/Ethernet/Dhcp.cpp b/libraries/Ethernet/Dhcp.cpp new file mode 100644 index 0000000..56d5b69 --- /dev/null +++ b/libraries/Ethernet/Dhcp.cpp @@ -0,0 +1,480 @@ +// DHCP Library v0.3 - April 25, 2009
+// Author: Jordan Terrell - blog.jordanterrell.com
+
+#include "w5100.h"
+
+#include <string.h>
+#include <stdlib.h>
+#include "Dhcp.h"
+#include "Arduino.h"
+#include "util.h"
+
+int DhcpClass::beginWithDHCP(uint8_t *mac, unsigned long timeout, unsigned long responseTimeout)
+{
+ _dhcpLeaseTime=0;
+ _dhcpT1=0;
+ _dhcpT2=0;
+ _lastCheck=0;
+ _timeout = timeout;
+ _responseTimeout = responseTimeout;
+
+ // zero out _dhcpMacAddr
+ memset(_dhcpMacAddr, 0, 6);
+ reset_DHCP_lease();
+
+ memcpy((void*)_dhcpMacAddr, (void*)mac, 6);
+ _dhcp_state = STATE_DHCP_START;
+ return request_DHCP_lease();
+}
+
+void DhcpClass::reset_DHCP_lease(){
+ // zero out _dhcpSubnetMask, _dhcpGatewayIp, _dhcpLocalIp, _dhcpDhcpServerIp, _dhcpDnsServerIp
+ memset(_dhcpLocalIp, 0, 20);
+}
+
+//return:0 on error, 1 if request is sent and response is received
+int DhcpClass::request_DHCP_lease(){
+
+ uint8_t messageType = 0;
+
+
+
+ // Pick an initial transaction ID
+ _dhcpTransactionId = random(1UL, 2000UL);
+ _dhcpInitialTransactionId = _dhcpTransactionId;
+
+ _dhcpUdpSocket.stop();
+ if (_dhcpUdpSocket.begin(DHCP_CLIENT_PORT) == 0)
+ {
+ // Couldn't get a socket
+ return 0;
+ }
+
+ presend_DHCP();
+
+ int result = 0;
+
+ unsigned long startTime = millis();
+
+ while(_dhcp_state != STATE_DHCP_LEASED)
+ {
+ if(_dhcp_state == STATE_DHCP_START)
+ {
+ _dhcpTransactionId++;
+
+ send_DHCP_MESSAGE(DHCP_DISCOVER, ((millis() - startTime) / 1000));
+ _dhcp_state = STATE_DHCP_DISCOVER;
+ }
+ else if(_dhcp_state == STATE_DHCP_REREQUEST){
+ _dhcpTransactionId++;
+ send_DHCP_MESSAGE(DHCP_REQUEST, ((millis() - startTime)/1000));
+ _dhcp_state = STATE_DHCP_REQUEST;
+ }
+ else if(_dhcp_state == STATE_DHCP_DISCOVER)
+ {
+ uint32_t respId;
+ messageType = parseDHCPResponse(_responseTimeout, respId);
+ if(messageType == DHCP_OFFER)
+ {
+ // We'll use the transaction ID that the offer came with,
+ // rather than the one we were up to
+ _dhcpTransactionId = respId;
+ send_DHCP_MESSAGE(DHCP_REQUEST, ((millis() - startTime) / 1000));
+ _dhcp_state = STATE_DHCP_REQUEST;
+ }
+ }
+ else if(_dhcp_state == STATE_DHCP_REQUEST)
+ {
+ uint32_t respId;
+ messageType = parseDHCPResponse(_responseTimeout, respId);
+ if(messageType == DHCP_ACK)
+ {
+ _dhcp_state = STATE_DHCP_LEASED;
+ result = 1;
+ //use default lease time if we didn't get it
+ if(_dhcpLeaseTime == 0){
+ _dhcpLeaseTime = DEFAULT_LEASE;
+ }
+ //calculate T1 & T2 if we didn't get it
+ if(_dhcpT1 == 0){
+ //T1 should be 50% of _dhcpLeaseTime
+ _dhcpT1 = _dhcpLeaseTime >> 1;
+ }
+ if(_dhcpT2 == 0){
+ //T2 should be 87.5% (7/8ths) of _dhcpLeaseTime
+ _dhcpT2 = _dhcpT1 << 1;
+ }
+ _renewInSec = _dhcpT1;
+ _rebindInSec = _dhcpT2;
+ }
+ else if(messageType == DHCP_NAK)
+ _dhcp_state = STATE_DHCP_START;
+ }
+
+ if(messageType == 255)
+ {
+ messageType = 0;
+ _dhcp_state = STATE_DHCP_START;
+ }
+
+ if(result != 1 && ((millis() - startTime) > _timeout))
+ break;
+ }
+
+ // We're done with the socket now
+ _dhcpUdpSocket.stop();
+ _dhcpTransactionId++;
+
+ return result;
+}
+
+void DhcpClass::presend_DHCP()
+{
+}
+
+void DhcpClass::send_DHCP_MESSAGE(uint8_t messageType, uint16_t secondsElapsed)
+{
+ uint8_t buffer[32];
+ memset(buffer, 0, 32);
+ IPAddress dest_addr( 255, 255, 255, 255 ); // Broadcast address
+
+ if (-1 == _dhcpUdpSocket.beginPacket(dest_addr, DHCP_SERVER_PORT))
+ {
+ // FIXME Need to return errors
+ return;
+ }
+
+ buffer[0] = DHCP_BOOTREQUEST; // op
+ buffer[1] = DHCP_HTYPE10MB; // htype
+ buffer[2] = DHCP_HLENETHERNET; // hlen
+ buffer[3] = DHCP_HOPS; // hops
+
+ // xid
+ unsigned long xid = htonl(_dhcpTransactionId);
+ memcpy(buffer + 4, &(xid), 4);
+
+ // 8, 9 - seconds elapsed
+ buffer[8] = ((secondsElapsed & 0xff00) >> 8);
+ buffer[9] = (secondsElapsed & 0x00ff);
+
+ // flags
+ unsigned short flags = htons(DHCP_FLAGSBROADCAST);
+ memcpy(buffer + 10, &(flags), 2);
+
+ // ciaddr: already zeroed
+ // yiaddr: already zeroed
+ // siaddr: already zeroed
+ // giaddr: already zeroed
+
+ //put data in W5100 transmit buffer
+ _dhcpUdpSocket.write(buffer, 28);
+
+ memset(buffer, 0, 32); // clear local buffer
+
+ memcpy(buffer, _dhcpMacAddr, 6); // chaddr
+
+ //put data in W5100 transmit buffer
+ _dhcpUdpSocket.write(buffer, 16);
+
+ memset(buffer, 0, 32); // clear local buffer
+
+ // leave zeroed out for sname && file
+ // put in W5100 transmit buffer x 6 (192 bytes)
+
+ for(int i = 0; i < 6; i++) {
+ _dhcpUdpSocket.write(buffer, 32);
+ }
+
+ // OPT - Magic Cookie
+ buffer[0] = (uint8_t)((MAGIC_COOKIE >> 24)& 0xFF);
+ buffer[1] = (uint8_t)((MAGIC_COOKIE >> 16)& 0xFF);
+ buffer[2] = (uint8_t)((MAGIC_COOKIE >> 8)& 0xFF);
+ buffer[3] = (uint8_t)(MAGIC_COOKIE& 0xFF);
+
+ // OPT - message type
+ buffer[4] = dhcpMessageType;
+ buffer[5] = 0x01;
+ buffer[6] = messageType; //DHCP_REQUEST;
+
+ // OPT - client identifier
+ buffer[7] = dhcpClientIdentifier;
+ buffer[8] = 0x07;
+ buffer[9] = 0x01;
+ memcpy(buffer + 10, _dhcpMacAddr, 6);
+
+ // OPT - host name
+ buffer[16] = hostName;
+ buffer[17] = strlen(HOST_NAME) + 6; // length of hostname + last 3 bytes of mac address
+ strcpy((char*)&(buffer[18]), HOST_NAME);
+
+ printByte((char*)&(buffer[24]), _dhcpMacAddr[3]);
+ printByte((char*)&(buffer[26]), _dhcpMacAddr[4]);
+ printByte((char*)&(buffer[28]), _dhcpMacAddr[5]);
+
+ //put data in W5100 transmit buffer
+ _dhcpUdpSocket.write(buffer, 30);
+
+ if(messageType == DHCP_REQUEST)
+ {
+ buffer[0] = dhcpRequestedIPaddr;
+ buffer[1] = 0x04;
+ buffer[2] = _dhcpLocalIp[0];
+ buffer[3] = _dhcpLocalIp[1];
+ buffer[4] = _dhcpLocalIp[2];
+ buffer[5] = _dhcpLocalIp[3];
+
+ buffer[6] = dhcpServerIdentifier;
+ buffer[7] = 0x04;
+ buffer[8] = _dhcpDhcpServerIp[0];
+ buffer[9] = _dhcpDhcpServerIp[1];
+ buffer[10] = _dhcpDhcpServerIp[2];
+ buffer[11] = _dhcpDhcpServerIp[3];
+
+ //put data in W5100 transmit buffer
+ _dhcpUdpSocket.write(buffer, 12);
+ }
+
+ buffer[0] = dhcpParamRequest;
+ buffer[1] = 0x06;
+ buffer[2] = subnetMask;
+ buffer[3] = routersOnSubnet;
+ buffer[4] = dns;
+ buffer[5] = domainName;
+ buffer[6] = dhcpT1value;
+ buffer[7] = dhcpT2value;
+ buffer[8] = endOption;
+
+ //put data in W5100 transmit buffer
+ _dhcpUdpSocket.write(buffer, 9);
+
+ _dhcpUdpSocket.endPacket();
+}
+
+uint8_t DhcpClass::parseDHCPResponse(unsigned long responseTimeout, uint32_t& transactionId)
+{
+ uint8_t type = 0;
+ uint8_t opt_len = 0;
+
+ unsigned long startTime = millis();
+
+ while(_dhcpUdpSocket.parsePacket() <= 0)
+ {
+ if((millis() - startTime) > responseTimeout)
+ {
+ return 255;
+ }
+ delay(50);
+ }
+ // start reading in the packet
+ RIP_MSG_FIXED fixedMsg;
+ _dhcpUdpSocket.read((uint8_t*)&fixedMsg, sizeof(RIP_MSG_FIXED));
+
+ if(fixedMsg.op == DHCP_BOOTREPLY && _dhcpUdpSocket.remotePort() == DHCP_SERVER_PORT)
+ {
+ transactionId = ntohl(fixedMsg.xid);
+ if(memcmp(fixedMsg.chaddr, _dhcpMacAddr, 6) != 0 || (transactionId < _dhcpInitialTransactionId) || (transactionId > _dhcpTransactionId))
+ {
+ // Need to read the rest of the packet here regardless
+ _dhcpUdpSocket.flush();
+ return 0;
+ }
+
+ memcpy(_dhcpLocalIp, fixedMsg.yiaddr, 4);
+
+ // Skip to the option part
+ // Doing this a byte at a time so we don't have to put a big buffer
+ // on the stack (as we don't have lots of memory lying around)
+ for (int i =0; i < (240 - (int)sizeof(RIP_MSG_FIXED)); i++)
+ {
+ _dhcpUdpSocket.read(); // we don't care about the returned byte
+ }
+
+ while (_dhcpUdpSocket.available() > 0)
+ {
+ switch (_dhcpUdpSocket.read())
+ {
+ case endOption :
+ break;
+
+ case padOption :
+ break;
+
+ case dhcpMessageType :
+ opt_len = _dhcpUdpSocket.read();
+ type = _dhcpUdpSocket.read();
+ break;
+
+ case subnetMask :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read(_dhcpSubnetMask, 4);
+ break;
+
+ case routersOnSubnet :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read(_dhcpGatewayIp, 4);
+ for (int i = 0; i < opt_len-4; i++)
+ {
+ _dhcpUdpSocket.read();
+ }
+ break;
+
+ case dns :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read(_dhcpDnsServerIp, 4);
+ for (int i = 0; i < opt_len-4; i++)
+ {
+ _dhcpUdpSocket.read();
+ }
+ break;
+
+ case dhcpServerIdentifier :
+ opt_len = _dhcpUdpSocket.read();
+ if( *((uint32_t*)_dhcpDhcpServerIp) == 0 ||
+ IPAddress(_dhcpDhcpServerIp) == _dhcpUdpSocket.remoteIP() )
+ {
+ _dhcpUdpSocket.read(_dhcpDhcpServerIp, sizeof(_dhcpDhcpServerIp));
+ }
+ else
+ {
+ // Skip over the rest of this option
+ while (opt_len--)
+ {
+ _dhcpUdpSocket.read();
+ }
+ }
+ break;
+
+ case dhcpT1value :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read((uint8_t*)&_dhcpT1, sizeof(_dhcpT1));
+ _dhcpT1 = ntohl(_dhcpT1);
+ break;
+
+ case dhcpT2value :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read((uint8_t*)&_dhcpT2, sizeof(_dhcpT2));
+ _dhcpT2 = ntohl(_dhcpT2);
+ break;
+
+ case dhcpIPaddrLeaseTime :
+ opt_len = _dhcpUdpSocket.read();
+ _dhcpUdpSocket.read((uint8_t*)&_dhcpLeaseTime, sizeof(_dhcpLeaseTime));
+ _dhcpLeaseTime = ntohl(_dhcpLeaseTime);
+ _renewInSec = _dhcpLeaseTime;
+ break;
+
+ default :
+ opt_len = _dhcpUdpSocket.read();
+ // Skip over the rest of this option
+ while (opt_len--)
+ {
+ _dhcpUdpSocket.read();
+ }
+ break;
+ }
+ }
+ }
+
+ // Need to skip to end of the packet regardless here
+ _dhcpUdpSocket.flush();
+
+ return type;
+}
+
+
+/*
+ returns:
+ 0/DHCP_CHECK_NONE: nothing happened
+ 1/DHCP_CHECK_RENEW_FAIL: renew failed
+ 2/DHCP_CHECK_RENEW_OK: renew success
+ 3/DHCP_CHECK_REBIND_FAIL: rebind fail
+ 4/DHCP_CHECK_REBIND_OK: rebind success
+*/
+int DhcpClass::checkLease(){
+ //this uses a signed / unsigned trick to deal with millis overflow
+ unsigned long now = millis();
+ signed long snow = (long)now;
+ int rc=DHCP_CHECK_NONE;
+ if (_lastCheck != 0){
+ signed long factor;
+ //calc how many ms past the timeout we are
+ factor = snow - (long)_secTimeout;
+ //if on or passed the timeout, reduce the counters
+ if ( factor >= 0 ){
+ //next timeout should be now plus 1000 ms minus parts of second in factor
+ _secTimeout = snow + 1000 - factor % 1000;
+ //how many seconds late are we, minimum 1
+ factor = factor / 1000 +1;
+
+ //reduce the counters by that mouch
+ //if we can assume that the cycle time (factor) is fairly constant
+ //and if the remainder is less than cycle time * 2
+ //do it early instead of late
+ if(_renewInSec < factor*2 )
+ _renewInSec = 0;
+ else
+ _renewInSec -= factor;
+
+ if(_rebindInSec < factor*2 )
+ _rebindInSec = 0;
+ else
+ _rebindInSec -= factor;
+ }
+
+ //if we have a lease but should renew, do it
+ if (_dhcp_state == STATE_DHCP_LEASED && _renewInSec <=0){
+ _dhcp_state = STATE_DHCP_REREQUEST;
+ rc = 1 + request_DHCP_lease();
+ }
+
+ //if we have a lease or is renewing but should bind, do it
+ if( (_dhcp_state == STATE_DHCP_LEASED || _dhcp_state == STATE_DHCP_START) && _rebindInSec <=0){
+ //this should basically restart completely
+ _dhcp_state = STATE_DHCP_START;
+ reset_DHCP_lease();
+ rc = 3 + request_DHCP_lease();
+ }
+ }
+ else{
+ _secTimeout = snow + 1000;
+ }
+
+ _lastCheck = now;
+ return rc;
+}
+
+IPAddress DhcpClass::getLocalIp()
+{
+ return IPAddress(_dhcpLocalIp);
+}
+
+IPAddress DhcpClass::getSubnetMask()
+{
+ return IPAddress(_dhcpSubnetMask);
+}
+
+IPAddress DhcpClass::getGatewayIp()
+{
+ return IPAddress(_dhcpGatewayIp);
+}
+
+IPAddress DhcpClass::getDhcpServerIp()
+{
+ return IPAddress(_dhcpDhcpServerIp);
+}
+
+IPAddress DhcpClass::getDnsServerIp()
+{
+ return IPAddress(_dhcpDnsServerIp);
+}
+
+void DhcpClass::printByte(char * buf, uint8_t n ) {
+ char *str = &buf[1];
+ buf[0]='0';
+ do {
+ unsigned long m = n;
+ n /= 16;
+ char c = m - 16 * n;
+ *str-- = c < 10 ? c + '0' : c + 'A' - 10;
+ } while(n);
+}
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