A stack which works with or without an Mbed os library. Provides IPv4 or IPv6 with a full 1500 byte buffer.
Dependents: oldheating gps motorhome heating
arp/arp.c
- Committer:
- andrewboyson
- Date:
- 2018-12-05
- Revision:
- 94:e2973a2c488e
- Parent:
- 61:aad055f1b0d1
- Child:
- 136:8a65abb0dc63
File content as of revision 94:e2973a2c488e:
#include <stdint.h> #include <stdbool.h> #include "log.h" #include "action.h" #include "net.h" #include "eth.h" #include "mac.h" #include "dhcp.h" #include "ar4.h" #include "nr4.h" #include "ip4addr.h" #define REQUEST 1 #define REPLY 2 bool ArpTrace = false; uint32_t ArpAddressToResolve; bool ArpResolveRequestFlag = false; __packed struct header { int16_t hardwareType; //16.bit: (ar$hrd) Hardware address space (e.g., Ethernet, Packet Radio Net). Always 1. int16_t protocolType; //16.bit: (ar$pro) Protocol address space. For Ethernet hardware, this is from the set of type fields ether_typ$<protocol>. As held in eth.h, eg IPv4 = 0x8000. int8_t hardwareLength; // 8.bit: (ar$hln) byte length of each hardware address. Always 6 bytes. int8_t protocolLength; // 8.bit: (ar$pln) byte length of each protocol address. Always 4 bytes. int16_t opCode; //16.bit: (ar$op) opcode (ares_op$REQUEST = 1 | ares_op$REPLY = 2), high byte transmitted first. char senderHardwareAddress[6]; //nbytes: (ar$sha) Hardware address of sender of this packet, n from the ar$hln field. uint32_t senderProtocolAddress; //mbytes: (ar$spa) Protocol address of sender of this packet, m from the ar$pln field. char targetHardwareAddress[6]; //nbytes: (ar$tha) Hardware address of target of this packet (if known). uint32_t targetProtocolAddress; //mbytes: (ar$tpa) Protocol address of target. }; static void logHeader(struct header* pHeader) { if (NetTraceVerbose) { LogTime("ARP header\r\n"); if (NetToHost16(pHeader->hardwareType) == ETHERNET) Log (" hardwareType = ETHERNET\r\n"); else LogF(" hardwareType = %d\r\n", NetToHost16(pHeader->hardwareType)); Log (" protocolType = "); EthProtocolLog(pHeader->protocolType); Log("\r\n"); LogF(" hardwareLength = %d\r\n", pHeader->hardwareLength); LogF(" protocolLength = %d\r\n", pHeader->protocolLength); if (NetToHost16(pHeader->opCode) == REQUEST) Log (" opCode = REQUEST\r\n"); else if (NetToHost16(pHeader->opCode) == REPLY ) Log (" opCode = REPLY\r\n"); else LogF(" opCode = %d\r\n", NetToHost16(pHeader->opCode)); Log(" senderHardwareAddress = "); MacLog(pHeader->senderHardwareAddress); Log("\r\n"); Log(" senderProtocolAddress = "); Ip4AddressLog(pHeader->senderProtocolAddress); Log("\r\n"); Log(" targetHardwareAddress = "); MacLog(pHeader->targetHardwareAddress); Log("\r\n"); Log(" targetProtocolAddress = "); Ip4AddressLog(pHeader->targetProtocolAddress); Log("\r\n"); } else { Log("ARP header "); MacLog(pHeader->senderHardwareAddress); Log("=="); Ip4AddressLog(pHeader->senderProtocolAddress); Log(" >>> "); MacLog(pHeader->targetHardwareAddress); Log("=="); Ip4AddressLog(pHeader->targetProtocolAddress); Log("\r\n"); } } static struct header* pHeaderTrace; static void (*pTraceBack)(void); static void trace() { pTraceBack(); logHeader(pHeaderTrace); } int ArpHandleReceivedPacket(void (*traceback)(void), void* pPacketRx, int sizeRx, void* pPacketTx, int* pSizeTx) { pTraceBack = traceback; struct header* pHeaderRx = (struct header*)pPacketRx; struct header* pHeaderTx = (struct header*)pPacketTx; pHeaderTrace = pHeaderRx; int16_t hardwareType = NetToHost16(pHeaderRx->hardwareType); int16_t protocolType = NetToHost16(pHeaderRx->protocolType); int8_t hardwareLength = pHeaderRx->hardwareLength; int8_t protocolLength = pHeaderRx->protocolLength; int16_t opCode = NetToHost16(pHeaderRx->opCode); uint32_t targetProtocolAddress = pHeaderRx->targetProtocolAddress; if (hardwareType != ETHERNET ) return DO_NOTHING; //This is not ethernet if (protocolType != IPV4 ) return DO_NOTHING; //This is not IPv4 if (hardwareLength != 6 ) return DO_NOTHING; //This is not a MAC hardware address if (protocolLength != 4 ) return DO_NOTHING; //This is not an IPv4 IP address if (targetProtocolAddress != DhcpLocalIp ) return DO_NOTHING; //This packet was not addressed to us switch (opCode) { case REQUEST: if (ArpTrace) { if (NetTraceNewLine) Log("\r\n"); LogTime("ARP received request\r\n"); if (NetTraceStack) traceback(); logHeader(pHeaderRx); } pHeaderTx->hardwareType = NetToHost16(ETHERNET); pHeaderTx->protocolType = NetToHost16(IPV4); pHeaderTx->hardwareLength = 6; pHeaderTx->protocolLength = 4; pHeaderTx->opCode = NetToHost16(REPLY); MacCopy(pHeaderTx->targetHardwareAddress, pHeaderRx->senderHardwareAddress); pHeaderTx->targetProtocolAddress = pHeaderRx->senderProtocolAddress; MacCopy(pHeaderTx->senderHardwareAddress, MacLocal); pHeaderTx->senderProtocolAddress = DhcpLocalIp; *pSizeTx = sizeof(struct header); if (ArpTrace) logHeader(pHeaderTx); return ActionMakeFromDestAndTrace(UNICAST, ArpTrace && NetTraceStack); case REPLY: if (ArpTrace) { if (NetTraceNewLine) Log("\r\n"); LogTime("ARP received reply\r\n"); if (NetTraceStack) traceback(); logHeader(pHeaderRx); } Ar4AddIpRecord(trace, pHeaderRx->senderHardwareAddress, pHeaderRx->senderProtocolAddress); Nr4MakeRequestForNameFromIp(pHeaderRx->senderProtocolAddress); return DO_NOTHING; default: return DO_NOTHING; } } int ArpPollForPacketToSend(void* pPacketTx, int* pSizeTx) { if (!ArpResolveRequestFlag) return DO_NOTHING; ArpResolveRequestFlag = false; struct header* pHeaderTx = (struct header*)pPacketTx; pHeaderTx->hardwareType = NetToHost16(ETHERNET); pHeaderTx->protocolType = NetToHost16(IPV4); pHeaderTx->hardwareLength = 6; pHeaderTx->protocolLength = 4; pHeaderTx->opCode = NetToHost16(REQUEST); MacClear(pHeaderTx->targetHardwareAddress); pHeaderTx->targetProtocolAddress = ArpAddressToResolve; MacCopy (pHeaderTx->senderHardwareAddress, MacLocal); pHeaderTx->senderProtocolAddress = DhcpLocalIp; *pSizeTx = sizeof(struct header); if (ArpTrace) { if (NetTraceNewLine) Log("\r\n"); LogTime("ARP send request\r\n"); logHeader(pHeaderTx); } return ActionMakeFromDestAndTrace(BROADCAST, ArpTrace && NetTraceStack); }