Andrew Boyson / net

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

ip4/icmp/icmp4.c@61:aad055f1b0d1, 2018-01-11 (annotated)

Committer:
andrewboyson
Date:
Thu Jan 11 17:38:21 2018 +0000
Revision:
61:aad055f1b0d1
Parent:
ip4/icmp/icmp4.cpp@59:e0e556c8bd46
Child:
136:8a65abb0dc63
Removed dependence on Mbed OS

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 61:aad055f1b0d1 1 #include <stdint.h>
andrewboyson 61:aad055f1b0d1 2
andrewboyson 43:bc028d5a6424 3 #include "log.h"
andrewboyson 43:bc028d5a6424 4 #include "net.h"
andrewboyson 43:bc028d5a6424 5 #include "action.h"
andrewboyson 43:bc028d5a6424 6 #include "ip4.h"
andrewboyson 43:bc028d5a6424 7 #include "dhcp.h"
andrewboyson 43:bc028d5a6424 8 #include "echo4.h"
andrewboyson 43:bc028d5a6424 9
andrewboyson 43:bc028d5a6424 10 #define ECHO_REPLY 0
andrewboyson 43:bc028d5a6424 11 #define UNREACHABLE 3
andrewboyson 43:bc028d5a6424 12 #define REDIRECT 5
andrewboyson 43:bc028d5a6424 13 #define ECHO_REQUEST 8
andrewboyson 43:bc028d5a6424 14
andrewboyson 43:bc028d5a6424 15 __packed struct header
andrewboyson 43:bc028d5a6424 16 {
andrewboyson 43:bc028d5a6424 17 uint8_t type;
andrewboyson 43:bc028d5a6424 18 uint8_t code;
andrewboyson 43:bc028d5a6424 19 uint16_t checksum;
andrewboyson 43:bc028d5a6424 20 };
andrewboyson 43:bc028d5a6424 21 static uint8_t type;
andrewboyson 43:bc028d5a6424 22 static uint8_t code;
andrewboyson 43:bc028d5a6424 23 static uint16_t checksum;
andrewboyson 43:bc028d5a6424 24 static uint16_t calculated;
andrewboyson 43:bc028d5a6424 25
andrewboyson 47:73af5c0b0dc2 26 static void logType(uint16_t type)
andrewboyson 43:bc028d5a6424 27 {
andrewboyson 43:bc028d5a6424 28 switch (type)
andrewboyson 43:bc028d5a6424 29 {
andrewboyson 47:73af5c0b0dc2 30 case ECHO_REPLY: Log ("Echo Reply" ); break;
andrewboyson 47:73af5c0b0dc2 31 case ECHO_REQUEST: Log ("Echo Request" ); break;
andrewboyson 47:73af5c0b0dc2 32 default: LogF("Unknown type %d", type); break;
andrewboyson 43:bc028d5a6424 33 }
andrewboyson 43:bc028d5a6424 34 }
andrewboyson 43:bc028d5a6424 35 static void logHeader()
andrewboyson 47:73af5c0b0dc2 36 {
andrewboyson 43:bc028d5a6424 37 if (NetTraceVerbose)
andrewboyson 43:bc028d5a6424 38 {
andrewboyson 43:bc028d5a6424 39 Log ("ICMP4 header\r\n");
andrewboyson 47:73af5c0b0dc2 40 LogF(" Type "); logType(type); Log("\r\n");
andrewboyson 43:bc028d5a6424 41 LogF(" Code %u\r\n", code);
andrewboyson 43:bc028d5a6424 42 LogF(" Checksum (hex) %04hX\r\n", checksum);
andrewboyson 43:bc028d5a6424 43 LogF(" Calculated %04hX\r\n", calculated);
andrewboyson 43:bc028d5a6424 44 }
andrewboyson 43:bc028d5a6424 45 else
andrewboyson 43:bc028d5a6424 46 {
andrewboyson 43:bc028d5a6424 47 Log("ICMP4 header ");
andrewboyson 47:73af5c0b0dc2 48 logType(type);
andrewboyson 43:bc028d5a6424 49 Log("\r\n");
andrewboyson 43:bc028d5a6424 50 }
andrewboyson 43:bc028d5a6424 51 }
andrewboyson 43:bc028d5a6424 52 static void readHeader(void* pPacket, int size)
andrewboyson 43:bc028d5a6424 53 {
andrewboyson 61:aad055f1b0d1 54 struct header* pHeader = (struct header*)pPacket;
andrewboyson 43:bc028d5a6424 55 type = pHeader->type;
andrewboyson 43:bc028d5a6424 56 code = pHeader->code;
andrewboyson 43:bc028d5a6424 57 checksum = NetToHost16(pHeader->checksum);
andrewboyson 43:bc028d5a6424 58 calculated = NetCheckSum(size, pPacket);
andrewboyson 43:bc028d5a6424 59 }
andrewboyson 43:bc028d5a6424 60 static void writeHeader(void* pPacket, int size)
andrewboyson 43:bc028d5a6424 61 {
andrewboyson 61:aad055f1b0d1 62 struct header* pHeader = (struct header*)pPacket;
andrewboyson 43:bc028d5a6424 63 pHeader->type = type;
andrewboyson 43:bc028d5a6424 64 pHeader->code = code;
andrewboyson 43:bc028d5a6424 65 pHeader->checksum = 0;
andrewboyson 43:bc028d5a6424 66 pHeader->checksum = NetCheckSum(size, pPacket);
andrewboyson 43:bc028d5a6424 67 calculated = 0;
andrewboyson 43:bc028d5a6424 68 }
andrewboyson 43:bc028d5a6424 69 static void (*pTraceBack)(void);
andrewboyson 43:bc028d5a6424 70 static void trace()
andrewboyson 43:bc028d5a6424 71 {
andrewboyson 43:bc028d5a6424 72 pTraceBack();
andrewboyson 43:bc028d5a6424 73 logHeader();
andrewboyson 43:bc028d5a6424 74 }
andrewboyson 59:e0e556c8bd46 75 int Icmp4HandleReceivedPacket(void (*traceback)(void), void* pPacketRx, int sizeRx, void* pPacketTx, int* pSizeTx, uint32_t* pSrcIp, uint32_t* pDstIp)
andrewboyson 43:bc028d5a6424 76 {
andrewboyson 43:bc028d5a6424 77 pTraceBack = traceback;
andrewboyson 43:bc028d5a6424 78
andrewboyson 59:e0e556c8bd46 79 readHeader(pPacketRx, sizeRx);
andrewboyson 59:e0e556c8bd46 80
andrewboyson 61:aad055f1b0d1 81 int dataLengthRx = sizeRx - sizeof(struct header);
andrewboyson 61:aad055f1b0d1 82 int dataLengthTx = *pSizeTx - sizeof(struct header);
andrewboyson 61:aad055f1b0d1 83 char* pPayloadRx = (char*)pPacketRx + sizeof(struct header);
andrewboyson 61:aad055f1b0d1 84 char* pPayloadTx = (char*)pPacketTx + sizeof(struct header);
andrewboyson 43:bc028d5a6424 85
andrewboyson 43:bc028d5a6424 86 int action = DO_NOTHING;
andrewboyson 43:bc028d5a6424 87 switch (type)
andrewboyson 43:bc028d5a6424 88 {
andrewboyson 43:bc028d5a6424 89 case ECHO_REQUEST:
andrewboyson 59:e0e556c8bd46 90 action = Echo4HandleRequest(trace, &type, &code, pPayloadRx, dataLengthRx, pPayloadTx, &dataLengthTx);
andrewboyson 43:bc028d5a6424 91 break;
andrewboyson 43:bc028d5a6424 92 case UNREACHABLE:
andrewboyson 43:bc028d5a6424 93 return DO_NOTHING;
andrewboyson 43:bc028d5a6424 94 case REDIRECT:
andrewboyson 43:bc028d5a6424 95 return DO_NOTHING;
andrewboyson 43:bc028d5a6424 96 default:
andrewboyson 43:bc028d5a6424 97 LogTimeF("ICMP4 packet type %d unknown\r\n", type);
andrewboyson 43:bc028d5a6424 98 return DO_NOTHING;
andrewboyson 43:bc028d5a6424 99 }
andrewboyson 43:bc028d5a6424 100 if (!action) return DO_NOTHING;
andrewboyson 43:bc028d5a6424 101
andrewboyson 43:bc028d5a6424 102 *pDstIp = *pSrcIp;
andrewboyson 43:bc028d5a6424 103 *pSrcIp = DhcpLocalIp;
andrewboyson 43:bc028d5a6424 104
andrewboyson 61:aad055f1b0d1 105 *pSizeTx = sizeof(struct header) + dataLengthTx;
andrewboyson 43:bc028d5a6424 106
andrewboyson 59:e0e556c8bd46 107 writeHeader(pPacketTx, *pSizeTx);
andrewboyson 43:bc028d5a6424 108
andrewboyson 43:bc028d5a6424 109 if (ActionGetTracePart(action)) logHeader();
andrewboyson 43:bc028d5a6424 110
andrewboyson 43:bc028d5a6424 111 return action;
andrewboyson 43:bc028d5a6424 112 }