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/ip4.c@172:9bc3c7b2cca1, 2020-12-16 (annotated)
- Committer:
- andrewboyson
- Date:
- Wed Dec 16 17:33:22 2020 +0000
- Revision:
- 172:9bc3c7b2cca1
- Parent:
- 160:6a1d1d368f80
- Child:
- 187:122fc1996c86
Modified name resolution to work with both IPv4 and IPv6. Before there were two independent modules.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
andrewboyson | 136:8a65abb0dc63 | 1 | |
andrewboyson | 61:aad055f1b0d1 | 2 | #include <stdint.h> |
andrewboyson | 61:aad055f1b0d1 | 3 | #include <stdbool.h> |
andrewboyson | 61:aad055f1b0d1 | 4 | |
andrewboyson | 43:bc028d5a6424 | 5 | #include "log.h" |
andrewboyson | 43:bc028d5a6424 | 6 | #include "net.h" |
andrewboyson | 43:bc028d5a6424 | 7 | #include "action.h" |
andrewboyson | 43:bc028d5a6424 | 8 | #include "icmp4.h" |
andrewboyson | 10:f0854784e960 | 9 | #include "udptcp4.h" |
andrewboyson | 48:952dddb74b8b | 10 | #include "ar4.h" |
andrewboyson | 172:9bc3c7b2cca1 | 11 | #include "nr.h" |
andrewboyson | 43:bc028d5a6424 | 12 | #include "dhcp.h" |
andrewboyson | 43:bc028d5a6424 | 13 | #include "eth.h" |
andrewboyson | 43:bc028d5a6424 | 14 | #include "ip.h" |
andrewboyson | 49:1a6336f2b3f9 | 15 | #include "ip4addr.h" |
andrewboyson | 136:8a65abb0dc63 | 16 | #include "ip4hdr.h" |
andrewboyson | 43:bc028d5a6424 | 17 | #include "ntp.h" |
andrewboyson | 43:bc028d5a6424 | 18 | #include "mac.h" |
andrewboyson | 142:a8c0890a58d1 | 19 | #include "restart.h" |
andrewboyson | 136:8a65abb0dc63 | 20 | #include "checksum.h" |
andrewboyson | 10:f0854784e960 | 21 | |
andrewboyson | 48:952dddb74b8b | 22 | bool Ip4Trace = true; |
andrewboyson | 10:f0854784e960 | 23 | |
andrewboyson | 53:77f8a49adf89 | 24 | #define OFF_LINK_TTL 64 |
andrewboyson | 53:77f8a49adf89 | 25 | |
andrewboyson | 136:8a65abb0dc63 | 26 | static void logHeader(char* pPacket) |
andrewboyson | 11:c051adb70c5a | 27 | { |
andrewboyson | 43:bc028d5a6424 | 28 | if (NetTraceVerbose) |
andrewboyson | 43:bc028d5a6424 | 29 | { |
andrewboyson | 44:83ce5ace337b | 30 | Log ("IP4 header\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 31 | LogF(" Version %d\r\n", Ip4HdrGetVersion (pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 32 | int headerLength = Ip4HdrGetHeaderLen (pPacket); |
andrewboyson | 43:bc028d5a6424 | 33 | LogF(" Header length %d\r\n", headerLength); |
andrewboyson | 136:8a65abb0dc63 | 34 | LogF(" Type of service %d\r\n", Ip4HdrGetTos (pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 35 | LogF(" Total length %d\r\n", Ip4HdrGetLength (pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 36 | LogF(" Identification %d\r\n", Ip4HdrGetId (pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 37 | if (Ip4HdrGetDontFrag(pPacket)) LogF(" Don't fragment\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 38 | else LogF(" Do fragment\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 39 | if (Ip4HdrGetMoreFrags(pPacket)) LogF(" More fragments\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 40 | else LogF(" No more fragments\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 41 | LogF(" Frag offset %d\r\n", Ip4HdrGetFragOffset(pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 42 | LogF(" Time to live %d\r\n", Ip4HdrGetTtl (pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 43 | LogF(" Protocol "); IpProtocolLog(Ip4HdrGetProtocol(pPacket)); Log("\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 44 | LogF(" Checksum (hex) %04hX\r\n", Ip4HdrGetChecksum(pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 45 | LogF(" Calculated (hex) %04hX\r\n", CheckSum(headerLength, pPacket)); |
andrewboyson | 136:8a65abb0dc63 | 46 | LogF(" Source IP "); Ip4AddressLog(Ip4HdrGetSrc(pPacket)); Log("\r\n"); |
andrewboyson | 136:8a65abb0dc63 | 47 | LogF(" Destination IP "); Ip4AddressLog(Ip4HdrGetDst(pPacket)); Log("\r\n"); |
andrewboyson | 43:bc028d5a6424 | 48 | } |
andrewboyson | 43:bc028d5a6424 | 49 | else |
andrewboyson | 43:bc028d5a6424 | 50 | { |
andrewboyson | 44:83ce5ace337b | 51 | Log ("IP4 header "); |
andrewboyson | 136:8a65abb0dc63 | 52 | IpProtocolLog(Ip4HdrGetProtocol(pPacket)); |
andrewboyson | 43:bc028d5a6424 | 53 | Log(" "); |
andrewboyson | 136:8a65abb0dc63 | 54 | Ip4AddressLog(Ip4HdrGetSrc(pPacket)); |
andrewboyson | 43:bc028d5a6424 | 55 | Log(" >>> "); |
andrewboyson | 136:8a65abb0dc63 | 56 | Ip4AddressLog(Ip4HdrGetDst(pPacket)); |
andrewboyson | 43:bc028d5a6424 | 57 | Log("\r\n"); |
andrewboyson | 43:bc028d5a6424 | 58 | } |
andrewboyson | 11:c051adb70c5a | 59 | } |
andrewboyson | 136:8a65abb0dc63 | 60 | static void makeHeader(char* pPacket, uint16_t totalLength, uint8_t ttl, uint8_t protocol, uint32_t srcIp, uint32_t dstIp) |
andrewboyson | 136:8a65abb0dc63 | 61 | { |
andrewboyson | 136:8a65abb0dc63 | 62 | static uint16_t id = 0; |
andrewboyson | 136:8a65abb0dc63 | 63 | Ip4HdrSetVersion (pPacket, 4 ); |
andrewboyson | 136:8a65abb0dc63 | 64 | Ip4HdrSetHeaderLen(pPacket, IP4_HEADER_LENGTH); |
andrewboyson | 136:8a65abb0dc63 | 65 | Ip4HdrSetTos (pPacket, 0 ); |
andrewboyson | 136:8a65abb0dc63 | 66 | Ip4HdrSetLength (pPacket, totalLength ); |
andrewboyson | 136:8a65abb0dc63 | 67 | Ip4HdrSetId (pPacket, id++ ); //Used by the recipient for collating packets fragmented in transit; unique per packet sent |
andrewboyson | 136:8a65abb0dc63 | 68 | Ip4HdrSetFragInfo (pPacket, 0 ); //No flags and no offset |
andrewboyson | 136:8a65abb0dc63 | 69 | Ip4HdrSetTtl (pPacket, ttl ); |
andrewboyson | 136:8a65abb0dc63 | 70 | Ip4HdrSetProtocol (pPacket, protocol ); |
andrewboyson | 136:8a65abb0dc63 | 71 | Ip4HdrSetSrc (pPacket, srcIp ); |
andrewboyson | 136:8a65abb0dc63 | 72 | Ip4HdrSetDst (pPacket, dstIp ); |
andrewboyson | 136:8a65abb0dc63 | 73 | Ip4HdrSetChecksum (pPacket, 0 ); |
andrewboyson | 136:8a65abb0dc63 | 74 | uint16_t checksum = CheckSum(IP4_HEADER_LENGTH, pPacket); |
andrewboyson | 136:8a65abb0dc63 | 75 | Ip4HdrSetChecksum (pPacket, checksum ); |
andrewboyson | 136:8a65abb0dc63 | 76 | } |
andrewboyson | 136:8a65abb0dc63 | 77 | static char* traceHeader; |
andrewboyson | 37:793b39683406 | 78 | static void (*pTraceBack)(void); |
andrewboyson | 37:793b39683406 | 79 | static void trace() |
andrewboyson | 10:f0854784e960 | 80 | { |
andrewboyson | 37:793b39683406 | 81 | pTraceBack(); |
andrewboyson | 136:8a65abb0dc63 | 82 | logHeader(traceHeader); |
andrewboyson | 37:793b39683406 | 83 | } |
andrewboyson | 136:8a65abb0dc63 | 84 | |
andrewboyson | 136:8a65abb0dc63 | 85 | int Ip4HandleReceivedPacket(void (*traceback)(void), char* pPacketRx, int sizeRx, char* pPacketTx, int* pSizeTx, char* macRemote) |
andrewboyson | 37:793b39683406 | 86 | { |
andrewboyson | 142:a8c0890a58d1 | 87 | int lastRestartPoint = RestartPoint; |
andrewboyson | 142:a8c0890a58d1 | 88 | RestartPoint = FAULT_POINT_Ip4HandleReceivedPacket; |
andrewboyson | 136:8a65abb0dc63 | 89 | |
andrewboyson | 136:8a65abb0dc63 | 90 | traceHeader = pPacketRx; |
andrewboyson | 37:793b39683406 | 91 | pTraceBack = traceback; |
andrewboyson | 136:8a65abb0dc63 | 92 | |
andrewboyson | 136:8a65abb0dc63 | 93 | int headerLengthRx = Ip4HdrGetHeaderLen(pPacketRx); |
andrewboyson | 136:8a65abb0dc63 | 94 | uint16_t totalLengthRx = Ip4HdrGetLength (pPacketRx); |
andrewboyson | 136:8a65abb0dc63 | 95 | uint8_t protocol = Ip4HdrGetProtocol (pPacketRx); |
andrewboyson | 136:8a65abb0dc63 | 96 | uint32_t srcIp = Ip4HdrGetSrc (pPacketRx); |
andrewboyson | 136:8a65abb0dc63 | 97 | uint32_t dstIp = Ip4HdrGetDst (pPacketRx); |
andrewboyson | 59:e0e556c8bd46 | 98 | |
andrewboyson | 136:8a65abb0dc63 | 99 | char* pDataRx = pPacketRx + headerLengthRx; |
andrewboyson | 136:8a65abb0dc63 | 100 | char* pDataTx = pPacketTx + IP4_HEADER_LENGTH; |
andrewboyson | 136:8a65abb0dc63 | 101 | |
andrewboyson | 136:8a65abb0dc63 | 102 | if (sizeRx > totalLengthRx) sizeRx = totalLengthRx; |
andrewboyson | 136:8a65abb0dc63 | 103 | int dataLengthRx = sizeRx - headerLengthRx; |
andrewboyson | 136:8a65abb0dc63 | 104 | int dataLengthTx = *pSizeTx - IP4_HEADER_LENGTH; |
andrewboyson | 136:8a65abb0dc63 | 105 | |
andrewboyson | 61:aad055f1b0d1 | 106 | bool isMe = dstIp == DhcpLocalIp; |
andrewboyson | 61:aad055f1b0d1 | 107 | bool isLocalBroadcast = dstIp == (DhcpLocalIp | 0xFF000000); // dstIp == 192.168.1.255; '|' is lower precendence than '==' |
andrewboyson | 61:aad055f1b0d1 | 108 | bool isBroadcast = dstIp == IP4_BROADCAST_ADDRESS; // dstIp == 255.255.255.255 |
andrewboyson | 136:8a65abb0dc63 | 109 | bool isMulticast = (dstIp & 0xE0) == 0xE0; // 224.x.x.x == 1110 0000 == E0.xx.xx.xx == xx.xx.xx.E0 in little endian |
andrewboyson | 136:8a65abb0dc63 | 110 | |
andrewboyson | 15:6ca6778168b1 | 111 | bool doIt = isMe || isLocalBroadcast || isBroadcast || isMulticast; |
andrewboyson | 15:6ca6778168b1 | 112 | if (!doIt) |
andrewboyson | 15:6ca6778168b1 | 113 | { |
andrewboyson | 160:6a1d1d368f80 | 114 | if (Ip4Trace) |
andrewboyson | 15:6ca6778168b1 | 115 | { |
andrewboyson | 136:8a65abb0dc63 | 116 | LogTimeF("IP4 filtered out ip "); Ip4AddressLog(dstIp); |
andrewboyson | 47:73af5c0b0dc2 | 117 | Log(" from "); |
andrewboyson | 47:73af5c0b0dc2 | 118 | Ip4AddressLog(srcIp); |
andrewboyson | 47:73af5c0b0dc2 | 119 | Log("\r\n"); |
andrewboyson | 15:6ca6778168b1 | 120 | } |
andrewboyson | 142:a8c0890a58d1 | 121 | RestartPoint = lastRestartPoint; |
andrewboyson | 15:6ca6778168b1 | 122 | return DO_NOTHING; |
andrewboyson | 15:6ca6778168b1 | 123 | } |
andrewboyson | 136:8a65abb0dc63 | 124 | |
andrewboyson | 74:c3756bfa960e | 125 | int remArIndex = Ar4AddIpRecord(trace, macRemote, srcIp); |
andrewboyson | 172:9bc3c7b2cca1 | 126 | NrMakeRequestForNameFromAddress4(srcIp); |
andrewboyson | 136:8a65abb0dc63 | 127 | |
andrewboyson | 10:f0854784e960 | 128 | int action = DO_NOTHING; |
andrewboyson | 10:f0854784e960 | 129 | switch (protocol) |
andrewboyson | 10:f0854784e960 | 130 | { |
andrewboyson | 97:d91f7db00235 | 131 | case ICMP: action = Icmp4HandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx, &srcIp, &dstIp); break; |
andrewboyson | 97:d91f7db00235 | 132 | case IGMP: break; |
andrewboyson | 97:d91f7db00235 | 133 | case UDP: action = Udp4HandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx, &srcIp, &dstIp); break; |
andrewboyson | 74:c3756bfa960e | 134 | case TCP: action = Tcp4HandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx, &srcIp, &dstIp, remArIndex); break; |
andrewboyson | 97:d91f7db00235 | 135 | case IP6IN4: break; |
andrewboyson | 10:f0854784e960 | 136 | default: |
andrewboyson | 136:8a65abb0dc63 | 137 | LogTimeF("IP4 received packet unknown protocol %d\r\n", protocol); |
andrewboyson | 142:a8c0890a58d1 | 138 | RestartPoint = lastRestartPoint; |
andrewboyson | 10:f0854784e960 | 139 | return DO_NOTHING; |
andrewboyson | 10:f0854784e960 | 140 | } |
andrewboyson | 86:55bc5ddac16c | 141 | if (!action) |
andrewboyson | 86:55bc5ddac16c | 142 | { |
andrewboyson | 142:a8c0890a58d1 | 143 | RestartPoint = lastRestartPoint; |
andrewboyson | 86:55bc5ddac16c | 144 | return DO_NOTHING; |
andrewboyson | 86:55bc5ddac16c | 145 | } |
andrewboyson | 136:8a65abb0dc63 | 146 | |
andrewboyson | 136:8a65abb0dc63 | 147 | uint8_t ttl = 0; |
andrewboyson | 53:77f8a49adf89 | 148 | if (DhcpIpNeedsToBeRouted(dstIp)) |
andrewboyson | 53:77f8a49adf89 | 149 | { |
andrewboyson | 116:60521b29e4c9 | 150 | Ar4IpToMac(DhcpRouterIp, macRemote); //Send back to the router |
andrewboyson | 53:77f8a49adf89 | 151 | ttl = OFF_LINK_TTL; |
andrewboyson | 53:77f8a49adf89 | 152 | } |
andrewboyson | 53:77f8a49adf89 | 153 | else |
andrewboyson | 53:77f8a49adf89 | 154 | { |
andrewboyson | 53:77f8a49adf89 | 155 | ttl = 255; |
andrewboyson | 53:77f8a49adf89 | 156 | } |
andrewboyson | 59:e0e556c8bd46 | 157 | |
andrewboyson | 136:8a65abb0dc63 | 158 | *pSizeTx = IP4_HEADER_LENGTH + dataLengthTx; |
andrewboyson | 53:77f8a49adf89 | 159 | |
andrewboyson | 136:8a65abb0dc63 | 160 | makeHeader(pPacketTx, *pSizeTx, ttl, protocol, srcIp, dstIp); |
andrewboyson | 10:f0854784e960 | 161 | |
andrewboyson | 136:8a65abb0dc63 | 162 | if (ActionGetTracePart(action)) logHeader(pPacketTx); |
andrewboyson | 37:793b39683406 | 163 | |
andrewboyson | 142:a8c0890a58d1 | 164 | RestartPoint = lastRestartPoint; |
andrewboyson | 10:f0854784e960 | 165 | return action; |
andrewboyson | 10:f0854784e960 | 166 | } |
andrewboyson | 136:8a65abb0dc63 | 167 | int Ip4PollForPacketToSend(char* pPacket, int* pSize, char* pDstMac) |
andrewboyson | 136:8a65abb0dc63 | 168 | { |
andrewboyson | 136:8a65abb0dc63 | 169 | char* pData = pPacket + IP4_HEADER_LENGTH; |
andrewboyson | 136:8a65abb0dc63 | 170 | int dataLength = *pSize - IP4_HEADER_LENGTH; |
andrewboyson | 136:8a65abb0dc63 | 171 | |
andrewboyson | 136:8a65abb0dc63 | 172 | uint8_t protocol = 0; |
andrewboyson | 136:8a65abb0dc63 | 173 | uint32_t srcIp = 0; |
andrewboyson | 136:8a65abb0dc63 | 174 | uint32_t dstIp = 0; |
andrewboyson | 136:8a65abb0dc63 | 175 | int action = DO_NOTHING; |
andrewboyson | 71:736a5747ade1 | 176 | if (!action) { action = Udp4PollForPacketToSend(pData, &dataLength, &srcIp, &dstIp); protocol = UDP; } |
andrewboyson | 71:736a5747ade1 | 177 | if (!action) { action = Tcp4PollForPacketToSend(pData, &dataLength, &srcIp, &dstIp); protocol = TCP; } |
andrewboyson | 11:c051adb70c5a | 178 | if (!action) return DO_NOTHING; |
andrewboyson | 42:222a4f45f916 | 179 | int dest = ActionGetDestPart(action); |
andrewboyson | 136:8a65abb0dc63 | 180 | uint8_t ttl = 0; |
andrewboyson | 42:222a4f45f916 | 181 | switch (dest) |
andrewboyson | 11:c051adb70c5a | 182 | { |
andrewboyson | 11:c051adb70c5a | 183 | case UNICAST: |
andrewboyson | 11:c051adb70c5a | 184 | case UNICAST_DNS: |
andrewboyson | 11:c051adb70c5a | 185 | case UNICAST_DHCP: |
andrewboyson | 22:914b970356f0 | 186 | case UNICAST_NTP: |
andrewboyson | 57:e0fb648acf48 | 187 | case UNICAST_TFTP: |
andrewboyson | 53:77f8a49adf89 | 188 | if (DhcpIpNeedsToBeRouted(dstIp)) |
andrewboyson | 53:77f8a49adf89 | 189 | { |
andrewboyson | 116:60521b29e4c9 | 190 | Ar4IpToMac(DhcpRouterIp, pDstMac); //send via router |
andrewboyson | 53:77f8a49adf89 | 191 | ttl = OFF_LINK_TTL; |
andrewboyson | 53:77f8a49adf89 | 192 | } |
andrewboyson | 53:77f8a49adf89 | 193 | else |
andrewboyson | 53:77f8a49adf89 | 194 | { |
andrewboyson | 116:60521b29e4c9 | 195 | Ar4IpToMac(dstIp, pDstMac); //Send direct |
andrewboyson | 53:77f8a49adf89 | 196 | ttl = 255; |
andrewboyson | 53:77f8a49adf89 | 197 | } |
andrewboyson | 11:c051adb70c5a | 198 | break; |
andrewboyson | 42:222a4f45f916 | 199 | case MULTICAST_NODE: |
andrewboyson | 42:222a4f45f916 | 200 | case MULTICAST_ROUTER: |
andrewboyson | 42:222a4f45f916 | 201 | case MULTICAST_MDNS: |
andrewboyson | 42:222a4f45f916 | 202 | case MULTICAST_LLMNR: |
andrewboyson | 112:f8694d0b8858 | 203 | case MULTICAST_NTP: |
andrewboyson | 22:914b970356f0 | 204 | case BROADCAST: |
andrewboyson | 53:77f8a49adf89 | 205 | ttl = 255; |
andrewboyson | 22:914b970356f0 | 206 | break; |
andrewboyson | 22:914b970356f0 | 207 | default: |
andrewboyson | 42:222a4f45f916 | 208 | LogTimeF("Ip4PollForPacketToSend - undefined destination %d\r\n", dest); |
andrewboyson | 53:77f8a49adf89 | 209 | return DO_NOTHING; |
andrewboyson | 11:c051adb70c5a | 210 | } |
andrewboyson | 10:f0854784e960 | 211 | |
andrewboyson | 136:8a65abb0dc63 | 212 | *pSize = IP4_HEADER_LENGTH + dataLength; |
andrewboyson | 136:8a65abb0dc63 | 213 | |
andrewboyson | 136:8a65abb0dc63 | 214 | makeHeader(pPacket, *pSize, ttl, protocol, srcIp, dstIp); |
andrewboyson | 59:e0e556c8bd46 | 215 | |
andrewboyson | 136:8a65abb0dc63 | 216 | if (ActionGetTracePart(action)) logHeader(pPacket); |
andrewboyson | 37:793b39683406 | 217 | |
andrewboyson | 10:f0854784e960 | 218 | return action; |
andrewboyson | 10:f0854784e960 | 219 | } |