Andrew Boyson / net

A stack which works with or without an Mbed os library. Provides IPv4 or IPv6 with a full 1500 byte buffer.

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udp/dhcp/dhcp.c@128:79052cb4a41c, 2019-03-11 (annotated)

Committer:
andrewboyson
Date:
Mon Mar 11 16:42:45 2019 +0000
Revision:
128:79052cb4a41c
Parent:
119:8e1a7805b801
Child:
132:db2174b36a6d
Tidied up the DNS label module and removed some declarations that had not left room for the terminating null.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 61:aad055f1b0d1 1 #include <stdint.h>
andrewboyson 61:aad055f1b0d1 2 #include <stdbool.h>
andrewboyson 61:aad055f1b0d1 3 #include <string.h>
andrewboyson 61:aad055f1b0d1 4
andrewboyson 128:79052cb4a41c 5 #include "log.h"
andrewboyson 128:79052cb4a41c 6 #include "mstimer.h"
andrewboyson 128:79052cb4a41c 7 #include "net.h"
andrewboyson 128:79052cb4a41c 8 #include "action.h"
andrewboyson 128:79052cb4a41c 9 #include "eth.h"
andrewboyson 128:79052cb4a41c 10 #include "ip4addr.h"
andrewboyson 128:79052cb4a41c 11 #include "mac.h"
andrewboyson 128:79052cb4a41c 12 #include "udp.h"
andrewboyson 128:79052cb4a41c 13 #include "dnslabel.h"
andrewboyson 10:f0854784e960 14
andrewboyson 37:793b39683406 15 bool DhcpTrace = false;
andrewboyson 10:f0854784e960 16
andrewboyson 10:f0854784e960 17 #define REQUEST 1
andrewboyson 10:f0854784e960 18 #define REPLY 2
andrewboyson 10:f0854784e960 19
andrewboyson 10:f0854784e960 20 #define DHCPDISCOVER 1
andrewboyson 10:f0854784e960 21 #define DHCPOFFER 2
andrewboyson 10:f0854784e960 22 #define DHCPREQUEST 3
andrewboyson 10:f0854784e960 23 #define DHCPDECLINE 4
andrewboyson 10:f0854784e960 24 #define DHCPACK 5
andrewboyson 10:f0854784e960 25 #define DHCPNAK 6
andrewboyson 10:f0854784e960 26 #define DHCPRELEASE 7
andrewboyson 10:f0854784e960 27 #define DHCPINFORM 8
andrewboyson 10:f0854784e960 28
andrewboyson 10:f0854784e960 29 #define ID 75648
andrewboyson 10:f0854784e960 30 #define COOKIE 0x63825363
andrewboyson 10:f0854784e960 31 #define HEADER_LENGTH 240
andrewboyson 10:f0854784e960 32
andrewboyson 10:f0854784e960 33 __packed struct header
andrewboyson 10:f0854784e960 34 {
andrewboyson 10:f0854784e960 35 uint8_t op;
andrewboyson 10:f0854784e960 36 uint8_t htype;
andrewboyson 10:f0854784e960 37 uint8_t hlen;
andrewboyson 10:f0854784e960 38 uint8_t hops;
andrewboyson 10:f0854784e960 39
andrewboyson 10:f0854784e960 40 uint32_t xid;
andrewboyson 10:f0854784e960 41
andrewboyson 10:f0854784e960 42 uint16_t secs;
andrewboyson 10:f0854784e960 43 uint16_t flags;
andrewboyson 10:f0854784e960 44
andrewboyson 10:f0854784e960 45 uint32_t ciaddr;
andrewboyson 10:f0854784e960 46 uint32_t yiaddr;
andrewboyson 10:f0854784e960 47 uint32_t siaddr;
andrewboyson 10:f0854784e960 48 uint32_t giaddr;
andrewboyson 10:f0854784e960 49
andrewboyson 10:f0854784e960 50 uint8_t chaddr[16];
andrewboyson 10:f0854784e960 51
andrewboyson 10:f0854784e960 52 char legacy[192];
andrewboyson 10:f0854784e960 53
andrewboyson 10:f0854784e960 54 uint32_t cookie;
andrewboyson 10:f0854784e960 55 };
andrewboyson 10:f0854784e960 56
andrewboyson 116:60521b29e4c9 57 #define MAX_REPEAT_DELAY_TIME_MS 60000
andrewboyson 119:8e1a7805b801 58 #define MIN_REPEAT_DELAY_TIME_MS 900
andrewboyson 119:8e1a7805b801 59 static uint32_t repeatDelayMsTimer = (uint32_t)-MIN_REPEAT_DELAY_TIME_MS; //Initial value ensures no delay at startup
andrewboyson 119:8e1a7805b801 60 static uint32_t delayMs = MIN_REPEAT_DELAY_TIME_MS; //Doubles on failure up to max; reset to min whenever an IP address request has been acknowledged
andrewboyson 116:60521b29e4c9 61
andrewboyson 119:8e1a7805b801 62 static uint32_t elapsedLifeMsTimer = 0; //Started whenever an IP address request has been acknowledged
andrewboyson 93:580fc113d9e9 63
andrewboyson 93:580fc113d9e9 64 uint32_t DhcpGetElapsedLife()
andrewboyson 10:f0854784e960 65 {
andrewboyson 119:8e1a7805b801 66 if (!elapsedLifeMsTimer) return 0;
andrewboyson 119:8e1a7805b801 67 return (MsTimerCount - elapsedLifeMsTimer) / 1000;
andrewboyson 10:f0854784e960 68 }
andrewboyson 10:f0854784e960 69
andrewboyson 10:f0854784e960 70 static uint8_t dhcpMessageType = 0;
andrewboyson 10:f0854784e960 71 uint32_t DhcpLeaseTime = 0;
andrewboyson 116:60521b29e4c9 72 uint32_t DhcpServerIp = 0;
andrewboyson 116:60521b29e4c9 73 uint32_t DhcpRouterIp = 0;
andrewboyson 10:f0854784e960 74 uint32_t DhcpSubnetMask = 0;
andrewboyson 116:60521b29e4c9 75 uint32_t DhcpNtpIp = 0;
andrewboyson 10:f0854784e960 76 uint32_t DhcpRenewalT1 = 0;
andrewboyson 10:f0854784e960 77 uint32_t DhcpRenewalT2 = 0;
andrewboyson 10:f0854784e960 78 uint32_t DhcpBroadcastIp = 0;
andrewboyson 10:f0854784e960 79 uint32_t DhcpLocalIp = 0;
andrewboyson 116:60521b29e4c9 80 uint32_t DhcpDnsServerIp = 0;
andrewboyson 128:79052cb4a41c 81 char DhcpDomainName[DNS_MAX_LABEL_LENGTH+1];
andrewboyson 128:79052cb4a41c 82 char DhcpHostName [DNS_MAX_LABEL_LENGTH+1];
andrewboyson 44:83ce5ace337b 83
andrewboyson 44:83ce5ace337b 84 bool DhcpIpNeedsToBeRouted(uint32_t ip)
andrewboyson 44:83ce5ace337b 85 {
andrewboyson 44:83ce5ace337b 86 return ip & DhcpSubnetMask != DhcpBroadcastIp & DhcpSubnetMask;
andrewboyson 44:83ce5ace337b 87 }
andrewboyson 44:83ce5ace337b 88
andrewboyson 10:f0854784e960 89 static uint32_t readOption32(char** pp)
andrewboyson 10:f0854784e960 90 {
andrewboyson 10:f0854784e960 91 uint32_t value = 0;
andrewboyson 10:f0854784e960 92 char* p = *pp;
andrewboyson 10:f0854784e960 93 int len = *++p;
andrewboyson 10:f0854784e960 94 if (len >= 4)
andrewboyson 10:f0854784e960 95 {
andrewboyson 10:f0854784e960 96 value = *++p << 24;
andrewboyson 10:f0854784e960 97 value |= *++p << 16;
andrewboyson 10:f0854784e960 98 value |= *++p << 8;
andrewboyson 10:f0854784e960 99 value |= *++p << 0;
andrewboyson 10:f0854784e960 100 }
andrewboyson 10:f0854784e960 101 *pp += len + 1;
andrewboyson 10:f0854784e960 102 return value;
andrewboyson 10:f0854784e960 103 }
andrewboyson 10:f0854784e960 104 static uint32_t readIp(char** pp)
andrewboyson 10:f0854784e960 105 {
andrewboyson 10:f0854784e960 106 uint32_t value = 0;
andrewboyson 10:f0854784e960 107 char* p = *pp;
andrewboyson 10:f0854784e960 108 int len = *++p;
andrewboyson 10:f0854784e960 109 if (len >= 4)
andrewboyson 10:f0854784e960 110 {
andrewboyson 10:f0854784e960 111 value = *++p << 0;
andrewboyson 10:f0854784e960 112 value |= *++p << 8;
andrewboyson 10:f0854784e960 113 value |= *++p << 16;
andrewboyson 10:f0854784e960 114 value |= *++p << 24;
andrewboyson 10:f0854784e960 115 }
andrewboyson 10:f0854784e960 116 *pp += len + 1;
andrewboyson 10:f0854784e960 117 return value;
andrewboyson 10:f0854784e960 118 }
andrewboyson 10:f0854784e960 119 static void readString(char** pp, char* pText)
andrewboyson 10:f0854784e960 120 {
andrewboyson 10:f0854784e960 121 char* p = *pp;
andrewboyson 10:f0854784e960 122 int len = *++p;
andrewboyson 10:f0854784e960 123 for (int i = 0; i < len; i++) pText[i] = *++p;
andrewboyson 10:f0854784e960 124 *pp += len + 1;
andrewboyson 10:f0854784e960 125 }
andrewboyson 10:f0854784e960 126 static void readOptions(int size, char * pOptions)
andrewboyson 10:f0854784e960 127 {
andrewboyson 10:f0854784e960 128 int len = 0;
andrewboyson 10:f0854784e960 129 char* p = pOptions;
andrewboyson 10:f0854784e960 130 char* pE = pOptions + size;
andrewboyson 10:f0854784e960 131 while( p < pE)
andrewboyson 10:f0854784e960 132 {
andrewboyson 10:f0854784e960 133 switch (*p)
andrewboyson 10:f0854784e960 134 {
andrewboyson 10:f0854784e960 135 case 0: break; //NOP
andrewboyson 10:f0854784e960 136 case 255: return; //End of options
andrewboyson 10:f0854784e960 137 case 1: DhcpSubnetMask = readIp(&p); break; //Subnet Mask
andrewboyson 116:60521b29e4c9 138 case 3: DhcpRouterIp = readIp(&p); break; //Router
andrewboyson 116:60521b29e4c9 139 case 6: DhcpDnsServerIp = readIp(&p); break; //DNS server
andrewboyson 10:f0854784e960 140 case 12: readString(&p, DhcpHostName); break; //Host name
andrewboyson 10:f0854784e960 141 case 15: readString(&p, DhcpDomainName); break; //Domain name
andrewboyson 10:f0854784e960 142 case 19: len = *++p; p+= len; break; //IP forwarding yes/no
andrewboyson 10:f0854784e960 143 case 28: DhcpBroadcastIp = readIp(&p); break; //Broadcast IP
andrewboyson 116:60521b29e4c9 144 case 42: DhcpNtpIp = readIp(&p); break; //NTP
andrewboyson 10:f0854784e960 145 case 44: len = *++p; p+= len; break; //NetBIOS name server
andrewboyson 10:f0854784e960 146 case 45: len = *++p; p+= len; break; //NetBIOS datagram server
andrewboyson 10:f0854784e960 147 case 46: len = *++p; p+= len; break; //NetBIOS node type
andrewboyson 10:f0854784e960 148 case 47: len = *++p; p+= len; break; //NetBIOS scope
andrewboyson 10:f0854784e960 149 case 53: len = *++p; dhcpMessageType = *++p; break; //DHCP message type
andrewboyson 10:f0854784e960 150 case 51: DhcpLeaseTime = readOption32(&p); break; //Address lease time
andrewboyson 116:60521b29e4c9 151 case 54: DhcpServerIp = readIp(&p); break; //DHCP server
andrewboyson 10:f0854784e960 152 case 58: DhcpRenewalT1 = readOption32(&p); break; //T1
andrewboyson 10:f0854784e960 153 case 59: DhcpRenewalT2 = readOption32(&p); break; //T2
andrewboyson 10:f0854784e960 154 default:
andrewboyson 37:793b39683406 155 if (DhcpTrace) LogTimeF("Ignoring option %d\r\n", *p);
andrewboyson 10:f0854784e960 156 len = *++p;
andrewboyson 10:f0854784e960 157 p += len;
andrewboyson 10:f0854784e960 158 return;
andrewboyson 10:f0854784e960 159 }
andrewboyson 10:f0854784e960 160 p++;
andrewboyson 10:f0854784e960 161 }
andrewboyson 10:f0854784e960 162 }
andrewboyson 10:f0854784e960 163 static void writeIp(uint8_t code, uint32_t value, char** pp)
andrewboyson 10:f0854784e960 164 {
andrewboyson 10:f0854784e960 165 if (!value) return;
andrewboyson 10:f0854784e960 166
andrewboyson 10:f0854784e960 167 char* p = *pp;
andrewboyson 10:f0854784e960 168
andrewboyson 10:f0854784e960 169 *p++ = code;
andrewboyson 10:f0854784e960 170 *p++ = 4;
andrewboyson 10:f0854784e960 171 *p++ = (value & 0x000000FF) >> 0;
andrewboyson 10:f0854784e960 172 *p++ = (value & 0x0000FF00) >> 8;
andrewboyson 10:f0854784e960 173 *p++ = (value & 0x00FF0000) >> 16;
andrewboyson 10:f0854784e960 174 *p++ = (value & 0xFF000000) >> 24;
andrewboyson 10:f0854784e960 175
andrewboyson 10:f0854784e960 176 *pp += 6;
andrewboyson 10:f0854784e960 177 }
andrewboyson 10:f0854784e960 178 int sendRequest(void* pPacket, uint8_t code, uint32_t srvIp, uint32_t reqIp)
andrewboyson 10:f0854784e960 179 {
andrewboyson 10:f0854784e960 180
andrewboyson 10:f0854784e960 181 switch (code)
andrewboyson 10:f0854784e960 182 {
andrewboyson 10:f0854784e960 183 case DHCPDISCOVER:
andrewboyson 37:793b39683406 184 if (DhcpTrace) LogTimeF("DHCP -> discover");
andrewboyson 10:f0854784e960 185 break;
andrewboyson 10:f0854784e960 186 case DHCPREQUEST:
andrewboyson 37:793b39683406 187 if (DhcpTrace) LogTimeF("DHCP -> request");
andrewboyson 10:f0854784e960 188 break;
andrewboyson 10:f0854784e960 189 default:
andrewboyson 10:f0854784e960 190 LogTimeF("DHCP -> unknown message %d", code);
andrewboyson 10:f0854784e960 191 break;
andrewboyson 10:f0854784e960 192 }
andrewboyson 37:793b39683406 193 if (DhcpTrace)
andrewboyson 10:f0854784e960 194 {
andrewboyson 47:73af5c0b0dc2 195 Log(" server=" ); Ip4AddressLog(srvIp);
andrewboyson 47:73af5c0b0dc2 196 Log(" request="); Ip4AddressLog(reqIp);
andrewboyson 47:73af5c0b0dc2 197 Log(" local=" ); Ip4AddressLog(DhcpLocalIp);
andrewboyson 47:73af5c0b0dc2 198 Log("\r\n");
andrewboyson 10:f0854784e960 199 }
andrewboyson 10:f0854784e960 200
andrewboyson 10:f0854784e960 201 bool broadcast = DhcpLocalIp == 0;
andrewboyson 10:f0854784e960 202 uint16_t flags = 0;
andrewboyson 10:f0854784e960 203 if (broadcast) flags |= 0x0080; //0x8000 on the net == 0x0080 in little endian
andrewboyson 61:aad055f1b0d1 204 struct header* pHeader = (struct header*)pPacket;
andrewboyson 10:f0854784e960 205 pHeader->op = REQUEST;
andrewboyson 10:f0854784e960 206 pHeader->htype = ETHERNET;
andrewboyson 10:f0854784e960 207 pHeader->hlen = 6;
andrewboyson 10:f0854784e960 208 pHeader->hops = 0;
andrewboyson 10:f0854784e960 209 pHeader->xid = ID; //Randomly chosed transaction id used to associate messages to responses
andrewboyson 10:f0854784e960 210 pHeader->secs = 0; //Seconds since started to boot
andrewboyson 10:f0854784e960 211 pHeader->flags = flags; //Broadcast (1) Unicast (0)
andrewboyson 10:f0854784e960 212 pHeader->ciaddr = DhcpLocalIp; //'Client' address set by client or 0 if don't know address
andrewboyson 10:f0854784e960 213 pHeader->yiaddr = 0; //'Your' address returned by server
andrewboyson 10:f0854784e960 214 pHeader->siaddr = srvIp; //'Server' address to use if required
andrewboyson 10:f0854784e960 215 pHeader->giaddr = 0; //'Gateway' address
andrewboyson 13:9cd54f7db57a 216 memcpy(pHeader->chaddr, MacLocal, 6); //'Client hardware' address. 6 bytes for ethernet
andrewboyson 10:f0854784e960 217 memset(pHeader->legacy, 0, 192); //BootP legacy fill with zeros
andrewboyson 10:f0854784e960 218 pHeader->cookie = NetToHost32(COOKIE); //Magic cookie
andrewboyson 10:f0854784e960 219
andrewboyson 10:f0854784e960 220 char* pOptions = (char*)pPacket + HEADER_LENGTH;
andrewboyson 10:f0854784e960 221 char* p = pOptions;
andrewboyson 10:f0854784e960 222 *p++ = 53; //Message code
andrewboyson 10:f0854784e960 223 *p++ = 1;
andrewboyson 10:f0854784e960 224 *p++ = code;
andrewboyson 10:f0854784e960 225
andrewboyson 10:f0854784e960 226 writeIp(50, reqIp, &p); //Requested IP
andrewboyson 10:f0854784e960 227 writeIp(54, srvIp, &p); //Server ip
andrewboyson 10:f0854784e960 228
andrewboyson 10:f0854784e960 229 *p++ = 255; //End of options
andrewboyson 10:f0854784e960 230
andrewboyson 10:f0854784e960 231 return HEADER_LENGTH + p - pOptions;
andrewboyson 10:f0854784e960 232 }
andrewboyson 59:e0e556c8bd46 233 int DhcpHandleResponse(void (*traceback)(void), int sizeRx, void* pPacketRx, int* pSizeTx, void* pPacketTx)
andrewboyson 10:f0854784e960 234 {
andrewboyson 61:aad055f1b0d1 235 struct header* pHeaderRx = (struct header*)pPacketRx;
andrewboyson 10:f0854784e960 236
andrewboyson 59:e0e556c8bd46 237 uint8_t op = pHeaderRx->op;
andrewboyson 59:e0e556c8bd46 238 uint8_t htype = pHeaderRx->htype;
andrewboyson 59:e0e556c8bd46 239 uint8_t hlen = pHeaderRx->hlen;
andrewboyson 10:f0854784e960 240
andrewboyson 59:e0e556c8bd46 241 uint32_t xid = pHeaderRx->xid; //Randomly chosen transaction id used to associate messages to responses
andrewboyson 10:f0854784e960 242
andrewboyson 59:e0e556c8bd46 243 uint16_t secs = NetToHost16(pHeaderRx->secs);
andrewboyson 59:e0e556c8bd46 244 uint16_t flags = NetToHost16(pHeaderRx->flags);
andrewboyson 10:f0854784e960 245
andrewboyson 59:e0e556c8bd46 246 uint32_t yiaddr = pHeaderRx->yiaddr;
andrewboyson 59:e0e556c8bd46 247 uint32_t siaddr = pHeaderRx->siaddr;
andrewboyson 59:e0e556c8bd46 248 uint32_t cookie = NetToHost32(pHeaderRx->cookie);
andrewboyson 10:f0854784e960 249
andrewboyson 59:e0e556c8bd46 250 if (op != REPLY) return DO_NOTHING;
andrewboyson 59:e0e556c8bd46 251 if (htype != ETHERNET) return DO_NOTHING;
andrewboyson 59:e0e556c8bd46 252 if (hlen != 6) return DO_NOTHING;
andrewboyson 59:e0e556c8bd46 253 if (memcmp(pHeaderRx->chaddr, MacLocal, 6)) return DO_NOTHING;
andrewboyson 59:e0e556c8bd46 254 if (xid != ID) return DO_NOTHING;
andrewboyson 59:e0e556c8bd46 255 if (cookie != COOKIE) return DO_NOTHING;
andrewboyson 10:f0854784e960 256
andrewboyson 59:e0e556c8bd46 257 char* pOptions = (char*)pPacketRx + HEADER_LENGTH;
andrewboyson 59:e0e556c8bd46 258 readOptions(sizeRx - HEADER_LENGTH, pOptions);
andrewboyson 10:f0854784e960 259
andrewboyson 10:f0854784e960 260 switch (dhcpMessageType)
andrewboyson 10:f0854784e960 261 {
andrewboyson 10:f0854784e960 262 case DHCPOFFER:
andrewboyson 47:73af5c0b0dc2 263 if (DhcpTrace) { LogTime("DHCP <- offer ip "); Ip4AddressLog(yiaddr); Log("\r\n"); }
andrewboyson 59:e0e556c8bd46 264 *pSizeTx = sendRequest(pPacketTx, DHCPREQUEST, siaddr, yiaddr);
andrewboyson 10:f0854784e960 265 return BROADCAST;
andrewboyson 10:f0854784e960 266 case DHCPACK:
andrewboyson 47:73af5c0b0dc2 267 if (DhcpTrace) { LogTime("DHCP <- ack ip "); Ip4AddressLog(yiaddr); Log("\r\n"); }
andrewboyson 10:f0854784e960 268 DhcpLocalIp = yiaddr;
andrewboyson 119:8e1a7805b801 269 elapsedLifeMsTimer = MsTimerCount; //Start the life timer
andrewboyson 116:60521b29e4c9 270 delayMs = MIN_REPEAT_DELAY_TIME_MS; //Set the delay time back to minimum
andrewboyson 10:f0854784e960 271 break;
andrewboyson 10:f0854784e960 272 case DHCPNAK:
andrewboyson 47:73af5c0b0dc2 273 if (DhcpTrace) { LogTime("DHCP <- nack ip "); Ip4AddressLog(yiaddr); Log("\r\n"); }
andrewboyson 10:f0854784e960 274 break;
andrewboyson 10:f0854784e960 275 default:
andrewboyson 10:f0854784e960 276 LogTimeF("DHCP <- unknown message %d\r\n", dhcpMessageType);
andrewboyson 10:f0854784e960 277 break;
andrewboyson 10:f0854784e960 278 }
andrewboyson 10:f0854784e960 279 return DO_NOTHING;
andrewboyson 10:f0854784e960 280 }
andrewboyson 10:f0854784e960 281
andrewboyson 10:f0854784e960 282 int DhcpPollForRequestToSend(void* pPacket, int* pSize)
andrewboyson 116:60521b29e4c9 283 {
andrewboyson 119:8e1a7805b801 284 //Check if time to update
andrewboyson 119:8e1a7805b801 285 uint32_t elapsedTimeMs = MsTimerCount - elapsedLifeMsTimer;
andrewboyson 93:580fc113d9e9 286 uint32_t leaseTimeMs = DhcpLeaseTime * 1000;
andrewboyson 93:580fc113d9e9 287
andrewboyson 119:8e1a7805b801 288 if (DhcpLocalIp && elapsedTimeMs < (leaseTimeMs >> 1)) return DO_NOTHING; //Do nothing if have address and within T1
andrewboyson 10:f0854784e960 289
andrewboyson 119:8e1a7805b801 290 //Limit retries with a backoff delay
andrewboyson 119:8e1a7805b801 291 if (!MsTimerHasElapsed(repeatDelayMsTimer, delayMs)) return DO_NOTHING; //Don't retry within the delay time
andrewboyson 119:8e1a7805b801 292 delayMs <<= 1; //Backoff (double) the delay time after each attempt
andrewboyson 119:8e1a7805b801 293 if (delayMs > MAX_REPEAT_DELAY_TIME_MS) delayMs = MAX_REPEAT_DELAY_TIME_MS; //Don't go beyond a maximum
andrewboyson 119:8e1a7805b801 294 repeatDelayMsTimer = MsTimerCount; //Start the delay timer
andrewboyson 119:8e1a7805b801 295
andrewboyson 119:8e1a7805b801 296 //Send the renewal request
andrewboyson 10:f0854784e960 297 *pSize = 0;
andrewboyson 37:793b39683406 298 int dest = DO_NOTHING;
andrewboyson 93:580fc113d9e9 299 if (DhcpLocalIp && elapsedTimeMs < leaseTimeMs)
andrewboyson 10:f0854784e960 300 {
andrewboyson 116:60521b29e4c9 301 *pSize = sendRequest(pPacket, DHCPREQUEST, DhcpServerIp, DhcpLocalIp); //if within T2 then send request to the server - not broadcast
andrewboyson 37:793b39683406 302 dest = UNICAST_DHCP;
andrewboyson 10:f0854784e960 303 }
andrewboyson 10:f0854784e960 304 else
andrewboyson 10:f0854784e960 305 {
andrewboyson 37:793b39683406 306 if (DhcpTrace) LogTimeF("DHCP lease has expired\r\n");
andrewboyson 10:f0854784e960 307 DhcpLocalIp = 0;
andrewboyson 116:60521b29e4c9 308 DhcpServerIp = 0;
andrewboyson 10:f0854784e960 309 *pSize = sendRequest(pPacket, DHCPDISCOVER, 0, 0); //If outside T2 then start from scratch to do a full DHCP
andrewboyson 37:793b39683406 310 dest = BROADCAST;
andrewboyson 10:f0854784e960 311 }
andrewboyson 37:793b39683406 312 return ActionMakeFromDestAndTrace(dest, DhcpTrace);
andrewboyson 10:f0854784e960 313 }