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udp/dns/dnsquery.c@61:aad055f1b0d1, 2018-01-11 (annotated)

Committer:
andrewboyson
Date:
Thu Jan 11 17:38:21 2018 +0000
Revision:
61:aad055f1b0d1
Parent:
udp/dns/dnsquery.cpp@59:e0e556c8bd46
Child:
65:37acccf2752f
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 #include <stdbool.h>
andrewboyson 61:aad055f1b0d1 3
andrewboyson 13:9cd54f7db57a 4 #include "log.h"
andrewboyson 43:bc028d5a6424 5 #include "clock.h"
andrewboyson 13:9cd54f7db57a 6 #include "net.h"
andrewboyson 37:793b39683406 7 #include "action.h"
andrewboyson 49:1a6336f2b3f9 8 #include "ip4addr.h"
andrewboyson 49:1a6336f2b3f9 9 #include "ip6addr.h"
andrewboyson 13:9cd54f7db57a 10 #include "dhcp.h"
andrewboyson 13:9cd54f7db57a 11 #include "dns.h"
andrewboyson 13:9cd54f7db57a 12 #include "udp.h"
andrewboyson 13:9cd54f7db57a 13 #include "slaac.h"
andrewboyson 13:9cd54f7db57a 14 #include "dnshdr.h"
andrewboyson 13:9cd54f7db57a 15 #include "dnsname.h"
andrewboyson 13:9cd54f7db57a 16
andrewboyson 37:793b39683406 17 bool DnsQueryTrace = false;
andrewboyson 13:9cd54f7db57a 18
andrewboyson 13:9cd54f7db57a 19 #define TIME_OUT_SENT 3
andrewboyson 13:9cd54f7db57a 20
andrewboyson 13:9cd54f7db57a 21 #define MDNS_UNICAST false
andrewboyson 13:9cd54f7db57a 22
andrewboyson 35:93c39d260a83 23 char DnsQueryName[DNS_MAX_LABEL_LENGTH+1];
andrewboyson 13:9cd54f7db57a 24 uint32_t DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 25 char DnsQueryIp6[16];
andrewboyson 13:9cd54f7db57a 26
andrewboyson 30:e34173b7585c 27 char DnsQueryRecordType = DNS_RECORD_NONE;
andrewboyson 30:e34173b7585c 28 int DnsQueryProtocol = DNS_PROTOCOL_NONE;
andrewboyson 30:e34173b7585c 29 bool DnsQueryIsBusy = false;
andrewboyson 13:9cd54f7db57a 30
andrewboyson 13:9cd54f7db57a 31 static uint32_t started = 0;
andrewboyson 13:9cd54f7db57a 32 static uint32_t elapsed = 0;
andrewboyson 13:9cd54f7db57a 33 static void reap()
andrewboyson 13:9cd54f7db57a 34 {
andrewboyson 13:9cd54f7db57a 35 if (!DnsQueryIsBusy) return;
andrewboyson 13:9cd54f7db57a 36
andrewboyson 13:9cd54f7db57a 37 if (elapsed - started >= TIME_OUT_SENT)
andrewboyson 13:9cd54f7db57a 38 {
andrewboyson 13:9cd54f7db57a 39 LogTimeF("DNS reaped ongoing request for ");
andrewboyson 13:9cd54f7db57a 40 if (DnsQueryName[0]) LogF("name %s", DnsQueryName);
andrewboyson 13:9cd54f7db57a 41 if (DnsQueryIp4)
andrewboyson 13:9cd54f7db57a 42 {
andrewboyson 47:73af5c0b0dc2 43 Log("ip4 "); Ip4AddressLog(DnsQueryIp4);
andrewboyson 13:9cd54f7db57a 44 }
andrewboyson 13:9cd54f7db57a 45 if (DnsQueryIp6[0])
andrewboyson 13:9cd54f7db57a 46 {
andrewboyson 47:73af5c0b0dc2 47 Log("ip6 "); Ip6AddressLog(DnsQueryIp6);
andrewboyson 13:9cd54f7db57a 48 }
andrewboyson 13:9cd54f7db57a 49 LogF("\r\n");
andrewboyson 13:9cd54f7db57a 50
andrewboyson 13:9cd54f7db57a 51 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 52 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 53 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 54 DnsQueryIsBusy = false;
andrewboyson 13:9cd54f7db57a 55 started = 0;
andrewboyson 13:9cd54f7db57a 56 DnsQueryProtocol = DNS_PROTOCOL_NONE;
andrewboyson 30:e34173b7585c 57 DnsQueryRecordType = DNS_RECORD_NONE;
andrewboyson 13:9cd54f7db57a 58 }
andrewboyson 13:9cd54f7db57a 59 }
andrewboyson 43:bc028d5a6424 60 void DnsQueryMain()
andrewboyson 13:9cd54f7db57a 61 {
andrewboyson 43:bc028d5a6424 62 if (ClockTicked)
andrewboyson 43:bc028d5a6424 63 {
andrewboyson 43:bc028d5a6424 64 elapsed++;
andrewboyson 43:bc028d5a6424 65 reap();
andrewboyson 43:bc028d5a6424 66 }
andrewboyson 13:9cd54f7db57a 67 }
andrewboyson 13:9cd54f7db57a 68 void DnsQueryIp4FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 69 {
andrewboyson 32:679654f2d023 70 DnsMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 71 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 72 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 73 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 74 started = elapsed;
andrewboyson 13:9cd54f7db57a 75 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 76 DnsQueryRecordType = DNS_RECORD_A;
andrewboyson 13:9cd54f7db57a 77 }
andrewboyson 13:9cd54f7db57a 78 void DnsQueryIp6FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 79 {
andrewboyson 32:679654f2d023 80 DnsMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 81 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 82 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 83 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 84 started = elapsed;
andrewboyson 13:9cd54f7db57a 85 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 86 DnsQueryRecordType = DNS_RECORD_AAAA;
andrewboyson 13:9cd54f7db57a 87 }
andrewboyson 13:9cd54f7db57a 88 void DnsQueryNameFromIp4(uint32_t ip, int protocol)
andrewboyson 13:9cd54f7db57a 89 {
andrewboyson 13:9cd54f7db57a 90 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 91 DnsQueryIp4 = ip;
andrewboyson 13:9cd54f7db57a 92 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 93 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 94 started = elapsed;
andrewboyson 13:9cd54f7db57a 95 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 96 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 13:9cd54f7db57a 97 }
andrewboyson 13:9cd54f7db57a 98 void DnsQueryNameFromIp6(char* ip, int protocol)
andrewboyson 13:9cd54f7db57a 99 {
andrewboyson 13:9cd54f7db57a 100 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 101 DnsQueryIp4 = 0;
andrewboyson 49:1a6336f2b3f9 102 Ip6AddressCopy(DnsQueryIp6, ip);
andrewboyson 13:9cd54f7db57a 103 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 104 started = elapsed;
andrewboyson 13:9cd54f7db57a 105 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 106 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 30:e34173b7585c 107 }
andrewboyson 30:e34173b7585c 108 static void logQuery()
andrewboyson 30:e34173b7585c 109 {
andrewboyson 43:bc028d5a6424 110 if (NetTraceNewLine) Log("\r\n");
andrewboyson 47:73af5c0b0dc2 111 LogTimeF("DnsQuery sent ");
andrewboyson 47:73af5c0b0dc2 112 DnsProtocolLog(DnsQueryProtocol);
andrewboyson 47:73af5c0b0dc2 113 Log(" request for ");
andrewboyson 47:73af5c0b0dc2 114 DnsRecordTypeLog(DnsQueryRecordType);
andrewboyson 47:73af5c0b0dc2 115 Log(" ");
andrewboyson 30:e34173b7585c 116 if (DnsQueryIp4) //Reverse
andrewboyson 30:e34173b7585c 117 {
andrewboyson 47:73af5c0b0dc2 118 Ip4AddressLog(DnsQueryIp4);
andrewboyson 30:e34173b7585c 119 }
andrewboyson 30:e34173b7585c 120 else if (DnsQueryIp6[0])
andrewboyson 30:e34173b7585c 121 {
andrewboyson 47:73af5c0b0dc2 122 Ip6AddressLog(DnsQueryIp6);
andrewboyson 30:e34173b7585c 123 }
andrewboyson 30:e34173b7585c 124 else //Forward
andrewboyson 30:e34173b7585c 125 {
andrewboyson 47:73af5c0b0dc2 126 Log(DnsQueryName);
andrewboyson 30:e34173b7585c 127 }
andrewboyson 47:73af5c0b0dc2 128 Log("\r\n");
andrewboyson 13:9cd54f7db57a 129 }
andrewboyson 59:e0e556c8bd46 130 int DnsQueryPoll(void* pPacket, int* pSize)
andrewboyson 13:9cd54f7db57a 131 {
andrewboyson 59:e0e556c8bd46 132 DnsHdrSetup(pPacket, *pSize);
andrewboyson 59:e0e556c8bd46 133
andrewboyson 13:9cd54f7db57a 134 if (!DnsQueryIsBusy) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 135 if (DnsQueryProtocol == DNS_PROTOCOL_UDNS && DhcpLocalIp == 0) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 136
andrewboyson 57:e0fb648acf48 137 NetTraceHostCheckIp6(DnsQueryIp6);
andrewboyson 57:e0fb648acf48 138
andrewboyson 57:e0fb648acf48 139 if (DnsQueryTrace || NetTraceHostGetMatched()) logQuery();
andrewboyson 30:e34173b7585c 140
andrewboyson 13:9cd54f7db57a 141 static uint16_t id = 0;
andrewboyson 13:9cd54f7db57a 142 DnsHdrId = ++id;
andrewboyson 13:9cd54f7db57a 143 DnsHdrIsReply = false;
andrewboyson 13:9cd54f7db57a 144 DnsHdrIsRecursiveQuery = false;
andrewboyson 13:9cd54f7db57a 145
andrewboyson 13:9cd54f7db57a 146 DnsHdrQdcount = 1;
andrewboyson 13:9cd54f7db57a 147 DnsHdrAncount = 0;
andrewboyson 13:9cd54f7db57a 148 DnsHdrNscount = 0;
andrewboyson 13:9cd54f7db57a 149 DnsHdrArcount = 0;
andrewboyson 13:9cd54f7db57a 150
andrewboyson 13:9cd54f7db57a 151 DnsHdrWrite();
andrewboyson 13:9cd54f7db57a 152 char* p = DnsHdrData;
andrewboyson 13:9cd54f7db57a 153
andrewboyson 30:e34173b7585c 154 if (DnsQueryIp4 ) DnsNameEncodeIp4(DnsQueryIp4, &p);
andrewboyson 30:e34173b7585c 155 else if (DnsQueryIp6[0]) DnsNameEncodeIp6(DnsQueryIp6, &p);
andrewboyson 37:793b39683406 156 else DnsNameEncodePtr(DnsQueryName, &p);
andrewboyson 30:e34173b7585c 157
andrewboyson 30:e34173b7585c 158 *p++ = 0;
andrewboyson 30:e34173b7585c 159 *p++ = DnsQueryRecordType;
andrewboyson 13:9cd54f7db57a 160 *p++ = DnsQueryProtocol == DNS_PROTOCOL_MDNS && MDNS_UNICAST ? 0x80 : 0; //Set the 15th bit (UNICAST_RESPONSE) to 1 if MDNS
andrewboyson 13:9cd54f7db57a 161 *p++ = 1; //QCLASS_IN = 1 - internet
andrewboyson 13:9cd54f7db57a 162
andrewboyson 13:9cd54f7db57a 163 *pSize = p - DnsHdrPacket;
andrewboyson 13:9cd54f7db57a 164
andrewboyson 13:9cd54f7db57a 165 DnsQueryIsBusy = false;
andrewboyson 38:cc8945857a0d 166
andrewboyson 57:e0fb648acf48 167 if (DnsQueryTrace || NetTraceHostGetMatched()) DnsHdrLog(DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 168
andrewboyson 37:793b39683406 169 int dest = DO_NOTHING;
andrewboyson 37:793b39683406 170
andrewboyson 13:9cd54f7db57a 171 switch (DnsQueryProtocol)
andrewboyson 13:9cd54f7db57a 172 {
andrewboyson 37:793b39683406 173 case DNS_PROTOCOL_UDNS: dest = UNICAST_DNS; break; //IPv6 ==> NdpDnsServer; IPv4 ==> DhcpDnsServer
andrewboyson 37:793b39683406 174 case DNS_PROTOCOL_MDNS: dest = MULTICAST_MDNS; break;
andrewboyson 37:793b39683406 175 case DNS_PROTOCOL_LLMNR: dest = MULTICAST_LLMNR; break;
andrewboyson 13:9cd54f7db57a 176 default:
andrewboyson 13:9cd54f7db57a 177 LogTimeF("DNS unknown query protocol %d\r\n", DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 178 return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 179 }
andrewboyson 37:793b39683406 180
andrewboyson 57:e0fb648acf48 181 return ActionMakeFromDestAndTrace(dest, DnsQueryTrace || NetTraceHostGetMatched());
andrewboyson 13:9cd54f7db57a 182 }