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

Committer:
andrewboyson
Date:
Mon Mar 11 16:42:45 2019 +0000
Revision:
128:79052cb4a41c
Parent:
93:580fc113d9e9
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
andrewboyson 13:9cd54f7db57a 4 #include "log.h"
andrewboyson 93:580fc113d9e9 5 #include "mstimer.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 128:79052cb4a41c 16 #include "dnslabel.h"
andrewboyson 13:9cd54f7db57a 17
andrewboyson 37:793b39683406 18 bool DnsQueryTrace = false;
andrewboyson 13:9cd54f7db57a 19
andrewboyson 93:580fc113d9e9 20 #define TIME_OUT_SENT_MS 3000
andrewboyson 13:9cd54f7db57a 21
andrewboyson 13:9cd54f7db57a 22 #define MDNS_UNICAST false
andrewboyson 13:9cd54f7db57a 23
andrewboyson 35:93c39d260a83 24 char DnsQueryName[DNS_MAX_LABEL_LENGTH+1];
andrewboyson 13:9cd54f7db57a 25 uint32_t DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 26 char DnsQueryIp6[16];
andrewboyson 13:9cd54f7db57a 27
andrewboyson 30:e34173b7585c 28 char DnsQueryRecordType = DNS_RECORD_NONE;
andrewboyson 30:e34173b7585c 29 int DnsQueryProtocol = DNS_PROTOCOL_NONE;
andrewboyson 30:e34173b7585c 30 bool DnsQueryIsBusy = false;
andrewboyson 13:9cd54f7db57a 31
andrewboyson 93:580fc113d9e9 32 static uint32_t startedMs = 0;
andrewboyson 13:9cd54f7db57a 33 static void reap()
andrewboyson 13:9cd54f7db57a 34 {
andrewboyson 13:9cd54f7db57a 35 if (!DnsQueryIsBusy) return;
andrewboyson 13:9cd54f7db57a 36
andrewboyson 93:580fc113d9e9 37 if (MsTimerHasElapsed(startedMs, TIME_OUT_SENT_MS))
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 93:580fc113d9e9 55 startedMs = MsTimerCount;
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 93:580fc113d9e9 62 reap();
andrewboyson 13:9cd54f7db57a 63 }
andrewboyson 13:9cd54f7db57a 64 void DnsQueryIp4FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 65 {
andrewboyson 128:79052cb4a41c 66 DnsLabelMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 67 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 68 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 69 DnsQueryIsBusy = true;
andrewboyson 93:580fc113d9e9 70 startedMs = MsTimerCount;
andrewboyson 13:9cd54f7db57a 71 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 72 DnsQueryRecordType = DNS_RECORD_A;
andrewboyson 13:9cd54f7db57a 73 }
andrewboyson 13:9cd54f7db57a 74 void DnsQueryIp6FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 75 {
andrewboyson 128:79052cb4a41c 76 DnsLabelMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 77 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 78 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 79 DnsQueryIsBusy = true;
andrewboyson 93:580fc113d9e9 80 startedMs = MsTimerCount;
andrewboyson 13:9cd54f7db57a 81 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 82 DnsQueryRecordType = DNS_RECORD_AAAA;
andrewboyson 13:9cd54f7db57a 83 }
andrewboyson 13:9cd54f7db57a 84 void DnsQueryNameFromIp4(uint32_t ip, int protocol)
andrewboyson 13:9cd54f7db57a 85 {
andrewboyson 13:9cd54f7db57a 86 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 87 DnsQueryIp4 = ip;
andrewboyson 13:9cd54f7db57a 88 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 89 DnsQueryIsBusy = true;
andrewboyson 93:580fc113d9e9 90 startedMs = MsTimerCount;
andrewboyson 13:9cd54f7db57a 91 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 92 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 13:9cd54f7db57a 93 }
andrewboyson 13:9cd54f7db57a 94 void DnsQueryNameFromIp6(char* ip, int protocol)
andrewboyson 13:9cd54f7db57a 95 {
andrewboyson 13:9cd54f7db57a 96 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 97 DnsQueryIp4 = 0;
andrewboyson 49:1a6336f2b3f9 98 Ip6AddressCopy(DnsQueryIp6, ip);
andrewboyson 13:9cd54f7db57a 99 DnsQueryIsBusy = true;
andrewboyson 93:580fc113d9e9 100 startedMs = MsTimerCount;
andrewboyson 13:9cd54f7db57a 101 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 102 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 30:e34173b7585c 103 }
andrewboyson 30:e34173b7585c 104 static void logQuery()
andrewboyson 30:e34173b7585c 105 {
andrewboyson 43:bc028d5a6424 106 if (NetTraceNewLine) Log("\r\n");
andrewboyson 47:73af5c0b0dc2 107 LogTimeF("DnsQuery sent ");
andrewboyson 47:73af5c0b0dc2 108 DnsProtocolLog(DnsQueryProtocol);
andrewboyson 47:73af5c0b0dc2 109 Log(" request for ");
andrewboyson 47:73af5c0b0dc2 110 DnsRecordTypeLog(DnsQueryRecordType);
andrewboyson 47:73af5c0b0dc2 111 Log(" ");
andrewboyson 30:e34173b7585c 112 if (DnsQueryIp4) //Reverse
andrewboyson 30:e34173b7585c 113 {
andrewboyson 47:73af5c0b0dc2 114 Ip4AddressLog(DnsQueryIp4);
andrewboyson 30:e34173b7585c 115 }
andrewboyson 30:e34173b7585c 116 else if (DnsQueryIp6[0])
andrewboyson 30:e34173b7585c 117 {
andrewboyson 47:73af5c0b0dc2 118 Ip6AddressLog(DnsQueryIp6);
andrewboyson 30:e34173b7585c 119 }
andrewboyson 30:e34173b7585c 120 else //Forward
andrewboyson 30:e34173b7585c 121 {
andrewboyson 47:73af5c0b0dc2 122 Log(DnsQueryName);
andrewboyson 30:e34173b7585c 123 }
andrewboyson 47:73af5c0b0dc2 124 Log("\r\n");
andrewboyson 13:9cd54f7db57a 125 }
andrewboyson 59:e0e556c8bd46 126 int DnsQueryPoll(void* pPacket, int* pSize)
andrewboyson 13:9cd54f7db57a 127 {
andrewboyson 59:e0e556c8bd46 128 DnsHdrSetup(pPacket, *pSize);
andrewboyson 59:e0e556c8bd46 129
andrewboyson 13:9cd54f7db57a 130 if (!DnsQueryIsBusy) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 131 if (DnsQueryProtocol == DNS_PROTOCOL_UDNS && DhcpLocalIp == 0) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 132
andrewboyson 57:e0fb648acf48 133 NetTraceHostCheckIp6(DnsQueryIp6);
andrewboyson 57:e0fb648acf48 134
andrewboyson 57:e0fb648acf48 135 if (DnsQueryTrace || NetTraceHostGetMatched()) logQuery();
andrewboyson 30:e34173b7585c 136
andrewboyson 13:9cd54f7db57a 137 static uint16_t id = 0;
andrewboyson 13:9cd54f7db57a 138 DnsHdrId = ++id;
andrewboyson 13:9cd54f7db57a 139 DnsHdrIsReply = false;
andrewboyson 13:9cd54f7db57a 140 DnsHdrIsRecursiveQuery = false;
andrewboyson 13:9cd54f7db57a 141
andrewboyson 13:9cd54f7db57a 142 DnsHdrQdcount = 1;
andrewboyson 13:9cd54f7db57a 143 DnsHdrAncount = 0;
andrewboyson 13:9cd54f7db57a 144 DnsHdrNscount = 0;
andrewboyson 13:9cd54f7db57a 145 DnsHdrArcount = 0;
andrewboyson 13:9cd54f7db57a 146
andrewboyson 13:9cd54f7db57a 147 DnsHdrWrite();
andrewboyson 13:9cd54f7db57a 148 char* p = DnsHdrData;
andrewboyson 13:9cd54f7db57a 149
andrewboyson 30:e34173b7585c 150 if (DnsQueryIp4 ) DnsNameEncodeIp4(DnsQueryIp4, &p);
andrewboyson 30:e34173b7585c 151 else if (DnsQueryIp6[0]) DnsNameEncodeIp6(DnsQueryIp6, &p);
andrewboyson 37:793b39683406 152 else DnsNameEncodePtr(DnsQueryName, &p);
andrewboyson 30:e34173b7585c 153
andrewboyson 30:e34173b7585c 154 *p++ = 0;
andrewboyson 30:e34173b7585c 155 *p++ = DnsQueryRecordType;
andrewboyson 13:9cd54f7db57a 156 *p++ = DnsQueryProtocol == DNS_PROTOCOL_MDNS && MDNS_UNICAST ? 0x80 : 0; //Set the 15th bit (UNICAST_RESPONSE) to 1 if MDNS
andrewboyson 13:9cd54f7db57a 157 *p++ = 1; //QCLASS_IN = 1 - internet
andrewboyson 13:9cd54f7db57a 158
andrewboyson 13:9cd54f7db57a 159 *pSize = p - DnsHdrPacket;
andrewboyson 13:9cd54f7db57a 160
andrewboyson 13:9cd54f7db57a 161 DnsQueryIsBusy = false;
andrewboyson 38:cc8945857a0d 162
andrewboyson 57:e0fb648acf48 163 if (DnsQueryTrace || NetTraceHostGetMatched()) DnsHdrLog(DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 164
andrewboyson 37:793b39683406 165 int dest = DO_NOTHING;
andrewboyson 37:793b39683406 166
andrewboyson 13:9cd54f7db57a 167 switch (DnsQueryProtocol)
andrewboyson 13:9cd54f7db57a 168 {
andrewboyson 37:793b39683406 169 case DNS_PROTOCOL_UDNS: dest = UNICAST_DNS; break; //IPv6 ==> NdpDnsServer; IPv4 ==> DhcpDnsServer
andrewboyson 37:793b39683406 170 case DNS_PROTOCOL_MDNS: dest = MULTICAST_MDNS; break;
andrewboyson 37:793b39683406 171 case DNS_PROTOCOL_LLMNR: dest = MULTICAST_LLMNR; break;
andrewboyson 13:9cd54f7db57a 172 default:
andrewboyson 13:9cd54f7db57a 173 LogTimeF("DNS unknown query protocol %d\r\n", DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 174 return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 175 }
andrewboyson 37:793b39683406 176
andrewboyson 57:e0fb648acf48 177 return ActionMakeFromDestAndTrace(dest, DnsQueryTrace || NetTraceHostGetMatched());
andrewboyson 13:9cd54f7db57a 178 }