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.cpp@38:cc8945857a0d, 2017-10-04 (annotated)

Committer:
andrewboyson
Date:
Wed Oct 04 11:22:33 2017 +0000
Revision:
38:cc8945857a0d
Parent:
37:793b39683406
Child:
43:bc028d5a6424
Added header log to DnsQuery

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 13:9cd54f7db57a 1 #include "mbed.h"
andrewboyson 13:9cd54f7db57a 2 #include "log.h"
andrewboyson 13:9cd54f7db57a 3 #include "net.h"
andrewboyson 37:793b39683406 4 #include "action.h"
andrewboyson 14:e75a59c1123d 5 #include "ip4.h"
andrewboyson 14:e75a59c1123d 6 #include "ip6.h"
andrewboyson 13:9cd54f7db57a 7 #include "dhcp.h"
andrewboyson 13:9cd54f7db57a 8 #include "dns.h"
andrewboyson 13:9cd54f7db57a 9 #include "udp.h"
andrewboyson 13:9cd54f7db57a 10 #include "slaac.h"
andrewboyson 13:9cd54f7db57a 11 #include "dnshdr.h"
andrewboyson 13:9cd54f7db57a 12 #include "dnsname.h"
andrewboyson 13:9cd54f7db57a 13
andrewboyson 37:793b39683406 14 bool DnsQueryTrace = false;
andrewboyson 13:9cd54f7db57a 15
andrewboyson 13:9cd54f7db57a 16 #define TIME_OUT_SENT 3
andrewboyson 13:9cd54f7db57a 17
andrewboyson 13:9cd54f7db57a 18 #define MDNS_UNICAST false
andrewboyson 13:9cd54f7db57a 19
andrewboyson 35:93c39d260a83 20 char DnsQueryName[DNS_MAX_LABEL_LENGTH+1];
andrewboyson 13:9cd54f7db57a 21 uint32_t DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 22 char DnsQueryIp6[16];
andrewboyson 13:9cd54f7db57a 23
andrewboyson 30:e34173b7585c 24 char DnsQueryRecordType = DNS_RECORD_NONE;
andrewboyson 30:e34173b7585c 25 int DnsQueryProtocol = DNS_PROTOCOL_NONE;
andrewboyson 30:e34173b7585c 26 bool DnsQueryIsBusy = false;
andrewboyson 13:9cd54f7db57a 27
andrewboyson 13:9cd54f7db57a 28 static uint32_t started = 0;
andrewboyson 13:9cd54f7db57a 29 static uint32_t elapsed = 0;
andrewboyson 13:9cd54f7db57a 30 static void reap()
andrewboyson 13:9cd54f7db57a 31 {
andrewboyson 13:9cd54f7db57a 32 if (!DnsQueryIsBusy) return;
andrewboyson 13:9cd54f7db57a 33
andrewboyson 13:9cd54f7db57a 34 if (elapsed - started >= TIME_OUT_SENT)
andrewboyson 13:9cd54f7db57a 35 {
andrewboyson 13:9cd54f7db57a 36 char text[100];
andrewboyson 13:9cd54f7db57a 37 LogTimeF("DNS reaped ongoing request for ");
andrewboyson 13:9cd54f7db57a 38 if (DnsQueryName[0]) LogF("name %s", DnsQueryName);
andrewboyson 13:9cd54f7db57a 39 if (DnsQueryIp4)
andrewboyson 13:9cd54f7db57a 40 {
andrewboyson 14:e75a59c1123d 41 Ip4AddressToString(DnsQueryIp4, sizeof(text), text);
andrewboyson 13:9cd54f7db57a 42 LogF("ip4 %s", text);
andrewboyson 13:9cd54f7db57a 43 }
andrewboyson 13:9cd54f7db57a 44 if (DnsQueryIp6[0])
andrewboyson 13:9cd54f7db57a 45 {
andrewboyson 14:e75a59c1123d 46 Ip6AddressToString(DnsQueryIp6, sizeof(text), text);
andrewboyson 13:9cd54f7db57a 47 LogF("ip6 %s", text);
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 13:9cd54f7db57a 60 void DnsQueryTick()
andrewboyson 13:9cd54f7db57a 61 {
andrewboyson 13:9cd54f7db57a 62 elapsed++;
andrewboyson 13:9cd54f7db57a 63 reap();
andrewboyson 13:9cd54f7db57a 64 }
andrewboyson 13:9cd54f7db57a 65 void DnsQueryIp4FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 66 {
andrewboyson 32:679654f2d023 67 DnsMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 68 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 69 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 70 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 71 started = elapsed;
andrewboyson 13:9cd54f7db57a 72 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 73 DnsQueryRecordType = DNS_RECORD_A;
andrewboyson 13:9cd54f7db57a 74 }
andrewboyson 13:9cd54f7db57a 75 void DnsQueryIp6FromName(char * name, int protocol)
andrewboyson 13:9cd54f7db57a 76 {
andrewboyson 32:679654f2d023 77 DnsMakeFullNameFromName(protocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 13:9cd54f7db57a 78 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 79 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 80 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 81 started = elapsed;
andrewboyson 13:9cd54f7db57a 82 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 83 DnsQueryRecordType = DNS_RECORD_AAAA;
andrewboyson 13:9cd54f7db57a 84 }
andrewboyson 13:9cd54f7db57a 85 void DnsQueryNameFromIp4(uint32_t ip, int protocol)
andrewboyson 13:9cd54f7db57a 86 {
andrewboyson 13:9cd54f7db57a 87 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 88 DnsQueryIp4 = ip;
andrewboyson 13:9cd54f7db57a 89 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 90 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 91 started = elapsed;
andrewboyson 13:9cd54f7db57a 92 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 93 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 13:9cd54f7db57a 94 }
andrewboyson 13:9cd54f7db57a 95 void DnsQueryNameFromIp6(char* ip, int protocol)
andrewboyson 13:9cd54f7db57a 96 {
andrewboyson 13:9cd54f7db57a 97 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 98 DnsQueryIp4 = 0;
andrewboyson 36:900e24b27bfb 99 Ip6Copy(DnsQueryIp6, ip);
andrewboyson 13:9cd54f7db57a 100 DnsQueryIsBusy = true;
andrewboyson 13:9cd54f7db57a 101 started = elapsed;
andrewboyson 13:9cd54f7db57a 102 DnsQueryProtocol = protocol;
andrewboyson 30:e34173b7585c 103 DnsQueryRecordType = DNS_RECORD_PTR;
andrewboyson 30:e34173b7585c 104 }
andrewboyson 30:e34173b7585c 105 static void logQuery()
andrewboyson 30:e34173b7585c 106 {
andrewboyson 30:e34173b7585c 107 char text[60];
andrewboyson 30:e34173b7585c 108 DnsProtocolToString(DnsQueryProtocol, sizeof(text), text);
andrewboyson 32:679654f2d023 109 LogTimeF("DnsQuery sent %s request for ", text);
andrewboyson 30:e34173b7585c 110 DnsRecordTypeToString(DnsQueryRecordType, sizeof(text), text);
andrewboyson 30:e34173b7585c 111 LogF("%s ", text);
andrewboyson 30:e34173b7585c 112 if (DnsQueryIp4) //Reverse
andrewboyson 30:e34173b7585c 113 {
andrewboyson 30:e34173b7585c 114 Ip4AddressToString(DnsQueryIp4, sizeof(text), text);
andrewboyson 30:e34173b7585c 115 LogF("%s\r\n", text);
andrewboyson 30:e34173b7585c 116 }
andrewboyson 30:e34173b7585c 117 else if (DnsQueryIp6[0])
andrewboyson 30:e34173b7585c 118 {
andrewboyson 30:e34173b7585c 119 Ip6AddressToString(DnsQueryIp6, sizeof(text), text);
andrewboyson 30:e34173b7585c 120 LogF("%s\r\n", text);
andrewboyson 30:e34173b7585c 121 }
andrewboyson 30:e34173b7585c 122 else //Forward
andrewboyson 30:e34173b7585c 123 {
andrewboyson 30:e34173b7585c 124 LogF("%s\r\n", DnsQueryName);
andrewboyson 30:e34173b7585c 125 }
andrewboyson 13:9cd54f7db57a 126 }
andrewboyson 13:9cd54f7db57a 127 int DnsQueryPoll(int* pSize)
andrewboyson 13:9cd54f7db57a 128 {
andrewboyson 13:9cd54f7db57a 129 if (!DnsQueryIsBusy) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 130 if (DnsQueryProtocol == DNS_PROTOCOL_UDNS && DhcpLocalIp == 0) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 131
andrewboyson 37:793b39683406 132 if (DnsQueryTrace) logQuery();
andrewboyson 30:e34173b7585c 133
andrewboyson 13:9cd54f7db57a 134 static uint16_t id = 0;
andrewboyson 13:9cd54f7db57a 135 DnsHdrId = ++id;
andrewboyson 13:9cd54f7db57a 136 DnsHdrIsReply = false;
andrewboyson 13:9cd54f7db57a 137 DnsHdrIsRecursiveQuery = false;
andrewboyson 13:9cd54f7db57a 138
andrewboyson 13:9cd54f7db57a 139 DnsHdrQdcount = 1;
andrewboyson 13:9cd54f7db57a 140 DnsHdrAncount = 0;
andrewboyson 13:9cd54f7db57a 141 DnsHdrNscount = 0;
andrewboyson 13:9cd54f7db57a 142 DnsHdrArcount = 0;
andrewboyson 13:9cd54f7db57a 143
andrewboyson 13:9cd54f7db57a 144 DnsHdrWrite();
andrewboyson 13:9cd54f7db57a 145 char* p = DnsHdrData;
andrewboyson 13:9cd54f7db57a 146
andrewboyson 30:e34173b7585c 147 if (DnsQueryIp4 ) DnsNameEncodeIp4(DnsQueryIp4, &p);
andrewboyson 30:e34173b7585c 148 else if (DnsQueryIp6[0]) DnsNameEncodeIp6(DnsQueryIp6, &p);
andrewboyson 37:793b39683406 149 else DnsNameEncodePtr(DnsQueryName, &p);
andrewboyson 30:e34173b7585c 150
andrewboyson 30:e34173b7585c 151 *p++ = 0;
andrewboyson 30:e34173b7585c 152 *p++ = DnsQueryRecordType;
andrewboyson 13:9cd54f7db57a 153 *p++ = DnsQueryProtocol == DNS_PROTOCOL_MDNS && MDNS_UNICAST ? 0x80 : 0; //Set the 15th bit (UNICAST_RESPONSE) to 1 if MDNS
andrewboyson 13:9cd54f7db57a 154 *p++ = 1; //QCLASS_IN = 1 - internet
andrewboyson 13:9cd54f7db57a 155
andrewboyson 13:9cd54f7db57a 156 *pSize = p - DnsHdrPacket;
andrewboyson 13:9cd54f7db57a 157
andrewboyson 13:9cd54f7db57a 158 DnsQueryIsBusy = false;
andrewboyson 38:cc8945857a0d 159
andrewboyson 38:cc8945857a0d 160 if (DnsQueryTrace) DnsHdrLog(DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 161
andrewboyson 37:793b39683406 162 int dest = DO_NOTHING;
andrewboyson 37:793b39683406 163
andrewboyson 13:9cd54f7db57a 164 switch (DnsQueryProtocol)
andrewboyson 13:9cd54f7db57a 165 {
andrewboyson 37:793b39683406 166 case DNS_PROTOCOL_UDNS: dest = UNICAST_DNS; break; //IPv6 ==> NdpDnsServer; IPv4 ==> DhcpDnsServer
andrewboyson 37:793b39683406 167 case DNS_PROTOCOL_MDNS: dest = MULTICAST_MDNS; break;
andrewboyson 37:793b39683406 168 case DNS_PROTOCOL_LLMNR: dest = MULTICAST_LLMNR; break;
andrewboyson 13:9cd54f7db57a 169 default:
andrewboyson 13:9cd54f7db57a 170 LogTimeF("DNS unknown query protocol %d\r\n", DnsQueryProtocol);
andrewboyson 13:9cd54f7db57a 171 return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 172 }
andrewboyson 37:793b39683406 173
andrewboyson 37:793b39683406 174 return ActionMakeFromDestAndTrace(dest, DnsQueryTrace);
andrewboyson 13:9cd54f7db57a 175 }