Sergey Pastor / 1

Webserver+3d print

Dependents:   Nucleo

cyclone_tcp/netbios/nbns_responder.c@0:8918a71cdbe9, 2017-02-04 (annotated)

Committer:
Sergunb
Date:
Sat Feb 04 18:15:49 2017 +0000
Revision:
0:8918a71cdbe9
nothing else

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sergunb 0:8918a71cdbe9 1 /**
Sergunb 0:8918a71cdbe9 2 * @file nbns_responder.c
Sergunb 0:8918a71cdbe9 3 * @brief NBNS responder (NetBIOS Name Service)
Sergunb 0:8918a71cdbe9 4 *
Sergunb 0:8918a71cdbe9 5 * @section License
Sergunb 0:8918a71cdbe9 6 *
Sergunb 0:8918a71cdbe9 7 * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
Sergunb 0:8918a71cdbe9 8 *
Sergunb 0:8918a71cdbe9 9 * This file is part of CycloneTCP Open.
Sergunb 0:8918a71cdbe9 10 *
Sergunb 0:8918a71cdbe9 11 * This program is free software; you can redistribute it and/or
Sergunb 0:8918a71cdbe9 12 * modify it under the terms of the GNU General Public License
Sergunb 0:8918a71cdbe9 13 * as published by the Free Software Foundation; either version 2
Sergunb 0:8918a71cdbe9 14 * of the License, or (at your option) any later version.
Sergunb 0:8918a71cdbe9 15 *
Sergunb 0:8918a71cdbe9 16 * This program is distributed in the hope that it will be useful,
Sergunb 0:8918a71cdbe9 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
Sergunb 0:8918a71cdbe9 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
Sergunb 0:8918a71cdbe9 19 * GNU General Public License for more details.
Sergunb 0:8918a71cdbe9 20 *
Sergunb 0:8918a71cdbe9 21 * You should have received a copy of the GNU General Public License
Sergunb 0:8918a71cdbe9 22 * along with this program; if not, write to the Free Software Foundation,
Sergunb 0:8918a71cdbe9 23 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Sergunb 0:8918a71cdbe9 24 *
Sergunb 0:8918a71cdbe9 25 * @author Oryx Embedded SARL (www.oryx-embedded.com)
Sergunb 0:8918a71cdbe9 26 * @version 1.7.6
Sergunb 0:8918a71cdbe9 27 **/
Sergunb 0:8918a71cdbe9 28
Sergunb 0:8918a71cdbe9 29 //Switch to the appropriate trace level
Sergunb 0:8918a71cdbe9 30 #define TRACE_LEVEL NBNS_TRACE_LEVEL
Sergunb 0:8918a71cdbe9 31
Sergunb 0:8918a71cdbe9 32 //Dependencies
Sergunb 0:8918a71cdbe9 33 #include "core/net.h"
Sergunb 0:8918a71cdbe9 34 #include "netbios/nbns_responder.h"
Sergunb 0:8918a71cdbe9 35 #include "netbios/nbns_common.h"
Sergunb 0:8918a71cdbe9 36 #include "dns/dns_debug.h"
Sergunb 0:8918a71cdbe9 37 #include "debug.h"
Sergunb 0:8918a71cdbe9 38
Sergunb 0:8918a71cdbe9 39 //Check TCP/IP stack configuration
Sergunb 0:8918a71cdbe9 40 #if (NBNS_RESPONDER_SUPPORT == ENABLED && IPV4_SUPPORT == ENABLED)
Sergunb 0:8918a71cdbe9 41
Sergunb 0:8918a71cdbe9 42
Sergunb 0:8918a71cdbe9 43 /**
Sergunb 0:8918a71cdbe9 44 * @brief Process NBNS query message
Sergunb 0:8918a71cdbe9 45 * @param[in] interface Underlying network interface
Sergunb 0:8918a71cdbe9 46 * @param[in] pseudoHeader UDP pseudo header
Sergunb 0:8918a71cdbe9 47 * @param[in] udpHeader UDP header
Sergunb 0:8918a71cdbe9 48 * @param[in] message Pointer to the NBNS query message
Sergunb 0:8918a71cdbe9 49 * @param[in] length Length of the message
Sergunb 0:8918a71cdbe9 50 **/
Sergunb 0:8918a71cdbe9 51
Sergunb 0:8918a71cdbe9 52 void nbnsProcessQuery(NetInterface *interface, const Ipv4PseudoHeader *pseudoHeader,
Sergunb 0:8918a71cdbe9 53 const UdpHeader *udpHeader, const NbnsHeader *message, size_t length)
Sergunb 0:8918a71cdbe9 54 {
Sergunb 0:8918a71cdbe9 55 size_t pos;
Sergunb 0:8918a71cdbe9 56 DnsQuestion *question;
Sergunb 0:8918a71cdbe9 57
Sergunb 0:8918a71cdbe9 58 //The NBNS query shall contain one question
Sergunb 0:8918a71cdbe9 59 if(ntohs(message->qdcount) != 1)
Sergunb 0:8918a71cdbe9 60 return;
Sergunb 0:8918a71cdbe9 61
Sergunb 0:8918a71cdbe9 62 //Parse NetBIOS name
Sergunb 0:8918a71cdbe9 63 pos = nbnsParseName(message, length, sizeof(DnsHeader), NULL);
Sergunb 0:8918a71cdbe9 64
Sergunb 0:8918a71cdbe9 65 //Invalid name?
Sergunb 0:8918a71cdbe9 66 if(!pos)
Sergunb 0:8918a71cdbe9 67 return;
Sergunb 0:8918a71cdbe9 68 //Malformed NBNS query message?
Sergunb 0:8918a71cdbe9 69 if((pos + sizeof(DnsQuestion)) > length)
Sergunb 0:8918a71cdbe9 70 return;
Sergunb 0:8918a71cdbe9 71
Sergunb 0:8918a71cdbe9 72 //Point to the corresponding entry
Sergunb 0:8918a71cdbe9 73 question = DNS_GET_QUESTION(message, pos);
Sergunb 0:8918a71cdbe9 74
Sergunb 0:8918a71cdbe9 75 //Check the class and the type of the request
Sergunb 0:8918a71cdbe9 76 if(ntohs(question->qclass) != DNS_RR_CLASS_IN)
Sergunb 0:8918a71cdbe9 77 return;
Sergunb 0:8918a71cdbe9 78 if(ntohs(question->qtype) != DNS_RR_TYPE_NB)
Sergunb 0:8918a71cdbe9 79 return;
Sergunb 0:8918a71cdbe9 80
Sergunb 0:8918a71cdbe9 81 //Compare NetBIOS names
Sergunb 0:8918a71cdbe9 82 if(nbnsCompareName(message, length, sizeof(DnsHeader), interface->hostname))
Sergunb 0:8918a71cdbe9 83 {
Sergunb 0:8918a71cdbe9 84 uint16_t destPort;
Sergunb 0:8918a71cdbe9 85 IpAddr destIpAddr;
Sergunb 0:8918a71cdbe9 86
Sergunb 0:8918a71cdbe9 87 //A response packet is always sent to the source UDP port and
Sergunb 0:8918a71cdbe9 88 //source IP address of the request packet
Sergunb 0:8918a71cdbe9 89 destIpAddr.length = sizeof(Ipv4Addr);
Sergunb 0:8918a71cdbe9 90 destIpAddr.ipv4Addr = pseudoHeader->srcAddr;
Sergunb 0:8918a71cdbe9 91
Sergunb 0:8918a71cdbe9 92 //Convert the port number to host byte order
Sergunb 0:8918a71cdbe9 93 destPort = ntohs(udpHeader->srcPort);
Sergunb 0:8918a71cdbe9 94
Sergunb 0:8918a71cdbe9 95 //Send NBNS response
Sergunb 0:8918a71cdbe9 96 nbnsSendResponse(interface, &destIpAddr, destPort, message->id);
Sergunb 0:8918a71cdbe9 97 }
Sergunb 0:8918a71cdbe9 98 }
Sergunb 0:8918a71cdbe9 99
Sergunb 0:8918a71cdbe9 100
Sergunb 0:8918a71cdbe9 101 /**
Sergunb 0:8918a71cdbe9 102 * @brief Send NBNS response message
Sergunb 0:8918a71cdbe9 103 * @param[in] interface Underlying network interface
Sergunb 0:8918a71cdbe9 104 * @param[in] destIpAddr Destination IP address
Sergunb 0:8918a71cdbe9 105 * @param[in] destPort destination port
Sergunb 0:8918a71cdbe9 106 * @param[in] id 16-bit identifier to be used when sending NBNS query
Sergunb 0:8918a71cdbe9 107 **/
Sergunb 0:8918a71cdbe9 108
Sergunb 0:8918a71cdbe9 109 error_t nbnsSendResponse(NetInterface *interface,
Sergunb 0:8918a71cdbe9 110 const IpAddr *destIpAddr, uint16_t destPort, uint16_t id)
Sergunb 0:8918a71cdbe9 111 {
Sergunb 0:8918a71cdbe9 112 error_t error;
Sergunb 0:8918a71cdbe9 113 size_t length;
Sergunb 0:8918a71cdbe9 114 size_t offset;
Sergunb 0:8918a71cdbe9 115 NetBuffer *buffer;
Sergunb 0:8918a71cdbe9 116 NbnsHeader *message;
Sergunb 0:8918a71cdbe9 117 NbnsAddrEntry *addrEntry;
Sergunb 0:8918a71cdbe9 118 DnsResourceRecord *record;
Sergunb 0:8918a71cdbe9 119
Sergunb 0:8918a71cdbe9 120 //Allocate a memory buffer to hold the NBNS response message
Sergunb 0:8918a71cdbe9 121 buffer = udpAllocBuffer(DNS_MESSAGE_MAX_SIZE, &offset);
Sergunb 0:8918a71cdbe9 122 //Failed to allocate buffer?
Sergunb 0:8918a71cdbe9 123 if(buffer == NULL)
Sergunb 0:8918a71cdbe9 124 return ERROR_OUT_OF_MEMORY;
Sergunb 0:8918a71cdbe9 125
Sergunb 0:8918a71cdbe9 126 //Point to the NBNS header
Sergunb 0:8918a71cdbe9 127 message = netBufferAt(buffer, offset);
Sergunb 0:8918a71cdbe9 128
Sergunb 0:8918a71cdbe9 129 //Take the identifier from the query message
Sergunb 0:8918a71cdbe9 130 message->id = id;
Sergunb 0:8918a71cdbe9 131
Sergunb 0:8918a71cdbe9 132 //Format NBNS response header
Sergunb 0:8918a71cdbe9 133 message->qr = 1;
Sergunb 0:8918a71cdbe9 134 message->opcode = DNS_OPCODE_QUERY;
Sergunb 0:8918a71cdbe9 135 message->aa = 1;
Sergunb 0:8918a71cdbe9 136 message->tc = 0;
Sergunb 0:8918a71cdbe9 137 message->rd = 1;
Sergunb 0:8918a71cdbe9 138 message->ra = 1;
Sergunb 0:8918a71cdbe9 139 message->z = 0;
Sergunb 0:8918a71cdbe9 140 message->b = 0;
Sergunb 0:8918a71cdbe9 141 message->rcode = DNS_RCODE_NO_ERROR;
Sergunb 0:8918a71cdbe9 142
Sergunb 0:8918a71cdbe9 143 //The NBNS response contains 1 answer resource record
Sergunb 0:8918a71cdbe9 144 message->qdcount = 0;
Sergunb 0:8918a71cdbe9 145 message->ancount = HTONS(1);
Sergunb 0:8918a71cdbe9 146 message->nscount = 0;
Sergunb 0:8918a71cdbe9 147 message->arcount = 0;
Sergunb 0:8918a71cdbe9 148
Sergunb 0:8918a71cdbe9 149 //NBNS response message length
Sergunb 0:8918a71cdbe9 150 length = sizeof(DnsHeader);
Sergunb 0:8918a71cdbe9 151
Sergunb 0:8918a71cdbe9 152 //Encode the host name using the NBNS name notation
Sergunb 0:8918a71cdbe9 153 length += nbnsEncodeName(interface->hostname, (uint8_t *) message + length);
Sergunb 0:8918a71cdbe9 154
Sergunb 0:8918a71cdbe9 155 //Point to the corresponding resource record
Sergunb 0:8918a71cdbe9 156 record = DNS_GET_RESOURCE_RECORD(message, length);
Sergunb 0:8918a71cdbe9 157 //Fill in resource record
Sergunb 0:8918a71cdbe9 158 record->rtype = HTONS(DNS_RR_TYPE_NB);
Sergunb 0:8918a71cdbe9 159 record->rclass = HTONS(DNS_RR_CLASS_IN);
Sergunb 0:8918a71cdbe9 160 record->ttl = HTONL(NBNS_DEFAULT_RESOURCE_RECORD_TTL);
Sergunb 0:8918a71cdbe9 161 record->rdlength = HTONS(sizeof(NbnsAddrEntry));
Sergunb 0:8918a71cdbe9 162
Sergunb 0:8918a71cdbe9 163 //Point to the address entry array
Sergunb 0:8918a71cdbe9 164 addrEntry = (NbnsAddrEntry *) record->rdata;
Sergunb 0:8918a71cdbe9 165 //Fill in address entry
Sergunb 0:8918a71cdbe9 166 addrEntry->flags = HTONS(NBNS_G_UNIQUE | NBNS_ONT_BNODE);
Sergunb 0:8918a71cdbe9 167 addrEntry->addr = interface->ipv4Context.addr;
Sergunb 0:8918a71cdbe9 168
Sergunb 0:8918a71cdbe9 169 //Update the length of the NBNS response message
Sergunb 0:8918a71cdbe9 170 length += sizeof(DnsResourceRecord) + sizeof(NbnsAddrEntry);
Sergunb 0:8918a71cdbe9 171
Sergunb 0:8918a71cdbe9 172 //Adjust the length of the multi-part buffer
Sergunb 0:8918a71cdbe9 173 netBufferSetLength(buffer, offset + length);
Sergunb 0:8918a71cdbe9 174
Sergunb 0:8918a71cdbe9 175 //Debug message
Sergunb 0:8918a71cdbe9 176 TRACE_INFO("Sending NBNS message (%" PRIuSIZE " bytes)...\r\n", length);
Sergunb 0:8918a71cdbe9 177 //Dump message
Sergunb 0:8918a71cdbe9 178 dnsDumpMessage((DnsHeader *) message, length);
Sergunb 0:8918a71cdbe9 179
Sergunb 0:8918a71cdbe9 180 //A response packet is always sent to the source UDP port and
Sergunb 0:8918a71cdbe9 181 //source IP address of the request packet
Sergunb 0:8918a71cdbe9 182 error = udpSendDatagramEx(interface, NBNS_PORT, destIpAddr,
Sergunb 0:8918a71cdbe9 183 destPort, buffer, offset, IPV4_DEFAULT_TTL);
Sergunb 0:8918a71cdbe9 184
Sergunb 0:8918a71cdbe9 185 //Free previously allocated memory
Sergunb 0:8918a71cdbe9 186 netBufferFree(buffer);
Sergunb 0:8918a71cdbe9 187 //Return status code
Sergunb 0:8918a71cdbe9 188 return error;
Sergunb 0:8918a71cdbe9 189 }
Sergunb 0:8918a71cdbe9 190
Sergunb 0:8918a71cdbe9 191 #endif
Sergunb 0:8918a71cdbe9 192