1292 lines
45 KiB
C
1292 lines
45 KiB
C
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#ifdef _WIN32
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#define _CRT_SECURE_NO_WARNINGS 1
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#endif
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#include <stdio.h>
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#include <errno.h>
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#include <signal.h>
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#ifdef _WIN32
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#include <winsock2.h>
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#include <iphlpapi.h>
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#include <ws2tcpip.h>
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#define sleep(x) Sleep(x * 1000)
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#else
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#include <netdb.h>
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#include <ifaddrs.h>
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#include <net/if.h>
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#include <sys/time.h>
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#endif
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// Alias some things to simulate recieving data to fuzz library
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#if defined(MDNS_FUZZING)
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#define recvfrom(sock, buffer, capacity, flags, src_addr, addrlen) ((mdns_ssize_t)capacity)
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#define printf
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#endif
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#include "mdns.h"
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#if defined(MDNS_FUZZING)
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#undef recvfrom
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#endif
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static char addrbuffer[64];
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static char entrybuffer[256];
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static char namebuffer[256];
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static char sendbuffer[1024];
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static mdns_record_txt_t txtbuffer[128];
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static struct sockaddr_in service_address_ipv4;
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static struct sockaddr_in6 service_address_ipv6;
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static int has_ipv4;
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static int has_ipv6;
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volatile sig_atomic_t running = 1;
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// Data for our service including the mDNS records
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typedef struct {
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mdns_string_t service;
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mdns_string_t hostname;
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mdns_string_t service_instance;
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mdns_string_t hostname_qualified;
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struct sockaddr_in address_ipv4;
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struct sockaddr_in6 address_ipv6;
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int port;
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mdns_record_t record_ptr;
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mdns_record_t record_srv;
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mdns_record_t record_a;
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mdns_record_t record_aaaa;
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mdns_record_t txt_record[2];
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} service_t;
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typedef struct
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{
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int port;
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char ip[32];
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char domain[32];
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}server_info_t;
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static mdns_string_t
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ipv4_address_to_string(char* buffer, size_t capacity, const struct sockaddr_in* addr,
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size_t addrlen) {
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char host[NI_MAXHOST] = {0};
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char service[NI_MAXSERV] = {0};
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int ret = getnameinfo((const struct sockaddr*)addr, (socklen_t)addrlen, host, NI_MAXHOST,
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service, NI_MAXSERV, NI_NUMERICSERV | NI_NUMERICHOST);
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int len = 0;
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if (ret == 0) {
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if (addr->sin_port != 0)
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len = snprintf(buffer, capacity, "%s:%s", host, service);
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else
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len = snprintf(buffer, capacity, "%s", host);
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}
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if (len >= (int)capacity)
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len = (int)capacity - 1;
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mdns_string_t str;
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str.str = buffer;
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str.length = len;
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return str;
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}
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static mdns_string_t
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ipv6_address_to_string(char* buffer, size_t capacity, const struct sockaddr_in6* addr,
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size_t addrlen) {
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char host[NI_MAXHOST] = {0};
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char service[NI_MAXSERV] = {0};
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int ret = getnameinfo((const struct sockaddr*)addr, (socklen_t)addrlen, host, NI_MAXHOST,
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service, NI_MAXSERV, NI_NUMERICSERV | NI_NUMERICHOST);
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int len = 0;
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if (ret == 0) {
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if (addr->sin6_port != 0)
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len = snprintf(buffer, capacity, "[%s]:%s", host, service);
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else
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len = snprintf(buffer, capacity, "%s", host);
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}
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if (len >= (int)capacity)
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len = (int)capacity - 1;
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mdns_string_t str;
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str.str = buffer;
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str.length = len;
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return str;
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}
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static mdns_string_t
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ip_address_to_string(char* buffer, size_t capacity, const struct sockaddr* addr, size_t addrlen) {
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if (addr->sa_family == AF_INET6)
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return ipv6_address_to_string(buffer, capacity, (const struct sockaddr_in6*)addr, addrlen);
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return ipv4_address_to_string(buffer, capacity, (const struct sockaddr_in*)addr, addrlen);
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}
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// Callback handling parsing answers to queries sent
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static int
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query_callback(int sock, const struct sockaddr* from, size_t addrlen, mdns_entry_type_t entry,
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uint16_t query_id, uint16_t rtype, uint16_t rclass, uint32_t ttl, const void* data,
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size_t size, size_t name_offset, size_t name_length, size_t record_offset,
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size_t record_length, void* user_data) {
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(void)sizeof(sock);
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(void)sizeof(query_id);
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(void)sizeof(name_length);
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(void)sizeof(user_data);
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server_info_t *server_info = (server_info_t *)user_data;
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mdns_string_t fromaddrstr = ip_address_to_string(addrbuffer, sizeof(addrbuffer), from, addrlen);
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const char* entrytype = (entry == MDNS_ENTRYTYPE_ANSWER) ?
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"answer" :
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((entry == MDNS_ENTRYTYPE_AUTHORITY) ? "authority" : "additional");
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mdns_string_t entrystr =
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mdns_string_extract(data, size, &name_offset, entrybuffer, sizeof(entrybuffer));
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if (rtype == MDNS_RECORDTYPE_PTR) {
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mdns_string_t namestr = mdns_record_parse_ptr(data, size, record_offset, record_length,
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namebuffer, sizeof(namebuffer));
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printf("%.*s : %s %.*s PTR %.*s rclass 0x%x ttl %u length %d\n",
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MDNS_STRING_FORMAT(fromaddrstr), entrytype, MDNS_STRING_FORMAT(entrystr),
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MDNS_STRING_FORMAT(namestr), rclass, ttl, (int)record_length);
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} else if (rtype == MDNS_RECORDTYPE_SRV) {
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mdns_record_srv_t srv = mdns_record_parse_srv(data, size, record_offset, record_length,
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namebuffer, sizeof(namebuffer));
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server_info->port = srv.port;
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memcpy(server_info->domain, srv.name.str, srv.name.length - 1);
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printf("%.*s : %s %.*s SRV %.*s priority %d weight %d port %d\n",
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MDNS_STRING_FORMAT(fromaddrstr), entrytype, MDNS_STRING_FORMAT(entrystr),
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MDNS_STRING_FORMAT(srv.name), srv.priority, srv.weight, srv.port);
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} else if (rtype == MDNS_RECORDTYPE_A) {
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struct sockaddr_in addr;
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mdns_record_parse_a(data, size, record_offset, record_length, &addr);
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mdns_string_t addrstr =
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ipv4_address_to_string(namebuffer, sizeof(namebuffer), &addr, sizeof(addr));
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memcpy(server_info->ip, addrstr.str, addrstr.length);
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printf("%.*s : %s %.*s A %.*s\n", MDNS_STRING_FORMAT(fromaddrstr), entrytype,
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MDNS_STRING_FORMAT(entrystr), MDNS_STRING_FORMAT(addrstr));
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} else if (rtype == MDNS_RECORDTYPE_AAAA) {
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struct sockaddr_in6 addr;
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mdns_record_parse_aaaa(data, size, record_offset, record_length, &addr);
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mdns_string_t addrstr =
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ipv6_address_to_string(namebuffer, sizeof(namebuffer), &addr, sizeof(addr));
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printf("%.*s : %s %.*s AAAA %.*s\n", MDNS_STRING_FORMAT(fromaddrstr), entrytype,
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MDNS_STRING_FORMAT(entrystr), MDNS_STRING_FORMAT(addrstr));
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} else if (rtype == MDNS_RECORDTYPE_TXT) {
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size_t parsed = mdns_record_parse_txt(data, size, record_offset, record_length, txtbuffer,
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sizeof(txtbuffer) / sizeof(mdns_record_txt_t));
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for (size_t itxt = 0; itxt < parsed; ++itxt) {
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if (txtbuffer[itxt].value.length) {
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printf("%.*s : %s %.*s TXT %.*s = %.*s\n", MDNS_STRING_FORMAT(fromaddrstr),
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entrytype, MDNS_STRING_FORMAT(entrystr),
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MDNS_STRING_FORMAT(txtbuffer[itxt].key),
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MDNS_STRING_FORMAT(txtbuffer[itxt].value));
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} else {
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printf("%.*s : %s %.*s TXT %.*s\n", MDNS_STRING_FORMAT(fromaddrstr), entrytype,
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MDNS_STRING_FORMAT(entrystr), MDNS_STRING_FORMAT(txtbuffer[itxt].key));
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}
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}
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} else {
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printf("%.*s : %s %.*s type %u rclass 0x%x ttl %u length %d\n",
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MDNS_STRING_FORMAT(fromaddrstr), entrytype, MDNS_STRING_FORMAT(entrystr), rtype,
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rclass, ttl, (int)record_length);
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}
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return 0;
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}
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// Callback handling questions incoming on service sockets
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static int
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service_callback(int sock, const struct sockaddr* from, size_t addrlen, mdns_entry_type_t entry,
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uint16_t query_id, uint16_t rtype, uint16_t rclass, uint32_t ttl, const void* data,
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size_t size, size_t name_offset, size_t name_length, size_t record_offset,
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size_t record_length, void* user_data) {
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(void)sizeof(ttl);
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if (entry != MDNS_ENTRYTYPE_QUESTION)
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return 0;
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const char dns_sd[] = "_services._dns-sd._udp.local.";
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const service_t* service = (const service_t*)user_data;
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mdns_string_t fromaddrstr = ip_address_to_string(addrbuffer, sizeof(addrbuffer), from, addrlen);
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size_t offset = name_offset;
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mdns_string_t name = mdns_string_extract(data, size, &offset, namebuffer, sizeof(namebuffer));
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const char* record_name = 0;
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if (rtype == MDNS_RECORDTYPE_PTR)
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record_name = "PTR";
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else if (rtype == MDNS_RECORDTYPE_SRV)
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record_name = "SRV";
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else if (rtype == MDNS_RECORDTYPE_A)
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record_name = "A";
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else if (rtype == MDNS_RECORDTYPE_AAAA)
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record_name = "AAAA";
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else if (rtype == MDNS_RECORDTYPE_TXT)
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record_name = "TXT";
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else if (rtype == MDNS_RECORDTYPE_ANY)
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record_name = "ANY";
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else
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return 0;
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//printf("Query ---3--- %s %.*s\n", record_name, MDNS_STRING_FORMAT(name));
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if ((name.length == (sizeof(dns_sd) - 1)) &&
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(strncmp(name.str, dns_sd, sizeof(dns_sd) - 1) == 0)) {
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if ((rtype == MDNS_RECORDTYPE_PTR) || (rtype == MDNS_RECORDTYPE_ANY)) {
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// The PTR query was for the DNS-SD domain, send answer with a PTR record for the
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// service name we advertise, typically on the "<_service-name>._tcp.local." format
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// Answer PTR record reverse mapping "<_service-name>._tcp.local." to
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// "<hostname>.<_service-name>._tcp.local."
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mdns_record_t answer = {
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.name = name, .type = MDNS_RECORDTYPE_PTR, .data.ptr.name = service->service};
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// Send the answer, unicast or multicast depending on flag in query
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uint16_t unicast = (rclass & MDNS_UNICAST_RESPONSE);
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printf(" --> answer %.*s (%s)\n", MDNS_STRING_FORMAT(answer.data.ptr.name),
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(unicast ? "unicast" : "multicast"));
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if (unicast) {
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mdns_query_answer_unicast(sock, from, addrlen, sendbuffer, sizeof(sendbuffer),
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query_id, rtype, name.str, name.length, answer, 0, 0, 0,
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0);
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} else {
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mdns_query_answer_multicast(sock, sendbuffer, sizeof(sendbuffer), answer, 0, 0, 0,
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0);
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}
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}
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} else if ((name.length == service->service.length) &&
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(strncmp(name.str, service->service.str, name.length) == 0)) {
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if ((rtype == MDNS_RECORDTYPE_PTR) || (rtype == MDNS_RECORDTYPE_ANY)) {
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// The PTR query was for our service (usually "<_service-name._tcp.local"), answer a PTR
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// record reverse mapping the queried service name to our service instance name
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// (typically on the "<hostname>.<_service-name>._tcp.local." format), and add
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// additional records containing the SRV record mapping the service instance name to our
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// qualified hostname (typically "<hostname>.local.") and port, as well as any IPv4/IPv6
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// address for the hostname as A/AAAA records, and two test TXT records
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// Answer PTR record reverse mapping "<_service-name>._tcp.local." to
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// "<hostname>.<_service-name>._tcp.local."
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mdns_record_t answer = service->record_ptr;
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mdns_record_t additional[5] = {0};
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size_t additional_count = 0;
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// SRV record mapping "<hostname>.<_service-name>._tcp.local." to
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// "<hostname>.local." with port. Set weight & priority to 0.
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additional[additional_count++] = service->record_srv;
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// A/AAAA records mapping "<hostname>.local." to IPv4/IPv6 addresses
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if (service->address_ipv4.sin_family == AF_INET)
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additional[additional_count++] = service->record_a;
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if (service->address_ipv6.sin6_family == AF_INET6)
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additional[additional_count++] = service->record_aaaa;
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// Add two test TXT records for our service instance name, will be coalesced into
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// one record with both key-value pair strings by the library
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additional[additional_count++] = service->txt_record[0];
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additional[additional_count++] = service->txt_record[1];
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// Send the answer, unicast or multicast depending on flag in query
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uint16_t unicast = (rclass & MDNS_UNICAST_RESPONSE);
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printf(" --> answer %.*s (%s)\n",
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MDNS_STRING_FORMAT(service->record_ptr.data.ptr.name),
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(unicast ? "unicast" : "multicast"));
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if (unicast) {
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mdns_query_answer_unicast(sock, from, addrlen, sendbuffer, sizeof(sendbuffer),
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query_id, rtype, name.str, name.length, answer, 0, 0,
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additional, additional_count);
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} else {
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mdns_query_answer_multicast(sock, sendbuffer, sizeof(sendbuffer), answer, 0, 0,
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additional, additional_count);
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}
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}
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} else if ((name.length == service->service_instance.length) &&
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(strncmp(name.str, service->service_instance.str, name.length) == 0)) {
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if ((rtype == MDNS_RECORDTYPE_SRV) || (rtype == MDNS_RECORDTYPE_ANY)) {
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// The SRV query was for our service instance (usually
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// "<hostname>.<_service-name._tcp.local"), answer a SRV record mapping the service
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// instance name to our qualified hostname (typically "<hostname>.local.") and port, as
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// well as any IPv4/IPv6 address for the hostname as A/AAAA records, and two test TXT
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// records
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// Answer PTR record reverse mapping "<_service-name>._tcp.local." to
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// "<hostname>.<_service-name>._tcp.local."
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mdns_record_t answer = service->record_srv;
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mdns_record_t additional[5] = {0};
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size_t additional_count = 0;
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// A/AAAA records mapping "<hostname>.local." to IPv4/IPv6 addresses
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if (service->address_ipv4.sin_family == AF_INET)
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additional[additional_count++] = service->record_a;
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if (service->address_ipv6.sin6_family == AF_INET6)
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additional[additional_count++] = service->record_aaaa;
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// Add two test TXT records for our service instance name, will be coalesced into
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// one record with both key-value pair strings by the library
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additional[additional_count++] = service->txt_record[0];
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additional[additional_count++] = service->txt_record[1];
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// Send the answer, unicast or multicast depending on flag in query
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uint16_t unicast = (rclass & MDNS_UNICAST_RESPONSE);
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printf(" --> answer %.*s port %d (%s)\n",
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MDNS_STRING_FORMAT(service->record_srv.data.srv.name), service->port,
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(unicast ? "unicast" : "multicast"));
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if (unicast) {
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mdns_query_answer_unicast(sock, from, addrlen, sendbuffer, sizeof(sendbuffer),
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query_id, rtype, name.str, name.length, answer, 0, 0,
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additional, additional_count);
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} else {
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mdns_query_answer_multicast(sock, sendbuffer, sizeof(sendbuffer), answer, 0, 0,
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additional, additional_count);
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}
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}
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} else if ((name.length == service->hostname_qualified.length) &&
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(strncmp(name.str, service->hostname_qualified.str, name.length) == 0)) {
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if (((rtype == MDNS_RECORDTYPE_A) || (rtype == MDNS_RECORDTYPE_ANY)) &&
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(service->address_ipv4.sin_family == AF_INET)) {
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// The A query was for our qualified hostname (typically "<hostname>.local.") and we
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// have an IPv4 address, answer with an A record mappiing the hostname to an IPv4
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// address, as well as any IPv6 address for the hostname, and two test TXT records
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// Answer A records mapping "<hostname>.local." to IPv4 address
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mdns_record_t answer = service->record_a;
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mdns_record_t additional[5] = {0};
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size_t additional_count = 0;
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// AAAA record mapping "<hostname>.local." to IPv6 addresses
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if (service->address_ipv6.sin6_family == AF_INET6)
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additional[additional_count++] = service->record_aaaa;
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// Add two test TXT records for our service instance name, will be coalesced into
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// one record with both key-value pair strings by the library
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additional[additional_count++] = service->txt_record[0];
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additional[additional_count++] = service->txt_record[1];
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// Send the answer, unicast or multicast depending on flag in query
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uint16_t unicast = (rclass & MDNS_UNICAST_RESPONSE);
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mdns_string_t addrstr = ip_address_to_string(
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addrbuffer, sizeof(addrbuffer), (struct sockaddr*)&service->record_a.data.a.addr,
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sizeof(service->record_a.data.a.addr));
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printf(" --> answer %.*s IPv4 %.*s (%s)\n", MDNS_STRING_FORMAT(service->record_a.name),
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MDNS_STRING_FORMAT(addrstr), (unicast ? "unicast" : "multicast"));
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if (unicast) {
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mdns_query_answer_unicast(sock, from, addrlen, sendbuffer, sizeof(sendbuffer),
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query_id, rtype, name.str, name.length, answer, 0, 0,
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additional, additional_count);
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} else {
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mdns_query_answer_multicast(sock, sendbuffer, sizeof(sendbuffer), answer, 0, 0,
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additional, additional_count);
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}
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} else if (((rtype == MDNS_RECORDTYPE_AAAA) || (rtype == MDNS_RECORDTYPE_ANY)) &&
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(service->address_ipv6.sin6_family == AF_INET6)) {
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// The AAAA query was for our qualified hostname (typically "<hostname>.local.") and we
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// have an IPv6 address, answer with an AAAA record mappiing the hostname to an IPv6
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// address, as well as any IPv4 address for the hostname, and two test TXT records
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// Answer AAAA records mapping "<hostname>.local." to IPv6 address
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mdns_record_t answer = service->record_aaaa;
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mdns_record_t additional[5] = {0};
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size_t additional_count = 0;
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// A record mapping "<hostname>.local." to IPv4 addresses
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if (service->address_ipv4.sin_family == AF_INET)
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additional[additional_count++] = service->record_a;
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// Add two test TXT records for our service instance name, will be coalesced into
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// one record with both key-value pair strings by the library
|
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additional[additional_count++] = service->txt_record[0];
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additional[additional_count++] = service->txt_record[1];
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// Send the answer, unicast or multicast depending on flag in query
|
|
uint16_t unicast = (rclass & MDNS_UNICAST_RESPONSE);
|
|
mdns_string_t addrstr =
|
|
ip_address_to_string(addrbuffer, sizeof(addrbuffer),
|
|
(struct sockaddr*)&service->record_aaaa.data.aaaa.addr,
|
|
sizeof(service->record_aaaa.data.aaaa.addr));
|
|
printf(" --> answer %.*s IPv6 %.*s (%s)\n",
|
|
MDNS_STRING_FORMAT(service->record_aaaa.name), MDNS_STRING_FORMAT(addrstr),
|
|
(unicast ? "unicast" : "multicast"));
|
|
|
|
if (unicast) {
|
|
mdns_query_answer_unicast(sock, from, addrlen, sendbuffer, sizeof(sendbuffer),
|
|
query_id, rtype, name.str, name.length, answer, 0, 0,
|
|
additional, additional_count);
|
|
} else {
|
|
mdns_query_answer_multicast(sock, sendbuffer, sizeof(sendbuffer), answer, 0, 0,
|
|
additional, additional_count);
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// Callback handling questions and answers dump
|
|
static int
|
|
dump_callback(int sock, const struct sockaddr* from, size_t addrlen, mdns_entry_type_t entry,
|
|
uint16_t query_id, uint16_t rtype, uint16_t rclass, uint32_t ttl, const void* data,
|
|
size_t size, size_t name_offset, size_t name_length, size_t record_offset,
|
|
size_t record_length, void* user_data) {
|
|
mdns_string_t fromaddrstr = ip_address_to_string(addrbuffer, sizeof(addrbuffer), from, addrlen);
|
|
|
|
size_t offset = name_offset;
|
|
mdns_string_t name = mdns_string_extract(data, size, &offset, namebuffer, sizeof(namebuffer));
|
|
|
|
const char* record_name = 0;
|
|
if (rtype == MDNS_RECORDTYPE_PTR)
|
|
record_name = "PTR";
|
|
else if (rtype == MDNS_RECORDTYPE_SRV)
|
|
record_name = "SRV";
|
|
else if (rtype == MDNS_RECORDTYPE_A)
|
|
record_name = "A";
|
|
else if (rtype == MDNS_RECORDTYPE_AAAA)
|
|
record_name = "AAAA";
|
|
else if (rtype == MDNS_RECORDTYPE_TXT)
|
|
record_name = "TXT";
|
|
else if (rtype == MDNS_RECORDTYPE_ANY)
|
|
record_name = "ANY";
|
|
else
|
|
record_name = "<UNKNOWN>";
|
|
|
|
const char* entry_type = "Question";
|
|
if (entry == MDNS_ENTRYTYPE_ANSWER)
|
|
entry_type = "Answer";
|
|
else if (entry == MDNS_ENTRYTYPE_AUTHORITY)
|
|
entry_type = "Authority";
|
|
else if (entry == MDNS_ENTRYTYPE_ADDITIONAL)
|
|
entry_type = "Additional";
|
|
|
|
printf("%.*s: %s %s %.*s rclass 0x%x ttl %u\n", MDNS_STRING_FORMAT(fromaddrstr), entry_type,
|
|
record_name, MDNS_STRING_FORMAT(name), (unsigned int)rclass, ttl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
// Open sockets for sending one-shot multicast queries from an ephemeral port
|
|
static int
|
|
open_client_sockets(int* sockets, int max_sockets, int port) {
|
|
// When sending, each socket can only send to one network interface
|
|
// Thus we need to open one socket for each interface and address family
|
|
int num_sockets = 0;
|
|
|
|
#ifdef _WIN32
|
|
|
|
IP_ADAPTER_ADDRESSES* adapter_address = 0;
|
|
ULONG address_size = 8000;
|
|
unsigned int ret;
|
|
unsigned int num_retries = 4;
|
|
do {
|
|
adapter_address = (IP_ADAPTER_ADDRESSES*)malloc(address_size);
|
|
ret = GetAdaptersAddresses(AF_UNSPEC, GAA_FLAG_SKIP_MULTICAST | GAA_FLAG_SKIP_ANYCAST, 0,
|
|
adapter_address, &address_size);
|
|
if (ret == ERROR_BUFFER_OVERFLOW) {
|
|
free(adapter_address);
|
|
adapter_address = 0;
|
|
address_size *= 2;
|
|
} else {
|
|
break;
|
|
}
|
|
} while (num_retries-- > 0);
|
|
|
|
if (!adapter_address || (ret != NO_ERROR)) {
|
|
free(adapter_address);
|
|
printf("Failed to get network adapter addresses\n");
|
|
return num_sockets;
|
|
}
|
|
|
|
int first_ipv4 = 1;
|
|
int first_ipv6 = 1;
|
|
for (PIP_ADAPTER_ADDRESSES adapter = adapter_address; adapter; adapter = adapter->Next) {
|
|
if (adapter->TunnelType == TUNNEL_TYPE_TEREDO)
|
|
continue;
|
|
if (adapter->OperStatus != IfOperStatusUp)
|
|
continue;
|
|
|
|
for (IP_ADAPTER_UNICAST_ADDRESS* unicast = adapter->FirstUnicastAddress; unicast;
|
|
unicast = unicast->Next) {
|
|
if (unicast->Address.lpSockaddr->sa_family == AF_INET) {
|
|
struct sockaddr_in* saddr = (struct sockaddr_in*)unicast->Address.lpSockaddr;
|
|
if ((saddr->sin_addr.S_un.S_un_b.s_b1 != 127) ||
|
|
(saddr->sin_addr.S_un.S_un_b.s_b2 != 0) ||
|
|
(saddr->sin_addr.S_un.S_un_b.s_b3 != 0) ||
|
|
(saddr->sin_addr.S_un.S_un_b.s_b4 != 1)) {
|
|
int log_addr = 0;
|
|
if (first_ipv4) {
|
|
service_address_ipv4 = *saddr;
|
|
first_ipv4 = 0;
|
|
log_addr = 1;
|
|
}
|
|
has_ipv4 = 1;
|
|
if (num_sockets < max_sockets) {
|
|
saddr->sin_port = htons((unsigned short)port);
|
|
int sock = mdns_socket_open_ipv4(saddr);
|
|
if (sock >= 0) {
|
|
sockets[num_sockets++] = sock;
|
|
log_addr = 1;
|
|
} else {
|
|
log_addr = 0;
|
|
}
|
|
}
|
|
if (log_addr) {
|
|
char buffer[128];
|
|
mdns_string_t addr = ipv4_address_to_string(buffer, sizeof(buffer), saddr,
|
|
sizeof(struct sockaddr_in));
|
|
printf("Local IPv4 address: %.*s\n", MDNS_STRING_FORMAT(addr));
|
|
}
|
|
}
|
|
} else if (unicast->Address.lpSockaddr->sa_family == AF_INET6) {
|
|
struct sockaddr_in6* saddr = (struct sockaddr_in6*)unicast->Address.lpSockaddr;
|
|
// Ignore link-local addresses
|
|
if (saddr->sin6_scope_id)
|
|
continue;
|
|
static const unsigned char localhost[] = {0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 1};
|
|
static const unsigned char localhost_mapped[] = {0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0xff, 0xff, 0x7f, 0, 0, 1};
|
|
if ((unicast->DadState == NldsPreferred) &&
|
|
memcmp(saddr->sin6_addr.s6_addr, localhost, 16) &&
|
|
memcmp(saddr->sin6_addr.s6_addr, localhost_mapped, 16)) {
|
|
int log_addr = 0;
|
|
if (first_ipv6) {
|
|
service_address_ipv6 = *saddr;
|
|
first_ipv6 = 0;
|
|
log_addr = 1;
|
|
}
|
|
has_ipv6 = 1;
|
|
if (num_sockets < max_sockets) {
|
|
saddr->sin6_port = htons((unsigned short)port);
|
|
int sock = mdns_socket_open_ipv6(saddr);
|
|
if (sock >= 0) {
|
|
sockets[num_sockets++] = sock;
|
|
log_addr = 1;
|
|
} else {
|
|
log_addr = 0;
|
|
}
|
|
}
|
|
if (log_addr) {
|
|
char buffer[128];
|
|
mdns_string_t addr = ipv6_address_to_string(buffer, sizeof(buffer), saddr,
|
|
sizeof(struct sockaddr_in6));
|
|
printf("Local IPv6 address: %.*s\n", MDNS_STRING_FORMAT(addr));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
free(adapter_address);
|
|
|
|
#else
|
|
|
|
struct ifaddrs* ifaddr = 0;
|
|
struct ifaddrs* ifa = 0;
|
|
|
|
if (getifaddrs(&ifaddr) < 0)
|
|
printf("Unable to get interface addresses\n");
|
|
|
|
int first_ipv4 = 1;
|
|
int first_ipv6 = 1;
|
|
for (ifa = ifaddr; ifa; ifa = ifa->ifa_next) {
|
|
if (!ifa->ifa_addr)
|
|
continue;
|
|
if (!(ifa->ifa_flags & IFF_UP) || !(ifa->ifa_flags & IFF_MULTICAST))
|
|
continue;
|
|
if ((ifa->ifa_flags & IFF_LOOPBACK) || (ifa->ifa_flags & IFF_POINTOPOINT))
|
|
continue;
|
|
|
|
if (ifa->ifa_addr->sa_family == AF_INET) {
|
|
struct sockaddr_in* saddr = (struct sockaddr_in*)ifa->ifa_addr;
|
|
if (saddr->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) {
|
|
int log_addr = 0;
|
|
if (first_ipv4) {
|
|
service_address_ipv4 = *saddr;
|
|
first_ipv4 = 0;
|
|
log_addr = 1;
|
|
}
|
|
has_ipv4 = 1;
|
|
if (num_sockets < max_sockets) {
|
|
saddr->sin_port = htons(port);
|
|
int sock = mdns_socket_open_ipv4(saddr);
|
|
if (sock >= 0) {
|
|
sockets[num_sockets++] = sock;
|
|
log_addr = 1;
|
|
} else {
|
|
log_addr = 0;
|
|
}
|
|
}
|
|
if (log_addr) {
|
|
char buffer[128];
|
|
mdns_string_t addr = ipv4_address_to_string(buffer, sizeof(buffer), saddr,
|
|
sizeof(struct sockaddr_in));
|
|
printf("Local IPv4 address: %.*s\n", MDNS_STRING_FORMAT(addr));
|
|
}
|
|
}
|
|
} else if (ifa->ifa_addr->sa_family == AF_INET6) {
|
|
struct sockaddr_in6* saddr = (struct sockaddr_in6*)ifa->ifa_addr;
|
|
// Ignore link-local addresses
|
|
if (saddr->sin6_scope_id)
|
|
continue;
|
|
static const unsigned char localhost[] = {0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 1};
|
|
static const unsigned char localhost_mapped[] = {0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0xff, 0xff, 0x7f, 0, 0, 1};
|
|
if (memcmp(saddr->sin6_addr.s6_addr, localhost, 16) &&
|
|
memcmp(saddr->sin6_addr.s6_addr, localhost_mapped, 16)) {
|
|
int log_addr = 0;
|
|
if (first_ipv6) {
|
|
service_address_ipv6 = *saddr;
|
|
first_ipv6 = 0;
|
|
log_addr = 1;
|
|
}
|
|
has_ipv6 = 1;
|
|
if (num_sockets < max_sockets) {
|
|
saddr->sin6_port = htons(port);
|
|
int sock = mdns_socket_open_ipv6(saddr);
|
|
if (sock >= 0) {
|
|
sockets[num_sockets++] = sock;
|
|
log_addr = 1;
|
|
} else {
|
|
log_addr = 0;
|
|
}
|
|
}
|
|
if (log_addr) {
|
|
char buffer[128];
|
|
mdns_string_t addr = ipv6_address_to_string(buffer, sizeof(buffer), saddr,
|
|
sizeof(struct sockaddr_in6));
|
|
printf("Local IPv6 address: %.*s\n", MDNS_STRING_FORMAT(addr));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
freeifaddrs(ifaddr);
|
|
|
|
#endif
|
|
|
|
return num_sockets;
|
|
}
|
|
|
|
// Open sockets to listen to incoming mDNS queries on port 5353
|
|
static int
|
|
open_service_sockets(int* sockets, int max_sockets) {
|
|
// When recieving, each socket can recieve data from all network interfaces
|
|
// Thus we only need to open one socket for each address family
|
|
int num_sockets = 0;
|
|
|
|
// Call the client socket function to enumerate and get local addresses,
|
|
// but not open the actual sockets
|
|
open_client_sockets(0, 0, 0);
|
|
|
|
if (num_sockets < max_sockets) {
|
|
struct sockaddr_in sock_addr;
|
|
memset(&sock_addr, 0, sizeof(struct sockaddr_in));
|
|
sock_addr.sin_family = AF_INET;
|
|
#ifdef _WIN32
|
|
sock_addr.sin_addr = in4addr_any;
|
|
#else
|
|
sock_addr.sin_addr.s_addr = INADDR_ANY;
|
|
#endif
|
|
sock_addr.sin_port = htons(MDNS_PORT);
|
|
#ifdef __APPLE__
|
|
sock_addr.sin_len = sizeof(struct sockaddr_in);
|
|
#endif
|
|
int sock = mdns_socket_open_ipv4(&sock_addr);
|
|
if (sock >= 0) {
|
|
sockets[num_sockets++] = sock;
|
|
printf("IPv4 socket opened successfully on port %d\n", MDNS_PORT);
|
|
}
|
|
else {
|
|
printf("Failed to open IPv4 socket on port %d\n", MDNS_PORT);
|
|
}
|
|
}
|
|
|
|
if (num_sockets < max_sockets) {
|
|
struct sockaddr_in6 sock_addr;
|
|
memset(&sock_addr, 0, sizeof(struct sockaddr_in6));
|
|
sock_addr.sin6_family = AF_INET6;
|
|
sock_addr.sin6_addr = in6addr_any;
|
|
sock_addr.sin6_port = htons(MDNS_PORT);
|
|
#ifdef __APPLE__
|
|
sock_addr.sin6_len = sizeof(struct sockaddr_in6);
|
|
#endif
|
|
int sock = mdns_socket_open_ipv6(&sock_addr);
|
|
if (sock >= 0){
|
|
sockets[num_sockets++] = sock;
|
|
printf("IPv6 socket opened successfully on port %d\n", MDNS_PORT);
|
|
}
|
|
else {
|
|
printf("Failed to open IPv6 socket on port %d\n", MDNS_PORT);
|
|
}
|
|
}
|
|
|
|
return num_sockets;
|
|
}
|
|
|
|
// Send a DNS-SD query
|
|
static int
|
|
send_dns_sd(void) {
|
|
int sockets[32];
|
|
int num_sockets = open_client_sockets(sockets, sizeof(sockets) / sizeof(sockets[0]), 0);
|
|
if (num_sockets <= 0) {
|
|
printf("Failed to open any client sockets\n");
|
|
return -1;
|
|
}
|
|
printf("Opened %d socket%s for DNS-SD\n", num_sockets, num_sockets > 1 ? "s" : "");
|
|
|
|
printf("Sending DNS-SD discovery\n");
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (mdns_discovery_send(sockets[isock]))
|
|
printf("Failed to send DNS-DS discovery: %s\n", strerror(errno));
|
|
}
|
|
|
|
size_t capacity = 2048;
|
|
void* buffer = malloc(capacity);
|
|
void* user_data = 0;
|
|
size_t records;
|
|
|
|
// This is a simple implementation that loops for 5 seconds or as long as we get replies
|
|
int res;
|
|
printf("Reading DNS-SD replies\n");
|
|
do {
|
|
struct timeval timeout;
|
|
timeout.tv_sec = 5;
|
|
timeout.tv_usec = 0;
|
|
|
|
int nfds = 0;
|
|
fd_set readfs;
|
|
FD_ZERO(&readfs);
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (sockets[isock] >= nfds)
|
|
nfds = sockets[isock] + 1;
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
|
|
records = 0;
|
|
res = select(nfds, &readfs, 0, 0, &timeout);
|
|
if (res > 0) {
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (FD_ISSET(sockets[isock], &readfs)) {
|
|
records += mdns_discovery_recv(sockets[isock], buffer, capacity, query_callback,
|
|
user_data);
|
|
}
|
|
}
|
|
}
|
|
} while (res > 0);
|
|
|
|
free(buffer);
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_socket_close(sockets[isock]);
|
|
printf("Closed socket%s\n", num_sockets ? "s" : "");
|
|
|
|
return 0;
|
|
}
|
|
|
|
// Send a mDNS query
|
|
static int
|
|
send_mdns_query(mdns_query_t* query, size_t count, void* user_data) {
|
|
int sockets[32];
|
|
int query_id[32];
|
|
int num_sockets = open_client_sockets(sockets, sizeof(sockets) / sizeof(sockets[0]), 0);
|
|
if (num_sockets <= 0) {
|
|
printf("Failed to open any client sockets\n");
|
|
return -1;
|
|
}
|
|
printf("Opened %d socket%s for mDNS query\n", num_sockets, num_sockets ? "s" : "");
|
|
|
|
size_t capacity = 2048;
|
|
void* buffer = malloc(capacity);
|
|
//void* user_data = 0;
|
|
|
|
printf("Sending mDNS query");
|
|
for (size_t iq = 0; iq < count; ++iq) {
|
|
const char* record_name = "PTR";
|
|
if (query[iq].type == MDNS_RECORDTYPE_SRV)
|
|
record_name = "SRV";
|
|
else if (query[iq].type == MDNS_RECORDTYPE_A)
|
|
record_name = "A";
|
|
else if (query[iq].type == MDNS_RECORDTYPE_AAAA)
|
|
record_name = "AAAA";
|
|
else
|
|
query[iq].type = MDNS_RECORDTYPE_PTR;
|
|
printf(" : %s %s", query[iq].name, record_name);
|
|
}
|
|
printf("\n");
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
query_id[isock] =
|
|
mdns_multiquery_send(sockets[isock], query, count, buffer, capacity, 0);
|
|
if (query_id[isock] < 0)
|
|
printf("Failed to send mDNS query: %s\n", strerror(errno));
|
|
}
|
|
|
|
// This is a simple implementation that loops for 5 seconds or as long as we get replies
|
|
int res;
|
|
printf("Reading mDNS query replies\n");
|
|
int records = 0;
|
|
do {
|
|
struct timeval timeout;
|
|
timeout.tv_sec = 10;
|
|
timeout.tv_usec = 0;
|
|
|
|
int nfds = 0;
|
|
fd_set readfs;
|
|
FD_ZERO(&readfs);
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (sockets[isock] >= nfds)
|
|
nfds = sockets[isock] + 1;
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
|
|
res = select(nfds, &readfs, 0, 0, &timeout);
|
|
if (res > 0) {
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (FD_ISSET(sockets[isock], &readfs)) {
|
|
size_t rec = mdns_query_recv(sockets[isock], buffer, capacity, query_callback,
|
|
user_data, query_id[isock]);
|
|
if (rec > 0)
|
|
records += rec;
|
|
}
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
}
|
|
} while (res > 0);
|
|
|
|
printf("Read %d records\n", records);
|
|
|
|
free(buffer);
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_socket_close(sockets[isock]);
|
|
printf("Closed socket%s\n", num_sockets ? "s" : "");
|
|
|
|
return 0;
|
|
}
|
|
|
|
// Provide a mDNS service, answering incoming DNS-SD and mDNS queries
|
|
int
|
|
service_mdns(const char* hostname, const char* service_name, int service_port) {
|
|
int sockets[32];
|
|
int num_sockets = open_service_sockets(sockets, sizeof(sockets) / sizeof(sockets[0]));
|
|
if (num_sockets <= 0) {
|
|
printf("Failed to open any client sockets\n");
|
|
return -1;
|
|
}
|
|
printf("Opened %d socket%s for mDNS service\n", num_sockets, num_sockets ? "s" : "");
|
|
|
|
size_t service_name_length = strlen(service_name);
|
|
if (!service_name_length) {
|
|
printf("Invalid service name\n");
|
|
return -1;
|
|
}
|
|
|
|
char* service_name_buffer = malloc(service_name_length + 2);
|
|
memcpy(service_name_buffer, service_name, service_name_length);
|
|
if (service_name_buffer[service_name_length - 1] != '.')
|
|
service_name_buffer[service_name_length++] = '.';
|
|
service_name_buffer[service_name_length] = 0;
|
|
service_name = service_name_buffer;
|
|
|
|
printf("Service mDNS: %s:%d\n", service_name, service_port);
|
|
printf("Hostname: %s\n", hostname);
|
|
|
|
size_t capacity = 2048;
|
|
void* buffer = malloc(capacity);
|
|
|
|
mdns_string_t service_string = (mdns_string_t){service_name, strlen(service_name)};
|
|
mdns_string_t hostname_string = (mdns_string_t){hostname, strlen(hostname)};
|
|
|
|
// Build the service instance "<hostname>.<_service-name>._tcp.local." string
|
|
char service_instance_buffer[256] = {0};
|
|
snprintf(service_instance_buffer, sizeof(service_instance_buffer) - 1, "%.*s.%.*s",
|
|
MDNS_STRING_FORMAT(hostname_string), MDNS_STRING_FORMAT(service_string));
|
|
mdns_string_t service_instance_string =
|
|
(mdns_string_t){service_instance_buffer, strlen(service_instance_buffer)};
|
|
|
|
// Build the "<hostname>.local." string
|
|
char qualified_hostname_buffer[256] = {0};
|
|
snprintf(qualified_hostname_buffer, sizeof(qualified_hostname_buffer) - 1, "%.*s.local.",
|
|
MDNS_STRING_FORMAT(hostname_string));
|
|
mdns_string_t hostname_qualified_string =
|
|
(mdns_string_t){qualified_hostname_buffer, strlen(qualified_hostname_buffer)};
|
|
|
|
service_t service = {0};
|
|
service.service = service_string;
|
|
service.hostname = hostname_string;
|
|
service.service_instance = service_instance_string;
|
|
service.hostname_qualified = hostname_qualified_string;
|
|
service.address_ipv4 = service_address_ipv4;
|
|
service.address_ipv6 = service_address_ipv6;
|
|
service.port = service_port;
|
|
|
|
// Setup our mDNS records
|
|
|
|
// PTR record reverse mapping "<_service-name>._tcp.local." to
|
|
// "<hostname>.<_service-name>._tcp.local."
|
|
service.record_ptr = (mdns_record_t){.name = service.service,
|
|
.type = MDNS_RECORDTYPE_PTR,
|
|
.data.ptr.name = service.service_instance,
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
|
|
// SRV record mapping "<hostname>.<_service-name>._tcp.local." to
|
|
// "<hostname>.local." with port. Set weight & priority to 0.
|
|
service.record_srv = (mdns_record_t){.name = service.service_instance,
|
|
.type = MDNS_RECORDTYPE_SRV,
|
|
.data.srv.name = service.hostname_qualified,
|
|
.data.srv.port = service.port,
|
|
.data.srv.priority = 0,
|
|
.data.srv.weight = 0,
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
|
|
// A/AAAA records mapping "<hostname>.local." to IPv4/IPv6 addresses
|
|
service.record_a = (mdns_record_t){.name = service.hostname_qualified,
|
|
.type = MDNS_RECORDTYPE_A,
|
|
.data.a.addr = service.address_ipv4,
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
|
|
service.record_aaaa = (mdns_record_t){.name = service.hostname_qualified,
|
|
.type = MDNS_RECORDTYPE_AAAA,
|
|
.data.aaaa.addr = service.address_ipv6,
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
|
|
// Add two test TXT records for our service instance name, will be coalesced into
|
|
// one record with both key-value pair strings by the library
|
|
service.txt_record[0] = (mdns_record_t){.name = service.service_instance,
|
|
.type = MDNS_RECORDTYPE_TXT,
|
|
.data.txt.key = {MDNS_STRING_CONST("test")},
|
|
.data.txt.value = {MDNS_STRING_CONST("1")},
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
service.txt_record[1] = (mdns_record_t){.name = service.service_instance,
|
|
.type = MDNS_RECORDTYPE_TXT,
|
|
.data.txt.key = {MDNS_STRING_CONST("other")},
|
|
.data.txt.value = {MDNS_STRING_CONST("value")},
|
|
.rclass = 0,
|
|
.ttl = 0};
|
|
|
|
// Send an announcement on startup of service
|
|
{
|
|
printf("Sending announce\n");
|
|
mdns_record_t additional[5] = {0};
|
|
size_t additional_count = 0;
|
|
additional[additional_count++] = service.record_srv;
|
|
if (service.address_ipv4.sin_family == AF_INET)
|
|
additional[additional_count++] = service.record_a;
|
|
if (service.address_ipv6.sin6_family == AF_INET6)
|
|
additional[additional_count++] = service.record_aaaa;
|
|
additional[additional_count++] = service.txt_record[0];
|
|
additional[additional_count++] = service.txt_record[1];
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_announce_multicast(sockets[isock], buffer, capacity, service.record_ptr, 0, 0,
|
|
additional, additional_count);
|
|
}
|
|
|
|
// This is a crude implementation that checks for incoming queries
|
|
while (running) {
|
|
int nfds = 0;
|
|
fd_set readfs;
|
|
FD_ZERO(&readfs);
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (sockets[isock] >= nfds)
|
|
nfds = sockets[isock] + 1;
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
|
|
struct timeval timeout;
|
|
timeout.tv_sec = 0;
|
|
timeout.tv_usec = 100000;
|
|
|
|
if (select(nfds, &readfs, 0, 0, &timeout) >= 0) {
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (FD_ISSET(sockets[isock], &readfs)) {
|
|
mdns_socket_listen(sockets[isock], buffer, capacity, service_callback,
|
|
&service);
|
|
}
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Send a goodbye on end of service
|
|
{
|
|
printf("Sending goodbye\n");
|
|
mdns_record_t additional[5] = {0};
|
|
size_t additional_count = 0;
|
|
additional[additional_count++] = service.record_srv;
|
|
if (service.address_ipv4.sin_family == AF_INET)
|
|
additional[additional_count++] = service.record_a;
|
|
if (service.address_ipv6.sin6_family == AF_INET6)
|
|
additional[additional_count++] = service.record_aaaa;
|
|
additional[additional_count++] = service.txt_record[0];
|
|
additional[additional_count++] = service.txt_record[1];
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_goodbye_multicast(sockets[isock], buffer, capacity, service.record_ptr, 0, 0,
|
|
additional, additional_count);
|
|
}
|
|
|
|
free(buffer);
|
|
free(service_name_buffer);
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_socket_close(sockets[isock]);
|
|
printf("Closed socket%s\n", num_sockets ? "s" : "");
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
// Dump all incoming mDNS queries and answers
|
|
static int
|
|
dump_mdns(void) {
|
|
int sockets[32];
|
|
int num_sockets = open_service_sockets(sockets, sizeof(sockets) / sizeof(sockets[0]));
|
|
if (num_sockets <= 0) {
|
|
printf("Failed to open any client sockets\n");
|
|
return -1;
|
|
}
|
|
printf("Opened %d socket%s for mDNS dump\n", num_sockets, num_sockets ? "s" : "");
|
|
|
|
size_t capacity = 2048;
|
|
void* buffer = malloc(capacity);
|
|
|
|
// This is a crude implementation that checks for incoming queries and answers
|
|
while (running) {
|
|
int nfds = 0;
|
|
fd_set readfs;
|
|
FD_ZERO(&readfs);
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (sockets[isock] >= nfds)
|
|
nfds = sockets[isock] + 1;
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
|
|
struct timeval timeout;
|
|
timeout.tv_sec = 0;
|
|
timeout.tv_usec = 100000;
|
|
|
|
if (select(nfds, &readfs, 0, 0, &timeout) >= 0) {
|
|
for (int isock = 0; isock < num_sockets; ++isock) {
|
|
if (FD_ISSET(sockets[isock], &readfs)) {
|
|
mdns_socket_listen(sockets[isock], buffer, capacity, dump_callback, 0);
|
|
}
|
|
FD_SET(sockets[isock], &readfs);
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
free(buffer);
|
|
|
|
for (int isock = 0; isock < num_sockets; ++isock)
|
|
mdns_socket_close(sockets[isock]);
|
|
printf("Closed socket%s\n", num_sockets ? "s" : "");
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef MDNS_FUZZING
|
|
|
|
#undef printf
|
|
|
|
// Fuzzing by piping random data into the recieve functions
|
|
static void
|
|
fuzz_mdns(void) {
|
|
#define MAX_FUZZ_SIZE 4096
|
|
#define MAX_PASSES (1024 * 1024 * 1024)
|
|
|
|
static uint8_t fuzz_mdns_services_query[] = {
|
|
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x09, '_',
|
|
's', 'e', 'r', 'v', 'i', 'c', 'e', 's', 0x07, '_', 'd', 'n', 's', '-',
|
|
's', 'd', 0x04, '_', 'u', 'd', 'p', 0x05, 'l', 'o', 'c', 'a', 'l', 0x00};
|
|
|
|
uint8_t* buffer = malloc(MAX_FUZZ_SIZE);
|
|
uint8_t* strbuffer = malloc(MAX_FUZZ_SIZE);
|
|
for (int ipass = 0; ipass < MAX_PASSES; ++ipass) {
|
|
size_t size = rand() % MAX_FUZZ_SIZE;
|
|
for (size_t i = 0; i < size; ++i)
|
|
buffer[i] = rand() & 0xFF;
|
|
|
|
if (ipass % 4) {
|
|
// Crafted fuzzing, make sure header is reasonable
|
|
memcpy(buffer, fuzz_mdns_services_query, sizeof(fuzz_mdns_services_query));
|
|
uint16_t* header = (uint16_t*)buffer;
|
|
header[0] = 0;
|
|
header[1] = htons(0x8400);
|
|
for (int ival = 2; ival < 6; ++ival)
|
|
header[ival] = rand() & 0xFF;
|
|
}
|
|
mdns_discovery_recv(0, (void*)buffer, size, query_callback, 0);
|
|
|
|
mdns_socket_listen(0, (void*)buffer, size, service_callback, 0);
|
|
|
|
if (ipass % 4) {
|
|
// Crafted fuzzing, make sure header is reasonable (1 question claimed).
|
|
// Earlier passes will have done completely random data
|
|
uint16_t* header = (uint16_t*)buffer;
|
|
header[2] = htons(1);
|
|
}
|
|
mdns_query_recv(0, (void*)buffer, size, query_callback, 0, 0);
|
|
|
|
// Fuzzing by piping random data into the parse functions
|
|
size_t offset = size ? (rand() % size) : 0;
|
|
size_t length = size ? (rand() % (size - offset)) : 0;
|
|
mdns_record_parse_ptr(buffer, size, offset, length, strbuffer, MAX_FUZZ_SIZE);
|
|
|
|
offset = size ? (rand() % size) : 0;
|
|
length = size ? (rand() % (size - offset)) : 0;
|
|
mdns_record_parse_srv(buffer, size, offset, length, strbuffer, MAX_FUZZ_SIZE);
|
|
|
|
struct sockaddr_in addr_ipv4;
|
|
offset = size ? (rand() % size) : 0;
|
|
length = size ? (rand() % (size - offset)) : 0;
|
|
mdns_record_parse_a(buffer, size, offset, length, &addr_ipv4);
|
|
|
|
struct sockaddr_in6 addr_ipv6;
|
|
offset = size ? (rand() % size) : 0;
|
|
length = size ? (rand() % (size - offset)) : 0;
|
|
mdns_record_parse_aaaa(buffer, size, offset, length, &addr_ipv6);
|
|
|
|
offset = size ? (rand() % size) : 0;
|
|
length = size ? (rand() % (size - offset)) : 0;
|
|
mdns_record_parse_txt(buffer, size, offset, length, (mdns_record_txt_t*)strbuffer,
|
|
MAX_FUZZ_SIZE);
|
|
|
|
if (ipass && !(ipass % 10000))
|
|
printf("Completed fuzzing pass %d\n", ipass);
|
|
}
|
|
|
|
free(buffer);
|
|
free(strbuffer);
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifdef _WIN32
|
|
BOOL console_handler(DWORD signal) {
|
|
if (signal == CTRL_C_EVENT) {
|
|
running = 0;
|
|
}
|
|
return TRUE;
|
|
}
|
|
#else
|
|
void signal_handler(int signal) {
|
|
running = 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
int
|
|
main(int argc, const char* const* argv) {
|
|
int mode = 0;
|
|
const char* service = "_test-mdns._tcp.local.";
|
|
const char* hostname = "dummy-host";
|
|
mdns_query_t query[16];
|
|
size_t query_count = 0;
|
|
int service_port = 42424;
|
|
server_info_t server_info;
|
|
memset(&server_info, 0, sizeof(server_info_t));
|
|
|
|
#ifdef _WIN32
|
|
|
|
WORD versionWanted = MAKEWORD(1, 1);
|
|
WSADATA wsaData;
|
|
if (WSAStartup(versionWanted, &wsaData)) {
|
|
printf("Failed to initialize WinSock\n");
|
|
return -1;
|
|
}
|
|
|
|
char hostname_buffer[256];
|
|
DWORD hostname_size = (DWORD)sizeof(hostname_buffer);
|
|
if (GetComputerNameA(hostname_buffer, &hostname_size))
|
|
hostname = hostname_buffer;
|
|
|
|
SetConsoleCtrlHandler(console_handler, TRUE);
|
|
#else
|
|
|
|
char hostname_buffer[256];
|
|
size_t hostname_size = sizeof(hostname_buffer);
|
|
if (gethostname(hostname_buffer, hostname_size) == 0)
|
|
hostname = hostname_buffer;
|
|
signal(SIGINT, signal_handler);
|
|
#endif
|
|
|
|
for (int iarg = 0; iarg < argc; ++iarg) {
|
|
if (strcmp(argv[iarg], "--discovery") == 0) {
|
|
mode = 0;
|
|
} else if (strcmp(argv[iarg], "--query") == 0) {
|
|
// Each query is either a service name, or a pair of record type and a service name
|
|
// For example:
|
|
// mdns --query _foo._tcp.local.
|
|
// mdns --query SRV myhost._foo._tcp.local.
|
|
// mdns --query A myhost._tcp.local. _service._tcp.local.
|
|
mode = 1;
|
|
++iarg;
|
|
while ((iarg < argc) && (query_count < 16)) {
|
|
query[query_count].name = argv[iarg++];
|
|
query[query_count].type = MDNS_RECORDTYPE_PTR;
|
|
if (iarg < argc) {
|
|
mdns_record_type_t record_type = 0;
|
|
if (strcmp(query[query_count].name, "PTR") == 0)
|
|
record_type = MDNS_RECORDTYPE_PTR;
|
|
else if (strcmp(query[query_count].name, "SRV") == 0)
|
|
record_type = MDNS_RECORDTYPE_SRV;
|
|
else if (strcmp(query[query_count].name, "A") == 0)
|
|
record_type = MDNS_RECORDTYPE_A;
|
|
else if (strcmp(query[query_count].name, "AAAA") == 0)
|
|
record_type = MDNS_RECORDTYPE_AAAA;
|
|
if (record_type != 0) {
|
|
query[query_count].type = record_type;
|
|
query[query_count].name = argv[iarg++];
|
|
}
|
|
}
|
|
query[query_count].length = strlen(query[query_count].name);
|
|
++query_count;
|
|
}
|
|
} else if (strcmp(argv[iarg], "--service") == 0) {
|
|
mode = 2;
|
|
++iarg;
|
|
if (iarg < argc)
|
|
service = argv[iarg];
|
|
} else if (strcmp(argv[iarg], "--dump") == 0) {
|
|
mode = 3;
|
|
} else if (strcmp(argv[iarg], "--hostname") == 0) {
|
|
++iarg;
|
|
if (iarg < argc)
|
|
hostname = argv[iarg];
|
|
} else if (strcmp(argv[iarg], "--port") == 0) {
|
|
++iarg;
|
|
if (iarg < argc)
|
|
service_port = atoi(argv[iarg]);
|
|
}
|
|
}
|
|
|
|
#ifdef MDNS_FUZZING
|
|
fuzz_mdns();
|
|
#else
|
|
int ret;
|
|
if (mode == 0)
|
|
ret = send_dns_sd();
|
|
else if (mode == 1)
|
|
ret = send_mdns_query(query, query_count, &server_info);
|
|
else if (mode == 2)
|
|
ret = service_mdns(hostname, service, service_port);
|
|
else if (mode == 3)
|
|
ret = dump_mdns();
|
|
#endif
|
|
|
|
#ifdef _WIN32
|
|
WSACleanup();
|
|
#endif
|
|
|
|
printf("ip %s, port %d, domain %s\n", server_info.ip, server_info.port, server_info.domain);
|
|
return 0;
|
|
}
|
|
*/
|