mDNSMacOS9/Responder.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <stdio.h>                      // For printf()
  19 #include <string.h>                     // For strcpy()
  20
  21 #include <Events.h>                     // For WaitNextEvent()
  22
  23 #include <OpenTransport.h>
  24 #include <OpenTptInternet.h>
  25
  26 #include <SIOUX.h>                      // For SIOUXHandleOneEvent()
  27
  28 #include "dns_sd.h"
  29
  30 typedef union { UInt8 b[2]; UInt16 NotAnInteger; } mDNSOpaque16;
  31 static UInt16 mDNSVal16(mDNSOpaque16 x) { return((UInt16)(x.b[0]<<8 | x.b[1])); }
  32 static mDNSOpaque16 mDNSOpaque16fromIntVal(UInt16 v)
  33 { mDNSOpaque16 x; x.b[0] = (UInt8)(v >> 8); x.b[1] = (UInt8)(v & 0xFF); return(x); }
  34
  35 typedef struct RegisteredService_struct RegisteredService;
  36 struct RegisteredService_struct
  37 {
  38     RegisteredService *next;
  39     DNSServiceRef sdRef;
  40     Boolean gotresult;
  41     DNSServiceErrorType errorCode;
  42     char namestr[64];
  43     char typestr[kDNSServiceMaxDomainName];
  44     char domstr [kDNSServiceMaxDomainName];
  45 };
  46
  47 static RegisteredService p1, p2, afp, http, njp;
  48 static RegisteredService *services = NULL, **nextservice = &services;
  49
  50 static void RegCallback(DNSServiceRef sdRef, DNSServiceFlags flags, DNSServiceErrorType errorCode,
  51                         const char *name, const char *regtype, const char *domain, void *context)
  52 {
  53     RegisteredService *rs = (RegisteredService *)context;
  54     (void)sdRef;    // Unused
  55     (void)flags;    // Unused
  56     rs->gotresult = true;
  57     rs->errorCode = errorCode;
  58     strcpy(rs->namestr, name);
  59     strcpy(rs->typestr, regtype);
  60     strcpy(rs->domstr,  domain);
  61 }
  62
  63 static DNSServiceErrorType RegisterService(RegisteredService *rs, mDNSOpaque16 OpaquePort,
  64                                            const char name[], const char type[], const char domain[], const char txtinfo[])
  65 {
  66     DNSServiceErrorType err;
  67     unsigned char txtbuffer[257];
  68     strncpy((char*)txtbuffer+1, txtinfo, 255);
  69     txtbuffer[256] = 0;
  70     txtbuffer[0] = (unsigned char)strlen((char*)txtbuffer);
  71     rs->gotresult = 0;
  72     rs->errorCode = kDNSServiceErr_NoError;
  73     err = DNSServiceRegister(&rs->sdRef, /* kDNSServiceFlagsAutoRename*/ 0, 0,
  74                              name, type, domain, NULL, OpaquePort.NotAnInteger, (unsigned short)(1+txtbuffer[0]), txtbuffer, RegCallback, rs);
  75     if (err)
  76         printf("RegisterService(%s %s %s) failed %d\n", name, type, domain, err);
  77     else
  78     { *nextservice = rs; nextservice = &rs->next; }
  79     return(err);
  80 }
  81
  82 // RegisterFakeServiceForTesting() simulates the effect of services being registered on
  83 // dynamically-allocated port numbers. No real service exists on that port -- this is just for testing.
  84 static DNSServiceErrorType RegisterFakeServiceForTesting(RegisteredService *rs,
  85                                                          const char name[], const char type[], const char domain[], const char txtinfo[])
  86 {
  87     static UInt16 NextPort = 0xF000;
  88     return RegisterService(rs, mDNSOpaque16fromIntVal(NextPort++), name, type, domain, txtinfo);
  89 }
  90
  91 // CreateProxyRegistrationForRealService() checks to see if the given port is currently
  92 // in use, and if so, advertises the specified service as present on that port.
  93 // This is useful for advertising existing real services (Personal Web Sharing, Personal
  94 // File Sharing, etc.) that currently don't register with mDNS Service Discovery themselves.
  95 static DNSServiceErrorType CreateProxyRegistrationForRealService(RegisteredService *rs,
  96                                                                  const char *servicetype, UInt16 PortAsNumber, const char txtinfo[])
  97 {
  98     mDNSOpaque16 OpaquePort = mDNSOpaque16fromIntVal(PortAsNumber);
  99     InetAddress ia;
 100     TBind bindReq;
 101     OSStatus err;
 102     TEndpointInfo endpointinfo;
 103     EndpointRef ep = OTOpenEndpoint(OTCreateConfiguration(kTCPName), 0, &endpointinfo, &err);
 104     if (!ep || err) { printf("OTOpenEndpoint (CreateProxyRegistrationForRealService) failed %d", err); return(err); }
 105
 106     ia.fAddressType = AF_INET;
 107     ia.fPort        = OpaquePort.NotAnInteger;
 108     ia.fHost        = 0;
 109     bindReq.addr.maxlen = sizeof(ia);
 110     bindReq.addr.len    = sizeof(ia);
 111     bindReq.addr.buf    = (UInt8*)&ia;
 112     bindReq.qlen        = 0;
 113     err = OTBind(ep, &bindReq, NULL);
 114
 115     if (err == kOTBadAddressErr)
 116         err = RegisterService(rs, OpaquePort, "", servicetype, "local.", txtinfo);
 117     else if (err)
 118         printf("OTBind failed %d", err);
 119
 120     OTCloseProvider(ep);
 121     return(err);
 122 }
 123
 124 // YieldSomeTime() just cooperatively yields some time to other processes running on classic Mac OS
 125 static Boolean YieldSomeTime(UInt32 milliseconds)
 126 {
 127     extern Boolean SIOUXQuitting;
 128     EventRecord e;
 129     WaitNextEvent(everyEvent, &e, milliseconds / 17, NULL);
 130     SIOUXHandleOneEvent(&e);
 131     return(SIOUXQuitting);
 132 }
 133
 134 int main()
 135 {
 136     OSStatus err;
 137     RegisteredService *s;
 138
 139     SIOUXSettings.asktosaveonclose = false;
 140     SIOUXSettings.userwindowtitle = "\pMulticast DNS Responder";
 141
 142     printf("Multicast DNS Responder\n\n");
 143     printf("This software reports errors using MacsBug breaks,\n");
 144     printf("so if you don't have MacsBug installed your Mac may crash.\n\n");
 145     printf("******************************************************************************\n\n");
 146
 147     err = InitOpenTransport();
 148     if (err) { printf("InitOpenTransport failed %d", err); return(err); }
 149
 150     printf("Advertising Services...\n");
 151
 152 #define SRSET 0
 153 #if SRSET==0
 154     RegisterFakeServiceForTesting(&p1, "Web Server One", "_http._tcp.", "local.", "path=/index.html");
 155     RegisterFakeServiceForTesting(&p2, "Web Server Two", "_http._tcp.", "local.", "path=/path.html");
 156 #elif SRSET==1
 157     RegisterFakeServiceForTesting(&p1, "Epson Stylus 900N", "_printer._tcp.", "local.", "rn=lpq1");
 158     RegisterFakeServiceForTesting(&p2, "HP LaserJet",       "_printer._tcp.", "local.", "rn=lpq2");
 159 #else
 160     RegisterFakeServiceForTesting(&p1, "My Printer",        "_printer._tcp.", "local.", "rn=lpq3");
 161     RegisterFakeServiceForTesting(&p2, "My Other Printer",  "_printer._tcp.", "local.", "lrn=pq4");
 162 #endif
 163
 164     // If AFP Server is running, register a record for it
 165     CreateProxyRegistrationForRealService(&afp, "_afpovertcp._tcp.", 548, "");
 166
 167     // If Web Server is running, register a record for it
 168     CreateProxyRegistrationForRealService(&http, "_http._tcp.",       80, "path=/index.html");
 169
 170     while (!YieldSomeTime(35))
 171         for (s = services; s; s = s->next)
 172             if (s->gotresult)
 173             {
 174                 printf("%s %s %s registered\n", s->namestr, s->typestr, s->domstr);
 175                 s->gotresult = false;
 176             }
 177
 178     for (s = services; s; s = s->next)
 179         if (s->sdRef) DNSServiceRefDeallocate(s->sdRef);
 180
 181     CloseOpenTransport();
 182     return(0);
 183 }