mDNSShared/PlatformCommon.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   4  *
   5  * @APPLE_LICENSE_HEADER_START@
   6  *
   7  * This file contains Original Code and/or Modifications of Original Code
   8  * as defined in and that are subject to the Apple Public Source License
   9  * Version 2.0 (the 'License'). You may not use this file except in
  10  * compliance with the License. Please obtain a copy of the License at
  11  * http://www.opensource.apple.com/apsl/ and read it before using this
  12  * file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  19  * Please see the License for the specific language governing rights and
  20  * limitations under the License.
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  22  * @APPLE_LICENSE_HEADER_END@
  23
  24     Change History (most recent first):
  25
  26 $Log: PlatformCommon.c,v $
  27 Revision 1.6  2005/04/08 21:30:16  ksekar
  28 <rdar://problem/4007457> Compiling problems with mDNSResponder-98 on Solaris/Sparc v9
  29 Patch submitted by Bernd Kuhls
  30
  31 Revision 1.5  2005/02/01 19:33:30  ksekar
  32 <rdar://problem/3985239> Keychain format too restrictive
  33
  34 Revision 1.4  2005/01/19 19:19:21  ksekar
  35 <rdar://problem/3960191> Need a way to turn off domain discovery
  36
  37 Revision 1.3  2004/12/13 17:46:52  cheshire
  38 Use sizeof(buf) instead of fixed constant 1024
  39
  40 Revision 1.2  2004/12/01 03:30:29  cheshire
  41 <rdar://problem/3889346> Add Unicast DNS support to mDNSPosix
  42
  43 Revision 1.1  2004/12/01 01:51:35  cheshire
  44 Move ReadDDNSSettingsFromConfFile() from mDNSMacOSX.c to PlatformCommon.c
  45
  46  */
  47
  48 #include <stdio.h>                              // Needed for fopen() etc.
  49 #include <unistd.h>                             // Needed for close()
  50 #include <string.h>                             // Needed for strlen() etc.
  51 #include <errno.h>                      // Needed for errno etc.
  52 #include <sys/socket.h>                 // Needed for socket() etc.
  53 #include <netinet/in.h>                 // Needed for sockaddr_in
  54
  55 #include "mDNSEmbeddedAPI.h"    // Defines the interface provided to the client layer above
  56 #include "PlatformCommon.h"
  57
  58 #ifdef NOT_HAVE_SOCKLEN_T
  59     typedef unsigned int socklen_t;
  60 #endif
  61
  62 // Bind a UDP socket to a global destination to find the default route's interface address
  63 mDNSexport void FindDefaultRouteIP(mDNSAddr *a)
  64         {
  65         struct sockaddr_in addr;
  66         socklen_t len = sizeof(addr);
  67         int sock = socket(AF_INET,SOCK_DGRAM,0);
  68         a->type = mDNSAddrType_None;
  69         if (sock == -1) return;
  70         addr.sin_family = AF_INET;
  71         addr.sin_port = 1;      // Not important, any port and public address will do
  72         addr.sin_addr.s_addr = 0x11111111;
  73         if ((connect(sock,(const struct sockaddr*)&addr,sizeof(addr))) == -1) { close(sock); return; }
  74         if ((getsockname(sock,(struct sockaddr*)&addr, &len)) == -1) { close(sock); return; }
  75         close(sock);
  76         a->type = mDNSAddrType_IPv4;
  77         a->ip.v4.NotAnInteger = addr.sin_addr.s_addr;
  78         }
  79
  80 // dst must be at least MAX_ESCAPED_DOMAIN_NAME bytes, and option must be less than 32 bytes in length
  81 mDNSlocal mDNSBool GetConfigOption(char *dst, const char *option, FILE *f)
  82         {
  83         char buf[32+1+MAX_ESCAPED_DOMAIN_NAME]; // Option name, one space, option value
  84         unsigned int len = strlen(option);
  85         if (len + 1 + MAX_ESCAPED_DOMAIN_NAME > sizeof(buf)-1) { LogMsg("GetConfigOption: option %s too long", option); return mDNSfalse; }
  86         fseek(f, 0, SEEK_SET);  // set position to beginning of stream
  87         while (fgets(buf, sizeof(buf), f))              // Read at most sizeof(buf)-1 bytes from file, and append '\0' C-string terminator
  88                 {
  89                 if (!strncmp(buf, option, len))
  90                         {
  91                         strncpy(dst, buf + len + 1, MAX_ESCAPED_DOMAIN_NAME-1);
  92                         if (dst[MAX_ESCAPED_DOMAIN_NAME-1]) dst[MAX_ESCAPED_DOMAIN_NAME-1] = '\0';
  93                         len = strlen(dst);
  94                         if (len && dst[len-1] == '\n') dst[len-1] = '\0';  // chop newline
  95                         return mDNStrue;
  96                         }
  97                 }
  98         debugf("Option %s not set", option);
  99         return mDNSfalse;
 100         }
 101
 102 mDNSexport void ReadDDNSSettingsFromConfFile(mDNS *const m, const char *const filename, domainname *const hostname, domainname *const domain, mDNSBool *DomainDiscoveryDisabled)
 103         {
 104         char buf   [MAX_ESCAPED_DOMAIN_NAME];
 105         char secret[MAX_ESCAPED_DOMAIN_NAME] = "";
 106         mStatus err;
 107         FILE *f = fopen(filename, "r");
 108
 109     if (hostname)                 hostname->c[0] = 0;
 110     if (domain)                   domain->c[0] = 0;
 111         if (DomainDiscoveryDisabled) *DomainDiscoveryDisabled = mDNSfalse;
 112
 113         if (f)
 114                 {
 115                 if (DomainDiscoveryDisabled && GetConfigOption(buf, "DomainDiscoveryDisabled", f) && !strcasecmp(buf, "true")) *DomainDiscoveryDisabled = mDNStrue;
 116                 if (hostname && GetConfigOption(buf, "hostname", f) && !MakeDomainNameFromDNSNameString(hostname, buf)) goto badf;
 117                 if (domain && GetConfigOption(buf, "zone", f) && !MakeDomainNameFromDNSNameString(domain, buf)) goto badf;
 118                 GetConfigOption(secret, "secret-64", f);  // failure means no authentication
 119                 fclose(f);
 120                 f = NULL;
 121                 }
 122         else
 123                 {
 124                 if (errno != ENOENT) LogMsg("ERROR: Config file exists, but cannot be opened.");
 125                 return;
 126                 }
 127
 128         if (domain && domain->c[0] && secret[0])
 129                 {
 130                 // for now we assume keyname = service reg domain and we use same key for service and hostname registration
 131                 err = mDNS_SetSecretForZone(m, domain, domain, secret);
 132                 if (err) LogMsg("ERROR: mDNS_SetSecretForZone returned %d for domain %##s", err, domain->c);
 133                 }
 134
 135         return;
 136
 137         badf:
 138         LogMsg("ERROR: malformatted config file");
 139         if (f) fclose(f);
 140         }