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> // Needed for fopen() etc. 19 #include <unistd.h> // Needed for close() 20 #include <string.h> // Needed for strlen() etc. 21 #include <errno.h> // Needed for errno etc. 22 #include <sys/socket.h> // Needed for socket() etc. 23 #include <netinet/in.h> // Needed for sockaddr_in 24 #include <syslog.h> 25 26 #include "mDNSEmbeddedAPI.h" // Defines the interface provided to the client layer above 27 #include "DNSCommon.h" 28 #include "PlatformCommon.h" 29 30 #ifdef NOT_HAVE_SOCKLEN_T 31 typedef unsigned int socklen_t; 32 #endif 33 34 // Bind a UDP socket to find the source address to a destination 35 mDNSexport void mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst) 36 { 37 union { struct sockaddr s; struct sockaddr_in a4; struct sockaddr_in6 a6; } addr; 38 socklen_t len = sizeof(addr); 39 socklen_t inner_len = 0; 40 int sock = socket(AF_INET, SOCK_DGRAM, 0); 41 src->type = mDNSAddrType_None; 42 if (sock == -1) return; 43 if (dst->type == mDNSAddrType_IPv4) 44 { 45 inner_len = sizeof(addr.a4); 46 #ifndef NOT_HAVE_SA_LEN 47 addr.a4.sin_len = inner_len; 48 #endif 49 addr.a4.sin_family = AF_INET; 50 addr.a4.sin_port = 1; // Not important, any port will do 51 addr.a4.sin_addr.s_addr = dst->ip.v4.NotAnInteger; 52 } 53 else if (dst->type == mDNSAddrType_IPv6) 54 { 55 inner_len = sizeof(addr.a6); 56 #ifndef NOT_HAVE_SA_LEN 57 addr.a6.sin6_len = inner_len; 58 #endif 59 addr.a6.sin6_family = AF_INET6; 60 addr.a6.sin6_flowinfo = 0; 61 addr.a6.sin6_port = 1; // Not important, any port will do 62 addr.a6.sin6_addr = *(struct in6_addr*)&dst->ip.v6; 63 addr.a6.sin6_scope_id = 0; 64 } 65 else return; 66 67 if ((connect(sock, &addr.s, inner_len)) < 0) 68 { if (errno != ENETUNREACH) LogMsg("mDNSPlatformSourceAddrForDest: connect %#a failed errno %d (%s)", dst, errno, strerror(errno)); goto exit; } 69 70 if ((getsockname(sock, &addr.s, &len)) < 0) 71 { LogMsg("mDNSPlatformSourceAddrForDest: getsockname failed errno %d (%s)", errno, strerror(errno)); goto exit; } 72 73 src->type = dst->type; 74 if (dst->type == mDNSAddrType_IPv4) src->ip.v4.NotAnInteger = addr.a4.sin_addr.s_addr; 75 else src->ip.v6 = *(mDNSv6Addr*)&addr.a6.sin6_addr; 76 exit: 77 close(sock); 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 mStatus err; 106 FILE *f = fopen(filename, "r"); 107 108 if (hostname) hostname->c[0] = 0; 109 if (domain) domain->c[0] = 0; 110 if (DomainDiscoveryDisabled) *DomainDiscoveryDisabled = mDNSfalse; 111 112 if (f) 113 { 114 if (DomainDiscoveryDisabled && GetConfigOption(buf, "DomainDiscoveryDisabled", f) && !strcasecmp(buf, "true")) *DomainDiscoveryDisabled = mDNStrue; 115 if (hostname && GetConfigOption(buf, "hostname", f) && !MakeDomainNameFromDNSNameString(hostname, buf)) goto badf; 116 if (domain && GetConfigOption(buf, "zone", f) && !MakeDomainNameFromDNSNameString(domain, buf)) goto badf; 117 buf[0] = 0; 118 GetConfigOption(buf, "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] && buf[0]) 129 { 130 DomainAuthInfo *info = (DomainAuthInfo*)mDNSPlatformMemAllocate(sizeof(*info)); 131 // for now we assume keyname = service reg domain and we use same key for service and hostname registration 132 err = mDNS_SetSecretForDomain(m, info, domain, domain, buf, NULL, 0, mDNSfalse); 133 if (err) LogMsg("ERROR: mDNS_SetSecretForDomain returned %d for domain %##s", err, domain->c); 134 } 135 136 return; 137 138 badf: 139 LogMsg("ERROR: malformatted config file"); 140 if (f) fclose(f); 141 } 142 143 #if MDNS_DEBUGMSGS 144 mDNSexport void mDNSPlatformWriteDebugMsg(const char *msg) 145 { 146 fprintf(stderr,"%s\n", msg); 147 fflush(stderr); 148 } 149 #endif 150 151 mDNSexport void mDNSPlatformWriteLogMsg(const char *ident, const char *buffer, mDNSLogLevel_t loglevel) 152 { 153 #if APPLE_OSX_mDNSResponder && LogTimeStamps 154 extern mDNS mDNSStorage; 155 extern mDNSu32 mDNSPlatformClockDivisor; 156 mDNSs32 t = mDNSStorage.timenow ? mDNSStorage.timenow : mDNSPlatformClockDivisor ? mDNS_TimeNow_NoLock(&mDNSStorage) : 0; 157 int ms = ((t < 0) ? -t : t) % 1000; 158 #endif 159 160 if (mDNS_DebugMode) // In debug mode we write to stderr 161 { 162 #if APPLE_OSX_mDNSResponder && LogTimeStamps 163 if (ident && ident[0] && mDNSPlatformClockDivisor) 164 fprintf(stderr,"%8d.%03d: %s\n", (int)(t/1000), ms, buffer); 165 else 166 #endif 167 fprintf(stderr,"%s\n", buffer); 168 fflush(stderr); 169 } 170 else // else, in production mode, we write to syslog 171 { 172 static int log_inited = 0; 173 174 int syslog_level = LOG_ERR; 175 switch (loglevel) 176 { 177 case MDNS_LOG_MSG: syslog_level = LOG_ERR; break; 178 case MDNS_LOG_OPERATION: syslog_level = LOG_WARNING; break; 179 case MDNS_LOG_SPS: syslog_level = LOG_NOTICE; break; 180 case MDNS_LOG_INFO: syslog_level = LOG_INFO; break; 181 case MDNS_LOG_DEBUG: syslog_level = LOG_DEBUG; break; 182 default: 183 fprintf(stderr, "Unknown loglevel %d, assuming LOG_ERR\n", loglevel); 184 fflush(stderr); 185 } 186 187 if (!log_inited) { openlog(ident, LOG_CONS, LOG_DAEMON); log_inited++; } 188 189 #if APPLE_OSX_mDNSResponder && LogTimeStamps 190 if (ident && ident[0] && mDNSPlatformClockDivisor) 191 syslog(syslog_level, "%8d.%03d: %s", (int)(t/1000), ms, buffer); 192 else 193 #elif APPLE_OSX_mDNSResponder 194 mDNSPlatformLogToFile(syslog_level, buffer); 195 #else 196 syslog(syslog_level, "%s", buffer); 197 #endif 198 } 199 } 200