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 __ANDROID__
31 #include <android/log.h>
32 #endif
33
34 #ifdef NOT_HAVE_SOCKLEN_T
35 typedef unsigned int socklen_t;
36 #endif
37
38 // Bind a UDP socket to find the source address to a destination
mDNSPlatformSourceAddrForDest(mDNSAddr * const src,const mDNSAddr * const dst)39 mDNSexport void mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst)
40 {
41 union { struct sockaddr s; struct sockaddr_in a4; struct sockaddr_in6 a6; } addr;
42 socklen_t len = sizeof(addr);
43 socklen_t inner_len = 0;
44 int sock = socket(AF_INET, SOCK_DGRAM, 0);
45 src->type = mDNSAddrType_None;
46 if (sock == -1) return;
47 if (dst->type == mDNSAddrType_IPv4)
48 {
49 inner_len = sizeof(addr.a4);
50 #ifndef NOT_HAVE_SA_LEN
51 addr.a4.sin_len = inner_len;
52 #endif
53 addr.a4.sin_family = AF_INET;
54 addr.a4.sin_port = 1; // Not important, any port will do
55 addr.a4.sin_addr.s_addr = dst->ip.v4.NotAnInteger;
56 }
57 else if (dst->type == mDNSAddrType_IPv6)
58 {
59 inner_len = sizeof(addr.a6);
60 #ifndef NOT_HAVE_SA_LEN
61 addr.a6.sin6_len = inner_len;
62 #endif
63 addr.a6.sin6_family = AF_INET6;
64 addr.a6.sin6_flowinfo = 0;
65 addr.a6.sin6_port = 1; // Not important, any port will do
66 addr.a6.sin6_addr = *(struct in6_addr*)&dst->ip.v6;
67 addr.a6.sin6_scope_id = 0;
68 }
69 else return;
70
71 if ((connect(sock, &addr.s, inner_len)) < 0)
72 { LogMsg("mDNSPlatformSourceAddrForDest: connect %#a failed errno %d (%s)", dst, errno, strerror(errno)); goto exit; }
73
74 if ((getsockname(sock, &addr.s, &len)) < 0)
75 { LogMsg("mDNSPlatformSourceAddrForDest: getsockname failed errno %d (%s)", errno, strerror(errno)); goto exit; }
76
77 src->type = dst->type;
78 if (dst->type == mDNSAddrType_IPv4) src->ip.v4.NotAnInteger = addr.a4.sin_addr.s_addr;
79 else src->ip.v6 = *(mDNSv6Addr*)&addr.a6.sin6_addr;
80 exit:
81 close(sock);
82 }
83
84 // dst must be at least MAX_ESCAPED_DOMAIN_NAME bytes, and option must be less than 32 bytes in length
GetConfigOption(char * dst,const char * option,FILE * f)85 mDNSlocal mDNSBool GetConfigOption(char *dst, const char *option, FILE *f)
86 {
87 char buf[32+1+MAX_ESCAPED_DOMAIN_NAME]; // Option name, one space, option value
88 unsigned int len = strlen(option);
89 if (len + 1 + MAX_ESCAPED_DOMAIN_NAME > sizeof(buf)-1) { LogMsg("GetConfigOption: option %s too long", option); return mDNSfalse; }
90 fseek(f, 0, SEEK_SET); // set position to beginning of stream
91 while (fgets(buf, sizeof(buf), f)) // Read at most sizeof(buf)-1 bytes from file, and append '\0' C-string terminator
92 {
93 if (!strncmp(buf, option, len))
94 {
95 strncpy(dst, buf + len + 1, MAX_ESCAPED_DOMAIN_NAME-1);
96 if (dst[MAX_ESCAPED_DOMAIN_NAME-1]) dst[MAX_ESCAPED_DOMAIN_NAME-1] = '\0';
97 len = strlen(dst);
98 if (len && dst[len-1] == '\n') dst[len-1] = '\0'; // chop newline
99 return mDNStrue;
100 }
101 }
102 debugf("Option %s not set", option);
103 return mDNSfalse;
104 }
105
ReadDDNSSettingsFromConfFile(mDNS * const m,const char * const filename,domainname * const hostname,domainname * const domain,mDNSBool * DomainDiscoveryDisabled)106 mDNSexport void ReadDDNSSettingsFromConfFile(mDNS *const m, const char *const filename, domainname *const hostname, domainname *const domain, mDNSBool *DomainDiscoveryDisabled)
107 {
108 char buf[MAX_ESCAPED_DOMAIN_NAME] = "";
109 mStatus err;
110 FILE *f = fopen(filename, "r");
111
112 if (hostname) hostname->c[0] = 0;
113 if (domain) domain->c[0] = 0;
114 if (DomainDiscoveryDisabled) *DomainDiscoveryDisabled = mDNSfalse;
115
116 if (f)
117 {
118 if (DomainDiscoveryDisabled && GetConfigOption(buf, "DomainDiscoveryDisabled", f) && !strcasecmp(buf, "true")) *DomainDiscoveryDisabled = mDNStrue;
119 if (hostname && GetConfigOption(buf, "hostname", f) && !MakeDomainNameFromDNSNameString(hostname, buf)) goto badf;
120 if (domain && GetConfigOption(buf, "zone", f) && !MakeDomainNameFromDNSNameString(domain, buf)) goto badf;
121 buf[0] = 0;
122 GetConfigOption(buf, "secret-64", f); // failure means no authentication
123 fclose(f);
124 f = NULL;
125 }
126 else
127 {
128 if (errno != ENOENT) LogMsg("ERROR: Config file exists, but cannot be opened.");
129 return;
130 }
131
132 if (domain && domain->c[0] && buf[0])
133 {
134 DomainAuthInfo *info = (DomainAuthInfo*)mDNSPlatformMemAllocate(sizeof(*info));
135 // for now we assume keyname = service reg domain and we use same key for service and hostname registration
136 err = mDNS_SetSecretForDomain(m, info, domain, domain, buf, NULL, 0, NULL);
137 if (err) LogMsg("ERROR: mDNS_SetSecretForDomain returned %d for domain %##s", err, domain->c);
138 }
139
140 return;
141
142 badf:
143 LogMsg("ERROR: malformatted config file");
144 if (f) fclose(f);
145 }
146
147 #if MDNS_DEBUGMSGS
mDNSPlatformWriteDebugMsg(const char * msg)148 mDNSexport void mDNSPlatformWriteDebugMsg(const char *msg)
149 {
150 #ifdef __ANDROID__
151 __android_log_print(ANDROID_LOG_DEBUG, "mdns", "%s", msg);
152 #else
153 fprintf(stderr,"%s\n", msg);
154 fflush(stderr);
155 #endif
156 }
157 #endif
158
mDNSPlatformWriteLogMsg(const char * ident,const char * buffer,mDNSLogLevel_t loglevel)159 mDNSexport void mDNSPlatformWriteLogMsg(const char *ident, const char *buffer, mDNSLogLevel_t loglevel)
160 {
161 #if APPLE_OSX_mDNSResponder && LogTimeStamps
162 extern mDNS mDNSStorage;
163 extern mDNSu32 mDNSPlatformClockDivisor;
164 mDNSs32 t = mDNSStorage.timenow ? mDNSStorage.timenow : mDNSPlatformClockDivisor ? mDNS_TimeNow_NoLock(&mDNSStorage) : 0;
165 int ms = ((t < 0) ? -t : t) % 1000;
166 #endif
167
168 if (mDNS_DebugMode) // In debug mode we write to stderr
169 {
170 #if APPLE_OSX_mDNSResponder && LogTimeStamps
171 if (ident && ident[0] && mDNSPlatformClockDivisor)
172 fprintf(stderr,"%8d.%03d: %s\n", (int)(t/1000), ms, buffer);
173 else
174 #endif
175 fprintf(stderr,"%s\n", buffer);
176 fflush(stderr);
177 }
178 else // else, in production mode, we write to syslog
179 {
180 static int log_inited = 0;
181
182 int syslog_level = LOG_ERR;
183 switch (loglevel)
184 {
185 case MDNS_LOG_MSG: syslog_level = LOG_ERR; break;
186 case MDNS_LOG_OPERATION: syslog_level = LOG_WARNING; break;
187 case MDNS_LOG_SPS: syslog_level = LOG_NOTICE; break;
188 case MDNS_LOG_INFO: syslog_level = LOG_INFO; break;
189 case MDNS_LOG_DEBUG: syslog_level = LOG_DEBUG; break;
190 default:
191 fprintf(stderr, "Unknown loglevel %d, assuming LOG_ERR\n", loglevel);
192 fflush(stderr);
193 }
194
195 if (!log_inited) { openlog(ident, LOG_CONS, LOG_DAEMON); log_inited++; }
196
197 #if APPLE_OSX_mDNSResponder && LogTimeStamps
198 if (ident && ident[0] && mDNSPlatformClockDivisor)
199 syslog(syslog_level, "%8d.%03d: %s", (int)(t/1000), ms, buffer);
200 else
201 #endif
202 #ifdef __ANDROID__
203 switch (loglevel)
204 {
205 case MDNS_LOG_DEBUG: syslog_level = ANDROID_LOG_DEBUG; break;
206 #if MDNS_DEBUGMSGS > 0
207 case MDNS_LOG_OPERATION: syslog_level = ANDROID_LOG_WARN; break;
208 case MDNS_LOG_SPS: syslog_level = ANDROID_LOG_DEBUG; break;
209 case MDNS_LOG_INFO: syslog_level = ANDROID_LOG_INFO; break;
210 default: syslog_level = ANDROID_LOG_ERROR; break;
211 #else
212 default: return;
213 #endif
214 }
215 __android_log_print(syslog_level, "mdns", "%s", buffer);
216 #else
217 syslog(syslog_level, "%s", buffer);
218 #endif
219 }
220 }
221