/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2004-2015 Apple Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h> // Needed for fopen() etc.
#include <unistd.h> // Needed for close()
#include <string.h> // Needed for strlen() etc.
#include <errno.h> // Needed for errno etc.
#include <sys/socket.h> // Needed for socket() etc.
#include <netinet/in.h> // Needed for sockaddr_in
#include <syslog.h>
#if APPLE_OSX_mDNSResponder
#include <os/log.h>
#endif
#include "mDNSEmbeddedAPI.h" // Defines the interface provided to the client layer above
#include "DNSCommon.h"
#include "PlatformCommon.h"
#ifdef NOT_HAVE_SOCKLEN_T
typedef unsigned int socklen_t;
#endif
// Bind a UDP socket to find the source address to a destination
mDNSexport void mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst)
{
union { struct sockaddr s; struct sockaddr_in a4; struct sockaddr_in6 a6; } addr;
socklen_t len = sizeof(addr);
socklen_t inner_len = 0;
int sock = socket(AF_INET, SOCK_DGRAM, 0);
src->type = mDNSAddrType_None;
if (sock == -1) return;
memset(&addr, 0, sizeof(addr));
if (dst->type == mDNSAddrType_IPv4)
{
inner_len = sizeof(addr.a4);
#ifndef NOT_HAVE_SA_LEN
addr.a4.sin_len = inner_len;
#endif
addr.a4.sin_family = AF_INET;
addr.a4.sin_port = 7; // Not important, any port will do
addr.a4.sin_addr.s_addr = dst->ip.v4.NotAnInteger;
}
else if (dst->type == mDNSAddrType_IPv6)
{
inner_len = sizeof(addr.a6);
#ifndef NOT_HAVE_SA_LEN
addr.a6.sin6_len = inner_len;
#endif
addr.a6.sin6_family = AF_INET6;
addr.a6.sin6_flowinfo = 0;
addr.a6.sin6_port = 7; // Not important, any port will do
addr.a6.sin6_addr = *(struct in6_addr*)&dst->ip.v6;
addr.a6.sin6_scope_id = 0;
}
else return;
if ((connect(sock, &addr.s, inner_len)) < 0)
{
static mDNSv4Addr dummy = { 198, 51, 100, 42 };
// Don't spam if we can't connect to 198.51.100.42 to the console.
// That is our test address to out which interfaces/address should be primary and is also
// configured in mDNSPosix/PosixDaemon.c:Reconfigure()
// Failing to connect to it with EADDRNOTAVAIL is a common situation, especially on boot up.
if (dst->type == mDNSAddrType_IPv4 && dst->ip.v4.NotAnInteger == dummy.NotAnInteger && errno == EADDRNOTAVAIL)
LogInfo("mDNSPlatformSourceAddrForDest: connect %#a failed errno %d (%s)", dst, errno, strerror(errno));
else
LogMsg("mDNSPlatformSourceAddrForDest: connect %#a failed errno %d (%s)", dst, errno, strerror(errno));
goto exit;
}
if ((getsockname(sock, &addr.s, &len)) < 0)
{ LogMsg("mDNSPlatformSourceAddrForDest: getsockname failed errno %d (%s)", errno, strerror(errno)); goto exit; }
src->type = dst->type;
if (dst->type == mDNSAddrType_IPv4) src->ip.v4.NotAnInteger = addr.a4.sin_addr.s_addr;
else src->ip.v6 = *(mDNSv6Addr*)&addr.a6.sin6_addr;
exit:
close(sock);
}
// dst must be at least MAX_ESCAPED_DOMAIN_NAME bytes, and option must be less than 32 bytes in length
mDNSlocal mDNSBool GetConfigOption(char *dst, const char *option, FILE *f)
{
char buf[32+1+MAX_ESCAPED_DOMAIN_NAME]; // Option name, one space, option value
unsigned int len = strlen(option);
if (len + 1 + MAX_ESCAPED_DOMAIN_NAME > sizeof(buf)-1) { LogMsg("GetConfigOption: option %s too long", option); return mDNSfalse; }
fseek(f, 0, SEEK_SET); // set position to beginning of stream
while (fgets(buf, sizeof(buf), f)) // Read at most sizeof(buf)-1 bytes from file, and append '\0' C-string terminator
{
if (!strncmp(buf, option, len))
{
strncpy(dst, buf + len + 1, MAX_ESCAPED_DOMAIN_NAME-1);
if (dst[MAX_ESCAPED_DOMAIN_NAME-1]) dst[MAX_ESCAPED_DOMAIN_NAME-1] = '\0';
len = strlen(dst);
if (len && dst[len-1] == '\n') dst[len-1] = '\0'; // chop newline
return mDNStrue;
}
}
debugf("Option %s not set", option);
return mDNSfalse;
}
mDNSexport void ReadDDNSSettingsFromConfFile(mDNS *const m, const char *const filename, domainname *const hostname, domainname *const domain, mDNSBool *DomainDiscoveryDisabled)
{
char buf[MAX_ESCAPED_DOMAIN_NAME] = "";
mStatus err;
FILE *f = fopen(filename, "r");
if (hostname) hostname->c[0] = 0;
if (domain) domain->c[0] = 0;
if (DomainDiscoveryDisabled) *DomainDiscoveryDisabled = mDNSfalse;
if (f)
{
if (DomainDiscoveryDisabled && GetConfigOption(buf, "DomainDiscoveryDisabled", f) && !strcasecmp(buf, "true")) *DomainDiscoveryDisabled = mDNStrue;
if (hostname && GetConfigOption(buf, "hostname", f) && !MakeDomainNameFromDNSNameString(hostname, buf)) goto badf;
if (domain && GetConfigOption(buf, "zone", f) && !MakeDomainNameFromDNSNameString(domain, buf)) goto badf;
buf[0] = 0;
GetConfigOption(buf, "secret-64", f); // failure means no authentication
fclose(f);
f = NULL;
}
else
{
if (errno != ENOENT) LogMsg("ERROR: Config file exists, but cannot be opened.");
return;
}
if (domain && domain->c[0] && buf[0])
{
DomainAuthInfo *info = (DomainAuthInfo*)mDNSPlatformMemAllocate(sizeof(*info));
// for now we assume keyname = service reg domain and we use same key for service and hostname registration
err = mDNS_SetSecretForDomain(m, info, domain, domain, buf, NULL, 0, mDNSfalse);
if (err) LogMsg("ERROR: mDNS_SetSecretForDomain returned %d for domain %##s", err, domain->c);
}
return;
badf:
LogMsg("ERROR: malformatted config file");
if (f) fclose(f);
}
#if MDNS_DEBUGMSGS
mDNSexport void mDNSPlatformWriteDebugMsg(const char *msg)
{
fprintf(stderr,"%s\n", msg);
fflush(stderr);
}
#endif
mDNSexport void mDNSPlatformWriteLogMsg(const char *ident, const char *buffer, mDNSLogLevel_t loglevel)
{
#if APPLE_OSX_mDNSResponder && LogTimeStamps
extern mDNS mDNSStorage;
extern mDNSu32 mDNSPlatformClockDivisor;
mDNSs32 t = mDNSStorage.timenow ? mDNSStorage.timenow : mDNSPlatformClockDivisor ? mDNS_TimeNow_NoLock(&mDNSStorage) : 0;
int ms = ((t < 0) ? -t : t) % 1000;
#endif
if (mDNS_DebugMode) // In debug mode we write to stderr
{
#if APPLE_OSX_mDNSResponder && LogTimeStamps
if (ident && ident[0] && mDNSPlatformClockDivisor)
fprintf(stderr,"%8d.%03d: %s\n", (int)(t/1000), ms, buffer);
else
#endif
fprintf(stderr,"%s\n", buffer);
fflush(stderr);
}
else // else, in production mode, we write to syslog
{
static int log_inited = 0;
int syslog_level = LOG_ERR;
switch (loglevel)
{
#if APPLE_OSX_mDNSResponder
case MDNS_LOG_MSG: syslog_level = OS_LOG_TYPE_DEFAULT; break;
case MDNS_LOG_OPERATION: syslog_level = OS_LOG_TYPE_INFO; break;
case MDNS_LOG_SPS: syslog_level = OS_LOG_TYPE_INFO; break;
case MDNS_LOG_INFO: syslog_level = OS_LOG_TYPE_INFO; break;
case MDNS_LOG_DEBUG: syslog_level = OS_LOG_TYPE_DEBUG; break;
default: syslog_level = OS_LOG_TYPE_DEFAULT; break;
#else
case MDNS_LOG_MSG: syslog_level = LOG_ERR; break;
case MDNS_LOG_OPERATION: syslog_level = LOG_WARNING; break;
case MDNS_LOG_SPS: syslog_level = LOG_NOTICE; break;
case MDNS_LOG_INFO: syslog_level = LOG_INFO; break;
case MDNS_LOG_DEBUG: syslog_level = LOG_DEBUG; break;
default:
fprintf(stderr, "Unknown loglevel %d, assuming LOG_ERR\n", loglevel);
fflush(stderr);
#endif
}
if (!log_inited) { openlog(ident, LOG_CONS, LOG_DAEMON); log_inited++; }
#if APPLE_OSX_mDNSResponder && LogTimeStamps
if (ident && ident[0] && mDNSPlatformClockDivisor)
syslog(syslog_level, "%8d.%03d: %s", (int)(t/1000), ms, buffer);
else
#endif
{
#if APPLE_OSX_mDNSResponder
mDNSPlatformLogToFile(syslog_level, buffer);
#else
syslog(syslog_level, "%s", buffer);
#endif
}
}
}