/*
* Copyright (c) 2007-2012 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 <mach/mach.h>
#include <mach/mach_error.h>
#include <mach/vm_map.h>
#include <servers/bootstrap.h>
#include <IOKit/IOReturn.h>
#include <CoreFoundation/CoreFoundation.h>
#include "mDNSDebug.h"
#include "helper.h"
#include "helpermsg.h"
#include <dispatch/dispatch.h>
#include <arpa/inet.h>
//
// Implementation Notes about the HelperQueue:
//
// To prevent blocking the main queue, all communications with mDNSResponderHelper should happen on
// HelperQueue. There are a few calls which are still synchronous and needs to be handled separately
// case by case.
//
// When spawning off the work to the HelperQueue, any arguments that are pointers need to be copied
// explicitly as they may cease to exist after the call returns. From within the block that is scheduled,
// arrays defined on the stack can't be referenced and hence it is enclosed them in a struct. If the array is
// an argument to the function, the blocks can reference them as they are passed in as pointers. But care should
// be taken to copy them locally as they may cease to exist when the function returns.
//
static dispatch_queue_t HelperQueue;
#define ERROR(x, y) y,
static const char *errorstring[] =
{
#include "helper-error.h"
NULL
};
#undef ERROR
mDNSexport mStatus mDNSHelperInit()
{
HelperQueue = dispatch_queue_create("com.apple.mDNSResponder.HelperQueue", NULL);
if (HelperQueue == NULL)
{
LogMsg("dispatch_queue_create: Helper queue NULL");
return mStatus_NoMemoryErr;
}
return mStatus_NoError;
}
static mach_port_t getHelperPort(int retry)
{
static mach_port_t port = MACH_PORT_NULL;
if (retry) port = MACH_PORT_NULL;
if (port == MACH_PORT_NULL && BOOTSTRAP_SUCCESS != bootstrap_look_up(bootstrap_port, kmDNSHelperServiceName, &port))
LogMsg("%s: cannot contact helper", __func__);
return port;
}
const char *mDNSHelperError(int err)
{
static const char *p = "<unknown error>";
if (mDNSHelperErrorBase < err && mDNSHelperErrorEnd > err)
p = errorstring[err - mDNSHelperErrorBase - 1];
return p;
}
/* Ugly but handy. */
// We don't bother reporting kIOReturnNotReady because that error code occurs in "normal" operation
// and doesn't indicate anything unexpected that needs to be investigated
#define MACHRETRYLOOP_BEGIN(kr, retry, err, fin) \
for (;;) \
{
#define MACHRETRYLOOP_END(kr, retry, err, fin) \
if (KERN_SUCCESS == (kr)) break; \
else if (MACH_SEND_INVALID_DEST == (kr) && 0 == (retry)++) continue; \
else \
{ \
(err) = kmDNSHelperCommunicationFailed; \
LogMsg("%s: Mach communication failed: %d %X %s", __func__, kr, kr, mach_error_string(kr)); \
goto fin; \
} \
} \
if (0 != (err) && kIOReturnNotReady != (err)) \
{ LogMsg("%s: %d 0x%X (%s)", __func__, (err), (err), mDNSHelperError(err)); goto fin; }
void mDNSPreferencesSetName(int key, domainlabel *old, domainlabel *new)
{
struct {
char oldname[MAX_DOMAIN_LABEL+1];
char newname[MAX_DOMAIN_LABEL+1];
} names;
mDNSPlatformMemZero(names.oldname, MAX_DOMAIN_LABEL + 1);
mDNSPlatformMemZero(names.newname, MAX_DOMAIN_LABEL + 1);
ConvertDomainLabelToCString_unescaped(old, names.oldname);
if (new) ConvertDomainLabelToCString_unescaped(new, names.newname);
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0;
int err = 0;
LogInfo("%s: oldname %s newname %s", __func__, names.oldname, names.newname);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSPreferencesSetName(getHelperPort(retry), key, names.oldname, names.newname);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
(void)err;
});
}
void mDNSRequestBPF(void)
{
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
LogInfo("%s: BPF", __func__);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSRequestBPF(getHelperPort(retry));
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
(void)err;
});
}
int mDNSPowerRequest(int key, int interval)
{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSPowerRequest(getHelperPort(retry), key, interval, &err);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
return err;
}
int mDNSSetLocalAddressCacheEntry(int ifindex, int family, const v6addr_t ip, const ethaddr_t eth)
{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSSetLocalAddressCacheEntry(getHelperPort(retry), ifindex, family, (uint8_t*)ip, (uint8_t*)eth, &err);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
return err;
}
void mDNSNotify(const char *title, const char *msg) // Both strings are UTF-8 text
{
char *titleCopy = NULL;
char *msgCopy = NULL;
if (title)
{
int len = strlen(title);
titleCopy = mDNSPlatformMemAllocate(len + 1);
if (!titleCopy)
{
LogMsg("mDNSNotify: titleCopy NULL for %s", msg);
return;
}
mDNSPlatformMemCopy(titleCopy, title, len);
titleCopy[len] = 0;
}
if (msg)
{
int len = strlen(msg);
msgCopy = mDNSPlatformMemAllocate(len + 1);
if (!msgCopy)
{
LogMsg("mDNSNotify: msgCopy NULL for %s", msg);
return;
}
mDNSPlatformMemCopy(msgCopy, msg, len);
msgCopy[len] = 0;
}
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
LogInfo("%s: title %s, msg %s", __func__, titleCopy, msgCopy);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSNotify(getHelperPort(retry), titleCopy, msgCopy);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
if (titleCopy)
mDNSPlatformMemFree(titleCopy);
if (msgCopy)
mDNSPlatformMemFree(msgCopy);
(void)err;
});
}
int mDNSKeychainGetSecrets(CFArrayRef *result)
{
CFPropertyListRef plist = NULL;
CFDataRef bytes = NULL;
kern_return_t kr = KERN_FAILURE;
unsigned int numsecrets = 0;
vm_offset_t secrets = 0;
mach_msg_type_number_t secretsCnt = 0;
int retry = 0, err = 0;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSKeychainGetSecrets(getHelperPort(retry), &numsecrets, &secrets, &secretsCnt, &err);
MACHRETRYLOOP_END(kr, retry, err, fin);
if (NULL == (bytes = CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, (void*)secrets, secretsCnt, kCFAllocatorNull)))
{
err = kmDNSHelperCreationFailed;
LogMsg("%s: CFDataCreateWithBytesNoCopy failed", __func__);
goto fin;
}
if (NULL == (plist = CFPropertyListCreateFromXMLData(kCFAllocatorDefault, bytes, kCFPropertyListImmutable, NULL)))
{
err = kmDNSHelperInvalidPList;
LogMsg("%s: CFPropertyListCreateFromXMLData failed", __func__);
goto fin;
}
if (CFArrayGetTypeID() != CFGetTypeID(plist))
{
err = kmDNSHelperTypeError;
LogMsg("%s: Unexpected result type", __func__);
CFRelease(plist);
plist = NULL;
goto fin;
}
*result = (CFArrayRef)plist;
fin:
if (bytes) CFRelease(bytes);
if (secrets) vm_deallocate(mach_task_self(), secrets, secretsCnt);
return err;
}
void mDNSConfigureServer(int updown, const char *const prefix, const domainname *const fqdn)
{
struct
{
// Assume the prefix is no larger than 10 chars
char fqdnStr[MAX_ESCAPED_DOMAIN_NAME + 10];
} name;
mDNSPlatformMemZero(name.fqdnStr, MAX_DOMAIN_LABEL + 10);
if (fqdn)
{
mDNSPlatformStrCopy(name.fqdnStr, prefix);
ConvertDomainNameToCString(fqdn, name.fqdnStr + mDNSPlatformStrLen(prefix));
}
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_SUCCESS;
int retry = 0, err = 0;
LogInfo("%s: fqdnStr %s", __func__, name.fqdnStr);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSConfigureServer(getHelperPort(retry), updown, name.fqdnStr);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
(void)err;
});
}
int mDNSAutoTunnelSetKeys(int replacedelete, v6addr_t local_inner,
v6addr_t local_outer, short local_port, v6addr_t remote_inner,
v6addr_t remote_outer, short remote_port, const char* const prefix, const domainname *const fqdn)
{
kern_return_t kr = KERN_SUCCESS;
int retry = 0, err = 0;
char fqdnStr[MAX_ESCAPED_DOMAIN_NAME + 10] = { 0 }; // Assume the prefix is no larger than 10 chars
if (fqdn)
{
mDNSPlatformStrCopy(fqdnStr, prefix);
ConvertDomainNameToCString(fqdn, fqdnStr + mDNSPlatformStrLen(prefix));
}
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSAutoTunnelSetKeys(getHelperPort(retry), replacedelete, local_inner, local_outer, local_port, remote_inner, remote_outer, remote_port, fqdnStr, &err);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
return err;
}
void mDNSSendWakeupPacket(unsigned ifid, char *eth_addr, char *ip_addr, int iteration)
{
char *ip_addr_copy = NULL;
char *eth_addr_copy = NULL;
if (eth_addr)
{
int len = strlen(eth_addr);
eth_addr_copy = mDNSPlatformMemAllocate(len + 1);
if (!eth_addr_copy)
{
LogMsg("mDNSSendWakeupPacket: eth_addr_copy NULL for %s", eth_addr);
return;
}
mDNSPlatformMemCopy(eth_addr_copy, eth_addr, len);
eth_addr_copy[len] = 0;
}
if (ip_addr)
{
int len = strlen(ip_addr);
ip_addr_copy = mDNSPlatformMemAllocate(len + 1);
if (!ip_addr_copy)
{
LogMsg("mDNSSendWakeupPacket: ip_addr_copy NULL for %s", ip_addr);
return;
}
mDNSPlatformMemCopy(ip_addr_copy, ip_addr, len);
ip_addr_copy[len] = 0;
}
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_SUCCESS;
int retry = 0, err = 0;
LogInfo("%s: Entered ethernet address %s, ip address %s", __func__, eth_addr_copy, ip_addr_copy);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSSendWakeupPacket(getHelperPort(retry), ifid, eth_addr_copy, ip_addr_copy, iteration);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
if (eth_addr_copy)
mDNSPlatformMemFree(eth_addr_copy);
if (ip_addr_copy)
mDNSPlatformMemFree(ip_addr_copy);
(void) err;
});
}
void mDNSPacketFilterControl(uint32_t command, char * ifname, uint32_t count, pfArray_t portArray, pfArray_t protocolArray)
{
struct
{
pfArray_t portArray;
pfArray_t protocolArray;
} pfa;
char *ifnameCopy = NULL;
mDNSPlatformMemCopy(pfa.portArray, portArray, sizeof(pfArray_t));
mDNSPlatformMemCopy(pfa.protocolArray, protocolArray, sizeof(pfArray_t));
if (ifname)
{
int len = strlen(ifname);
ifnameCopy = mDNSPlatformMemAllocate(len + 1);
if (!ifnameCopy)
{
LogMsg("mDNSPacketFilterControl: ifnameCopy NULL");
return;
}
mDNSPlatformMemCopy(ifnameCopy, ifname, len);
ifnameCopy[len] = 0;
}
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_SUCCESS;
int retry = 0, err = 0;
LogInfo("%s, ifname %s", __func__, ifnameCopy);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSPacketFilterControl(getHelperPort(retry), command, ifnameCopy, count, (uint16_t *)pfa.portArray, (uint16_t *)pfa.protocolArray);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
if (ifnameCopy)
mDNSPlatformMemFree(ifnameCopy);
(void) err;
});
}
void mDNSSendKeepalive(v6addr_t sadd, v6addr_t dadd, uint16_t lport, uint16_t rport, unsigned seq, unsigned ack, uint16_t win)
{
struct
{
v6addr_t sadd;
v6addr_t dadd;
} addr;
mDNSPlatformMemCopy(addr.sadd, sadd, sizeof(v6addr_t));
mDNSPlatformMemCopy(addr.dadd, dadd, sizeof(v6addr_t));
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
char buf1[INET6_ADDRSTRLEN];
char buf2[INET6_ADDRSTRLEN];
buf1[0] = 0;
buf2[0] = 0;
inet_ntop(AF_INET6, addr.sadd, buf1, sizeof(buf1));
inet_ntop(AF_INET6, addr.dadd, buf2, sizeof(buf2));
LogInfo("%s: sadd is %s, dadd is %s", __func__, buf1, buf2);
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSSendKeepalive(getHelperPort(retry), (uint8_t *)addr.sadd, (uint8_t *)addr.dadd, lport, rport, seq, ack, win);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
(void) err;
});
}
int mDNSRetrieveTCPInfo(int family, v6addr_t laddr, uint16_t lport, v6addr_t raddr, uint16_t rport, uint32_t *seq, uint32_t *ack, uint16_t *win, int32_t *intfid)
{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSRetrieveTCPInfo(getHelperPort(retry), family, (uint8_t *)laddr, lport, (uint8_t *)raddr, rport, seq, ack, win, intfid);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
return err;
}
void mDNSGetRemoteMAC(mDNS *const m, int family, v6addr_t raddr)
{
struct {
v6addr_t addr;
} dst;
mDNSPlatformMemCopy(dst.addr, raddr, sizeof(v6addr_t));
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
ethaddr_t eth;
IPAddressMACMapping *addrMapping;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSGetRemoteMAC(getHelperPort(retry), family, (uint8_t *)dst.addr, eth);
MACHRETRYLOOP_END(kr, retry, err, fin);
// If the call to get the remote MAC address succeeds, allocate and copy
// the values and schedule a task to update the MAC address in the TCP Keepalive record.
if (kr == KERN_SUCCESS)
{
addrMapping = (IPAddressMACMapping *)malloc(sizeof(IPAddressMACMapping));
snprintf(addrMapping->ethaddr, sizeof(addrMapping->ethaddr), "%02x:%02x:%02x:%02x:%02x:%02x",
eth[0], eth[1], eth[2], eth[3], eth[4], eth[5]);
if (family == AF_INET)
{
addrMapping->ipaddr.type = mDNSAddrType_IPv4;
mDNSPlatformMemCopy(addrMapping->ipaddr.ip.v4.b, dst.addr, sizeof(v6addr_t));
}
else
{
addrMapping->ipaddr.type = mDNSAddrType_IPv6;
mDNSPlatformMemCopy(addrMapping->ipaddr.ip.v6.b, dst.addr, sizeof(v6addr_t));
}
mDNSPlatformDispatchAsync(m, addrMapping, UpdateRMACCallback);
}
fin:
(void) err;
});
}
void mDNSStoreSPSMACAddress(int family, v6addr_t spsaddr, char *ifname)
{
struct {
v6addr_t saddr;
} addr;
mDNSPlatformMemCopy(addr.saddr, spsaddr, sizeof(v6addr_t));
dispatch_async(HelperQueue, ^{
kern_return_t kr = KERN_FAILURE;
int retry = 0, err = 0;
MACHRETRYLOOP_BEGIN(kr, retry, err, fin);
kr = proxy_mDNSStoreSPSMACAddress(getHelperPort(retry), family, (uint8_t *)addr.saddr, ifname);
MACHRETRYLOOP_END(kr, retry, err, fin);
fin:
(void)err;
});
}