ZeroTierOne/node/EthernetTap.cpp

1783 lines
54 KiB
C++

/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2011-2014 ZeroTier Networks LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include "Constants.hpp"
#include "EthernetTap.hpp"
#include "Logger.hpp"
#include "RuntimeEnvironment.hpp"
#include "Utils.hpp"
#include "Mutex.hpp"
#include "Utils.hpp"
// ff:ff:ff:ff:ff:ff with no ADI
static const ZeroTier::MulticastGroup _blindWildcardMulticastGroup(ZeroTier::MAC(0xff),0);
//
// TAP implementation for *nix OSes, with some specialization for different flavors
//
#ifdef __UNIX_LIKE__ /////////////////////////////////////////////////////////
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/select.h>
#include <netinet/in.h>
#include <net/if_arp.h>
#include <arpa/inet.h>
// Command identifiers used with command finder static (on various *nixes)
#define ZT_UNIX_IP_COMMAND 1
#define ZT_UNIX_IFCONFIG_COMMAND 2
#define ZT_MAC_KEXTLOAD_COMMAND 3
#define ZT_MAC_KEXTUNLOAD_COMMAND 4
// Finds external commands on startup
class _CommandFinder
{
public:
_CommandFinder()
{
_findCmd(ZT_UNIX_IFCONFIG_COMMAND,"ifconfig");
#ifdef __LINUX__
_findCmd(ZT_UNIX_IP_COMMAND,"ip");
#endif
#ifdef __APPLE__
_findCmd(ZT_MAC_KEXTLOAD_COMMAND,"kextload");
_findCmd(ZT_MAC_KEXTUNLOAD_COMMAND,"kextunload");
#endif
}
// returns NULL if command was not found
inline const char *operator[](int id) const
throw()
{
std::map<int,std::string>::const_iterator c(_paths.find(id));
if (c == _paths.end())
return (const char *)0;
return c->second.c_str();
}
private:
inline void _findCmd(int id,const char *name)
{
char tmp[4096];
ZeroTier::Utils::snprintf(tmp,sizeof(tmp),"/sbin/%s",name);
if (ZeroTier::Utils::fileExists(tmp)) {
_paths[id] = tmp;
return;
}
ZeroTier::Utils::snprintf(tmp,sizeof(tmp),"/usr/sbin/%s",name);
if (ZeroTier::Utils::fileExists(tmp)) {
_paths[id] = tmp;
return;
}
ZeroTier::Utils::snprintf(tmp,sizeof(tmp),"/bin/%s",name);
if (ZeroTier::Utils::fileExists(tmp)) {
_paths[id] = tmp;
return;
}
ZeroTier::Utils::snprintf(tmp,sizeof(tmp),"/usr/bin/%s",name);
if (ZeroTier::Utils::fileExists(tmp)) {
_paths[id] = tmp;
return;
}
}
std::map<int,std::string> _paths;
};
static const _CommandFinder UNIX_COMMANDS;
#ifdef __LINUX__
#include <linux/if.h>
#include <linux/if_tun.h>
#include <linux/if_addr.h>
#include <linux/if_ether.h>
#include <ifaddrs.h>
#endif // __LINUX__
#ifdef __APPLE__
#include <sys/cdefs.h>
#include <sys/uio.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/route.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
struct prf_ra { // stupid OSX compile fix... in6_var defines this in a struct which namespaces it for C++
u_char onlink : 1;
u_char autonomous : 1;
u_char reserved : 6;
} prf_ra;
#include <netinet6/in6_var.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#include <ifaddrs.h>
// These are KERNEL_PRIVATE... why?
#ifndef SIOCAUTOCONF_START
#define SIOCAUTOCONF_START _IOWR('i', 132, struct in6_ifreq) /* accept rtadvd on this interface */
#endif
#ifndef SIOCAUTOCONF_STOP
#define SIOCAUTOCONF_STOP _IOWR('i', 133, struct in6_ifreq) /* stop accepting rtadv for this interface */
#endif
static volatile int EthernetTap_instances = 0;
static ZeroTier::Mutex EthernetTap_instances_m;
static inline bool _setIpv6Stuff(const char *ifname,bool performNUD,bool acceptRouterAdverts)
{
struct in6_ndireq nd;
struct in6_ifreq ifr;
int s = socket(AF_INET6,SOCK_DGRAM,0);
if (s <= 0)
return false;
memset(&nd,0,sizeof(nd));
strncpy(nd.ifname,ifname,sizeof(nd.ifname));
if (ioctl(s,SIOCGIFINFO_IN6,&nd)) {
close(s);
return false;
}
unsigned long oldFlags = (unsigned long)nd.ndi.flags;
if (performNUD)
nd.ndi.flags |= ND6_IFF_PERFORMNUD;
else nd.ndi.flags &= ~ND6_IFF_PERFORMNUD;
if (oldFlags != (unsigned long)nd.ndi.flags) {
if (ioctl(s,SIOCSIFINFO_FLAGS,&nd)) {
close(s);
return false;
}
}
memset(&ifr,0,sizeof(ifr));
strncpy(ifr.ifr_name,ifname,sizeof(ifr.ifr_name));
if (ioctl(s,acceptRouterAdverts ? SIOCAUTOCONF_START : SIOCAUTOCONF_STOP,&ifr)) {
close(s);
return false;
}
close(s);
return true;
}
#endif // __APPLE__
namespace ZeroTier {
// Only permit one tap to be opened concurrently across the entire process
static Mutex __tapCreateLock;
#ifdef __LINUX__
EthernetTap::EthernetTap(
const RuntimeEnvironment *renv,
const char *tag,
const MAC &mac,
unsigned int mtu,
void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
void *arg)
throw(std::runtime_error) :
_mac(mac),
_mtu(mtu),
_r(renv),
_handler(handler),
_arg(arg),
_fd(0)
{
char procpath[128];
struct stat sbuf;
Mutex::Lock _l(__tapCreateLock); // create only one tap at a time, globally
if (mtu > 4096)
throw std::runtime_error("max tap MTU is 4096");
_fd = ::open("/dev/net/tun",O_RDWR);
if (_fd <= 0)
throw std::runtime_error(std::string("could not open TUN/TAP device: ") + strerror(errno));
struct ifreq ifr;
memset(&ifr,0,sizeof(ifr));
// Try to recall our last device name, or pick an unused one if that fails.
bool recalledDevice = false;
if ((tag)&&(tag[0])) {
Utils::scopy(ifr.ifr_name,sizeof(ifr.ifr_name),tag);
Utils::snprintf(procpath,sizeof(procpath),"/proc/sys/net/ipv4/conf/%s",ifr.ifr_name);
recalledDevice = (stat(procpath,&sbuf) != 0);
}
if (!recalledDevice) {
int devno = 0;
do {
Utils::snprintf(ifr.ifr_name,sizeof(ifr.ifr_name),"zt%d",devno++);
Utils::snprintf(procpath,sizeof(procpath),"/proc/sys/net/ipv4/conf/%s",ifr.ifr_name);
} while (stat(procpath,&sbuf) == 0); // try zt#++ until we find one that does not exist
}
ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
if (ioctl(_fd,TUNSETIFF,(void *)&ifr) < 0) {
::close(_fd);
throw std::runtime_error("unable to configure TUN/TAP device for TAP operation");
}
strcpy(_dev,ifr.ifr_name);
ioctl(_fd,TUNSETPERSIST,0); // valgrind may generate a false alarm here
// Open an arbitrary socket to talk to netlink
int sock = socket(AF_INET,SOCK_DGRAM,0);
if (sock <= 0) {
::close(_fd);
throw std::runtime_error("unable to open netlink socket");
}
// Set MAC address
ifr.ifr_ifru.ifru_hwaddr.sa_family = ARPHRD_ETHER;
memcpy(ifr.ifr_ifru.ifru_hwaddr.sa_data,mac.data,6);
if (ioctl(sock,SIOCSIFHWADDR,(void *)&ifr) < 0) {
::close(_fd);
::close(sock);
throw std::runtime_error("unable to configure TAP hardware (MAC) address");
return;
}
// Set MTU
ifr.ifr_ifru.ifru_mtu = (int)mtu;
if (ioctl(sock,SIOCSIFMTU,(void *)&ifr) < 0) {
::close(_fd);
::close(sock);
throw std::runtime_error("unable to configure TAP MTU");
}
if (fcntl(_fd,F_SETFL,fcntl(_fd,F_GETFL) & ~O_NONBLOCK) == -1) {
::close(_fd);
throw std::runtime_error("unable to set flags on file descriptor for TAP device");
}
/* Bring interface up */
if (ioctl(sock,SIOCGIFFLAGS,(void *)&ifr) < 0) {
::close(_fd);
::close(sock);
throw std::runtime_error("unable to get TAP interface flags");
}
ifr.ifr_flags |= IFF_UP;
if (ioctl(sock,SIOCSIFFLAGS,(void *)&ifr) < 0) {
::close(_fd);
::close(sock);
throw std::runtime_error("unable to set TAP interface flags");
}
::close(sock);
::pipe(_shutdownSignalPipe);
TRACE("tap %s created",_dev);
_thread = Thread::start(this);
}
#endif // __LINUX__
#ifdef __APPLE__
EthernetTap::EthernetTap(
const RuntimeEnvironment *renv,
const char *tag,
const MAC &mac,
unsigned int mtu,
void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
void *arg)
throw(std::runtime_error) :
_mac(mac),
_mtu(mtu),
_r(renv),
_handler(handler),
_arg(arg),
_fd(0)
{
char devpath[64],ethaddr[64],mtustr[16],tmp[4096];
struct stat stattmp;
Mutex::Lock _l(__tapCreateLock); // create only one tap at a time, globally
if (mtu > 4096)
throw std::runtime_error("max tap MTU is 4096");
// Check for existence of ZT tap devices, try to load module if not there
const char *kextload = UNIX_COMMANDS[ZT_MAC_KEXTLOAD_COMMAND];
if ((stat("/dev/zt0",&stattmp))&&(kextload)) {
strcpy(tmp,_r->homePath.c_str());
long kextpid = (long)vfork();
if (kextpid == 0) {
chdir(tmp);
execl(kextload,kextload,"-q","-repository",tmp,"tap.kext",(const char *)0);
_exit(-1);
} else if (kextpid > 0) {
int exitcode = -1;
waitpid(kextpid,&exitcode,0);
usleep(500);
} else throw std::runtime_error("unable to create subprocess with fork()");
}
if (stat("/dev/zt0",&stattmp))
throw std::runtime_error("/dev/zt# tap devices do not exist and unable to load kernel extension");
// Try to reopen the last device we had, if we had one and it's still unused.
bool recalledDevice = false;
if ((tag)&&(tag[0])) {
Utils::snprintf(devpath,sizeof(devpath),"/dev/%s",tag);
if (stat(devpath,&stattmp) == 0) {
_fd = ::open(devpath,O_RDWR);
if (_fd > 0) {
Utils::scopy(_dev,sizeof(_dev),tag);
recalledDevice = true;
}
}
}
// Open the first unused tap device if we didn't recall a previous one.
if (!recalledDevice) {
for(int i=0;i<256;++i) {
Utils::snprintf(devpath,sizeof(devpath),"/dev/zt%d",i);
if (stat(devpath,&stattmp))
throw std::runtime_error("no more TAP devices available");
_fd = ::open(devpath,O_RDWR);
if (_fd > 0) {
Utils::snprintf(_dev,sizeof(_dev),"zt%d",i);
break;
}
}
}
if (_fd <= 0)
throw std::runtime_error("unable to open TAP device or no more devices available");
if (fcntl(_fd,F_SETFL,fcntl(_fd,F_GETFL) & ~O_NONBLOCK) == -1) {
::close(_fd);
throw std::runtime_error("unable to set flags on file descriptor for TAP device");
}
const char *ifconfig = UNIX_COMMANDS[ZT_UNIX_IFCONFIG_COMMAND];
if (!ifconfig) {
::close(_fd);
throw std::runtime_error("unable to find 'ifconfig' command on system");
}
// Configure MAC address and MTU, bring interface up
Utils::snprintf(ethaddr,sizeof(ethaddr),"%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",(int)mac[0],(int)mac[1],(int)mac[2],(int)mac[3],(int)mac[4],(int)mac[5]);
Utils::snprintf(mtustr,sizeof(mtustr),"%u",mtu);
long cpid;
if ((cpid = (long)vfork()) == 0) {
execl(ifconfig,ifconfig,_dev,"lladdr",ethaddr,"mtu",mtustr,"up",(const char *)0);
_exit(-1);
} else {
int exitcode = -1;
waitpid(cpid,&exitcode,0);
if (exitcode) {
::close(_fd);
throw std::runtime_error("ifconfig failure setting link-layer address and activating tap interface");
}
}
_setIpv6Stuff(_dev,true,false);
::pipe(_shutdownSignalPipe);
_thread = Thread::start(this);
EthernetTap_instances_m.lock();
++EthernetTap_instances;
EthernetTap_instances_m.unlock();
}
#endif // __APPLE__
EthernetTap::~EthernetTap()
{
::write(_shutdownSignalPipe[1],"\0",1); // causes thread to exit
Thread::join(_thread);
::close(_fd);
#ifdef __APPLE__
EthernetTap_instances_m.lock();
int instances = --EthernetTap_instances;
EthernetTap_instances_m.unlock();
if (instances <= 0) {
// Unload OSX kernel extension on the deletion of the last EthernetTap
// instance.
const char *kextunload = UNIX_COMMANDS[ZT_MAC_KEXTUNLOAD_COMMAND];
if (kextunload) {
char tmp[4096];
sprintf(tmp,"%s/tap.kext",_r->homePath.c_str());
long kextpid = (long)vfork();
if (kextpid == 0) {
execl(kextunload,kextunload,tmp,(const char *)0);
_exit(-1);
} else if (kextpid > 0) {
int exitcode = -1;
waitpid(kextpid,&exitcode,0);
}
}
}
#endif // __APPLE__
}
void EthernetTap::setDisplayName(const char *dn)
{
}
#ifdef __LINUX__
static bool ___removeIp(const char *_dev,const InetAddress &ip)
{
const char *ipcmd = UNIX_COMMANDS[ZT_UNIX_IP_COMMAND];
if (!ipcmd)
return false;
long cpid = (long)vfork();
if (cpid == 0) {
execl(ipcmd,ipcmd,"addr","del",ip.toString().c_str(),"dev",_dev,(const char *)0);
_exit(-1);
} else {
int exitcode = -1;
waitpid(cpid,&exitcode,0);
return (exitcode == 0);
}
}
bool EthernetTap::addIP(const InetAddress &ip)
{
const char *ipcmd = UNIX_COMMANDS[ZT_UNIX_IP_COMMAND];
if (!ipcmd) {
LOG("ERROR: could not configure IP address for %s: unable to find 'ip' command on system (checked /sbin, /bin, /usr/sbin, /usr/bin)",_dev);
return false;
}
if (!ip)
return false;
std::set<InetAddress> allIps(ips());
if (allIps.count(ip) > 0)
return true;
// Remove and reconfigure if address is the same but netmask is different
for(std::set<InetAddress>::iterator i(allIps.begin());i!=allIps.end();++i) {
if (i->ipsEqual(ip)) {
if (___removeIp(_dev,*i)) {
break;
} else {
LOG("WARNING: failed to remove old IP/netmask %s to replace with %s",i->toString().c_str(),ip.toString().c_str());
}
}
}
long cpid;
if ((cpid = (long)vfork()) == 0) {
execl(ipcmd,ipcmd,"addr","add",ip.toString().c_str(),"dev",_dev,(const char *)0);
_exit(-1);
} else if (cpid > 0) {
int exitcode = -1;
waitpid(cpid,&exitcode,0);
return (exitcode == 0);
}
return false;
}
#endif // __LINUX__
#ifdef __APPLE__
static bool ___removeIp(const char *_dev,const InetAddress &ip)
{
const char *ifconfig = UNIX_COMMANDS[ZT_UNIX_IFCONFIG_COMMAND];
if (!ifconfig)
return false;
long cpid;
if ((cpid = (long)vfork()) == 0) {
execl(ifconfig,ifconfig,_dev,"inet",ip.toIpString().c_str(),"-alias",(const char *)0);
_exit(-1);
} else {
int exitcode = -1;
waitpid(cpid,&exitcode,0);
return (exitcode == 0);
}
return false; // never reached, make compiler shut up about return value
}
bool EthernetTap::addIP(const InetAddress &ip)
{
const char *ifconfig = UNIX_COMMANDS[ZT_UNIX_IFCONFIG_COMMAND];
if (!ifconfig) {
LOG("ERROR: could not configure IP address for %s: unable to find 'ifconfig' command on system (checked /sbin, /bin, /usr/sbin, /usr/bin)",_dev);
return false;
}
if (!ip)
return false;
std::set<InetAddress> allIps(ips());
if (allIps.count(ip) > 0)
return true; // IP/netmask already assigned
// Remove and reconfigure if address is the same but netmask is different
for(std::set<InetAddress>::iterator i(allIps.begin());i!=allIps.end();++i) {
if ((i->ipsEqual(ip))&&(i->netmaskBits() != ip.netmaskBits())) {
if (___removeIp(_dev,*i)) {
break;
} else {
LOG("WARNING: failed to remove old IP/netmask %s to replace with %s",i->toString().c_str(),ip.toString().c_str());
}
}
}
long cpid;
if ((cpid = (long)vfork()) == 0) {
execl(ifconfig,ifconfig,_dev,ip.isV4() ? "inet" : "inet6",ip.toString().c_str(),"alias",(const char *)0);
_exit(-1);
} else {
int exitcode = -1;
waitpid(cpid,&exitcode,0);
return (exitcode == 0);
}
return false;
}
#endif // __APPLE__
bool EthernetTap::removeIP(const InetAddress &ip)
{
if (ips().count(ip) > 0) {
if (___removeIp(_dev,ip))
return true;
}
return false;
}
std::set<InetAddress> EthernetTap::ips() const
{
struct ifaddrs *ifa = (struct ifaddrs *)0;
if (getifaddrs(&ifa))
return std::set<InetAddress>();
std::set<InetAddress> r;
struct ifaddrs *p = ifa;
while (p) {
if ((!strcmp(p->ifa_name,_dev))&&(p->ifa_addr)&&(p->ifa_netmask)&&(p->ifa_addr->sa_family == p->ifa_netmask->sa_family)) {
switch(p->ifa_addr->sa_family) {
case AF_INET: {
struct sockaddr_in *sin = (struct sockaddr_in *)p->ifa_addr;
struct sockaddr_in *nm = (struct sockaddr_in *)p->ifa_netmask;
r.insert(InetAddress(&(sin->sin_addr.s_addr),4,Utils::countBits((uint32_t)nm->sin_addr.s_addr)));
} break;
case AF_INET6: {
struct sockaddr_in6 *sin = (struct sockaddr_in6 *)p->ifa_addr;
struct sockaddr_in6 *nm = (struct sockaddr_in6 *)p->ifa_netmask;
uint32_t b[4];
memcpy(b,nm->sin6_addr.s6_addr,sizeof(b));
r.insert(InetAddress(sin->sin6_addr.s6_addr,16,Utils::countBits(b[0]) + Utils::countBits(b[1]) + Utils::countBits(b[2]) + Utils::countBits(b[3])));
} break;
}
}
p = p->ifa_next;
}
if (ifa)
freeifaddrs(ifa);
return r;
}
void EthernetTap::put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len)
{
char putBuf[4096 + 14];
if ((_fd > 0)&&(len <= _mtu)) {
for(int i=0;i<6;++i)
putBuf[i] = to.data[i];
for(int i=0;i<6;++i)
putBuf[i+6] = from.data[i];
*((uint16_t *)(putBuf + 12)) = htons((uint16_t)etherType);
memcpy(putBuf + 14,data,len);
len += 14;
int n = ::write(_fd,putBuf,len);
if (n <= 0) {
LOG("error writing packet to Ethernet tap device: %s",strerror(errno));
} else if (n != (int)len) {
// Saw this gremlin once, so log it if we see it again... OSX tap
// or something seems to have goofy issues with certain MTUs.
LOG("ERROR: write underrun: %s tap write() wrote %d of %u bytes of frame",_dev,n,len);
}
}
}
std::string EthernetTap::deviceName() const
{
return std::string(_dev);
}
std::string EthernetTap::persistentId() const
{
return std::string();
}
#ifdef __LINUX__
bool EthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
{
char *ptr,*ptr2;
unsigned char mac[6];
std::set<MulticastGroup> newGroups;
int fd = ::open("/proc/net/dev_mcast",O_RDONLY);
if (fd > 0) {
char buf[131072];
int n = (int)::read(fd,buf,sizeof(buf));
if ((n > 0)&&(n < (int)sizeof(buf))) {
buf[n] = (char)0;
for(char *l=strtok_r(buf,"\r\n",&ptr);(l);l=strtok_r((char *)0,"\r\n",&ptr)) {
int fno = 0;
char *devname = (char *)0;
char *mcastmac = (char *)0;
for(char *f=strtok_r(l," \t",&ptr2);(f);f=strtok_r((char *)0," \t",&ptr2)) {
if (fno == 1)
devname = f;
else if (fno == 4)
mcastmac = f;
++fno;
}
if ((devname)&&(!strcmp(devname,_dev))&&(mcastmac)&&(Utils::unhex(mcastmac,mac,6) == 6))
newGroups.insert(MulticastGroup(MAC(mac),0));
}
}
::close(fd);
}
{
std::set<InetAddress> allIps(ips());
for(std::set<InetAddress>::const_iterator i(allIps.begin());i!=allIps.end();++i)
newGroups.insert(MulticastGroup::deriveMulticastGroupForAddressResolution(*i));
}
bool changed = false;
newGroups.insert(_blindWildcardMulticastGroup); // always join this
for(std::set<MulticastGroup>::iterator mg(newGroups.begin());mg!=newGroups.end();++mg) {
if (!groups.count(*mg)) {
groups.insert(*mg);
changed = true;
}
}
for(std::set<MulticastGroup>::iterator mg(groups.begin());mg!=groups.end();) {
if (!newGroups.count(*mg)) {
groups.erase(mg++);
changed = true;
} else ++mg;
}
return changed;
}
#endif // __LINUX__
#ifdef __APPLE__
// --------------------------------------------------------------------------
// This source is from:
// http://www.opensource.apple.com/source/Libinfo/Libinfo-406.17/gen.subproj/getifmaddrs.c?txt
// It's here because OSX 10.6 does not have this convenience function.
#define SALIGN (sizeof(uint32_t) - 1)
#define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : \
(SALIGN + 1))
#define MAX_SYSCTL_TRY 5
#define RTA_MASKS (RTA_GATEWAY | RTA_IFP | RTA_IFA)
/* FreeBSD uses NET_RT_IFMALIST and RTM_NEWMADDR from <sys/socket.h> */
/* We can use NET_RT_IFLIST2 and RTM_NEWMADDR2 on Darwin */
//#define DARWIN_COMPAT
//#ifdef DARWIN_COMPAT
#define GIM_SYSCTL_MIB NET_RT_IFLIST2
#define GIM_RTM_ADDR RTM_NEWMADDR2
//#else
//#define GIM_SYSCTL_MIB NET_RT_IFMALIST
//#define GIM_RTM_ADDR RTM_NEWMADDR
//#endif
// Not in 10.6 includes so use our own
struct _intl_ifmaddrs {
struct _intl_ifmaddrs *ifma_next;
struct sockaddr *ifma_name;
struct sockaddr *ifma_addr;
struct sockaddr *ifma_lladdr;
};
static inline int _intl_getifmaddrs(struct _intl_ifmaddrs **pif)
{
int icnt = 1;
int dcnt = 0;
int ntry = 0;
size_t len;
size_t needed;
int mib[6];
int i;
char *buf;
char *data;
char *next;
char *p;
struct ifma_msghdr2 *ifmam;
struct _intl_ifmaddrs *ifa, *ift;
struct rt_msghdr *rtm;
struct sockaddr *sa;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0; /* protocol */
mib[3] = 0; /* wildcard address family */
mib[4] = GIM_SYSCTL_MIB;
mib[5] = 0; /* no flags */
do {
if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
return (-1);
if ((buf = (char *)malloc(needed)) == NULL)
return (-1);
if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
free(buf);
return (-1);
}
free(buf);
buf = NULL;
}
} while (buf == NULL);
for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
switch (rtm->rtm_type) {
case GIM_RTM_ADDR:
ifmam = (struct ifma_msghdr2 *)(void *)rtm;
if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
break;
icnt++;
p = (char *)(ifmam + 1);
for (i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifmam->ifmam_addrs &
(1 << i)) == 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
dcnt += len;
p += len;
}
break;
}
}
data = (char *)malloc(sizeof(struct _intl_ifmaddrs) * icnt + dcnt);
if (data == NULL) {
free(buf);
return (-1);
}
ifa = (struct _intl_ifmaddrs *)(void *)data;
data += sizeof(struct _intl_ifmaddrs) * icnt;
memset(ifa, 0, sizeof(struct _intl_ifmaddrs) * icnt);
ift = ifa;
for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
switch (rtm->rtm_type) {
case GIM_RTM_ADDR:
ifmam = (struct ifma_msghdr2 *)(void *)rtm;
if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
break;
p = (char *)(ifmam + 1);
for (i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifmam->ifmam_addrs &
(1 << i)) == 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
switch (i) {
case RTAX_GATEWAY:
ift->ifma_lladdr =
(struct sockaddr *)(void *)data;
memcpy(data, p, len);
data += len;
break;
case RTAX_IFP:
ift->ifma_name =
(struct sockaddr *)(void *)data;
memcpy(data, p, len);
data += len;
break;
case RTAX_IFA:
ift->ifma_addr =
(struct sockaddr *)(void *)data;
memcpy(data, p, len);
data += len;
break;
default:
data += len;
break;
}
p += len;
}
ift->ifma_next = ift + 1;
ift = ift->ifma_next;
break;
}
}
free(buf);
if (ift > ifa) {
ift--;
ift->ifma_next = NULL;
*pif = ifa;
} else {
*pif = NULL;
free(ifa);
}
return (0);
}
static inline void _intl_freeifmaddrs(struct _intl_ifmaddrs *ifmp)
{
free(ifmp);
}
// --------------------------------------------------------------------------
bool EthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
{
std::set<MulticastGroup> newGroups;
struct _intl_ifmaddrs *ifmap = (struct _intl_ifmaddrs *)0;
if (!_intl_getifmaddrs(&ifmap)) {
struct _intl_ifmaddrs *p = ifmap;
while (p) {
if (p->ifma_addr->sa_family == AF_LINK) {
struct sockaddr_dl *in = (struct sockaddr_dl *)p->ifma_name;
struct sockaddr_dl *la = (struct sockaddr_dl *)p->ifma_addr;
if ((la->sdl_alen == 6)&&(in->sdl_nlen <= sizeof(_dev))&&(!memcmp(_dev,in->sdl_data,in->sdl_nlen)))
newGroups.insert(MulticastGroup(MAC(la->sdl_data + la->sdl_nlen),0));
}
p = p->ifma_next;
}
_intl_freeifmaddrs(ifmap);
}
{
std::set<InetAddress> allIps(ips());
for(std::set<InetAddress>::const_iterator i(allIps.begin());i!=allIps.end();++i)
newGroups.insert(MulticastGroup::deriveMulticastGroupForAddressResolution(*i));
}
bool changed = false;
newGroups.insert(_blindWildcardMulticastGroup); // always join this
for(std::set<MulticastGroup>::iterator mg(newGroups.begin());mg!=newGroups.end();++mg) {
if (!groups.count(*mg)) {
groups.insert(*mg);
changed = true;
}
}
for(std::set<MulticastGroup>::iterator mg(groups.begin());mg!=groups.end();) {
if (!newGroups.count(*mg)) {
groups.erase(mg++);
changed = true;
} else ++mg;
}
return changed;
}
#endif // __APPLE__
void EthernetTap::threadMain()
throw()
{
fd_set readfds,nullfds;
MAC to,from;
int n,nfds,r;
char getBuf[8194];
Buffer<4096> data;
// Wait for a moment after startup -- wait for Network to finish
// constructing itself.
Thread::sleep(500);
FD_ZERO(&readfds);
FD_ZERO(&nullfds);
nfds = (int)std::max(_shutdownSignalPipe[0],_fd) + 1;
r = 0;
for(;;) {
FD_SET(_shutdownSignalPipe[0],&readfds);
FD_SET(_fd,&readfds);
select(nfds,&readfds,&nullfds,&nullfds,(struct timeval *)0);
if (FD_ISSET(_shutdownSignalPipe[0],&readfds)) // writes to shutdown pipe terminate thread
break;
if (FD_ISSET(_fd,&readfds)) {
n = (int)::read(_fd,getBuf + r,sizeof(getBuf) - r);
if (n < 0) {
if ((errno != EINTR)&&(errno != ETIMEDOUT)) {
TRACE("unexpected error reading from tap: %s",strerror(errno));
break;
}
} else {
// Some tap drivers like to send the ethernet frame and the
// payload in two chunks, so handle that by accumulating
// data until we have at least a frame.
r += n;
if (r > 14) {
if (r > ((int)_mtu + 14)) // sanity check for weird TAP behavior on some platforms
r = _mtu + 14;
for(int i=0;i<6;++i)
to.data[i] = (unsigned char)getBuf[i];
for(int i=0;i<6;++i)
from.data[i] = (unsigned char)getBuf[i + 6];
unsigned int etherType = ntohs(((const uint16_t *)getBuf)[6]);
if (etherType != 0x8100) { // VLAN tagged frames are not supported!
data.copyFrom(getBuf + 14,(unsigned int)r - 14);
_handler(_arg,from,to,etherType,data);
}
r = 0;
}
}
}
}
}
bool EthernetTap::deletePersistentTapDevice(const RuntimeEnvironment *_r,const char *pid)
{
return false;
}
int EthernetTap::cleanPersistentTapDevices(const RuntimeEnvironment *_r,const std::set<std::string> &exceptThese,bool alsoRemoveUnassociatedDev)
{
return 0;
}
} // namespace ZeroTier
#endif // __UNIX_LIKE__ //////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
#ifdef __WINDOWS__ ///////////////////////////////////////////////////////////
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <WinSock2.h>
#include <Windows.h>
#include <iphlpapi.h>
#include <ws2ipdef.h>
#include <WS2tcpip.h>
#include <tchar.h>
#include <winreg.h>
#include <wchar.h>
#include <nldef.h>
#include <netioapi.h>
#include "..\windows\TapDriver\tap-windows.h"
namespace ZeroTier {
// Helper function to get an adapter's LUID and index from its GUID. The LUID is
// constant but the index can change, so go ahead and just look them both up by
// the GUID which is constant. (The GUID is the instance ID in the registry.)
static inline std::pair<NET_LUID,NET_IFINDEX> _findAdapterByGuid(const GUID &guid)
throw(std::runtime_error)
{
MIB_IF_TABLE2 *ift = (MIB_IF_TABLE2 *)0;
if (GetIfTable2Ex(MibIfTableRaw,&ift) != NO_ERROR)
throw std::runtime_error("GetIfTable2Ex() failed");
for(ULONG i=0;i<ift->NumEntries;++i) {
if (ift->Table[i].InterfaceGuid == guid) {
std::pair<NET_LUID,NET_IFINDEX> tmp(ift->Table[i].InterfaceLuid,ift->Table[i].InterfaceIndex);
FreeMibTable(ift);
return tmp;
}
}
FreeMibTable(&ift);
throw std::runtime_error("interface not found");
}
static Mutex _systemTapInitLock;
EthernetTap::EthernetTap(
const RuntimeEnvironment *renv,
const char *tag,
const MAC &mac,
unsigned int mtu,
void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
void *arg)
throw(std::runtime_error) :
_mac(mac),
_mtu(mtu),
_r(renv),
_handler(handler),
_arg(arg),
_tap(INVALID_HANDLE_VALUE),
_injectSemaphore(INVALID_HANDLE_VALUE),
_run(true),
_initialized(false)
{
char subkeyName[4096];
char subkeyClass[4096];
char data[4096];
if (mtu > ZT_IF_MTU)
throw std::runtime_error("MTU too large for Windows tap");
#ifdef _WIN64
BOOL is64Bit = TRUE;
const char *devcon = "\\devcon_x64.exe";
const char *tapDriver = "\\tap-windows\\x64\\zttap200.inf";
#else
BOOL is64Bit = FALSE;
IsWow64Process(GetCurrentProcess(),&is64Bit);
const char *devcon = ((is64Bit == TRUE) ? "\\devcon_x64.exe" : "\\devcon_x86.exe");
const char *tapDriver = ((is64Bit == TRUE) ? "\\tap-windows\\x64\\zttap200.inf" : "\\tap-windows\\x86\\zttap200.inf");
#endif
Mutex::Lock _l(_systemTapInitLock); // only one thread may mess with taps at a time, process-wide
HKEY nwAdapters;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}",0,KEY_READ|KEY_WRITE,&nwAdapters) != ERROR_SUCCESS)
throw std::runtime_error("unable to open registry key for network adapter enumeration");
std::set<std::string> existingDeviceInstances;
std::string mySubkeyName;
// Look for the tap instance that corresponds with our interface tag (network ID)
for(DWORD subkeyIndex=0;;++subkeyIndex) {
DWORD type;
DWORD dataLen;
DWORD subkeyNameLen = sizeof(subkeyName);
DWORD subkeyClassLen = sizeof(subkeyClass);
FILETIME lastWriteTime;
if (RegEnumKeyExA(nwAdapters,subkeyIndex,subkeyName,&subkeyNameLen,(DWORD *)0,subkeyClass,&subkeyClassLen,&lastWriteTime) == ERROR_SUCCESS) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"ComponentId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strnicmp(data,"zttap",5)) {
std::string instanceId;
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"NetCfgInstanceId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
instanceId.assign(data,dataLen);
existingDeviceInstances.insert(instanceId);
}
std::string instanceIdPath;
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"DeviceInstanceID",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS)
instanceIdPath.assign(data,dataLen);
if ((_myDeviceInstanceId.length() == 0)&&(instanceId.length() != 0)&&(instanceIdPath.length() != 0)) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"_ZeroTierTapIdentifier",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strcmp(data,tag)) {
_myDeviceInstanceId = instanceId;
_myDeviceInstanceIdPath = instanceIdPath;
mySubkeyName = subkeyName;
break; // found it!
}
}
}
}
}
} else break; // no more subkeys or error occurred enumerating them
}
// If there is no device, try to create one
if (_myDeviceInstanceId.length() == 0) {
// Log devcon output to a file
HANDLE devconLog = CreateFileA((_r->homePath + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if (devconLog == INVALID_HANDLE_VALUE) {
LOG("WARNING: unable to open devcon.log");
} else {
SetFilePointer(devconLog,0,0,FILE_END);
}
// Execute devcon to install an instance of the Microsoft Loopback Adapter
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
SetFilePointer(devconLog,0,0,FILE_END);
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _r->homePath + devcon + "\" install \"" + _r->homePath + tapDriver + "\" zttap200").c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
RegCloseKey(nwAdapters);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
throw std::runtime_error(std::string("unable to find or execute devcon at ")+devcon);
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
// Scan for the new instance by simply looking for taps that weren't
// there originally. The static mutex we lock ensures this can't step
// on its own toes.
for(DWORD subkeyIndex=0;;++subkeyIndex) {
DWORD type;
DWORD dataLen;
DWORD subkeyNameLen = sizeof(subkeyName);
DWORD subkeyClassLen = sizeof(subkeyClass);
FILETIME lastWriteTime;
if (RegEnumKeyExA(nwAdapters,subkeyIndex,subkeyName,&subkeyNameLen,(DWORD *)0,subkeyClass,&subkeyClassLen,&lastWriteTime) == ERROR_SUCCESS) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"ComponentId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strnicmp(data,"zttap",5)) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"NetCfgInstanceId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
if (existingDeviceInstances.count(std::string(data,dataLen)) == 0) {
RegSetKeyValueA(nwAdapters,subkeyName,"_ZeroTierTapIdentifier",REG_SZ,tag,(DWORD)(strlen(tag)+1));
_myDeviceInstanceId.assign(data,dataLen);
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"DeviceInstanceID",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS)
_myDeviceInstanceIdPath.assign(data,dataLen);
mySubkeyName = subkeyName;
// Disable DHCP by default on newly created devices
HKEY tcpIpInterfaces;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\services\\Tcpip\\Parameters\\Interfaces",0,KEY_READ|KEY_WRITE,&tcpIpInterfaces) == ERROR_SUCCESS) {
DWORD enable = 0;
RegSetKeyValueA(tcpIpInterfaces,_myDeviceInstanceId.c_str(),"EnableDHCP",REG_DWORD,&enable,sizeof(enable));
RegCloseKey(tcpIpInterfaces);
}
break; // found it!
}
}
}
}
} else break; // no more keys or error occurred
}
}
if (_myDeviceInstanceId.length() > 0) {
char tmps[4096];
unsigned int tmpsl = Utils::snprintf(tmps,sizeof(tmps),"%.2X-%.2X-%.2X-%.2X-%.2X-%.2X",(unsigned int)mac.data[0],(unsigned int)mac.data[1],(unsigned int)mac.data[2],(unsigned int)mac.data[3],(unsigned int)mac.data[4],(unsigned int)mac.data[5]) + 1;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"NetworkAddress",REG_SZ,tmps,tmpsl);
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"MAC",REG_SZ,tmps,tmpsl);
DWORD tmp = mtu;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"MTU",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
tmp = 0;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"EnableDHCP",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
} else {
RegCloseKey(nwAdapters);
throw std::runtime_error("unable to find or create tap adapter");
}
RegCloseKey(nwAdapters);
// Convert device GUID junk... blech... is there an easier way to do this?
{
char nobraces[128];
const char *nbtmp1 = _myDeviceInstanceId.c_str();
char *nbtmp2 = nobraces;
while (*nbtmp1) {
if ((*nbtmp1 != '{')&&(*nbtmp1 != '}'))
*nbtmp2++ = *nbtmp1;
++nbtmp1;
}
*nbtmp2 = (char)0;
if (UuidFromStringA((RPC_CSTR)nobraces,&_deviceGuid) != RPC_S_OK)
throw std::runtime_error("unable to convert instance ID GUID to native GUID (invalid NetCfgInstanceId in registry?)");
}
// Disable and enable interface to ensure registry settings take effect
{
HANDLE devconLog = CreateFileA((_r->homePath + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if (devconLog != INVALID_HANDLE_VALUE)
SetFilePointer(devconLog,0,0,FILE_END);
{
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _r->homePath + devcon + "\" disable @" + _myDeviceInstanceIdPath).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
RegCloseKey(nwAdapters);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
throw std::runtime_error(std::string("unable to find or execute devcon at ")+devcon);
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
}
{
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _r->homePath + devcon + "\" enable @" + _myDeviceInstanceIdPath).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
RegCloseKey(nwAdapters);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
throw std::runtime_error(std::string("unable to find or execute devcon at ")+devcon);
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
}
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
}
// Open the tap, which is in this weird Windows analog of /dev
char tapPath[4096];
Utils::snprintf(tapPath,sizeof(tapPath),"\\\\.\\Global\\%s.tap",_myDeviceInstanceId.c_str());
_tap = CreateFileA(tapPath,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_SYSTEM|FILE_FLAG_OVERLAPPED,NULL);
if (_tap == INVALID_HANDLE_VALUE)
throw std::runtime_error(std::string("unable to open tap device ")+tapPath);
// Set media status to enabled
uint32_t tmpi = 1;
DWORD bytesReturned = 0;
DeviceIoControl(_tap,TAP_WIN_IOCTL_SET_MEDIA_STATUS,&tmpi,sizeof(tmpi),&tmpi,sizeof(tmpi),&bytesReturned,NULL);
// Initialized overlapped I/O structures and related events
memset(&_tapOvlRead,0,sizeof(_tapOvlRead));
_tapOvlRead.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
memset(&_tapOvlWrite,0,sizeof(_tapOvlWrite));
_tapOvlWrite.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
// Start background thread that actually performs I/O
_injectSemaphore = CreateSemaphore(NULL,0,1,NULL);
_thread = Thread::start(this);
// Certain functions can now work (e.g. ips())
_initialized = true;
}
EthernetTap::~EthernetTap()
{
_run = false;
ReleaseSemaphore(_injectSemaphore,1,NULL);
Thread::join(_thread);
CloseHandle(_tap);
CloseHandle(_tapOvlRead.hEvent);
CloseHandle(_tapOvlWrite.hEvent);
CloseHandle(_injectSemaphore);
#ifdef _WIN64
BOOL is64Bit = TRUE;
const char *devcon = "\\devcon_x64.exe";
#else
BOOL is64Bit = FALSE;
IsWow64Process(GetCurrentProcess(),&is64Bit);
const char *devcon = ((is64Bit == TRUE) ? "\\devcon_x64.exe" : "\\devcon_x86.exe");
#endif
// Disable network device on shutdown
HANDLE devconLog = CreateFileA((_r->homePath + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
SetFilePointer(devconLog,0,0,FILE_END);
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (CreateProcessA(NULL,(LPSTR)(std::string("\"") + _r->homePath + devcon + "\" disable @" + _myDeviceInstanceIdPath).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
}
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
}
void EthernetTap::setDisplayName(const char *dn)
{
if (!_initialized)
return;
HKEY ifp;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,(std::string("SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}\\") + _myDeviceInstanceId).c_str(),0,KEY_READ|KEY_WRITE,&ifp) == ERROR_SUCCESS) {
RegSetKeyValueA(ifp,"Connection","Name",REG_SZ,(LPCVOID)dn,(DWORD)(strlen(dn)+1));
RegCloseKey(ifp);
}
}
bool EthernetTap::addIP(const InetAddress &ip)
{
if (!_initialized)
return false;
if (!ip.netmaskBits()) // sanity check... netmask of 0.0.0.0 is WUT?
return false;
std::set<InetAddress> haveIps(ips());
try {
// Add IP to interface at the netlink level if not already assigned.
if (!haveIps.count(ip)) {
std::pair<NET_LUID,NET_IFINDEX> ifidx = _findAdapterByGuid(_deviceGuid);
MIB_UNICASTIPADDRESS_ROW ipr;
InitializeUnicastIpAddressEntry(&ipr);
if (ip.isV4()) {
ipr.Address.Ipv4.sin_family = AF_INET;
ipr.Address.Ipv4.sin_addr.S_un.S_addr = *((const uint32_t *)ip.rawIpData());
ipr.OnLinkPrefixLength = ip.port();
} else if (ip.isV6()) {
// TODO
} else return false;
ipr.PrefixOrigin = IpPrefixOriginManual;
ipr.SuffixOrigin = IpSuffixOriginManual;
ipr.ValidLifetime = 0xffffffff;
ipr.PreferredLifetime = 0xffffffff;
ipr.InterfaceLuid = ifidx.first;
ipr.InterfaceIndex = ifidx.second;
if (CreateUnicastIpAddressEntry(&ipr) == NO_ERROR) {
haveIps.insert(ip);
} else {
LOG("unable to add IP address %s to interface %s: %d",ip.toString().c_str(),deviceName().c_str(),(int)GetLastError());
return false;
}
}
_syncIpsWithRegistry(haveIps);
} catch (std::exception &exc) {
LOG("unexpected exception adding IP address %s to %s: %s",ip.toString().c_str(),deviceName().c_str(),exc.what());
} catch ( ... ) {
LOG("unexpected exception adding IP address %s to %s: unknown exception",ip.toString().c_str(),deviceName().c_str());
}
return false;
}
bool EthernetTap::removeIP(const InetAddress &ip)
{
if (!_initialized)
return false;
try {
MIB_UNICASTIPADDRESS_TABLE *ipt = (MIB_UNICASTIPADDRESS_TABLE *)0;
std::pair<NET_LUID,NET_IFINDEX> ifidx = _findAdapterByGuid(_deviceGuid);
if (GetUnicastIpAddressTable(AF_UNSPEC,&ipt) == NO_ERROR) {
for(DWORD i=0;i<ipt->NumEntries;++i) {
if ((ipt->Table[i].InterfaceLuid.Value == ifidx.first.Value)&&(ipt->Table[i].InterfaceIndex == ifidx.second)) {
InetAddress addr;
switch(ipt->Table[i].Address.si_family) {
case AF_INET:
addr.set(&(ipt->Table[i].Address.Ipv4.sin_addr.S_un.S_addr),4,ipt->Table[i].OnLinkPrefixLength);
break;
case AF_INET6:
addr.set(ipt->Table[i].Address.Ipv6.sin6_addr.u.Byte,16,ipt->Table[i].OnLinkPrefixLength);
if (addr.isLinkLocal())
continue; // can't remove link-local IPv6 addresses
break;
}
if (addr == ip) {
DeleteUnicastIpAddressEntry(&(ipt->Table[i]));
FreeMibTable(ipt);
_syncIpsWithRegistry(ips());
return true;
}
}
}
FreeMibTable((PVOID)ipt);
}
} catch (std::exception &exc) {
LOG("unexpected exception removing IP address %s from %s: %s",ip.toString().c_str(),deviceName().c_str(),exc.what());
} catch ( ... ) {
LOG("unexpected exception removing IP address %s from %s: unknown exception",ip.toString().c_str(),deviceName().c_str());
}
return false;
}
std::set<InetAddress> EthernetTap::ips() const
{
static const InetAddress linkLocalLoopback("fe80::1",64); // what is this and why does Windows assign it?
std::set<InetAddress> addrs;
if (!_initialized)
return addrs;
try {
MIB_UNICASTIPADDRESS_TABLE *ipt = (MIB_UNICASTIPADDRESS_TABLE *)0;
std::pair<NET_LUID,NET_IFINDEX> ifidx = _findAdapterByGuid(_deviceGuid);
if (GetUnicastIpAddressTable(AF_UNSPEC,&ipt) == NO_ERROR) {
for(DWORD i=0;i<ipt->NumEntries;++i) {
if ((ipt->Table[i].InterfaceLuid.Value == ifidx.first.Value)&&(ipt->Table[i].InterfaceIndex == ifidx.second)) {
switch(ipt->Table[i].Address.si_family) {
case AF_INET: {
InetAddress ip(&(ipt->Table[i].Address.Ipv4.sin_addr.S_un.S_addr),4,ipt->Table[i].OnLinkPrefixLength);
if (ip != InetAddress::LO4)
addrs.insert(ip);
} break;
case AF_INET6: {
InetAddress ip(ipt->Table[i].Address.Ipv6.sin6_addr.u.Byte,16,ipt->Table[i].OnLinkPrefixLength);
if ((ip != linkLocalLoopback)&&(ip != InetAddress::LO6))
addrs.insert(ip);
} break;
}
}
}
FreeMibTable(ipt);
}
} catch ( ... ) {}
return addrs;
}
void EthernetTap::put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len)
{
if (!_initialized)
return;
if (len > (ZT_IF_MTU))
return; // sanity check
{
Mutex::Lock _l(_injectPending_m);
_injectPending.push( std::pair<Array<char,ZT_IF_MTU + 32>,unsigned int>(Array<char,ZT_IF_MTU + 32>(),len + 14) );
char *d = _injectPending.back().first.data;
memcpy(d,to.data,6);
memcpy(d + 6,from.data,6);
d[12] = (char)((etherType >> 8) & 0xff);
d[13] = (char)(etherType & 0xff);
memcpy(d + 14,data,len);
}
ReleaseSemaphore(_injectSemaphore,1,NULL);
}
std::string EthernetTap::deviceName() const
{
return _myDeviceInstanceId;
}
std::string EthernetTap::persistentId() const
{
return _myDeviceInstanceIdPath;
}
bool EthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
{
if (!_initialized)
return false;
std::set<MulticastGroup> newGroups;
// Ensure that groups are added for each IP... this handles the MAC:ADI
// groups that are created from IPv4 addresses. Some of these may end
// up being duplicates of what the IOCTL returns but that's okay since
// the set<> will filter that.
std::set<InetAddress> ipaddrs(ips());
for(std::set<InetAddress>::const_iterator i(ipaddrs.begin());i!=ipaddrs.end();++i)
newGroups.insert(MulticastGroup::deriveMulticastGroupForAddressResolution(*i));
// The ZT1 tap driver supports an IOCTL to get multicast memberships at the L2
// level... something Windows does not seem to expose ordinarily. This lets
// pretty much anything work... IPv4, IPv6, IPX, oldskool Netbios, who knows...
unsigned char mcastbuf[TAP_WIN_IOCTL_GET_MULTICAST_MEMBERSHIPS_OUTPUT_BUF_SIZE];
DWORD bytesReturned = 0;
if (DeviceIoControl(_tap,TAP_WIN_IOCTL_GET_MULTICAST_MEMBERSHIPS,(LPVOID)0,0,(LPVOID)mcastbuf,sizeof(mcastbuf),&bytesReturned,NULL)) {
MAC mac;
DWORD i = 0;
while ((i + 6) <= bytesReturned) {
mac.data[0] = mcastbuf[i++];
mac.data[1] = mcastbuf[i++];
mac.data[2] = mcastbuf[i++];
mac.data[3] = mcastbuf[i++];
mac.data[4] = mcastbuf[i++];
mac.data[5] = mcastbuf[i++];
if (mac.isMulticast()) {
// exclude the nulls that may be returned or any other junk Windows puts in there
newGroups.insert(MulticastGroup(mac,0));
}
}
}
newGroups.insert(_blindWildcardMulticastGroup); // always join this
bool changed = false;
for(std::set<MulticastGroup>::iterator mg(newGroups.begin());mg!=newGroups.end();++mg) {
if (!groups.count(*mg)) {
groups.insert(*mg);
changed = true;
}
}
for(std::set<MulticastGroup>::iterator mg(groups.begin());mg!=groups.end();) {
if (!newGroups.count(*mg)) {
groups.erase(mg++);
changed = true;
} else ++mg;
}
return changed;
}
void EthernetTap::threadMain()
throw()
{
HANDLE wait4[3];
wait4[0] = _injectSemaphore;
wait4[1] = _tapOvlRead.hEvent;
wait4[2] = _tapOvlWrite.hEvent; // only included if writeInProgress is true
ReadFile(_tap,_tapReadBuf,sizeof(_tapReadBuf),NULL,&_tapOvlRead);
bool writeInProgress = false;
for(;;) {
if (!_run) break;
DWORD r = WaitForMultipleObjectsEx(writeInProgress ? 3 : 2,wait4,FALSE,INFINITE,TRUE);
if (!_run) break;
if (HasOverlappedIoCompleted(&_tapOvlRead)) {
DWORD bytesRead = 0;
if (GetOverlappedResult(_tap,&_tapOvlRead,&bytesRead,FALSE)) {
if (bytesRead > 14) {
MAC to(_tapReadBuf);
MAC from(_tapReadBuf + 6);
unsigned int etherType = Utils::ntoh(*((const uint16_t *)(_tapReadBuf + 12)));
Buffer<4096> tmp(_tapReadBuf + 14,bytesRead - 14);
_handler(_arg,from,to,etherType,tmp);
}
}
ReadFile(_tap,_tapReadBuf,sizeof(_tapReadBuf),NULL,&_tapOvlRead);
}
if (writeInProgress) {
if (HasOverlappedIoCompleted(&_tapOvlWrite)) {
writeInProgress = false;
_injectPending_m.lock();
_injectPending.pop();
} else continue; // still writing, so skip code below and wait
} else _injectPending_m.lock();
if (!_injectPending.empty()) {
WriteFile(_tap,_injectPending.front().first.data,_injectPending.front().second,NULL,&_tapOvlWrite);
writeInProgress = true;
}
_injectPending_m.unlock();
}
CancelIo(_tap);
}
bool EthernetTap::deletePersistentTapDevice(const RuntimeEnvironment *_r,const char *pid)
{
#ifdef _WIN64
BOOL is64Bit = TRUE;
const char *devcon = "\\devcon_x64.exe";
#else
BOOL is64Bit = FALSE;
IsWow64Process(GetCurrentProcess(),&is64Bit);
const char *devcon = ((is64Bit == TRUE) ? "\\devcon_x64.exe" : "\\devcon_x86.exe");
#endif
Mutex::Lock _l(_systemTapInitLock); // only one thread may mess with taps at a time, process-wide
HANDLE devconLog = CreateFileA((_r->homePath + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
SetFilePointer(devconLog,0,0,FILE_END);
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (CreateProcessA(NULL,(LPSTR)(std::string("\"") + _r->homePath + devcon + "\" remove @" + pid).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return true;
}
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return false;
}
int EthernetTap::cleanPersistentTapDevices(const RuntimeEnvironment *_r,const std::set<std::string> &exceptThese,bool alsoRemoveUnassociatedDevices)
{
char subkeyName[4096];
char subkeyClass[4096];
char data[4096];
std::set<std::string> instanceIdPathsToRemove;
{
Mutex::Lock _l(_systemTapInitLock); // only one thread may mess with taps at a time, process-wide
HKEY nwAdapters;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}",0,KEY_READ|KEY_WRITE,&nwAdapters) != ERROR_SUCCESS)
return -1;
for(DWORD subkeyIndex=0;;++subkeyIndex) {
DWORD type;
DWORD dataLen;
DWORD subkeyNameLen = sizeof(subkeyName);
DWORD subkeyClassLen = sizeof(subkeyClass);
FILETIME lastWriteTime;
if (RegEnumKeyExA(nwAdapters,subkeyIndex,subkeyName,&subkeyNameLen,(DWORD *)0,subkeyClass,&subkeyClassLen,&lastWriteTime) == ERROR_SUCCESS) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"ComponentId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strnicmp(data,"zttap",5)) {
std::string instanceIdPath;
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"DeviceInstanceID",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS)
instanceIdPath.assign(data,dataLen);
if (instanceIdPath.length() != 0) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"_ZeroTierTapIdentifier",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
if (dataLen <= 0) {
if (alsoRemoveUnassociatedDevices)
instanceIdPathsToRemove.insert(instanceIdPath);
} else {
if (!exceptThese.count(std::string(data,dataLen)))
instanceIdPathsToRemove.insert(instanceIdPath);
}
} else if (alsoRemoveUnassociatedDevices)
instanceIdPathsToRemove.insert(instanceIdPath);
}
}
}
} else break; // end of list or failure
}
RegCloseKey(nwAdapters);
}
int removed = 0;
for(std::set<std::string>::iterator iidp(instanceIdPathsToRemove.begin());iidp!=instanceIdPathsToRemove.end();++iidp) {
if (deletePersistentTapDevice(_r,iidp->c_str()))
++removed;
}
return removed;
}
void EthernetTap::_syncIpsWithRegistry(const std::set<InetAddress> &haveIps)
{
// Update registry to contain all non-link-local IPs for this interface
std::string regMultiIps,regMultiNetmasks;
for(std::set<InetAddress>::const_iterator i(haveIps.begin());i!=haveIps.end();++i) {
if (!i->isLinkLocal()) {
regMultiIps.append(i->toIpString());
regMultiIps.push_back((char)0);
regMultiNetmasks.append(i->netmask().toIpString());
regMultiNetmasks.push_back((char)0);
}
}
HKEY tcpIpInterfaces;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\services\\Tcpip\\Parameters\\Interfaces",0,KEY_READ|KEY_WRITE,&tcpIpInterfaces) == ERROR_SUCCESS) {
if (regMultiIps.length()) {
regMultiIps.push_back((char)0);
regMultiNetmasks.push_back((char)0);
RegSetKeyValueA(tcpIpInterfaces,_myDeviceInstanceId.c_str(),"IPAddress",REG_MULTI_SZ,regMultiIps.data(),(DWORD)regMultiIps.length());
RegSetKeyValueA(tcpIpInterfaces,_myDeviceInstanceId.c_str(),"SubnetMask",REG_MULTI_SZ,regMultiNetmasks.data(),(DWORD)regMultiNetmasks.length());
} else {
RegDeleteKeyValueA(tcpIpInterfaces,_myDeviceInstanceId.c_str(),"IPAddress");
RegDeleteKeyValueA(tcpIpInterfaces,_myDeviceInstanceId.c_str(),"SubnetMask");
}
}
RegCloseKey(tcpIpInterfaces);
}
} // namespace ZeroTier
#endif // __WINDOWS__ ////////////////////////////////////////////////////////