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author | Daniel Skowroński <daniel@dsinf.net> | 2016-12-25 22:54:27 +0100 |
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committer | Daniel Skowroński <daniel@dsinf.net> | 2016-12-25 22:54:27 +0100 |
commit | f09eedbd7adee2a804978182c1f9fdc2a1ad1d6a (patch) | |
tree | fb7e589b885435c76ff4b9fc44dbbd1c2fec9443 /osdep/NetBSDEthernetTap.cpp | |
parent | 546e8a3b44cff7dc3525a672bfe9806d3ee6144e (diff) | |
download | infinitytier-f09eedbd7adee2a804978182c1f9fdc2a1ad1d6a.tar.gz infinitytier-f09eedbd7adee2a804978182c1f9fdc2a1ad1d6a.zip |
make it compilable
Diffstat (limited to 'osdep/NetBSDEthernetTap.cpp')
-rw-r--r-- | osdep/NetBSDEthernetTap.cpp | 464 |
1 files changed, 464 insertions, 0 deletions
diff --git a/osdep/NetBSDEthernetTap.cpp b/osdep/NetBSDEthernetTap.cpp new file mode 100644 index 00000000..109a2a34 --- /dev/null +++ b/osdep/NetBSDEthernetTap.cpp @@ -0,0 +1,464 @@ +/* + * ZeroTier One - Network Virtualization Everywhere + * Copyright (C) 2011-2016 ZeroTier, Inc. https://www.zerotier.com/ + * + * 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/>. + */ + +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> + +#include <unistd.h> +#include <signal.h> + +#include <fcntl.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <sys/wait.h> +#include <sys/select.h> +#include <sys/cdefs.h> +#include <sys/uio.h> +#include <sys/param.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <net/if.h> +#include <ifaddrs.h> +#include <net/if_arp.h> +#include <net/if_dl.h> +#include <net/if_media.h> +#include <net/route.h> + +#include <sys/sysctl.h> + +#include "freebsd_getifmaddrs.h" + +#include <string> +#include <map> +#include <set> +#include <algorithm> +#include <utility> + +#include "../node/Constants.hpp" +#include "../node/Utils.hpp" +#include "../node/Mutex.hpp" +#include "OSUtils.hpp" +#include "NetBSDEthernetTap.hpp" + +#define ZT_BASE32_CHARS "0123456789abcdefghijklmnopqrstuv" + +// ff:ff:ff:ff:ff:ff with no ADI +static const ZeroTier::MulticastGroup _blindWildcardMulticastGroup(ZeroTier::MAC(0xff),0); + +namespace ZeroTier { + +NetBSDEthernetTap::NetBSDEthernetTap( + const char *homePath, + const MAC &mac, + unsigned int mtu, + unsigned int metric, + uint64_t nwid, + const char *friendlyName, + void (*handler)(void *,uint64_t,const MAC &,const MAC &,unsigned int,unsigned int,const void *,unsigned int), + void *arg) : + _handler(handler), + _arg(arg), + _nwid(nwid), + _mtu(mtu), + _metric(metric), + _fd(0), + _enabled(true) +{ + static Mutex globalTapCreateLock; + char devpath[64],ethaddr[64],mtustr[32],metstr[32],tmpdevname[32]; + struct stat stattmp; + + // On FreeBSD at least we can rename, so use nwid to generate a deterministic unique zt#### name using base32 + // As a result we don't use desiredDevice + _dev = "zt"; + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 60) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 55) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 50) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 45) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 40) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 35) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 30) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 25) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 20) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 15) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 10) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)((nwid >> 5) & 0x1f)]); + _dev.push_back(ZT_BASE32_CHARS[(unsigned long)(nwid & 0x1f)]); + + Mutex::Lock _gl(globalTapCreateLock); + + if (mtu > 2800) + throw std::runtime_error("max tap MTU is 2800"); + + // On BSD we create taps and they can have high numbers, so use ones starting + // at 9993 to not conflict with other stuff. Then we rename it to zt<base32 of nwid> + std::vector<std::string> devFiles(OSUtils::listDirectory("/dev")); + for(int i=9993;i<(9993+128);++i) { + Utils::snprintf(tmpdevname,sizeof(tmpdevname),"tap%d",i); + Utils::snprintf(devpath,sizeof(devpath),"/dev/%s",tmpdevname); + if (std::find(devFiles.begin(),devFiles.end(),std::string(tmpdevname)) == devFiles.end()) { + long cpid = (long)vfork(); + if (cpid == 0) { + ::execl("/sbin/ifconfig","/sbin/ifconfig",tmpdevname,"create",(const char *)0); + ::_exit(-1); + } else if (cpid > 0) { + int exitcode = -1; + ::waitpid(cpid,&exitcode,0); + } else throw std::runtime_error("fork() failed"); + + if (!stat(devpath,&stattmp)) { + cpid = (long)vfork(); + if (cpid == 0) { + ::execl("/sbin/ifconfig","/sbin/ifconfig",tmpdevname,"name",_dev.c_str(),(const char *)0); + ::_exit(-1); + } else if (cpid > 0) { + int exitcode = -1; + ::waitpid(cpid,&exitcode,0); + if (exitcode) + throw std::runtime_error("ifconfig rename operation failed"); + } else throw std::runtime_error("fork() failed"); + + _fd = ::open(devpath,O_RDWR); + if (_fd > 0) + break; + else throw std::runtime_error("unable to open created tap device"); + } else { + throw std::runtime_error("cannot find /dev node for newly created tap device"); + } + } + } + + 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"); + } + + // 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); + Utils::snprintf(metstr,sizeof(metstr),"%u",_metric); + long cpid = (long)vfork(); + if (cpid == 0) { + ::execl("/sbin/ifconfig","/sbin/ifconfig",_dev.c_str(),"lladdr",ethaddr,"mtu",mtustr,"metric",metstr,"up",(const char *)0); + ::_exit(-1); + } else if (cpid > 0) { + 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"); + } + } + + // Set close-on-exec so that devices cannot persist if we fork/exec for update + fcntl(_fd,F_SETFD,fcntl(_fd,F_GETFD) | FD_CLOEXEC); + + ::pipe(_shutdownSignalPipe); + + _thread = Thread::start(this); +} + +NetBSDEthernetTap::~NetBSDEthernetTap() +{ + ::write(_shutdownSignalPipe[1],"\0",1); // causes thread to exit + Thread::join(_thread); + ::close(_fd); + ::close(_shutdownSignalPipe[0]); + ::close(_shutdownSignalPipe[1]); + + long cpid = (long)vfork(); + if (cpid == 0) { + ::execl("/sbin/ifconfig","/sbin/ifconfig",_dev.c_str(),"destroy",(const char *)0); + ::_exit(-1); + } else if (cpid > 0) { + int exitcode = -1; + ::waitpid(cpid,&exitcode,0); + } +} + +void NetBSDEthernetTap::setEnabled(bool en) +{ + _enabled = en; +} + +bool NetBSDEthernetTap::enabled() const +{ + return _enabled; +} + +static bool ___removeIp(const std::string &_dev,const InetAddress &ip) +{ + long cpid = (long)vfork(); + if (cpid == 0) { + execl("/sbin/ifconfig","/sbin/ifconfig",_dev.c_str(),"inet",ip.toIpString().c_str(),"-alias",(const char *)0); + _exit(-1); + } else if (cpid > 0) { + int exitcode = -1; + waitpid(cpid,&exitcode,0); + return (exitcode == 0); + } + return false; // never reached, make compiler shut up about return value +} + +bool NetBSDEthernetTap::addIp(const InetAddress &ip) +{ + if (!ip) + return false; + + std::vector<InetAddress> allIps(ips()); + if (std::find(allIps.begin(),allIps.end(),ip) != allIps.end()) + return true; // IP/netmask already assigned + + // Remove and reconfigure if address is the same but netmask is different + for(std::vector<InetAddress>::iterator i(allIps.begin());i!=allIps.end();++i) { + if ((i->ipsEqual(ip))&&(i->netmaskBits() != ip.netmaskBits())) { + if (___removeIp(_dev,*i)) + break; + } + } + + long cpid = (long)vfork(); + if (cpid == 0) { + ::execl("/sbin/ifconfig","/sbin/ifconfig",_dev.c_str(),ip.isV4() ? "inet" : "inet6",ip.toString().c_str(),"alias",(const char *)0); + ::_exit(-1); + } else if (cpid > 0) { + int exitcode = -1; + ::waitpid(cpid,&exitcode,0); + return (exitcode == 0); + } + return false; +} + +bool NetBSDEthernetTap::removeIp(const InetAddress &ip) +{ + if (!ip) + return false; + std::vector<InetAddress> allIps(ips()); + if (std::find(allIps.begin(),allIps.end(),ip) != allIps.end()) { + if (___removeIp(_dev,ip)) + return true; + } + return false; +} + +std::vector<InetAddress> NetBSDEthernetTap::ips() const +{ + struct ifaddrs *ifa = (struct ifaddrs *)0; + if (getifaddrs(&ifa)) + return std::vector<InetAddress>(); + + std::vector<InetAddress> r; + + struct ifaddrs *p = ifa; + while (p) { + if ((!strcmp(p->ifa_name,_dev.c_str()))&&(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.push_back(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.push_back(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); + + std::sort(r.begin(),r.end()); + std::unique(r.begin(),r.end()); + + return r; +} + +void NetBSDEthernetTap::put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len) +{ + char putBuf[4096]; + if ((_fd > 0)&&(len <= _mtu)&&(_enabled)) { + to.copyTo(putBuf,6); + from.copyTo(putBuf + 6,6); + *((uint16_t *)(putBuf + 12)) = htons((uint16_t)etherType); + memcpy(putBuf + 14,data,len); + len += 14; + ::write(_fd,putBuf,len); + } +} + +std::string NetBSDEthernetTap::deviceName() const +{ + return _dev; +} + +void NetBSDEthernetTap::setFriendlyName(const char *friendlyName) +{ +} + +void NetBSDEthernetTap::scanMulticastGroups(std::vector<MulticastGroup> &added,std::vector<MulticastGroup> &removed) +{ + std::vector<MulticastGroup> newGroups; + + struct ifmaddrs *ifmap = (struct ifmaddrs *)0; + if (!getifmaddrs(&ifmap)) { + struct 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 <= _dev.length())&&(!memcmp(_dev.data(),in->sdl_data,in->sdl_nlen))) + newGroups.push_back(MulticastGroup(MAC(la->sdl_data + la->sdl_nlen,6),0)); + } + p = p->ifma_next; + } + freeifmaddrs(ifmap); + } + + std::vector<InetAddress> allIps(ips()); + for(std::vector<InetAddress>::iterator ip(allIps.begin());ip!=allIps.end();++ip) + newGroups.push_back(MulticastGroup::deriveMulticastGroupForAddressResolution(*ip)); + + std::sort(newGroups.begin(),newGroups.end()); + std::unique(newGroups.begin(),newGroups.end()); + + for(std::vector<MulticastGroup>::iterator m(newGroups.begin());m!=newGroups.end();++m) { + if (!std::binary_search(_multicastGroups.begin(),_multicastGroups.end(),*m)) + added.push_back(*m); + } + for(std::vector<MulticastGroup>::iterator m(_multicastGroups.begin());m!=_multicastGroups.end();++m) { + if (!std::binary_search(newGroups.begin(),newGroups.end(),*m)) + removed.push_back(*m); + } + + _multicastGroups.swap(newGroups); +} + +/* +bool NetBSDEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups) +{ + std::set<MulticastGroup> newGroups; + struct ifmaddrs *ifmap = (struct ifmaddrs *)0; + if (!getifmaddrs(&ifmap)) { + struct 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 <= _dev.length())&&(!memcmp(_dev.data(),in->sdl_data,in->sdl_nlen))) + newGroups.insert(MulticastGroup(MAC(la->sdl_data + la->sdl_nlen,6),0)); + } + p = p->ifma_next; + } + 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; + + 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))&&(*mg != _blindWildcardMulticastGroup)) { + groups.erase(mg++); + changed = true; + } else ++mg; + } + + return changed; +} +*/ + +void NetBSDEthernetTap::threadMain() + throw() +{ + fd_set readfds,nullfds; + MAC to,from; + int n,nfds,r; + char getBuf[8194]; + + // 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)) + 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; + + if (_enabled) { + to.setTo(getBuf,6); + from.setTo(getBuf + 6,6); + unsigned int etherType = ntohs(((const uint16_t *)getBuf)[6]); + // TODO: VLAN support + _handler(_arg,_nwid,from,to,etherType,0,(const void *)(getBuf + 14),r - 14); + } + + r = 0; + } + } + } + } +} + +} // namespace ZeroTier |