didyouexpectthat_zerotierone/attic/OSXEthernetTap.cpp.pcap-with-bridge-test
2016-11-01 16:45:16 -07:00

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/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2015 ZeroTier, Inc.
*
* 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 <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/route.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <netinet6/in6_var.h>
#include <netinet/in_var.h>
#include <netinet/icmp6.h>
#include <pcap/pcap.h>
// OSX compile fix... in6_var defines this in a struct which namespaces it for C++ ... why?!?
struct prf_ra {
u_char onlink : 1;
u_char autonomous : 1;
u_char reserved : 6;
} prf_ra;
#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
#ifndef ETH_ALEN
#define ETH_ALEN 6
#endif
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
// 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);
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include "../node/Constants.hpp"
#include "../node/Utils.hpp"
#include "../node/Mutex.hpp"
#include "../node/Dictionary.hpp"
#include "OSUtils.hpp"
#include "OSXEthernetTap.hpp"
// ff:ff:ff:ff:ff:ff with no ADI
static const ZeroTier::MulticastGroup _blindWildcardMulticastGroup(ZeroTier::MAC(0xff),0);
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;
}
namespace ZeroTier {
static std::set<std::string> globalDeviceNames;
static Mutex globalTapCreateLock;
OSXEthernetTap::OSXEthernetTap(
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 *data,unsigned int len),
void *arg) :
_handler(handler),
_arg(arg),
_pcap((void *)0),
_nwid(nwid),
_mac(mac),
_homePath(homePath),
_mtu(mtu),
_metric(metric),
_enabled(true)
{
char errbuf[PCAP_ERRBUF_SIZE];
char devname[64],ethaddr[64],mtustr[32],metstr[32],nwids[32];
Utils::snprintf(nwids,sizeof(nwids),"%.16llx",nwid);
if (mtu > 2800)
throw std::runtime_error("max tap MTU is 2800");
Mutex::Lock _gl(globalTapCreateLock);
std::string desiredDevice;
Dictionary devmap;
{
std::string devmapbuf;
if (OSUtils::readFile((_homePath + ZT_PATH_SEPARATOR_S + "devicemap").c_str(),devmapbuf)) {
devmap.fromString(devmapbuf);
desiredDevice = devmap.get(nwids,"");
}
}
if ((desiredDevice.length() >= 9)&&(desiredDevice.substr(0,6) == "bridge")) {
// length() >= 9 matches bridge### or bridge####
_dev = desiredDevice;
} else {
if (globalDeviceNames.size() >= (10000 - 128)) // sanity check... this would be nuts
throw std::runtime_error("too many devices!");
unsigned int pseudoBridgeNo = (unsigned int)((nwid ^ (nwid >> 32)) % (10000 - 128)) + 128; // range: bridge128 to bridge9999
sprintf(devname,"bridge%u",pseudoBridgeNo);
while (globalDeviceNames.count(std::string(devname)) > 0) {
++pseudoBridgeNo;
if (pseudoBridgeNo > 9999)
pseudoBridgeNo = 64;
sprintf(devname,"bridge%u",pseudoBridgeNo);
}
_dev = devname;
}
// Configure MAC address and MTU, bring interface up
long cpid = (long)vfork();
if (cpid == 0) {
::execl("/sbin/ifconfig","/sbin/ifconfig",_dev.c_str(),"create",(const char *)0);
::_exit(-1);
} else if (cpid > 0) {
int exitcode = -1;
::waitpid(cpid,&exitcode,0);
if (exitcode != 0)
throw std::runtime_error("ifconfig failure setting link-layer address and activating tap interface");
} else throw std::runtime_error("unable to fork()");
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);
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 != 0)
throw std::runtime_error("ifconfig failure setting link-layer address and activating tap interface");
} else throw std::runtime_error("unable to fork()");
_setIpv6Stuff(_dev.c_str(),true,false);
_pcap = (void *)pcap_create(_dev.c_str(),errbuf);
if (!_pcap) {
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);
}
throw std::runtime_error((std::string("pcap_create() on new bridge device failed: ") + errbuf).c_str());
}
pcap_set_promisc(reinterpret_cast<pcap_t *>(_pcap),1);
pcap_set_timeout(reinterpret_cast<pcap_t *>(_pcap),120000);
pcap_set_immediate_mode(reinterpret_cast<pcap_t *>(_pcap),1);
if (pcap_set_buffer_size(reinterpret_cast<pcap_t *>(_pcap),1024 * 1024 * 16) != 0) // 16MB
fprintf(stderr,"WARNING: pcap_set_buffer_size() failed!\n");
if (pcap_set_snaplen(reinterpret_cast<pcap_t *>(_pcap),4096) != 0)
fprintf(stderr,"WARNING: pcap_set_snaplen() failed!\n");
if (pcap_activate(reinterpret_cast<pcap_t *>(_pcap)) != 0) {
pcap_close(reinterpret_cast<pcap_t *>(_pcap));
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);
}
throw std::runtime_error("pcap_activate() on new bridge device failed.");
}
globalDeviceNames.insert(_dev);
devmap[nwids] = _dev;
OSUtils::writeFile((_homePath + ZT_PATH_SEPARATOR_S + "devicemap").c_str(),devmap.toString());
_thread = Thread::start(this);
}
OSXEthernetTap::~OSXEthernetTap()
{
_enabled = false;
Mutex::Lock _gl(globalTapCreateLock);
globalDeviceNames.erase(_dev);
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);
if (exitcode == 0) {
// Destroying the interface nukes pcap and terminates the thread.
Thread::join(_thread);
}
}
pcap_close(reinterpret_cast<pcap_t *>(_pcap));
}
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 OSXEthernetTap::addIp(const InetAddress &ip)
{
if (!ip)
return false;
std::vector<InetAddress> allIps(ips());
if (std::binary_search(allIps.begin(),allIps.end(),ip))
return true;
// 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);
} // else return false...
return false;
}
bool OSXEthernetTap::removeIp(const InetAddress &ip)
{
if (!ip)
return true;
std::vector<InetAddress> allIps(ips());
if (!std::binary_search(allIps.begin(),allIps.end(),ip)) {
if (___removeIp(_dev,ip))
return true;
}
return false;
}
std::vector<InetAddress> OSXEthernetTap::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 OSXEthernetTap::put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len)
{
char putBuf[4096];
if ((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;
int r = pcap_inject(reinterpret_cast<pcap_t *>(_pcap),putBuf,len);
if (r <= 0) {
printf("%s: pcap_inject() failed\n",_dev.c_str());
return;
}
printf("%s: inject %s -> %s etherType==%u len=%u r==%d\n",_dev.c_str(),from.toString().c_str(),to.toString().c_str(),etherType,len,r);
}
}
std::string OSXEthernetTap::deviceName() const
{
return _dev;
}
void OSXEthernetTap::setFriendlyName(const char *friendlyName)
{
}
void OSXEthernetTap::scanMulticastGroups(std::vector<MulticastGroup> &added,std::vector<MulticastGroup> &removed)
{
std::vector<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 <= _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;
}
_intl_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);
}
static void _pcapHandler(u_char *ptr,const struct pcap_pkthdr *hdr,const u_char *data)
{
OSXEthernetTap *tap = reinterpret_cast<OSXEthernetTap *>(ptr);
if (hdr->caplen > 14) {
MAC to(data,6);
MAC from(data + 6,6);
if (from == tap->_mac) {
unsigned int etherType = ntohs(((const uint16_t *)data)[6]);
printf("%s: %s -> %s etherType==%u len==%u\n",tap->_dev.c_str(),from.toString().c_str(),to.toString().c_str(),etherType,(unsigned int)hdr->caplen);
// TODO: VLAN support
tap->_handler(tap->_arg,tap->_nwid,from,to,etherType,0,(const void *)(data + 14),hdr->len - 14);
}
}
}
void OSXEthernetTap::threadMain()
throw()
{
pcap_loop(reinterpret_cast<pcap_t *>(_pcap),-1,&_pcapHandler,reinterpret_cast<u_char *>(this));
}
} // namespace ZeroTier