diff --git a/src/client.py b/src/client.py index f919b37..9fde1a7 100644 --- a/src/client.py +++ b/src/client.py @@ -12,8 +12,6 @@ import ssyslog import sys from ssnet import SockWrapper, Handler, Proxy, Mux, MuxWrapper from helpers import log, debug1, debug2, debug3, Fatal, islocal -from fcntl import ioctl -from ctypes import c_char, c_uint8, c_uint16, c_uint32, Union, Structure, sizeof, addressof, memmove recvmsg = None try: @@ -186,79 +184,22 @@ def daemon_cleanup(): else: raise - -class pf_state_xport(Union): - _fields_ = [("port", c_uint16), - ("call_id", c_uint16), - ("spi", c_uint32)] - -class pf_addr(Structure): - class _pfa(Union): - _fields_ = [("v4", c_uint32), # struct in_addr - ("v6", c_uint32 * 4), # struct in6_addr - ("addr8", c_uint8 * 16), - ("addr16", c_uint16 * 8), - ("addr32", c_uint32 * 4)] - - _fields_ = [("pfa", _pfa)] - _anonymous_ = ("pfa",) - -class pfioc_natlook(Structure): - _fields_ = [("saddr", pf_addr), - ("daddr", pf_addr), - ("rsaddr", pf_addr), - ("rdaddr", pf_addr), - ("sxport", pf_state_xport), - ("dxport", pf_state_xport), - ("rsxport", pf_state_xport), - ("rdxport", pf_state_xport), - ("af", c_uint8), # sa_family_t - ("proto", c_uint8), - ("proto_variant", c_uint8), - ("direction", c_uint8)] - -DIOCNATLOOK = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_natlook) & 0x1fff) << 16) | ((ord('D')) << 8) | (23)) -PF_OUT = 2 - -_pf_fd = None +pf_command_file = None def pf_dst(sock): - global _pf_fd - try: - peer = sock.getpeername() - proxy = sock.getsockname() + peer = sock.getpeername() + proxy = sock.getsockname() - pnl = pfioc_natlook() - pnl.proto = socket.IPPROTO_TCP - pnl.direction = PF_OUT - if sock.family == socket.AF_INET: - pnl.af = socket.AF_INET - memmove(addressof(pnl.saddr), socket.inet_pton(socket.AF_INET, peer[0]), 4) - pnl.sxport.port = socket.htons(peer[1]) - memmove(addressof(pnl.daddr), socket.inet_pton(socket.AF_INET, proxy[0]), 4) - pnl.dxport.port = socket.htons(proxy[1]) - elif sock.family == socket.AF_INET6: - pnl.af = socket.AF_INET6 - memmove(addressof(pnl.saddr), socket.inet_pton(socket.AF_INET6, peer[0]), 16) - pnl.sxport.port = socket.htons(peer[1]) - memmove(addressof(pnl.daddr), socket.inet_pton(socket.AF_INET6, proxy[0]), 16) - pnl.dxport.port = socket.htons(proxy[1]) - - if _pf_fd == None: - _pf_fd = open('/dev/pf', 'r') - - ioctl(_pf_fd, DIOCNATLOOK, (c_char * sizeof(pnl)).from_address(addressof(pnl))) - - if pnl.af == socket.AF_INET: - ip = socket.inet_ntop(socket.AF_INET, (c_char * 4).from_address(addressof(pnl.rdaddr))) - elif pnl.af == socket.AF_INET6: - ip = socket.inet_ntop(socket.AF_INET6, (c_char * 16).from_address(addressof(pnl.rdaddr))) - port = socket.ntohs(pnl.rdxport.port) - return (ip, port) - except IOError, e: - return sock.getsockname() - raise + argv = (sock.family, socket.IPPROTO_TCP, peer[0], peer[1], proxy[0], proxy[1]) + pf_command_file.write("QUERY_PF_NAT %r,%r,%s,%r,%s,%r\n" % argv) + pf_command_file.flush() + line = pf_command_file.readline() + debug2("QUERY_PF_NAT %r,%r,%s,%r,%s,%r" % argv + ' > ' + line) + if line.startswith('QUERY_PF_NAT_SUCCESS '): + (ip, port) = line[21:].split(',') + return (ip, int(port)) + return sock.getsockname() def original_dst(sock): try: @@ -815,6 +756,10 @@ def main(listenip_v6, listenip_v4, if dns_listener.v6 is not None: dns_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVORIGDSTADDR, 1) + if fw.method == "pf": + global pf_command_file + pf_command_file = fw.pfile + try: return _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename, python, latency_control, dns_listener, diff --git a/src/firewall.py b/src/firewall.py index b255ee0..058aafe 100644 --- a/src/firewall.py +++ b/src/firewall.py @@ -7,8 +7,13 @@ import compat.ssubprocess as ssubprocess import ssyslog import sys import os +import re from helpers import log, debug1, debug3, islocal, Fatal, family_to_string, \ resolvconf_nameservers +from fcntl import ioctl +from ctypes import c_char, c_uint8, c_uint16, c_uint32, Union, Structure, \ + sizeof, addressof, memmove + # python doesn't have a definition for this IPPROTO_DIVERT = 254 @@ -463,15 +468,23 @@ def do_ipfw(port, dnsport, family, subnets, udp): return do_wait -def pfctl(*args): - argv = ['pfctl'] + list(args) +def pfctl(args, stdin = None): + argv = ['pfctl'] + list(args.split(" ")) debug1('>> %s\n' % ' '.join(argv)) - rv = ssubprocess.Popen(argv, stderr=ssubprocess.PIPE).wait() - if rv: - raise Fatal('%r returned %d' % (argv, rv)) + p = ssubprocess.Popen(argv, stdin = ssubprocess.PIPE, + stdout = ssubprocess.PIPE, + stderr = ssubprocess.PIPE) + o = p.communicate(stdin) + if p.returncode: + raise Fatal('%r returned %d' % (argv, p.returncode)) + + return o + +_pf_context = {'started_by_sshuttle': False, 'Xtoken':''} def do_pf(port, dnsport, family, subnets, udp): + global _pf_started_by_sshuttle tables = [] translating_rules = [] filtering_rules = [] @@ -494,14 +507,27 @@ def do_pf(port, dnsport, family, subnets, udp): translating_rules.append('rdr pass on lo0 proto udp to port 53 -> 127.0.0.1 port %r' % dnsport) filtering_rules.append('pass out route-to lo0 inet proto udp to port 53 keep state') - pf_config_file = '/etc/pf-sshuttle.conf' - with open(pf_config_file, 'w+') as f: - f.write('\n'.join(tables + translating_rules + filtering_rules) + '\n') + rules = '\n'.join(tables + translating_rules + filtering_rules) + '\n' - pfctl('-Ef', pf_config_file) - os.remove(pf_config_file) + pf_status = pfctl('-s all')[0] + if not '\nrdr-anchor "sshuttle" all\n' in pf_status: + pf_add_anchor_rule(PF_RDR, "sshuttle") + if not '\nanchor "sshuttle" all\n' in pf_status: + pf_add_anchor_rule(PF_PASS, "sshuttle") + + pfctl('-a sshuttle -f /dev/stdin', rules) + if sys.platform == "darwin": + o = pfctl('-E') + _pf_context['Xtoken'] = re.search(r'Token : (.+)', o[1]).group(1) + elif 'INFO:\nStatus: Disabled' in pf_status: + pfctl('-e') + _pf_context['started_by_sshuttle'] = True else: - pfctl('-dF', 'all') + pfctl('-a sshuttle -F all') + if sys.platform == "darwin": + pfctl('-X %s' % _pf_context['Xtoken']) + elif _pf_context['started_by_sshuttle']: + pfctl('-d') def program_exists(name): @@ -556,6 +582,106 @@ def restore_etc_hosts(port): rewrite_etc_hosts(port) +# This are some classes and functions used to support pf in yosemite. +class pf_state_xport(Union): + _fields_ = [("port", c_uint16), + ("call_id", c_uint16), + ("spi", c_uint32)] + +class pf_addr(Structure): + class _pfa(Union): + _fields_ = [("v4", c_uint32), # struct in_addr + ("v6", c_uint32 * 4), # struct in6_addr + ("addr8", c_uint8 * 16), + ("addr16", c_uint16 * 8), + ("addr32", c_uint32 * 4)] + + _fields_ = [("pfa", _pfa)] + _anonymous_ = ("pfa",) + +class pfioc_natlook(Structure): + _fields_ = [("saddr", pf_addr), + ("daddr", pf_addr), + ("rsaddr", pf_addr), + ("rdaddr", pf_addr), + ("sxport", pf_state_xport), + ("dxport", pf_state_xport), + ("rsxport", pf_state_xport), + ("rdxport", pf_state_xport), + ("af", c_uint8), # sa_family_t + ("proto", c_uint8), + ("proto_variant", c_uint8), + ("direction", c_uint8)] + +pfioc_rule = c_char * 3104 # sizeof(struct pfioc_rule) + +pfioc_pooladdr = c_char * 1136 # sizeof(struct pfioc_pooladdr) + +MAXPATHLEN = 1024 + +DIOCNATLOOK = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_natlook) & 0x1fff) << 16) | ((ord('D')) << 8) | (23)) +DIOCCHANGERULE = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_rule) & 0x1fff) << 16) | ((ord('D')) << 8) | (26)) +DIOCBEGINADDRS = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_pooladdr) & 0x1fff) << 16) | ((ord('D')) << 8) | (51)) + +PF_CHANGE_ADD_TAIL = 2 +PF_CHANGE_GET_TICKET = 6 + +PF_PASS = 0 +PF_RDR = 8 + +PF_OUT = 2 + +_pf_fd = None + +def pf_get_dev(): + global _pf_fd + if _pf_fd == None: + _pf_fd = os.open('/dev/pf', os.O_RDWR) + + return _pf_fd + +def pf_query_nat(family, proto, src_ip, src_port, dst_ip, dst_port): + [proto, family, src_port, dst_port] = [int(v) for v in [proto, family, src_port, dst_port]] + + length = 4 if family == socket.AF_INET else 16 + + pnl = pfioc_natlook() + pnl.proto = proto + pnl.direction = PF_OUT + pnl.af = family + memmove(addressof(pnl.saddr), socket.inet_pton(pnl.af, src_ip), length) + pnl.sxport.port = socket.htons(src_port) + memmove(addressof(pnl.daddr), socket.inet_pton(pnl.af, dst_ip), length) + pnl.dxport.port = socket.htons(dst_port) + + ioctl(pf_get_dev(), DIOCNATLOOK, (c_char * sizeof(pnl)).from_address(addressof(pnl))) + + ip = socket.inet_ntop(pnl.af, (c_char * length).from_address(addressof(pnl.rdaddr))) + port = socket.ntohs(pnl.rdxport.port) + return (ip, port) + +def pf_add_anchor_rule(type, name): + ACTION_OFFSET = 0 + POOL_TICKET_OFFSET = 8 + ANCHOR_CALL_OFFSET = 1040 + RULE_ACTION_OFFSET = 3068 + + pr = pfioc_rule() + ppa = pfioc_pooladdr() + + ioctl(pf_get_dev(), DIOCBEGINADDRS, ppa) + + memmove(addressof(pr) + POOL_TICKET_OFFSET, ppa[4:8], 4) #pool_ticket + memmove(addressof(pr) + ANCHOR_CALL_OFFSET, name, min(MAXPATHLEN, len(name))) #anchor_call = name + memmove(addressof(pr) + RULE_ACTION_OFFSET, struct.pack('I', type), 4) #rule.action = type + + memmove(addressof(pr) + ACTION_OFFSET, struct.pack('I', PF_CHANGE_GET_TICKET), 4) #action = PF_CHANGE_GET_TICKET + ioctl(pf_get_dev(), DIOCCHANGERULE, pr) + + memmove(addressof(pr) + ACTION_OFFSET, struct.pack('I', PF_CHANGE_ADD_TAIL), 4) #action = PF_CHANGE_ADD_TAIL + ioctl(pf_get_dev(), DIOCCHANGERULE, pr) + + # This is some voodoo for setting up the kernel's transparent # proxying stuff. If subnets is empty, we just delete our sshuttle rules; # otherwise we delete it, then make them from scratch. @@ -682,6 +808,14 @@ def main(port_v6, port_v4, dnsport_v6, dnsport_v4, method, udp, syslog): (name, ip) = line[5:].strip().split(',', 1) hostmap[name] = ip rewrite_etc_hosts(port_v6 or port_v4) + elif line.startswith('QUERY_PF_NAT '): + try: + dst = pf_query_nat(*(line[13:].split(','))) + sys.stdout.write('QUERY_PF_NAT_SUCCESS %s,%r\n' % dst) + except IOError, e: + sys.stdout.write('QUERY_PF_NAT_FAILURE %s\n' % e) + + sys.stdout.flush() elif line: raise Fatal('expected EOF, got %r' % line) else: