diff options
Diffstat (limited to 'node/Filter.cpp')
-rw-r--r-- | node/Filter.cpp | 108 |
1 files changed, 107 insertions, 1 deletions
diff --git a/node/Filter.cpp b/node/Filter.cpp index 8a41b3f9..1f81a360 100644 --- a/node/Filter.cpp +++ b/node/Filter.cpp @@ -39,11 +39,16 @@ bool Filter::Rule::operator()(unsigned int etype,const void *data,unsigned int l if ((!_etherType)||(_etherType(etype))) { // ethertype is ANY, or matches // Ethertype determines meaning of protocol and port switch(etype) { + default: + if ((!_protocol)&&(!_port)) + return true; // match other ethertypes if protocol and port are ANY, since we don't know what to do with them + break; + case ZT_ETHERTYPE_IPV4: if (len > 20) { if ((!_protocol)||(_protocol(((const uint8_t *)data)[9]))) { // IP protocol if (!_port) - return true; // protocol matches, port is ANY + return true; // protocol matches or is ANY, port is ANY // Don't match on fragments beyond fragment 0. If we've blocked // fragment 0, further fragments will fall on deaf ears anyway. @@ -71,6 +76,52 @@ bool Filter::Rule::operator()(unsigned int etype,const void *data,unsigned int l case ZT_ETHERTYPE_IPV6: if (len > 40) { // see: http://stackoverflow.com/questions/17518951/is-the-ipv6-header-really-this-nutty + int nextHeader = ((const uint8_t *)data)[6]; + unsigned int pos = 40; + while ((pos < len)&&(nextHeader >= 0)&&(nextHeader != 59)) { // 59 == no next header + fprintf(stderr,"[rule] V6: start header parse, header %.2x pos %d\n",nextHeader,pos); + + switch(nextHeader) { + case 0: // hop-by-hop options + case 60: // destination options + case 43: // routing + case 135: // mobility (mobile IPv6 options) + if (_protocol((unsigned int)nextHeader)) + return true; // match if our goal was to match any of these + nextHeader = ((const uint8_t *)data)[pos]; + pos += 8 + (8 * ((const uint8_t *)data)[pos + 1]); + break; + case 44: // fragment + if (_protocol(44)) + return true; // match if our goal was to match fragments + nextHeader = ((const uint8_t *)data)[pos]; + pos += 8; + break; + case ZT_IPPROTO_AH: // AH + return _protocol(ZT_IPPROTO_AH); // true if AH is matched protocol, otherwise false since packet will be IPsec + case ZT_IPPROTO_ESP: // ESP + return _protocol(ZT_IPPROTO_ESP); // true if ESP is matched protocol, otherwise false since packet will be IPsec + case ZT_IPPROTO_ICMPV6: + if (_protocol(ZT_IPPROTO_ICMPV6)) { // only match ICMPv6 if specified + if ((!_port)||(_port(((const uint8_t *)data)[pos]))) + return true; // protocol matches, port is ANY or matches ICMP type + } + break; + case ZT_IPPROTO_TCP: + case ZT_IPPROTO_UDP: + case ZT_IPPROTO_SCTP: + case ZT_IPPROTO_UDPLITE: + // If we encounter any of these, match if protocol matches or is wildcard as + // we'll consider these the "real payload" if present. + if ((!_protocol)||(_protocol(nextHeader))) { + if ((!_port)||(_port(((const uint16_t *)data)[(pos / 2) + 1]))) + return true; // protocol matches or is ANY, port is ANY or matches + } + break; + } + + fprintf(stderr,"[rule] V6: end header parse, next header %.2x, new pos %d\n",nextHeader,pos); + } } break; } @@ -100,6 +151,61 @@ void Filter::add(const Rule &r,const Action &a) _chain.push_back(Entry(r,a)); } +std::string Filter::toString(const char *sep) const +{ + char buf[256]; + + if (!sep) + sep = ","; + + std::string s; + + Mutex::Lock _l(_chain_m); + for(std::vector<Entry>::const_iterator i(_chain.begin());i!=_chain.end();++i) { + bool first = (i == _chain.begin()); + + s.push_back('['); + + if (i->rule.etherType()) { + sprintf(buf,"%u-%u",i->rule.etherType().start,i->rule.etherType().end); + s.append(buf); + } else s.push_back('*'); + + s.push_back(';'); + + if (i->rule.protocol()) { + sprintf(buf,"%u-%u",i->rule.protocol().start,i->rule.protocol().end); + s.append(buf); + } else s.push_back('*'); + + s.push_back(';'); + + if (i->rule.port()) { + sprintf(buf,"%u-%u",i->rule.port().start,i->rule.port().end); + s.append(buf); + } else s.push_back('*'); + + s.append("]:"); + + switch(i->action) { + case ACTION_DENY: + s.append("DENY"); + break; + case ACTION_ALLOW: + s.append("ALLOW"); + break; + case ACTION_LOG: + s.append("LOG"); + break; + } + + if (!first) + s.append(sep); + } + + return s; +} + const char *Filter::etherTypeName(const unsigned int etherType) throw() { |