diff options
Diffstat (limited to 'pkg/tcpip/iptables/udp_matcher.go')
| -rw-r--r-- | pkg/tcpip/iptables/udp_matcher.go | 62 |
1 files changed, 24 insertions, 38 deletions
diff --git a/pkg/tcpip/iptables/udp_matcher.go b/pkg/tcpip/iptables/udp_matcher.go index 65ae7f9e0..f59ca2027 100644 --- a/pkg/tcpip/iptables/udp_matcher.go +++ b/pkg/tcpip/iptables/udp_matcher.go @@ -16,33 +16,28 @@ package iptables import ( "fmt" - "runtime/debug" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/header" ) +// TODO(gvisor.dev/issue/170): The following per-matcher params should be +// supported: +// - Table name +// - Match size +// - User size +// - Hooks +// - Proto +// - Family + +// UDPMatcher matches UDP packets and their headers. It implements Matcher. type UDPMatcher struct { - Data UDPMatcherData - - // tablename string - // unsigned int matchsize; - // unsigned int usersize; - // #ifdef CONFIG_COMPAT - // unsigned int compatsize; - // #endif - // unsigned int hooks; - // unsigned short proto; - // unsigned short family; + Data UDPMatcherParams } -// TODO: Delete? -// MatchCheckEntryParams - -type UDPMatcherData struct { - // Filter IPHeaderFilter - +// UDPMatcherParams are the parameters used to create a UDPMatcher. +type UDPMatcherParams struct { SourcePortStart uint16 SourcePortEnd uint16 DestinationPortStart uint16 @@ -50,12 +45,12 @@ type UDPMatcherData struct { InverseFlags uint8 } -func NewUDPMatcher(filter IPHeaderFilter, data UDPMatcherData) (Matcher, error) { - // TODO: We currently only support source port and destination port. - log.Infof("Adding rule with UDPMatcherData: %+v", data) +// NewUDPMatcher returns a new instance of UDPMatcher. +func NewUDPMatcher(filter IPHeaderFilter, data UDPMatcherParams) (Matcher, error) { + log.Infof("Adding rule with UDPMatcherParams: %+v", data) if data.InverseFlags != 0 { - return nil, fmt.Errorf("unsupported UDP matcher flags set") + return nil, fmt.Errorf("unsupported UDP matcher inverse flags set") } if filter.Protocol != header.UDPProtocolNumber { @@ -65,21 +60,18 @@ func NewUDPMatcher(filter IPHeaderFilter, data UDPMatcherData) (Matcher, error) return &UDPMatcher{Data: data}, nil } -// TODO: Check xt_tcpudp.c. Need to check for same things (e.g. fragments). +// Match implements Matcher.Match. func (um *UDPMatcher) Match(hook Hook, pkt tcpip.PacketBuffer, interfaceName string) (bool, bool) { - log.Infof("UDPMatcher called from: %s", string(debug.Stack())) netHeader := header.IPv4(pkt.NetworkHeader) - // TODO: Do we check proto here or elsewhere? I think elsewhere (check - // codesearch). + // TODO(gvisor.dev/issue/170): Proto checks should ultimately be moved + // into the iptables.Check codepath as matchers are added. if netHeader.TransportProtocol() != header.UDPProtocolNumber { - log.Infof("UDPMatcher: wrong protocol number") return false, false } // We dont't match fragments. if frag := netHeader.FragmentOffset(); frag != 0 { - log.Infof("UDPMatcher: it's a fragment") if frag == 1 { return false, true } @@ -89,20 +81,18 @@ func (um *UDPMatcher) Match(hook Hook, pkt tcpip.PacketBuffer, interfaceName str // Now we need the transport header. However, this may not have been set // yet. - // TODO + // TODO(gvisor.dev/issue/170): Parsing the transport header should + // ultimately be moved into the iptables.Check codepath as matchers are + // added. var udpHeader header.UDP if pkt.TransportHeader != nil { - log.Infof("UDPMatcher: transport header is not nil") udpHeader = header.UDP(pkt.TransportHeader) } else { - log.Infof("UDPMatcher: transport header is nil") - log.Infof("UDPMatcher: is network header nil: %t", pkt.NetworkHeader == nil) // The UDP header hasn't been parsed yet. We have to do it here. if len(pkt.Data.First()) < header.UDPMinimumSize { // There's no valid UDP header here, so we hotdrop the // packet. - // TODO: Stats. - log.Warningf("Dropping UDP packet: size to small.") + log.Warningf("Dropping UDP packet: size too small.") return false, true } udpHeader = header.UDP(pkt.Data.First()) @@ -112,10 +102,6 @@ func (um *UDPMatcher) Match(hook Hook, pkt tcpip.PacketBuffer, interfaceName str // matching range. sourcePort := udpHeader.SourcePort() destinationPort := udpHeader.DestinationPort() - log.Infof("UDPMatcher: sport and dport are %d and %d. sports and dport start and end are (%d, %d) and (%d, %d)", - udpHeader.SourcePort(), udpHeader.DestinationPort(), - um.Data.SourcePortStart, um.Data.SourcePortEnd, - um.Data.DestinationPortStart, um.Data.DestinationPortEnd) if sourcePort < um.Data.SourcePortStart || um.Data.SourcePortEnd < sourcePort { return false, false } |