diff options
Diffstat (limited to 'pkg/tcpip')
| -rw-r--r-- | pkg/tcpip/header/icmpv4.go | 14 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv4/icmp.go | 24 | ||||
| -rw-r--r-- | pkg/tcpip/transport/icmp/endpoint.go | 14 | ||||
| -rw-r--r-- | pkg/tcpip/transport/icmp/protocol.go | 7 |
4 files changed, 22 insertions, 37 deletions
diff --git a/pkg/tcpip/header/icmpv4.go b/pkg/tcpip/header/icmpv4.go index c081de61f..c52c0d851 100644 --- a/pkg/tcpip/header/icmpv4.go +++ b/pkg/tcpip/header/icmpv4.go @@ -24,15 +24,11 @@ import ( type ICMPv4 []byte const ( - // ICMPv4MinimumSize is the minimum size of a valid ICMP packet. - ICMPv4MinimumSize = 4 - - // ICMPv4EchoMinimumSize is the minimum size of a valid ICMP echo packet. - ICMPv4EchoMinimumSize = 6 + // ICMPv4PayloadOffset defines the start of ICMP payload. + ICMPv4PayloadOffset = 4 - // ICMPv4DstUnreachableMinimumSize is the minimum size of a valid ICMP - // destination unreachable packet. - ICMPv4DstUnreachableMinimumSize = ICMPv4MinimumSize + 4 + // ICMPv4MinimumSize is the minimum size of a valid ICMP packet. + ICMPv4MinimumSize = 8 // ICMPv4ProtocolNumber is the ICMP transport protocol number. ICMPv4ProtocolNumber tcpip.TransportProtocolNumber = 1 @@ -104,5 +100,5 @@ func (ICMPv4) SetDestinationPort(uint16) { // Payload implements Transport.Payload. func (b ICMPv4) Payload() []byte { - return b[ICMPv4MinimumSize:] + return b[ICMPv4PayloadOffset:] } diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go index bc7f1c42a..fbef6947d 100644 --- a/pkg/tcpip/network/ipv4/icmp.go +++ b/pkg/tcpip/network/ipv4/icmp.go @@ -68,10 +68,6 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V switch h.Type() { case header.ICMPv4Echo: received.Echo.Increment() - if len(v) < header.ICMPv4EchoMinimumSize { - received.Invalid.Increment() - return - } // Only send a reply if the checksum is valid. wantChecksum := h.Checksum() @@ -93,9 +89,9 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V e.dispatcher.DeliverTransportPacket(r, header.ICMPv4ProtocolNumber, netHeader, vv) vv := vv.Clone(nil) - vv.TrimFront(header.ICMPv4EchoMinimumSize) - hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + header.ICMPv4EchoMinimumSize) - pkt := header.ICMPv4(hdr.Prepend(header.ICMPv4EchoMinimumSize)) + vv.TrimFront(header.ICMPv4MinimumSize) + hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + header.ICMPv4MinimumSize) + pkt := header.ICMPv4(hdr.Prepend(header.ICMPv4MinimumSize)) copy(pkt, h) pkt.SetType(header.ICMPv4EchoReply) pkt.SetChecksum(^header.Checksum(pkt, header.ChecksumVV(vv, 0))) @@ -108,25 +104,19 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V case header.ICMPv4EchoReply: received.EchoReply.Increment() - if len(v) < header.ICMPv4EchoMinimumSize { - received.Invalid.Increment() - return - } + e.dispatcher.DeliverTransportPacket(r, header.ICMPv4ProtocolNumber, netHeader, vv) case header.ICMPv4DstUnreachable: received.DstUnreachable.Increment() - if len(v) < header.ICMPv4DstUnreachableMinimumSize { - received.Invalid.Increment() - return - } - vv.TrimFront(header.ICMPv4DstUnreachableMinimumSize) + + vv.TrimFront(header.ICMPv4MinimumSize) switch h.Code() { case header.ICMPv4PortUnreachable: e.handleControl(stack.ControlPortUnreachable, 0, vv) case header.ICMPv4FragmentationNeeded: - mtu := uint32(binary.BigEndian.Uint16(v[header.ICMPv4DstUnreachableMinimumSize-2:])) + mtu := uint32(binary.BigEndian.Uint16(v[header.ICMPv4PayloadOffset+2:])) e.handleControl(stack.ControlPacketTooBig, calculateMTU(mtu), vv) } diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go index ab9e80747..a80ceafd0 100644 --- a/pkg/tcpip/transport/icmp/endpoint.go +++ b/pkg/tcpip/transport/icmp/endpoint.go @@ -291,7 +291,7 @@ func (e *endpoint) Write(p tcpip.Payload, opts tcpip.WriteOptions) (uintptr, <-c switch e.netProto { case header.IPv4ProtocolNumber: - err = e.send4(route, v) + err = send4(route, e.id.LocalPort, v) case header.IPv6ProtocolNumber: err = send6(route, e.id.LocalPort, v) @@ -352,20 +352,20 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { } } -func (e *endpoint) send4(r *stack.Route, data buffer.View) *tcpip.Error { - if len(data) < header.ICMPv4EchoMinimumSize { +func send4(r *stack.Route, ident uint16, data buffer.View) *tcpip.Error { + if len(data) < header.ICMPv4MinimumSize { return tcpip.ErrInvalidEndpointState } // Set the ident to the user-specified port. Sequence number should // already be set by the user. - binary.BigEndian.PutUint16(data[header.ICMPv4MinimumSize:], e.id.LocalPort) + binary.BigEndian.PutUint16(data[header.ICMPv4PayloadOffset:], ident) - hdr := buffer.NewPrependable(header.ICMPv4EchoMinimumSize + int(r.MaxHeaderLength())) + hdr := buffer.NewPrependable(header.ICMPv4MinimumSize + int(r.MaxHeaderLength())) - icmpv4 := header.ICMPv4(hdr.Prepend(header.ICMPv4EchoMinimumSize)) + icmpv4 := header.ICMPv4(hdr.Prepend(header.ICMPv4MinimumSize)) copy(icmpv4, data) - data = data[header.ICMPv4EchoMinimumSize:] + data = data[header.ICMPv4MinimumSize:] // Linux performs these basic checks. if icmpv4.Type() != header.ICMPv4Echo || icmpv4.Code() != 0 { diff --git a/pkg/tcpip/transport/icmp/protocol.go b/pkg/tcpip/transport/icmp/protocol.go index c89538131..7fdba5d56 100644 --- a/pkg/tcpip/transport/icmp/protocol.go +++ b/pkg/tcpip/transport/icmp/protocol.go @@ -90,19 +90,18 @@ func (p *protocol) NewRawEndpoint(stack *stack.Stack, netProto tcpip.NetworkProt func (p *protocol) MinimumPacketSize() int { switch p.number { case ProtocolNumber4: - return header.ICMPv4EchoMinimumSize + return header.ICMPv4MinimumSize case ProtocolNumber6: return header.ICMPv6EchoMinimumSize } panic(fmt.Sprint("unknown protocol number: ", p.number)) } -// ParsePorts returns the source and destination ports stored in the given icmp -// packet. +// ParsePorts in case of ICMP sets src to 0, dst to ICMP ID, and err to nil. func (p *protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) { switch p.number { case ProtocolNumber4: - return 0, binary.BigEndian.Uint16(v[header.ICMPv4MinimumSize:]), nil + return 0, binary.BigEndian.Uint16(v[header.ICMPv4PayloadOffset:]), nil case ProtocolNumber6: return 0, binary.BigEndian.Uint16(v[header.ICMPv6MinimumSize:]), nil } |