54 lines
1.2 KiB
Go
54 lines
1.2 KiB
Go
package ingress
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import (
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"context"
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"fmt"
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"net/netip"
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"time"
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"github.com/rs/zerolog"
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"golang.org/x/net/icmp"
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"github.com/cloudflare/cloudflared/packet"
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)
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const (
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defaultCloseAfterIdle = time.Second * 15
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mtu = 1500
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icmpTimeoutMs = 1000
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)
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var (
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errFlowInactive = fmt.Errorf("flow is inactive")
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errPacketNil = fmt.Errorf("packet is nil")
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)
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// ICMPProxy sends ICMP messages and listens for their responses
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type ICMPProxy interface {
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// Serve starts listening for responses to the requests until context is done
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Serve(ctx context.Context) error
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// Request sends an ICMP message
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Request(pk *packet.ICMP, responder packet.FlowResponder) error
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}
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func NewICMPProxy(listenIP netip.Addr, logger *zerolog.Logger) (ICMPProxy, error) {
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return newICMPProxy(listenIP, logger)
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}
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// Opens a non-privileged ICMP socket on Linux and Darwin
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func newICMPConn(listenIP netip.Addr) (*icmp.PacketConn, error) {
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network := "udp6"
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if listenIP.Is4() {
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network = "udp4"
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}
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return icmp.ListenPacket(network, listenIP.String())
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}
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func getICMPEcho(pk *packet.ICMP) (*icmp.Echo, error) {
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echo, ok := pk.Message.Body.(*icmp.Echo)
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if !ok {
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return nil, fmt.Errorf("expect ICMP echo, got %s", pk.Type)
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}
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return echo, nil
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}
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