iptables

Documentation

Overview

Package iptables manages iptables-related configuration for Cilium.

Index

• func InstallNoTrackRules(IP string, port uint16, ipv6 bool) error
• func KernelHasNetfilter() bool
• func RemoveNoTrackRules(IP string, port uint16, ipv6 bool) error
• type IptablesManager
  • func (m *IptablesManager) GetProxyPort(name string) uint16
  • func (m *IptablesManager) Init()
  • func (m *IptablesManager) InstallProxyRules(proxyPort uint16, ingress bool, name string) error
  • func (m *IptablesManager) InstallRules(ifName string) error
  • func (m *IptablesManager) RemoveProxyRules(proxyPort uint16, ingress bool, name string) error
  • func (m *IptablesManager) RemoveRules(quiet bool)
  • func (m *IptablesManager) SupportsOriginalSourceAddr() bool
  • func (m *IptablesManager) TransientRulesEnd(quiet bool)
  • func (m *IptablesManager) TransientRulesStart(ifName string) error

Functions

func InstallNoTrackRules

func InstallNoTrackRules(IP string, port uint16, ipv6 bool) error

InstallNoTrackRules is explicitly called when a pod has valid "io.cilium.no-track-port" annotation. When InstallNoConntrackIptRules flag is set, a super set of v4 NOTRACK rules will be automatically installed upon agent bootstrap (via function addNoTrackPodTrafficRules) and this function will be skipped. When InstallNoConntrackIptRules is not set, this function will be executed to install NOTRACK rules. The rules installed by this function is very specific, for now, the only user is node-local-dns pods.

func KernelHasNetfilter

func KernelHasNetfilter() bool

KernelHasNetfilter probes whether iptables related modules are present in the kernel and returns true if indeed the case, else false.

func RemoveNoTrackRules

func RemoveNoTrackRules(IP string, port uint16, ipv6 bool) error

See comments for InstallNoTrackRules.

Types

type IptablesManager

type IptablesManager struct {
	// contains filtered or unexported fields
}

IptablesManager manages the iptables-related configuration for Cilium.

func (*IptablesManager) GetProxyPort

func (m *IptablesManager) GetProxyPort(name string) uint16

GetProxyPort finds a proxy port used for redirect 'name' installed earlier with InstallProxyRules. By convention "ingress" or "egress" is part of 'name' so it does not need to be specified explicitly. Returns 0 a TPROXY entry with 'name' can not be found.

func (*IptablesManager) Init

func (m *IptablesManager) Init()

Init initializes the iptables manager and checks for iptables kernel modules availability.

func (*IptablesManager) InstallProxyRules

func (m *IptablesManager) InstallProxyRules(proxyPort uint16, ingress bool, name string) error

func (*IptablesManager) InstallRules

func (m *IptablesManager) InstallRules(ifName string) error

InstallRules installs iptables rules for Cilium in specific use-cases (most specifically, interaction with kube-proxy).

func (*IptablesManager) RemoveProxyRules

func (m *IptablesManager) RemoveProxyRules(proxyPort uint16, ingress bool, name string) error

func (*IptablesManager) RemoveRules

func (m *IptablesManager) RemoveRules(quiet bool)

RemoveRules removes iptables rules installed by Cilium.

func (*IptablesManager) SupportsOriginalSourceAddr

func (m *IptablesManager) SupportsOriginalSourceAddr() bool

SupportsOriginalSourceAddr tells if an L7 proxy can use POD's original source address and port in the upstream connection to allow the destination to properly derive the source security ID from the source IP address.

func (*IptablesManager) TransientRulesEnd

func (m *IptablesManager) TransientRulesEnd(quiet bool)

TransientRulesEnd removes Cilium related rules installed from TransientRulesStart.

func (*IptablesManager) TransientRulesStart

func (m *IptablesManager) TransientRulesStart(ifName string) error

TransientRulesStart installs iptables rules for Cilium that need to be kept in-tact during agent restart which removes/installs its main rules. Transient rules are then removed once iptables rule update cycle has completed. This is mainly due to interactions with kube-proxy.