datapath

Documentation

Overview

Package datapath defines the interfaces to abstract all platform specific datapath components.

Current datapath implementations:

pkg/datapath/linux
pkg/datapath/fake

Index

• func RemoteSNATDstAddrExclusionCIDRv4() *cidr.CIDR
• func RemoteSNATDstAddrExclusionCIDRv6() *cidr.CIDR
• type BaseProgramOwner
• type CompileTimeConfiguration
• type ConfigWriter
• type Datapath
• type DeviceConfiguration
• type Endpoint
• type EndpointConfiguration
• type IptablesManager
• type LoadTimeConfiguration
• type Loader
• type LocalNodeConfiguration
• type NodeHandler
• type PreFilter
• type Proxy
• type WireguardAgent

Functions

func RemoteSNATDstAddrExclusionCIDRv4

func RemoteSNATDstAddrExclusionCIDRv4() *cidr.CIDR

RemoteSNATDstAddrExclusionCIDRv4 returns a CIDR for SNAT exclusion. Any packet sent from a local endpoint to an IP address belonging to the CIDR should not be SNAT'd.

func RemoteSNATDstAddrExclusionCIDRv6

func RemoteSNATDstAddrExclusionCIDRv6() *cidr.CIDR

RemoteSNATDstAddrExclusionCIDRv6 returns a IPv6 CIDR for SNAT exclusion. Any packet sent from a local endpoint to an IP address belonging to the CIDR should not be SNAT'd.

Types

type BaseProgramOwner

type BaseProgramOwner interface {
	DeviceConfiguration
	GetCompilationLock() *lock.RWMutex
	Datapath() Datapath
	LocalConfig() *LocalNodeConfiguration
	SetPrefilter(pf PreFilter)
}

BaseProgramOwner is any type for which a loader is building base programs.

type CompileTimeConfiguration

type CompileTimeConfiguration interface {
	DeviceConfiguration

	// TODO: Move this detail into the datapath
	ConntrackLocalLocked() bool

	// RequireARPPassthrough returns true if the datapath must implement
	// ARP passthrough for this endpoint
	RequireARPPassthrough() bool

	// RequireEgressProg returns true if the endpoint requires an egress
	// program attached to the InterfaceName() invoking the section
	// "to-container"
	RequireEgressProg() bool

	// RequireRouting returns true if the endpoint requires BPF routing to
	// be enabled, when disabled, routing is delegated to Linux routing
	RequireRouting() bool

	// RequireEndpointRoute returns true if the endpoint wishes to have a
	// per endpoint route installed in the host's routing table to point to
	// the endpoint's interface
	RequireEndpointRoute() bool

	// GetPolicyVerdictLogFilter returns the PolicyVerdictLogFilter for the endpoint
	GetPolicyVerdictLogFilter() uint32

	// IsHost returns true if the endpoint is the host endpoint.
	IsHost() bool

	// DisableSIPVerification returns true if the endpoint wishes to skip
	// source IP verification
	DisableSIPVerification() bool
}

CompileTimeConfiguration provides datapath implementations a clean interface to access endpoint-specific configuration that can only be changed at compile time.

type ConfigWriter

type ConfigWriter interface {
	// WriteNodeConfig writes the implementation-specific configuration of
	// node-wide options into the specified writer.
	WriteNodeConfig(io.Writer, *LocalNodeConfiguration) error

	// WriteNetdevConfig writes the implementation-specific configuration
	// of configurable options to the specified writer. Options specified
	// here will apply to base programs and not to endpoints, though
	// endpoints may have equivalent configurable options.
	WriteNetdevConfig(io.Writer, DeviceConfiguration) error

	// WriteTemplateConfig writes the implementation-specific configuration
	// of configurable options for BPF templates to the specified writer.
	WriteTemplateConfig(w io.Writer, cfg EndpointConfiguration) error

	// WriteEndpointConfig writes the implementation-specific configuration
	// of configurable options for the endpoint to the specified writer.
	WriteEndpointConfig(w io.Writer, cfg EndpointConfiguration) error
}

ConfigWriter is anything which writes the configuration for various datapath program types.

type Datapath

type Datapath interface {
	ConfigWriter
	IptablesManager

	// Node must return the handler for node events
	Node() NodeHandler

	// LocalNodeAddressing must return the node addressing implementation
	// of the local node
	LocalNodeAddressing() types.NodeAddressing

	// Loader must return the implementation of the loader, which is responsible
	// for loading, reloading, and compiling datapath programs.
	Loader() Loader

	// WireguardAgent returns the Wireguard agent for the local node
	WireguardAgent() WireguardAgent

	// LBMap returns the load-balancer map
	LBMap() types.LBMap

	Procfs() string
}

Datapath is the interface to abstract all datapath interactions. The abstraction allows to implement the datapath requirements with multiple implementations

type DeviceConfiguration

type DeviceConfiguration interface {
	// GetCIDRPrefixLengths fetches the lists of unique IPv6 and IPv4
	// prefix lengths used for datapath lookups, each of which is sorted
	// from longest prefix to shortest prefix. It must return more than
	// one element in each returned array.
	GetCIDRPrefixLengths() (s6, s4 []int)

	// GetOptions fetches the configurable datapath options from the owner.
	GetOptions() *option.IntOptions
}

DeviceConfiguration is an interface for injecting configuration of datapath options that affect lookups and logic applied at a per-device level, whether those are devices associated with the endpoint or associated with the host.

type Endpoint

type Endpoint interface {
	EndpointConfiguration
	InterfaceName() string
	Logger(subsystem string) *logrus.Entry
	StateDir() string
}

Endpoint provides access endpoint configuration information that is necessary to compile and load the datapath.

type EndpointConfiguration

type EndpointConfiguration interface {
	CompileTimeConfiguration
	LoadTimeConfiguration
}

EndpointConfiguration provides datapath implementations a clean interface to access endpoint-specific configuration when configuring the datapath.

type IptablesManager

type IptablesManager interface {
	// InstallProxyRules creates the necessary datapath config (e.g., iptables
	// rules for redirecting host proxy traffic on a specific ProxyPort)
	InstallProxyRules(ctx context.Context, proxyPort uint16, ingress bool, name string) error

	// SupportsOriginalSourceAddr tells if the datapath supports
	// use of original source addresses in proxy upstream
	// connections.
	SupportsOriginalSourceAddr() bool
	InstallRules(ctx context.Context, ifName string, quiet, install bool) error

	// GetProxyPort fetches the existing proxy port configured for the
	// specified listener. Used early in bootstrap to reopen proxy ports.
	GetProxyPort(listener string) uint16

	// InstallNoTrackRules is explicitly called when a pod has valid
	// "policy.cilium.io/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.
	InstallNoTrackRules(IP string, port uint16, ipv6 bool) error

	// See comments for InstallNoTrackRules.
	RemoveNoTrackRules(IP string, port uint16, ipv6 bool) error
}

IptablesManager manages iptables rules.

type LoadTimeConfiguration

type LoadTimeConfiguration interface {
	// GetID returns a locally-significant endpoint identification number.
	GetID() uint64
	// StringID returns the string-formatted version of the ID from GetID().
	StringID() string
	// GetIdentity returns a globally-significant numeric security identity.
	GetIdentity() identity.NumericIdentity

	// GetIdentityLocked returns a globally-significant numeric security
	// identity while assuming that the backing data structure is locked.
	// This function should be removed in favour of GetIdentity()
	GetIdentityLocked() identity.NumericIdentity

	IPv4Address() netip.Addr
	IPv6Address() netip.Addr
	GetNodeMAC() mac.MAC
}

LoadTimeConfiguration provides datapath implementations a clean interface to access endpoint-specific configuration that can be changed at load time.

type Loader

type Loader interface {
	CallsMapPath(id uint16) string
	CustomCallsMapPath(id uint16) string
	CompileAndLoad(ctx context.Context, ep Endpoint, stats *metrics.SpanStat) error
	CompileOrLoad(ctx context.Context, ep Endpoint, stats *metrics.SpanStat) error
	ReloadDatapath(ctx context.Context, ep Endpoint, stats *metrics.SpanStat) error
	EndpointHash(cfg EndpointConfiguration) (string, error)
	Unload(ep Endpoint)
	Reinitialize(ctx context.Context, o BaseProgramOwner, deviceMTU int, iptMgr IptablesManager, p Proxy) error
}

Loader is an interface to abstract out loading of datapath programs.

type LocalNodeConfiguration

type LocalNodeConfiguration struct {
	// MtuConfig is the MTU configuration of the node.
	//
	// This field is immutable at runtime. The value will not change in
	// subsequent calls to NodeConfigurationChanged().
	MtuConfig mtu.Configuration

	// AuxiliaryPrefixes is the list of auxiliary prefixes that should be
	// configured in addition to the node PodCIDR
	//
	// This field is mutable. The implementation of
	// NodeConfigurationChanged() must adjust the routes accordingly.
	AuxiliaryPrefixes []*cidr.CIDR

	// EnableIPv4 enables use of IPv4. Routing to the IPv4 allocation CIDR
	// of other nodes must be enabled.
	//
	// This field is immutable at runtime. The value will not change in
	// subsequent calls to NodeConfigurationChanged().
	EnableIPv4 bool

	// EnableIPv6 enables use of IPv6. Routing to the IPv6 allocation CIDR
	// of other nodes must be enabled.
	//
	// This field is immutable at runtime. The value will not change in
	// subsequent calls to NodeConfigurationChanged().
	EnableIPv6 bool

	// UseSingleClusterRoute enables the use of a single cluster-wide route
	// to direct traffic from the host into the Cilium datapath.  This
	// avoids the requirement to install a separate route for each node
	// CIDR and can thus improve the overhead when operating large clusters
	// with significant node event churn due to auto-scaling.
	//
	// Use of UseSingleClusterRoute must be compatible with
	// EnableAutoDirectRouting. When both are enabled, any direct node
	// route must take precedence over the cluster-wide route as per LPM
	// routing definition.
	//
	// This field is mutable. The implementation of
	// NodeConfigurationChanged() must adjust the routes accordingly.
	UseSingleClusterRoute bool

	// EnableEncapsulation enables use of encapsulation in communication
	// between nodes.
	//
	// This field is immutable at runtime. The value will not change in
	// subsequent calls to NodeConfigurationChanged().
	EnableEncapsulation bool

	// EnableAutoDirectRouting enables the use of direct routes for
	// communication between nodes if two nodes have direct L2
	// connectivity.
	//
	// EnableAutoDirectRouting must be compatible with EnableEncapsulation
	// and must provide a fallback to use encapsulation if direct routing
	// is not feasible and encapsulation is enabled.
	//
	// This field is immutable at runtime. The value will not change in
	// subsequent calls to NodeConfigurationChanged().
	EnableAutoDirectRouting bool

	// EnableLocalNodeRoute enables installation of the route which points
	// the allocation prefix of the local node. Disabling this option is
	// useful when another component is responsible for the routing of the
	// allocation CIDR IPs into Cilium endpoints.
	EnableLocalNodeRoute bool

	// EnableIPSec enables IPSec routes
	EnableIPSec bool

	// EncryptNode enables encrypting NodeIP traffic requires EnableIPSec
	EncryptNode bool

	// IPv4PodSubnets is a list of IPv4 subnets that pod IPs are assigned from
	// these are then used when encryption is enabled to configure the node
	// for encryption over these subnets at node initialization.
	IPv4PodSubnets []*net.IPNet

	// IPv6PodSubnets is a list of IPv6 subnets that pod IPs are assigned from
	// these are then used when encryption is enabled to configure the node
	// for encryption over these subnets at node initialization.
	IPv6PodSubnets []*net.IPNet
}

LocalNodeConfiguration represents the configuration of the local node

type NodeHandler

type NodeHandler interface {
	// NodeAdd is called when a node is discovered for the first time.
	NodeAdd(newNode nodeTypes.Node) error

	// NodeUpdate is called when a node definition changes. Both the old
	// and new node definition is provided. NodeUpdate() is never called
	// before NodeAdd() is called for a particular node.
	NodeUpdate(oldNode, newNode nodeTypes.Node) error

	// NodeDelete is called after a node has been deleted
	NodeDelete(node nodeTypes.Node) error

	// NodeValidateImplementation is called to validate the implementation of
	// the node in the datapath. This function is intended to be run on an
	// interval to ensure that the datapath is consistently converged.
	NodeValidateImplementation(node nodeTypes.Node) error

	// NodeConfigurationChanged is called when the local node configuration
	// has changed
	NodeConfigurationChanged(config LocalNodeConfiguration) error

	// NodeNeighDiscoveryEnabled returns whether node neighbor discovery is enabled
	NodeNeighDiscoveryEnabled() bool

	// NodeNeighborRefresh is called to refresh node neighbor table
	NodeNeighborRefresh(ctx context.Context, node nodeTypes.Node)

	// NodeCleanNeighbors cleans all neighbor entries for the direct routing device
	// and the encrypt interface.
	NodeCleanNeighbors(migrateOnly bool)

	// AllocateNodeID allocates a new ID for the given node (by IP) if one wasn't
	// already assigned.
	AllocateNodeID(net.IP) uint16

	// DumpNodeIDs returns all node IDs and their associated IP addresses.
	DumpNodeIDs() []*models.NodeID

	// RestoreNodeIDs restores node IDs and their associated IP addresses from the
	// BPF map and into the node handler in-memory copy.
	RestoreNodeIDs()
}

NodeHandler handles node related events such as addition, update or deletion of nodes or changes to the local node configuration.

Node events apply to the local node as well as to remote nodes. The implementation can differ between the own local node and remote nodes by calling node.IsLocal().

type PreFilter

type PreFilter interface {
	WriteConfig(fw io.Writer)
	Dump(to []string) ([]string, int64)
	Insert(revision int64, cidrs []net.IPNet) error
	Delete(revision int64, cidrs []net.IPNet) error
}

PreFilter an interface for an XDP pre-filter.

type Proxy

type Proxy interface {
	ReinstallRules(ctx context.Context) error
}

Proxy is any type which installs rules related to redirecting traffic to a proxy.

type WireguardAgent

type WireguardAgent interface {
	UpdatePeer(nodeName, pubKeyHex string, nodeIPv4, nodeIPv6 net.IP) error
	DeletePeer(nodeName string) error
	Status(includePeers bool) (*models.WireguardStatus, error)
}

WireguardAgent manages the Wireguard peers