linuxitems

package
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 Go to latest Published: May 1, 2024 License: Apache-2.0 Imports: 21 Imported by: 0

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Constants

View Source 
const (
	// VIFTypename : typename for VIF.
	VIFTypename = "VIF"
	// IPRuleTypename : typename for Linux IP rules.
	IPRuleTypename = "IPRule"
	// BridgeTypename : typename for Linux bridges.
	BridgeTypename = "Bridge"
	// BridgePortTypename : typename for network interface added into a Linux bridge.
	BridgePortTypename = "BridgePort"
	// DummyIfTypename : typename for Linux dummy interface.
	DummyIfTypename = "DummyInterface"
	// VLANBridgeTypename : typename for (Linux bridge) enabled for VLANs.
	VLANBridgeTypename = "VLANBridge"
	// VLANPortTypename : typename for bridged port with configured VLAN(s).
	VLANPortTypename = "VLANPort"
	// SysctlTypename : typename for kernel config applied via sysctl.
	SysctlTypename = "Sysctl"
)

Variables

This section is empty.

Functions

func RegisterItems 

func RegisterItems(log *base.LogObject, registry *reconciler.DefaultRegistry,
	monitor netmonitor.NetworkMonitor) error

RegisterItems : register all configurators implemented by this package.

Types

type AccessPort 

type AccessPort struct {
	VID uint16
}

AccessPort : port carries untagged traffic from a single VLAN.

type Bridge 

type Bridge struct {
	// IfName : name of the bridge interface inside the network stack.
	IfName string
	// CreatedByNIM : true if this bridge was created by NIM to extend the bridge domain
	// of an uplink interface. Such bridge is then directly used for L2 network instances.
	CreatedByNIM bool
	// MACAddress : MAC address allocated for (or already assigned by NIM to) the bridge.
	MACAddress net.HardwareAddr
	// IPAddresses : a set of IP addresses allocated for the bridge itself (L3 NI),
	// or already assigned by the DHCP client (NIM-created bridge, L2 NI).
	IPAddresses []*net.IPNet
}

Bridge : Linux bridge.

func (Bridge) Dependencies 

func (b Bridge) Dependencies() (deps []dg.Dependency)

Dependencies returns reservations of IPs that bridge should have assigned.

func (Bridge) Equal 

func (b Bridge) Equal(other dg.Item) bool

Equal compares two Bridge instances.

func (Bridge) External 

func (b Bridge) External() bool

External returns true if it was created by NIM and not be zedrouter.

func (Bridge) GetAssignedIPs 

func (b Bridge) GetAssignedIPs() []*net.IPNet

GetAssignedIPs returns IP addresses assigned to the bridge interface. The function is needed for the definition of dependencies for dnsmasq and HTTP server.

func (Bridge) Label 

func (b Bridge) Label() string

Label is not provided.

func (Bridge) Name 

func (b Bridge) Name() string

Name returns the physical interface name.

func (Bridge) String 

func (b Bridge) String() string

String describes Bridge.

func (Bridge) Type 

func (b Bridge) Type() string

Type of the item.

type BridgeConfigurator 

type BridgeConfigurator struct {
	Log *base.LogObject
}

BridgeConfigurator implements Configurator interface (libs/reconciler) for Linux bridge.

func (*BridgeConfigurator) Create 

func (c *BridgeConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds new Linux bridge.

func (*BridgeConfigurator) Delete 

func (c *BridgeConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes Linux bridge.

func (*BridgeConfigurator) Modify 

func (c *BridgeConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*BridgeConfigurator) NeedsRecreate 

func (c *BridgeConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate always returns true - Modify is not implemented.

type BridgePort 

type BridgePort struct {
	// BridgeIfName : interface name of the bridge.
	BridgeIfName string
	// Variant : port should be one of the supported variants.
	Variant BridgePortVariant
}

BridgePort : network interface added into a Linux bridge.

func (BridgePort) Dependencies 

func (p BridgePort) Dependencies() (deps []dg.Dependency)

Dependencies returns the bridge and the port as the dependencies.

func (BridgePort) Equal 

func (p BridgePort) Equal(other dg.Item) bool

Equal compares two BridgePort instances.

func (BridgePort) External 

func (p BridgePort) External() bool

External returns false.

func (BridgePort) Label 

func (p BridgePort) Label() string

Label for VLANPort.

func (BridgePort) Name 

func (p BridgePort) Name() string

Name returns the interface name of the bridged port

func (BridgePort) String 

func (p BridgePort) String() string

String describes BridgePort.

func (BridgePort) Type 

func (p BridgePort) Type() string

Type of the item.

type BridgePortConfigurator 

type BridgePortConfigurator struct {
	Log            *base.LogObject
	NetworkMonitor netmonitor.NetworkMonitor
}

BridgePortConfigurator implements Configurator interface (libs/reconciler) for Linux bridge port.

func (*BridgePortConfigurator) Create 

func (c *BridgePortConfigurator) Create(ctx context.Context, item dg.Item) error

Create attaches port to a bridge.

func (*BridgePortConfigurator) Delete 

func (c *BridgePortConfigurator) Delete(ctx context.Context, item dg.Item) (err error)

Delete detaches port from the bridge.

func (*BridgePortConfigurator) Modify 

func (c *BridgePortConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*BridgePortConfigurator) NeedsRecreate 

func (c *BridgePortConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true - Modify is not implemented.

type BridgePortVariant 

type BridgePortVariant struct {
	// UplinkIfName : bridged uplink interface.
	UplinkIfName string
	// VIFIfName : bridged VIF.
	VIFIfName string
}

BridgePortVariant is like union, only one option should have non-zero value.

type ContainerApp 

type ContainerApp struct {
	ID uuid.UUID
	// NetNsName : name of a file under /var/run/netns/ dir, referencing network
	// namespace of the (container) app.
	NetNsName string
}

ContainerApp : container application separated from the host only using Linux namespaces.

type DummyIf 

type DummyIf struct {
	// IfName : name of the DummyIf interface inside the network stack.
	IfName string
	// ARPOff : enable to suppress ARP on the dummy interface.
	ARPOff bool
}

DummyIf : Linux dummy interface.

func (DummyIf) Dependencies 

func (d DummyIf) Dependencies() (deps []dg.Dependency)

Dependencies returns no dependencies.

func (DummyIf) Equal 

func (d DummyIf) Equal(other dg.Item) bool

Equal compares two DummyIf instances.

func (DummyIf) External 

func (d DummyIf) External() bool

External returns false.

func (DummyIf) Label 

func (d DummyIf) Label() string

Label is not provided.

func (DummyIf) Name 

func (d DummyIf) Name() string

Name returns the physical interface name.

func (DummyIf) String 

func (d DummyIf) String() string

String describes DummyIf.

func (DummyIf) Type 

func (d DummyIf) Type() string

Type of the item.

type DummyIfConfigurator 

type DummyIfConfigurator struct {
	Log *base.LogObject
}

DummyIfConfigurator implements Configurator interface (libs/reconciler) for Linux dummy interface.

func (*DummyIfConfigurator) Create 

func (c *DummyIfConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds new Linux dummy interface.

func (*DummyIfConfigurator) Delete 

func (c *DummyIfConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes Linux dummy interface.

func (*DummyIfConfigurator) Modify 

func (c *DummyIfConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*DummyIfConfigurator) NeedsRecreate 

func (c *DummyIfConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate always returns true - Modify is not implemented.

type IPRule 

type IPRule struct {
	Priority int
	Table    int
	Mark     int
	Mask     int
	Src      *net.IPNet
	Dst      *net.IPNet
}

IPRule : Linux IP rule.

func (IPRule) Dependencies 

func (r IPRule) Dependencies() (deps []dg.Dependency)

Dependencies returns no dependencies (table does not have to exist).

func (IPRule) Equal 

func (r IPRule) Equal(other dg.Item) bool

Equal compares two IPRule instances.

func (IPRule) External 

func (r IPRule) External() bool

External returns false.

func (IPRule) Label 

func (r IPRule) Label() string

Label is more human-readable than name. Label resembles the output of "ip rule list".

func (IPRule) Name 

func (r IPRule) Name() string

Name combines all attributes to construct a unique identifier for IP rule.

func (IPRule) String 

func (r IPRule) String() string

String describes IPRule in detail.

func (IPRule) Type 

func (r IPRule) Type() string

Type of the item.

type IPRuleConfigurator 

type IPRuleConfigurator struct {
	Log *base.LogObject
}

IPRuleConfigurator implements Configurator interface (libs/reconciler) for Linux IP rule.

func (*IPRuleConfigurator) Create 

func (c *IPRuleConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds IP rule.

func (*IPRuleConfigurator) Delete 

func (c *IPRuleConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes IP rule.

func (*IPRuleConfigurator) Modify 

func (c *IPRuleConfigurator) Modify(_ context.Context, _, _ dg.Item) (err error)

Modify is not implemented.

func (*IPRuleConfigurator) NeedsRecreate 

func (c *IPRuleConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true - Modify is not implemented.

type IPSet 

type IPSet struct {
	// SetName : name of the IPSet.
	// See "SETNAME" in https://ipset.netfilter.org/ipset.man.html.
	SetName string
	// TypeName : type of the IPSet.
	// See "TYPENAME" in https://ipset.netfilter.org/ipset.man.html.
	// See "SET TYPES" on that website for the summary of available types.
	TypeName string
	// AddrFamily should be either AF_INET or AF_INET6.
	AddrFamily int
	// Entries : set of entries added to the IPSet.
	// Entry syntax depends on the type, for example "192.168.1.1,udp:53"
	// would be valid for typename "hash:ip,port".
	Entries []string
}

IPSet : Linux ipset (https://ipset.netfilter.org/index.html).

func (IPSet) Dependencies 

func (s IPSet) Dependencies() (deps []dg.Dependency)

Dependencies returns no dependencies.

func (IPSet) Equal 

func (s IPSet) Equal(other dg.Item) bool

Equal compares two IPSet instances.

func (IPSet) External 

func (s IPSet) External() bool

External returns false.

func (IPSet) Label 

func (s IPSet) Label() string

Label is not provided.

func (IPSet) Name 

func (s IPSet) Name() string

Name returns the IPSet name.

func (IPSet) String 

func (s IPSet) String() string

String describes IPSet.

func (IPSet) Type 

func (s IPSet) Type() string

Type of the item.

type IPSetConfigurator 

type IPSetConfigurator struct {
	Log *base.LogObject
}

IPSetConfigurator implements Configurator interface (libs/reconciler) for Linux ipset (from netfilter).

func (*IPSetConfigurator) Create 

func (c *IPSetConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds new ipset.

func (*IPSetConfigurator) Delete 

func (c *IPSetConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes ipset.

func (*IPSetConfigurator) Modify 

func (c *IPSetConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented. Note that zedrouter does not need to ever modify Entries - they are either static or dynamically managed by dnsmasq, i.e. outside zedrouter.

func (*IPSetConfigurator) NeedsRecreate 

func (c *IPSetConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate always returns true - Modify is not implemented.

type Route 

type Route struct {
	// Non-zero Route.LinkIndex should match OutputIf.
	// If Route.LinkIndex is zero, RouteConfigurator will find the output interface
	// index.
	netlink.Route
	// OutputIf : output interface for the routed traffic.
	// Leave undefined if the destination is unreachable.
	OutputIf genericitems.NetworkIf
	// GwViaLinkRoute is set to true if gateway is not included in the output interface
	// subnet and therefore depends on a link route (RT_SCOPE_LINK) for reachability.
	GwViaLinkRoute bool
	// ForApp is defined if route is configured inside app network namespace.
	ForApp ContainerApp
}

Route : Network route.

func (Route) Dependencies 

func (r Route) Dependencies() (deps []dg.Dependency)

Dependencies of a network route are:

  • the "via" interface must exist and be UP
  • the "via" interface must have an IP address assigned from the subnet of the route gateway.
  • if route has src IP, this IP must be assigned to the "via" interface

func (Route) Equal 

func (r Route) Equal(other dg.Item) bool

Equal compares two Route instances.

func (Route) External 

func (r Route) External() bool

External returns false.

func (Route) Label 

func (r Route) Label() string

Label is more human-readable than name.

func (Route) Name 

func (r Route) Name() string

Name combines the app UUID, output interface name, route table ID and the destination address to construct a unique route identifier.

func (Route) String 

func (r Route) String() string

String describes Route in detail.

func (Route) Type 

func (r Route) Type() string

Type of the item.

type RouteConfigurator 

type RouteConfigurator struct {
	Log            *base.LogObject
	NetworkMonitor netmonitor.NetworkMonitor
}

RouteConfigurator implements Configurator interface (libs/reconciler) for network routes.

func (*RouteConfigurator) Create 

func (c *RouteConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds network route.

func (*RouteConfigurator) Delete 

func (c *RouteConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes network route.

func (*RouteConfigurator) Modify 

func (c *RouteConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*RouteConfigurator) NeedsRecreate 

func (c *RouteConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true - Modify is not implemented.

type Sysctl 

type Sysctl struct {
	// ForApp : if defined, apply these kernel parameters for a (container) app
	// (and not for the host).
	ForApp ContainerApp
	// NetIf : network interface for which parameters are applied.
	NetIf genericitems.NetworkIf
	// EnableDAD : enable duplicate address detection (IPv6).
	EnableDAD bool
	// EnableARPNotify : generate gratuitous arp requests when device is brought up
	// or hardware address changes
	EnableARPNotify bool
}

Sysctl : item representing kernel parameters set for a network interface using sysctl.

func (Sysctl) Dependencies 

func (s Sysctl) Dependencies() (deps []dg.Dependency)

Dependencies returns the target interface as the only dependency.

func (Sysctl) Equal 

func (s Sysctl) Equal(other dg.Item) bool

Equal compares sysctl settings.

func (Sysctl) External 

func (s Sysctl) External() bool

External returns false.

func (Sysctl) Label 

func (s Sysctl) Label() string

Label is not defined.

func (Sysctl) Name 

func (s Sysctl) Name() string

Name of the item instance.

func (Sysctl) String 

func (s Sysctl) String() string

String prints sysctl settings.

func (Sysctl) Type 

func (s Sysctl) Type() string

Type of the item.

type SysctlConfigurator 

type SysctlConfigurator struct {
	Log *base.LogObject
}

SysctlConfigurator implements Configurator for sysctl settings.

func (*SysctlConfigurator) Create 

func (c *SysctlConfigurator) Create(ctx context.Context, item dg.Item) error

Create applies sysctl settings.

func (*SysctlConfigurator) Delete 

func (c *SysctlConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete sets default sysctl settings.

func (*SysctlConfigurator) Modify 

func (c *SysctlConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) error

Modify updates sysctl settings.

func (*SysctlConfigurator) NeedsRecreate 

func (c *SysctlConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns false - Modify is able to apply any change.

type TrunkPort 

type TrunkPort struct {
	AllVIDs bool // Allow all valid VIDs: <2,4093>
	VIDs    []uint16
}

TrunkPort : port carries tagged traffic from multiple VLANs.

type VIF 

type VIF struct {
	// HostIfName : name of the interface inside the network stack on the host side.
	HostIfName string
	// NetAdapterName is the logical name for this interface received from the controller
	// in NetworkAdapter.Name.
	// Unique in the scope of the application.
	NetAdapterName string
	// Variant : VIF should be one of the supported variants.
	Variant VIFVariant
}

VIF : virtual interface connecting an application to a network instance. It can be either an external item created by the hypervisor, or an internal item configured by zedrouter.

func (VIF) Dependencies 

func (v VIF) Dependencies() (deps []dg.Dependency)

Dependencies returns no dependencies.

func (VIF) Equal 

func (v VIF) Equal(other dg.Item) bool

Equal compares two VIF instances.

func (VIF) External 

func (v VIF) External() bool

External returns true if VIF is created by the hypervisor.

func (VIF) GetAssignedIPs 

func (v VIF) GetAssignedIPs() []*net.IPNet

GetAssignedIPs returns IP addresses assigned (by zedrouter) to the VIF interface.

func (VIF) Label 

func (v VIF) Label() string

Label returns the logical label from NetworkAdapter.

func (VIF) Name 

func (v VIF) Name() string

Name returns the physical interface name on the host side.

func (VIF) String 

func (v VIF) String() string

String describes VIF.

func (VIF) Type 

func (v VIF) Type() string

Type of the item.

type VIFConfigurator 

type VIFConfigurator struct {
	Log *base.LogObject
}

VIFConfigurator implements Configurator interface for Veth VIF.

func (*VIFConfigurator) Create 

func (c *VIFConfigurator) Create(ctx context.Context, item dg.Item) error

Create adds new veth.

func (*VIFConfigurator) Delete 

func (c *VIFConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes veth. Should be enough to just remove one side.

func (*VIFConfigurator) Modify 

func (c *VIFConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify allows to change assigned IP addresses.

func (*VIFConfigurator) NeedsRecreate 

func (c *VIFConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true when anything other that Veth IPs change.

type VIFReference 

type VIFReference struct {
	ItemName string
	IfName   string
}

VIFReference : VIF used as the output interface for route.

type VIFVariant 

type VIFVariant struct {
	// Enable if VIF is created by an external process (e.g. hypervisor).
	External bool
	// Veth configured by zedrouter between the host and the app (container).
	Veth Veth
}

VIFVariant is like union, only one option should have non-zero value.

type VLANBridge 

type VLANBridge struct {
	// BridgeIfName : interface name of the bridge.
	BridgeIfName string
	// EnableVLANFiltering : drop packet if it belongs to a VLAN which is not enabled
	// on the input bridge port (using VLANPort config item).
	EnableVLANFiltering bool
}

VLANBridge : VLAN configuration for a Linux bridge.

func (VLANBridge) Dependencies 

func (v VLANBridge) Dependencies() (deps []dg.Dependency)

Dependencies returns the bridge as the only dependency.

func (VLANBridge) Equal 

func (v VLANBridge) Equal(other dg.Item) bool

Equal compares two VLANBridge instances.

func (VLANBridge) External 

func (v VLANBridge) External() bool

External returns false.

func (VLANBridge) Label 

func (v VLANBridge) Label() string

Label for VLANBridge.

func (VLANBridge) Name 

func (v VLANBridge) Name() string

Name returns the interface name of the bridge.

func (VLANBridge) String 

func (v VLANBridge) String() string

String describes VLANBridge.

func (VLANBridge) Type 

func (v VLANBridge) Type() string

Type of the item.

type VLANBridgeConfigurator 

type VLANBridgeConfigurator struct {
	Log            *base.LogObject
	NetworkMonitor netmonitor.NetworkMonitor
}

VLANBridgeConfigurator implements Configurator interface (libs/reconciler) for VLAN configuration applied to a Linux bridge.

func (*VLANBridgeConfigurator) Create 

func (c *VLANBridgeConfigurator) Create(ctx context.Context, item dg.Item) error

Create applies VLAN configuration to a bridge.

func (*VLANBridgeConfigurator) Delete 

func (c *VLANBridgeConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes VLAN configuration from a bridge.

func (*VLANBridgeConfigurator) Modify 

func (c *VLANBridgeConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*VLANBridgeConfigurator) NeedsRecreate 

func (c *VLANBridgeConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true - Modify is not implemented.

type VLANConfig 

type VLANConfig struct {
	AccessPort *AccessPort
	TrunkPort  *TrunkPort
}

VLANConfig : VLAN configuration to apply on the bridge port. Port is either configured as a trunk or as an access port (use this struct as union).

type VLANPort 

type VLANPort struct {
	// BridgeIfName : interface name of the bridge.
	BridgeIfName string
	// PortIfName : interface name of the bridge port.
	PortIfName string
	// VLANConfig : VLAN configuration to apply on the bridged interface.
	VLANConfig VLANConfig
}

VLANPort : VLAN configuration for a Linux bridge port.

func (VLANPort) Dependencies 

func (v VLANPort) Dependencies() (deps []dg.Dependency)

Dependencies returns the (VLAN-enabled) bridge and the port as the dependencies.

func (VLANPort) Equal 

func (v VLANPort) Equal(other dg.Item) bool

Equal compares two VLANPort instances.

func (VLANPort) External 

func (v VLANPort) External() bool

External returns false.

func (VLANPort) Label 

func (v VLANPort) Label() string

Label for VLANPort.

func (VLANPort) Name 

func (v VLANPort) Name() string

Name returns the interface name of the bridged port (there can be at most one instance of VLANPort associated with a given bridged port).

func (VLANPort) String 

func (v VLANPort) String() string

String describes VLANPort.

func (VLANPort) Type 

func (v VLANPort) Type() string

Type of the item.

type VLANPortConfigurator 

type VLANPortConfigurator struct {
	Log            *base.LogObject
	NetworkMonitor netmonitor.NetworkMonitor
}

VLANPortConfigurator implements Configurator interface (libs/reconciler) for VLAN configuration applied to a Linux bridge port.

func (*VLANPortConfigurator) Create 

func (c *VLANPortConfigurator) Create(ctx context.Context, item dg.Item) error

Create applies VLAN configuration to a bridge port.

func (*VLANPortConfigurator) Delete 

func (c *VLANPortConfigurator) Delete(ctx context.Context, item dg.Item) error

Delete removes VLAN configuration from a bridge port.

func (*VLANPortConfigurator) Modify 

func (c *VLANPortConfigurator) Modify(ctx context.Context, oldItem, newItem dg.Item) (err error)

Modify is not implemented.

func (*VLANPortConfigurator) NeedsRecreate 

func (c *VLANPortConfigurator) NeedsRecreate(oldItem, newItem dg.Item) (recreate bool)

NeedsRecreate returns true - Modify is not implemented.

type Veth 

type Veth struct {
	ForApp ContainerApp
	// AppIfName : name of the interface inside the network stack on the app side.
	AppIfName string
	// AppIfMAC : MAC address assigned to the Veth interface on the app side.
	AppIfMAC net.HardwareAddr
	// AppIPs : IP addresses assigned to Veth on the app side.
	AppIPs []*net.IPNet
}

Veth : virtual ethernet pair created between the host and the (container) app network namespace.

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