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Diffstat (limited to 'pkg/tcpip/stack/stack.go')
-rw-r--r--pkg/tcpip/stack/stack.go250
1 files changed, 189 insertions, 61 deletions
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index 0e88643a4..7057b110e 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -21,13 +21,13 @@ package stack
import (
"encoding/binary"
- "sync"
"sync/atomic"
"time"
"golang.org/x/time/rate"
"gvisor.dev/gvisor/pkg/rand"
"gvisor.dev/gvisor/pkg/sleep"
+ "gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/tcpip"
"gvisor.dev/gvisor/pkg/tcpip/buffer"
"gvisor.dev/gvisor/pkg/tcpip/header"
@@ -352,6 +352,38 @@ func (u *uniqueIDGenerator) UniqueID() uint64 {
return atomic.AddUint64((*uint64)(u), 1)
}
+// NICNameFromID is a function that returns a stable name for the specified NIC,
+// even if different NIC IDs are used to refer to the same NIC in different
+// program runs. It is used when generating opaque interface identifiers (IIDs).
+// If the NIC was created with a name, it will be passed to NICNameFromID.
+//
+// NICNameFromID SHOULD return unique NIC names so unique opaque IIDs are
+// generated for the same prefix on differnt NICs.
+type NICNameFromID func(tcpip.NICID, string) string
+
+// OpaqueInterfaceIdentifierOptions holds the options related to the generation
+// of opaque interface indentifiers (IIDs) as defined by RFC 7217.
+type OpaqueInterfaceIdentifierOptions struct {
+ // NICNameFromID is a function that returns a stable name for a specified NIC,
+ // even if the NIC ID changes over time.
+ //
+ // Must be specified to generate the opaque IID.
+ NICNameFromID NICNameFromID
+
+ // SecretKey is a pseudo-random number used as the secret key when generating
+ // opaque IIDs as defined by RFC 7217. The key SHOULD be at least
+ // header.OpaqueIIDSecretKeyMinBytes bytes and MUST follow minimum randomness
+ // requirements for security as outlined by RFC 4086. SecretKey MUST NOT
+ // change between program runs, unless explicitly changed.
+ //
+ // OpaqueInterfaceIdentifierOptions takes ownership of SecretKey. SecretKey
+ // MUST NOT be modified after Stack is created.
+ //
+ // May be nil, but a nil value is highly discouraged to maintain
+ // some level of randomness between nodes.
+ SecretKey []byte
+}
+
// Stack is a networking stack, with all supported protocols, NICs, and route
// table.
type Stack struct {
@@ -391,7 +423,11 @@ type Stack struct {
// handleLocal allows non-loopback interfaces to loop packets.
handleLocal bool
- // tables are the iptables packet filtering and manipulation rules.
+ // tablesMu protects iptables.
+ tablesMu sync.RWMutex
+
+ // tables are the iptables packet filtering and manipulation rules. The are
+ // protected by tablesMu.`
tables iptables.IPTables
// resumableEndpoints is a list of endpoints that need to be resumed if the
@@ -412,8 +448,8 @@ type Stack struct {
ndpConfigs NDPConfigurations
// autoGenIPv6LinkLocal determines whether or not the stack will attempt
- // to auto-generate an IPv6 link-local address for newly enabled NICs.
- // See the AutoGenIPv6LinkLocal field of Options for more details.
+ // to auto-generate an IPv6 link-local address for newly enabled non-loopback
+ // NICs. See the AutoGenIPv6LinkLocal field of Options for more details.
autoGenIPv6LinkLocal bool
// ndpDisp is the NDP event dispatcher that is used to send the netstack
@@ -422,6 +458,10 @@ type Stack struct {
// uniqueIDGenerator is a generator of unique identifiers.
uniqueIDGenerator UniqueID
+
+ // opaqueIIDOpts hold the options for generating opaque interface identifiers
+ // (IIDs) as outlined by RFC 7217.
+ opaqueIIDOpts OpaqueInterfaceIdentifierOptions
}
// UniqueID is an abstract generator of unique identifiers.
@@ -460,13 +500,15 @@ type Options struct {
// before assigning an address to a NIC.
NDPConfigs NDPConfigurations
- // AutoGenIPv6LinkLocal determins whether or not the stack will attempt
- // to auto-generate an IPv6 link-local address for newly enabled NICs.
+ // AutoGenIPv6LinkLocal determines whether or not the stack will attempt to
+ // auto-generate an IPv6 link-local address for newly enabled non-loopback
+ // NICs.
+ //
// Note, setting this to true does not mean that a link-local address
- // will be assigned right away, or at all. If Duplicate Address
- // Detection is enabled, an address will only be assigned if it
- // successfully resolves. If it fails, no further attempt will be made
- // to auto-generate an IPv6 link-local address.
+ // will be assigned right away, or at all. If Duplicate Address Detection
+ // is enabled, an address will only be assigned if it successfully resolves.
+ // If it fails, no further attempt will be made to auto-generate an IPv6
+ // link-local address.
//
// The generated link-local address will follow RFC 4291 Appendix A
// guidelines.
@@ -479,6 +521,10 @@ type Options struct {
// RawFactory produces raw endpoints. Raw endpoints are enabled only if
// this is non-nil.
RawFactory RawFactory
+
+ // OpaqueIIDOpts hold the options for generating opaque interface identifiers
+ // (IIDs) as outlined by RFC 7217.
+ OpaqueIIDOpts OpaqueInterfaceIdentifierOptions
}
// TransportEndpointInfo holds useful information about a transport endpoint
@@ -505,6 +551,49 @@ type TransportEndpointInfo struct {
RegisterNICID tcpip.NICID
}
+// AddrNetProto unwraps the specified address if it is a V4-mapped V6 address
+// and returns the network protocol number to be used to communicate with the
+// specified address. It returns an error if the passed address is incompatible
+// with the receiver.
+func (e *TransportEndpointInfo) AddrNetProto(addr tcpip.FullAddress, v6only bool) (tcpip.FullAddress, tcpip.NetworkProtocolNumber, *tcpip.Error) {
+ netProto := e.NetProto
+ switch len(addr.Addr) {
+ case header.IPv4AddressSize:
+ netProto = header.IPv4ProtocolNumber
+ case header.IPv6AddressSize:
+ if header.IsV4MappedAddress(addr.Addr) {
+ netProto = header.IPv4ProtocolNumber
+ addr.Addr = addr.Addr[header.IPv6AddressSize-header.IPv4AddressSize:]
+ if addr.Addr == header.IPv4Any {
+ addr.Addr = ""
+ }
+ }
+ }
+
+ switch len(e.ID.LocalAddress) {
+ case header.IPv4AddressSize:
+ if len(addr.Addr) == header.IPv6AddressSize {
+ return tcpip.FullAddress{}, 0, tcpip.ErrInvalidEndpointState
+ }
+ case header.IPv6AddressSize:
+ if len(addr.Addr) == header.IPv4AddressSize {
+ return tcpip.FullAddress{}, 0, tcpip.ErrNetworkUnreachable
+ }
+ }
+
+ switch {
+ case netProto == e.NetProto:
+ case netProto == header.IPv4ProtocolNumber && e.NetProto == header.IPv6ProtocolNumber:
+ if v6only {
+ return tcpip.FullAddress{}, 0, tcpip.ErrNoRoute
+ }
+ default:
+ return tcpip.FullAddress{}, 0, tcpip.ErrInvalidEndpointState
+ }
+
+ return addr, netProto, nil
+}
+
// IsEndpointInfo is an empty method to implement the tcpip.EndpointInfo
// marker interface.
func (*TransportEndpointInfo) IsEndpointInfo() {}
@@ -549,6 +638,7 @@ func New(opts Options) *Stack {
autoGenIPv6LinkLocal: opts.AutoGenIPv6LinkLocal,
uniqueIDGenerator: opts.UniqueID,
ndpDisp: opts.NDPDisp,
+ opaqueIIDOpts: opts.OpaqueIIDOpts,
}
// Add specified network protocols.
@@ -662,11 +752,37 @@ func (s *Stack) Stats() tcpip.Stats {
}
// SetForwarding enables or disables the packet forwarding between NICs.
+//
+// When forwarding becomes enabled, any host-only state on all NICs will be
+// cleaned up and if IPv6 is enabled, NDP Router Solicitations will be started.
+// When forwarding becomes disabled and if IPv6 is enabled, NDP Router
+// Solicitations will be stopped.
func (s *Stack) SetForwarding(enable bool) {
// TODO(igudger, bgeffon): Expose via /proc/sys/net/ipv4/ip_forward.
s.mu.Lock()
+ defer s.mu.Unlock()
+
+ // If forwarding status didn't change, do nothing further.
+ if s.forwarding == enable {
+ return
+ }
+
s.forwarding = enable
- s.mu.Unlock()
+
+ // If this stack does not support IPv6, do nothing further.
+ if _, ok := s.networkProtocols[header.IPv6ProtocolNumber]; !ok {
+ return
+ }
+
+ if enable {
+ for _, nic := range s.nics {
+ nic.becomeIPv6Router()
+ }
+ } else {
+ for _, nic := range s.nics {
+ nic.becomeIPv6Host()
+ }
+ }
}
// Forwarding returns if the packet forwarding between NICs is enabled.
@@ -733,9 +849,30 @@ func (s *Stack) NewPacketEndpoint(cooked bool, netProto tcpip.NetworkProtocolNum
return s.rawFactory.NewPacketEndpoint(s, cooked, netProto, waiterQueue)
}
-// createNIC creates a NIC with the provided id and link-layer endpoint, and
-// optionally enable it.
-func (s *Stack) createNIC(id tcpip.NICID, name string, ep LinkEndpoint, enabled, loopback bool) *tcpip.Error {
+// NICContext is an opaque pointer used to store client-supplied NIC metadata.
+type NICContext interface{}
+
+// NICOptions specifies the configuration of a NIC as it is being created.
+// The zero value creates an enabled, unnamed NIC.
+type NICOptions struct {
+ // Name specifies the name of the NIC.
+ Name string
+
+ // Disabled specifies whether to avoid calling Attach on the passed
+ // LinkEndpoint.
+ Disabled bool
+
+ // Context specifies user-defined data that will be returned in stack.NICInfo
+ // for the NIC. Clients of this library can use it to add metadata that
+ // should be tracked alongside a NIC, to avoid having to keep a
+ // map[tcpip.NICID]metadata mirroring stack.Stack's nic map.
+ Context NICContext
+}
+
+// CreateNICWithOptions creates a NIC with the provided id, LinkEndpoint, and
+// NICOptions. See the documentation on type NICOptions for details on how
+// NICs can be configured.
+func (s *Stack) CreateNICWithOptions(id tcpip.NICID, ep LinkEndpoint, opts NICOptions) *tcpip.Error {
s.mu.Lock()
defer s.mu.Unlock()
@@ -744,44 +881,20 @@ func (s *Stack) createNIC(id tcpip.NICID, name string, ep LinkEndpoint, enabled,
return tcpip.ErrDuplicateNICID
}
- n := newNIC(s, id, name, ep, loopback)
+ n := newNIC(s, id, opts.Name, ep, opts.Context)
s.nics[id] = n
- if enabled {
+ if !opts.Disabled {
return n.enable()
}
return nil
}
-// CreateNIC creates a NIC with the provided id and link-layer endpoint.
+// CreateNIC creates a NIC with the provided id and LinkEndpoint and calls
+// `LinkEndpoint.Attach` to start delivering packets to it.
func (s *Stack) CreateNIC(id tcpip.NICID, ep LinkEndpoint) *tcpip.Error {
- return s.createNIC(id, "", ep, true, false)
-}
-
-// CreateNamedNIC creates a NIC with the provided id and link-layer endpoint,
-// and a human-readable name.
-func (s *Stack) CreateNamedNIC(id tcpip.NICID, name string, ep LinkEndpoint) *tcpip.Error {
- return s.createNIC(id, name, ep, true, false)
-}
-
-// CreateNamedLoopbackNIC creates a NIC with the provided id and link-layer
-// endpoint, and a human-readable name.
-func (s *Stack) CreateNamedLoopbackNIC(id tcpip.NICID, name string, ep LinkEndpoint) *tcpip.Error {
- return s.createNIC(id, name, ep, true, true)
-}
-
-// CreateDisabledNIC creates a NIC with the provided id and link-layer endpoint,
-// but leave it disable. Stack.EnableNIC must be called before the link-layer
-// endpoint starts delivering packets to it.
-func (s *Stack) CreateDisabledNIC(id tcpip.NICID, ep LinkEndpoint) *tcpip.Error {
- return s.createNIC(id, "", ep, false, false)
-}
-
-// CreateDisabledNamedNIC is a combination of CreateNamedNIC and
-// CreateDisabledNIC.
-func (s *Stack) CreateDisabledNamedNIC(id tcpip.NICID, name string, ep LinkEndpoint) *tcpip.Error {
- return s.createNIC(id, name, ep, false, false)
+ return s.CreateNICWithOptions(id, ep, NICOptions{})
}
// EnableNIC enables the given NIC so that the link-layer endpoint can start
@@ -809,7 +922,7 @@ func (s *Stack) CheckNIC(id tcpip.NICID) bool {
return false
}
-// NICSubnets returns a map of NICIDs to their associated subnets.
+// NICAddressRanges returns a map of NICIDs to their associated subnets.
func (s *Stack) NICAddressRanges() map[tcpip.NICID][]tcpip.Subnet {
s.mu.RLock()
defer s.mu.RUnlock()
@@ -835,6 +948,18 @@ type NICInfo struct {
MTU uint32
Stats NICStats
+
+ // Context is user-supplied data optionally supplied in CreateNICWithOptions.
+ // See type NICOptions for more details.
+ Context NICContext
+}
+
+// HasNIC returns true if the NICID is defined in the stack.
+func (s *Stack) HasNIC(id tcpip.NICID) bool {
+ s.mu.RLock()
+ _, ok := s.nics[id]
+ s.mu.RUnlock()
+ return ok
}
// NICInfo returns a map of NICIDs to their associated information.
@@ -848,7 +973,7 @@ func (s *Stack) NICInfo() map[tcpip.NICID]NICInfo {
Up: true, // Netstack interfaces are always up.
Running: nic.linkEP.IsAttached(),
Promiscuous: nic.isPromiscuousMode(),
- Loopback: nic.linkEP.Capabilities()&CapabilityLoopback != 0,
+ Loopback: nic.isLoopback(),
}
nics[id] = NICInfo{
Name: nic.name,
@@ -857,6 +982,7 @@ func (s *Stack) NICInfo() map[tcpip.NICID]NICInfo {
Flags: flags,
MTU: nic.linkEP.MTU(),
Stats: nic.stats,
+ Context: nic.context,
}
}
return nics
@@ -973,9 +1099,11 @@ func (s *Stack) AllAddresses() map[tcpip.NICID][]tcpip.ProtocolAddress {
return nics
}
-// GetMainNICAddress returns the first primary address and prefix for the given
-// NIC and protocol. Returns an error if the NIC doesn't exist and an empty
-// value if the NIC doesn't have a primary address for the given protocol.
+// GetMainNICAddress returns the first non-deprecated primary address and prefix
+// for the given NIC and protocol. If no non-deprecated primary address exists,
+// a deprecated primary address and prefix will be returned. Returns an error if
+// the NIC doesn't exist and an empty value if the NIC doesn't have a primary
+// address for the given protocol.
func (s *Stack) GetMainNICAddress(id tcpip.NICID, protocol tcpip.NetworkProtocolNumber) (tcpip.AddressWithPrefix, *tcpip.Error) {
s.mu.RLock()
defer s.mu.RUnlock()
@@ -985,17 +1113,12 @@ func (s *Stack) GetMainNICAddress(id tcpip.NICID, protocol tcpip.NetworkProtocol
return tcpip.AddressWithPrefix{}, tcpip.ErrUnknownNICID
}
- for _, a := range nic.PrimaryAddresses() {
- if a.Protocol == protocol {
- return a.AddressWithPrefix, nil
- }
- }
- return tcpip.AddressWithPrefix{}, nil
+ return nic.primaryAddress(protocol), nil
}
-func (s *Stack) getRefEP(nic *NIC, localAddr tcpip.Address, netProto tcpip.NetworkProtocolNumber) (ref *referencedNetworkEndpoint) {
+func (s *Stack) getRefEP(nic *NIC, localAddr, remoteAddr tcpip.Address, netProto tcpip.NetworkProtocolNumber) (ref *referencedNetworkEndpoint) {
if len(localAddr) == 0 {
- return nic.primaryEndpoint(netProto)
+ return nic.primaryEndpoint(netProto, remoteAddr)
}
return nic.findEndpoint(netProto, localAddr, CanBePrimaryEndpoint)
}
@@ -1011,8 +1134,8 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n
needRoute := !(isBroadcast || isMulticast || header.IsV6LinkLocalAddress(remoteAddr))
if id != 0 && !needRoute {
if nic, ok := s.nics[id]; ok {
- if ref := s.getRefEP(nic, localAddr, netProto); ref != nil {
- return makeRoute(netProto, ref.ep.ID().LocalAddress, remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.loopback, multicastLoop && !nic.loopback), nil
+ if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil {
+ return makeRoute(netProto, ref.ep.ID().LocalAddress, remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.isLoopback(), multicastLoop && !nic.isLoopback()), nil
}
}
} else {
@@ -1021,14 +1144,14 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n
continue
}
if nic, ok := s.nics[route.NIC]; ok {
- if ref := s.getRefEP(nic, localAddr, netProto); ref != nil {
+ if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil {
if len(remoteAddr) == 0 {
// If no remote address was provided, then the route
// provided will refer to the link local address.
remoteAddr = ref.ep.ID().LocalAddress
}
- r := makeRoute(netProto, ref.ep.ID().LocalAddress, remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.loopback, multicastLoop && !nic.loopback)
+ r := makeRoute(netProto, ref.ep.ID().LocalAddress, remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.isLoopback(), multicastLoop && !nic.isLoopback())
if needRoute {
r.NextHop = route.Gateway
}
@@ -1475,12 +1598,17 @@ func (s *Stack) LeaveGroup(protocol tcpip.NetworkProtocolNumber, nicID tcpip.NIC
// IPTables returns the stack's iptables.
func (s *Stack) IPTables() iptables.IPTables {
- return s.tables
+ s.tablesMu.RLock()
+ t := s.tables
+ s.tablesMu.RUnlock()
+ return t
}
// SetIPTables sets the stack's iptables.
func (s *Stack) SetIPTables(ipt iptables.IPTables) {
+ s.tablesMu.Lock()
s.tables = ipt
+ s.tablesMu.Unlock()
}
// ICMPLimit returns the maximum number of ICMP messages that can be sent