1 files changed, 135 insertions, 82 deletions

diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go
index dd931f88c..f9d5e0085 100644
--- a/pkg/tcpip/transport/tcp/endpoint.go
+++ b/pkg/tcpip/transport/tcp/endpoint.go
@@ -15,6 +15,7 @@
 package tcp
 
 import (
+	"encoding/binary"
 	"fmt"
 	"math"
 	"strings"
@@ -26,6 +27,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sleep"
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
+	"gvisor.dev/gvisor/pkg/tcpip/hash/jenkins"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
 	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/seqnum"
@@ -280,6 +282,9 @@ type endpoint struct {
 	// reusePort is set to true if SO_REUSEPORT is enabled.
 	reusePort bool
 
+	// bindToDevice is set to the NIC on which to bind or disabled if 0.
+	bindToDevice tcpip.NICID
+
 	// delay enables Nagle's algorithm.
 	//
 	// delay is a boolean (0 is false) and must be accessed atomically.
@@ -564,11 +569,11 @@ func (e *endpoint) Close() {
 	// in Listen() when trying to register.
 	if e.state == StateListen && e.isPortReserved {
 		if e.isRegistered {
-			e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e)
+			e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e, e.bindToDevice)
 			e.isRegistered = false
 		}
 
-		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.id.LocalAddress, e.id.LocalPort)
+		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.id.LocalAddress, e.id.LocalPort, e.bindToDevice)
 		e.isPortReserved = false
 	}
 
@@ -625,12 +630,12 @@ func (e *endpoint) cleanupLocked() {
 	e.workerCleanup = false
 
 	if e.isRegistered {
-		e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e)
+		e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e, e.bindToDevice)
 		e.isRegistered = false
 	}
 
 	if e.isPortReserved {
-		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.id.LocalAddress, e.id.LocalPort)
+		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.id.LocalAddress, e.id.LocalPort, e.bindToDevice)
 		e.isPortReserved = false
 	}
 
@@ -952,62 +957,9 @@ func (e *endpoint) zeroReceiveWindow(scale uint8) bool {
 	return ((e.rcvBufSize - e.rcvBufUsed) >> scale) == 0
 }
 
-// SetSockOpt sets a socket option.
-func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error {
-	switch v := opt.(type) {
-	case tcpip.DelayOption:
-		if v == 0 {
-			atomic.StoreUint32(&e.delay, 0)
-
-			// Handle delayed data.
-			e.sndWaker.Assert()
-		} else {
-			atomic.StoreUint32(&e.delay, 1)
-		}
-		return nil
-
-	case tcpip.CorkOption:
-		if v == 0 {
-			atomic.StoreUint32(&e.cork, 0)
-
-			// Handle the corked data.
-			e.sndWaker.Assert()
-		} else {
-			atomic.StoreUint32(&e.cork, 1)
-		}
-		return nil
-
-	case tcpip.ReuseAddressOption:
-		e.mu.Lock()
-		e.reuseAddr = v != 0
-		e.mu.Unlock()
-		return nil
-
-	case tcpip.ReusePortOption:
-		e.mu.Lock()
-		e.reusePort = v != 0
-		e.mu.Unlock()
-		return nil
-
-	case tcpip.QuickAckOption:
-		if v == 0 {
-			atomic.StoreUint32(&e.slowAck, 1)
-		} else {
-			atomic.StoreUint32(&e.slowAck, 0)
-		}
-		return nil
-
-	case tcpip.MaxSegOption:
-		userMSS := v
-		if userMSS < header.TCPMinimumMSS || userMSS > header.TCPMaximumMSS {
-			return tcpip.ErrInvalidOptionValue
-		}
-		e.mu.Lock()
-		e.userMSS = int(userMSS)
-		e.mu.Unlock()
-		e.notifyProtocolGoroutine(notifyMSSChanged)
-		return nil
-
+// SetSockOptInt sets a socket option.
+func (e *endpoint) SetSockOptInt(opt tcpip.SockOpt, v int) *tcpip.Error {
+	switch opt {
 	case tcpip.ReceiveBufferSizeOption:
 		// Make sure the receive buffer size is within the min and max
 		// allowed.
@@ -1071,6 +1023,82 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error {
 		e.sndBufMu.Unlock()
 		return nil
 
+	default:
+		return nil
+	}
+}
+
+// SetSockOpt sets a socket option.
+func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error {
+	switch v := opt.(type) {
+	case tcpip.DelayOption:
+		if v == 0 {
+			atomic.StoreUint32(&e.delay, 0)
+
+			// Handle delayed data.
+			e.sndWaker.Assert()
+		} else {
+			atomic.StoreUint32(&e.delay, 1)
+		}
+		return nil
+
+	case tcpip.CorkOption:
+		if v == 0 {
+			atomic.StoreUint32(&e.cork, 0)
+
+			// Handle the corked data.
+			e.sndWaker.Assert()
+		} else {
+			atomic.StoreUint32(&e.cork, 1)
+		}
+		return nil
+
+	case tcpip.ReuseAddressOption:
+		e.mu.Lock()
+		e.reuseAddr = v != 0
+		e.mu.Unlock()
+		return nil
+
+	case tcpip.ReusePortOption:
+		e.mu.Lock()
+		e.reusePort = v != 0
+		e.mu.Unlock()
+		return nil
+
+	case tcpip.BindToDeviceOption:
+		e.mu.Lock()
+		defer e.mu.Unlock()
+		if v == "" {
+			e.bindToDevice = 0
+			return nil
+		}
+		for nicid, nic := range e.stack.NICInfo() {
+			if nic.Name == string(v) {
+				e.bindToDevice = nicid
+				return nil
+			}
+		}
+		return tcpip.ErrUnknownDevice
+
+	case tcpip.QuickAckOption:
+		if v == 0 {
+			atomic.StoreUint32(&e.slowAck, 1)
+		} else {
+			atomic.StoreUint32(&e.slowAck, 0)
+		}
+		return nil
+
+	case tcpip.MaxSegOption:
+		userMSS := v
+		if userMSS < header.TCPMinimumMSS || userMSS > header.TCPMaximumMSS {
+			return tcpip.ErrInvalidOptionValue
+		}
+		e.mu.Lock()
+		e.userMSS = int(userMSS)
+		e.mu.Unlock()
+		e.notifyProtocolGoroutine(notifyMSSChanged)
+		return nil
+
 	case tcpip.V6OnlyOption:
 		// We only recognize this option on v6 endpoints.
 		if e.netProto != header.IPv6ProtocolNumber {
@@ -1182,6 +1210,18 @@ func (e *endpoint) GetSockOptInt(opt tcpip.SockOpt) (int, *tcpip.Error) {
 	switch opt {
 	case tcpip.ReceiveQueueSizeOption:
 		return e.readyReceiveSize()
+	case tcpip.SendBufferSizeOption:
+		e.sndBufMu.Lock()
+		v := e.sndBufSize
+		e.sndBufMu.Unlock()
+		return v, nil
+
+	case tcpip.ReceiveBufferSizeOption:
+		e.rcvListMu.Lock()
+		v := e.rcvBufSize
+		e.rcvListMu.Unlock()
+		return v, nil
+
 	}
 	return -1, tcpip.ErrUnknownProtocolOption
 }
@@ -1204,18 +1244,6 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error {
 		*o = header.TCPDefaultMSS
 		return nil
 
-	case *tcpip.SendBufferSizeOption:
-		e.sndBufMu.Lock()
-		*o = tcpip.SendBufferSizeOption(e.sndBufSize)
-		e.sndBufMu.Unlock()
-		return nil
-
-	case *tcpip.ReceiveBufferSizeOption:
-		e.rcvListMu.Lock()
-		*o = tcpip.ReceiveBufferSizeOption(e.rcvBufSize)
-		e.rcvListMu.Unlock()
-		return nil
-
 	case *tcpip.DelayOption:
 		*o = 0
 		if v := atomic.LoadUint32(&e.delay); v != 0 {
@@ -1252,6 +1280,16 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error {
 		}
 		return nil
 
+	case *tcpip.BindToDeviceOption:
+		e.mu.RLock()
+		defer e.mu.RUnlock()
+		if nic, ok := e.stack.NICInfo()[e.bindToDevice]; ok {
+			*o = tcpip.BindToDeviceOption(nic.Name)
+			return nil
+		}
+		*o = ""
+		return nil
+
 	case *tcpip.QuickAckOption:
 		*o = 1
 		if v := atomic.LoadUint32(&e.slowAck); v != 0 {
@@ -1458,7 +1496,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) (er
 
 	if e.id.LocalPort != 0 {
 		// The endpoint is bound to a port, attempt to register it.
-		err := e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, e.id, e, e.reusePort)
+		err := e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, e.id, e, e.reusePort, e.bindToDevice)
 		if err != nil {
 			return err
 		}
@@ -1468,17 +1506,32 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) (er
 		// address/port for both local and remote (otherwise this
 		// endpoint would be trying to connect to itself).
 		sameAddr := e.id.LocalAddress == e.id.RemoteAddress
-		if _, err := e.stack.PickEphemeralPort(func(p uint16) (bool, *tcpip.Error) {
+
+		// Calculate a port offset based on the destination IP/port and
+		// src IP to ensure that for a given tuple (srcIP, destIP,
+		// destPort) the offset used as a starting point is the same to
+		// ensure that we can cycle through the port space effectively.
+		h := jenkins.Sum32(e.stack.PortSeed())
+		h.Write([]byte(e.id.LocalAddress))
+		h.Write([]byte(e.id.RemoteAddress))
+		portBuf := make([]byte, 2)
+		binary.LittleEndian.PutUint16(portBuf, e.id.RemotePort)
+		h.Write(portBuf)
+		portOffset := h.Sum32()
+
+		if _, err := e.stack.PickEphemeralPortStable(portOffset, func(p uint16) (bool, *tcpip.Error) {
 			if sameAddr && p == e.id.RemotePort {
 				return false, nil
 			}
-			if !e.stack.IsPortAvailable(netProtos, ProtocolNumber, e.id.LocalAddress, p, false) {
+			// reusePort is false below because connect cannot reuse a port even if
+			// reusePort was set.
+			if !e.stack.IsPortAvailable(netProtos, ProtocolNumber, e.id.LocalAddress, p, false /* reusePort */, e.bindToDevice) {
 				return false, nil
 			}
 
 			id := e.id
 			id.LocalPort = p
-			switch e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, id, e, e.reusePort) {
+			switch e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, id, e, e.reusePort, e.bindToDevice) {
 			case nil:
 				e.id = id
 				return true, nil
@@ -1496,7 +1549,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) (er
 	// before Connect: in such a case we don't want to hold on to
 	// reservations anymore.
 	if e.isPortReserved {
-		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, origID.LocalAddress, origID.LocalPort)
+		e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, origID.LocalAddress, origID.LocalPort, e.bindToDevice)
 		e.isPortReserved = false
 	}
 
@@ -1640,7 +1693,7 @@ func (e *endpoint) Listen(backlog int) (err *tcpip.Error) {
 	}
 
 	// Register the endpoint.
-	if err := e.stack.RegisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e, e.reusePort); err != nil {
+	if err := e.stack.RegisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.id, e, e.reusePort, e.bindToDevice); err != nil {
 		return err
 	}
 
@@ -1721,7 +1774,7 @@ func (e *endpoint) Bind(addr tcpip.FullAddress) (err *tcpip.Error) {
 		}
 	}
 
-	port, err := e.stack.ReservePort(netProtos, ProtocolNumber, addr.Addr, addr.Port, e.reusePort)
+	port, err := e.stack.ReservePort(netProtos, ProtocolNumber, addr.Addr, addr.Port, e.reusePort, e.bindToDevice)
 	if err != nil {
 		return err
 	}
@@ -1731,16 +1784,16 @@ func (e *endpoint) Bind(addr tcpip.FullAddress) (err *tcpip.Error) {
 	e.id.LocalPort = port
 
 	// Any failures beyond this point must remove the port registration.
-	defer func() {
+	defer func(bindToDevice tcpip.NICID) {
 		if err != nil {
-			e.stack.ReleasePort(netProtos, ProtocolNumber, addr.Addr, port)
+			e.stack.ReleasePort(netProtos, ProtocolNumber, addr.Addr, port, bindToDevice)
 			e.isPortReserved = false
 			e.effectiveNetProtos = nil
 			e.id.LocalPort = 0
 			e.id.LocalAddress = ""
 			e.boundNICID = 0
 		}
-	}()
+	}(e.bindToDevice)
 
 	// If an address is specified, we must ensure that it's one of our
 	// local addresses.