1 files changed, 57 insertions, 1 deletions
diff --git a/pkg/tcpip/socketops.go b/pkg/tcpip/socketops.go
index dc37e61a4..a6c877158 100644
--- a/pkg/tcpip/socketops.go
+++ b/pkg/tcpip/socketops.go
@@ -58,6 +58,9 @@ type SocketOptionsHandler interface {
 	// changed. The handler is invoked with the new value for the socket send
 	// buffer size. It also returns the newly set value.
 	OnSetSendBufferSize(v int64) (newSz int64)
+
+	// OnSetReceiveBufferSize is invoked to set the SO_RCVBUFSIZE.
+	OnSetReceiveBufferSize(v, oldSz int64) (newSz int64)
 }
 
 // DefaultSocketOptionsHandler is an embeddable type that implements no-op
@@ -99,6 +102,11 @@ func (*DefaultSocketOptionsHandler) OnSetSendBufferSize(v int64) (newSz int64) {
 	return v
 }
 
+// OnSetReceiveBufferSize implements SocketOptionsHandler.OnSetReceiveBufferSize.
+func (*DefaultSocketOptionsHandler) OnSetReceiveBufferSize(v, oldSz int64) (newSz int64) {
+	return v
+}
+
 // StackHandler holds methods to access the stack options. These must be
 // implemented by the stack.
 type StackHandler interface {
@@ -207,6 +215,14 @@ type SocketOptions struct {
 	// sendBufferSize determines the send buffer size for this socket.
 	sendBufferSize int64
 
+	// getReceiveBufferLimits provides the handler to get the min, default and
+	// max size for receive buffer. It is initialized at the creation time and
+	// will not change.
+	getReceiveBufferLimits GetReceiveBufferLimits `state:"manual"`
+
+	// receiveBufferSize determines the receive buffer size for this socket.
+	receiveBufferSize int64
+
 	// mu protects the access to the below fields.
 	mu sync.Mutex `state:"nosave"`
 
@@ -217,10 +233,11 @@ type SocketOptions struct {
 
 // InitHandler initializes the handler. This must be called before using the
 // socket options utility.
-func (so *SocketOptions) InitHandler(handler SocketOptionsHandler, stack StackHandler, getSendBufferLimits GetSendBufferLimits) {
+func (so *SocketOptions) InitHandler(handler SocketOptionsHandler, stack StackHandler, getSendBufferLimits GetSendBufferLimits, getReceiveBufferLimits GetReceiveBufferLimits) {
 	so.handler = handler
 	so.stackHandler = stack
 	so.getSendBufferLimits = getSendBufferLimits
+	so.getReceiveBufferLimits = getReceiveBufferLimits
 }
 
 func storeAtomicBool(addr *uint32, v bool) {
@@ -632,3 +649,42 @@ func (so *SocketOptions) SetSendBufferSize(sendBufferSize int64, notify bool) {
 	newSz := so.handler.OnSetSendBufferSize(v)
 	atomic.StoreInt64(&so.sendBufferSize, newSz)
 }
+
+// GetReceiveBufferSize gets value for SO_RCVBUF option.
+func (so *SocketOptions) GetReceiveBufferSize() int64 {
+	return atomic.LoadInt64(&so.receiveBufferSize)
+}
+
+// SetReceiveBufferSize sets value for SO_RCVBUF option.
+func (so *SocketOptions) SetReceiveBufferSize(receiveBufferSize int64, notify bool) {
+	if !notify {
+		atomic.StoreInt64(&so.receiveBufferSize, receiveBufferSize)
+		return
+	}
+
+	// Make sure the send buffer size is within the min and max
+	// allowed.
+	v := receiveBufferSize
+	ss := so.getReceiveBufferLimits(so.stackHandler)
+	min := int64(ss.Min)
+	max := int64(ss.Max)
+	// Validate the send buffer size with min and max values.
+	if v > max {
+		v = max
+	}
+
+	// Multiply it by factor of 2.
+	if v < math.MaxInt32/PacketOverheadFactor {
+		v *= PacketOverheadFactor
+		if v < min {
+			v = min
+		}
+	} else {
+		v = math.MaxInt32
+	}
+
+	oldSz := atomic.LoadInt64(&so.receiveBufferSize)
+	// Notify endpoint about change in buffer size.
+	newSz := so.handler.OnSetReceiveBufferSize(v, oldSz)
+	atomic.StoreInt64(&so.receiveBufferSize, newSz)
+}