Plumbing for iptables sockopts.

PiperOrigin-RevId: 261413396

16 files changed, 74 insertions, 10 deletions

diff --git a/pkg/tcpip/BUILD b/pkg/tcpip/BUILD
index 047f8329a..df37c7d5a 100644
--- a/pkg/tcpip/BUILD
+++ b/pkg/tcpip/BUILD
@@ -12,6 +12,7 @@ go_library(
     visibility = ["//visibility:public"],
     deps = [
         "//pkg/tcpip/buffer",
+        "//pkg/tcpip/iptables",
         "//pkg/waiter",
     ],
 )
diff --git a/pkg/tcpip/iptables/BUILD b/pkg/tcpip/iptables/BUILD
index fc9abbb55..3fc14bacd 100644
--- a/pkg/tcpip/iptables/BUILD
+++ b/pkg/tcpip/iptables/BUILD
@@ -11,8 +11,5 @@ go_library(
     ],
     importpath = "gvisor.dev/gvisor/pkg/tcpip/iptables",
     visibility = ["//visibility:public"],
-    deps = [
-        "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
-    ],
+    deps = ["//pkg/tcpip/buffer"],
 )
diff --git a/pkg/tcpip/iptables/iptables.go b/pkg/tcpip/iptables/iptables.go
index f1e1d1fad..68c68d4aa 100644
--- a/pkg/tcpip/iptables/iptables.go
+++ b/pkg/tcpip/iptables/iptables.go
@@ -32,8 +32,8 @@ const (
 
 // DefaultTables returns a default set of tables. Each chain is set to accept
 // all packets.
-func DefaultTables() *IPTables {
-	return &IPTables{
+func DefaultTables() IPTables {
+	return IPTables{
 		Tables: map[string]Table{
 			tablenameNat: Table{
 				BuiltinChains: map[Hook]Chain{
diff --git a/pkg/tcpip/iptables/types.go b/pkg/tcpip/iptables/types.go
index 600bd9a10..42a79ef9f 100644
--- a/pkg/tcpip/iptables/types.go
+++ b/pkg/tcpip/iptables/types.go
@@ -15,7 +15,6 @@
 package iptables
 
 import (
-	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 )
 
@@ -128,15 +127,29 @@ type Table struct {
 	// UserChains, and its purpose is to make looking up tables by name
 	// fast.
 	Chains map[string]*Chain
+
+	// Metadata holds information about the Table that is useful to users
+	// of IPTables, but not to the netstack IPTables code itself.
+	metadata interface{}
 }
 
 // ValidHooks returns a bitmap of the builtin hooks for the given table.
-func (table *Table) ValidHooks() (uint32, *tcpip.Error) {
+func (table *Table) ValidHooks() uint32 {
 	hooks := uint32(0)
 	for hook, _ := range table.BuiltinChains {
 		hooks |= 1 << hook
 	}
-	return hooks, nil
+	return hooks
+}
+
+// Metadata returns the metadata object stored in table.
+func (table *Table) Metadata() interface{} {
+	return table.metadata
+}
+
+// SetMetadata sets the metadata object stored in table.
+func (table *Table) SetMetadata(metadata interface{}) {
+	table.metadata = metadata
 }
 
 // A Chain defines a list of rules for packet processing. When a packet
diff --git a/pkg/tcpip/stack/BUILD b/pkg/tcpip/stack/BUILD
index 28d11c797..9986b4be3 100644
--- a/pkg/tcpip/stack/BUILD
+++ b/pkg/tcpip/stack/BUILD
@@ -24,6 +24,7 @@ go_library(
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/hash/jenkins",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/ports",
         "//pkg/tcpip/seqnum",
         "//pkg/waiter",
@@ -42,6 +43,7 @@ go_test(
         "//pkg/tcpip",
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/link/channel",
         "//pkg/tcpip/link/loopback",
         "//pkg/waiter",
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index 6156c3f46..78beb0dae 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -32,6 +32,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/ports"
 	"gvisor.dev/gvisor/pkg/tcpip/seqnum"
 	"gvisor.dev/gvisor/pkg/waiter"
@@ -372,6 +373,9 @@ type Stack struct {
 
 	// handleLocal allows non-loopback interfaces to loop packets.
 	handleLocal bool
+
+	// tables are the iptables packet filtering and manipulation rules.
+	tables iptables.IPTables
 }
 
 // Options contains optional Stack configuration.
@@ -1166,3 +1170,13 @@ func (s *Stack) LeaveGroup(protocol tcpip.NetworkProtocolNumber, nicID tcpip.NIC
 	}
 	return tcpip.ErrUnknownNICID
 }
+
+// IPTables returns the stack's iptables.
+func (s *Stack) IPTables() iptables.IPTables {
+	return s.tables
+}
+
+// SetIPTables sets the stack's iptables.
+func (s *Stack) SetIPTables(ipt iptables.IPTables) {
+	s.tables = ipt
+}
diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go
index b418db046..8652d7814 100644
--- a/pkg/tcpip/stack/transport_test.go
+++ b/pkg/tcpip/stack/transport_test.go
@@ -19,6 +19,7 @@ import (
 
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/link/channel"
 	"gvisor.dev/gvisor/pkg/tcpip/link/loopback"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
@@ -200,6 +201,10 @@ func (f *fakeTransportEndpoint) State() uint32 {
 func (f *fakeTransportEndpoint) ModerateRecvBuf(copied int) {
 }
 
+func (f *fakeTransportEndpoint) IPTables() (iptables.IPTables, error) {
+	return iptables.IPTables{}, nil
+}
+
 type fakeTransportGoodOption bool
 
 type fakeTransportBadOption bool
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 4208c0303..0df9f6d93 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -39,6 +39,7 @@ import (
 	"time"
 
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
 
@@ -403,6 +404,9 @@ type Endpoint interface {
 	//
 	// NOTE: This method is a no-op for sockets other than TCP.
 	ModerateRecvBuf(copied int)
+
+	// IPTables returns the iptables for this endpoint's stack.
+	IPTables() (iptables.IPTables, error)
 }
 
 // WriteOptions contains options for Endpoint.Write.
diff --git a/pkg/tcpip/transport/icmp/BUILD b/pkg/tcpip/transport/icmp/BUILD
index 62182a3e6..d78a162b8 100644
--- a/pkg/tcpip/transport/icmp/BUILD
+++ b/pkg/tcpip/transport/icmp/BUILD
@@ -31,6 +31,7 @@ go_library(
         "//pkg/tcpip",
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/stack",
         "//pkg/tcpip/transport/raw",
         "//pkg/tcpip/transport/tcp",
diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index ba6671c26..a4527c041 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -21,6 +21,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
@@ -130,6 +131,11 @@ func (e *endpoint) Close() {
 // ModerateRecvBuf implements tcpip.Endpoint.ModerateRecvBuf.
 func (e *endpoint) ModerateRecvBuf(copied int) {}
 
+// IPTables implements tcpip.Endpoint.IPTables.
+func (e *endpoint) IPTables() (iptables.IPTables, error) {
+	return e.stack.IPTables(), nil
+}
+
 // Read reads data from the endpoint. This method does not block if
 // there is no data pending.
 func (e *endpoint) Read(addr *tcpip.FullAddress) (buffer.View, tcpip.ControlMessages, *tcpip.Error) {
diff --git a/pkg/tcpip/transport/raw/BUILD b/pkg/tcpip/transport/raw/BUILD
index bc4b255b4..7241f6c19 100644
--- a/pkg/tcpip/transport/raw/BUILD
+++ b/pkg/tcpip/transport/raw/BUILD
@@ -32,6 +32,7 @@ go_library(
         "//pkg/tcpip",
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/stack",
         "//pkg/waiter",
     ],
diff --git a/pkg/tcpip/transport/raw/endpoint.go b/pkg/tcpip/transport/raw/endpoint.go
index b633cd9d8..b4be855c1 100644
--- a/pkg/tcpip/transport/raw/endpoint.go
+++ b/pkg/tcpip/transport/raw/endpoint.go
@@ -32,6 +32,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
@@ -168,6 +169,11 @@ func (ep *endpoint) Close() {
 // ModerateRecvBuf implements tcpip.Endpoint.ModerateRecvBuf.
 func (ep *endpoint) ModerateRecvBuf(copied int) {}
 
+// IPTables implements tcpip.Endpoint.IPTables.
+func (ep *endpoint) IPTables() (iptables.IPTables, error) {
+	return ep.stack.IPTables(), nil
+}
+
 // Read implements tcpip.Endpoint.Read.
 func (ep *endpoint) Read(addr *tcpip.FullAddress) (buffer.View, tcpip.ControlMessages, *tcpip.Error) {
 	if !ep.associated {
@@ -484,7 +490,7 @@ func (ep *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask {
 
 // SetSockOpt implements tcpip.Endpoint.SetSockOpt.
 func (ep *endpoint) SetSockOpt(opt interface{}) *tcpip.Error {
-	return nil
+	return tcpip.ErrUnknownProtocolOption
 }
 
 // GetSockOptInt implements tcpip.Endpoint.GetSockOptInt.
diff --git a/pkg/tcpip/transport/tcp/BUILD b/pkg/tcpip/transport/tcp/BUILD
index 4cd25e8e2..1ee1a53f8 100644
--- a/pkg/tcpip/transport/tcp/BUILD
+++ b/pkg/tcpip/transport/tcp/BUILD
@@ -48,6 +48,7 @@ go_library(
         "//pkg/tcpip",
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/seqnum",
         "//pkg/tcpip/stack",
         "//pkg/tcpip/transport/raw",
diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go
index cc49c8272..353e2efaf 100644
--- a/pkg/tcpip/transport/tcp/endpoint.go
+++ b/pkg/tcpip/transport/tcp/endpoint.go
@@ -27,6 +27,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/seqnum"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/tmutex"
@@ -683,6 +684,11 @@ func (e *endpoint) ModerateRecvBuf(copied int) {
 	e.rcvListMu.Unlock()
 }
 
+// IPTables implements tcpip.Endpoint.IPTables.
+func (e *endpoint) IPTables() (iptables.IPTables, error) {
+	return e.stack.IPTables(), nil
+}
+
 // Read reads data from the endpoint.
 func (e *endpoint) Read(*tcpip.FullAddress) (buffer.View, tcpip.ControlMessages, *tcpip.Error) {
 	e.mu.RLock()
diff --git a/pkg/tcpip/transport/udp/BUILD b/pkg/tcpip/transport/udp/BUILD
index 6dac66b50..ac2666f69 100644
--- a/pkg/tcpip/transport/udp/BUILD
+++ b/pkg/tcpip/transport/udp/BUILD
@@ -32,6 +32,7 @@ go_library(
         "//pkg/tcpip",
         "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
+        "//pkg/tcpip/iptables",
         "//pkg/tcpip/stack",
         "//pkg/tcpip/transport/raw",
         "//pkg/waiter",
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 52a5df691..7210b3a9f 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -21,6 +21,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
@@ -172,6 +173,11 @@ func (e *endpoint) Close() {
 // ModerateRecvBuf implements tcpip.Endpoint.ModerateRecvBuf.
 func (e *endpoint) ModerateRecvBuf(copied int) {}
 
+// IPTables implements tcpip.Endpoint.IPTables.
+func (e *endpoint) IPTables() (iptables.IPTables, error) {
+	return e.stack.IPTables(), nil
+}
+
 // Read reads data from the endpoint. This method does not block if
 // there is no data pending.
 func (e *endpoint) Read(addr *tcpip.FullAddress) (buffer.View, tcpip.ControlMessages, *tcpip.Error) {