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-rw-r--r--pkg/sentry/socket/hostinet/stack.go5
-rw-r--r--pkg/sentry/socket/netlink/BUILD14
-rw-r--r--pkg/sentry/socket/netlink/message.go129
-rw-r--r--pkg/sentry/socket/netlink/message_test.go312
-rw-r--r--pkg/sentry/socket/netlink/provider.go2
-rw-r--r--pkg/sentry/socket/netlink/route/BUILD2
-rw-r--r--pkg/sentry/socket/netlink/route/protocol.go238
-rw-r--r--pkg/sentry/socket/netlink/socket.go54
-rw-r--r--pkg/sentry/socket/netlink/uevent/protocol.go2
-rw-r--r--pkg/sentry/socket/netstack/stack.go55
10 files changed, 706 insertions, 107 deletions
diff --git a/pkg/sentry/socket/hostinet/stack.go b/pkg/sentry/socket/hostinet/stack.go
index 034eca676..a48082631 100644
--- a/pkg/sentry/socket/hostinet/stack.go
+++ b/pkg/sentry/socket/hostinet/stack.go
@@ -310,6 +310,11 @@ func (s *Stack) InterfaceAddrs() map[int32][]inet.InterfaceAddr {
return addrs
}
+// AddInterfaceAddr implements inet.Stack.AddInterfaceAddr.
+func (s *Stack) AddInterfaceAddr(idx int32, addr inet.InterfaceAddr) error {
+ return syserror.EACCES
+}
+
// SupportsIPv6 implements inet.Stack.SupportsIPv6.
func (s *Stack) SupportsIPv6() bool {
return s.supportsIPv6
diff --git a/pkg/sentry/socket/netlink/BUILD b/pkg/sentry/socket/netlink/BUILD
index f8b8e467d..1911cd9b8 100644
--- a/pkg/sentry/socket/netlink/BUILD
+++ b/pkg/sentry/socket/netlink/BUILD
@@ -1,4 +1,4 @@
-load("//tools:defs.bzl", "go_library")
+load("//tools:defs.bzl", "go_library", "go_test")
package(licenses = ["notice"])
@@ -33,3 +33,15 @@ go_library(
"//pkg/waiter",
],
)
+
+go_test(
+ name = "netlink_test",
+ size = "small",
+ srcs = [
+ "message_test.go",
+ ],
+ deps = [
+ ":netlink",
+ "//pkg/abi/linux",
+ ],
+)
diff --git a/pkg/sentry/socket/netlink/message.go b/pkg/sentry/socket/netlink/message.go
index b21e0ca4b..4ea252ccb 100644
--- a/pkg/sentry/socket/netlink/message.go
+++ b/pkg/sentry/socket/netlink/message.go
@@ -30,8 +30,16 @@ func alignUp(length int, align uint) int {
return (length + int(align) - 1) &^ (int(align) - 1)
}
+// alignPad returns the length of padding required for alignment.
+//
+// Preconditions: align is a power of two.
+func alignPad(length int, align uint) int {
+ return alignUp(length, align) - length
+}
+
// Message contains a complete serialized netlink message.
type Message struct {
+ hdr linux.NetlinkMessageHeader
buf []byte
}
@@ -40,10 +48,86 @@ type Message struct {
// The header length will be updated by Finalize.
func NewMessage(hdr linux.NetlinkMessageHeader) *Message {
return &Message{
+ hdr: hdr,
buf: binary.Marshal(nil, usermem.ByteOrder, hdr),
}
}
+// ParseMessage parses the first message seen at buf, returning the rest of the
+// buffer. If message is malformed, ok of false is returned. For last message,
+// padding check is loose, if there isn't enought padding, whole buf is consumed
+// and ok is set to true.
+func ParseMessage(buf []byte) (msg *Message, rest []byte, ok bool) {
+ b := BytesView(buf)
+
+ hdrBytes, ok := b.Extract(linux.NetlinkMessageHeaderSize)
+ if !ok {
+ return
+ }
+ var hdr linux.NetlinkMessageHeader
+ binary.Unmarshal(hdrBytes, usermem.ByteOrder, &hdr)
+
+ // Msg portion.
+ totalMsgLen := int(hdr.Length)
+ _, ok = b.Extract(totalMsgLen - linux.NetlinkMessageHeaderSize)
+ if !ok {
+ return
+ }
+
+ // Padding.
+ numPad := alignPad(totalMsgLen, linux.NLMSG_ALIGNTO)
+ // Linux permits the last message not being aligned, just consume all of it.
+ // Ref: net/netlink/af_netlink.c:netlink_rcv_skb
+ if numPad > len(b) {
+ numPad = len(b)
+ }
+ _, ok = b.Extract(numPad)
+ if !ok {
+ return
+ }
+
+ return &Message{
+ hdr: hdr,
+ buf: buf[:totalMsgLen],
+ }, []byte(b), true
+}
+
+// Header returns the header of this message.
+func (m *Message) Header() linux.NetlinkMessageHeader {
+ return m.hdr
+}
+
+// GetData unmarshals the payload message header from this netlink message, and
+// returns the attributes portion.
+func (m *Message) GetData(msg interface{}) (AttrsView, bool) {
+ b := BytesView(m.buf)
+
+ _, ok := b.Extract(linux.NetlinkMessageHeaderSize)
+ if !ok {
+ return nil, false
+ }
+
+ size := int(binary.Size(msg))
+ msgBytes, ok := b.Extract(size)
+ if !ok {
+ return nil, false
+ }
+ binary.Unmarshal(msgBytes, usermem.ByteOrder, msg)
+
+ numPad := alignPad(linux.NetlinkMessageHeaderSize+size, linux.NLMSG_ALIGNTO)
+ // Linux permits the last message not being aligned, just consume all of it.
+ // Ref: net/netlink/af_netlink.c:netlink_rcv_skb
+ if numPad > len(b) {
+ numPad = len(b)
+ }
+ _, ok = b.Extract(numPad)
+ if !ok {
+ return nil, false
+ }
+
+ return AttrsView(b), true
+}
+
// Finalize returns the []byte containing the entire message, with the total
// length set in the message header. The Message must not be modified after
// calling Finalize.
@@ -157,3 +241,48 @@ func (ms *MessageSet) AddMessage(hdr linux.NetlinkMessageHeader) *Message {
ms.Messages = append(ms.Messages, m)
return m
}
+
+// AttrsView is a view into the attributes portion of a netlink message.
+type AttrsView []byte
+
+// Empty returns whether there is no attribute left in v.
+func (v AttrsView) Empty() bool {
+ return len(v) == 0
+}
+
+// ParseFirst parses first netlink attribute at the beginning of v.
+func (v AttrsView) ParseFirst() (hdr linux.NetlinkAttrHeader, value []byte, rest AttrsView, ok bool) {
+ b := BytesView(v)
+
+ hdrBytes, ok := b.Extract(linux.NetlinkAttrHeaderSize)
+ if !ok {
+ return
+ }
+ binary.Unmarshal(hdrBytes, usermem.ByteOrder, &hdr)
+
+ value, ok = b.Extract(int(hdr.Length) - linux.NetlinkAttrHeaderSize)
+ if !ok {
+ return
+ }
+
+ _, ok = b.Extract(alignPad(int(hdr.Length), linux.NLA_ALIGNTO))
+ if !ok {
+ return
+ }
+
+ return hdr, value, AttrsView(b), ok
+}
+
+// BytesView supports extracting data from a byte slice with bounds checking.
+type BytesView []byte
+
+// Extract removes the first n bytes from v and returns it. If n is out of
+// bounds, it returns false.
+func (v *BytesView) Extract(n int) ([]byte, bool) {
+ if n < 0 || n > len(*v) {
+ return nil, false
+ }
+ extracted := (*v)[:n]
+ *v = (*v)[n:]
+ return extracted, true
+}
diff --git a/pkg/sentry/socket/netlink/message_test.go b/pkg/sentry/socket/netlink/message_test.go
new file mode 100644
index 000000000..ef13d9386
--- /dev/null
+++ b/pkg/sentry/socket/netlink/message_test.go
@@ -0,0 +1,312 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package message_test
+
+import (
+ "bytes"
+ "reflect"
+ "testing"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/sentry/socket/netlink"
+)
+
+type dummyNetlinkMsg struct {
+ Foo uint16
+}
+
+func TestParseMessage(t *testing.T) {
+ tests := []struct {
+ desc string
+ input []byte
+
+ header linux.NetlinkMessageHeader
+ dataMsg *dummyNetlinkMsg
+ restLen int
+ ok bool
+ }{
+ {
+ desc: "valid",
+ input: []byte{
+ 0x14, 0x00, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, 0x00, 0x00, // Data message with 2 bytes padding
+ },
+ header: linux.NetlinkMessageHeader{
+ Length: 20,
+ Type: 1,
+ Flags: 2,
+ Seq: 3,
+ PortID: 4,
+ },
+ dataMsg: &dummyNetlinkMsg{
+ Foo: 0x3130,
+ },
+ restLen: 0,
+ ok: true,
+ },
+ {
+ desc: "valid with next message",
+ input: []byte{
+ 0x14, 0x00, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, 0x00, 0x00, // Data message with 2 bytes padding
+ 0xFF, // Next message (rest)
+ },
+ header: linux.NetlinkMessageHeader{
+ Length: 20,
+ Type: 1,
+ Flags: 2,
+ Seq: 3,
+ PortID: 4,
+ },
+ dataMsg: &dummyNetlinkMsg{
+ Foo: 0x3130,
+ },
+ restLen: 1,
+ ok: true,
+ },
+ {
+ desc: "valid for last message without padding",
+ input: []byte{
+ 0x12, 0x00, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, // Data message
+ },
+ header: linux.NetlinkMessageHeader{
+ Length: 18,
+ Type: 1,
+ Flags: 2,
+ Seq: 3,
+ PortID: 4,
+ },
+ dataMsg: &dummyNetlinkMsg{
+ Foo: 0x3130,
+ },
+ restLen: 0,
+ ok: true,
+ },
+ {
+ desc: "valid for last message not to be aligned",
+ input: []byte{
+ 0x13, 0x00, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, // Data message
+ 0x00, // Excessive 1 byte permitted at end
+ },
+ header: linux.NetlinkMessageHeader{
+ Length: 19,
+ Type: 1,
+ Flags: 2,
+ Seq: 3,
+ PortID: 4,
+ },
+ dataMsg: &dummyNetlinkMsg{
+ Foo: 0x3130,
+ },
+ restLen: 0,
+ ok: true,
+ },
+ {
+ desc: "header.Length too short",
+ input: []byte{
+ 0x04, 0x00, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, 0x00, 0x00, // Data message with 2 bytes padding
+ },
+ ok: false,
+ },
+ {
+ desc: "header.Length too long",
+ input: []byte{
+ 0xFF, 0xFF, 0x00, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x02, 0x00, // Flags
+ 0x03, 0x00, 0x00, 0x00, // Seq
+ 0x04, 0x00, 0x00, 0x00, // PortID
+ 0x30, 0x31, 0x00, 0x00, // Data message with 2 bytes padding
+ },
+ ok: false,
+ },
+ {
+ desc: "header incomplete",
+ input: []byte{
+ 0x04, 0x00, 0x00, 0x00, // Length
+ },
+ ok: false,
+ },
+ {
+ desc: "empty message",
+ input: []byte{},
+ ok: false,
+ },
+ }
+ for _, test := range tests {
+ msg, rest, ok := netlink.ParseMessage(test.input)
+ if ok != test.ok {
+ t.Errorf("%v: got ok = %v, want = %v", test.desc, ok, test.ok)
+ continue
+ }
+ if !test.ok {
+ continue
+ }
+ if !reflect.DeepEqual(msg.Header(), test.header) {
+ t.Errorf("%v: got hdr = %+v, want = %+v", test.desc, msg.Header(), test.header)
+ }
+
+ dataMsg := &dummyNetlinkMsg{}
+ _, dataOk := msg.GetData(dataMsg)
+ if !dataOk {
+ t.Errorf("%v: GetData.ok = %v, want = true", test.desc, dataOk)
+ } else if !reflect.DeepEqual(dataMsg, test.dataMsg) {
+ t.Errorf("%v: GetData.msg = %+v, want = %+v", test.desc, dataMsg, test.dataMsg)
+ }
+
+ if got, want := rest, test.input[len(test.input)-test.restLen:]; !bytes.Equal(got, want) {
+ t.Errorf("%v: got rest = %v, want = %v", test.desc, got, want)
+ }
+ }
+}
+
+func TestAttrView(t *testing.T) {
+ tests := []struct {
+ desc string
+ input []byte
+
+ // Outputs for ParseFirst.
+ hdr linux.NetlinkAttrHeader
+ value []byte
+ restLen int
+ ok bool
+
+ // Outputs for Empty.
+ isEmpty bool
+ }{
+ {
+ desc: "valid",
+ input: []byte{
+ 0x06, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x30, 0x31, 0x00, 0x00, // Data with 2 bytes padding
+ },
+ hdr: linux.NetlinkAttrHeader{
+ Length: 6,
+ Type: 1,
+ },
+ value: []byte{0x30, 0x31},
+ restLen: 0,
+ ok: true,
+ isEmpty: false,
+ },
+ {
+ desc: "at alignment",
+ input: []byte{
+ 0x08, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x30, 0x31, 0x32, 0x33, // Data
+ },
+ hdr: linux.NetlinkAttrHeader{
+ Length: 8,
+ Type: 1,
+ },
+ value: []byte{0x30, 0x31, 0x32, 0x33},
+ restLen: 0,
+ ok: true,
+ isEmpty: false,
+ },
+ {
+ desc: "at alignment with rest data",
+ input: []byte{
+ 0x08, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x30, 0x31, 0x32, 0x33, // Data
+ 0xFF, 0xFE, // Rest data
+ },
+ hdr: linux.NetlinkAttrHeader{
+ Length: 8,
+ Type: 1,
+ },
+ value: []byte{0x30, 0x31, 0x32, 0x33},
+ restLen: 2,
+ ok: true,
+ isEmpty: false,
+ },
+ {
+ desc: "hdr.Length too long",
+ input: []byte{
+ 0xFF, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x30, 0x31, 0x32, 0x33, // Data
+ },
+ ok: false,
+ isEmpty: false,
+ },
+ {
+ desc: "hdr.Length too short",
+ input: []byte{
+ 0x01, 0x00, // Length
+ 0x01, 0x00, // Type
+ 0x30, 0x31, 0x32, 0x33, // Data
+ },
+ ok: false,
+ isEmpty: false,
+ },
+ {
+ desc: "empty",
+ input: []byte{},
+ ok: false,
+ isEmpty: true,
+ },
+ }
+ for _, test := range tests {
+ attrs := netlink.AttrsView(test.input)
+
+ // Test ParseFirst().
+ hdr, value, rest, ok := attrs.ParseFirst()
+ if ok != test.ok {
+ t.Errorf("%v: got ok = %v, want = %v", test.desc, ok, test.ok)
+ } else if test.ok {
+ if !reflect.DeepEqual(hdr, test.hdr) {
+ t.Errorf("%v: got hdr = %+v, want = %+v", test.desc, hdr, test.hdr)
+ }
+ if !bytes.Equal(value, test.value) {
+ t.Errorf("%v: got value = %v, want = %v", test.desc, value, test.value)
+ }
+ if wantRest := test.input[len(test.input)-test.restLen:]; !bytes.Equal(rest, wantRest) {
+ t.Errorf("%v: got rest = %v, want = %v", test.desc, rest, wantRest)
+ }
+ }
+
+ // Test Empty().
+ if got, want := attrs.Empty(), test.isEmpty; got != want {
+ t.Errorf("%v: got empty = %v, want = %v", test.desc, got, want)
+ }
+ }
+}
diff --git a/pkg/sentry/socket/netlink/provider.go b/pkg/sentry/socket/netlink/provider.go
index 07f860a49..b0dc70e5c 100644
--- a/pkg/sentry/socket/netlink/provider.go
+++ b/pkg/sentry/socket/netlink/provider.go
@@ -42,7 +42,7 @@ type Protocol interface {
// If err == nil, any messages added to ms will be sent back to the
// other end of the socket. Setting ms.Multi will cause an NLMSG_DONE
// message to be sent even if ms contains no messages.
- ProcessMessage(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *MessageSet) *syserr.Error
+ ProcessMessage(ctx context.Context, msg *Message, ms *MessageSet) *syserr.Error
}
// Provider is a function that creates a new Protocol for a specific netlink
diff --git a/pkg/sentry/socket/netlink/route/BUILD b/pkg/sentry/socket/netlink/route/BUILD
index 622a1eafc..93127398d 100644
--- a/pkg/sentry/socket/netlink/route/BUILD
+++ b/pkg/sentry/socket/netlink/route/BUILD
@@ -10,13 +10,11 @@ go_library(
visibility = ["//pkg/sentry:internal"],
deps = [
"//pkg/abi/linux",
- "//pkg/binary",
"//pkg/context",
"//pkg/sentry/inet",
"//pkg/sentry/kernel",
"//pkg/sentry/kernel/auth",
"//pkg/sentry/socket/netlink",
"//pkg/syserr",
- "//pkg/usermem",
],
)
diff --git a/pkg/sentry/socket/netlink/route/protocol.go b/pkg/sentry/socket/netlink/route/protocol.go
index 2b3c7f5b3..c84d8bd7c 100644
--- a/pkg/sentry/socket/netlink/route/protocol.go
+++ b/pkg/sentry/socket/netlink/route/protocol.go
@@ -17,16 +17,15 @@ package route
import (
"bytes"
+ "syscall"
"gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/binary"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/inet"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
"gvisor.dev/gvisor/pkg/sentry/socket/netlink"
"gvisor.dev/gvisor/pkg/syserr"
- "gvisor.dev/gvisor/pkg/usermem"
)
// commandKind describes the operational class of a message type.
@@ -69,13 +68,7 @@ func (p *Protocol) CanSend() bool {
}
// dumpLinks handles RTM_GETLINK dump requests.
-func (p *Protocol) dumpLinks(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error {
- // TODO(b/68878065): Only the dump variant of the types below are
- // supported.
- if hdr.Flags&linux.NLM_F_DUMP != linux.NLM_F_DUMP {
- return syserr.ErrNotSupported
- }
-
+func (p *Protocol) dumpLinks(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
// NLM_F_DUMP + RTM_GETLINK messages are supposed to include an
// ifinfomsg. However, Linux <3.9 only checked for rtgenmsg, and some
// userspace applications (including glibc) still include rtgenmsg.
@@ -99,44 +92,105 @@ func (p *Protocol) dumpLinks(ctx context.Context, hdr linux.NetlinkMessageHeader
return nil
}
- for id, i := range stack.Interfaces() {
- m := ms.AddMessage(linux.NetlinkMessageHeader{
- Type: linux.RTM_NEWLINK,
- })
+ for idx, i := range stack.Interfaces() {
+ addNewLinkMessage(ms, idx, i)
+ }
- m.Put(linux.InterfaceInfoMessage{
- Family: linux.AF_UNSPEC,
- Type: i.DeviceType,
- Index: id,
- Flags: i.Flags,
- })
+ return nil
+}
- m.PutAttrString(linux.IFLA_IFNAME, i.Name)
- m.PutAttr(linux.IFLA_MTU, i.MTU)
+// getLinks handles RTM_GETLINK requests.
+func (p *Protocol) getLink(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
+ stack := inet.StackFromContext(ctx)
+ if stack == nil {
+ // No network devices.
+ return nil
+ }
- mac := make([]byte, 6)
- brd := mac
- if len(i.Addr) > 0 {
- mac = i.Addr
- brd = bytes.Repeat([]byte{0xff}, len(i.Addr))
+ // Parse message.
+ var ifi linux.InterfaceInfoMessage
+ attrs, ok := msg.GetData(&ifi)
+ if !ok {
+ return syserr.ErrInvalidArgument
+ }
+
+ // Parse attributes.
+ var byName []byte
+ for !attrs.Empty() {
+ ahdr, value, rest, ok := attrs.ParseFirst()
+ if !ok {
+ return syserr.ErrInvalidArgument
}
- m.PutAttr(linux.IFLA_ADDRESS, mac)
- m.PutAttr(linux.IFLA_BROADCAST, brd)
+ attrs = rest
- // TODO(gvisor.dev/issue/578): There are many more attributes.
+ switch ahdr.Type {
+ case linux.IFLA_IFNAME:
+ if len(value) < 1 {
+ return syserr.ErrInvalidArgument
+ }
+ byName = value[:len(value)-1]
+
+ // TODO(gvisor.dev/issue/578): Support IFLA_EXT_MASK.
+ }
}
+ found := false
+ for idx, i := range stack.Interfaces() {
+ switch {
+ case ifi.Index > 0:
+ if idx != ifi.Index {
+ continue
+ }
+ case byName != nil:
+ if string(byName) != i.Name {
+ continue
+ }
+ default:
+ // Criteria not specified.
+ return syserr.ErrInvalidArgument
+ }
+
+ addNewLinkMessage(ms, idx, i)
+ found = true
+ break
+ }
+ if !found {
+ return syserr.ErrNoDevice
+ }
return nil
}
-// dumpAddrs handles RTM_GETADDR dump requests.
-func (p *Protocol) dumpAddrs(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error {
- // TODO(b/68878065): Only the dump variant of the types below are
- // supported.
- if hdr.Flags&linux.NLM_F_DUMP != linux.NLM_F_DUMP {
- return syserr.ErrNotSupported
+// addNewLinkMessage appends RTM_NEWLINK message for the given interface into
+// the message set.
+func addNewLinkMessage(ms *netlink.MessageSet, idx int32, i inet.Interface) {
+ m := ms.AddMessage(linux.NetlinkMessageHeader{
+ Type: linux.RTM_NEWLINK,
+ })
+
+ m.Put(linux.InterfaceInfoMessage{
+ Family: linux.AF_UNSPEC,
+ Type: i.DeviceType,
+ Index: idx,
+ Flags: i.Flags,
+ })
+
+ m.PutAttrString(linux.IFLA_IFNAME, i.Name)
+ m.PutAttr(linux.IFLA_MTU, i.MTU)
+
+ mac := make([]byte, 6)
+ brd := mac
+ if len(i.Addr) > 0 {
+ mac = i.Addr
+ brd = bytes.Repeat([]byte{0xff}, len(i.Addr))
}
+ m.PutAttr(linux.IFLA_ADDRESS, mac)
+ m.PutAttr(linux.IFLA_BROADCAST, brd)
+
+ // TODO(gvisor.dev/issue/578): There are many more attributes.
+}
+// dumpAddrs handles RTM_GETADDR dump requests.
+func (p *Protocol) dumpAddrs(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
// RTM_GETADDR dump requests need not contain anything more than the
// netlink header and 1 byte protocol family common to all
// NETLINK_ROUTE requests.
@@ -168,6 +222,7 @@ func (p *Protocol) dumpAddrs(ctx context.Context, hdr linux.NetlinkMessageHeader
Index: uint32(id),
})
+ m.PutAttr(linux.IFA_LOCAL, []byte(a.Addr))
m.PutAttr(linux.IFA_ADDRESS, []byte(a.Addr))
// TODO(gvisor.dev/issue/578): There are many more attributes.
@@ -252,12 +307,12 @@ func fillRoute(routes []inet.Route, addr []byte) (inet.Route, *syserr.Error) {
}
// parseForDestination parses a message as format of RouteMessage-RtAttr-dst.
-func parseForDestination(data []byte) ([]byte, *syserr.Error) {
+func parseForDestination(msg *netlink.Message) ([]byte, *syserr.Error) {
var rtMsg linux.RouteMessage
- if len(data) < linux.SizeOfRouteMessage {
+ attrs, ok := msg.GetData(&rtMsg)
+ if !ok {
return nil, syserr.ErrInvalidArgument
}
- binary.Unmarshal(data[:linux.SizeOfRouteMessage], usermem.ByteOrder, &rtMsg)
// iproute2 added the RTM_F_LOOKUP_TABLE flag in version v4.4.0. See
// commit bc234301af12. Note we don't check this flag for backward
// compatibility.
@@ -265,26 +320,15 @@ func parseForDestination(data []byte) ([]byte, *syserr.Error) {
return nil, syserr.ErrNotSupported
}
- data = data[linux.SizeOfRouteMessage:]
-
- // TODO(gvisor.dev/issue/1611): Add generic attribute parsing.
- var rtAttr linux.RtAttr
- if len(data) < linux.SizeOfRtAttr {
- return nil, syserr.ErrInvalidArgument
+ // Expect first attribute is RTA_DST.
+ if hdr, value, _, ok := attrs.ParseFirst(); ok && hdr.Type == linux.RTA_DST {
+ return value, nil
}
- binary.Unmarshal(data[:linux.SizeOfRtAttr], usermem.ByteOrder, &rtAttr)
- if rtAttr.Type != linux.RTA_DST {
- return nil, syserr.ErrInvalidArgument
- }
-
- if len(data) < int(rtAttr.Len) {
- return nil, syserr.ErrInvalidArgument
- }
- return data[linux.SizeOfRtAttr:rtAttr.Len], nil
+ return nil, syserr.ErrInvalidArgument
}
// dumpRoutes handles RTM_GETROUTE requests.
-func (p *Protocol) dumpRoutes(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error {
+func (p *Protocol) dumpRoutes(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
// RTM_GETROUTE dump requests need not contain anything more than the
// netlink header and 1 byte protocol family common to all
// NETLINK_ROUTE requests.
@@ -295,10 +339,11 @@ func (p *Protocol) dumpRoutes(ctx context.Context, hdr linux.NetlinkMessageHeade
return nil
}
+ hdr := msg.Header()
routeTables := stack.RouteTable()
if hdr.Flags == linux.NLM_F_REQUEST {
- dst, err := parseForDestination(data)
+ dst, err := parseForDestination(msg)
if err != nil {
return err
}
@@ -357,10 +402,55 @@ func (p *Protocol) dumpRoutes(ctx context.Context, hdr linux.NetlinkMessageHeade
return nil
}
+// newAddr handles RTM_NEWADDR requests.
+func (p *Protocol) newAddr(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
+ stack := inet.StackFromContext(ctx)
+ if stack == nil {
+ // No network stack.
+ return syserr.ErrProtocolNotSupported
+ }
+
+ var ifa linux.InterfaceAddrMessage
+ attrs, ok := msg.GetData(&ifa)
+ if !ok {
+ return syserr.ErrInvalidArgument
+ }
+
+ for !attrs.Empty() {
+ ahdr, value, rest, ok := attrs.ParseFirst()
+ if !ok {
+ return syserr.ErrInvalidArgument
+ }
+ attrs = rest
+
+ switch ahdr.Type {
+ case linux.IFA_LOCAL:
+ err := stack.AddInterfaceAddr(int32(ifa.Index), inet.InterfaceAddr{
+ Family: ifa.Family,
+ PrefixLen: ifa.PrefixLen,
+ Flags: ifa.Flags,
+ Addr: value,
+ })
+ if err == syscall.EEXIST {
+ flags := msg.Header().Flags
+ if flags&linux.NLM_F_EXCL != 0 {
+ return syserr.ErrExists
+ }
+ } else if err != nil {
+ return syserr.ErrInvalidArgument
+ }
+ }
+ }
+ return nil
+}
+
// ProcessMessage implements netlink.Protocol.ProcessMessage.
-func (p *Protocol) ProcessMessage(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error {
+func (p *Protocol) ProcessMessage(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
+ hdr := msg.Header()
+
// All messages start with a 1 byte protocol family.
- if len(data) < 1 {
+ var family uint8
+ if _, ok := msg.GetData(&family); !ok {
// Linux ignores messages missing the protocol family. See
// net/core/rtnetlink.c:rtnetlink_rcv_msg.
return nil
@@ -374,16 +464,32 @@ func (p *Protocol) ProcessMessage(ctx context.Context, hdr linux.NetlinkMessageH
}
}
- switch hdr.Type {
- case linux.RTM_GETLINK:
- return p.dumpLinks(ctx, hdr, data, ms)
- case linux.RTM_GETADDR:
- return p.dumpAddrs(ctx, hdr, data, ms)
- case linux.RTM_GETROUTE:
- return p.dumpRoutes(ctx, hdr, data, ms)
- default:
- return syserr.ErrNotSupported
+ if hdr.Flags&linux.NLM_F_DUMP == linux.NLM_F_DUMP {
+ // TODO(b/68878065): Only the dump variant of the types below are
+ // supported.
+ switch hdr.Type {
+ case linux.RTM_GETLINK:
+ return p.dumpLinks(ctx, msg, ms)
+ case linux.RTM_GETADDR:
+ return p.dumpAddrs(ctx, msg, ms)
+ case linux.RTM_GETROUTE:
+ return p.dumpRoutes(ctx, msg, ms)
+ default:
+ return syserr.ErrNotSupported
+ }
+ } else if hdr.Flags&linux.NLM_F_REQUEST == linux.NLM_F_REQUEST {
+ switch hdr.Type {
+ case linux.RTM_GETLINK:
+ return p.getLink(ctx, msg, ms)
+ case linux.RTM_GETROUTE:
+ return p.dumpRoutes(ctx, msg, ms)
+ case linux.RTM_NEWADDR:
+ return p.newAddr(ctx, msg, ms)
+ default:
+ return syserr.ErrNotSupported
+ }
}
+ return syserr.ErrNotSupported
}
// init registers the NETLINK_ROUTE provider.
diff --git a/pkg/sentry/socket/netlink/socket.go b/pkg/sentry/socket/netlink/socket.go
index c4b95debb..2ca02567d 100644
--- a/pkg/sentry/socket/netlink/socket.go
+++ b/pkg/sentry/socket/netlink/socket.go
@@ -644,47 +644,38 @@ func (s *Socket) sendResponse(ctx context.Context, ms *MessageSet) *syserr.Error
return nil
}
-func (s *Socket) dumpErrorMesage(ctx context.Context, hdr linux.NetlinkMessageHeader, ms *MessageSet, err *syserr.Error) *syserr.Error {
+func dumpErrorMesage(hdr linux.NetlinkMessageHeader, ms *MessageSet, err *syserr.Error) {
m := ms.AddMessage(linux.NetlinkMessageHeader{
Type: linux.NLMSG_ERROR,
})
-
m.Put(linux.NetlinkErrorMessage{
Error: int32(-err.ToLinux().Number()),
Header: hdr,
})
- return nil
+}
+func dumpAckMesage(hdr linux.NetlinkMessageHeader, ms *MessageSet) {
+ m := ms.AddMessage(linux.NetlinkMessageHeader{
+ Type: linux.NLMSG_ERROR,
+ })
+ m.Put(linux.NetlinkErrorMessage{
+ Error: 0,
+ Header: hdr,
+ })
}
// processMessages handles each message in buf, passing it to the protocol
// handler for final handling.
func (s *Socket) processMessages(ctx context.Context, buf []byte) *syserr.Error {
for len(buf) > 0 {
- if len(buf) < linux.NetlinkMessageHeaderSize {
+ msg, rest, ok := ParseMessage(buf)
+ if !ok {
// Linux ignores messages that are too short. See
// net/netlink/af_netlink.c:netlink_rcv_skb.
break
}
-
- var hdr linux.NetlinkMessageHeader
- binary.Unmarshal(buf[:linux.NetlinkMessageHeaderSize], usermem.ByteOrder, &hdr)
-
- if hdr.Length < linux.NetlinkMessageHeaderSize || uint64(hdr.Length) > uint64(len(buf)) {
- // Linux ignores malformed messages. See
- // net/netlink/af_netlink.c:netlink_rcv_skb.
- break
- }
-
- // Data from this message.
- data := buf[linux.NetlinkMessageHeaderSize:hdr.Length]
-
- // Advance to the next message.
- next := alignUp(int(hdr.Length), linux.NLMSG_ALIGNTO)
- if next >= len(buf)-1 {
- next = len(buf) - 1
- }
- buf = buf[next:]
+ buf = rest
+ hdr := msg.Header()
// Ignore control messages.
if hdr.Type < linux.NLMSG_MIN_TYPE {
@@ -692,19 +683,10 @@ func (s *Socket) processMessages(ctx context.Context, buf []byte) *syserr.Error
}
ms := NewMessageSet(s.portID, hdr.Seq)
- var err *syserr.Error
- // TODO(b/68877377): ACKs not supported yet.
- if hdr.Flags&linux.NLM_F_ACK == linux.NLM_F_ACK {
- err = syserr.ErrNotSupported
- } else {
-
- err = s.protocol.ProcessMessage(ctx, hdr, data, ms)
- }
- if err != nil {
- ms = NewMessageSet(s.portID, hdr.Seq)
- if err := s.dumpErrorMesage(ctx, hdr, ms, err); err != nil {
- return err
- }
+ if err := s.protocol.ProcessMessage(ctx, msg, ms); err != nil {
+ dumpErrorMesage(hdr, ms, err)
+ } else if hdr.Flags&linux.NLM_F_ACK == linux.NLM_F_ACK {
+ dumpAckMesage(hdr, ms)
}
if err := s.sendResponse(ctx, ms); err != nil {
diff --git a/pkg/sentry/socket/netlink/uevent/protocol.go b/pkg/sentry/socket/netlink/uevent/protocol.go
index 1ee4296bc..029ba21b5 100644
--- a/pkg/sentry/socket/netlink/uevent/protocol.go
+++ b/pkg/sentry/socket/netlink/uevent/protocol.go
@@ -49,7 +49,7 @@ func (p *Protocol) CanSend() bool {
}
// ProcessMessage implements netlink.Protocol.ProcessMessage.
-func (p *Protocol) ProcessMessage(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error {
+func (p *Protocol) ProcessMessage(ctx context.Context, msg *netlink.Message, ms *netlink.MessageSet) *syserr.Error {
// Silently ignore all messages.
return nil
}
diff --git a/pkg/sentry/socket/netstack/stack.go b/pkg/sentry/socket/netstack/stack.go
index 31ea66eca..0692482e9 100644
--- a/pkg/sentry/socket/netstack/stack.go
+++ b/pkg/sentry/socket/netstack/stack.go
@@ -20,6 +20,8 @@ import (
"gvisor.dev/gvisor/pkg/sentry/inet"
"gvisor.dev/gvisor/pkg/sentry/socket/netfilter"
"gvisor.dev/gvisor/pkg/syserr"
+ "gvisor.dev/gvisor/pkg/syserror"
+ "gvisor.dev/gvisor/pkg/tcpip"
"gvisor.dev/gvisor/pkg/tcpip/header"
"gvisor.dev/gvisor/pkg/tcpip/iptables"
"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
@@ -88,6 +90,59 @@ func (s *Stack) InterfaceAddrs() map[int32][]inet.InterfaceAddr {
return nicAddrs
}
+// AddInterfaceAddr implements inet.Stack.AddInterfaceAddr.
+func (s *Stack) AddInterfaceAddr(idx int32, addr inet.InterfaceAddr) error {
+ var (
+ protocol tcpip.NetworkProtocolNumber
+ address tcpip.Address
+ )
+ switch addr.Family {
+ case linux.AF_INET:
+ if len(addr.Addr) < header.IPv4AddressSize {
+ return syserror.EINVAL
+ }
+ if addr.PrefixLen > header.IPv4AddressSize*8 {
+ return syserror.EINVAL
+ }
+ protocol = ipv4.ProtocolNumber
+ address = tcpip.Address(addr.Addr[:header.IPv4AddressSize])
+
+ case linux.AF_INET6:
+ if len(addr.Addr) < header.IPv6AddressSize {
+ return syserror.EINVAL
+ }
+ if addr.PrefixLen > header.IPv6AddressSize*8 {
+ return syserror.EINVAL
+ }
+ protocol = ipv6.ProtocolNumber
+ address = tcpip.Address(addr.Addr[:header.IPv6AddressSize])
+
+ default:
+ return syserror.ENOTSUP
+ }
+
+ protocolAddress := tcpip.ProtocolAddress{
+ Protocol: protocol,
+ AddressWithPrefix: tcpip.AddressWithPrefix{
+ Address: address,
+ PrefixLen: int(addr.PrefixLen),
+ },
+ }
+
+ // Attach address to interface.
+ if err := s.Stack.AddProtocolAddressWithOptions(tcpip.NICID(idx), protocolAddress, stack.CanBePrimaryEndpoint); err != nil {
+ return syserr.TranslateNetstackError(err).ToError()
+ }
+
+ // Add route for local network.
+ s.Stack.AddRoute(tcpip.Route{
+ Destination: protocolAddress.AddressWithPrefix.Subnet(),
+ Gateway: "", // No gateway for local network.
+ NIC: tcpip.NICID(idx),
+ })
+ return nil
+}
+
// TCPReceiveBufferSize implements inet.Stack.TCPReceiveBufferSize.
func (s *Stack) TCPReceiveBufferSize() (inet.TCPBufferSize, error) {
var rs tcp.ReceiveBufferSizeOption