diff --git a/pkg/abi/linux/socket.go b/pkg/abi/linux/socket.go index 95871b8a5..f60e42997 100644 --- a/pkg/abi/linux/socket.go +++ b/pkg/abi/linux/socket.go @@ -542,6 +542,15 @@ type ControlMessageIPPacketInfo struct { DestinationAddr InetAddr } +// ControlMessageIPv6PacketInfo represents struct in6_pktinfo from linux/ipv6.h. +// +// +marshal +// +stateify savable +type ControlMessageIPv6PacketInfo struct { + Addr Inet6Addr + NIC uint32 +} + // SizeOfControlMessageCredentials is the binary size of a // ControlMessageCredentials struct. var SizeOfControlMessageCredentials = (*ControlMessageCredentials)(nil).SizeBytes() @@ -566,6 +575,10 @@ const SizeOfControlMessageTClass = 4 // control message. const SizeOfControlMessageIPPacketInfo = 12 +// SizeOfControlMessageIPv6PacketInfo is the size of a +// ControlMessageIPv6PacketInfo. +const SizeOfControlMessageIPv6PacketInfo = 20 + // SCM_MAX_FD is the maximum number of FDs accepted in a single sendmsg call. // From net/scm.h. const SCM_MAX_FD = 253 diff --git a/pkg/sentry/socket/control/control.go b/pkg/sentry/socket/control/control.go index 00a5e729a..f9a5b0df1 100644 --- a/pkg/sentry/socket/control/control.go +++ b/pkg/sentry/socket/control/control.go @@ -355,6 +355,17 @@ func PackIPPacketInfo(t *kernel.Task, packetInfo *linux.ControlMessageIPPacketIn ) } +// PackIPv6PacketInfo packs an IPV6_PKTINFO socket control message. +func PackIPv6PacketInfo(t *kernel.Task, packetInfo *linux.ControlMessageIPv6PacketInfo, buf []byte) []byte { + return putCmsgStruct( + buf, + linux.SOL_IPV6, + linux.IPV6_PKTINFO, + t.Arch().Width(), + packetInfo, + ) +} + // PackOriginalDstAddress packs an IP_RECVORIGINALDSTADDR socket control message. func PackOriginalDstAddress(t *kernel.Task, originalDstAddress linux.SockAddr, buf []byte) []byte { var level uint32 @@ -412,6 +423,10 @@ func PackControlMessages(t *kernel.Task, cmsgs socket.ControlMessages, buf []byt buf = PackIPPacketInfo(t, &cmsgs.IP.PacketInfo, buf) } + if cmsgs.IP.HasIPv6PacketInfo { + buf = PackIPv6PacketInfo(t, &cmsgs.IP.IPv6PacketInfo, buf) + } + if cmsgs.IP.OriginalDstAddress != nil { buf = PackOriginalDstAddress(t, cmsgs.IP.OriginalDstAddress, buf) } @@ -453,6 +468,10 @@ func CmsgsSpace(t *kernel.Task, cmsgs socket.ControlMessages) int { space += cmsgSpace(t, linux.SizeOfControlMessageIPPacketInfo) } + if cmsgs.IP.HasIPv6PacketInfo { + space += cmsgSpace(t, linux.SizeOfControlMessageIPv6PacketInfo) + } + if cmsgs.IP.OriginalDstAddress != nil { space += cmsgSpace(t, cmsgs.IP.OriginalDstAddress.SizeBytes()) } diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index aa081e90d..dedc32dda 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -1371,6 +1371,14 @@ func getSockOptIPv6(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name v := primitive.Int32(boolToInt32(ep.SocketOptions().GetReceiveOriginalDstAddress())) return &v, nil + case linux.IPV6_RECVPKTINFO: + if outLen < sizeOfInt32 { + return nil, syserr.ErrInvalidArgument + } + + v := primitive.Int32(boolToInt32(ep.SocketOptions().GetIPv6ReceivePacketInfo())) + return &v, nil + case linux.IP6T_ORIGINAL_DST: if outLen < sockAddrInet6Size { return nil, syserr.ErrInvalidArgument @@ -2127,6 +2135,15 @@ func setSockOptIPv6(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name ep.SocketOptions().SetReceiveOriginalDstAddress(v != 0) return nil + case linux.IPV6_RECVPKTINFO: + if len(optVal) < sizeOfInt32 { + return syserr.ErrInvalidArgument + } + v := int32(hostarch.ByteOrder.Uint32(optVal)) + + ep.SocketOptions().SetIPv6ReceivePacketInfo(v != 0) + return nil + case linux.IPV6_TCLASS: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument @@ -2516,7 +2533,6 @@ func emitUnimplementedEventIPv6(t *kernel.Task, name int) { linux.IPV6_RECVHOPLIMIT, linux.IPV6_RECVHOPOPTS, linux.IPV6_RECVPATHMTU, - linux.IPV6_RECVPKTINFO, linux.IPV6_RECVRTHDR, linux.IPV6_RTHDR, linux.IPV6_RTHDRDSTOPTS, @@ -2742,6 +2758,8 @@ func (s *socketOpsCommon) controlMessages(cm tcpip.ControlMessages) socket.Contr TClass: readCM.TClass, HasIPPacketInfo: readCM.HasIPPacketInfo, PacketInfo: readCM.PacketInfo, + HasIPv6PacketInfo: readCM.HasIPv6PacketInfo, + IPv6PacketInfo: readCM.IPv6PacketInfo, OriginalDstAddress: readCM.OriginalDstAddress, SockErr: readCM.SockErr, }, diff --git a/pkg/sentry/socket/socket.go b/pkg/sentry/socket/socket.go index 841d5bd55..2f0eb4a6c 100644 --- a/pkg/sentry/socket/socket.go +++ b/pkg/sentry/socket/socket.go @@ -56,6 +56,17 @@ func packetInfoToLinux(packetInfo tcpip.IPPacketInfo) linux.ControlMessageIPPack return p } +// ipv6PacketInfoToLinux converts IPv6PacketInfo from tcpip format to Linux +// format. +func ipv6PacketInfoToLinux(packetInfo tcpip.IPv6PacketInfo) linux.ControlMessageIPv6PacketInfo { + var p linux.ControlMessageIPv6PacketInfo + if n := copy(p.Addr[:], []byte(packetInfo.Addr)); n != len(p.Addr) { + panic(fmt.Sprintf("got copy(%x, %x) = %d, want = %d", p.Addr, packetInfo.Addr, n, len(p.Addr))) + } + p.NIC = uint32(packetInfo.NIC) + return p +} + // errOriginToLinux maps tcpip socket origin to Linux socket origin constants. func errOriginToLinux(origin tcpip.SockErrOrigin) uint8 { switch origin { @@ -114,7 +125,7 @@ func NewIPControlMessages(family int, cmgs tcpip.ControlMessages) IPControlMessa if cmgs.HasOriginalDstAddress { orgDstAddr, _ = ConvertAddress(family, cmgs.OriginalDstAddress) } - return IPControlMessages{ + cm := IPControlMessages{ HasTimestamp: cmgs.HasTimestamp, Timestamp: cmgs.Timestamp, HasInq: cmgs.HasInq, @@ -125,9 +136,16 @@ func NewIPControlMessages(family int, cmgs tcpip.ControlMessages) IPControlMessa TClass: cmgs.TClass, HasIPPacketInfo: cmgs.HasIPPacketInfo, PacketInfo: packetInfoToLinux(cmgs.PacketInfo), + HasIPv6PacketInfo: cmgs.HasIPv6PacketInfo, OriginalDstAddress: orgDstAddr, SockErr: sockErrCmsgToLinux(cmgs.SockErr), } + + if cm.HasIPv6PacketInfo { + cm.IPv6PacketInfo = ipv6PacketInfoToLinux(cmgs.IPv6PacketInfo) + } + + return cm } // IPControlMessages contains socket control messages for IP sockets. @@ -166,6 +184,12 @@ type IPControlMessages struct { // PacketInfo holds interface and address data on an incoming packet. PacketInfo linux.ControlMessageIPPacketInfo + // HasIPv6PacketInfo indicates whether IPv6PacketInfo is set. + HasIPv6PacketInfo bool + + // PacketInfo holds interface and address data on an incoming packet. + IPv6PacketInfo linux.ControlMessageIPv6PacketInfo + // OriginalDestinationAddress holds the original destination address // and port of the incoming packet. OriginalDstAddress linux.SockAddr diff --git a/pkg/tcpip/checker/checker.go b/pkg/tcpip/checker/checker.go index 2f34bf8dd..24c2c3e6b 100644 --- a/pkg/tcpip/checker/checker.go +++ b/pkg/tcpip/checker/checker.go @@ -324,6 +324,19 @@ func ReceiveIPPacketInfo(want tcpip.IPPacketInfo) ControlMessagesChecker { } } +// ReceiveIPv6PacketInfo creates a checker that checks the IPv6PacketInfo field +// in ControlMessages. +func ReceiveIPv6PacketInfo(want tcpip.IPv6PacketInfo) ControlMessagesChecker { + return func(t *testing.T, cm tcpip.ControlMessages) { + t.Helper() + if !cm.HasIPv6PacketInfo { + t.Errorf("got cm.HasIPv6PacketInfo = %t, want = true", cm.HasIPv6PacketInfo) + } else if diff := cmp.Diff(want, cm.IPv6PacketInfo); diff != "" { + t.Errorf("IPv6PacketInfo mismatch (-want +got):\n%s", diff) + } + } +} + // ReceiveOriginalDstAddr creates a checker that checks the OriginalDstAddress // field in ControlMessages. func ReceiveOriginalDstAddr(want tcpip.FullAddress) ControlMessagesChecker { diff --git a/pkg/tcpip/socketops.go b/pkg/tcpip/socketops.go index 34ac62444..b0b2d0afd 100644 --- a/pkg/tcpip/socketops.go +++ b/pkg/tcpip/socketops.go @@ -170,10 +170,14 @@ type SocketOptions struct { // message is passed with incoming packets. receiveTClassEnabled uint32 - // receivePacketInfoEnabled is used to specify if more inforamtion is - // provided with incoming packets such as interface index and address. + // receivePacketInfoEnabled is used to specify if more information is + // provided with incoming IPv4 packets. receivePacketInfoEnabled uint32 + // receivePacketInfoEnabled is used to specify if more information is + // provided with incoming IPv6 packets. + receiveIPv6PacketInfoEnabled uint32 + // hdrIncludeEnabled is used to indicate for a raw endpoint that all packets // being written have an IP header and the endpoint should not attach an IP // header. @@ -360,6 +364,16 @@ func (so *SocketOptions) SetReceivePacketInfo(v bool) { storeAtomicBool(&so.receivePacketInfoEnabled, v) } +// GetIPv6ReceivePacketInfo gets value for IPV6_RECVPKTINFO option. +func (so *SocketOptions) GetIPv6ReceivePacketInfo() bool { + return atomic.LoadUint32(&so.receiveIPv6PacketInfoEnabled) != 0 +} + +// SetIPv6ReceivePacketInfo sets value for IPV6_RECVPKTINFO option. +func (so *SocketOptions) SetIPv6ReceivePacketInfo(v bool) { + storeAtomicBool(&so.receiveIPv6PacketInfoEnabled, v) +} + // GetHeaderIncluded gets value for IP_HDRINCL option. func (so *SocketOptions) GetHeaderIncluded() bool { return atomic.LoadUint32(&so.hdrIncludedEnabled) != 0 diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index a9ce148b9..c5e896295 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -451,6 +451,12 @@ type ControlMessages struct { // PacketInfo holds interface and address data on an incoming packet. PacketInfo IPPacketInfo + // HasIPv6PacketInfo indicates whether IPv6PacketInfo is set. + HasIPv6PacketInfo bool + + // IPv6PacketInfo holds interface and address data on an incoming packet. + IPv6PacketInfo IPv6PacketInfo + // HasOriginalDestinationAddress indicates whether OriginalDstAddress is // set. HasOriginalDstAddress bool @@ -1164,6 +1170,14 @@ type IPPacketInfo struct { DestinationAddr Address } +// IPv6PacketInfo is the message structure for IPV6_PKTINFO. +// +// +stateify savable +type IPv6PacketInfo struct { + Addr Address + NIC NICID +} + // SendBufferSizeOption is used by stack.(Stack*).Option/SetOption to // get/set the default, min and max send buffer sizes. type SendBufferSizeOption struct { diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index 4255457f9..b355fa7eb 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -243,19 +243,29 @@ func (e *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResult cm.HasTOS = true cm.TOS = p.tos } + + if e.ops.GetReceivePacketInfo() { + cm.HasIPPacketInfo = true + cm.PacketInfo = p.packetInfo + } case header.IPv6ProtocolNumber: if e.ops.GetReceiveTClass() { cm.HasTClass = true // Although TClass is an 8-bit value it's read in the CMsg as a uint32. cm.TClass = uint32(p.tos) } + + if e.ops.GetIPv6ReceivePacketInfo() { + cm.HasIPv6PacketInfo = true + cm.IPv6PacketInfo = tcpip.IPv6PacketInfo{ + NIC: p.packetInfo.NIC, + Addr: p.packetInfo.DestinationAddr, + } + } default: panic(fmt.Sprintf("unrecognized network protocol = %d", p.netProto)) } - if e.ops.GetReceivePacketInfo() { - cm.HasIPPacketInfo = true - cm.PacketInfo = p.packetInfo - } + if e.ops.GetReceiveOriginalDstAddress() { cm.HasOriginalDstAddress = true cm.OriginalDstAddress = p.destinationAddress diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go index 3719b0dc7..b3199489c 100644 --- a/pkg/tcpip/transport/udp/udp_test.go +++ b/pkg/tcpip/transport/udp/udp_test.go @@ -1369,64 +1369,70 @@ func TestReadIncrementsPacketsReceived(t *testing.T) { func TestReadIPPacketInfo(t *testing.T) { tests := []struct { - name string - proto tcpip.NetworkProtocolNumber - flow testFlow - expectedLocalAddr tcpip.Address - expectedDestAddr tcpip.Address + name string + proto tcpip.NetworkProtocolNumber + flow testFlow + checker func(tcpip.NICID) checker.ControlMessagesChecker }{ { - name: "IPv4 unicast", - proto: header.IPv4ProtocolNumber, - flow: unicastV4, - expectedLocalAddr: stackAddr, - expectedDestAddr: stackAddr, + name: "IPv4 unicast", + proto: header.IPv4ProtocolNumber, + flow: unicastV4, + checker: func(id tcpip.NICID) checker.ControlMessagesChecker { + return checker.ReceiveIPPacketInfo(tcpip.IPPacketInfo{ + NIC: id, + LocalAddr: stackAddr, + DestinationAddr: stackAddr, + }) + }, }, { name: "IPv4 multicast", proto: header.IPv4ProtocolNumber, flow: multicastV4, - // This should actually be a unicast address assigned to the interface. - // - // TODO(gvisor.dev/issue/3556): This check is validating incorrect - // behaviour. We still include the test so that once the bug is - // resolved, this test will start to fail and the individual tasked - // with fixing this bug knows to also fix this test :). - expectedLocalAddr: multicastAddr, - expectedDestAddr: multicastAddr, + checker: func(id tcpip.NICID) checker.ControlMessagesChecker { + return checker.ReceiveIPPacketInfo(tcpip.IPPacketInfo{ + NIC: id, + // TODO(gvisor.dev/issue/3556): Check for a unicast address. + LocalAddr: multicastAddr, + DestinationAddr: multicastAddr, + }) + }, }, { name: "IPv4 broadcast", proto: header.IPv4ProtocolNumber, flow: broadcast, - // This should actually be a unicast address assigned to the interface. - // - // TODO(gvisor.dev/issue/3556): This check is validating incorrect - // behaviour. We still include the test so that once the bug is - // resolved, this test will start to fail and the individual tasked - // with fixing this bug knows to also fix this test :). - expectedLocalAddr: broadcastAddr, - expectedDestAddr: broadcastAddr, + checker: func(id tcpip.NICID) checker.ControlMessagesChecker { + return checker.ReceiveIPPacketInfo(tcpip.IPPacketInfo{ + NIC: id, + // TODO(gvisor.dev/issue/3556): Check for a unicast address. + LocalAddr: broadcastAddr, + DestinationAddr: broadcastAddr, + }) + }, }, { - name: "IPv6 unicast", - proto: header.IPv6ProtocolNumber, - flow: unicastV6, - expectedLocalAddr: stackV6Addr, - expectedDestAddr: stackV6Addr, + name: "IPv6 unicast", + proto: header.IPv6ProtocolNumber, + flow: unicastV6, + checker: func(id tcpip.NICID) checker.ControlMessagesChecker { + return checker.ReceiveIPv6PacketInfo(tcpip.IPv6PacketInfo{ + NIC: id, + Addr: stackV6Addr, + }) + }, }, { name: "IPv6 multicast", proto: header.IPv6ProtocolNumber, flow: multicastV6, - // This should actually be a unicast address assigned to the interface. - // - // TODO(gvisor.dev/issue/3556): This check is validating incorrect - // behaviour. We still include the test so that once the bug is - // resolved, this test will start to fail and the individual tasked - // with fixing this bug knows to also fix this test :). - expectedLocalAddr: multicastV6Addr, - expectedDestAddr: multicastV6Addr, + checker: func(id tcpip.NICID) checker.ControlMessagesChecker { + return checker.ReceiveIPv6PacketInfo(tcpip.IPv6PacketInfo{ + NIC: id, + Addr: multicastV6Addr, + }) + }, }, } @@ -1449,13 +1455,16 @@ func TestReadIPPacketInfo(t *testing.T) { } } - c.ep.SocketOptions().SetReceivePacketInfo(true) + switch f := test.flow.netProto(); f { + case header.IPv4ProtocolNumber: + c.ep.SocketOptions().SetReceivePacketInfo(true) + case header.IPv6ProtocolNumber: + c.ep.SocketOptions().SetIPv6ReceivePacketInfo(true) + default: + t.Fatalf("unhandled protocol number = %d", f) + } - testRead(c, test.flow, checker.ReceiveIPPacketInfo(tcpip.IPPacketInfo{ - NIC: 1, - LocalAddr: test.expectedLocalAddr, - DestinationAddr: test.expectedDestAddr, - })) + testRead(c, test.flow, test.checker(c.nicID)) if got := c.s.Stats().UDP.PacketsReceived.Value(); got != 1 { t.Fatalf("Read did not increment PacketsReceived: got = %d, want = 1", got) diff --git a/test/syscalls/linux/socket_ipv6_udp_unbound.cc b/test/syscalls/linux/socket_ipv6_udp_unbound.cc index 612fd531c..c431bf771 100644 --- a/test/syscalls/linux/socket_ipv6_udp_unbound.cc +++ b/test/syscalls/linux/socket_ipv6_udp_unbound.cc @@ -39,6 +39,86 @@ namespace gvisor { namespace testing { +using ::testing::IsNull; +using ::testing::NotNull; + +TEST_P(IPv6UDPUnboundSocketTest, IPv6PacketInfo) { + auto sender_socket = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + auto receiver_socket = ASSERT_NO_ERRNO_AND_VALUE(NewSocket()); + + auto sender_addr = V6Loopback(); + ASSERT_THAT(bind(sender_socket->get(), AsSockAddr(&sender_addr.addr), + sender_addr.addr_len), + SyscallSucceeds()); + + auto receiver_addr = V6Loopback(); + ASSERT_THAT(bind(receiver_socket->get(), AsSockAddr(&receiver_addr.addr), + receiver_addr.addr_len), + SyscallSucceeds()); + socklen_t receiver_addr_len = receiver_addr.addr_len; + ASSERT_THAT(getsockname(receiver_socket->get(), + AsSockAddr(&receiver_addr.addr), &receiver_addr_len), + SyscallSucceeds()); + ASSERT_EQ(receiver_addr_len, receiver_addr.addr_len); + + // Make sure we get IPv6 packet information as control messages. + constexpr int one = 1; + ASSERT_THAT(setsockopt(receiver_socket->get(), IPPROTO_IPV6, IPV6_RECVPKTINFO, + &one, sizeof(one)), + SyscallSucceeds()); + + // Send a packet - we don't care about the packet itself, only the returned + // IPV6_PKTINFO control message. + char send_buf[200]; + RandomizeBuffer(send_buf, sizeof(send_buf)); + ASSERT_THAT(RetryEINTR(sendto)( + sender_socket->get(), send_buf, sizeof(send_buf), 0, + AsSockAddr(&receiver_addr.addr), receiver_addr.addr_len), + SyscallSucceedsWithValue(sizeof(send_buf))); + + // Check that we received the packet with the packet information control + // message. + char recv_buf[sizeof(send_buf) + 1]; + in6_pktinfo received_pktinfo; + char recv_cmsg_buf[CMSG_SPACE(sizeof(received_pktinfo))]; + iovec recv_iov = { + .iov_base = recv_buf, + .iov_len = sizeof(recv_buf), + }; + msghdr recv_msg = { + .msg_iov = &recv_iov, + .msg_iovlen = 1, + .msg_control = recv_cmsg_buf, + .msg_controllen = sizeof(recv_cmsg_buf), + }; + ASSERT_THAT( + RetryEINTR(recvmsg)(receiver_socket->get(), &recv_msg, 0 /* flags */), + SyscallSucceedsWithValue(sizeof(send_buf))); + EXPECT_EQ(memcmp(send_buf, recv_buf, sizeof(send_buf)), 0); + + cmsghdr* cmsg = CMSG_FIRSTHDR(&recv_msg); + ASSERT_THAT(cmsg, NotNull()); + EXPECT_EQ(cmsg->cmsg_len, CMSG_LEN(sizeof(in6_pktinfo))); + EXPECT_EQ(cmsg->cmsg_level, IPPROTO_IPV6); + EXPECT_EQ(cmsg->cmsg_type, IPV6_PKTINFO); + // As per cmsg(3) (https://www.man7.org/linux/man-pages/man3/cmsg.3.html), + // + // CMSG_DATA() returns a pointer to the data portion of a cmsghdr. The + // pointer returned cannot be assumed to be suitably aligned for accessing + // arbitrary payload data types. Applications should not cast it to a + // pointer type matching the payload, but should instead use memcpy(3) to + // copy data to or from a suitably declared object. + memcpy(&received_pktinfo, CMSG_DATA(cmsg), sizeof(received_pktinfo)); + EXPECT_EQ( + memcmp(&received_pktinfo.ipi6_addr, + &(reinterpret_cast(&sender_addr.addr)->sin6_addr), + sizeof(received_pktinfo.ipi6_addr)), + 0); + EXPECT_EQ(received_pktinfo.ipi6_ifindex, + ASSERT_NO_ERRNO_AND_VALUE(GetLoopbackIndex())); + EXPECT_THAT(CMSG_NXTHDR(&recv_msg, cmsg), IsNull()); +} + // Test that socket will receive IP_RECVORIGDSTADDR control message. TEST_P(IPv6UDPUnboundSocketTest, SetAndReceiveIPReceiveOrigDstAddr) { auto sender = ASSERT_NO_ERRNO_AND_VALUE(NewSocket());