From 9e7a83e0f283965c6fbfa3d596421508dd088c58 Mon Sep 17 00:00:00 2001 From: Kevin Krakauer Date: Tue, 25 Aug 2020 13:41:23 -0700 Subject: remove iptables sockopt special cases iptables sockopts were kludged into an unnecessary check, this properly relegates them to the {get,set}SockOptIP functions. PiperOrigin-RevId: 328395135 --- pkg/sentry/socket/netstack/netstack.go | 137 ++++++++++++++-------------- pkg/sentry/socket/netstack/netstack_vfs2.go | 68 +------------- pkg/sentry/socket/unix/unix.go | 2 +- pkg/sentry/socket/unix/unix_vfs2.go | 2 +- test/syscalls/linux/iptables.cc | 37 +++++++- 5 files changed, 104 insertions(+), 142 deletions(-) diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 626195be2..9e2ebc7d4 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -983,53 +983,12 @@ func (s *SocketOperations) GetSockOpt(t *kernel.Task, level, name int, outPtr us return &val, nil } - if s.skType == linux.SOCK_RAW && level == linux.IPPROTO_IP { - switch name { - case linux.IPT_SO_GET_INFO: - if outLen < linux.SizeOfIPTGetinfo { - return nil, syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return nil, syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return nil, syserr.ErrNoDevice - } - info, err := netfilter.GetInfo(t, stack.(*Stack).Stack, outPtr) - if err != nil { - return nil, err - } - return &info, nil - - case linux.IPT_SO_GET_ENTRIES: - if outLen < linux.SizeOfIPTGetEntries { - return nil, syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return nil, syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return nil, syserr.ErrNoDevice - } - entries, err := netfilter.GetEntries4(t, stack.(*Stack).Stack, outPtr, outLen) - if err != nil { - return nil, err - } - return &entries, nil - - } - } - - return GetSockOpt(t, s, s.Endpoint, s.family, s.skType, level, name, outLen) + return GetSockOpt(t, s, s.Endpoint, s.family, s.skType, level, name, outPtr, outLen) } // GetSockOpt can be used to implement the linux syscall getsockopt(2) for // sockets backed by a commonEndpoint. -func GetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, family int, skType linux.SockType, level, name, outLen int) (marshal.Marshallable, *syserr.Error) { +func GetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, family int, skType linux.SockType, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { switch level { case linux.SOL_SOCKET: return getSockOptSocket(t, s, ep, family, skType, name, outLen) @@ -1041,7 +1000,7 @@ func GetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, family in return getSockOptIPv6(t, ep, name, outLen) case linux.SOL_IP: - return getSockOptIP(t, ep, name, outLen, family) + return getSockOptIP(t, s, ep, name, outPtr, outLen, family) case linux.SOL_UDP, linux.SOL_ICMPV6, @@ -1560,7 +1519,7 @@ func getSockOptIPv6(t *kernel.Task, ep commonEndpoint, name, outLen int) (marsha } // getSockOptIP implements GetSockOpt when level is SOL_IP. -func getSockOptIP(t *kernel.Task, ep commonEndpoint, name, outLen int, family int) (marshal.Marshallable, *syserr.Error) { +func getSockOptIP(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, outPtr usermem.Addr, outLen int, family int) (marshal.Marshallable, *syserr.Error) { switch name { case linux.IP_TTL: if outLen < sizeOfInt32 { @@ -1676,6 +1635,46 @@ func getSockOptIP(t *kernel.Task, ep commonEndpoint, name, outLen int, family in a, _ := ConvertAddress(linux.AF_INET, tcpip.FullAddress(v)) return a.(*linux.SockAddrInet), nil + case linux.IPT_SO_GET_INFO: + if outLen < linux.SizeOfIPTGetinfo { + return nil, syserr.ErrInvalidArgument + } + + // Only valid for raw IPv4 sockets. + if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { + return nil, syserr.ErrProtocolNotAvailable + } + + stack := inet.StackFromContext(t) + if stack == nil { + return nil, syserr.ErrNoDevice + } + info, err := netfilter.GetInfo(t, stack.(*Stack).Stack, outPtr) + if err != nil { + return nil, err + } + return &info, nil + + case linux.IPT_SO_GET_ENTRIES: + if outLen < linux.SizeOfIPTGetEntries { + return nil, syserr.ErrInvalidArgument + } + + // Only valid for raw IPv4 sockets. + if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { + return nil, syserr.ErrProtocolNotAvailable + } + + stack := inet.StackFromContext(t) + if stack == nil { + return nil, syserr.ErrNoDevice + } + entries, err := netfilter.GetEntries4(t, stack.(*Stack).Stack, outPtr, outLen) + if err != nil { + return nil, err + } + return &entries, nil + default: emitUnimplementedEventIP(t, name) } @@ -1709,29 +1708,6 @@ func (s *SocketOperations) SetSockOpt(t *kernel.Task, level int, name int, optVa return nil } - if s.skType == linux.SOCK_RAW && level == linux.SOL_IP { - switch name { - case linux.IPT_SO_SET_REPLACE: - if len(optVal) < linux.SizeOfIPTReplace { - return syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return syserr.ErrNoDevice - } - // Stack must be a netstack stack. - return netfilter.SetEntries(stack.(*Stack).Stack, optVal) - - case linux.IPT_SO_SET_ADD_COUNTERS: - // TODO(gvisor.dev/issue/170): Counter support. - return nil - } - } - return SetSockOpt(t, s, s.Endpoint, level, name, optVal) } @@ -1749,7 +1725,7 @@ func SetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, level int return setSockOptIPv6(t, ep, name, optVal) case linux.SOL_IP: - return setSockOptIP(t, ep, name, optVal) + return setSockOptIP(t, s, ep, name, optVal) case linux.SOL_UDP, linux.SOL_ICMPV6, @@ -2160,7 +2136,7 @@ func parseIntOrChar(buf []byte) (int32, *syserr.Error) { } // setSockOptIP implements SetSockOpt when level is SOL_IP. -func setSockOptIP(t *kernel.Task, ep commonEndpoint, name int, optVal []byte) *syserr.Error { +func setSockOptIP(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, optVal []byte) *syserr.Error { switch name { case linux.IP_MULTICAST_TTL: v, err := parseIntOrChar(optVal) @@ -2280,6 +2256,27 @@ func setSockOptIP(t *kernel.Task, ep commonEndpoint, name int, optVal []byte) *s } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.IPHdrIncludedOption, v != 0)) + case linux.IPT_SO_SET_REPLACE: + if len(optVal) < linux.SizeOfIPTReplace { + return syserr.ErrInvalidArgument + } + + // Only valid for raw IPv4 sockets. + if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { + return syserr.ErrProtocolNotAvailable + } + + stack := inet.StackFromContext(t) + if stack == nil { + return syserr.ErrNoDevice + } + // Stack must be a netstack stack. + return netfilter.SetEntries(stack.(*Stack).Stack, optVal) + + case linux.IPT_SO_SET_ADD_COUNTERS: + // TODO(gvisor.dev/issue/170): Counter support. + return nil + case linux.IP_ADD_SOURCE_MEMBERSHIP, linux.IP_BIND_ADDRESS_NO_PORT, linux.IP_BLOCK_SOURCE, diff --git a/pkg/sentry/socket/netstack/netstack_vfs2.go b/pkg/sentry/socket/netstack/netstack_vfs2.go index 1db8ae491..59fa4c58f 100644 --- a/pkg/sentry/socket/netstack/netstack_vfs2.go +++ b/pkg/sentry/socket/netstack/netstack_vfs2.go @@ -21,10 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/fsimpl/sockfs" - "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/socket/netfilter" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" @@ -233,48 +231,7 @@ func (s *SocketVFS2) GetSockOpt(t *kernel.Task, level, name int, outPtr usermem. return &val, nil } - if s.skType == linux.SOCK_RAW && level == linux.IPPROTO_IP { - switch name { - case linux.IPT_SO_GET_INFO: - if outLen < linux.SizeOfIPTGetinfo { - return nil, syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return nil, syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return nil, syserr.ErrNoDevice - } - info, err := netfilter.GetInfo(t, stack.(*Stack).Stack, outPtr) - if err != nil { - return nil, err - } - return &info, nil - - case linux.IPT_SO_GET_ENTRIES: - if outLen < linux.SizeOfIPTGetEntries { - return nil, syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return nil, syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return nil, syserr.ErrNoDevice - } - entries, err := netfilter.GetEntries4(t, stack.(*Stack).Stack, outPtr, outLen) - if err != nil { - return nil, err - } - return &entries, nil - - } - } - - return GetSockOpt(t, s, s.Endpoint, s.family, s.skType, level, name, outLen) + return GetSockOpt(t, s, s.Endpoint, s.family, s.skType, level, name, outPtr, outLen) } // SetSockOpt implements the linux syscall setsockopt(2) for sockets backed by @@ -304,29 +261,6 @@ func (s *SocketVFS2) SetSockOpt(t *kernel.Task, level int, name int, optVal []by return nil } - if s.skType == linux.SOCK_RAW && level == linux.SOL_IP { - switch name { - case linux.IPT_SO_SET_REPLACE: - if len(optVal) < linux.SizeOfIPTReplace { - return syserr.ErrInvalidArgument - } - if s.family != linux.AF_INET { - return syserr.ErrInvalidArgument - } - - stack := inet.StackFromContext(t) - if stack == nil { - return syserr.ErrNoDevice - } - // Stack must be a netstack stack. - return netfilter.SetEntries(stack.(*Stack).Stack, optVal) - - case linux.IPT_SO_SET_ADD_COUNTERS: - // TODO(gvisor.dev/issue/170): Counter support. - return nil - } - } - return SetSockOpt(t, s, s.Endpoint, level, name, optVal) } diff --git a/pkg/sentry/socket/unix/unix.go b/pkg/sentry/socket/unix/unix.go index b7e8e4325..0a7a26495 100644 --- a/pkg/sentry/socket/unix/unix.go +++ b/pkg/sentry/socket/unix/unix.go @@ -194,7 +194,7 @@ func (s *SocketOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, // GetSockOpt implements the linux syscall getsockopt(2) for sockets backed by // a transport.Endpoint. func (s *SocketOperations) GetSockOpt(t *kernel.Task, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { - return netstack.GetSockOpt(t, s, s.ep, linux.AF_UNIX, s.ep.Type(), level, name, outLen) + return netstack.GetSockOpt(t, s, s.ep, linux.AF_UNIX, s.ep.Type(), level, name, outPtr, outLen) } // Listen implements the linux syscall listen(2) for sockets backed by diff --git a/pkg/sentry/socket/unix/unix_vfs2.go b/pkg/sentry/socket/unix/unix_vfs2.go index d066ef8ab..65a285b8f 100644 --- a/pkg/sentry/socket/unix/unix_vfs2.go +++ b/pkg/sentry/socket/unix/unix_vfs2.go @@ -91,7 +91,7 @@ func NewFileDescription(ep transport.Endpoint, stype linux.SockType, flags uint3 // GetSockOpt implements the linux syscall getsockopt(2) for sockets backed by // a transport.Endpoint. func (s *SocketVFS2) GetSockOpt(t *kernel.Task, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { - return netstack.GetSockOpt(t, s, s.ep, linux.AF_UNIX, s.ep.Type(), level, name, outLen) + return netstack.GetSockOpt(t, s, s.ep, linux.AF_UNIX, s.ep.Type(), level, name, outPtr, outLen) } // blockingAccept implements a blocking version of accept(2), that is, if no diff --git a/test/syscalls/linux/iptables.cc b/test/syscalls/linux/iptables.cc index 9b338d970..f1af8f097 100644 --- a/test/syscalls/linux/iptables.cc +++ b/test/syscalls/linux/iptables.cc @@ -67,12 +67,43 @@ TEST(IPTablesBasic, FailSockoptNonRaw) { struct ipt_getinfo info = {}; snprintf(info.name, XT_TABLE_MAXNAMELEN, "%s", kNatTablename); socklen_t info_size = sizeof(info); - EXPECT_THAT(getsockopt(sock, IPPROTO_IP, IPT_SO_GET_INFO, &info, &info_size), + EXPECT_THAT(getsockopt(sock, SOL_IP, IPT_SO_GET_INFO, &info, &info_size), SyscallFailsWithErrno(ENOPROTOOPT)); ASSERT_THAT(close(sock), SyscallSucceeds()); } +TEST(IPTablesBasic, GetInfoErrorPrecedence) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int sock; + ASSERT_THAT(sock = socket(AF_INET, SOCK_DGRAM, 0), SyscallSucceeds()); + + // When using the wrong type of socket and a too-short optlen, we should get + // EINVAL. + struct ipt_getinfo info = {}; + snprintf(info.name, XT_TABLE_MAXNAMELEN, "%s", kNatTablename); + socklen_t info_size = sizeof(info) - 1; + ASSERT_THAT(getsockopt(sock, SOL_IP, IPT_SO_GET_INFO, &info, &info_size), + SyscallFailsWithErrno(EINVAL)); +} + +TEST(IPTablesBasic, GetEntriesErrorPrecedence) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int sock; + ASSERT_THAT(sock = socket(AF_INET, SOCK_DGRAM, 0), SyscallSucceeds()); + + // When using the wrong type of socket and a too-short optlen, we should get + // EINVAL. + struct ipt_get_entries entries = {}; + socklen_t entries_size = sizeof(struct ipt_get_entries) - 1; + snprintf(entries.name, XT_TABLE_MAXNAMELEN, "%s", kNatTablename); + ASSERT_THAT( + getsockopt(sock, SOL_IP, IPT_SO_GET_ENTRIES, &entries, &entries_size), + SyscallFailsWithErrno(EINVAL)); +} + // Fixture for iptables tests. class IPTablesTest : public ::testing::Test { protected: @@ -112,7 +143,7 @@ TEST_F(IPTablesTest, InitialState) { struct ipt_getinfo info = {}; snprintf(info.name, XT_TABLE_MAXNAMELEN, "%s", kNatTablename); socklen_t info_size = sizeof(info); - ASSERT_THAT(getsockopt(s_, IPPROTO_IP, IPT_SO_GET_INFO, &info, &info_size), + ASSERT_THAT(getsockopt(s_, SOL_IP, IPT_SO_GET_INFO, &info, &info_size), SyscallSucceeds()); // The nat table supports PREROUTING, and OUTPUT. @@ -148,7 +179,7 @@ TEST_F(IPTablesTest, InitialState) { snprintf(entries->name, XT_TABLE_MAXNAMELEN, "%s", kNatTablename); entries->size = info.size; ASSERT_THAT( - getsockopt(s_, IPPROTO_IP, IPT_SO_GET_ENTRIES, entries, &entries_size), + getsockopt(s_, SOL_IP, IPT_SO_GET_ENTRIES, entries, &entries_size), SyscallSucceeds()); // Verify the name and size. -- cgit v1.2.3