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Diffstat (limited to 'test/syscalls/linux/raw_socket.cc')
| -rw-r--r-- | test/syscalls/linux/raw_socket.cc | 819 |
1 files changed, 819 insertions, 0 deletions
diff --git a/test/syscalls/linux/raw_socket.cc b/test/syscalls/linux/raw_socket.cc new file mode 100644 index 000000000..05c4ed03f --- /dev/null +++ b/test/syscalls/linux/raw_socket.cc @@ -0,0 +1,819 @@ +// Copyright 2019 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. + +#include <linux/capability.h> +#include <netinet/in.h> +#include <netinet/ip.h> +#include <netinet/ip6.h> +#include <netinet/ip_icmp.h> +#include <poll.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <unistd.h> +#include <algorithm> + +#include "gtest/gtest.h" +#include "test/syscalls/linux/socket_test_util.h" +#include "test/syscalls/linux/unix_domain_socket_test_util.h" +#include "test/util/capability_util.h" +#include "test/util/file_descriptor.h" +#include "test/util/test_util.h" + +// Note: in order to run these tests, /proc/sys/net/ipv4/ping_group_range will +// need to be configured to let the superuser create ping sockets (see icmp(7)). + +namespace gvisor { +namespace testing { + +namespace { + +// Fixture for tests parameterized by protocol. +class RawSocketTest : public ::testing::TestWithParam<std::tuple<int, int>> { + protected: + // Creates a socket to be used in tests. + void SetUp() override; + + // Closes the socket created by SetUp(). + void TearDown() override; + + // Sends buf via s_. + void SendBuf(const char* buf, int buf_len); + + // Reads from s_ into recv_buf. + void ReceiveBuf(char* recv_buf, size_t recv_buf_len); + + void ReceiveBufFrom(int sock, char* recv_buf, size_t recv_buf_len); + + int Protocol() { return std::get<0>(GetParam()); } + + int Family() { return std::get<1>(GetParam()); } + + socklen_t AddrLen() { + if (Family() == AF_INET) { + return sizeof(sockaddr_in); + } + return sizeof(sockaddr_in6); + } + + int HdrLen() { + if (Family() == AF_INET) { + return sizeof(struct iphdr); + } + // IPv6 raw sockets don't include the header. + return 0; + } + + // The socket used for both reading and writing. + int s_; + + // The loopback address. + struct sockaddr_storage addr_; +}; + +void RawSocketTest::SetUp() { + if (!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))) { + ASSERT_THAT(socket(Family(), SOCK_RAW, Protocol()), + SyscallFailsWithErrno(EPERM)); + GTEST_SKIP(); + } + + ASSERT_THAT(s_ = socket(Family(), SOCK_RAW, Protocol()), SyscallSucceeds()); + + addr_ = {}; + + // We don't set ports because raw sockets don't have a notion of ports. + if (Family() == AF_INET) { + struct sockaddr_in* sin = reinterpret_cast<struct sockaddr_in*>(&addr_); + sin->sin_family = AF_INET; + sin->sin_addr.s_addr = htonl(INADDR_LOOPBACK); + } else { + struct sockaddr_in6* sin6 = reinterpret_cast<struct sockaddr_in6*>(&addr_); + sin6->sin6_family = AF_INET6; + sin6->sin6_addr = in6addr_loopback; + } +} + +void RawSocketTest::TearDown() { + // TearDown will be run even if we skip the test. + if (ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))) { + EXPECT_THAT(close(s_), SyscallSucceeds()); + } +} + +// We should be able to create multiple raw sockets for the same protocol. +// BasicRawSocket::Setup creates the first one, so we only have to create one +// more here. +TEST_P(RawSocketTest, MultipleCreation) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int s2; + ASSERT_THAT(s2 = socket(Family(), SOCK_RAW, Protocol()), SyscallSucceeds()); + + ASSERT_THAT(close(s2), SyscallSucceeds()); +} + +// Test that shutting down an unconnected socket fails. +TEST_P(RawSocketTest, FailShutdownWithoutConnect) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT(shutdown(s_, SHUT_WR), SyscallFailsWithErrno(ENOTCONN)); + ASSERT_THAT(shutdown(s_, SHUT_RD), SyscallFailsWithErrno(ENOTCONN)); +} + +// Shutdown is a no-op for raw sockets (and datagram sockets in general). +TEST_P(RawSocketTest, ShutdownWriteNoop) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + ASSERT_THAT(shutdown(s_, SHUT_WR), SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "noop"; + ASSERT_THAT(RetryEINTR(write)(s_, kBuf, sizeof(kBuf)), + SyscallSucceedsWithValue(sizeof(kBuf))); +} + +// Shutdown is a no-op for raw sockets (and datagram sockets in general). +TEST_P(RawSocketTest, ShutdownReadNoop) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + ASSERT_THAT(shutdown(s_, SHUT_RD), SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "gdg"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + std::vector<char> c(sizeof(kBuf) + HdrLen()); + ASSERT_THAT(read(s_, c.data(), c.size()), SyscallSucceedsWithValue(c.size())); +} + +// Test that listen() fails. +TEST_P(RawSocketTest, FailListen) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT(listen(s_, 1), SyscallFailsWithErrno(ENOTSUP)); +} + +// Test that accept() fails. +TEST_P(RawSocketTest, FailAccept) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + struct sockaddr saddr; + socklen_t addrlen; + ASSERT_THAT(accept(s_, &saddr, &addrlen), SyscallFailsWithErrno(ENOTSUP)); +} + +// Test that getpeername() returns nothing before connect(). +TEST_P(RawSocketTest, FailGetPeerNameBeforeConnect) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + struct sockaddr saddr; + socklen_t addrlen = sizeof(saddr); + ASSERT_THAT(getpeername(s_, &saddr, &addrlen), + SyscallFailsWithErrno(ENOTCONN)); +} + +// Test that getpeername() returns something after connect(). +TEST_P(RawSocketTest, GetPeerName) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + struct sockaddr saddr; + socklen_t addrlen = sizeof(saddr); + ASSERT_THAT(getpeername(s_, &saddr, &addrlen), + SyscallFailsWithErrno(ENOTCONN)); + ASSERT_GT(addrlen, 0); +} + +// Test that the socket is writable immediately. +TEST_P(RawSocketTest, PollWritableImmediately) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + struct pollfd pfd = {}; + pfd.fd = s_; + pfd.events = POLLOUT; + ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, 10000), SyscallSucceedsWithValue(1)); +} + +// Test that the socket isn't readable before receiving anything. +TEST_P(RawSocketTest, PollNotReadableInitially) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Try to receive data with MSG_DONTWAIT, which returns immediately if there's + // nothing to be read. + char buf[117]; + ASSERT_THAT(RetryEINTR(recv)(s_, buf, sizeof(buf), MSG_DONTWAIT), + SyscallFailsWithErrno(EAGAIN)); +} + +// Test that the socket becomes readable once something is written to it. +TEST_P(RawSocketTest, PollTriggeredOnWrite) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Write something so that there's data to be read. + // Arbitrary. + constexpr char kBuf[] = "JP5"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + struct pollfd pfd = {}; + pfd.fd = s_; + pfd.events = POLLIN; + ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, 10000), SyscallSucceedsWithValue(1)); +} + +// Test that we can connect() to a valid IP (loopback). +TEST_P(RawSocketTest, ConnectToLoopback) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); +} + +// Test that calling send() without connect() fails. +TEST_P(RawSocketTest, SendWithoutConnectFails) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Arbitrary. + constexpr char kBuf[] = "Endgame was good"; + ASSERT_THAT(send(s_, kBuf, sizeof(kBuf), 0), + SyscallFailsWithErrno(EDESTADDRREQ)); +} + +// Bind to localhost. +TEST_P(RawSocketTest, BindToLocalhost) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + bind(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); +} + +// Bind to a different address. +TEST_P(RawSocketTest, BindToInvalid) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + struct sockaddr_storage bind_addr = addr_; + if (Family() == AF_INET) { + struct sockaddr_in* sin = reinterpret_cast<struct sockaddr_in*>(&bind_addr); + sin->sin_addr = {1}; // 1.0.0.0 - An address that we can't bind to. + } else { + struct sockaddr_in6* sin6 = + reinterpret_cast<struct sockaddr_in6*>(&bind_addr); + memset(&sin6->sin6_addr.s6_addr, 0, sizeof(sin6->sin6_addr.s6_addr)); + sin6->sin6_addr.s6_addr[0] = 1; // 1: - An address that we can't bind to. + } + ASSERT_THAT(bind(s_, reinterpret_cast<struct sockaddr*>(&bind_addr), + AddrLen()), SyscallFailsWithErrno(EADDRNOTAVAIL)); +} + +// Send and receive an packet. +TEST_P(RawSocketTest, SendAndReceive) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Arbitrary. + constexpr char kBuf[] = "TB12"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ(memcmp(recv_buf.data() + HdrLen(), kBuf, sizeof(kBuf)), 0); +} + +// We should be able to create multiple raw sockets for the same protocol and +// receive the same packet on both. +TEST_P(RawSocketTest, MultipleSocketReceive) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int s2; + ASSERT_THAT(s2 = socket(Family(), SOCK_RAW, Protocol()), SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "TB10"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + // Receive it on socket 1. + std::vector<char> recv_buf1(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf1.data(), recv_buf1.size())); + + // Receive it on socket 2. + std::vector<char> recv_buf2(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBufFrom(s2, recv_buf2.data(), + recv_buf2.size())); + + EXPECT_EQ(memcmp(recv_buf1.data() + HdrLen(), + recv_buf2.data() + HdrLen(), sizeof(kBuf)), + 0); + + ASSERT_THAT(close(s2), SyscallSucceeds()); +} + +// Test that connect sends packets to the right place. +TEST_P(RawSocketTest, SendAndReceiveViaConnect) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "JH4"; + ASSERT_THAT(send(s_, kBuf, sizeof(kBuf), 0), + SyscallSucceedsWithValue(sizeof(kBuf))); + + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ(memcmp(recv_buf.data() + HdrLen(), kBuf, sizeof(kBuf)), 0); +} + +// Bind to localhost, then send and receive packets. +TEST_P(RawSocketTest, BindSendAndReceive) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + bind(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "DR16"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ(memcmp(recv_buf.data() + HdrLen(), kBuf, sizeof(kBuf)), 0); +} + +// Bind and connect to localhost and send/receive packets. +TEST_P(RawSocketTest, BindConnectSendAndReceive) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + bind(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + + // Arbitrary. + constexpr char kBuf[] = "DG88"; + ASSERT_NO_FATAL_FAILURE(SendBuf(kBuf, sizeof(kBuf))); + + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(sizeof(kBuf) + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ(memcmp(recv_buf.data() + HdrLen(), kBuf, sizeof(kBuf)), 0); +} + +// Check that setting SO_RCVBUF below min is clamped to the minimum +// receive buffer size. +TEST_P(RawSocketTest, SetSocketRecvBufBelowMin) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Discover minimum receive buf size by trying to set it to zero. + // See: + // https://github.com/torvalds/linux/blob/a5dc8300df75e8b8384b4c82225f1e4a0b4d9b55/net/core/sock.c#L820 + constexpr int kRcvBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + int min = 0; + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &min, &min_len), + SyscallSucceeds()); + + // Linux doubles the value so let's use a value that when doubled will still + // be smaller than min. + int below_min = min / 2 - 1; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &below_min, sizeof(below_min)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &val, &val_len), + SyscallSucceeds()); + + ASSERT_EQ(min, val); +} + +// Check that setting SO_RCVBUF above max is clamped to the maximum +// receive buffer size. +TEST_P(RawSocketTest, SetSocketRecvBufAboveMax) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Discover max buf size by trying to set the largest possible buffer size. + constexpr int kRcvBufSz = 0xffffffff; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + int max = 0; + socklen_t max_len = sizeof(max); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &max, &max_len), + SyscallSucceeds()); + + int above_max = max + 1; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &above_max, sizeof(above_max)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &val, &val_len), + SyscallSucceeds()); + ASSERT_EQ(max, val); +} + +// Check that setting SO_RCVBUF min <= kRcvBufSz <= max is honored. +TEST_P(RawSocketTest, SetSocketRecvBuf) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int max = 0; + int min = 0; + { + // Discover max buf size by trying to set a really large buffer size. + constexpr int kRcvBufSz = 0xffffffff; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + max = 0; + socklen_t max_len = sizeof(max); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &max, &max_len), + SyscallSucceeds()); + } + + { + // Discover minimum buffer size by trying to set a zero size receive buffer + // size. + // See: + // https://github.com/torvalds/linux/blob/a5dc8300df75e8b8384b4c82225f1e4a0b4d9b55/net/core/sock.c#L820 + constexpr int kRcvBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &min, &min_len), + SyscallSucceeds()); + } + + int quarter_sz = min + (max - min) / 4; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &quarter_sz, sizeof(quarter_sz)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &val, &val_len), + SyscallSucceeds()); + + // Linux doubles the value set by SO_SNDBUF/SO_RCVBUF. + // TODO(gvisor.dev/issue/2926): Remove when Netstack matches linux behavior. + if (!IsRunningOnGvisor()) { + quarter_sz *= 2; + } + ASSERT_EQ(quarter_sz, val); +} + +// Check that setting SO_SNDBUF below min is clamped to the minimum +// receive buffer size. +TEST_P(RawSocketTest, SetSocketSendBufBelowMin) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Discover minimum buffer size by trying to set it to zero. + constexpr int kSndBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &kSndBufSz, sizeof(kSndBufSz)), + SyscallSucceeds()); + + int min = 0; + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &min, &min_len), + SyscallSucceeds()); + + // Linux doubles the value so let's use a value that when doubled will still + // be smaller than min. + int below_min = min / 2 - 1; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &below_min, sizeof(below_min)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &val, &val_len), + SyscallSucceeds()); + + ASSERT_EQ(min, val); +} + +// Check that setting SO_SNDBUF above max is clamped to the maximum +// send buffer size. +TEST_P(RawSocketTest, SetSocketSendBufAboveMax) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + // Discover maximum buffer size by trying to set it to a large value. + constexpr int kSndBufSz = 0xffffffff; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &kSndBufSz, sizeof(kSndBufSz)), + SyscallSucceeds()); + + int max = 0; + socklen_t max_len = sizeof(max); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &max, &max_len), + SyscallSucceeds()); + + int above_max = max + 1; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &above_max, sizeof(above_max)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &val, &val_len), + SyscallSucceeds()); + ASSERT_EQ(max, val); +} + +// Check that setting SO_SNDBUF min <= kSndBufSz <= max is honored. +TEST_P(RawSocketTest, SetSocketSendBuf) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int max = 0; + int min = 0; + { + // Discover maximum buffer size by trying to set it to a large value. + constexpr int kSndBufSz = 0xffffffff; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &kSndBufSz, sizeof(kSndBufSz)), + SyscallSucceeds()); + + max = 0; + socklen_t max_len = sizeof(max); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &max, &max_len), + SyscallSucceeds()); + } + + { + // Discover minimum buffer size by trying to set it to zero. + constexpr int kSndBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &kSndBufSz, sizeof(kSndBufSz)), + SyscallSucceeds()); + + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &min, &min_len), + SyscallSucceeds()); + } + + int quarter_sz = min + (max - min) / 4; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_SNDBUF, &quarter_sz, sizeof(quarter_sz)), + SyscallSucceeds()); + + int val = 0; + socklen_t val_len = sizeof(val); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_SNDBUF, &val, &val_len), + SyscallSucceeds()); + + // Linux doubles the value set by SO_SNDBUF/SO_RCVBUF. + // TODO(gvisor.dev/issue/2926): Remove the gvisor special casing when Netstack + // matches linux behavior. + if (!IsRunningOnGvisor()) { + quarter_sz *= 2; + } + + ASSERT_EQ(quarter_sz, val); +} + +// Test that receive buffer limits are not enforced when the recv buffer is +// empty. +TEST_P(RawSocketTest, RecvBufLimitsEmptyRecvBuffer) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + bind(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + + int min = 0; + { + // Discover minimum buffer size by trying to set it to zero. + constexpr int kRcvBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &min, &min_len), + SyscallSucceeds()); + } + + { + // Send data of size min and verify that it's received. + std::vector<char> buf(min); + RandomizeBuffer(buf.data(), buf.size()); + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(buf.size() + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ( + memcmp(recv_buf.data() + HdrLen(), buf.data(), buf.size()), + 0); + } + + { + // Send data of size min + 1 and verify that its received. Both linux and + // Netstack accept a dgram that exceeds rcvBuf limits if the receive buffer + // is currently empty. + std::vector<char> buf(min + 1); + RandomizeBuffer(buf.data(), buf.size()); + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(buf.size() + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ( + memcmp(recv_buf.data() + HdrLen(), buf.data(), buf.size()), + 0); + } +} + +TEST_P(RawSocketTest, RecvBufLimits) { + // TCP stack generates RSTs for unknown endpoints and it complicates the test + // as we have to deal with the RST packets as well. For testing the raw socket + // endpoints buffer limit enforcement we can just test for UDP. + // + // We don't use SKIP_IF here because root_test_runner explicitly fails if a + // test is skipped. + if (Protocol() == IPPROTO_TCP) { + return; + } + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + ASSERT_THAT( + bind(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + ASSERT_THAT( + connect(s_, reinterpret_cast<struct sockaddr*>(&addr_), AddrLen()), + SyscallSucceeds()); + + int min = 0; + { + // Discover minimum buffer size by trying to set it to zero. + constexpr int kRcvBufSz = 0; + ASSERT_THAT( + setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &kRcvBufSz, sizeof(kRcvBufSz)), + SyscallSucceeds()); + + socklen_t min_len = sizeof(min); + ASSERT_THAT(getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &min, &min_len), + SyscallSucceeds()); + } + + // Now set the limit to min * 2. + int new_rcv_buf_sz = min * 4; + if (!IsRunningOnGvisor()) { + // Linux doubles the value specified so just set to min. + new_rcv_buf_sz = min * 2; + } + + ASSERT_THAT(setsockopt(s_, SOL_SOCKET, SO_RCVBUF, &new_rcv_buf_sz, + sizeof(new_rcv_buf_sz)), + SyscallSucceeds()); + int rcv_buf_sz = 0; + { + socklen_t rcv_buf_len = sizeof(rcv_buf_sz); + ASSERT_THAT( + getsockopt(s_, SOL_SOCKET, SO_RCVBUF, &rcv_buf_sz, &rcv_buf_len), + SyscallSucceeds()); + } + + // Set a receive timeout so that we don't block forever on reads if the test + // fails. + struct timeval tv { + .tv_sec = 1, .tv_usec = 0, + }; + ASSERT_THAT(setsockopt(s_, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)), + SyscallSucceeds()); + + { + std::vector<char> buf(min); + RandomizeBuffer(buf.data(), buf.size()); + + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + int sent = 4; + if (IsRunningOnGvisor()) { + // Linux seems to drop the 4th packet even though technically it should + // fit in the receive buffer. + ASSERT_NO_FATAL_FAILURE(SendBuf(buf.data(), buf.size())); + sent++; + } + + // Verify that the expected number of packets are available to be read. + for (int i = 0; i < sent - 1; i++) { + // Receive the packet and make sure it's identical. + std::vector<char> recv_buf(buf.size() + HdrLen()); + ASSERT_NO_FATAL_FAILURE(ReceiveBuf(recv_buf.data(), recv_buf.size())); + EXPECT_EQ(memcmp(recv_buf.data() + HdrLen(), buf.data(), + buf.size()), + 0); + } + + // Assert that the last packet is dropped because the receive buffer should + // be full after the first four packets. + std::vector<char> recv_buf(buf.size() + HdrLen()); + struct iovec iov = {}; + iov.iov_base = static_cast<void*>(const_cast<char*>(recv_buf.data())); + iov.iov_len = buf.size(); + struct msghdr msg = {}; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = NULL; + msg.msg_controllen = 0; + msg.msg_flags = 0; + ASSERT_THAT(RetryEINTR(recvmsg)(s_, &msg, MSG_DONTWAIT), + SyscallFailsWithErrno(EAGAIN)); + } +} + +void RawSocketTest::SendBuf(const char* buf, int buf_len) { + // It's safe to use const_cast here because sendmsg won't modify the iovec or + // address. + struct iovec iov = {}; + iov.iov_base = static_cast<void*>(const_cast<char*>(buf)); + iov.iov_len = static_cast<size_t>(buf_len); + struct msghdr msg = {}; + msg.msg_name = static_cast<void*>(&addr_); + msg.msg_namelen = AddrLen(); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = NULL; + msg.msg_controllen = 0; + msg.msg_flags = 0; + ASSERT_THAT(sendmsg(s_, &msg, 0), SyscallSucceedsWithValue(buf_len)); +} + +void RawSocketTest::ReceiveBuf(char* recv_buf, size_t recv_buf_len) { + ASSERT_NO_FATAL_FAILURE(ReceiveBufFrom(s_, recv_buf, recv_buf_len)); +} + +void RawSocketTest::ReceiveBufFrom(int sock, char* recv_buf, + size_t recv_buf_len) { + ASSERT_NO_FATAL_FAILURE(RecvNoCmsg(sock, recv_buf, recv_buf_len)); +} + +INSTANTIATE_TEST_SUITE_P(AllInetTests, RawSocketTest, + ::testing::Combine( + ::testing::Values(IPPROTO_TCP, IPPROTO_UDP), + ::testing::Values(AF_INET, AF_INET6))); + +// AF_INET6+SOCK_RAW+IPPROTO_RAW sockets can be created, but not written to. +TEST(RawSocketTest, IPv6ProtoRaw) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); + + int sock; + ASSERT_THAT(sock = socket(AF_INET6, SOCK_RAW, IPPROTO_RAW), + SyscallSucceeds()); + + // Verify that writing yields EINVAL. + char buf[] = "This is such a weird little edge case"; + struct sockaddr_in6 sin6 = {}; + sin6.sin6_family = AF_INET6; + sin6.sin6_addr = in6addr_loopback; + ASSERT_THAT(sendto(sock, buf, sizeof(buf), 0 /* flags */, + reinterpret_cast<struct sockaddr*>(&sin6), sizeof(sin6)), + SyscallFailsWithErrno(EINVAL)); +} + +} // namespace + +} // namespace testing +} // namespace gvisor |