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-rw-r--r--test/syscalls/linux/BUILD18
-rw-r--r--test/syscalls/linux/packet_socket_raw.cc314
2 files changed, 332 insertions, 0 deletions
diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD
index e2b0716ef..ca4344139 100644
--- a/test/syscalls/linux/BUILD
+++ b/test/syscalls/linux/BUILD
@@ -1227,6 +1227,24 @@ cc_binary(
)
cc_binary(
+ name = "packet_socket_raw_test",
+ testonly = 1,
+ srcs = ["packet_socket_raw.cc"],
+ linkstatic = 1,
+ deps = [
+ ":socket_test_util",
+ ":unix_domain_socket_test_util",
+ "//test/util:capability_util",
+ "//test/util:file_descriptor",
+ "//test/util:test_main",
+ "//test/util:test_util",
+ "@com_google_absl//absl/base:core_headers",
+ "@com_google_absl//absl/base:endian",
+ "@com_google_googletest//:gtest",
+ ],
+)
+
+cc_binary(
name = "packet_socket_test",
testonly = 1,
srcs = ["packet_socket.cc"],
diff --git a/test/syscalls/linux/packet_socket_raw.cc b/test/syscalls/linux/packet_socket_raw.cc
new file mode 100644
index 000000000..9e96460ee
--- /dev/null
+++ b/test/syscalls/linux/packet_socket_raw.cc
@@ -0,0 +1,314 @@
+// 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 <arpa/inet.h>
+#include <linux/capability.h>
+#include <linux/if_arp.h>
+#include <linux/if_packet.h>
+#include <net/ethernet.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/udp.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "gtest/gtest.h"
+#include "absl/base/internal/endian.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"
+
+// Some of these tests involve sending packets via AF_PACKET sockets and the
+// loopback interface. Because AF_PACKET circumvents so much of the networking
+// stack, Linux sees these packets as "martian", i.e. they claim to be to/from
+// localhost but don't have the usual associated data. Thus Linux drops them by
+// default. You can see where this happens by following the code at:
+//
+// - net/ipv4/ip_input.c:ip_rcv_finish, which calls
+// - net/ipv4/route.c:ip_route_input_noref, which calls
+// - net/ipv4/route.c:ip_route_input_slow, which finds and drops martian
+// packets.
+//
+// To tell Linux not to drop these packets, you need to tell it to accept our
+// funny packets (which are completely valid and correct, but lack associated
+// in-kernel data because we use AF_PACKET):
+//
+// echo 1 >> /proc/sys/net/ipv4/conf/lo/accept_local
+// echo 1 >> /proc/sys/net/ipv4/conf/lo/route_localnet
+//
+// These tests require CAP_NET_RAW to run.
+
+// TODO(gvisor.dev/issue/173): gVisor support.
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+constexpr char kMessage[] = "soweoneul malhaebwa";
+constexpr in_port_t kPort = 0x409c; // htons(40000)
+
+// Send kMessage via sock to loopback
+void SendUDPMessage(int sock) {
+ struct sockaddr_in dest = {};
+ dest.sin_port = kPort;
+ dest.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+ dest.sin_family = AF_INET;
+ EXPECT_THAT(sendto(sock, kMessage, sizeof(kMessage), 0,
+ reinterpret_cast<struct sockaddr*>(&dest), sizeof(dest)),
+ SyscallSucceedsWithValue(sizeof(kMessage)));
+}
+
+//
+// Raw tests. Packets sent with raw AF_PACKET sockets always include link layer
+// headers.
+//
+
+// Tests for "raw" (SOCK_RAW) packet(7) sockets.
+class RawPacketTest : public ::testing::TestWithParam<int> {
+ protected:
+ // Creates a socket to be used in tests.
+ void SetUp() override;
+
+ // Closes the socket created by SetUp().
+ void TearDown() override;
+
+ // Gets the device index of the loopback device.
+ int GetLoopbackIndex();
+
+ // The socket used for both reading and writing.
+ int socket_;
+};
+
+void RawPacketTest::SetUp() {
+ SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW)));
+ SKIP_IF(IsRunningOnGvisor());
+
+ if (!IsRunningOnGvisor()) {
+ FileDescriptor acceptLocal = ASSERT_NO_ERRNO_AND_VALUE(
+ Open("/proc/sys/net/ipv4/conf/lo/accept_local", O_RDONLY));
+ FileDescriptor routeLocalnet = ASSERT_NO_ERRNO_AND_VALUE(
+ Open("/proc/sys/net/ipv4/conf/lo/route_localnet", O_RDONLY));
+ char enabled;
+ ASSERT_THAT(read(acceptLocal.get(), &enabled, 1),
+ SyscallSucceedsWithValue(1));
+ ASSERT_EQ(enabled, '1');
+ ASSERT_THAT(read(routeLocalnet.get(), &enabled, 1),
+ SyscallSucceedsWithValue(1));
+ ASSERT_EQ(enabled, '1');
+ }
+
+ ASSERT_THAT(socket_ = socket(AF_PACKET, SOCK_RAW, htons(GetParam())),
+ SyscallSucceeds());
+}
+
+void RawPacketTest::TearDown() {
+ SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW)));
+ SKIP_IF(IsRunningOnGvisor());
+
+ EXPECT_THAT(close(socket_), SyscallSucceeds());
+}
+
+int RawPacketTest::GetLoopbackIndex() {
+ struct ifreq ifr;
+ snprintf(ifr.ifr_name, IFNAMSIZ, "lo");
+ EXPECT_THAT(ioctl(socket_, SIOCGIFINDEX, &ifr), SyscallSucceeds());
+ EXPECT_NE(ifr.ifr_ifindex, 0);
+ return ifr.ifr_ifindex;
+}
+
+// Receive via a packet socket.
+TEST_P(RawPacketTest, Receive) {
+ SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW)));
+ SKIP_IF(IsRunningOnGvisor());
+
+ // Let's use a simple IP payload: a UDP datagram.
+ FileDescriptor udp_sock =
+ ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_INET, SOCK_DGRAM, 0));
+ SendUDPMessage(udp_sock.get());
+
+ // Wait for the socket to become readable.
+ struct pollfd pfd = {};
+ pfd.fd = socket_;
+ pfd.events = POLLIN;
+ EXPECT_THAT(RetryEINTR(poll)(&pfd, 1, 2000), SyscallSucceedsWithValue(1));
+
+ // Read and verify the data.
+ constexpr size_t packet_size = sizeof(struct ethhdr) + sizeof(struct iphdr) +
+ sizeof(struct udphdr) + sizeof(kMessage);
+ char buf[64];
+ struct sockaddr_ll src = {};
+ socklen_t src_len = sizeof(src);
+ ASSERT_THAT(recvfrom(socket_, buf, sizeof(buf), 0,
+ reinterpret_cast<struct sockaddr*>(&src), &src_len),
+ SyscallSucceedsWithValue(packet_size));
+ // sizeof(src) is the size of a struct sockaddr_ll. sockaddr_ll ends with an 8
+ // byte physical address field, but ethernet (MAC) addresses only use 6 bytes.
+ // Thus src_len should get modified to be 2 less than the size of sockaddr_ll.
+ ASSERT_EQ(src_len, sizeof(src) - 2);
+
+ // Verify the source address.
+ EXPECT_EQ(src.sll_family, AF_PACKET);
+ EXPECT_EQ(src.sll_protocol, htons(ETH_P_IP));
+ EXPECT_EQ(src.sll_ifindex, GetLoopbackIndex());
+ EXPECT_EQ(src.sll_hatype, ARPHRD_LOOPBACK);
+ EXPECT_EQ(src.sll_halen, ETH_ALEN);
+ // This came from the loopback device, so the address is all 0s.
+ for (int i = 0; i < src.sll_halen; i++) {
+ EXPECT_EQ(src.sll_addr[i], 0);
+ }
+
+ // Verify the ethernet header. We memcpy to deal with pointer alignment.
+ struct ethhdr eth = {};
+ memcpy(&eth, buf, sizeof(eth));
+ // The destination and source address should be 0, for loopback.
+ for (int i = 0; i < ETH_ALEN; i++) {
+ EXPECT_EQ(eth.h_dest[i], 0);
+ EXPECT_EQ(eth.h_source[i], 0);
+ }
+ EXPECT_EQ(eth.h_proto, htons(ETH_P_IP));
+
+ // Verify the IP header. We memcpy to deal with pointer aligment.
+ struct iphdr ip = {};
+ memcpy(&ip, buf + sizeof(ethhdr), sizeof(ip));
+ EXPECT_EQ(ip.ihl, 5);
+ EXPECT_EQ(ip.version, 4);
+ EXPECT_EQ(ip.tot_len, htons(packet_size - sizeof(eth)));
+ EXPECT_EQ(ip.protocol, IPPROTO_UDP);
+ EXPECT_EQ(ip.daddr, htonl(INADDR_LOOPBACK));
+ EXPECT_EQ(ip.saddr, htonl(INADDR_LOOPBACK));
+
+ // Verify the UDP header. We memcpy to deal with pointer aligment.
+ struct udphdr udp = {};
+ memcpy(&udp, buf + sizeof(eth) + sizeof(iphdr), sizeof(udp));
+ EXPECT_EQ(udp.dest, kPort);
+ EXPECT_EQ(udp.len, htons(sizeof(udphdr) + sizeof(kMessage)));
+
+ // Verify the payload.
+ char* payload = reinterpret_cast<char*>(buf + sizeof(eth) + sizeof(iphdr) +
+ sizeof(udphdr));
+ EXPECT_EQ(strncmp(payload, kMessage, sizeof(kMessage)), 0);
+}
+
+// Send via a packet socket.
+TEST_P(RawPacketTest, Send) {
+ SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW)));
+ SKIP_IF(IsRunningOnGvisor());
+
+ // Let's send a UDP packet and receive it using a regular UDP socket.
+ FileDescriptor udp_sock =
+ ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_INET, SOCK_DGRAM, 0));
+ struct sockaddr_in bind_addr = {};
+ bind_addr.sin_family = AF_INET;
+ bind_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+ bind_addr.sin_port = kPort;
+ ASSERT_THAT(
+ bind(udp_sock.get(), reinterpret_cast<struct sockaddr*>(&bind_addr),
+ sizeof(bind_addr)),
+ SyscallSucceeds());
+
+ // Set up the destination physical address.
+ struct sockaddr_ll dest = {};
+ dest.sll_family = AF_PACKET;
+ dest.sll_halen = ETH_ALEN;
+ dest.sll_ifindex = GetLoopbackIndex();
+ dest.sll_protocol = htons(ETH_P_IP);
+ // We're sending to the loopback device, so the address is all 0s.
+ memset(dest.sll_addr, 0x00, ETH_ALEN);
+
+ // Set up the ethernet header. The kernel takes care of the footer.
+ // We're sending to and from hardware address 0 (loopback).
+ struct ethhdr eth = {};
+ eth.h_proto = htons(ETH_P_IP);
+
+ // Set up the IP header.
+ struct iphdr iphdr = {};
+ iphdr.ihl = 5;
+ iphdr.version = 4;
+ iphdr.tos = 0;
+ iphdr.tot_len =
+ htons(sizeof(struct iphdr) + sizeof(struct udphdr) + sizeof(kMessage));
+ // Get a pseudo-random ID. If we clash with an in-use ID the test will fail,
+ // but we have no way of getting an ID we know to be good.
+ srand(*reinterpret_cast<unsigned int*>(&iphdr));
+ iphdr.id = rand();
+ // Linux sets this bit ("do not fragment") for small packets.
+ iphdr.frag_off = 1 << 6;
+ iphdr.ttl = 64;
+ iphdr.protocol = IPPROTO_UDP;
+ iphdr.daddr = htonl(INADDR_LOOPBACK);
+ iphdr.saddr = htonl(INADDR_LOOPBACK);
+ iphdr.check = IPChecksum(iphdr);
+
+ // Set up the UDP header.
+ struct udphdr udphdr = {};
+ udphdr.source = kPort;
+ udphdr.dest = kPort;
+ udphdr.len = htons(sizeof(udphdr) + sizeof(kMessage));
+ udphdr.check = UDPChecksum(iphdr, udphdr, kMessage, sizeof(kMessage));
+
+ // Copy both headers and the payload into our packet buffer.
+ char
+ send_buf[sizeof(eth) + sizeof(iphdr) + sizeof(udphdr) + sizeof(kMessage)];
+ memcpy(send_buf, &eth, sizeof(eth));
+ memcpy(send_buf + sizeof(ethhdr), &iphdr, sizeof(iphdr));
+ memcpy(send_buf + sizeof(ethhdr) + sizeof(iphdr), &udphdr, sizeof(udphdr));
+ memcpy(send_buf + sizeof(ethhdr) + sizeof(iphdr) + sizeof(udphdr), kMessage,
+ sizeof(kMessage));
+
+ // Send it.
+ ASSERT_THAT(sendto(socket_, send_buf, sizeof(send_buf), 0,
+ reinterpret_cast<struct sockaddr*>(&dest), sizeof(dest)),
+ SyscallSucceedsWithValue(sizeof(send_buf)));
+
+ // Wait for the packet to become available on both sockets.
+ struct pollfd pfd = {};
+ pfd.fd = udp_sock.get();
+ pfd.events = POLLIN;
+ ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, 5000), SyscallSucceedsWithValue(1));
+ pfd.fd = socket_;
+ pfd.events = POLLIN;
+ ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, 5000), SyscallSucceedsWithValue(1));
+
+ // Receive on the packet socket.
+ char recv_buf[sizeof(send_buf)];
+ ASSERT_THAT(recv(socket_, recv_buf, sizeof(recv_buf), 0),
+ SyscallSucceedsWithValue(sizeof(recv_buf)));
+ ASSERT_EQ(memcmp(recv_buf, send_buf, sizeof(send_buf)), 0);
+
+ // Receive on the UDP socket.
+ struct sockaddr_in src;
+ socklen_t src_len = sizeof(src);
+ ASSERT_THAT(recvfrom(udp_sock.get(), recv_buf, sizeof(recv_buf), MSG_DONTWAIT,
+ reinterpret_cast<struct sockaddr*>(&src), &src_len),
+ SyscallSucceedsWithValue(sizeof(kMessage)));
+ // Check src and payload.
+ EXPECT_EQ(strncmp(recv_buf, kMessage, sizeof(kMessage)), 0);
+ EXPECT_EQ(src.sin_family, AF_INET);
+ EXPECT_EQ(src.sin_port, kPort);
+ EXPECT_EQ(src.sin_addr.s_addr, htonl(INADDR_LOOPBACK));
+}
+
+INSTANTIATE_TEST_SUITE_P(AllInetTests, RawPacketTest,
+ ::testing::Values(ETH_P_IP /*, ETH_P_ALL*/));
+
+} // namespace
+
+} // namespace testing
+} // namespace gvisor
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 12:38:03 +0000