diff options
Diffstat (limited to 'test/syscalls/linux/tuntap.cc')
| -rw-r--r-- | test/syscalls/linux/tuntap.cc | 654 |
1 files changed, 0 insertions, 654 deletions
diff --git a/test/syscalls/linux/tuntap.cc b/test/syscalls/linux/tuntap.cc deleted file mode 100644 index 956208bee..000000000 --- a/test/syscalls/linux/tuntap.cc +++ /dev/null @@ -1,654 +0,0 @@ -// 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_ether.h> -#include <linux/if_tun.h> -#include <netinet/ip.h> -#include <netinet/ip_icmp.h> -#include <poll.h> -#include <sys/ioctl.h> -#include <sys/socket.h> -#include <sys/types.h> - -#include <cstddef> - -#include "gmock/gmock.h" -#include "gtest/gtest.h" -#include "absl/strings/ascii.h" -#include "absl/strings/str_split.h" -#include "test/syscalls/linux/socket_netlink_route_util.h" -#include "test/util/capability_util.h" -#include "test/util/file_descriptor.h" -#include "test/util/fs_util.h" -#include "test/util/posix_error.h" -#include "test/util/socket_util.h" -#include "test/util/test_util.h" - -namespace gvisor { -namespace testing { -namespace { - -constexpr int kIPLen = 4; - -constexpr const char kDevNetTun[] = "/dev/net/tun"; -constexpr const char kTapName[] = "tap0"; -constexpr const char kTunName[] = "tun0"; - -#define kTapIPAddr htonl(0x0a000001) /* Inet 10.0.0.1 */ -#define kTapPeerIPAddr htonl(0x0a000002) /* Inet 10.0.0.2 */ - -constexpr const uint8_t kMacA[ETH_ALEN] = {0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA}; -constexpr const uint8_t kMacB[ETH_ALEN] = {0xBB, 0xBB, 0xBB, 0xBB, 0xBB, 0xBB}; - -PosixErrorOr<std::set<std::string>> DumpLinkNames() { - ASSIGN_OR_RETURN_ERRNO(auto links, DumpLinks()); - std::set<std::string> names; - for (const auto& link : links) { - names.emplace(link.name); - } - return names; -} - -PosixErrorOr<Link> GetLinkByName(const std::string& name) { - ASSIGN_OR_RETURN_ERRNO(auto links, DumpLinks()); - for (const auto& link : links) { - if (link.name == name) { - return link; - } - } - return PosixError(ENOENT, "interface not found"); -} - -struct ping_ip_pkt { - iphdr ip; - icmphdr icmp; - char payload[64]; -} __attribute__((packed)); - -ping_ip_pkt CreatePingIPPacket(const in_addr_t srcip, const in_addr_t dstip) { - ping_ip_pkt pkt = {}; - - pkt.ip.ihl = 5; - pkt.ip.version = 4; - pkt.ip.tos = 0; - pkt.ip.tot_len = htons(sizeof(struct iphdr) + sizeof(struct icmphdr) + - sizeof(pkt.payload)); - pkt.ip.id = 1; - pkt.ip.frag_off = 1 << 6; // Do not fragment - pkt.ip.ttl = 64; - pkt.ip.protocol = IPPROTO_ICMP; - pkt.ip.daddr = dstip; - pkt.ip.saddr = srcip; - pkt.ip.check = IPChecksum(pkt.ip); - - pkt.icmp.type = ICMP_ECHO; - pkt.icmp.code = 0; - pkt.icmp.checksum = 0; - pkt.icmp.un.echo.sequence = 1; - pkt.icmp.un.echo.id = 1; - - strncpy(pkt.payload, "abcd", sizeof(pkt.payload)); - pkt.icmp.checksum = ICMPChecksum(pkt.icmp, pkt.payload, sizeof(pkt.payload)); - - return pkt; -} - -struct pihdr { - uint16_t pi_flags; - uint16_t pi_protocol; -} __attribute__((packed)); - -struct ping_pkt { - pihdr pi; - ethhdr eth; - ping_ip_pkt ip_pkt; -} __attribute__((packed)); - -ping_pkt CreatePingPacket(const uint8_t srcmac[ETH_ALEN], const in_addr_t srcip, - const uint8_t dstmac[ETH_ALEN], - const in_addr_t dstip) { - ping_pkt pkt = {}; - - pkt.pi.pi_protocol = htons(ETH_P_IP); - - memcpy(pkt.eth.h_dest, dstmac, sizeof(pkt.eth.h_dest)); - memcpy(pkt.eth.h_source, srcmac, sizeof(pkt.eth.h_source)); - pkt.eth.h_proto = htons(ETH_P_IP); - - pkt.ip_pkt = CreatePingIPPacket(srcip, dstip); - - return pkt; -} - -struct arp_pkt { - pihdr pi; - struct ethhdr eth; - struct arphdr arp; - uint8_t arp_sha[ETH_ALEN]; - uint8_t arp_spa[kIPLen]; - uint8_t arp_tha[ETH_ALEN]; - uint8_t arp_tpa[kIPLen]; -} __attribute__((packed)); - -std::string CreateArpPacket(const uint8_t srcmac[ETH_ALEN], - const in_addr_t srcip, - const uint8_t dstmac[ETH_ALEN], - const in_addr_t dstip) { - std::string buffer; - buffer.resize(sizeof(arp_pkt)); - - arp_pkt* pkt = reinterpret_cast<arp_pkt*>(&buffer[0]); - { - pkt->pi.pi_protocol = htons(ETH_P_ARP); - - memcpy(pkt->eth.h_dest, kMacA, sizeof(pkt->eth.h_dest)); - memcpy(pkt->eth.h_source, kMacB, sizeof(pkt->eth.h_source)); - pkt->eth.h_proto = htons(ETH_P_ARP); - - pkt->arp.ar_hrd = htons(ARPHRD_ETHER); - pkt->arp.ar_pro = htons(ETH_P_IP); - pkt->arp.ar_hln = ETH_ALEN; - pkt->arp.ar_pln = kIPLen; - pkt->arp.ar_op = htons(ARPOP_REPLY); - - memcpy(pkt->arp_sha, srcmac, sizeof(pkt->arp_sha)); - memcpy(pkt->arp_spa, &srcip, sizeof(pkt->arp_spa)); - memcpy(pkt->arp_tha, dstmac, sizeof(pkt->arp_tha)); - memcpy(pkt->arp_tpa, &dstip, sizeof(pkt->arp_tpa)); - } - return buffer; -} - -} // namespace - -TEST(TuntapStaticTest, NetTunExists) { - struct stat statbuf; - ASSERT_THAT(stat(kDevNetTun, &statbuf), SyscallSucceeds()); - // Check that it's a character device with rw-rw-rw- permissions. - EXPECT_EQ(statbuf.st_mode, S_IFCHR | 0666); -} - -class TuntapTest : public ::testing::Test { - protected: - void SetUp() override { - const bool have_net_admin_cap = - ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN)); - - if (have_net_admin_cap && !IsRunningOnGvisor()) { - // gVisor always creates enabled/up'd interfaces, while Linux does not (as - // observed in b/110961832). Some of the tests require the Linux stack to - // notify the socket of any link-address-resolution failures. Those - // notifications do not seem to show up when the loopback interface in the - // namespace is down. - auto link = ASSERT_NO_ERRNO_AND_VALUE(GetLinkByName("lo")); - ASSERT_NO_ERRNO(LinkChangeFlags(link.index, IFF_UP, IFF_UP)); - } - } -}; - -TEST_F(TuntapTest, CreateInterfaceNoCap) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - AutoCapability cap(CAP_NET_ADMIN, false); - - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - struct ifreq ifr = {}; - ifr.ifr_flags = IFF_TAP; - strncpy(ifr.ifr_name, kTapName, IFNAMSIZ); - - EXPECT_THAT(ioctl(fd.get(), TUNSETIFF, &ifr), SyscallFailsWithErrno(EPERM)); -} - -TEST_F(TuntapTest, CreateFixedNameInterface) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - struct ifreq ifr_set = {}; - ifr_set.ifr_flags = IFF_TAP; - strncpy(ifr_set.ifr_name, kTapName, IFNAMSIZ); - EXPECT_THAT(ioctl(fd.get(), TUNSETIFF, &ifr_set), - SyscallSucceedsWithValue(0)); - - struct ifreq ifr_get = {}; - EXPECT_THAT(ioctl(fd.get(), TUNGETIFF, &ifr_get), - SyscallSucceedsWithValue(0)); - - struct ifreq ifr_expect = ifr_set; - // See __tun_chr_ioctl() in net/drivers/tun.c. - ifr_expect.ifr_flags |= IFF_NOFILTER; - - EXPECT_THAT(DumpLinkNames(), - IsPosixErrorOkAndHolds(::testing::Contains(kTapName))); - EXPECT_THAT(memcmp(&ifr_expect, &ifr_get, sizeof(ifr_get)), ::testing::Eq(0)); -} - -TEST_F(TuntapTest, CreateInterface) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - struct ifreq ifr = {}; - ifr.ifr_flags = IFF_TAP; - // Empty ifr.ifr_name. Let kernel assign. - - EXPECT_THAT(ioctl(fd.get(), TUNSETIFF, &ifr), SyscallSucceedsWithValue(0)); - - struct ifreq ifr_get = {}; - EXPECT_THAT(ioctl(fd.get(), TUNGETIFF, &ifr_get), - SyscallSucceedsWithValue(0)); - - std::string ifname = ifr_get.ifr_name; - EXPECT_THAT(ifname, ::testing::StartsWith("tap")); - EXPECT_THAT(DumpLinkNames(), - IsPosixErrorOkAndHolds(::testing::Contains(ifname))); -} - -TEST_F(TuntapTest, InvalidReadWrite) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - char buf[128] = {}; - EXPECT_THAT(read(fd.get(), buf, sizeof(buf)), SyscallFailsWithErrno(EBADFD)); - EXPECT_THAT(write(fd.get(), buf, sizeof(buf)), SyscallFailsWithErrno(EBADFD)); -} - -TEST_F(TuntapTest, WriteToDownDevice) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - // FIXME(b/110961832): gVisor always creates enabled/up'd interfaces. - SKIP_IF(IsRunningOnGvisor()); - - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - // Device created should be down by default. - struct ifreq ifr = {}; - ifr.ifr_flags = IFF_TAP; - EXPECT_THAT(ioctl(fd.get(), TUNSETIFF, &ifr), SyscallSucceedsWithValue(0)); - - char buf[128] = {}; - EXPECT_THAT(write(fd.get(), buf, sizeof(buf)), SyscallFailsWithErrno(EIO)); -} - -struct TunTapInterface { - FileDescriptor fd; - Link link; -}; - -PosixErrorOr<TunTapInterface> OpenAndAttachTunTap(const std::string& dev_name, - const in_addr_t dev_addr, - bool tap, bool no_pi) { - // Interface creation. - ASSIGN_OR_RETURN_ERRNO(FileDescriptor fd, Open(kDevNetTun, O_RDWR)); - - struct ifreq ifr_set = {}; - if (tap) { - ifr_set.ifr_flags |= IFF_TAP; - } else { - ifr_set.ifr_flags |= IFF_TUN; - } - if (no_pi) { - ifr_set.ifr_flags |= IFF_NO_PI; - } - strncpy(ifr_set.ifr_name, dev_name.c_str(), IFNAMSIZ); - if (ioctl(fd.get(), TUNSETIFF, &ifr_set) < 0) { - return PosixError(errno); - } - - ASSIGN_OR_RETURN_ERRNO(auto link, GetLinkByName(dev_name)); - - const struct in_addr dev_ipv4_addr = {.s_addr = dev_addr}; - // Interface setup. - EXPECT_NO_ERRNO(LinkAddLocalAddr(link.index, AF_INET, /*prefixlen=*/24, - &dev_ipv4_addr, sizeof(dev_ipv4_addr))); - - if (!IsRunningOnGvisor()) { - // FIXME(b/110961832): gVisor doesn't support setting MAC address on - // interfaces yet. - if (tap) { - RETURN_IF_ERRNO(LinkSetMacAddr(link.index, kMacA, sizeof(kMacA))); - } - - // FIXME(b/110961832): gVisor always creates enabled/up'd interfaces. - RETURN_IF_ERRNO(LinkChangeFlags(link.index, IFF_UP, IFF_UP)); - } - - return TunTapInterface{.fd = std::move(fd), .link = std::move(link)}; -} - -// This test sets up a TAP device and pings kernel by sending ICMP echo request. -// -// It works as the following: -// * Open /dev/net/tun, and create kTapName interface. -// * Use rtnetlink to do initial setup of the interface: -// * Assign IP address 10.0.0.1/24 to kernel. -// * MAC address: kMacA -// * Bring up the interface. -// * Send an ICMP echo reqest (ping) packet from 10.0.0.2 (kMacB) to kernel. -// * Loop to receive packets from TAP device/fd: -// * If packet is an ICMP echo reply, it stops and passes the test. -// * If packet is an ARP request, it responds with canned reply and resends -// the -// ICMP request packet. -TEST_F(TuntapTest, PingKernel) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - const auto& [fd, link] = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTapName, kTapIPAddr, true /* tap */, false /* no_pi */)); - - ping_pkt ping_req = - CreatePingPacket(kMacB, kTapPeerIPAddr, kMacA, kTapIPAddr); - std::string arp_rep = - CreateArpPacket(kMacB, kTapPeerIPAddr, kMacA, kTapIPAddr); - - // Send ping, this would trigger an ARP request on Linux. - EXPECT_THAT(write(fd.get(), &ping_req, sizeof(ping_req)), - SyscallSucceedsWithValue(sizeof(ping_req))); - - // Receive loop to process inbound packets. - struct inpkt { - union { - pihdr pi; - ping_pkt ping; - arp_pkt arp; - }; - }; - while (1) { - inpkt r = {}; - size_t n; - EXPECT_THAT(n = read(fd.get(), &r, sizeof(r)), SyscallSucceeds()); - - if (n < sizeof(pihdr)) { - std::cerr << "Ignored packet, protocol: " << r.pi.pi_protocol - << " len: " << n << std::endl; - continue; - } - - // Process ARP packet. - if (n >= sizeof(arp_pkt) && r.pi.pi_protocol == htons(ETH_P_ARP)) { - // Respond with canned ARP reply. - EXPECT_THAT(write(fd.get(), arp_rep.data(), arp_rep.size()), - SyscallSucceedsWithValue(arp_rep.size())); - // First ping request might have been dropped due to mac address not in - // ARP cache. Send it again. - EXPECT_THAT(write(fd.get(), &ping_req, sizeof(ping_req)), - SyscallSucceedsWithValue(sizeof(ping_req))); - } - - // Process ping response packet. - if (n >= sizeof(ping_pkt) && r.pi.pi_protocol == ping_req.pi.pi_protocol && - r.ping.ip_pkt.ip.protocol == ping_req.ip_pkt.ip.protocol && - !memcmp(&r.ping.ip_pkt.ip.saddr, &ping_req.ip_pkt.ip.daddr, kIPLen) && - !memcmp(&r.ping.ip_pkt.ip.daddr, &ping_req.ip_pkt.ip.saddr, kIPLen) && - r.ping.ip_pkt.icmp.type == 0 && r.ping.ip_pkt.icmp.code == 0) { - // Ends and passes the test. - break; - } - } -} - -TEST_F(TuntapTest, SendUdpTriggersArpResolution) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - const auto& [fd, link] = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTapName, kTapIPAddr, true /* tap */, false /* no_pi */)); - - // Send a UDP packet to remote. - int sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP); - ASSERT_THAT(sock, SyscallSucceeds()); - - struct sockaddr_in remote = { - .sin_family = AF_INET, - .sin_port = htons(42), - .sin_addr = {.s_addr = kTapPeerIPAddr}, - }; - ASSERT_THAT(sendto(sock, "hello", 5, 0, AsSockAddr(&remote), sizeof(remote)), - SyscallSucceeds()); - - struct inpkt { - union { - pihdr pi; - arp_pkt arp; - }; - }; - while (1) { - inpkt r = {}; - size_t n; - EXPECT_THAT(n = read(fd.get(), &r, sizeof(r)), SyscallSucceeds()); - - if (n < sizeof(pihdr)) { - std::cerr << "Ignored packet, protocol: " << r.pi.pi_protocol - << " len: " << n << std::endl; - continue; - } - - if (n >= sizeof(arp_pkt) && r.pi.pi_protocol == htons(ETH_P_ARP)) { - break; - } - } -} - -TEST_F(TuntapTest, TUNNoPacketInfo) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - // Interface creation. - FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(kDevNetTun, O_RDWR)); - - struct ifreq ifr_set = {}; - ifr_set.ifr_flags = IFF_TUN | IFF_NO_PI; - strncpy(ifr_set.ifr_name, kTunName, IFNAMSIZ); - EXPECT_THAT(ioctl(fd.get(), TUNSETIFF, &ifr_set), SyscallSucceeds()); - - // Interface setup. - auto link = ASSERT_NO_ERRNO_AND_VALUE(GetLinkByName(kTunName)); - const struct in_addr dev_ipv4_addr = {.s_addr = kTapIPAddr}; - EXPECT_NO_ERRNO(LinkAddLocalAddr(link.index, AF_INET, 24, &dev_ipv4_addr, - sizeof(dev_ipv4_addr))); - - ping_ip_pkt ping_req = CreatePingIPPacket(kTapPeerIPAddr, kTapIPAddr); - - // Send ICMP query - EXPECT_THAT(write(fd.get(), &ping_req, sizeof(ping_req)), - SyscallSucceedsWithValue(sizeof(ping_req))); - - // Receive loop to process inbound packets. - while (1) { - ping_ip_pkt ping_resp = {}; - EXPECT_THAT(read(fd.get(), &ping_resp, sizeof(ping_req)), - SyscallSucceedsWithValue(sizeof(ping_req))); - - // Process ping response packet. - if (!memcmp(&ping_resp.ip.saddr, &ping_req.ip.daddr, kIPLen) && - !memcmp(&ping_resp.ip.daddr, &ping_req.ip.saddr, kIPLen) && - ping_resp.icmp.type == 0 && ping_resp.icmp.code == 0) { - // Ends and passes the test. - break; - } - } -} - -// TCPBlockingConnectFailsArpResolution tests for TCP connect to fail on link -// address resolution failure to a routable, but non existent peer. -TEST_F(TuntapTest, TCPBlockingConnectFailsArpResolution) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - FileDescriptor sender = - ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)); - - const auto tuntap = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTapName, kTapIPAddr, true /* tap */, false /* no_pi */)); - - sockaddr_in connect_addr = { - .sin_family = AF_INET, - .sin_addr = {.s_addr = kTapPeerIPAddr}, - }; - ASSERT_THAT(connect(sender.get(), - reinterpret_cast<const struct sockaddr*>(&connect_addr), - sizeof(connect_addr)), - SyscallFailsWithErrno(EHOSTUNREACH)); -} - -// TCPNonBlockingConnectFailsArpResolution tests for TCP non-blocking connect to -// to trigger an error event to be notified to poll on link address resolution -// failure to a routable, but non existent peer. -TEST_F(TuntapTest, TCPNonBlockingConnectFailsArpResolution) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - FileDescriptor sender = ASSERT_NO_ERRNO_AND_VALUE( - Socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP)); - - const auto tuntap = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTapName, kTapIPAddr, true /* tap */, false /* no_pi */)); - - sockaddr_in connect_addr = { - .sin_family = AF_INET, - .sin_addr = {.s_addr = kTapPeerIPAddr}, - }; - ASSERT_THAT(connect(sender.get(), - reinterpret_cast<const struct sockaddr*>(&connect_addr), - sizeof(connect_addr)), - SyscallFailsWithErrno(EINPROGRESS)); - - constexpr int kTimeout = 10000; - struct pollfd pfd = { - .fd = sender.get(), - .events = POLLIN | POLLOUT, - }; - ASSERT_THAT(poll(&pfd, 1, kTimeout), SyscallSucceedsWithValue(1)); - ASSERT_EQ(pfd.revents, POLLIN | POLLOUT | POLLHUP | POLLERR); - - ASSERT_THAT(connect(sender.get(), - reinterpret_cast<const struct sockaddr*>(&connect_addr), - sizeof(connect_addr)), - SyscallFailsWithErrno(EHOSTUNREACH)); -} - -// Write hang bug found by syskaller: b/155928773 -// https://syzkaller.appspot.com/bug?id=065b893bd8d1d04a4e0a1d53c578537cde1efe99 -TEST_F(TuntapTest, WriteHangBug155928773) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - - const auto tuntap = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTapName, kTapIPAddr, true /* tap */, false /* no_pi */)); - - int sock = socket(AF_INET, SOCK_DGRAM, 0); - ASSERT_THAT(sock, SyscallSucceeds()); - - struct sockaddr_in remote = { - .sin_family = AF_INET, - .sin_port = htons(42), - .sin_addr = {.s_addr = kTapIPAddr}, - }; - // Return values do not matter in this test. - connect(sock, AsSockAddr(&remote), sizeof(remote)); - write(sock, "hello", 5); -} - -// Test that raw packet sockets do not need/include link headers when -// sending/receiving packets to/from pure L3 (e.g. TUN) interfaces. -TEST_F(TuntapTest, RawPacketSocket) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_ADMIN))); - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_NET_RAW))); - - auto [tun, link] = ASSERT_NO_ERRNO_AND_VALUE(OpenAndAttachTunTap( - kTunName, kTapIPAddr, false /* tap */, true /* no_pi */)); - FileDescriptor packet_sock = - ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_PACKET, SOCK_RAW, htons(ETH_P_IP))); - - constexpr int kInfiniteTimeout = -1; - - uint8_t hardware_address_length = 0; - if (IsRunningOnGvisor()) { - // TODO(https://gvisor.dev/issue/6530): Do not assume all interfaces have - // an ethernet address. - hardware_address_length = ETH_ALEN; - } - - { - const ping_ip_pkt ping_req = CreatePingIPPacket(kTapPeerIPAddr, kTapIPAddr); - ASSERT_THAT(write(tun.get(), &ping_req, sizeof(ping_req)), - SyscallSucceedsWithValue(sizeof(ping_req))); - // Wait for the packet socket to become readable. - pollfd pfd = { - .fd = packet_sock.get(), - .events = POLLIN, - }; - ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, kInfiniteTimeout), - SyscallSucceedsWithValue(1)); - - char read_buf[sizeof(ping_req) + 1]; - struct sockaddr_ll src; - socklen_t src_len = sizeof(src); - ASSERT_THAT(recvfrom(packet_sock.get(), read_buf, sizeof(read_buf), 0, - reinterpret_cast<struct sockaddr*>(&src), &src_len), - SyscallSucceedsWithValue(sizeof(ping_req))); - EXPECT_EQ(memcmp(read_buf, &ping_req, sizeof(ping_req)), 0); - ASSERT_EQ(src_len, sizeof(src)); - EXPECT_EQ(src.sll_family, AF_PACKET); - EXPECT_EQ(ntohs(src.sll_protocol), ETH_P_IP); - EXPECT_EQ(src.sll_ifindex, link.index); - EXPECT_EQ(src.sll_pkttype, PACKET_HOST); - EXPECT_EQ(src.sll_halen, hardware_address_length); - if (IsRunningOnGvisor()) { - // TODO(https://gvisor.dev/issue/6531): Check this field for the right - // hardware type. - EXPECT_EQ(src.sll_hatype, 0); - } else { - EXPECT_EQ(src.sll_hatype, ARPHRD_NONE); - } - } - - { - const struct sockaddr_ll dest = { - .sll_family = AF_PACKET, - .sll_protocol = htons(ETH_P_IP), - .sll_ifindex = link.index, - .sll_halen = hardware_address_length, - }; - - const ping_ip_pkt ping_req = CreatePingIPPacket(kTapIPAddr, kTapPeerIPAddr); - ASSERT_THAT( - sendto(packet_sock.get(), &ping_req, sizeof(ping_req), 0, - reinterpret_cast<const struct sockaddr*>(&dest), sizeof(dest)), - SyscallSucceedsWithValue(sizeof(ping_req))); - - // Loop until we receive the packet we expect - the kernel may send packets - // we do not care about. - while (true) { - // Wait for the TUN interface to become readable. - pollfd pfd = { - .fd = tun.get(), - .events = POLLIN, - }; - ASSERT_THAT(RetryEINTR(poll)(&pfd, 1, kInfiniteTimeout), - SyscallSucceedsWithValue(1)); - - char read_buf[sizeof(ping_req) + 1]; - int n = read(tun.get(), &read_buf, sizeof(read_buf)); - ASSERT_THAT(n, SyscallSucceeds()); - if (n == sizeof(ping_req) && - memcmp(read_buf, &ping_req, sizeof(ping_req)) == 0) { - break; - } - } - } -} - -} // namespace testing -} // namespace gvisor |