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Diffstat (limited to 'test/syscalls/linux/pty.cc')
| -rw-r--r-- | test/syscalls/linux/pty.cc | 1735 |
1 files changed, 0 insertions, 1735 deletions
diff --git a/test/syscalls/linux/pty.cc b/test/syscalls/linux/pty.cc deleted file mode 100644 index e6b12f81c..000000000 --- a/test/syscalls/linux/pty.cc +++ /dev/null @@ -1,1735 +0,0 @@ -// Copyright 2018 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 <fcntl.h> -#include <linux/capability.h> -#include <linux/major.h> -#include <poll.h> -#include <sched.h> -#include <signal.h> -#include <sys/ioctl.h> -#include <sys/mman.h> -#include <sys/stat.h> -#include <sys/sysmacros.h> -#include <sys/types.h> -#include <sys/wait.h> -#include <termios.h> -#include <unistd.h> - -#include <iostream> - -#include "gtest/gtest.h" -#include "absl/base/macros.h" -#include "absl/strings/str_cat.h" -#include "absl/synchronization/notification.h" -#include "absl/time/clock.h" -#include "absl/time/time.h" -#include "test/util/capability_util.h" -#include "test/util/cleanup.h" -#include "test/util/file_descriptor.h" -#include "test/util/posix_error.h" -#include "test/util/pty_util.h" -#include "test/util/test_util.h" -#include "test/util/thread_util.h" - -namespace gvisor { -namespace testing { - -namespace { - -using ::testing::AnyOf; -using ::testing::Contains; -using ::testing::Eq; -using ::testing::Not; -using SubprocessCallback = std::function<void()>; - -// Tests Unix98 pseudoterminals. -// -// These tests assume that /dev/ptmx exists and is associated with a devpts -// filesystem mounted at /dev/pts/. While a Linux distribution could -// theoretically place those anywhere, glibc expects those locations, so they -// are effectively fixed. - -// Minor device number for an unopened ptmx file. -constexpr int kPtmxMinor = 2; - -// The timeout when polling for data from a pty. When data is written to one end -// of a pty, Linux asynchronously makes it available to the other end, so we -// have to wait. -constexpr absl::Duration kTimeout = absl::Seconds(20); - -// The maximum line size in bytes returned per read from a pty file. -constexpr int kMaxLineSize = 4096; - -constexpr char kMasterPath[] = "/dev/ptmx"; - -// glibc defines its own, different, version of struct termios. We care about -// what the kernel does, not glibc. -#define KERNEL_NCCS 19 -struct kernel_termios { - tcflag_t c_iflag; - tcflag_t c_oflag; - tcflag_t c_cflag; - tcflag_t c_lflag; - cc_t c_line; - cc_t c_cc[KERNEL_NCCS]; -}; - -bool operator==(struct kernel_termios const& a, - struct kernel_termios const& b) { - return memcmp(&a, &b, sizeof(a)) == 0; -} - -// Returns the termios-style control character for the passed character. -// -// e.g., for Ctrl-C, i.e., ^C, call ControlCharacter('C'). -// -// Standard control characters are ASCII bytes 0 through 31. -constexpr char ControlCharacter(char c) { - // A is 1, B is 2, etc. - return c - 'A' + 1; -} - -// Returns the printable character the given control character represents. -constexpr char FromControlCharacter(char c) { return c + 'A' - 1; } - -// Returns true if c is a control character. -// -// Standard control characters are ASCII bytes 0 through 31. -constexpr bool IsControlCharacter(char c) { return c <= 31; } - -struct Field { - const char* name; - uint64_t mask; - uint64_t value; -}; - -// ParseFields returns a string representation of value, using the names in -// fields. -std::string ParseFields(const Field* fields, size_t len, uint64_t value) { - bool first = true; - std::string s; - for (size_t i = 0; i < len; i++) { - const Field f = fields[i]; - if ((value & f.mask) == f.value) { - if (!first) { - s += "|"; - } - s += f.name; - first = false; - value &= ~f.mask; - } - } - - if (value) { - if (!first) { - s += "|"; - } - absl::StrAppend(&s, value); - } - - return s; -} - -const Field kIflagFields[] = { - {"IGNBRK", IGNBRK, IGNBRK}, {"BRKINT", BRKINT, BRKINT}, - {"IGNPAR", IGNPAR, IGNPAR}, {"PARMRK", PARMRK, PARMRK}, - {"INPCK", INPCK, INPCK}, {"ISTRIP", ISTRIP, ISTRIP}, - {"INLCR", INLCR, INLCR}, {"IGNCR", IGNCR, IGNCR}, - {"ICRNL", ICRNL, ICRNL}, {"IUCLC", IUCLC, IUCLC}, - {"IXON", IXON, IXON}, {"IXANY", IXANY, IXANY}, - {"IXOFF", IXOFF, IXOFF}, {"IMAXBEL", IMAXBEL, IMAXBEL}, - {"IUTF8", IUTF8, IUTF8}, -}; - -const Field kOflagFields[] = { - {"OPOST", OPOST, OPOST}, {"OLCUC", OLCUC, OLCUC}, - {"ONLCR", ONLCR, ONLCR}, {"OCRNL", OCRNL, OCRNL}, - {"ONOCR", ONOCR, ONOCR}, {"ONLRET", ONLRET, ONLRET}, - {"OFILL", OFILL, OFILL}, {"OFDEL", OFDEL, OFDEL}, - {"NL0", NLDLY, NL0}, {"NL1", NLDLY, NL1}, - {"CR0", CRDLY, CR0}, {"CR1", CRDLY, CR1}, - {"CR2", CRDLY, CR2}, {"CR3", CRDLY, CR3}, - {"TAB0", TABDLY, TAB0}, {"TAB1", TABDLY, TAB1}, - {"TAB2", TABDLY, TAB2}, {"TAB3", TABDLY, TAB3}, - {"BS0", BSDLY, BS0}, {"BS1", BSDLY, BS1}, - {"FF0", FFDLY, FF0}, {"FF1", FFDLY, FF1}, - {"VT0", VTDLY, VT0}, {"VT1", VTDLY, VT1}, - {"XTABS", XTABS, XTABS}, -}; - -#ifndef IBSHIFT -// Shift from CBAUD to CIBAUD. -#define IBSHIFT 16 -#endif - -const Field kCflagFields[] = { - {"B0", CBAUD, B0}, - {"B50", CBAUD, B50}, - {"B75", CBAUD, B75}, - {"B110", CBAUD, B110}, - {"B134", CBAUD, B134}, - {"B150", CBAUD, B150}, - {"B200", CBAUD, B200}, - {"B300", CBAUD, B300}, - {"B600", CBAUD, B600}, - {"B1200", CBAUD, B1200}, - {"B1800", CBAUD, B1800}, - {"B2400", CBAUD, B2400}, - {"B4800", CBAUD, B4800}, - {"B9600", CBAUD, B9600}, - {"B19200", CBAUD, B19200}, - {"B38400", CBAUD, B38400}, - {"CS5", CSIZE, CS5}, - {"CS6", CSIZE, CS6}, - {"CS7", CSIZE, CS7}, - {"CS8", CSIZE, CS8}, - {"CSTOPB", CSTOPB, CSTOPB}, - {"CREAD", CREAD, CREAD}, - {"PARENB", PARENB, PARENB}, - {"PARODD", PARODD, PARODD}, - {"HUPCL", HUPCL, HUPCL}, - {"CLOCAL", CLOCAL, CLOCAL}, - {"B57600", CBAUD, B57600}, - {"B115200", CBAUD, B115200}, - {"B230400", CBAUD, B230400}, - {"B460800", CBAUD, B460800}, - {"B500000", CBAUD, B500000}, - {"B576000", CBAUD, B576000}, - {"B921600", CBAUD, B921600}, - {"B1000000", CBAUD, B1000000}, - {"B1152000", CBAUD, B1152000}, - {"B1500000", CBAUD, B1500000}, - {"B2000000", CBAUD, B2000000}, - {"B2500000", CBAUD, B2500000}, - {"B3000000", CBAUD, B3000000}, - {"B3500000", CBAUD, B3500000}, - {"B4000000", CBAUD, B4000000}, - {"CMSPAR", CMSPAR, CMSPAR}, - {"CRTSCTS", CRTSCTS, CRTSCTS}, - {"IB0", CIBAUD, B0 << IBSHIFT}, - {"IB50", CIBAUD, B50 << IBSHIFT}, - {"IB75", CIBAUD, B75 << IBSHIFT}, - {"IB110", CIBAUD, B110 << IBSHIFT}, - {"IB134", CIBAUD, B134 << IBSHIFT}, - {"IB150", CIBAUD, B150 << IBSHIFT}, - {"IB200", CIBAUD, B200 << IBSHIFT}, - {"IB300", CIBAUD, B300 << IBSHIFT}, - {"IB600", CIBAUD, B600 << IBSHIFT}, - {"IB1200", CIBAUD, B1200 << IBSHIFT}, - {"IB1800", CIBAUD, B1800 << IBSHIFT}, - {"IB2400", CIBAUD, B2400 << IBSHIFT}, - {"IB4800", CIBAUD, B4800 << IBSHIFT}, - {"IB9600", CIBAUD, B9600 << IBSHIFT}, - {"IB19200", CIBAUD, B19200 << IBSHIFT}, - {"IB38400", CIBAUD, B38400 << IBSHIFT}, - {"IB57600", CIBAUD, B57600 << IBSHIFT}, - {"IB115200", CIBAUD, B115200 << IBSHIFT}, - {"IB230400", CIBAUD, B230400 << IBSHIFT}, - {"IB460800", CIBAUD, B460800 << IBSHIFT}, - {"IB500000", CIBAUD, B500000 << IBSHIFT}, - {"IB576000", CIBAUD, B576000 << IBSHIFT}, - {"IB921600", CIBAUD, B921600 << IBSHIFT}, - {"IB1000000", CIBAUD, B1000000 << IBSHIFT}, - {"IB1152000", CIBAUD, B1152000 << IBSHIFT}, - {"IB1500000", CIBAUD, B1500000 << IBSHIFT}, - {"IB2000000", CIBAUD, B2000000 << IBSHIFT}, - {"IB2500000", CIBAUD, B2500000 << IBSHIFT}, - {"IB3000000", CIBAUD, B3000000 << IBSHIFT}, - {"IB3500000", CIBAUD, B3500000 << IBSHIFT}, - {"IB4000000", CIBAUD, B4000000 << IBSHIFT}, -}; - -const Field kLflagFields[] = { - {"ISIG", ISIG, ISIG}, {"ICANON", ICANON, ICANON}, - {"XCASE", XCASE, XCASE}, {"ECHO", ECHO, ECHO}, - {"ECHOE", ECHOE, ECHOE}, {"ECHOK", ECHOK, ECHOK}, - {"ECHONL", ECHONL, ECHONL}, {"NOFLSH", NOFLSH, NOFLSH}, - {"TOSTOP", TOSTOP, TOSTOP}, {"ECHOCTL", ECHOCTL, ECHOCTL}, - {"ECHOPRT", ECHOPRT, ECHOPRT}, {"ECHOKE", ECHOKE, ECHOKE}, - {"FLUSHO", FLUSHO, FLUSHO}, {"PENDIN", PENDIN, PENDIN}, - {"IEXTEN", IEXTEN, IEXTEN}, {"EXTPROC", EXTPROC, EXTPROC}, -}; - -std::string FormatCC(char c) { - if (isgraph(c)) { - return std::string(1, c); - } else if (c == ' ') { - return " "; - } else if (c == '\t') { - return "\\t"; - } else if (c == '\r') { - return "\\r"; - } else if (c == '\n') { - return "\\n"; - } else if (c == '\0') { - return "\\0"; - } else if (IsControlCharacter(c)) { - return absl::StrCat("^", std::string(1, FromControlCharacter(c))); - } - return absl::StrCat("\\x", absl::Hex(c)); -} - -std::ostream& operator<<(std::ostream& os, struct kernel_termios const& a) { - os << "{ c_iflag = " - << ParseFields(kIflagFields, ABSL_ARRAYSIZE(kIflagFields), a.c_iflag); - os << ", c_oflag = " - << ParseFields(kOflagFields, ABSL_ARRAYSIZE(kOflagFields), a.c_oflag); - os << ", c_cflag = " - << ParseFields(kCflagFields, ABSL_ARRAYSIZE(kCflagFields), a.c_cflag); - os << ", c_lflag = " - << ParseFields(kLflagFields, ABSL_ARRAYSIZE(kLflagFields), a.c_lflag); - os << ", c_line = " << a.c_line; - os << ", c_cc = { [VINTR] = '" << FormatCC(a.c_cc[VINTR]); - os << "', [VQUIT] = '" << FormatCC(a.c_cc[VQUIT]); - os << "', [VERASE] = '" << FormatCC(a.c_cc[VERASE]); - os << "', [VKILL] = '" << FormatCC(a.c_cc[VKILL]); - os << "', [VEOF] = '" << FormatCC(a.c_cc[VEOF]); - os << "', [VTIME] = '" << static_cast<int>(a.c_cc[VTIME]); - os << "', [VMIN] = " << static_cast<int>(a.c_cc[VMIN]); - os << ", [VSWTC] = '" << FormatCC(a.c_cc[VSWTC]); - os << "', [VSTART] = '" << FormatCC(a.c_cc[VSTART]); - os << "', [VSTOP] = '" << FormatCC(a.c_cc[VSTOP]); - os << "', [VSUSP] = '" << FormatCC(a.c_cc[VSUSP]); - os << "', [VEOL] = '" << FormatCC(a.c_cc[VEOL]); - os << "', [VREPRINT] = '" << FormatCC(a.c_cc[VREPRINT]); - os << "', [VDISCARD] = '" << FormatCC(a.c_cc[VDISCARD]); - os << "', [VWERASE] = '" << FormatCC(a.c_cc[VWERASE]); - os << "', [VLNEXT] = '" << FormatCC(a.c_cc[VLNEXT]); - os << "', [VEOL2] = '" << FormatCC(a.c_cc[VEOL2]); - os << "'}"; - return os; -} - -// Return the default termios settings for a new terminal. -struct kernel_termios DefaultTermios() { - struct kernel_termios t = {}; - t.c_iflag = IXON | ICRNL; - t.c_oflag = OPOST | ONLCR; - t.c_cflag = B38400 | CSIZE | CS8 | CREAD; - t.c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN; - t.c_line = 0; - t.c_cc[VINTR] = ControlCharacter('C'); - t.c_cc[VQUIT] = ControlCharacter('\\'); - t.c_cc[VERASE] = '\x7f'; - t.c_cc[VKILL] = ControlCharacter('U'); - t.c_cc[VEOF] = ControlCharacter('D'); - t.c_cc[VTIME] = '\0'; - t.c_cc[VMIN] = 1; - t.c_cc[VSWTC] = '\0'; - t.c_cc[VSTART] = ControlCharacter('Q'); - t.c_cc[VSTOP] = ControlCharacter('S'); - t.c_cc[VSUSP] = ControlCharacter('Z'); - t.c_cc[VEOL] = '\0'; - t.c_cc[VREPRINT] = ControlCharacter('R'); - t.c_cc[VDISCARD] = ControlCharacter('O'); - t.c_cc[VWERASE] = ControlCharacter('W'); - t.c_cc[VLNEXT] = ControlCharacter('V'); - t.c_cc[VEOL2] = '\0'; - return t; -} - -// PollAndReadFd tries to read count bytes from buf within timeout. -// -// Returns a partial read if some bytes were read. -// -// fd must be non-blocking. -PosixErrorOr<size_t> PollAndReadFd(int fd, void* buf, size_t count, - absl::Duration timeout) { - absl::Time end = absl::Now() + timeout; - - size_t completed = 0; - absl::Duration remaining; - while ((remaining = end - absl::Now()) > absl::ZeroDuration()) { - struct pollfd pfd = {fd, POLLIN, 0}; - int ret = RetryEINTR(poll)(&pfd, 1, absl::ToInt64Milliseconds(remaining)); - if (ret < 0) { - return PosixError(errno, "poll failed"); - } else if (ret == 0) { - // Timed out. - continue; - } else if (ret != 1) { - return PosixError(EINVAL, absl::StrCat("Bad poll ret ", ret)); - } - - ssize_t n = - ReadFd(fd, static_cast<char*>(buf) + completed, count - completed); - if (n < 0) { - if (errno == EAGAIN) { - // Linux sometimes returns EAGAIN from this read, despite the fact that - // poll returned success. Let's just do what do as we are told and try - // again. - continue; - } - return PosixError(errno, "read failed"); - } - completed += n; - if (completed >= count) { - return completed; - } - } - - if (completed) { - return completed; - } - return PosixError(ETIMEDOUT, "Poll timed out"); -} - -TEST(PtyTrunc, Truncate) { - // Opening PTYs with O_TRUNC shouldn't cause an error, but calls to - // (f)truncate should. - FileDescriptor master = - ASSERT_NO_ERRNO_AND_VALUE(Open(kMasterPath, O_RDWR | O_TRUNC)); - int n = ASSERT_NO_ERRNO_AND_VALUE(ReplicaID(master)); - std::string spath = absl::StrCat("/dev/pts/", n); - FileDescriptor replica = - ASSERT_NO_ERRNO_AND_VALUE(Open(spath, O_RDWR | O_NONBLOCK | O_TRUNC)); - - EXPECT_THAT(truncate(kMasterPath, 0), SyscallFailsWithErrno(EINVAL)); - EXPECT_THAT(truncate(spath.c_str(), 0), SyscallFailsWithErrno(EINVAL)); - EXPECT_THAT(ftruncate(master.get(), 0), SyscallFailsWithErrno(EINVAL)); - EXPECT_THAT(ftruncate(replica.get(), 0), SyscallFailsWithErrno(EINVAL)); -} - -TEST(BasicPtyTest, StatUnopenedMaster) { - struct stat s; - ASSERT_THAT(stat(kMasterPath, &s), SyscallSucceeds()); - - EXPECT_EQ(s.st_rdev, makedev(TTYAUX_MAJOR, kPtmxMinor)); - EXPECT_EQ(s.st_size, 0); - EXPECT_EQ(s.st_blocks, 0); - - // ptmx attached to a specific devpts mount uses block size 1024. See - // fs/devpts/inode.c:devpts_fill_super. - // - // The global ptmx device uses the block size of the filesystem it is created - // on (which is usually 4096 for disk filesystems). - EXPECT_THAT(s.st_blksize, AnyOf(Eq(1024), Eq(4096))); -} - -// Waits for count bytes to be readable from fd. Unlike poll, which can return -// before all data is moved into a pty's read buffer, this function waits for -// all count bytes to become readable. -PosixErrorOr<int> WaitUntilReceived(int fd, int count) { - int buffered = -1; - absl::Duration remaining; - absl::Time end = absl::Now() + kTimeout; - while ((remaining = end - absl::Now()) > absl::ZeroDuration()) { - if (ioctl(fd, FIONREAD, &buffered) < 0) { - return PosixError(errno, "failed FIONREAD ioctl"); - } - if (buffered >= count) { - return buffered; - } - absl::SleepFor(absl::Milliseconds(500)); - } - return PosixError( - ETIMEDOUT, - absl::StrFormat( - "FIONREAD timed out, receiving only %d of %d expected bytes", - buffered, count)); -} - -// Verifies that there is nothing left to read from fd. -void ExpectFinished(const FileDescriptor& fd) { - // Nothing more to read. - char c; - EXPECT_THAT(ReadFd(fd.get(), &c, 1), SyscallFailsWithErrno(EAGAIN)); -} - -// Verifies that we can read expected bytes from fd into buf. -void ExpectReadable(const FileDescriptor& fd, int expected, char* buf) { - size_t n = ASSERT_NO_ERRNO_AND_VALUE( - PollAndReadFd(fd.get(), buf, expected, kTimeout)); - EXPECT_EQ(expected, n); -} - -TEST(BasicPtyTest, OpenMasterReplica) { - FileDescriptor master = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - FileDescriptor replica = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master)); -} - -TEST(BasicPtyTest, OpenSetsControllingTTY) { - SKIP_IF(IsRunningWithVFS1()); - // setsid either puts us in a new session or fails because we're already the - // session leader. Either way, this ensures we're the session leader. - setsid(); - - // Make sure we're ignoring SIGHUP, which will be sent to this process once we - // disconnect they TTY. - struct sigaction sa = {}; - sa.sa_handler = SIG_IGN; - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - struct sigaction old_sa; - ASSERT_THAT(sigaction(SIGHUP, &sa, &old_sa), SyscallSucceeds()); - auto cleanup = Cleanup([old_sa] { - EXPECT_THAT(sigaction(SIGHUP, &old_sa, NULL), SyscallSucceeds()); - }); - - FileDescriptor master = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - FileDescriptor replica = - ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master, O_NONBLOCK | O_RDWR)); - - // Opening replica should make it our controlling TTY, and therefore we are - // able to give it up. - ASSERT_THAT(ioctl(replica.get(), TIOCNOTTY), SyscallSucceeds()); -} - -TEST(BasicPtyTest, OpenMasterDoesNotSetsControllingTTY) { - SKIP_IF(IsRunningWithVFS1()); - // setsid either puts us in a new session or fails because we're already the - // session leader. Either way, this ensures we're the session leader. - setsid(); - FileDescriptor master = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - - // Opening master does not set the controlling TTY, and therefore we are - // unable to give it up. - ASSERT_THAT(ioctl(master.get(), TIOCNOTTY), SyscallFailsWithErrno(ENOTTY)); -} - -TEST(BasicPtyTest, OpenNOCTTY) { - SKIP_IF(IsRunningWithVFS1()); - // setsid either puts us in a new session or fails because we're already the - // session leader. Either way, this ensures we're the session leader. - setsid(); - FileDescriptor master = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - FileDescriptor replica = ASSERT_NO_ERRNO_AND_VALUE( - OpenReplica(master, O_NOCTTY | O_NONBLOCK | O_RDWR)); - - // Opening replica with O_NOCTTY won't make it our controlling TTY, and - // therefore we are unable to give it up. - ASSERT_THAT(ioctl(replica.get(), TIOCNOTTY), SyscallFailsWithErrno(ENOTTY)); -} - -// The replica entry in /dev/pts/ disappears when the master is closed, even if -// the replica is still open. -TEST(BasicPtyTest, ReplicaEntryGoneAfterMasterClose) { - FileDescriptor master = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - FileDescriptor replica = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master)); - - // Get pty index. - int index = -1; - ASSERT_THAT(ioctl(master.get(), TIOCGPTN, &index), SyscallSucceeds()); - - std::string path = absl::StrCat("/dev/pts/", index); - - struct stat st; - EXPECT_THAT(stat(path.c_str(), &st), SyscallSucceeds()); - - master.reset(); - - EXPECT_THAT(stat(path.c_str(), &st), SyscallFailsWithErrno(ENOENT)); -} - -TEST(BasicPtyTest, Getdents) { - FileDescriptor master1 = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - int index1 = -1; - ASSERT_THAT(ioctl(master1.get(), TIOCGPTN, &index1), SyscallSucceeds()); - FileDescriptor replica1 = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master1)); - - FileDescriptor master2 = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR)); - int index2 = -1; - ASSERT_THAT(ioctl(master2.get(), TIOCGPTN, &index2), SyscallSucceeds()); - FileDescriptor replica2 = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master2)); - - // The directory contains ptmx, index1, and index2. (Plus any additional PTYs - // unrelated to this test.) - - std::vector<std::string> contents = - ASSERT_NO_ERRNO_AND_VALUE(ListDir("/dev/pts/", true)); - EXPECT_THAT(contents, Contains(absl::StrCat(index1))); - EXPECT_THAT(contents, Contains(absl::StrCat(index2))); - - master2.reset(); - - // The directory contains ptmx and index1, but not index2 since the master is - // closed. (Plus any additional PTYs unrelated to this test.) - - contents = ASSERT_NO_ERRNO_AND_VALUE(ListDir("/dev/pts/", true)); - EXPECT_THAT(contents, Contains(absl::StrCat(index1))); - EXPECT_THAT(contents, Not(Contains(absl::StrCat(index2)))); - - // N.B. devpts supports legacy "single-instance" mode and new "multi-instance" - // mode. In legacy mode, devpts does not contain a "ptmx" device (the distro - // must use mknod to create it somewhere, presumably /dev/ptmx). - // Multi-instance mode does include a "ptmx" device tied to that mount. - // - // We don't check for the presence or absence of "ptmx", as distros vary in - // their usage of the two modes. -} - -class PtyTest : public ::testing::Test { - protected: - void SetUp() override { - master_ = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR | O_NONBLOCK)); - replica_ = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master_)); - } - - void DisableCanonical() { - struct kernel_termios t = {}; - EXPECT_THAT(ioctl(replica_.get(), TCGETS, &t), SyscallSucceeds()); - t.c_lflag &= ~ICANON; - EXPECT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - } - - void EnableCanonical() { - struct kernel_termios t = {}; - EXPECT_THAT(ioctl(replica_.get(), TCGETS, &t), SyscallSucceeds()); - t.c_lflag |= ICANON; - EXPECT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - } - - // Master and replica ends of the PTY. Non-blocking. - FileDescriptor master_; - FileDescriptor replica_; -}; - -// Master to replica sanity test. -TEST_F(PtyTest, WriteMasterToReplica) { - // N.B. by default, the replica reads nothing until the master writes a - // newline. - constexpr char kBuf[] = "hello\n"; - - EXPECT_THAT(WriteFd(master_.get(), kBuf, sizeof(kBuf) - 1), - SyscallSucceedsWithValue(sizeof(kBuf) - 1)); - - // Linux moves data from the master to the replica via async work scheduled - // via tty_flip_buffer_push. Since it is asynchronous, the data may not be - // available for reading immediately. Instead we must poll and assert that it - // becomes available "soon". - - char buf[sizeof(kBuf)] = {}; - ExpectReadable(replica_, sizeof(buf) - 1, buf); - - EXPECT_EQ(memcmp(buf, kBuf, sizeof(kBuf)), 0); -} - -// Replica to master sanity test. -TEST_F(PtyTest, WriteReplicaToMaster) { - // N.B. by default, the master reads nothing until the replica writes a - // newline, and the master gets a carriage return. - constexpr char kInput[] = "hello\n"; - constexpr char kExpected[] = "hello\r\n"; - - EXPECT_THAT(WriteFd(replica_.get(), kInput, sizeof(kInput) - 1), - SyscallSucceedsWithValue(sizeof(kInput) - 1)); - - // Linux moves data from the master to the replica via async work scheduled - // via tty_flip_buffer_push. Since it is asynchronous, the data may not be - // available for reading immediately. Instead we must poll and assert that it - // becomes available "soon". - - char buf[sizeof(kExpected)] = {}; - ExpectReadable(master_, sizeof(buf) - 1, buf); - - EXPECT_EQ(memcmp(buf, kExpected, sizeof(kExpected)), 0); -} - -TEST_F(PtyTest, WriteInvalidUTF8) { - char c = 0xff; - ASSERT_THAT(syscall(__NR_write, master_.get(), &c, sizeof(c)), - SyscallSucceedsWithValue(sizeof(c))); -} - -// Both the master and replica report the standard default termios settings. -// -// Note that TCGETS on the master actually redirects to the replica (see comment -// on MasterTermiosUnchangable). -TEST_F(PtyTest, DefaultTermios) { - struct kernel_termios t = {}; - EXPECT_THAT(ioctl(replica_.get(), TCGETS, &t), SyscallSucceeds()); - EXPECT_EQ(t, DefaultTermios()); - - EXPECT_THAT(ioctl(master_.get(), TCGETS, &t), SyscallSucceeds()); - EXPECT_EQ(t, DefaultTermios()); -} - -// Changing termios from the master actually affects the replica. -// -// TCSETS on the master actually redirects to the replica (see comment on -// MasterTermiosUnchangable). -TEST_F(PtyTest, TermiosAffectsReplica) { - struct kernel_termios master_termios = {}; - EXPECT_THAT(ioctl(master_.get(), TCGETS, &master_termios), SyscallSucceeds()); - master_termios.c_lflag ^= ICANON; - EXPECT_THAT(ioctl(master_.get(), TCSETS, &master_termios), SyscallSucceeds()); - - struct kernel_termios replica_termios = {}; - EXPECT_THAT(ioctl(replica_.get(), TCGETS, &replica_termios), - SyscallSucceeds()); - EXPECT_EQ(master_termios, replica_termios); -} - -// The master end of the pty has termios: -// -// struct kernel_termios t = { -// .c_iflag = 0; -// .c_oflag = 0; -// .c_cflag = B38400 | CS8 | CREAD; -// .c_lflag = 0; -// .c_cc = /* same as DefaultTermios */ -// } -// -// (From drivers/tty/pty.c:unix98_pty_init) -// -// All termios control ioctls on the master actually redirect to the replica -// (drivers/tty/tty_ioctl.c:tty_mode_ioctl), making it impossible to change the -// master termios. -// -// Verify this by setting ICRNL (which rewrites input \r to \n) and verify that -// it has no effect on the master. -TEST_F(PtyTest, MasterTermiosUnchangable) { - struct kernel_termios master_termios = {}; - EXPECT_THAT(ioctl(master_.get(), TCGETS, &master_termios), SyscallSucceeds()); - master_termios.c_lflag |= ICRNL; - EXPECT_THAT(ioctl(master_.get(), TCSETS, &master_termios), SyscallSucceeds()); - - char c = '\r'; - ASSERT_THAT(WriteFd(replica_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - ExpectReadable(master_, 1, &c); - EXPECT_EQ(c, '\r'); // ICRNL had no effect! - - ExpectFinished(master_); -} - -// ICRNL rewrites input \r to \n. -TEST_F(PtyTest, TermiosICRNL) { - struct kernel_termios t = DefaultTermios(); - t.c_iflag |= ICRNL; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - char c = '\r'; - ASSERT_THAT(WriteFd(master_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - ExpectReadable(replica_, 1, &c); - EXPECT_EQ(c, '\n'); - - ExpectFinished(replica_); -} - -// ONLCR rewrites output \n to \r\n. -TEST_F(PtyTest, TermiosONLCR) { - struct kernel_termios t = DefaultTermios(); - t.c_oflag |= ONLCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - char c = '\n'; - ASSERT_THAT(WriteFd(replica_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - // Extra byte for NUL for EXPECT_STREQ. - char buf[3] = {}; - ExpectReadable(master_, 2, buf); - EXPECT_STREQ(buf, "\r\n"); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, TermiosIGNCR) { - struct kernel_termios t = DefaultTermios(); - t.c_iflag |= IGNCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - char c = '\r'; - ASSERT_THAT(WriteFd(master_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - // Nothing to read. - ASSERT_THAT(PollAndReadFd(replica_.get(), &c, 1, kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); -} - -// Test that we can successfully poll for readable data from the replica. -TEST_F(PtyTest, TermiosPollReplica) { - struct kernel_termios t = DefaultTermios(); - t.c_iflag |= IGNCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - absl::Notification notify; - int sfd = replica_.get(); - ScopedThread th([sfd, ¬ify]() { - notify.Notify(); - - // Poll on the reader fd with POLLIN event. - struct pollfd poll_fd = {sfd, POLLIN, 0}; - EXPECT_THAT( - RetryEINTR(poll)(&poll_fd, 1, absl::ToInt64Milliseconds(kTimeout)), - SyscallSucceedsWithValue(1)); - - // Should trigger POLLIN event. - EXPECT_EQ(poll_fd.revents & POLLIN, POLLIN); - }); - - notify.WaitForNotification(); - // Sleep ensures that poll begins waiting before we write to the FD. - absl::SleepFor(absl::Seconds(1)); - - char s[] = "foo\n"; - ASSERT_THAT(WriteFd(master_.get(), s, strlen(s) + 1), SyscallSucceeds()); -} - -// Test that we can successfully poll for readable data from the master. -TEST_F(PtyTest, TermiosPollMaster) { - struct kernel_termios t = DefaultTermios(); - t.c_iflag |= IGNCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(master_.get(), TCSETS, &t), SyscallSucceeds()); - - absl::Notification notify; - int mfd = master_.get(); - ScopedThread th([mfd, ¬ify]() { - notify.Notify(); - - // Poll on the reader fd with POLLIN event. - struct pollfd poll_fd = {mfd, POLLIN, 0}; - EXPECT_THAT( - RetryEINTR(poll)(&poll_fd, 1, absl::ToInt64Milliseconds(kTimeout)), - SyscallSucceedsWithValue(1)); - - // Should trigger POLLIN event. - EXPECT_EQ(poll_fd.revents & POLLIN, POLLIN); - }); - - notify.WaitForNotification(); - // Sleep ensures that poll begins waiting before we write to the FD. - absl::SleepFor(absl::Seconds(1)); - - char s[] = "foo\n"; - ASSERT_THAT(WriteFd(replica_.get(), s, strlen(s) + 1), SyscallSucceeds()); -} - -TEST_F(PtyTest, TermiosINLCR) { - struct kernel_termios t = DefaultTermios(); - t.c_iflag |= INLCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - char c = '\n'; - ASSERT_THAT(WriteFd(master_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - ExpectReadable(replica_, 1, &c); - EXPECT_EQ(c, '\r'); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, TermiosONOCR) { - struct kernel_termios t = DefaultTermios(); - t.c_oflag |= ONOCR; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - // The terminal is at column 0, so there should be no CR to read. - char c = '\r'; - ASSERT_THAT(WriteFd(replica_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - // Nothing to read. - ASSERT_THAT(PollAndReadFd(master_.get(), &c, 1, kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); - - // This time the column is greater than 0, so we should be able to read the CR - // out of the other end. - constexpr char kInput[] = "foo\r"; - constexpr int kInputSize = sizeof(kInput) - 1; - ASSERT_THAT(WriteFd(replica_.get(), kInput, kInputSize), - SyscallSucceedsWithValue(kInputSize)); - - char buf[kInputSize] = {}; - ExpectReadable(master_, kInputSize, buf); - - EXPECT_EQ(memcmp(buf, kInput, kInputSize), 0); - - ExpectFinished(master_); - - // Terminal should be at column 0 again, so no CR can be read. - ASSERT_THAT(WriteFd(replica_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - // Nothing to read. - ASSERT_THAT(PollAndReadFd(master_.get(), &c, 1, kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); -} - -TEST_F(PtyTest, TermiosOCRNL) { - struct kernel_termios t = DefaultTermios(); - t.c_oflag |= OCRNL; - t.c_lflag &= ~ICANON; // for byte-by-byte reading. - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - - // The terminal is at column 0, so there should be no CR to read. - char c = '\r'; - ASSERT_THAT(WriteFd(replica_.get(), &c, 1), SyscallSucceedsWithValue(1)); - - ExpectReadable(master_, 1, &c); - EXPECT_EQ(c, '\n'); - - ExpectFinished(master_); -} - -// Tests that VEOL is disabled when we start, and that we can set it to enable -// it. -TEST_F(PtyTest, VEOLTermination) { - // Write a few bytes ending with '\0', and confirm that we can't read. - constexpr char kInput[] = "hello"; - ASSERT_THAT(WriteFd(master_.get(), kInput, sizeof(kInput)), - SyscallSucceedsWithValue(sizeof(kInput))); - char buf[sizeof(kInput)] = {}; - ASSERT_THAT(PollAndReadFd(replica_.get(), buf, sizeof(kInput), kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); - - // Set the EOL character to '=' and write it. - constexpr char delim = '='; - struct kernel_termios t = DefaultTermios(); - t.c_cc[VEOL] = delim; - ASSERT_THAT(ioctl(replica_.get(), TCSETS, &t), SyscallSucceeds()); - ASSERT_THAT(WriteFd(master_.get(), &delim, 1), SyscallSucceedsWithValue(1)); - - // Now we can read, as sending EOL caused the line to become available. - ExpectReadable(replica_, sizeof(kInput), buf); - EXPECT_EQ(memcmp(buf, kInput, sizeof(kInput)), 0); - - ExpectReadable(replica_, 1, buf); - EXPECT_EQ(buf[0], '='); - - ExpectFinished(replica_); -} - -// Tests that we can write more than the 4096 character limit, then a -// terminating character, then read out just the first 4095 bytes plus the -// terminator. -TEST_F(PtyTest, CanonBigWrite) { - constexpr int kWriteLen = kMaxLineSize + 4; - char input[kWriteLen]; - memset(input, 'M', kWriteLen - 1); - input[kWriteLen - 1] = '\n'; - ASSERT_THAT(WriteFd(master_.get(), input, kWriteLen), - SyscallSucceedsWithValue(kWriteLen)); - - // We can read the line. - char buf[kMaxLineSize] = {}; - ExpectReadable(replica_, kMaxLineSize, buf); - - ExpectFinished(replica_); -} - -// Tests that data written in canonical mode can be read immediately once -// switched to noncanonical mode. -TEST_F(PtyTest, SwitchCanonToNoncanon) { - // Write a few bytes without a terminating character, switch to noncanonical - // mode, and read them. - constexpr char kInput[] = "hello"; - ASSERT_THAT(WriteFd(master_.get(), kInput, sizeof(kInput)), - SyscallSucceedsWithValue(sizeof(kInput))); - - // Nothing available yet. - char buf[sizeof(kInput)] = {}; - ASSERT_THAT(PollAndReadFd(replica_.get(), buf, sizeof(kInput), kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); - - DisableCanonical(); - - ExpectReadable(replica_, sizeof(kInput), buf); - EXPECT_STREQ(buf, kInput); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchCanonToNonCanonNewline) { - // Write a few bytes with a terminating character. - constexpr char kInput[] = "hello\n"; - ASSERT_THAT(WriteFd(master_.get(), kInput, sizeof(kInput)), - SyscallSucceedsWithValue(sizeof(kInput))); - - DisableCanonical(); - - // We can read the line. - char buf[sizeof(kInput)] = {}; - ExpectReadable(replica_, sizeof(kInput), buf); - EXPECT_STREQ(buf, kInput); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchNoncanonToCanonNewlineBig) { - DisableCanonical(); - - // Write more than the maximum line size, then write a delimiter. - constexpr int kWriteLen = 4100; - char input[kWriteLen]; - memset(input, 'M', kWriteLen); - ASSERT_THAT(WriteFd(master_.get(), input, kWriteLen), - SyscallSucceedsWithValue(kWriteLen)); - // Wait for the input queue to fill. - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), kMaxLineSize - 1)); - constexpr char delim = '\n'; - ASSERT_THAT(WriteFd(master_.get(), &delim, 1), SyscallSucceedsWithValue(1)); - - EnableCanonical(); - - // We can read the line. - char buf[kMaxLineSize] = {}; - ExpectReadable(replica_, kMaxLineSize - 1, buf); - - // We can also read the remaining characters. - ExpectReadable(replica_, 6, buf); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchNoncanonToCanonNoNewline) { - DisableCanonical(); - - // Write a few bytes without a terminating character. - // mode, and read them. - constexpr char kInput[] = "hello"; - ASSERT_THAT(WriteFd(master_.get(), kInput, sizeof(kInput) - 1), - SyscallSucceedsWithValue(sizeof(kInput) - 1)); - - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), sizeof(kInput) - 1)); - EnableCanonical(); - - // We can read the line. - char buf[sizeof(kInput)] = {}; - ExpectReadable(replica_, sizeof(kInput) - 1, buf); - EXPECT_STREQ(buf, kInput); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchNoncanonToCanonNoNewlineBig) { - DisableCanonical(); - - // Write a few bytes without a terminating character. - // mode, and read them. - constexpr int kWriteLen = 4100; - char input[kWriteLen]; - memset(input, 'M', kWriteLen); - ASSERT_THAT(WriteFd(master_.get(), input, kWriteLen), - SyscallSucceedsWithValue(kWriteLen)); - - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), kMaxLineSize - 1)); - EnableCanonical(); - - // We can read the line. - char buf[kMaxLineSize] = {}; - ExpectReadable(replica_, kMaxLineSize - 1, buf); - - ExpectFinished(replica_); -} - -// Tests that we can write over the 4095 noncanonical limit, then read out -// everything. -TEST_F(PtyTest, NoncanonBigWrite) { - DisableCanonical(); - - // Write well over the 4095 internal buffer limit. - constexpr char kInput = 'M'; - constexpr int kInputSize = kMaxLineSize * 2; - for (int i = 0; i < kInputSize; i++) { - // This makes too many syscalls for save/restore. - const DisableSave ds; - ASSERT_THAT(WriteFd(master_.get(), &kInput, sizeof(kInput)), - SyscallSucceedsWithValue(sizeof(kInput))); - } - - // We should be able to read out everything. Sleep a bit so that Linux has a - // chance to move data from the master to the replica. - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), kMaxLineSize - 1)); - for (int i = 0; i < kInputSize; i++) { - // This makes too many syscalls for save/restore. - const DisableSave ds; - char c; - ExpectReadable(replica_, 1, &c); - ASSERT_EQ(c, kInput); - } - - ExpectFinished(replica_); -} - -// ICANON doesn't make input available until a line delimiter is typed. -// -// Test newline. -TEST_F(PtyTest, TermiosICANONNewline) { - char input[3] = {'a', 'b', 'c'}; - ASSERT_THAT(WriteFd(master_.get(), input, sizeof(input)), - SyscallSucceedsWithValue(sizeof(input))); - - // Extra bytes for newline (written later) and NUL for EXPECT_STREQ. - char buf[5] = {}; - - // Nothing available yet. - ASSERT_THAT(PollAndReadFd(replica_.get(), buf, sizeof(input), kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); - - char delim = '\n'; - ASSERT_THAT(WriteFd(master_.get(), &delim, 1), SyscallSucceedsWithValue(1)); - - // Now it is available. - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), sizeof(input) + 1)); - ExpectReadable(replica_, sizeof(input) + 1, buf); - EXPECT_STREQ(buf, "abc\n"); - - ExpectFinished(replica_); -} - -// ICANON doesn't make input available until a line delimiter is typed. -// -// Test EOF (^D). -TEST_F(PtyTest, TermiosICANONEOF) { - char input[3] = {'a', 'b', 'c'}; - ASSERT_THAT(WriteFd(master_.get(), input, sizeof(input)), - SyscallSucceedsWithValue(sizeof(input))); - - // Extra byte for NUL for EXPECT_STREQ. - char buf[4] = {}; - - // Nothing available yet. - ASSERT_THAT(PollAndReadFd(replica_.get(), buf, sizeof(input), kTimeout), - PosixErrorIs(ETIMEDOUT, ::testing::StrEq("Poll timed out"))); - char delim = ControlCharacter('D'); - ASSERT_THAT(WriteFd(master_.get(), &delim, 1), SyscallSucceedsWithValue(1)); - - // Now it is available. Note that ^D is not included. - ExpectReadable(replica_, sizeof(input), buf); - EXPECT_STREQ(buf, "abc"); - - ExpectFinished(replica_); -} - -// ICANON limits us to 4096 bytes including a terminating character. Anything -// after and 4095th character is discarded (although still processed for -// signals and echoing). -TEST_F(PtyTest, CanonDiscard) { - constexpr char kInput = 'M'; - constexpr int kInputSize = 4100; - constexpr int kIter = 3; - - // A few times write more than the 4096 character maximum, then a newline. - constexpr char delim = '\n'; - for (int i = 0; i < kIter; i++) { - // This makes too many syscalls for save/restore. - const DisableSave ds; - for (int i = 0; i < kInputSize; i++) { - ASSERT_THAT(WriteFd(master_.get(), &kInput, sizeof(kInput)), - SyscallSucceedsWithValue(sizeof(kInput))); - } - ASSERT_THAT(WriteFd(master_.get(), &delim, 1), SyscallSucceedsWithValue(1)); - } - - // There should be multiple truncated lines available to read. - for (int i = 0; i < kIter; i++) { - char buf[kInputSize] = {}; - ExpectReadable(replica_, kMaxLineSize, buf); - EXPECT_EQ(buf[kMaxLineSize - 1], delim); - EXPECT_EQ(buf[kMaxLineSize - 2], kInput); - } - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, CanonMultiline) { - constexpr char kInput1[] = "GO\n"; - constexpr char kInput2[] = "BLUE\n"; - - // Write both lines. - ASSERT_THAT(WriteFd(master_.get(), kInput1, sizeof(kInput1) - 1), - SyscallSucceedsWithValue(sizeof(kInput1) - 1)); - ASSERT_THAT(WriteFd(master_.get(), kInput2, sizeof(kInput2) - 1), - SyscallSucceedsWithValue(sizeof(kInput2) - 1)); - - // Get the first line. - char line1[8] = {}; - ExpectReadable(replica_, sizeof(kInput1) - 1, line1); - EXPECT_STREQ(line1, kInput1); - - // Get the second line. - char line2[8] = {}; - ExpectReadable(replica_, sizeof(kInput2) - 1, line2); - EXPECT_STREQ(line2, kInput2); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchNoncanonToCanonMultiline) { - DisableCanonical(); - - constexpr char kInput1[] = "GO\n"; - constexpr char kInput2[] = "BLUE\n"; - constexpr char kExpected[] = "GO\nBLUE\n"; - - // Write both lines. - ASSERT_THAT(WriteFd(master_.get(), kInput1, sizeof(kInput1) - 1), - SyscallSucceedsWithValue(sizeof(kInput1) - 1)); - ASSERT_THAT(WriteFd(master_.get(), kInput2, sizeof(kInput2) - 1), - SyscallSucceedsWithValue(sizeof(kInput2) - 1)); - - ASSERT_NO_ERRNO( - WaitUntilReceived(replica_.get(), sizeof(kInput1) + sizeof(kInput2) - 2)); - EnableCanonical(); - - // Get all together as one line. - char line[9] = {}; - ExpectReadable(replica_, 8, line); - EXPECT_STREQ(line, kExpected); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, SwitchTwiceMultiline) { - std::string kInputs[] = {"GO\n", "BLUE\n", "!"}; - std::string kExpected = "GO\nBLUE\n!"; - - // Write each line. - for (const std::string& input : kInputs) { - ASSERT_THAT(WriteFd(master_.get(), input.c_str(), input.size()), - SyscallSucceedsWithValue(input.size())); - } - - DisableCanonical(); - // All written characters have to make it into the input queue before - // canonical mode is re-enabled. If the final '!' character hasn't been - // enqueued before canonical mode is re-enabled, it won't be readable. - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), kExpected.size())); - EnableCanonical(); - - // Get all together as one line. - char line[10] = {}; - ExpectReadable(replica_, 9, line); - EXPECT_STREQ(line, kExpected.c_str()); - - ExpectFinished(replica_); -} - -TEST_F(PtyTest, QueueSize) { - // Write the line. - constexpr char kInput1[] = "GO\n"; - ASSERT_THAT(WriteFd(master_.get(), kInput1, sizeof(kInput1) - 1), - SyscallSucceedsWithValue(sizeof(kInput1) - 1)); - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), sizeof(kInput1) - 1)); - - // Ensure that writing more (beyond what is readable) does not impact the - // readable size. - char input[kMaxLineSize]; - memset(input, 'M', kMaxLineSize); - ASSERT_THAT(WriteFd(master_.get(), input, kMaxLineSize), - SyscallSucceedsWithValue(kMaxLineSize)); - int inputBufSize = ASSERT_NO_ERRNO_AND_VALUE( - WaitUntilReceived(replica_.get(), sizeof(kInput1) - 1)); - EXPECT_EQ(inputBufSize, sizeof(kInput1) - 1); -} - -TEST_F(PtyTest, PartialBadBuffer) { - // Allocate 2 pages. - void* addr = mmap(nullptr, 2 * kPageSize, PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - ASSERT_NE(addr, MAP_FAILED); - char* buf = reinterpret_cast<char*>(addr); - - // Guard the 2nd page for our read to run into. - ASSERT_THAT( - mprotect(reinterpret_cast<void*>(buf + kPageSize), kPageSize, PROT_NONE), - SyscallSucceeds()); - - // Leave only one free byte in the buffer. - char* bad_buffer = buf + kPageSize - 1; - - // Write to the master. - constexpr char kBuf[] = "hello\n"; - constexpr size_t size = sizeof(kBuf) - 1; - EXPECT_THAT(WriteFd(master_.get(), kBuf, size), - SyscallSucceedsWithValue(size)); - - // Read from the replica into bad_buffer. - ASSERT_NO_ERRNO(WaitUntilReceived(replica_.get(), size)); - EXPECT_THAT(ReadFd(replica_.get(), bad_buffer, size), - SyscallFailsWithErrno(EFAULT)); - - EXPECT_THAT(munmap(addr, 2 * kPageSize), SyscallSucceeds()) << addr; -} - -TEST_F(PtyTest, SimpleEcho) { - constexpr char kInput[] = "Mr. Eko"; - EXPECT_THAT(WriteFd(master_.get(), kInput, strlen(kInput)), - SyscallSucceedsWithValue(strlen(kInput))); - - char buf[100] = {}; - ExpectReadable(master_, strlen(kInput), buf); - - EXPECT_STREQ(buf, kInput); - ExpectFinished(master_); -} - -TEST_F(PtyTest, GetWindowSize) { - struct winsize ws; - ASSERT_THAT(ioctl(replica_.get(), TIOCGWINSZ, &ws), SyscallSucceeds()); - EXPECT_EQ(ws.ws_row, 0); - EXPECT_EQ(ws.ws_col, 0); -} - -TEST_F(PtyTest, SetReplicaWindowSize) { - constexpr uint16_t kRows = 343; - constexpr uint16_t kCols = 2401; - struct winsize ws = {.ws_row = kRows, .ws_col = kCols}; - ASSERT_THAT(ioctl(replica_.get(), TIOCSWINSZ, &ws), SyscallSucceeds()); - - struct winsize retrieved_ws = {}; - ASSERT_THAT(ioctl(master_.get(), TIOCGWINSZ, &retrieved_ws), - SyscallSucceeds()); - EXPECT_EQ(retrieved_ws.ws_row, kRows); - EXPECT_EQ(retrieved_ws.ws_col, kCols); -} - -TEST_F(PtyTest, SetMasterWindowSize) { - constexpr uint16_t kRows = 343; - constexpr uint16_t kCols = 2401; - struct winsize ws = {.ws_row = kRows, .ws_col = kCols}; - ASSERT_THAT(ioctl(master_.get(), TIOCSWINSZ, &ws), SyscallSucceeds()); - - struct winsize retrieved_ws = {}; - ASSERT_THAT(ioctl(replica_.get(), TIOCGWINSZ, &retrieved_ws), - SyscallSucceeds()); - EXPECT_EQ(retrieved_ws.ws_row, kRows); - EXPECT_EQ(retrieved_ws.ws_col, kCols); -} - -class JobControlTest : public ::testing::Test { - protected: - void SetUp() override { - master_ = ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/ptmx", O_RDWR | O_NONBLOCK)); - replica_ = ASSERT_NO_ERRNO_AND_VALUE(OpenReplica(master_)); - - // Make this a session leader, which also drops the controlling terminal. - // In the gVisor test environment, this test will be run as the session - // leader already (as the sentry init process). - if (!IsRunningOnGvisor()) { - ASSERT_THAT(setsid(), SyscallSucceeds()); - } - } - - PosixError RunInChild(SubprocessCallback childFunc) { - pid_t child = fork(); - if (!child) { - childFunc(); - _exit(0); - } - int wstatus; - if (waitpid(child, &wstatus, 0) != child) { - return PosixError( - errno, absl::StrCat("child failed with wait status: ", wstatus)); - } - return PosixError(wstatus, "process returned"); - } - - // Master and replica ends of the PTY. Non-blocking. - FileDescriptor master_; - FileDescriptor replica_; -}; - -TEST_F(JobControlTest, SetTTYMaster) { - auto res = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(master_.get(), TIOCSCTTY, 0)); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetTTY) { - auto res = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(ioctl(!replica_.get(), TIOCSCTTY, 0)); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetTTYNonLeader) { - // Fork a process that won't be the session leader. - auto res = - RunInChild([=]() { TEST_PCHECK(ioctl(replica_.get(), TIOCSCTTY, 0)); }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetTTYBadArg) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - auto res = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 1)); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetTTYDifferentSession) { - SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto res = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 1)); - - // Fork, join a new session, and try to steal the parent's controlling - // terminal, which should fail. - pid_t grandchild = fork(); - if (!grandchild) { - TEST_PCHECK(setsid() >= 0); - // We shouldn't be able to steal the terminal. - TEST_PCHECK(ioctl(replica_.get(), TIOCSCTTY, 1)); - _exit(0); - } - - int gcwstatus; - TEST_PCHECK(waitpid(grandchild, &gcwstatus, 0) == grandchild); - TEST_PCHECK(gcwstatus == 0); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, ReleaseTTY) { - ASSERT_THAT(ioctl(replica_.get(), TIOCSCTTY, 0), SyscallSucceeds()); - - // Make sure we're ignoring SIGHUP, which will be sent to this process once we - // disconnect they TTY. - struct sigaction sa = {}; - sa.sa_handler = SIG_IGN; - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - struct sigaction old_sa; - EXPECT_THAT(sigaction(SIGHUP, &sa, &old_sa), SyscallSucceeds()); - EXPECT_THAT(ioctl(replica_.get(), TIOCNOTTY), SyscallSucceeds()); - EXPECT_THAT(sigaction(SIGHUP, &old_sa, NULL), SyscallSucceeds()); -} - -TEST_F(JobControlTest, ReleaseUnsetTTY) { - ASSERT_THAT(ioctl(replica_.get(), TIOCNOTTY), SyscallFailsWithErrno(ENOTTY)); -} - -TEST_F(JobControlTest, ReleaseWrongTTY) { - auto res = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - TEST_PCHECK(ioctl(master_.get(), TIOCNOTTY) < 0 && errno == ENOTTY); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, ReleaseTTYNonLeader) { - auto ret = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - pid_t grandchild = fork(); - if (!grandchild) { - TEST_PCHECK(!ioctl(replica_.get(), TIOCNOTTY)); - _exit(0); - } - - int wstatus; - TEST_PCHECK(waitpid(grandchild, &wstatus, 0) == grandchild); - TEST_PCHECK(wstatus == 0); - }); - ASSERT_NO_ERRNO(ret); -} - -TEST_F(JobControlTest, ReleaseTTYDifferentSession) { - auto ret = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - pid_t grandchild = fork(); - if (!grandchild) { - // Join a new session, then try to disconnect. - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(ioctl(replica_.get(), TIOCNOTTY)); - _exit(0); - } - - int wstatus; - TEST_PCHECK(waitpid(grandchild, &wstatus, 0) == grandchild); - TEST_PCHECK(wstatus == 0); - }); - ASSERT_NO_ERRNO(ret); -} - -// Used by the child process spawned in ReleaseTTYSignals to track received -// signals. -static int received; - -void sig_handler(int signum) { received |= signum; } - -// When the session leader releases its controlling terminal, the foreground -// process group gets SIGHUP, then SIGCONT. This test: -// - Spawns 2 threads -// - Has thread 1 return 0 if it gets both SIGHUP and SIGCONT -// - Has thread 2 leave the foreground process group, and return non-zero if it -// receives any signals. -// - Has the parent thread release its controlling terminal -// - Checks that thread 1 got both signals -// - Checks that thread 2 didn't get any signals. -TEST_F(JobControlTest, ReleaseTTYSignals) { - ASSERT_THAT(ioctl(replica_.get(), TIOCSCTTY, 0), SyscallSucceeds()); - - received = 0; - struct sigaction sa = {}; - sa.sa_handler = sig_handler; - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - sigaddset(&sa.sa_mask, SIGHUP); - sigaddset(&sa.sa_mask, SIGCONT); - sigprocmask(SIG_BLOCK, &sa.sa_mask, NULL); - - pid_t same_pgrp_child = fork(); - if (!same_pgrp_child) { - // The child will wait for SIGHUP and SIGCONT, then return 0. It begins with - // SIGHUP and SIGCONT blocked. We install signal handlers for those signals, - // then use sigsuspend to wait for those specific signals. - TEST_PCHECK(!sigaction(SIGHUP, &sa, NULL)); - TEST_PCHECK(!sigaction(SIGCONT, &sa, NULL)); - sigset_t mask; - sigfillset(&mask); - sigdelset(&mask, SIGHUP); - sigdelset(&mask, SIGCONT); - while (received != (SIGHUP | SIGCONT)) { - sigsuspend(&mask); - } - _exit(0); - } - - // We don't want to block these anymore. - sigprocmask(SIG_UNBLOCK, &sa.sa_mask, NULL); - - // This child will return non-zero if either SIGHUP or SIGCONT are received. - pid_t diff_pgrp_child = fork(); - if (!diff_pgrp_child) { - TEST_PCHECK(!setpgid(0, 0)); - TEST_PCHECK(pause()); - _exit(1); - } - - EXPECT_THAT(setpgid(diff_pgrp_child, diff_pgrp_child), SyscallSucceeds()); - - // Make sure we're ignoring SIGHUP, which will be sent to this process once we - // disconnect they TTY. - struct sigaction sighup_sa = {}; - sighup_sa.sa_handler = SIG_IGN; - sighup_sa.sa_flags = 0; - sigemptyset(&sighup_sa.sa_mask); - struct sigaction old_sa; - EXPECT_THAT(sigaction(SIGHUP, &sighup_sa, &old_sa), SyscallSucceeds()); - - // Release the controlling terminal, sending SIGHUP and SIGCONT to all other - // processes in this process group. - EXPECT_THAT(ioctl(replica_.get(), TIOCNOTTY), SyscallSucceeds()); - - EXPECT_THAT(sigaction(SIGHUP, &old_sa, NULL), SyscallSucceeds()); - - // The child in the same process group will get signaled. - int wstatus; - EXPECT_THAT(waitpid(same_pgrp_child, &wstatus, 0), - SyscallSucceedsWithValue(same_pgrp_child)); - EXPECT_EQ(wstatus, 0); - - // The other child will not get signaled. - EXPECT_THAT(waitpid(diff_pgrp_child, &wstatus, WNOHANG), - SyscallSucceedsWithValue(0)); - EXPECT_THAT(kill(diff_pgrp_child, SIGKILL), SyscallSucceeds()); -} - -TEST_F(JobControlTest, GetForegroundProcessGroup) { - auto res = RunInChild([=]() { - pid_t pid, foreground_pgid; - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 1)); - TEST_PCHECK(!ioctl(replica_.get(), TIOCGPGRP, &foreground_pgid)); - TEST_PCHECK((pid = getpid()) >= 0); - TEST_PCHECK(pid == foreground_pgid); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, GetForegroundProcessGroupNonControlling) { - // At this point there's no controlling terminal, so TIOCGPGRP should fail. - pid_t foreground_pgid; - ASSERT_THAT(ioctl(replica_.get(), TIOCGPGRP, &foreground_pgid), - SyscallFailsWithErrno(ENOTTY)); -} - -// This test: -// - sets itself as the foreground process group -// - creates a child process in a new process group -// - sets that child as the foreground process group -// - kills its child and sets itself as the foreground process group. -// TODO(gvisor.dev/issue/5357): Fix and enable. -TEST_F(JobControlTest, DISABLED_SetForegroundProcessGroup) { - auto res = RunInChild([=]() { - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - // Ignore SIGTTOU so that we don't stop ourself when calling tcsetpgrp. - struct sigaction sa = {}; - sa.sa_handler = SIG_IGN; - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - sigaction(SIGTTOU, &sa, NULL); - - // Set ourself as the foreground process group. - TEST_PCHECK(!tcsetpgrp(replica_.get(), getpgid(0))); - - // Create a new process that just waits to be signaled. - pid_t grandchild = fork(); - if (!grandchild) { - TEST_PCHECK(!pause()); - // We should never reach this. - _exit(1); - } - - // Make the child its own process group, then make it the controlling - // process group of the terminal. - TEST_PCHECK(!setpgid(grandchild, grandchild)); - TEST_PCHECK(!tcsetpgrp(replica_.get(), grandchild)); - - // Sanity check - we're still the controlling session. - TEST_PCHECK(getsid(0) == getsid(grandchild)); - - // Signal the child, wait for it to exit, then retake the terminal. - TEST_PCHECK(!kill(grandchild, SIGTERM)); - int wstatus; - TEST_PCHECK(waitpid(grandchild, &wstatus, 0) == grandchild); - TEST_PCHECK(WIFSIGNALED(wstatus)); - TEST_PCHECK(WTERMSIG(wstatus) == SIGTERM); - - // Set ourself as the foreground process. - pid_t pgid; - TEST_PCHECK(pgid = getpgid(0) == 0); - TEST_PCHECK(!tcsetpgrp(replica_.get(), pgid)); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetForegroundProcessGroupWrongTTY) { - pid_t pid = getpid(); - ASSERT_THAT(ioctl(replica_.get(), TIOCSPGRP, &pid), - SyscallFailsWithErrno(ENOTTY)); -} - -TEST_F(JobControlTest, SetForegroundProcessGroupNegPgid) { - auto ret = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - pid_t pid = -1; - TEST_PCHECK(ioctl(replica_.get(), TIOCSPGRP, &pid) && errno == EINVAL); - }); - ASSERT_NO_ERRNO(ret); -} - -// TODO(gvisor.dev/issue/5357): Fix and enable. -TEST_F(JobControlTest, DISABLED_SetForegroundProcessGroupEmptyProcessGroup) { - auto res = RunInChild([=]() { - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - // Create a new process, put it in a new process group, make that group the - // foreground process group, then have the process wait. - pid_t grandchild = fork(); - if (!grandchild) { - TEST_PCHECK(!setpgid(0, 0)); - _exit(0); - } - - // Wait for the child to exit. - int wstatus; - TEST_PCHECK(waitpid(grandchild, &wstatus, 0) == grandchild); - // The child's process group doesn't exist anymore - this should fail. - TEST_PCHECK(ioctl(replica_.get(), TIOCSPGRP, &grandchild) != 0 && - errno == ESRCH); - }); - ASSERT_NO_ERRNO(res); -} - -TEST_F(JobControlTest, SetForegroundProcessGroupDifferentSession) { - auto ret = RunInChild([=]() { - TEST_PCHECK(setsid() >= 0); - TEST_PCHECK(!ioctl(replica_.get(), TIOCSCTTY, 0)); - - int sync_setsid[2]; - int sync_exit[2]; - TEST_PCHECK(pipe(sync_setsid) >= 0); - TEST_PCHECK(pipe(sync_exit) >= 0); - - // Create a new process and put it in a new session. - pid_t grandchild = fork(); - if (!grandchild) { - TEST_PCHECK(setsid() >= 0); - // Tell the parent we're in a new session. - char c = 'c'; - TEST_PCHECK(WriteFd(sync_setsid[1], &c, 1) == 1); - TEST_PCHECK(ReadFd(sync_exit[0], &c, 1) == 1); - _exit(0); - } - - // Wait for the child to tell us it's in a new session. - char c = 'c'; - TEST_PCHECK(ReadFd(sync_setsid[0], &c, 1) == 1); - - // Child is in a new session, so we can't make it the foregroup process - // group. - TEST_PCHECK(ioctl(replica_.get(), TIOCSPGRP, &grandchild) && - errno == EPERM); - - TEST_PCHECK(WriteFd(sync_exit[1], &c, 1) == 1); - - int wstatus; - TEST_PCHECK(waitpid(grandchild, &wstatus, 0) == grandchild); - TEST_PCHECK(WIFEXITED(wstatus)); - TEST_PCHECK(!WEXITSTATUS(wstatus)); - }); - ASSERT_NO_ERRNO(ret); -} - -// Verify that we don't hang when creating a new session from an orphaned -// process group (b/139968068). Calling setsid() creates an orphaned process -// group, as process groups that contain the session's leading process are -// orphans. -// -// We create 2 sessions in this test. The init process in gVisor is considered -// not to be an orphan (see sessions.go), so we have to create a session from -// which to create a session. The latter session is being created from an -// orphaned process group. -TEST_F(JobControlTest, OrphanRegression) { - pid_t session_2_leader = fork(); - if (!session_2_leader) { - TEST_PCHECK(setsid() >= 0); - - pid_t session_3_leader = fork(); - if (!session_3_leader) { - TEST_PCHECK(setsid() >= 0); - - _exit(0); - } - - int wstatus; - TEST_PCHECK(waitpid(session_3_leader, &wstatus, 0) == session_3_leader); - TEST_PCHECK(wstatus == 0); - - _exit(0); - } - - int wstatus; - ASSERT_THAT(waitpid(session_2_leader, &wstatus, 0), - SyscallSucceedsWithValue(session_2_leader)); - ASSERT_EQ(wstatus, 0); -} - -} // namespace -} // namespace testing -} // namespace gvisor |