diff options
Diffstat (limited to 'src/shared')
| -rw-r--r-- | src/shared/ptyfwd.c | 534 | ||||
| -rw-r--r-- | src/shared/ptyfwd.h | 9 |
2 files changed, 277 insertions, 266 deletions
diff --git a/src/shared/ptyfwd.c b/src/shared/ptyfwd.c index d44d70bf9f..7c6e182e5b 100644 --- a/src/shared/ptyfwd.c +++ b/src/shared/ptyfwd.c @@ -28,13 +28,44 @@ #include "util.h" #include "ptyfwd.h" -#define ESCAPE_USEC USEC_PER_SEC +struct PTYForward { + sd_event *event; -static bool look_for_escape(usec_t *timestamp, unsigned *counter, const char *buffer, size_t n) { + int master; + + sd_event_source *stdin_event_source; + sd_event_source *stdout_event_source; + sd_event_source *master_event_source; + + sd_event_source *sigwinch_event_source; + + struct termios saved_stdin_attr; + struct termios saved_stdout_attr; + + bool saved_stdin:1; + bool saved_stdout:1; + + bool stdin_readable:1; + bool stdin_hangup:1; + bool stdout_writable:1; + bool stdout_hangup:1; + bool master_readable:1; + bool master_writable:1; + bool master_hangup:1; + + char in_buffer[LINE_MAX], out_buffer[LINE_MAX]; + size_t in_buffer_full, out_buffer_full; + + usec_t escape_timestamp; + unsigned escape_counter; +}; + +#define ESCAPE_USEC (1*USEC_PER_SEC) + +static bool look_for_escape(PTYForward *f, const char *buffer, size_t n) { const char *p; - assert(timestamp); - assert(counter); + assert(f); assert(buffer); assert(n > 0); @@ -44,343 +75,316 @@ static bool look_for_escape(usec_t *timestamp, unsigned *counter, const char *bu if (*p == 0x1D) { usec_t nw = now(CLOCK_MONOTONIC); - if (*counter == 0 || nw > *timestamp + USEC_PER_SEC) { - *timestamp = nw; - *counter = 1; + if (f->escape_counter == 0 || nw > f->escape_timestamp + ESCAPE_USEC) { + f->escape_timestamp = nw; + f->escape_counter = 1; } else { - (*counter)++; + (f->escape_counter)++; - if (*counter >= 3) + if (f->escape_counter >= 3) return true; } } else { - *timestamp = 0; - *counter = 0; + f->escape_timestamp = 0; + f->escape_counter = 0; } } return false; } -static int process_pty_loop(int master, sigset_t *mask, pid_t kill_pid, int signo) { - char in_buffer[LINE_MAX], out_buffer[LINE_MAX]; - size_t in_buffer_full = 0, out_buffer_full = 0; - struct epoll_event stdin_ev, stdout_ev, master_ev, signal_ev; - bool stdin_readable = false, stdout_writable = false, master_readable = false, master_writable = false; - bool stdin_hangup = false, stdout_hangup = false, master_hangup = false; - bool tried_orderly_shutdown = false, process_signalfd = false, quit = false; - usec_t escape_timestamp = 0; - unsigned escape_counter = 0; - _cleanup_close_ int ep = -1, signal_fd = -1; - - assert(master >= 0); - assert(mask); - assert(kill_pid == 0 || kill_pid > 1); - assert(signo >= 0 && signo < _NSIG); - - fd_nonblock(STDIN_FILENO, true); - fd_nonblock(STDOUT_FILENO, true); - fd_nonblock(master, true); - - signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC); - if (signal_fd < 0) { - log_error("signalfd(): %m"); - return -errno; - } - - ep = epoll_create1(EPOLL_CLOEXEC); - if (ep < 0) { - log_error("Failed to create epoll: %m"); - return -errno; - } +static int shovel(PTYForward *f) { + ssize_t k; - /* We read from STDIN only if this is actually a TTY, - * otherwise we assume non-interactivity. */ - if (isatty(STDIN_FILENO)) { - zero(stdin_ev); - stdin_ev.events = EPOLLIN|EPOLLET; - stdin_ev.data.fd = STDIN_FILENO; + assert(f); - if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0) { - log_error("Failed to register STDIN in epoll: %m"); - return -errno; - } - } + while ((f->stdin_readable && f->in_buffer_full <= 0) || + (f->master_writable && f->in_buffer_full > 0) || + (f->master_readable && f->out_buffer_full <= 0) || + (f->stdout_writable && f->out_buffer_full > 0)) { - zero(stdout_ev); - stdout_ev.events = EPOLLOUT|EPOLLET; - stdout_ev.data.fd = STDOUT_FILENO; + if (f->stdin_readable && f->in_buffer_full < LINE_MAX) { - zero(master_ev); - master_ev.events = EPOLLIN|EPOLLOUT|EPOLLET; - master_ev.data.fd = master; + k = read(STDIN_FILENO, f->in_buffer + f->in_buffer_full, LINE_MAX - f->in_buffer_full); + if (k < 0) { - zero(signal_ev); - signal_ev.events = EPOLLIN; - signal_ev.data.fd = signal_fd; + if (errno == EAGAIN) + f->stdin_readable = false; + else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) { + f->stdin_readable = false; + f->stdin_hangup = true; - if (epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0) { - if (errno != EPERM) { - log_error("Failed to register stdout in epoll: %m"); - return -errno; + f->stdin_event_source = sd_event_source_unref(f->stdin_event_source); + } else { + log_error("read(): %m"); + return sd_event_exit(f->event, EXIT_FAILURE); + } + } else if (k == 0) { + /* EOF on stdin */ + f->stdin_readable = false; + f->stdin_hangup = true; + + f->stdin_event_source = sd_event_source_unref(f->stdin_event_source); + } else { + /* Check if ^] has been + * pressed three times within + * one second. If we get this + * we quite immediately. */ + if (look_for_escape(f, f->in_buffer + f->in_buffer_full, k)) + return sd_event_exit(f->event, EXIT_FAILURE); + + f->in_buffer_full += (size_t) k; + } } - /* stdout without epoll support. Likely redirected to regular file. */ - stdout_writable = true; - } - - if (epoll_ctl(ep, EPOLL_CTL_ADD, master, &master_ev) < 0 || - epoll_ctl(ep, EPOLL_CTL_ADD, signal_fd, &signal_ev) < 0) { - log_error("Failed to register fds in epoll: %m"); - return -errno; - } - - for (;;) { - struct epoll_event ev[16]; - ssize_t k; - int i, nfds; + if (f->master_writable && f->in_buffer_full > 0) { - nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), quit ? 0 : -1); - if (nfds < 0) { + k = write(f->master, f->in_buffer, f->in_buffer_full); + if (k < 0) { - if (errno == EINTR || errno == EAGAIN) - continue; + if (errno == EAGAIN || errno == EIO) + f->master_writable = false; + else if (errno == EPIPE || errno == ECONNRESET) { + f->master_writable = f->master_readable = false; + f->master_hangup = true; - log_error("epoll_wait(): %m"); - return -errno; + f->master_event_source = sd_event_source_unref(f->master_event_source); + } else { + log_error("write(): %m"); + return sd_event_exit(f->event, EXIT_FAILURE); + } + } else { + assert(f->in_buffer_full >= (size_t) k); + memmove(f->in_buffer, f->in_buffer + k, f->in_buffer_full - k); + f->in_buffer_full -= k; + } } - if (nfds == 0) - return 0; - - for (i = 0; i < nfds; i++) { - if (ev[i].data.fd == STDIN_FILENO) { - - if (ev[i].events & (EPOLLIN|EPOLLHUP)) - stdin_readable = true; - - } else if (ev[i].data.fd == STDOUT_FILENO) { - - if (ev[i].events & (EPOLLOUT|EPOLLHUP)) - stdout_writable = true; + if (f->master_readable && f->out_buffer_full < LINE_MAX) { - } else if (ev[i].data.fd == master) { + k = read(f->master, f->out_buffer + f->out_buffer_full, LINE_MAX - f->out_buffer_full); + if (k < 0) { - if (ev[i].events & (EPOLLIN|EPOLLHUP)) - master_readable = true; + /* Note that EIO on the master device + * might be cause by vhangup() or + * temporary closing of everything on + * the other side, we treat it like + * EAGAIN here and try again. */ - if (ev[i].events & (EPOLLOUT|EPOLLHUP)) - master_writable = true; + if (errno == EAGAIN || errno == EIO) + f->master_readable = false; + else if (errno == EPIPE || errno == ECONNRESET) { + f->master_readable = f->master_writable = false; + f->master_hangup = true; - } else if (ev[i].data.fd == signal_fd) - process_signalfd = true; - } - - while ((stdin_readable && in_buffer_full <= 0) || - (master_writable && in_buffer_full > 0) || - (master_readable && out_buffer_full <= 0) || - (stdout_writable && out_buffer_full > 0)) { - - if (stdin_readable && in_buffer_full < LINE_MAX) { - - k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full); - if (k < 0) { - - if (errno == EAGAIN) - stdin_readable = false; - else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) { - stdin_readable = false; - stdin_hangup = true; - epoll_ctl(ep, EPOLL_CTL_DEL, STDIN_FILENO, NULL); - } else { - log_error("read(): %m"); - return -errno; - } + f->master_event_source = sd_event_source_unref(f->master_event_source); } else { - /* Check if ^] has been - * pressed three times within - * one second. If we get this - * we quite immediately. */ - if (look_for_escape(&escape_timestamp, &escape_counter, in_buffer + in_buffer_full, k)) - return !quit; - - in_buffer_full += (size_t) k; + log_error("read(): %m"); + return sd_event_exit(f->event, EXIT_FAILURE); } - } - - if (master_writable && in_buffer_full > 0) { + } else + f->out_buffer_full += (size_t) k; + } - k = write(master, in_buffer, in_buffer_full); - if (k < 0) { + if (f->stdout_writable && f->out_buffer_full > 0) { - if (errno == EAGAIN || errno == EIO) - master_writable = false; - else if (errno == EPIPE || errno == ECONNRESET) { - master_writable = master_readable = false; - master_hangup = true; - epoll_ctl(ep, EPOLL_CTL_DEL, master, NULL); - } else { - log_error("write(): %m"); - return -errno; - } + k = write(STDOUT_FILENO, f->out_buffer, f->out_buffer_full); + if (k < 0) { + if (errno == EAGAIN) + f->stdout_writable = false; + else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) { + f->stdout_writable = false; + f->stdout_hangup = true; + f->stdout_event_source = sd_event_source_unref(f->stdout_event_source); } else { - assert(in_buffer_full >= (size_t) k); - memmove(in_buffer, in_buffer + k, in_buffer_full - k); - in_buffer_full -= k; + log_error("write(): %m"); + return sd_event_exit(f->event, EXIT_FAILURE); } - } - if (master_readable && out_buffer_full < LINE_MAX) { - - k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full); - if (k < 0) { - - /* Note that EIO on the master - * device might be cause by - * vhangup() or temporary - * closing of everything on - * the other side, we treat it - * like EAGAIN here and try - * again. */ - - if (errno == EAGAIN || errno == EIO) - master_readable = false; - else if (errno == EPIPE || errno == ECONNRESET) { - master_readable = master_writable = false; - master_hangup = true; - epoll_ctl(ep, EPOLL_CTL_DEL, master, NULL); - } else { - log_error("read(): %m"); - return -errno; - } - } else - out_buffer_full += (size_t) k; + } else { + assert(f->out_buffer_full >= (size_t) k); + memmove(f->out_buffer, f->out_buffer + k, f->out_buffer_full - k); + f->out_buffer_full -= k; } + } + } + + if (f->stdin_hangup || f->stdout_hangup || f->master_hangup) { + /* Exit the loop if any side hung up and if there's + * nothing more to write or nothing we could write. */ - if (stdout_writable && out_buffer_full > 0) { + if ((f->out_buffer_full <= 0 || f->stdout_hangup) && + (f->in_buffer_full <= 0 || f->master_hangup)) + return sd_event_exit(f->event, EXIT_SUCCESS); + } - k = write(STDOUT_FILENO, out_buffer, out_buffer_full); - if (k < 0) { + return 0; +} - if (errno == EAGAIN) - stdout_writable = false; - else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) { - stdout_writable = false; - stdout_hangup = true; - epoll_ctl(ep, EPOLL_CTL_DEL, STDOUT_FILENO, NULL); - } else { - log_error("write(): %m"); - return -errno; - } +static int on_master_event(sd_event_source *e, int fd, uint32_t revents, void *userdata) { + PTYForward *f = userdata; - } else { - assert(out_buffer_full >= (size_t) k); - memmove(out_buffer, out_buffer + k, out_buffer_full - k); - out_buffer_full -= k; - } - } + assert(f); + assert(e); + assert(e == f->master_event_source); + assert(fd >= 0); + assert(fd == f->master); - } + if (revents & (EPOLLIN|EPOLLHUP)) + f->master_readable = true; - if (process_signalfd) { - struct signalfd_siginfo sfsi; - ssize_t n; + if (revents & (EPOLLOUT|EPOLLHUP)) + f->master_writable = true; - n = read(signal_fd, &sfsi, sizeof(sfsi)); - if (n != sizeof(sfsi)) { + return shovel(f); +} - if (n >= 0) { - log_error("Failed to read from signalfd: invalid block size"); - return -EIO; - } +static int on_stdin_event(sd_event_source *e, int fd, uint32_t revents, void *userdata) { + PTYForward *f = userdata; - if (errno != EINTR && errno != EAGAIN) { - log_error("Failed to read from signalfd: %m"); - return -errno; - } - } else { + assert(f); + assert(e); + assert(e == f->stdin_event_source); + assert(fd >= 0); + assert(fd == STDIN_FILENO); - if (sfsi.ssi_signo == SIGWINCH) { - struct winsize ws; + if (revents & (EPOLLIN|EPOLLHUP)) + f->stdin_readable = true; - /* The window size changed, let's forward that. */ - if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) >= 0) - ioctl(master, TIOCSWINSZ, &ws); + return shovel(f); +} - } else if (sfsi.ssi_signo == SIGTERM && kill_pid > 0 && signo > 0 && !tried_orderly_shutdown) { +static int on_stdout_event(sd_event_source *e, int fd, uint32_t revents, void *userdata) { + PTYForward *f = userdata; - if (kill(kill_pid, signo) < 0) - quit = true; - else { - log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination."); + assert(f); + assert(e); + assert(e == f->stdout_event_source); + assert(fd >= 0); + assert(fd == STDOUT_FILENO); - /* This only works for systemd... */ - tried_orderly_shutdown = true; - } + if (revents & (EPOLLOUT|EPOLLHUP)) + f->stdout_writable = true; - } else - /* Signals that where - * delivered via signalfd that - * we didn't know are a reason - * for us to quit */ - quit = true; - } - } + return shovel(f); +} - if (stdin_hangup || stdout_hangup || master_hangup) { - /* Exit the loop if any side hung up and if - * there's nothing more to write or nothing we - * could write. */ +static int on_sigwinch_event(sd_event_source *e, const struct signalfd_siginfo *si, void *userdata) { + PTYForward *f = userdata; + struct winsize ws; - if ((out_buffer_full <= 0 || stdout_hangup) && - (in_buffer_full <= 0 || master_hangup)) - return !quit; - } - } + assert(f); + assert(e); + assert(e == f->sigwinch_event_source); + + /* The window size changed, let's forward that. */ + if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) >= 0) + ioctl(f->master, TIOCSWINSZ, &ws); + + return 0; } -int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) { - struct termios saved_stdin_attr, raw_stdin_attr; - struct termios saved_stdout_attr, raw_stdout_attr; - bool saved_stdin = false; - bool saved_stdout = false; +int pty_forward_new(sd_event *event, int master, PTYForward **ret) { + _cleanup_(pty_forward_freep) PTYForward *f = NULL; struct winsize ws; int r; + f = new0(PTYForward, 1); + if (!f) + return -ENOMEM; + + if (event) + f->event = sd_event_ref(event); + else { + r = sd_event_default(&f->event); + if (r < 0) + return r; + } + + r = fd_nonblock(STDIN_FILENO, true); + if (r < 0) + return r; + + r = fd_nonblock(STDOUT_FILENO, true); + if (r < 0) + return r; + + r = fd_nonblock(master, true); + if (r < 0) + return r; + + f->master = master; + if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) >= 0) ioctl(master, TIOCSWINSZ, &ws); - if (tcgetattr(STDIN_FILENO, &saved_stdin_attr) >= 0) { - saved_stdin = true; + if (tcgetattr(STDIN_FILENO, &f->saved_stdin_attr) >= 0) { + struct termios raw_stdin_attr; - raw_stdin_attr = saved_stdin_attr; + f->saved_stdin = true; + + raw_stdin_attr = f->saved_stdin_attr; cfmakeraw(&raw_stdin_attr); - raw_stdin_attr.c_oflag = saved_stdin_attr.c_oflag; + raw_stdin_attr.c_oflag = f->saved_stdin_attr.c_oflag; tcsetattr(STDIN_FILENO, TCSANOW, &raw_stdin_attr); } - if (tcgetattr(STDOUT_FILENO, &saved_stdout_attr) >= 0) { - saved_stdout = true; - raw_stdout_attr = saved_stdout_attr; + if (tcgetattr(STDOUT_FILENO, &f->saved_stdout_attr) >= 0) { + struct termios raw_stdout_attr; + + f->saved_stdout = true; + + raw_stdout_attr = f->saved_stdout_attr; cfmakeraw(&raw_stdout_attr); - raw_stdout_attr.c_iflag = saved_stdout_attr.c_iflag; - raw_stdout_attr.c_lflag = saved_stdout_attr.c_lflag; + raw_stdout_attr.c_iflag = f->saved_stdout_attr.c_iflag; + raw_stdout_attr.c_lflag = f->saved_stdout_attr.c_lflag; tcsetattr(STDOUT_FILENO, TCSANOW, &raw_stdout_attr); } - r = process_pty_loop(master, mask, kill_pid, signo); + r = sd_event_add_io(f->event, &f->master_event_source, master, EPOLLIN|EPOLLOUT|EPOLLET, on_master_event, f); + if (r < 0) + return r; - if (saved_stdout) - tcsetattr(STDOUT_FILENO, TCSANOW, &saved_stdout_attr); - if (saved_stdin) - tcsetattr(STDIN_FILENO, TCSANOW, &saved_stdin_attr); + r = sd_event_add_io(f->event, &f->stdin_event_source, STDIN_FILENO, EPOLLIN|EPOLLET, on_stdin_event, f); + if (r < 0 && r != -EPERM) + return r; + + r = sd_event_add_io(f->event, &f->stdout_event_source, STDOUT_FILENO, EPOLLOUT|EPOLLET, on_stdout_event, f); + if (r == -EPERM) + /* stdout without epoll support. Likely redirected to regular file. */ + f->stdout_writable = true; + else if (r < 0) + return r; + + r = sd_event_add_signal(f->event, &f->sigwinch_event_source, SIGWINCH, on_sigwinch_event, f); + + *ret = f; + f = NULL; + + return 0; +} + +PTYForward *pty_forward_free(PTYForward *f) { + + if (f) { + sd_event_source_unref(f->stdin_event_source); + sd_event_source_unref(f->stdout_event_source); + sd_event_source_unref(f->master_event_source); + sd_event_unref(f->event); + + if (f->saved_stdout) + tcsetattr(STDOUT_FILENO, TCSANOW, &f->saved_stdout_attr); + if (f->saved_stdin) + tcsetattr(STDIN_FILENO, TCSANOW, &f->saved_stdin_attr); + + free(f); + } /* STDIN/STDOUT should not be nonblocking normally, so let's * unconditionally reset it */ fd_nonblock(STDIN_FILENO, false); fd_nonblock(STDOUT_FILENO, false); - return r; - + return NULL; } diff --git a/src/shared/ptyfwd.h b/src/shared/ptyfwd.h index 8b657023a9..5a612fd597 100644 --- a/src/shared/ptyfwd.h +++ b/src/shared/ptyfwd.h @@ -24,4 +24,11 @@ #include <sys/types.h> #include <signal.h> -int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo); +#include "sd-event.h" + +typedef struct PTYForward PTYForward; + +int pty_forward_new(sd_event *event, int master, PTYForward **f); +PTYForward *pty_forward_free(PTYForward *f); + +DEFINE_TRIVIAL_CLEANUP_FUNC(PTYForward*, pty_forward_free); |