From f1b1f3bab4764964d12a62aba1cdbd71ec6415ae Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 30 Oct 2013 18:58:59 +0100 Subject: [PATCH] nspawn: split out pty forwaring logic into ptyfwd.c Conflicts: Makefile.am src/nspawn/nspawn.c --- Makefile.am | 4 +- src/nspawn/nspawn.c | 245 +------------------------------------------------- src/shared/ptyfwd.c | 252 ++++++++++++++++++++++++++++++++++++++++++++++++++++ src/shared/ptyfwd.h | 27 ++++++ 4 files changed, 284 insertions(+), 244 deletions(-) create mode 100644 src/shared/ptyfwd.c create mode 100644 src/shared/ptyfwd.h diff --git a/Makefile.am b/Makefile.am index 34de7f2..b4fc33b 100644 --- a/Makefile.am +++ b/Makefile.am @@ -724,7 +724,9 @@ libsystemd_shared_la_SOURCES = \ src/shared/boot-timestamps.c \ src/shared/refcnt.h \ src/shared/mkdir.c \ - src/shared/mkdir.h + src/shared/mkdir.h \ + src/shared/ptyfwd.c \ + src/shared/ptyfwd.h #------------------------------------------------------------------------------- noinst_LTLIBRARIES += \ diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index db47fbd..cda6c82 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -63,6 +63,7 @@ #include "fileio.h" #include "bus-internal.h" #include "bus-message.h" +#include "ptyfwd.h" #ifndef TTY_GID #define TTY_GID 5 @@ -937,248 +938,6 @@ static int drop_capabilities(void) { return capability_bounding_set_drop(~arg_retain, false); } -static int process_pty(int master, pid_t pid, sigset_t *mask) { - - 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; - int ep = -1, signal_fd = -1, r; - bool tried_orderly_shutdown = false; - - assert(master >= 0); - assert(pid > 0); - assert(mask); - - fd_nonblock(STDIN_FILENO, 1); - fd_nonblock(STDOUT_FILENO, 1); - fd_nonblock(master, 1); - - signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC); - if (signal_fd < 0) { - log_error("signalfd(): %m"); - r = -errno; - goto finish; - } - - ep = epoll_create1(EPOLL_CLOEXEC); - if (ep < 0) { - log_error("Failed to create epoll: %m"); - r = -errno; - goto finish; - } - - /* 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; - - if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0) { - log_error("Failed to register STDIN in epoll: %m"); - r = -errno; - goto finish; - } - } - - zero(stdout_ev); - stdout_ev.events = EPOLLOUT|EPOLLET; - stdout_ev.data.fd = STDOUT_FILENO; - - zero(master_ev); - master_ev.events = EPOLLIN|EPOLLOUT|EPOLLET; - master_ev.data.fd = master; - - zero(signal_ev); - signal_ev.events = EPOLLIN; - signal_ev.data.fd = signal_fd; - - if (epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0) { - if (errno != EPERM) { - log_error("Failed to register stdout in epoll: %m"); - r = -errno; - goto finish; - } - /* 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"); - r = -errno; - goto finish; - } - - for (;;) { - struct epoll_event ev[16]; - ssize_t k; - int i, nfds; - - nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1); - if (nfds < 0) { - - if (errno == EINTR || errno == EAGAIN) - continue; - - log_error("epoll_wait(): %m"); - r = -errno; - goto finish; - } - - assert(nfds >= 1); - - 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; - - } else if (ev[i].data.fd == master) { - - if (ev[i].events & (EPOLLIN|EPOLLHUP)) - master_readable = true; - - if (ev[i].events & (EPOLLOUT|EPOLLHUP)) - master_writable = true; - - } else if (ev[i].data.fd == signal_fd) { - struct signalfd_siginfo sfsi; - ssize_t n; - - n = read(signal_fd, &sfsi, sizeof(sfsi)); - if (n != sizeof(sfsi)) { - - if (n >= 0) { - log_error("Failed to read from signalfd: invalid block size"); - r = -EIO; - goto finish; - } - - if (errno != EINTR && errno != EAGAIN) { - log_error("Failed to read from signalfd: %m"); - r = -errno; - goto finish; - } - } else { - - if (sfsi.ssi_signo == SIGWINCH) { - struct winsize ws; - - /* The window size changed, let's forward that. */ - if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0) - ioctl(master, TIOCSWINSZ, &ws); - } else if (sfsi.ssi_signo == SIGTERM && arg_boot && !tried_orderly_shutdown) { - - log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination."); - - /* This only works for systemd... */ - tried_orderly_shutdown = true; - kill(pid, SIGRTMIN+3); - - } else { - r = 0; - goto finish; - } - } - } - } - - 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 || errno == EPIPE || errno == ECONNRESET || errno == EIO) - stdin_readable = false; - else { - log_error("read(): %m"); - r = -errno; - goto finish; - } - } else - in_buffer_full += (size_t) k; - } - - if (master_writable && in_buffer_full > 0) { - - k = write(master, in_buffer, in_buffer_full); - if (k < 0) { - - if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) - master_writable = false; - else { - log_error("write(): %m"); - r = -errno; - goto finish; - } - - } else { - assert(in_buffer_full >= (size_t) k); - memmove(in_buffer, in_buffer + k, in_buffer_full - k); - in_buffer_full -= k; - } - } - - if (master_readable && out_buffer_full < LINE_MAX) { - - k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full); - if (k < 0) { - - if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) - master_readable = false; - else { - log_error("read(): %m"); - r = -errno; - goto finish; - } - } else - out_buffer_full += (size_t) k; - } - - if (stdout_writable && out_buffer_full > 0) { - - k = write(STDOUT_FILENO, out_buffer, out_buffer_full); - if (k < 0) { - - if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) - stdout_writable = false; - else { - log_error("write(): %m"); - r = -errno; - goto finish; - } - - } else { - assert(out_buffer_full >= (size_t) k); - memmove(out_buffer, out_buffer + k, out_buffer_full - k); - out_buffer_full -= k; - } - } - } - } - -finish: - if (ep >= 0) - close_nointr_nofail(ep); - - if (signal_fd >= 0) - close_nointr_nofail(signal_fd); - - return r; -} - static int register_machine(void) { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; _cleanup_bus_unref_ sd_bus *bus = NULL; @@ -1683,7 +1442,7 @@ int main(int argc, char *argv[]) { fdset_free(fds); fds = NULL; - if (process_pty(master, pid, &mask) < 0) + if (process_pty(master, &mask, arg_boot ? pid : 0, SIGRTMIN+3) < 0) goto finish; if (saved_attr_valid) diff --git a/src/shared/ptyfwd.c b/src/shared/ptyfwd.c new file mode 100644 index 0000000..1e2852b --- /dev/null +++ b/src/shared/ptyfwd.c @@ -0,0 +1,252 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010-2013 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include +#include +#include +#include + +#include "util.h" +#include "ptyfwd.h" + +int process_pty(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 tried_orderly_shutdown = false; + _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, 1); + fd_nonblock(STDOUT_FILENO, 1); + fd_nonblock(master, 1); + + 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; + } + + /* 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; + + if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0) { + log_error("Failed to register STDIN in epoll: %m"); + return -errno; + } + } + + zero(stdout_ev); + stdout_ev.events = EPOLLOUT|EPOLLET; + stdout_ev.data.fd = STDOUT_FILENO; + + zero(master_ev); + master_ev.events = EPOLLIN|EPOLLOUT|EPOLLET; + master_ev.data.fd = master; + + zero(signal_ev); + signal_ev.events = EPOLLIN; + signal_ev.data.fd = signal_fd; + + 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; + } + + /* 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; + + nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1); + if (nfds < 0) { + + if (errno == EINTR || errno == EAGAIN) + continue; + + log_error("epoll_wait(): %m"); + return -errno; + } + + assert(nfds >= 1); + + 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; + + } else if (ev[i].data.fd == master) { + + if (ev[i].events & (EPOLLIN|EPOLLHUP)) + master_readable = true; + + if (ev[i].events & (EPOLLOUT|EPOLLHUP)) + master_writable = true; + + } else if (ev[i].data.fd == signal_fd) { + struct signalfd_siginfo sfsi; + ssize_t n; + + n = read(signal_fd, &sfsi, sizeof(sfsi)); + if (n != sizeof(sfsi)) { + + if (n >= 0) { + log_error("Failed to read from signalfd: invalid block size"); + return -EIO; + } + + if (errno != EINTR && errno != EAGAIN) { + log_error("Failed to read from signalfd: %m"); + return -errno; + } + } else { + + if (sfsi.ssi_signo == SIGWINCH) { + struct winsize ws; + + /* The window size changed, let's forward that. */ + if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0) + ioctl(master, TIOCSWINSZ, &ws); + + } else if (sfsi.ssi_signo == SIGTERM && kill_pid > 0 && signo > 0 && !tried_orderly_shutdown) { + + if (kill(kill_pid, signo) < 0) + return 0; + + log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination."); + + /* This only works for systemd... */ + tried_orderly_shutdown = true; + + } else + return 0; + } + } + } + + 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 || errno == EPIPE || errno == ECONNRESET || errno == EIO) + stdin_readable = false; + else { + log_error("read(): %m"); + return -errno; + } + } else + in_buffer_full += (size_t) k; + } + + if (master_writable && in_buffer_full > 0) { + + k = write(master, in_buffer, in_buffer_full); + if (k < 0) { + + if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) + master_writable = false; + else { + log_error("write(): %m"); + return -errno; + } + + } else { + assert(in_buffer_full >= (size_t) k); + memmove(in_buffer, in_buffer + k, in_buffer_full - k); + in_buffer_full -= k; + } + } + + if (master_readable && out_buffer_full < LINE_MAX) { + + k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full); + if (k < 0) { + + if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) + master_readable = false; + else { + log_error("read(): %m"); + return -errno; + } + } else + out_buffer_full += (size_t) k; + } + + if (stdout_writable && out_buffer_full > 0) { + + k = write(STDOUT_FILENO, out_buffer, out_buffer_full); + if (k < 0) { + + if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) + stdout_writable = false; + else { + log_error("write(): %m"); + return -errno; + } + + } else { + assert(out_buffer_full >= (size_t) k); + memmove(out_buffer, out_buffer + k, out_buffer_full - k); + out_buffer_full -= k; + } + } + } + } +} diff --git a/src/shared/ptyfwd.h b/src/shared/ptyfwd.h new file mode 100644 index 0000000..8b65702 --- /dev/null +++ b/src/shared/ptyfwd.h @@ -0,0 +1,27 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +#pragma once + +/*** + This file is part of systemd. + + Copyright 2010-2013 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include + +int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo);