summaryrefslogtreecommitdiff
path: root/src/shared/ptyfwd.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/shared/ptyfwd.c')
-rw-r--r--src/shared/ptyfwd.c222
1 files changed, 170 insertions, 52 deletions
diff --git a/src/shared/ptyfwd.c b/src/shared/ptyfwd.c
index 1e2852b1af..7225b933ff 100644
--- a/src/shared/ptyfwd.c
+++ b/src/shared/ptyfwd.c
@@ -28,12 +28,49 @@
#include "util.h"
#include "ptyfwd.h"
-int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
+#define ESCAPE_USEC USEC_PER_SEC
+
+static bool look_for_escape(usec_t *timestamp, unsigned *counter, const char *buffer, size_t n) {
+ const char *p;
+
+ assert(timestamp);
+ assert(counter);
+ assert(buffer);
+ assert(n > 0);
+
+ for (p = buffer; p < buffer + n; p++) {
+
+ /* Check for ^] */
+ if (*p == 0x1D) {
+ usec_t nw = now(CLOCK_MONOTONIC);
+
+ if (*counter == 0 || nw > *timestamp + USEC_PER_SEC) {
+ *timestamp = nw;
+ *counter = 1;
+ } else {
+ (*counter)++;
+
+ if (*counter >= 3)
+ return true;
+ }
+ } else {
+ *timestamp = 0;
+ *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 tried_orderly_shutdown = 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);
@@ -103,7 +140,7 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
ssize_t k;
int i, nfds;
- nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1);
+ nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), quit ? 0 : -1);
if (nfds < 0) {
if (errno == EINTR || errno == EAGAIN)
@@ -113,7 +150,8 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
return -errno;
}
- assert(nfds >= 1);
+ if (nfds == 0)
+ return 0;
for (i = 0; i < nfds; i++) {
if (ev[i].data.fd == STDIN_FILENO) {
@@ -134,45 +172,8 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
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;
- }
- }
+ } else if (ev[i].data.fd == signal_fd)
+ process_signalfd = true;
}
while ((stdin_readable && in_buffer_full <= 0) ||
@@ -185,14 +186,26 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
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)
+ if (errno == EAGAIN)
stdin_readable = false;
- else {
+ 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;
}
- } else
+ } 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;
+ }
}
if (master_writable && in_buffer_full > 0) {
@@ -200,9 +213,13 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
k = write(master, in_buffer, in_buffer_full);
if (k < 0) {
- if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
+ if (errno == EAGAIN || errno == EIO)
master_writable = false;
- else {
+ 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;
}
@@ -219,9 +236,21 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
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)
+ /* 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 {
+ 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;
}
@@ -234,9 +263,13 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
k = write(STDOUT_FILENO, out_buffer, out_buffer_full);
if (k < 0) {
- if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
+ if (errno == EAGAIN)
stdout_writable = false;
- else {
+ 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;
}
@@ -247,6 +280,91 @@ int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
out_buffer_full -= k;
}
}
+
+ }
+
+ if (process_signalfd) {
+ 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)
+ quit = true;
+ else {
+ log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
+
+ /* This only works for systemd... */
+ tried_orderly_shutdown = true;
+ }
+
+ } else
+ /* Signals that where
+ * delivered via signalfd that
+ * we didn't know are a reason
+ * for us to quit */
+ quit = true;
+ }
+ }
+
+ 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. */
+
+ if ((out_buffer_full <= 0 || stdout_hangup) &&
+ (in_buffer_full <= 0 || master_hangup))
+ return !quit;
}
}
}
+
+int process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
+ struct termios saved_attr;
+ bool saved = false;
+ struct winsize ws;
+ int r;
+
+ if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
+ ioctl(master, TIOCSWINSZ, &ws);
+
+ if (tcgetattr(STDIN_FILENO, &saved_attr) >= 0) {
+ struct termios raw_attr;
+ saved = true;
+
+ raw_attr = saved_attr;
+ cfmakeraw(&raw_attr);
+ raw_attr.c_lflag &= ~ECHO;
+
+ tcsetattr(STDIN_FILENO, TCSANOW, &raw_attr);
+ }
+
+ r = process_pty_loop(master, mask, kill_pid, signo);
+
+ if (saved)
+ tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
+
+ return r;
+
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-07 08:37:07 +0000