chiark / gitweb /
ptyforward: rework PTY forwarder logic used by nspawn to utilize the normal event...
[elogind.git] / src / nspawn / nspawn.c
index 5af89c9b3238560e064d51fff46795ddb2a8e4bd..e199eb665aaff63dcb986f7b0b846558d31a31bd 100644 (file)
@@ -89,6 +89,7 @@
 #include "copy.h"
 #include "base-filesystem.h"
 #include "barrier.h"
+#include "event-util.h"
 
 #ifdef HAVE_SECCOMP
 #include "seccomp-util.h"
@@ -675,7 +676,18 @@ static int mount_all(const char *dest) {
                 if (mount_table[k].what && t > 0)
                         continue;
 
-                mkdir_p(where, 0755);
+                t = mkdir_p(where, 0755);
+                if (t < 0) {
+                        if (mount_table[k].fatal) {
+                               log_error("Failed to create directory %s: %s", where, strerror(-t));
+
+                                if (r == 0)
+                                        r = t;
+                        } else
+                               log_warning("Failed to create directory %s: %s", where, strerror(-t));
+
+                        continue;
+                }
 
 #ifdef HAVE_SELINUX
                 if (arg_selinux_apifs_context &&
@@ -694,13 +706,15 @@ static int mount_all(const char *dest) {
                           where,
                           mount_table[k].type,
                           mount_table[k].flags,
-                          o) < 0 &&
-                    mount_table[k].fatal) {
+                          o) < 0) {
 
-                        log_error("mount(%s) failed: %m", where);
+                        if (mount_table[k].fatal) {
+                                log_error("mount(%s) failed: %m", where);
 
-                        if (r == 0)
-                                r = -errno;
+                                if (r == 0)
+                                        r = -errno;
+                        } else
+                                log_warning("mount(%s) failed: %m", where);
                 }
         }
 
@@ -743,15 +757,35 @@ static int mount_binds(const char *dest, char **l, bool ro) {
 
                 /* Create the mount point, but be conservative -- refuse to create block
                  * and char devices. */
-                if (S_ISDIR(source_st.st_mode))
-                        mkdir_label(where, 0755);
-                else if (S_ISFIFO(source_st.st_mode))
-                        mkfifo(where, 0644);
-                else if (S_ISSOCK(source_st.st_mode))
-                        mknod(where, 0644 | S_IFSOCK, 0);
-                else if (S_ISREG(source_st.st_mode))
-                        touch(where);
-                else {
+                if (S_ISDIR(source_st.st_mode)) {
+                        r = mkdir_label(where, 0755);
+                        if (r < 0 && errno != EEXIST) {
+                                log_error("Failed to create mount point %s: %s", where, strerror(-r));
+
+                                return r;
+                        }
+                } else if (S_ISFIFO(source_st.st_mode)) {
+                        r = mkfifo(where, 0644);
+                        if (r < 0 && errno != EEXIST) {
+                                log_error("Failed to create mount point %s: %m", where);
+
+                                return -errno;
+                        }
+                } else if (S_ISSOCK(source_st.st_mode)) {
+                        r = mknod(where, 0644 | S_IFSOCK, 0);
+                        if (r < 0 && errno != EEXIST) {
+                                log_error("Failed to create mount point %s: %m", where);
+
+                                return -errno;
+                        }
+                } else if (S_ISREG(source_st.st_mode)) {
+                        r = touch(where);
+                        if (r < 0) {
+                                log_error("Failed to create mount point %s: %s", where, strerror(-r));
+
+                                return r;
+                        }
+                } else {
                         log_error("Refusing to create mountpoint for file: %s", *x);
                         return -ENOTSUP;
                 }
@@ -778,12 +812,18 @@ static int mount_tmpfs(const char *dest) {
 
         STRV_FOREACH_PAIR(i, o, arg_tmpfs) {
                 _cleanup_free_ char *where = NULL;
+                int r;
 
                 where = strappend(dest, *i);
                 if (!where)
                         return log_oom();
 
-                mkdir_label(where, 0755);
+                r = mkdir_label(where, 0755);
+                if (r < 0) {
+                        log_error("creating mount point for tmpfs %s failed: %s", where, strerror(-r));
+
+                        return r;
+                }
 
                 if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, *o) < 0) {
                         log_error("tmpfs mount to %s failed: %m", where);
@@ -844,8 +884,19 @@ static int setup_timezone(const char *dest) {
         if (!what)
                 return log_oom();
 
-        mkdir_parents(where, 0755);
-        unlink(where);
+        r = mkdir_parents(where, 0755);
+        if (r < 0) {
+                log_error("Failed to create directory for timezone info %s in container: %s", where, strerror(-r));
+
+                return 0;
+        }
+
+        r = unlink(where);
+        if (r < 0 && errno != ENOENT) {
+                log_error("Failed to remove existing timezone info %s in container: %m", where);
+
+                return 0;
+        }
 
         if (symlink(what, where) < 0) {
                 log_error("Failed to correct timezone of container: %m");
@@ -857,6 +908,7 @@ static int setup_timezone(const char *dest) {
 
 static int setup_resolv_conf(const char *dest) {
         _cleanup_free_ char *where = NULL;
+        int r;
 
         assert(dest);
 
@@ -870,8 +922,19 @@ static int setup_resolv_conf(const char *dest) {
 
         /* We don't really care for the results of this really. If it
          * fails, it fails, but meh... */
-        mkdir_parents(where, 0755);
-        copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW, 0644);
+        r = mkdir_parents(where, 0755);
+        if (r < 0) {
+                log_warning("Failed to create parent directory for resolv.conf %s: %s", where, strerror(-r));
+
+                return 0;
+        }
+
+        r = copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW, 0644);
+        if (r < 0) {
+                log_warning("Failed to copy /etc/resolv.conf to %s: %s", where, strerror(-r));
+
+                return 0;
+        }
 
         return 0;
 }
@@ -895,7 +958,11 @@ static int setup_volatile_state(const char *directory) {
         }
 
         p = strappenda(directory, "/var");
-        mkdir(p, 0755);
+        r = mkdir(p, 0755);
+        if (r < 0 && errno != EEXIST) {
+                log_error("Failed to create %s: %m", directory);
+                return -errno;
+        }
 
         if (mount("tmpfs", p, "tmpfs", MS_STRICTATIME, "mode=755") < 0) {
                 log_error("Failed to mount tmpfs to /var: %m");
@@ -935,7 +1002,13 @@ static int setup_volatile(const char *directory) {
         f = strappenda(directory, "/usr");
         t = strappenda(template, "/usr");
 
-        mkdir(t, 0755);
+        r = mkdir(t, 0755);
+        if (r < 0 && errno != EEXIST) {
+                log_error("Failed to create %s: %m", t);
+                r = -errno;
+                goto fail;
+        }
+
         if (mount(f, t, "bind", MS_BIND|MS_REC, NULL) < 0) {
                 log_error("Failed to create /usr bind mount: %m");
                 r = -errno;
@@ -1029,7 +1102,8 @@ static int copy_devnodes(const char *dest) {
                 "full\0"
                 "random\0"
                 "urandom\0"
-                "tty\0";
+                "tty\0"
+                "net/tun\0";
 
         const char *d;
         int r = 0;
@@ -1060,10 +1134,17 @@ static int copy_devnodes(const char *dest) {
                         log_error("%s is not a char or block device, cannot copy", from);
                         return -EIO;
 
-                } else if (mknod(to, st.st_mode, st.st_rdev) < 0) {
+                } else {
+                        r = mkdir_parents(to, 0775);
+                        if (r < 0) {
+                                log_error("Failed to create parent directory of %s: %s", to, strerror(-r));
+                                return -r;
+                        }
 
-                        log_error("mknod(%s) failed: %m", dest);
-                        return  -errno;
+                        if (mknod(to, st.st_mode, st.st_rdev) < 0) {
+                                log_error("mknod(%s) failed: %m", dest);
+                                return  -errno;
+                        }
                 }
         }
 
@@ -1209,7 +1290,7 @@ static int setup_hostname(void) {
         if (arg_share_system)
                 return 0;
 
-        if (sethostname(arg_machine, strlen(arg_machine)) < 0)
+        if (sethostname_idempotent(arg_machine) < 0)
                 return -errno;
 
         return 0;
@@ -1294,7 +1375,7 @@ static int setup_journal(const char *directory) {
 
                         r = mkdir_p(q, 0755);
                         if (r < 0)
-                                log_warning("failed to create directory %s: %m", q);
+                                log_warning("Failed to create directory %s: %m", q);
                         return 0;
                 }
 
@@ -1329,7 +1410,7 @@ static int setup_journal(const char *directory) {
 
                 r = mkdir_p(q, 0755);
                 if (r < 0)
-                        log_warning("failed to create directory %s: %m", q);
+                        log_warning("Failed to create directory %s: %m", q);
                 return 0;
         }
 
@@ -1465,7 +1546,7 @@ static int register_machine(pid_t pid, int local_ifindex) {
                         return r;
                 }
 
-                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 10,
+                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 11,
                                           /* Allow the container to
                                            * access and create the API
                                            * device nodes, so that
@@ -1478,6 +1559,7 @@ static int register_machine(pid_t pid, int local_ifindex) {
                                           "/dev/random", "rwm",
                                           "/dev/urandom", "rwm",
                                           "/dev/tty", "rwm",
+                                          "/dev/net/tun", "rwm",
                                           /* Allow the container
                                            * access to ptys. However,
                                            * do not permit the
@@ -1657,7 +1739,7 @@ static int setup_veth(pid_t pid, char iface_name[IFNAMSIZ], int *ifi) {
 
         /* Use two different interface name prefixes depending whether
          * we are in bridge mode or not. */
-        snprintf(iface_name, IFNAMSIZ, "%s-%s",
+        snprintf(iface_name, IFNAMSIZ - 1, "%s-%s",
                  arg_network_bridge ? "vb" : "ve", arg_machine);
 
         r = generate_mac(&mac_container, CONTAINER_HASH_KEY);
@@ -2535,20 +2617,27 @@ static int mount_devices(
 
 static void loop_remove(int nr, int *image_fd) {
         _cleanup_close_ int control = -1;
+        int r;
 
         if (nr < 0)
                 return;
 
         if (image_fd && *image_fd >= 0) {
-                ioctl(*image_fd, LOOP_CLR_FD);
+                r = ioctl(*image_fd, LOOP_CLR_FD);
+                if (r < 0)
+                        log_warning("Failed to close loop image: %m");
                 *image_fd = safe_close(*image_fd);
         }
 
         control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
-        if (control < 0)
+        if (control < 0) {
+                log_warning("Failed to open /dev/loop-control: %m");
                 return;
+        }
 
-        ioctl(control, LOOP_CTL_REMOVE, nr);
+        r = ioctl(control, LOOP_CTL_REMOVE, nr);
+        if (r < 0)
+                log_warning("Failed to remove loop %d: %m", nr);
 }
 
 static int spawn_getent(const char *database, const char *key, pid_t *rpid) {
@@ -2823,8 +2912,8 @@ static int change_uid_gid(char **_home) {
  *       container argument.
  * > 0 : The program executed in the container terminated with an
  *       error.  The exit code of the program executed in the
- *       container is returned.  No change is made to the container
- *       argument.
+ *       container is returned.  The container argument has been set
+ *       to CONTAINER_TERMINATED.
  *   0 : The container is being rebooted, has been shut down or exited
  *       successfully.  The container argument has been set to either
  *       CONTAINER_TERMINATED or CONTAINER_REBOOTED.
@@ -2833,8 +2922,8 @@ static int change_uid_gid(char **_home) {
  * error is indicated by a non-zero value.
  */
 static int wait_for_container(pid_t pid, ContainerStatus *container) {
-        int r;
         siginfo_t status;
+        int r;
 
         r = wait_for_terminate(pid, &status);
         if (r < 0) {
@@ -2843,51 +2932,40 @@ static int wait_for_container(pid_t pid, ContainerStatus *container) {
         }
 
         switch (status.si_code) {
+
         case CLD_EXITED:
-                r = status.si_status;
-                if (r == 0) {
-                        if (!arg_quiet)
-                                log_debug("Container %s exited successfully.",
-                                          arg_machine);
+                if (status.si_status == 0) {
+                        log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s exited successfully.", arg_machine);
 
-                        *container = CONTAINER_TERMINATED;
-                } else {
-                        log_error("Container %s failed with error code %i.",
-                                  arg_machine, status.si_status);
-                }
-                break;
+                } else
+                        log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s failed with error code %i.", arg_machine, status.si_status);
+
+                *container = CONTAINER_TERMINATED;
+                return status.si_status;
 
         case CLD_KILLED:
                 if (status.si_status == SIGINT) {
-                        if (!arg_quiet)
-                                log_info("Container %s has been shut down.",
-                                         arg_machine);
 
+                        log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s has been shut down.", arg_machine);
                         *container = CONTAINER_TERMINATED;
-                        r = 0;
-                        break;
+                        return 0;
+
                 } else if (status.si_status == SIGHUP) {
-                        if (!arg_quiet)
-                                log_info("Container %s is being rebooted.",
-                                         arg_machine);
 
+                        log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s is being rebooted.", arg_machine);
                         *container = CONTAINER_REBOOTED;
-                        r = 0;
-                        break;
+                        return 0;
                 }
+
                 /* CLD_KILLED fallthrough */
 
         case CLD_DUMPED:
-                log_error("Container %s terminated by signal %s.",
-                          arg_machine, signal_to_string(status.si_status));
-                r = -1;
-                break;
+                log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status));
+                return -EIO;
 
         default:
-                log_error("Container %s failed due to unknown reason.",
-                          arg_machine);
-                r = -1;
-                break;
+                log_error("Container %s failed due to unknown reason.", arg_machine);
+                return -EIO;
         }
 
         return r;
@@ -2895,6 +2973,22 @@ static int wait_for_container(pid_t pid, ContainerStatus *container) {
 
 static void nop_handler(int sig) {}
 
+static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+        pid_t pid;
+
+        pid = PTR_TO_UINT32(userdata);
+        if (pid > 0) {
+                if (kill(pid, SIGRTMIN+3) >= 0) {
+                        log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
+                        sd_event_source_set_userdata(s, NULL);
+                        return 0;
+                }
+        }
+
+        sd_event_exit(sd_event_source_get_event(s), 0);
+        return 0;
+}
+
 int main(int argc, char *argv[]) {
 
         _cleanup_free_ char *kdbus_domain = NULL, *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL;
@@ -3076,11 +3170,12 @@ int main(int argc, char *argv[]) {
                   "STATUS=Container running.");
 
         assert_se(sigemptyset(&mask) == 0);
-        assert_se(sigemptyset(&mask_chld) == 0);
-        sigaddset(&mask_chld, SIGCHLD);
         sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1);
         assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0);
 
+        assert_se(sigemptyset(&mask_chld) == 0);
+        assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
+
         for (;;) {
                 ContainerStatus container_status;
                 _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
@@ -3417,6 +3512,8 @@ int main(int argc, char *argv[]) {
 
                 /* wait for child-setup to be done */
                 if (barrier_place_and_sync(&barrier)) {
+                        _cleanup_event_unref_ sd_event *event = NULL;
+                        _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
                         int ifi = 0;
 
                         r = move_network_interfaces(pid);
@@ -3455,12 +3552,39 @@ int main(int argc, char *argv[]) {
                          * control to the code to run inside the container. */
                         barrier_place(&barrier);
 
-                        k = process_pty(master, &mask, arg_boot ? pid : 0, SIGRTMIN+3);
-                        if (k < 0) {
-                                r = EXIT_FAILURE;
-                                break;
+                        r = sd_event_new(&event);
+                        if (r < 0) {
+                                log_error("Failed to get default event source: %s", strerror(-r));
+                                goto finish;
                         }
 
+                        if (arg_boot) {
+                                /* Try to kill the init system on SIGINT or SIGTERM */
+                                sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, UINT32_TO_PTR(pid));
+                                sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, UINT32_TO_PTR(pid));
+                        } else {
+                                /* Immediately exit */
+                                sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+                                sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
+                        }
+
+                        /* simply exit on sigchld */
+                        sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
+
+                        r = pty_forward_new(event, master, &forward);
+                        if (r < 0) {
+                                log_error("Failed to create PTY forwarder: %s", strerror(-r));
+                                goto finish;
+                        }
+
+                        r = sd_event_loop(event);
+                        if (r < 0) {
+                                log_error("Failed to run event loop: %s", strerror(-r));
+                                return r;
+                        }
+
+                        forward = pty_forward_free(forward);
+
                         if (!arg_quiet)
                                 putc('\n', stdout);