X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=04396ebed11716053e96a936d4d2678422ef503a;hp=0466ddbff3ebae0f1b0569da607f8adbf93d27e9;hb=f01ae8260d90ccff2f299242cd370ab58ea723f0;hpb=2822da4fb7f891e5320f02f1d00f64b72221ced4 diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 0466ddbff..04396ebed 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -31,7 +31,6 @@ #include #include #include -#include #include #include #include @@ -90,7 +89,9 @@ #include "base-filesystem.h" #include "barrier.h" #include "event-util.h" +#include "capability.h" #include "cap-list.h" +#include "btrfs-util.h" #ifdef HAVE_SECCOMP #include "seccomp-util.h" @@ -115,6 +116,7 @@ typedef enum Volatile { } Volatile; static char *arg_directory = NULL; +static char *arg_template = NULL; static char *arg_user = NULL; static sd_id128_t arg_uuid = {}; static char *arg_machine = NULL; @@ -124,6 +126,7 @@ static const char *arg_slice = NULL; static bool arg_private_network = false; static bool arg_read_only = false; static bool arg_boot = false; +static bool arg_ephemeral = false; static LinkJournal arg_link_journal = LINK_AUTO; static bool arg_link_journal_try = false; static uint64_t arg_retain = @@ -166,7 +169,7 @@ static char **arg_network_macvlan = NULL; static bool arg_network_veth = false; static const char *arg_network_bridge = NULL; static unsigned long arg_personality = 0xffffffffLU; -static const char *arg_image = NULL; +static char *arg_image = NULL; static Volatile arg_volatile = VOLATILE_NO; static void help(void) { @@ -176,7 +179,11 @@ static void help(void) { " --version Print version string\n" " -q --quiet Do not show status information\n" " -D --directory=PATH Root directory for the container\n" - " -i --image=PATH File system device or image for the container\n" + " --template=PATH Initialize root directory from template directory,\n" + " if missing\n" + " -x --ephemeral Run container with snapshot of root directory, and\n" + " remove it after exit\n" + " -i --image=PATH File system device or disk image for the container\n" " -b --boot Boot up full system (i.e. invoke init)\n" " -u --user=USER Run the command under specified user or uid\n" " -M --machine=NAME Set the machine name for the container\n" @@ -221,6 +228,27 @@ static void help(void) { program_invocation_short_name); } +static int set_sanitized_path(char **b, const char *path) { + char *p; + + assert(b); + assert(path); + + p = canonicalize_file_name(path); + if (!p) { + if (errno != ENOENT) + return -errno; + + p = path_make_absolute_cwd(path); + if (!p) + return -ENOMEM; + } + + free(*b); + *b = path_kill_slashes(p); + return 0; +} + static int parse_argv(int argc, char *argv[]) { enum { @@ -244,12 +272,15 @@ static int parse_argv(int argc, char *argv[]) { ARG_NETWORK_BRIDGE, ARG_PERSONALITY, ARG_VOLATILE, + ARG_TEMPLATE, }; static const struct option options[] = { { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, ARG_VERSION }, { "directory", required_argument, NULL, 'D' }, + { "template", required_argument, NULL, ARG_TEMPLATE }, + { "ephemeral", no_argument, NULL, 'x' }, { "user", required_argument, NULL, 'u' }, { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK }, { "boot", no_argument, NULL, 'b' }, @@ -286,7 +317,7 @@ static int parse_argv(int argc, char *argv[]) { assert(argc >= 0); assert(argv); - while ((c = getopt_long(argc, argv, "+hD:u:bL:M:jS:Z:qi:", options, NULL)) >= 0) + while ((c = getopt_long(argc, argv, "+hD:u:bL:M:jS:Z:qi:x", options, NULL)) >= 0) switch (c) { @@ -300,17 +331,28 @@ static int parse_argv(int argc, char *argv[]) { return 0; case 'D': - free(arg_directory); - arg_directory = canonicalize_file_name(optarg); - if (!arg_directory) { - log_error_errno(errno, "Invalid root directory: %m"); - return -ENOMEM; - } + r = set_sanitized_path(&arg_directory, optarg); + if (r < 0) + return log_error_errno(r, "Invalid root directory: %m"); + + break; + + case ARG_TEMPLATE: + r = set_sanitized_path(&arg_template, optarg); + if (r < 0) + return log_error_errno(r, "Invalid template directory: %m"); break; case 'i': - arg_image = optarg; + r = set_sanitized_path(&arg_image, optarg); + if (r < 0) + return log_error_errno(r, "Invalid image path: %m"); + + break; + + case 'x': + arg_ephemeral = true; break; case 'u': @@ -369,15 +411,13 @@ static int parse_argv(int argc, char *argv[]) { free(arg_machine); arg_machine = NULL; } else { - - if (!hostname_is_valid(optarg)) { + if (!machine_name_is_valid(optarg)) { log_error("Invalid machine name: %s", optarg); return -EINVAL; } - free(arg_machine); - arg_machine = strdup(optarg); - if (!arg_machine) + r = free_and_strdup(&arg_machine, optarg); + if (r < 0) return log_oom(); break; @@ -437,15 +477,19 @@ static int parse_argv(int argc, char *argv[]) { break; case ARG_LINK_JOURNAL: - if (streq(optarg, "auto")) + if (streq(optarg, "auto")) { arg_link_journal = LINK_AUTO; - else if (streq(optarg, "no")) + arg_link_journal_try = false; + } else if (streq(optarg, "no")) { arg_link_journal = LINK_NO; - else if (streq(optarg, "guest")) + arg_link_journal_try = false; + } else if (streq(optarg, "guest")) { arg_link_journal = LINK_GUEST; - else if (streq(optarg, "host")) + arg_link_journal_try = false; + } else if (streq(optarg, "host")) { arg_link_journal = LINK_HOST; - else if (streq(optarg, "try-guest")) { + arg_link_journal_try = false; + } else if (streq(optarg, "try-guest")) { arg_link_journal = LINK_GUEST; arg_link_journal_try = true; } else if (streq(optarg, "try-host")) { @@ -623,6 +667,31 @@ static int parse_argv(int argc, char *argv[]) { return -EINVAL; } + if (arg_template && arg_image) { + log_error("--template= and --image= may not be combined."); + return -EINVAL; + } + + if (arg_template && !(arg_directory || arg_machine)) { + log_error("--template= needs --directory= or --machine=."); + return -EINVAL; + } + + if (arg_ephemeral && arg_template) { + log_error("--ephemeral and --template= may not be combined."); + return -EINVAL; + } + + if (arg_ephemeral && arg_image) { + log_error("--ephemeral and --image= may not be combined."); + return -EINVAL; + } + + if (arg_ephemeral && !IN_SET(arg_link_journal, LINK_NO, LINK_AUTO)) { + log_error("--ephemeral and --link-journal= may not be combined."); + return -EINVAL; + } + if (arg_volatile != VOLATILE_NO && arg_read_only) { log_error("Cannot combine --read-only with --volatile. Note that --volatile already implies a read-only base hierarchy."); return -EINVAL; @@ -1253,6 +1322,10 @@ static int setup_journal(const char *directory) { char *id; int r; + /* Don't link journals in ephemeral mode */ + if (arg_ephemeral) + return 0; + p = strappend(directory, "/etc/machine-id"); if (!p) return log_oom(); @@ -1281,8 +1354,7 @@ static int setup_journal(const char *directory) { "Host and machine ids are equal (%s): refusing to link journals", id); if (arg_link_journal == LINK_AUTO) return 0; - return - -EEXIST; + return -EEXIST; } if (arg_link_journal == LINK_NO) @@ -2010,6 +2082,27 @@ finish: } +static int setup_propagate(const char *root) { + const char *p, *q; + + (void) mkdir_p("/run/systemd/nspawn/", 0755); + (void) mkdir_p("/run/systemd/nspawn/propagate", 0600); + p = strappenda("/run/systemd/nspawn/propagate/", arg_machine); + (void) mkdir_p(p, 0600); + + q = strappenda(root, "/run/systemd/nspawn/incoming"); + mkdir_parents(q, 0755); + mkdir_p(q, 0600); + + if (mount(p, q, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Failed to install propagation bind mount."); + + if (mount(NULL, q, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) + return log_error_errno(errno, "Failed to make propagation mount read-only"); + + return 0; +} + static int setup_image(char **device_path, int *loop_nr) { struct loop_info64 info = { .lo_flags = LO_FLAGS_AUTOCLEAR|LO_FLAGS_PARTSCAN @@ -2021,6 +2114,7 @@ static int setup_image(char **device_path, int *loop_nr) { assert(device_path); assert(loop_nr); + assert(arg_image); fd = open(arg_image, O_CLOEXEC|(arg_read_only ? O_RDONLY : O_RDWR)|O_NONBLOCK|O_NOCTTY); if (fd < 0) @@ -2119,6 +2213,7 @@ static int dissect_image( assert(home_device); assert(srv_device); assert(secondary); + assert(arg_image); b = blkid_new_probe(); if (!b) @@ -2786,78 +2881,97 @@ static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo return 0; } +static int determine_names(void) { + + if (!arg_image && !arg_directory) { + if (arg_machine) + arg_directory = strappend("/var/lib/container/", arg_machine); + else + arg_directory = get_current_dir_name(); + + if (!arg_directory) { + log_error("Failed to determine path, please use -D."); + return -EINVAL; + } + } + + if (!arg_machine) { + if (arg_directory && path_equal(arg_directory, "/")) + arg_machine = gethostname_malloc(); + else + arg_machine = strdup(basename(arg_image ?: arg_directory)); + + if (!arg_machine) + return log_oom(); + + hostname_cleanup(arg_machine, false); + if (!machine_name_is_valid(arg_machine)) { + log_error("Failed to determine machine name automatically, please use -M."); + return -EINVAL; + } + + if (arg_ephemeral) { + char *b; + + /* Add a random suffix when this is an + * ephemeral machine, so that we can run many + * instances at once without manually having + * to specify -M each time. */ + + if (asprintf(&b, "%s-%016" PRIx64, arg_machine, random_u64()) < 0) + return log_oom(); + + free(arg_machine); + arg_machine = b; + } + } + + return 0; +} + int main(int argc, char *argv[]) { - _cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL; + _cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL, *console = NULL; bool root_device_rw = true, home_device_rw = true, srv_device_rw = true; _cleanup_close_ int master = -1, image_fd = -1; _cleanup_close_pair_ int kmsg_socket_pair[2] = { -1, -1 }; _cleanup_fdset_free_ FDSet *fds = NULL; - int r = EXIT_FAILURE, k, n_fd_passed, loop_nr = -1; - const char *console = NULL; + int r, n_fd_passed, loop_nr = -1; char veth_name[IFNAMSIZ]; - bool secondary = false; + bool secondary = false, remove_subvol = false; sigset_t mask, mask_chld; pid_t pid = 0; + int ret = EXIT_SUCCESS; log_parse_environment(); log_open(); - k = parse_argv(argc, argv); - if (k < 0) - goto finish; - else if (k == 0) { - r = EXIT_SUCCESS; + r = parse_argv(argc, argv); + if (r <= 0) goto finish; - } - - if (!arg_image) { - if (arg_directory) { - char *p; - - p = path_make_absolute_cwd(arg_directory); - free(arg_directory); - arg_directory = p; - } else - arg_directory = get_current_dir_name(); - - if (!arg_directory) { - log_error("Failed to determine path, please use -D."); - goto finish; - } - path_kill_slashes(arg_directory); - } - - if (!arg_machine) { - arg_machine = strdup(basename(arg_image ? arg_image : arg_directory)); - if (!arg_machine) { - log_oom(); - goto finish; - } - hostname_cleanup(arg_machine, false); - if (isempty(arg_machine)) { - log_error("Failed to determine machine name automatically, please use -M."); - goto finish; - } - } + r = determine_names(); + if (r < 0) + goto finish; if (geteuid() != 0) { log_error("Need to be root."); + r = -EPERM; goto finish; } if (sd_booted() <= 0) { log_error("Not running on a systemd system."); + r = -EINVAL; goto finish; } log_close(); n_fd_passed = sd_listen_fds(false); if (n_fd_passed > 0) { - k = fdset_new_listen_fds(&fds, false); - if (k < 0) { - log_error_errno(k, "Failed to collect file descriptors: %m"); + r = fdset_new_listen_fds(&fds, false); + if (r < 0) { + log_error_errno(r, "Failed to collect file descriptors: %m"); goto finish; } } @@ -2865,14 +2979,67 @@ int main(int argc, char *argv[]) { log_open(); if (arg_directory) { - if (path_equal(arg_directory, "/")) { - log_error("Spawning container on root directory not supported."); + assert(!arg_image); + + if (path_equal(arg_directory, "/") && !arg_ephemeral) { + log_error("Spawning container on root directory is not supported. Consider using --ephemeral."); + r = -EINVAL; goto finish; } + if (arg_template) { + r = btrfs_subvol_snapshot(arg_template, arg_directory, arg_read_only, true); + if (r == -EEXIST) { + if (!arg_quiet) + log_info("Directory %s already exists, not populating from template %s.", arg_directory, arg_template); + } else if (r < 0) { + log_error_errno(r, "Couldn't create snapshort %s from %s: %m", arg_directory, arg_template); + goto finish; + } else { + if (!arg_quiet) + log_info("Populated %s from template %s.", arg_directory, arg_template); + } + + } else if (arg_ephemeral) { + char *np; + + /* If the specified path is a mount point we + * generate the new snapshot immediately + * inside it under a random name. However if + * the specified is not a mount point we + * create the new snapshot in the parent + * directory, just next to it. */ + r = path_is_mount_point(arg_directory, false); + if (r < 0) { + log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory); + goto finish; + } + if (r > 0) + r = tempfn_random_child(arg_directory, &np); + else + r = tempfn_random(arg_directory, &np); + if (r < 0) { + log_error_errno(r, "Failed to generate name for snapshot: %m"); + goto finish; + } + + r = btrfs_subvol_snapshot(arg_directory, np, arg_read_only, true); + if (r < 0) { + free(np); + log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory); + goto finish; + } + + free(arg_directory); + arg_directory = np; + + remove_subvol = true; + } + if (arg_boot) { if (path_is_os_tree(arg_directory) <= 0) { log_error("Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", arg_directory); + r = -EINVAL; goto finish; } } else { @@ -2882,13 +3049,17 @@ int main(int argc, char *argv[]) { argc > optind && path_is_absolute(argv[optind]) ? argv[optind] : "/usr/bin/"); if (access(p, F_OK) < 0) { log_error("Directory %s lacks the binary to execute or doesn't look like a binary tree. Refusing.", arg_directory); + r = -EINVAL; goto finish; - } } + } else { char template[] = "/tmp/nspawn-root-XXXXXX"; + assert(arg_image); + assert(!arg_template); + if (!mkdtemp(template)) { log_error_errno(errno, "Failed to create temporary directory: %m"); r = -errno; @@ -2918,27 +3089,27 @@ int main(int argc, char *argv[]) { master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); if (master < 0) { - log_error_errno(errno, "Failed to acquire pseudo tty: %m"); + r = log_error_errno(errno, "Failed to acquire pseudo tty: %m"); goto finish; } - console = ptsname(master); - if (!console) { - log_error_errno(errno, "Failed to determine tty name: %m"); + r = ptsname_malloc(master, &console); + if (r < 0) { + r = log_error_errno(r, "Failed to determine tty name: %m"); goto finish; } if (!arg_quiet) log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.", - arg_machine, arg_image ? arg_image : arg_directory); + arg_machine, arg_image ?: arg_directory); if (unlockpt(master) < 0) { - log_error_errno(errno, "Failed to unlock tty: %m"); + r = log_error_errno(errno, "Failed to unlock tty: %m"); goto finish; } if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) { - log_error_errno(errno, "Failed to create kmsg socket pair: %m"); + r = log_error_errno(errno, "Failed to create kmsg socket pair: %m"); goto finish; } @@ -2972,26 +3143,25 @@ int main(int argc, char *argv[]) { * give it a chance to call wait() and terminate. */ r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL); if (r < 0) { - log_error_errno(errno, "Failed to change the signal mask: %m"); + r = log_error_errno(errno, "Failed to change the signal mask: %m"); goto finish; } r = sigaction(SIGCHLD, &sa, NULL); if (r < 0) { - log_error_errno(errno, "Failed to install SIGCHLD handler: %m"); + r = log_error_errno(errno, "Failed to install SIGCHLD handler: %m"); goto finish; } - pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWNS| - (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)| - (arg_private_network ? CLONE_NEWNET : 0), NULL); + pid = raw_clone(SIGCHLD|CLONE_NEWNS| + (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)| + (arg_private_network ? CLONE_NEWNET : 0), NULL); if (pid < 0) { if (errno == EINVAL) - log_error_errno(errno, "clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m"); + r = log_error_errno(errno, "clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m"); else - log_error_errno(errno, "clone() failed: %m"); + r = log_error_errno(errno, "clone() failed: %m"); - r = pid; goto finish; } @@ -3030,14 +3200,14 @@ int main(int argc, char *argv[]) { reset_all_signal_handlers(); reset_signal_mask(); - k = open_terminal(console, O_RDWR); - if (k != STDIN_FILENO) { - if (k >= 0) { - safe_close(k); - k = -EINVAL; + r = open_terminal(console, O_RDWR); + if (r != STDIN_FILENO) { + if (r >= 0) { + safe_close(r); + r = -EINVAL; } - log_error_errno(k, "Failed to open console: %m"); + log_error_errno(r, "Failed to open console: %m"); _exit(EXIT_FAILURE); } @@ -3092,9 +3262,9 @@ int main(int argc, char *argv[]) { _exit(EXIT_FAILURE); if (arg_read_only) { - k = bind_remount_recursive(arg_directory, true); - if (k < 0) { - log_error_errno(k, "Failed to make tree read-only: %m"); + r = bind_remount_recursive(arg_directory, true); + if (r < 0) { + log_error_errno(r, "Failed to make tree read-only: %m"); _exit(EXIT_FAILURE); } } @@ -3110,6 +3280,9 @@ int main(int argc, char *argv[]) { dev_setup(arg_directory); + if (setup_propagate(arg_directory) < 0) + _exit(EXIT_FAILURE); + if (setup_seccomp() < 0) _exit(EXIT_FAILURE); @@ -3198,9 +3371,9 @@ int main(int argc, char *argv[]) { } if (fdset_size(fds) > 0) { - k = fdset_cloexec(fds, false); - if (k < 0) { - log_error("Failed to unset O_CLOEXEC for file descriptors."); + r = fdset_cloexec(fds, false); + if (r < 0) { + log_error_errno(r, "Failed to unset O_CLOEXEC for file descriptors."); _exit(EXIT_FAILURE); } @@ -3288,6 +3461,7 @@ int main(int argc, char *argv[]) { if (barrier_place_and_sync(&barrier)) { _cleanup_event_unref_ sd_event *event = NULL; _cleanup_(pty_forward_freep) PTYForward *forward = NULL; + char last_char = 0; int ifi = 0; r = move_network_interfaces(pid); @@ -3345,19 +3519,23 @@ int main(int argc, char *argv[]) { /* simply exit on sigchld */ sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL); - r = pty_forward_new(event, master, &forward); + r = pty_forward_new(event, master, true, &forward); if (r < 0) { log_error_errno(r, "Failed to create PTY forwarder: %m"); goto finish; } r = sd_event_loop(event); - if (r < 0) - return log_error_errno(r, "Failed to run event loop: %m"); + if (r < 0) { + log_error_errno(r, "Failed to run event loop: %m"); + goto finish; + } + + pty_forward_last_char(forward, &last_char); forward = pty_forward_free(forward); - if (!arg_quiet) + if (!arg_quiet && last_char != '\n') putc('\n', stdout); /* Kill if it is not dead yet anyway */ @@ -3370,16 +3548,17 @@ int main(int argc, char *argv[]) { r = wait_for_container(pid, &container_status); pid = 0; - if (r < 0) { + if (r < 0) /* We failed to wait for the container, or the * container exited abnormally */ - r = EXIT_FAILURE; - break; - } else if (r > 0 || container_status == CONTAINER_TERMINATED) + goto finish; + else if (r > 0 || container_status == CONTAINER_TERMINATED){ /* The container exited with a non-zero * status, or with zero status and no reboot * was requested. */ + ret = r; break; + } /* CONTAINER_REBOOTED, loop again */ @@ -3394,7 +3573,8 @@ int main(int argc, char *argv[]) { * restart. This is necessary since we might * have cgroup parameters set we want to have * flushed out. */ - r = 133; + ret = 133; + r = 0; break; } } @@ -3409,7 +3589,24 @@ finish: if (pid > 0) kill(pid, SIGKILL); + if (remove_subvol && arg_directory) { + int k; + + k = btrfs_subvol_remove(arg_directory); + if (k < 0) + log_warning_errno(k, "Cannot remove subvolume '%s', ignoring: %m", arg_directory); + } + + if (arg_machine) { + const char *p; + + p = strappenda("/run/systemd/nspawn/propagate", arg_machine); + (void) rm_rf(p, false, true, false); + } + free(arg_directory); + free(arg_template); + free(arg_image); free(arg_machine); free(arg_user); strv_free(arg_setenv); @@ -3419,5 +3616,5 @@ finish: strv_free(arg_bind_ro); strv_free(arg_tmpfs); - return r; + return r < 0 ? EXIT_FAILURE : ret; }