X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=416d4a69b494cc126a7f03908ace34d1b0bd2a78;hp=1a3e41f4037ae205923110cbf7193b70f0e24e81;hb=6606089752df90f3eeb4924af109046f1c73554c;hpb=f2d88580b50e3c173dcc2838f92fa85291bc5495 diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 1a3e41f40..416d4a69b 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -75,6 +75,7 @@ static char *arg_directory = NULL; static char *arg_user = NULL; static char **arg_controllers = NULL; static char *arg_uuid = NULL; +static char *arg_machine = NULL; static bool arg_private_network = false; static bool arg_read_only = false; static bool arg_boot = false; @@ -113,13 +114,14 @@ static int help(void) { printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n" "Spawn a minimal namespace container for debugging, testing and building.\n\n" " -h --help Show this help\n" - " --version Print version string\n" + " --version Print version string\n" " -D --directory=NAME Root directory 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" " -C --controllers=LIST Put the container in specified comma-separated\n" " cgroup hierarchies\n" " --uuid=UUID Set a specific machine UUID for the container\n" + " -M --machine=NAME Set the machine name for the container\n" " --private-network Disable network in container\n" " --read-only Mount the root directory read-only\n" " --capability=CAP In addition to the default, retain specified\n" @@ -161,6 +163,7 @@ static int parse_argv(int argc, char *argv[]) { { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL }, { "bind", required_argument, NULL, ARG_BIND }, { "bind-ro", required_argument, NULL, ARG_BIND_RO }, + { "machine", required_argument, NULL, 'M' }, { NULL, 0, NULL, 0 } }; @@ -194,22 +197,19 @@ static int parse_argv(int argc, char *argv[]) { case 'u': free(arg_user); - if (!(arg_user = strdup(optarg))) { - log_error("Failed to duplicate user name."); - return -ENOMEM; - } + arg_user = strdup(optarg); + if (!arg_user) + return log_oom(); break; case 'C': strv_free(arg_controllers); arg_controllers = strv_split(optarg, ","); - if (!arg_controllers) { - log_error("Failed to split controllers list."); - return -ENOMEM; - } - strv_uniq(arg_controllers); + if (!arg_controllers) + return log_oom(); + cg_shorten_controllers(arg_controllers); break; case ARG_PRIVATE_NETWORK: @@ -224,6 +224,19 @@ static int parse_argv(int argc, char *argv[]) { arg_uuid = optarg; break; + case 'M': + if (!hostname_is_valid(optarg)) { + log_error("Invalid machine name: %s", optarg); + return -EINVAL; + } + + free(arg_machine); + arg_machine = strdup(optarg); + if (!arg_machine) + return log_oom(); + + break; + case ARG_READ_ONLY: arg_read_only = true; break; @@ -528,7 +541,7 @@ static int setup_boot_id(const char *dest) { SD_ID128_FORMAT_VAL(rnd)); char_array_0(as_uuid); - r = write_one_line_file(from, as_uuid); + r = write_string_file(from, as_uuid); if (r < 0) { log_error("Failed to write boot id: %s", strerror(-r)); return r; @@ -537,8 +550,8 @@ static int setup_boot_id(const char *dest) { if (mount(from, to, "bind", MS_BIND, NULL) < 0) { log_error("Failed to bind mount boot id: %m"); r = -errno; - } else - mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL); + } else if (mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL)) + log_warning("Failed to make boot id read-only: %m"); unlink(from); return r; @@ -674,8 +687,11 @@ static int setup_kmsg(const char *dest, int kmsg_socket) { union { struct cmsghdr cmsghdr; uint8_t buf[CMSG_SPACE(sizeof(int))]; - } control; - struct msghdr mh; + } control = {}; + struct msghdr mh = { + .msg_control = &control, + .msg_controllen = sizeof(control), + }; struct cmsghdr *cmsg; assert(dest); @@ -716,12 +732,6 @@ static int setup_kmsg(const char *dest, int kmsg_socket) { return -errno; } - zero(mh); - zero(control); - - mh.msg_control = &control; - mh.msg_controllen = sizeof(control); - cmsg = CMSG_FIRSTHDR(&mh); cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; @@ -746,25 +756,11 @@ static int setup_kmsg(const char *dest, int kmsg_socket) { } static int setup_hostname(void) { - char *hn; - int r = 0; - - hn = path_get_file_name(arg_directory); - if (hn) { - hn = strdup(hn); - if (!hn) - return -ENOMEM; - - hostname_cleanup(hn); - - if (!isempty(hn)) - if (sethostname(hn, strlen(hn)) < 0) - r = -errno; - free(hn); - } + if (sethostname(arg_machine, strlen(arg_machine)) < 0) + return -errno; - return r; + return 0; } static int setup_journal(const char *directory) { @@ -899,22 +895,27 @@ static int setup_journal(const char *directory) { return 0; } -static int drop_capabilities(void) { - return capability_bounding_set_drop(~arg_retain, false); -} - -static int is_os_tree(const char *path) { +static int setup_cgroup(const char *path) { + char **c; int r; - char *p; - /* We use /bin/sh as flag file if something is an OS */ - if (asprintf(&p, "%s/bin/sh", path) < 0) - return -ENOMEM; + r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, path, 1); + if (r < 0) { + log_error("Failed to create cgroup: %s", strerror(-r)); + return r; + } - r = access(p, F_OK); - free(p); + STRV_FOREACH(c, arg_controllers) { + r = cg_create_and_attach(*c, path, 1); + if (r < 0) + log_warning("Failed to create cgroup in controller %s: %s", *c, strerror(-r)); + } - return r < 0 ? 0 : 1; + return 0; +} + +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) { @@ -1162,9 +1163,9 @@ finish: int main(int argc, char *argv[]) { pid_t pid = 0; int r = EXIT_FAILURE, k; - char *oldcg = NULL, *newcg = NULL; - char **controller = NULL; - int master = -1, n_fd_passed; + _cleanup_free_ char *machine_root = NULL, *newcg = NULL; + _cleanup_close_ int master = -1; + int n_fd_passed; const char *console = NULL; struct termios saved_attr, raw_attr; sigset_t mask; @@ -1196,6 +1197,20 @@ int main(int argc, char *argv[]) { path_kill_slashes(arg_directory); + if (!arg_machine) { + arg_machine = strdup(path_get_file_name(arg_directory)); + if (!arg_machine) { + log_oom(); + goto finish; + } + + hostname_cleanup(arg_machine); + if (isempty(arg_machine)) { + log_error("Failed to determine machine name automatically, please use -M."); + goto finish; + } + } + if (geteuid() != 0) { log_error("Need to be root."); goto finish; @@ -1211,7 +1226,7 @@ int main(int argc, char *argv[]) { goto finish; } - if (is_os_tree(arg_directory) <= 0) { + if (path_is_os_tree(arg_directory) <= 0) { log_error("Directory %s doesn't look like an OS root directory. Refusing.", arg_directory); goto finish; } @@ -1228,27 +1243,26 @@ int main(int argc, char *argv[]) { fdset_close_others(fds); log_open(); - k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg); + k = cg_get_machine_path(&machine_root); if (k < 0) { - log_error("Failed to determine current cgroup: %s", strerror(-k)); + log_error("Failed to determine machine cgroup path: %s", strerror(-k)); goto finish; } - if (asprintf(&newcg, "%s/nspawn-%lu", oldcg, (unsigned long) getpid()) < 0) { + newcg = strjoin(machine_root, "/", arg_machine, NULL); + if (!newcg) { log_error("Failed to allocate cgroup path."); goto finish; } - k = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, newcg, 0); - if (k < 0) { - log_error("Failed to create cgroup: %s", strerror(-k)); - goto finish; - } + r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, newcg, false); + if (r <= 0 && r != -ENOENT) { + log_error("Container already running."); + + free(newcg); + newcg = NULL; - STRV_FOREACH(controller, arg_controllers) { - k = cg_create_and_attach(*controller, newcg, 0); - if (k < 0) - log_warning("Failed to create cgroup in controller %s: %s", *controller, strerror(-k)); + goto finish; } master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); @@ -1282,7 +1296,7 @@ int main(int argc, char *argv[]) { } if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) { - log_error("Failed to create kmsg socket pair"); + log_error("Failed to create kmsg socket pair."); goto finish; } @@ -1385,6 +1399,9 @@ int main(int argc, char *argv[]) { goto child_fail; } + if (setup_cgroup(newcg) < 0) + goto child_fail; + /* Mark everything as slave, so that we still * receive mounts from the real root, but don't * propagate mounts to the real root. */ @@ -1550,7 +1567,7 @@ int main(int argc, char *argv[]) { } if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) || - (asprintf((char **)(envp + n_env++), "LISTEN_PID=%lu", (unsigned long) getpid()) < 0)) { + (asprintf((char **)(envp + n_env++), "LISTEN_PID=%lu", (unsigned long) 1) < 0)) { log_oom(); goto child_fail; } @@ -1589,7 +1606,7 @@ int main(int argc, char *argv[]) { _exit(EXIT_FAILURE); } - log_info("Init process in the container running as PID %d", pid); + log_info("Init process in the container running as PID %lu.", (unsigned long) pid); close_nointr_nofail(pipefd[0]); close_nointr_nofail(pipefd[1]); @@ -1643,21 +1660,14 @@ finish: if (saved_attr_valid) tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr); - if (master >= 0) - close_nointr_nofail(master); - close_pipe(kmsg_socket_pair); - if (oldcg) - cg_attach(SYSTEMD_CGROUP_CONTROLLER, oldcg, 0); - if (newcg) cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, newcg, true); free(arg_directory); + free(arg_machine); strv_free(arg_controllers); - free(oldcg); - free(newcg); fdset_free(fds);