/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include "bus-error.h" #include "copy.h" #include "fd-util.h" #include "fileio.h" #include "fs-util.h" #include "mkdir-label.h" #include "pager.h" #include "path-util.h" #include "pretty-print.h" #include "process-util.h" #include "selinux-util.h" #include "stat-util.h" #include "systemctl-daemon-reload.h" #include "systemctl-edit.h" #include "systemctl-util.h" #include "systemctl.h" #include "terminal-util.h" #include "tmpfile-util.h" #define EDIT_MARKER_START "### Anything between here and the comment below will become the new contents of the file" #define EDIT_MARKER_END "### Lines below this comment will be discarded" int verb_cat(int argc, char *argv[], void *userdata) { _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL; _cleanup_(lookup_paths_free) LookupPaths lp = {}; _cleanup_strv_free_ char **names = NULL; sd_bus *bus; bool first = true; int r, rc = 0; /* Include all units by default — i.e. continue as if the --all option was used */ if (strv_isempty(arg_states)) arg_all = true; if (arg_transport != BUS_TRANSPORT_LOCAL) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot remotely cat units."); r = lookup_paths_init_or_warn(&lp, arg_scope, 0, arg_root); if (r < 0) return r; r = acquire_bus(BUS_MANAGER, &bus); if (r < 0) return r; r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL); if (r < 0) return log_error_errno(r, "Failed to expand names: %m"); r = maybe_extend_with_unit_dependencies(bus, &names); if (r < 0) return r; pager_open(arg_pager_flags); STRV_FOREACH(name, names) { _cleanup_free_ char *fragment_path = NULL; _cleanup_strv_free_ char **dropin_paths = NULL; r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &fragment_path, &dropin_paths); if (r == -ERFKILL) { printf("%s# Unit %s is masked%s.\n", ansi_highlight_magenta(), *name, ansi_normal()); continue; } if (r == -EKEYREJECTED) { printf("%s# Unit %s could not be loaded.%s\n", ansi_highlight_magenta(), *name, ansi_normal()); continue; } if (r < 0) return r; if (r == 0) { /* Skip units which have no on-disk counterpart, but propagate the error to the * user */ rc = -ENOENT; continue; } if (first) first = false; else puts(""); if (need_daemon_reload(bus, *name) > 0) /* ignore errors (<0), this is informational output */ fprintf(stderr, "%s# Warning: %s changed on disk, the version systemd has loaded is outdated.\n" "%s# This output shows the current version of the unit's original fragment and drop-in files.\n" "%s# If fragments or drop-ins were added or removed, they are not properly reflected in this output.\n" "%s# Run 'systemctl%s daemon-reload' to reload units.%s\n", ansi_highlight_red(), *name, ansi_highlight_red(), ansi_highlight_red(), ansi_highlight_red(), arg_scope == LOOKUP_SCOPE_SYSTEM ? "" : " --user", ansi_normal()); r = cat_files(fragment_path, dropin_paths, 0); if (r < 0) return r; } return rc; } static int create_edit_temp_file(const char *new_path, const char *original_path, char ** const original_unit_paths, char **ret_tmp_fn) { _cleanup_free_ char *t = NULL; int r; assert(new_path); assert(ret_tmp_fn); r = tempfn_random(new_path, NULL, &t); if (r < 0) return log_error_errno(r, "Failed to determine temporary filename for \"%s\": %m", new_path); r = mkdir_parents_label(new_path, 0755); if (r < 0) return log_error_errno(r, "Failed to create directories for \"%s\": %m", new_path); if (original_path) { r = mac_selinux_create_file_prepare(new_path, S_IFREG); if (r < 0) return r; r = copy_file(original_path, t, 0, 0644, 0, 0, COPY_REFLINK); if (r == -ENOENT) { r = touch(t); mac_selinux_create_file_clear(); if (r < 0) return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t); } else { mac_selinux_create_file_clear(); if (r < 0) return log_error_errno(r, "Failed to create temporary file for \"%s\": %m", new_path); } } else if (original_unit_paths) { _cleanup_free_ char *new_contents = NULL; _cleanup_fclose_ FILE *f = NULL; r = mac_selinux_create_file_prepare(new_path, S_IFREG); if (r < 0) return r; f = fopen(t, "we"); mac_selinux_create_file_clear(); if (!f) return log_error_errno(errno, "Failed to open \"%s\": %m", t); r = fchmod(fileno(f), 0644); if (r < 0) return log_error_errno(errno, "Failed to change mode of \"%s\": %m", t); r = read_full_file(new_path, &new_contents, NULL); if (r < 0 && r != -ENOENT) return log_error_errno(r, "Failed to read \"%s\": %m", new_path); fprintf(f, "### Editing %s\n" EDIT_MARKER_START "\n\n%s%s\n" EDIT_MARKER_END, new_path, strempty(new_contents), new_contents && endswith(new_contents, "\n") ? "" : "\n"); /* Add a comment with the contents of the original unit files */ STRV_FOREACH(path, original_unit_paths) { _cleanup_free_ char *contents = NULL; /* Skip the file that's being edited */ if (path_equal(*path, new_path)) continue; r = read_full_file(*path, &contents, NULL); if (r < 0) return log_error_errno(r, "Failed to read \"%s\": %m", *path); fprintf(f, "\n\n### %s", *path); if (!isempty(contents)) { _cleanup_free_ char *commented_contents = NULL; commented_contents = strreplace(strstrip(contents), "\n", "\n# "); if (!commented_contents) return log_oom(); fprintf(f, "\n# %s", commented_contents); } } r = fflush_and_check(f); if (r < 0) return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t); } *ret_tmp_fn = TAKE_PTR(t); return 0; } static int get_file_to_edit( const LookupPaths *paths, const char *name, char **ret_path) { _cleanup_free_ char *path = NULL, *run = NULL; assert(name); assert(ret_path); path = path_join(paths->persistent_config, name); if (!path) return log_oom(); if (arg_runtime) { run = path_join(paths->runtime_config, name); if (!run) return log_oom(); } if (arg_runtime) { if (access(path, F_OK) >= 0) return log_error_errno(SYNTHETIC_ERRNO(EEXIST), "Refusing to create \"%s\" because it would be overridden by \"%s\" anyway.", run, path); *ret_path = TAKE_PTR(run); } else *ret_path = TAKE_PTR(path); return 0; } static int unit_file_create_new( const LookupPaths *paths, const char *unit_name, const char *suffix, char ** const original_unit_paths, char **ret_new_path, char **ret_tmp_path) { _cleanup_free_ char *new_path = NULL, *tmp_path = NULL; const char *ending; int r; assert(unit_name); assert(ret_new_path); assert(ret_tmp_path); ending = strjoina(unit_name, suffix); r = get_file_to_edit(paths, ending, &new_path); if (r < 0) return r; r = create_edit_temp_file(new_path, NULL, original_unit_paths, &tmp_path); if (r < 0) return r; *ret_new_path = TAKE_PTR(new_path); *ret_tmp_path = TAKE_PTR(tmp_path); return 0; } static int unit_file_create_copy( const LookupPaths *paths, const char *unit_name, const char *fragment_path, char **ret_new_path, char **ret_tmp_path) { _cleanup_free_ char *new_path = NULL, *tmp_path = NULL; int r; assert(fragment_path); assert(unit_name); assert(ret_new_path); assert(ret_tmp_path); r = get_file_to_edit(paths, unit_name, &new_path); if (r < 0) return r; if (!path_equal(fragment_path, new_path) && access(new_path, F_OK) >= 0) { char response; r = ask_char(&response, "yn", "\"%s\" already exists. Overwrite with \"%s\"? [(y)es, (n)o] ", new_path, fragment_path); if (r < 0) return r; if (response != 'y') return log_warning_errno(SYNTHETIC_ERRNO(EKEYREJECTED), "%s skipped.", unit_name); } r = create_edit_temp_file(new_path, fragment_path, NULL, &tmp_path); if (r < 0) return r; *ret_new_path = TAKE_PTR(new_path); *ret_tmp_path = TAKE_PTR(tmp_path); return 0; } static int run_editor(char **paths) { int r; assert(paths); r = safe_fork("(editor)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG|FORK_WAIT, NULL); if (r < 0) return r; if (r == 0) { char **editor_args = NULL; size_t n_editor_args = 0, i = 1, argc; const char **args, *editor; argc = strv_length(paths)/2 + 1; /* SYSTEMD_EDITOR takes precedence over EDITOR which takes precedence over VISUAL. If * neither SYSTEMD_EDITOR nor EDITOR nor VISUAL are present, we try to execute well known * editors. */ editor = getenv("SYSTEMD_EDITOR"); if (!editor) editor = getenv("EDITOR"); if (!editor) editor = getenv("VISUAL"); if (!isempty(editor)) { editor_args = strv_split(editor, WHITESPACE); if (!editor_args) { (void) log_oom(); _exit(EXIT_FAILURE); } n_editor_args = strv_length(editor_args); argc += n_editor_args - 1; } args = newa(const char*, argc + 1); if (n_editor_args > 0) { args[0] = editor_args[0]; for (; i < n_editor_args; i++) args[i] = editor_args[i]; } STRV_FOREACH_PAIR(original_path, tmp_path, paths) args[i++] = *tmp_path; args[i] = NULL; if (n_editor_args > 0) execvp(args[0], (char* const*) args); FOREACH_STRING(name, "editor", "nano", "vim", "vi") { args[0] = name; execvp(name, (char* const*) args); /* We do not fail if the editor doesn't exist because we want to try each one of them * before failing. */ if (errno != ENOENT) { log_error_errno(errno, "Failed to execute %s: %m", name); _exit(EXIT_FAILURE); } } log_error("Cannot edit unit(s), no editor available. Please set either $SYSTEMD_EDITOR, $EDITOR or $VISUAL."); _exit(EXIT_FAILURE); } return 0; } static int find_paths_to_edit(sd_bus *bus, char **names, char ***paths) { _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL; _cleanup_(lookup_paths_free) LookupPaths lp = {}; int r; assert(names); assert(paths); r = lookup_paths_init(&lp, arg_scope, 0, arg_root); if (r < 0) return r; STRV_FOREACH(name, names) { _cleanup_free_ char *path = NULL, *new_path = NULL, *tmp_path = NULL, *tmp_name = NULL; _cleanup_strv_free_ char **unit_paths = NULL; const char *unit_name; r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &path, &unit_paths); if (r == -EKEYREJECTED) { /* If loading of the unit failed server side complete, then the server won't tell us * the unit file path. In that case, find the file client side. */ log_debug_errno(r, "Unit '%s' was not loaded correctly, retrying client-side.", *name); r = unit_find_paths(bus, *name, &lp, true, &cached_name_map, &cached_id_map, &path, &unit_paths); } if (r == -ERFKILL) return log_error_errno(r, "Unit '%s' masked, cannot edit.", *name); if (r < 0) return r; if (!path) { if (!arg_force) { log_info("Run 'systemctl edit%s --force --full %s' to create a new unit.", arg_scope == LOOKUP_SCOPE_GLOBAL ? " --global" : arg_scope == LOOKUP_SCOPE_USER ? " --user" : "", *name); return -ENOENT; } /* Create a new unit from scratch */ unit_name = *name; r = unit_file_create_new(&lp, unit_name, arg_full ? NULL : ".d/override.conf", NULL, &new_path, &tmp_path); } else { unit_name = basename(path); /* We follow unit aliases, but we need to propagate the instance */ if (unit_name_is_valid(*name, UNIT_NAME_INSTANCE) && unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) { _cleanup_free_ char *instance = NULL; r = unit_name_to_instance(*name, &instance); if (r < 0) return r; r = unit_name_replace_instance(unit_name, instance, &tmp_name); if (r < 0) return r; unit_name = tmp_name; } if (arg_full) r = unit_file_create_copy(&lp, unit_name, path, &new_path, &tmp_path); else { r = strv_prepend(&unit_paths, path); if (r < 0) return log_oom(); r = unit_file_create_new(&lp, unit_name, ".d/override.conf", unit_paths, &new_path, &tmp_path); } } if (r < 0) return r; r = strv_push_pair(paths, new_path, tmp_path); if (r < 0) return log_oom(); new_path = tmp_path = NULL; } return 0; } static int trim_edit_markers(const char *path) { _cleanup_free_ char *contents = NULL; char *contents_start = NULL; const char *contents_end = NULL; size_t size; int r; /* Trim out the lines between the two markers */ r = read_full_file(path, &contents, NULL); if (r < 0) return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path); size = strlen(contents); contents_start = strstr(contents, EDIT_MARKER_START); if (contents_start) contents_start += strlen(EDIT_MARKER_START); else contents_start = contents; contents_end = strstr(contents_start, EDIT_MARKER_END); if (contents_end) strshorten(contents_start, contents_end - contents_start); contents_start = strstrip(contents_start); /* Write new contents if the trimming actually changed anything */ if (strlen(contents) != size) { r = write_string_file(path, contents_start, WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_TRUNCATE | WRITE_STRING_FILE_AVOID_NEWLINE); if (r < 0) return log_error_errno(r, "Failed to modify temporary file \"%s\": %m", path); } return 0; } int verb_edit(int argc, char *argv[], void *userdata) { _cleanup_(lookup_paths_free) LookupPaths lp = {}; _cleanup_strv_free_ char **names = NULL; _cleanup_strv_free_ char **paths = NULL; sd_bus *bus; int r; if (!on_tty()) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units if not on a tty."); if (arg_transport != BUS_TRANSPORT_LOCAL) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units remotely."); r = lookup_paths_init_or_warn(&lp, arg_scope, 0, arg_root); if (r < 0) return r; r = mac_selinux_init(); if (r < 0) return r; r = acquire_bus(BUS_MANAGER, &bus); if (r < 0) return r; r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL); if (r < 0) return log_error_errno(r, "Failed to expand names: %m"); if (strv_isempty(names)) return log_error_errno(SYNTHETIC_ERRNO(ENOENT), "No units matched the specified patterns."); STRV_FOREACH(tmp, names) { r = unit_is_masked(bus, &lp, *tmp); if (r < 0) return r; if (r > 0) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit %s: unit is masked.", *tmp); } r = find_paths_to_edit(bus, names, &paths); if (r < 0) return r; if (strv_isempty(paths)) return -ENOENT; r = run_editor(paths); if (r < 0) goto end; STRV_FOREACH_PAIR(original, tmp, paths) { /* If the temporary file is empty we ignore it. This allows the user to cancel the * modification. */ r = trim_edit_markers(*tmp); if (r < 0) continue; if (null_or_empty_path(*tmp)) { log_warning("Editing \"%s\" canceled: temporary file is empty.", *original); continue; } r = rename(*tmp, *original); if (r < 0) { r = log_error_errno(errno, "Failed to rename \"%s\" to \"%s\": %m", *tmp, *original); goto end; } } r = 0; if (!arg_no_reload && !install_client_side()) { r = daemon_reload(ACTION_RELOAD, /* graceful= */ false); if (r > 0) r = 0; } end: STRV_FOREACH_PAIR(original, tmp, paths) { (void) unlink(*tmp); /* Removing empty dropin dirs */ if (!arg_full) { _cleanup_free_ char *dir = NULL; dir = dirname_malloc(*original); if (!dir) return log_oom(); /* No need to check if the dir is empty, rmdir does nothing if it is not the case. */ (void) rmdir(dir); } } return r; }