chiark / gitweb /
tmpfiles: introduce the concept of unsafe operations
[elogind.git] / src / tmpfiles / tmpfiles.c
index 51827f01afdd77fb23c97b5f8e817c75ae1276ca..881c3b0d7818fe963bb4dfa5435f3599efa285d6 100644 (file)
@@ -51,6 +51,8 @@
 #include "set.h"
 #include "conf-files.h"
 #include "capability.h"
+#include "specifier.h"
+#include "build.h"
 
 /* This reads all files listed in /etc/tmpfiles.d/?*.conf and creates
  * them in the file system. This is intended to be used to create
@@ -68,6 +70,7 @@ typedef enum ItemType {
         CREATE_SYMLINK = 'L',
         CREATE_CHAR_DEVICE = 'c',
         CREATE_BLOCK_DEVICE = 'b',
+        ADJUST_MODE = 'm',
 
         /* These ones take globs */
         IGNORE_PATH = 'x',
@@ -104,8 +107,10 @@ static Set *unix_sockets = NULL;
 static bool arg_create = false;
 static bool arg_clean = false;
 static bool arg_remove = false;
+static bool arg_unsafe = false;
 
-static const char *arg_prefix = NULL;
+static char **include_prefixes = NULL;
+static char **exclude_prefixes = NULL;
 
 static const char conf_file_dirs[] =
         "/etc/tmpfiles.d\0"
@@ -135,7 +140,7 @@ static struct Item* find_glob(Hashmap *h, const char *match) {
 }
 
 static void load_unix_sockets(void) {
-        FILE _cleanup_fclose_ *f = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         char line[LINE_MAX];
 
         if (unix_sockets)
@@ -186,13 +191,9 @@ static void load_unix_sockets(void) {
 
                 path_kill_slashes(s);
 
-                k = set_put(unix_sockets, s);
-                if (k < 0) {
-                        free(s);
-
-                        if (k != -EEXIST)
-                                goto fail;
-                }
+                k = set_consume(unix_sockets, s);
+                if (k < 0 && k != -EEXIST)
+                        goto fail;
         }
 
         return;
@@ -259,8 +260,8 @@ static int dir_cleanup(
                 dev_t rootdev,
                 bool mountpoint,
                 int maxdepth,
-                bool keep_this_level)
-{
+                bool keep_this_level) {
+
         struct dirent *dent;
         struct timespec times[2];
         bool deleted = false;
@@ -269,19 +270,22 @@ static int dir_cleanup(
         while ((dent = readdir(d))) {
                 struct stat s;
                 usec_t age;
-                char _cleanup_free_ *sub_path = NULL;
+                _cleanup_free_ char *sub_path = NULL;
 
                 if (streq(dent->d_name, ".") ||
                     streq(dent->d_name, ".."))
                         continue;
 
                 if (fstatat(dirfd(d), dent->d_name, &s, AT_SYMLINK_NOFOLLOW) < 0) {
+                        if (errno == ENOENT)
+                                continue;
 
-                        if (errno != ENOENT) {
+                        /* FUSE, NFS mounts, SELinux might return EACCES */
+                        if (errno == EACCES)
+                                log_debug("stat(%s/%s) failed: %m", p, dent->d_name);
+                        else
                                 log_error("stat(%s/%s) failed: %m", p, dent->d_name);
-                                r = -errno;
-                        }
-
+                        r = -errno;
                         continue;
                 }
 
@@ -321,7 +325,7 @@ static int dir_cleanup(
                         if (maxdepth <= 0)
                                 log_warning("Reached max depth on %s.", sub_path);
                         else {
-                                DIR _cleanup_closedir_ *sub_dir;
+                                _cleanup_closedir_ DIR *sub_dir;
                                 int q;
 
                                 sub_dir = xopendirat(dirfd(d), dent->d_name, O_NOFOLLOW|O_NOATIME);
@@ -357,7 +361,7 @@ static int dir_cleanup(
                                 continue;
 
                         if (i->type != IGNORE_DIRECTORY_PATH || !streq(dent->d_name, p)) {
-                                log_debug("rmdir '%s'\n", sub_path);
+                                log_debug("rmdir '%s'", sub_path);
 
                                 if (unlinkat(dirfd(d), dent->d_name, AT_REMOVEDIR) < 0) {
                                         if (errno != ENOENT && errno != ENOTEMPTY) {
@@ -405,7 +409,7 @@ static int dir_cleanup(
                         if (age >= cutoff)
                                 continue;
 
-                        log_debug("unlink '%s'\n", sub_path);
+                        log_debug("unlink '%s'", sub_path);
 
                         if (unlinkat(dirfd(d), dent->d_name, 0) < 0) {
                                 if (errno != ENOENT) {
@@ -431,12 +435,16 @@ finish:
         return r;
 }
 
-static int item_set_perms(Item *i, const char *path) {
+static int item_set_perms_full(Item *i, const char *path, bool ignore_enoent) {
+        int r;
+
         /* not using i->path directly because it may be a glob */
         if (i->mode_set)
                 if (chmod(path, i->mode) < 0) {
-                        log_error("chmod(%s) failed: %m", path);
-                        return -errno;
+                        if (errno != ENOENT || !ignore_enoent) {
+                                log_error("chmod(%s) failed: %m", path);
+                                return -errno;
+                        }
                 }
 
         if (i->uid_set || i->gid_set)
@@ -444,16 +452,25 @@ static int item_set_perms(Item *i, const char *path) {
                           i->uid_set ? i->uid : (uid_t) -1,
                           i->gid_set ? i->gid : (gid_t) -1) < 0) {
 
-                        log_error("chown(%s) failed: %m", path);
-                        return -errno;
+                        if (errno != ENOENT || !ignore_enoent) {
+                                log_error("chown(%s) failed: %m", path);
+                                return -errno;
+                        }
                 }
 
-        return label_fix(path, false, false);
+        r = label_fix(path, false, false);
+        return r == -ENOENT && ignore_enoent ? 0 : r;
+}
+
+static int item_set_perms(Item *i, const char *path) {
+        return item_set_perms_full(i, path, false);
 }
 
 static int write_one_file(Item *i, const char *path) {
-        int r, e, fd, flags;
+        int e, flags;
+        int fd = -1;
         struct stat st;
+        int r = 0;
 
         flags = i->type == CREATE_FILE ? O_CREAT|O_APPEND :
                 i->type == TRUNCATE_FILE ? O_CREAT|O_TRUNC : 0;
@@ -515,7 +532,7 @@ static int write_one_file(Item *i, const char *path) {
 }
 
 static int recursive_relabel_children(Item *i, const char *path) {
-        DIR _cleanup_closedir_ *d;
+        _cleanup_closedir_ DIR *d;
         int ret = 0;
 
         /* This returns the first error we run into, but nevertheless
@@ -527,15 +544,15 @@ static int recursive_relabel_children(Item *i, const char *path) {
 
         for (;;) {
                 struct dirent *de;
-                union dirent_storage buf;
                 bool is_dir;
                 int r;
-                char _cleanup_free_ *entry_path = NULL;
+                _cleanup_free_ char *entry_path = NULL;
 
-                r = readdir_r(d, &buf.de, &de);
-                if (r != 0) {
+                errno = 0;
+                de = readdir(d);
+                if (!de && errno != 0) {
                         if (ret == 0)
-                                ret = -r;
+                                ret = -errno;
                         break;
                 }
 
@@ -601,12 +618,12 @@ static int recursive_relabel(Item *i, const char *path) {
 
 static int glob_item(Item *i, int (*action)(Item *, const char *)) {
         int r = 0, k;
-        glob_t g = {};
+        _cleanup_globfree_ glob_t g = {};
         char **fn;
 
         errno = 0;
-        if ((k = glob(i->path, GLOB_NOSORT|GLOB_BRACE, NULL, &g)) != 0) {
-
+        k = glob(i->path, GLOB_NOSORT|GLOB_BRACE, NULL, &g);
+        if (k != 0)
                 if (k != GLOB_NOMATCH) {
                         if (errno > 0)
                                 errno = EIO;
@@ -614,19 +631,20 @@ static int glob_item(Item *i, int (*action)(Item *, const char *)) {
                         log_error("glob(%s) failed: %m", i->path);
                         return -errno;
                 }
-        }
 
-        STRV_FOREACH(fn, g.gl_pathv)
-                if ((k = action(i, *fn)) < 0)
+        STRV_FOREACH(fn, g.gl_pathv) {
+                k = action(i, *fn);
+                if (k < 0)
                         r = k;
+        }
 
-        globfree(&g);
         return r;
 }
 
 static int create_item(Item *i) {
-        int r, e;
+        int e;
         struct stat st;
+        int r = 0;
 
         assert(i);
 
@@ -644,6 +662,7 @@ static int create_item(Item *i) {
                 if (r < 0)
                         return r;
                 break;
+
         case WRITE_FILE:
                 r = glob_item(i, write_one_file);
                 if (r < 0)
@@ -651,6 +670,13 @@ static int create_item(Item *i) {
 
                 break;
 
+        case ADJUST_MODE:
+                r = item_set_perms_full(i, i->path, true);
+                if (r < 0)
+                        return r;
+
+                break;
+
         case TRUNCATE_DIRECTORY:
         case CREATE_DIRECTORY:
 
@@ -743,7 +769,7 @@ static int create_item(Item *i) {
 
                 if (have_effective_cap(CAP_MKNOD) == 0) {
                         /* In a container we lack CAP_MKNOD. We
-                        shouldnt attempt to create the device node in
+                        shouldn't attempt to create the device node in
                         that case to avoid noise, and we don't support
                         virtualized devices in containers anyway. */
 
@@ -787,7 +813,7 @@ static int create_item(Item *i) {
 
                 r = glob_item(i, item_set_perms);
                 if (r < 0)
-                        return 0;
+                        return r;
                 break;
 
         case RECURSIVE_RELABEL_PATH:
@@ -821,6 +847,7 @@ static int remove_item_instance(Item *i, const char *instance) {
         case RELABEL_PATH:
         case RECURSIVE_RELABEL_PATH:
         case WRITE_FILE:
+        case ADJUST_MODE:
                 break;
 
         case REMOVE_PATH:
@@ -866,6 +893,7 @@ static int remove_item(Item *i) {
         case RELABEL_PATH:
         case RECURSIVE_RELABEL_PATH:
         case WRITE_FILE:
+        case ADJUST_MODE:
                 break;
 
         case REMOVE_PATH:
@@ -879,7 +907,7 @@ static int remove_item(Item *i) {
 }
 
 static int clean_item_instance(Item *i, const char* instance) {
-        DIR _cleanup_closedir_ *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         struct stat s, ps;
         bool mountpoint;
         int r;
@@ -975,6 +1003,9 @@ static void item_free(Item *i) {
         free(i);
 }
 
+DEFINE_TRIVIAL_CLEANUP_FUNC(Item*, item_free);
+#define _cleanup_item_free_ _cleanup_(item_freep)
+
 static bool item_equal(Item *a, Item *b) {
         assert(a);
         assert(b);
@@ -1016,11 +1047,38 @@ static bool item_equal(Item *a, Item *b) {
         return true;
 }
 
+static bool should_include_path(const char *path) {
+        char **prefix;
+
+        STRV_FOREACH(prefix, exclude_prefixes) {
+                if (path_startswith(path, *prefix))
+                        return false;
+        }
+
+        STRV_FOREACH(prefix, include_prefixes) {
+                if (path_startswith(path, *prefix))
+                        return true;
+        }
+
+        /* no matches, so we should include this path only if we
+         * have no whitelist at all */
+        return strv_length(include_prefixes) == 0;
+}
+
 static int parse_line(const char *fname, unsigned line, const char *buffer) {
-        Item _cleanup_free_ *i = NULL;
+
+        static const Specifier specifier_table[] = {
+                { 'm', specifier_machine_id, NULL },
+                { 'b', specifier_boot_id, NULL },
+                { 'H', specifier_host_name, NULL },
+                { 'v', specifier_kernel_release, NULL },
+                {}
+        };
+
+        _cleanup_item_free_ Item *i = NULL;
         Item *existing;
-        char _cleanup_free_
-                *mode = NULL, *user = NULL, *group = NULL, *age = NULL;
+        _cleanup_free_ char
+                *action = NULL, *mode = NULL, *user = NULL, *group = NULL, *age = NULL, *path = NULL;
         char type;
         Hashmap *h;
         int r, n = -1;
@@ -1029,14 +1087,10 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
         assert(line >= 1);
         assert(buffer);
 
-        i = new0(Item, 1);
-        if (!i)
-                return log_oom();
-
         r = sscanf(buffer,
-                   "%c %ms %ms %ms %ms %ms %n",
-                   &type,
-                   &i->path,
+                   "%ms %ms %ms %ms %ms %ms %n",
+                   &action,
+                   &path,
                    &mode,
                    &user,
                    &group,
@@ -1047,6 +1101,24 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
                 return -EIO;
         }
 
+        if (strlen(action) > 2 || (strlen(action) > 1 && action[1] != '!')) {
+                log_error("[%s:%u] Unknown modifier '%s'", fname, line, action);
+                return -EINVAL;
+        } else if (strlen(action) > 1 && !arg_unsafe)
+                return 0;
+
+        type = action[0];
+
+        i = new0(Item, 1);
+        if (!i)
+                return log_oom();
+
+        r = specifier_printf(path, specifier_table, NULL, &i->path);
+        if (r < 0) {
+                log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, path);
+                return r;
+        }
+
         if (n >= 0)  {
                 n += strspn(buffer+n, WHITESPACE);
                 if (buffer[n] != 0 && (buffer[n] != '-' || buffer[n+1] != 0)) {
@@ -1069,6 +1141,7 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
         case RECURSIVE_REMOVE_PATH:
         case RELABEL_PATH:
         case RECURSIVE_RELABEL_PATH:
+        case ADJUST_MODE:
                 break;
 
         case CREATE_SYMLINK:
@@ -1117,7 +1190,7 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
 
         path_kill_slashes(i->path);
 
-        if (arg_prefix && !path_startswith(i->path, arg_prefix))
+        if (!should_include_path(i->path))
                 return 0;
 
         if (user && !streq(user, "-")) {
@@ -1202,11 +1275,14 @@ static int help(void) {
 
         printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
                "Creates, deletes and cleans up volatile and temporary files and directories.\n\n"
-               "  -h --help             Show this help\n"
-               "     --create           Create marked files/directories\n"
-               "     --clean            Clean up marked directories\n"
-               "     --remove           Remove marked files/directories\n"
-               "     --prefix=PATH      Only apply rules that apply to paths with the specified prefix\n",
+               "  -h --help                 Show this help\n"
+               "     --version              Show package version\n"
+               "     --create               Create marked files/directories\n"
+               "     --clean                Clean up marked directories\n"
+               "     --remove               Remove marked files/directories\n"
+               "     --unsafe               Execute actions only safe at boot\n"
+               "     --prefix=PATH          Only apply rules that apply to paths with the specified prefix\n"
+               "     --exclude-prefix=PATH  Ignore rules that apply to paths with the specified prefix\n",
                program_invocation_short_name);
 
         return 0;
@@ -1215,19 +1291,25 @@ static int help(void) {
 static int parse_argv(int argc, char *argv[]) {
 
         enum {
+                ARG_VERSION = 0x100,
                 ARG_CREATE,
                 ARG_CLEAN,
                 ARG_REMOVE,
-                ARG_PREFIX
+                ARG_UNSAFE,
+                ARG_PREFIX,
+                ARG_EXCLUDE_PREFIX,
         };
 
         static const struct option options[] = {
-                { "help",      no_argument,       NULL, 'h'           },
-                { "create",    no_argument,       NULL, ARG_CREATE    },
-                { "clean",     no_argument,       NULL, ARG_CLEAN     },
-                { "remove",    no_argument,       NULL, ARG_REMOVE    },
-                { "prefix",    required_argument, NULL, ARG_PREFIX    },
-                { NULL,        0,                 NULL, 0             }
+                { "help",           no_argument,         NULL, 'h'                },
+                { "version",        no_argument,         NULL, ARG_VERSION        },
+                { "create",         no_argument,         NULL, ARG_CREATE         },
+                { "clean",          no_argument,         NULL, ARG_CLEAN          },
+                { "remove",         no_argument,         NULL, ARG_REMOVE         },
+                { "unsafe",         no_argument,         NULL, ARG_UNSAFE         },
+                { "prefix",         required_argument,   NULL, ARG_PREFIX         },
+                { "exclude-prefix", required_argument,   NULL, ARG_EXCLUDE_PREFIX },
+                {}
         };
 
         int c;
@@ -1240,7 +1322,11 @@ static int parse_argv(int argc, char *argv[]) {
                 switch (c) {
 
                 case 'h':
-                        help();
+                        return help();
+
+                case ARG_VERSION:
+                        puts(PACKAGE_STRING);
+                        puts(SYSTEMD_FEATURES);
                         return 0;
 
                 case ARG_CREATE:
@@ -1255,16 +1341,25 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_remove = true;
                         break;
 
+                case ARG_UNSAFE:
+                        arg_unsafe = true;
+                        break;
+
                 case ARG_PREFIX:
-                        arg_prefix = optarg;
+                        if (strv_extend(&include_prefixes, optarg) < 0)
+                                return log_oom();
+                        break;
+
+                case ARG_EXCLUDE_PREFIX:
+                        if (strv_extend(&exclude_prefixes, optarg) < 0)
+                                return log_oom();
                         break;
 
                 case '?':
                         return -EINVAL;
 
                 default:
-                        log_error("Unknown option code %c", c);
-                        return -EINVAL;
+                        assert_not_reached("Unhandled option");
                 }
         }
 
@@ -1277,11 +1372,12 @@ static int parse_argv(int argc, char *argv[]) {
 }
 
 static int read_config_file(const char *fn, bool ignore_enoent) {
-        FILE *f;
-        unsigned v = 0;
-        int r;
+        _cleanup_fclose_ FILE *f = NULL;
+        char line[LINE_MAX];
         Iterator iterator;
+        unsigned v = 0;
         Item *i;
+        int r;
 
         assert(fn);
 
@@ -1294,23 +1390,19 @@ static int read_config_file(const char *fn, bool ignore_enoent) {
                 return r;
         }
 
-        log_debug("apply: %s\n", fn);
-        for (;;) {
-                char line[LINE_MAX], *l;
+        FOREACH_LINE(line, f, break) {
+                char *l;
                 int k;
 
-                if (!(fgets(line, sizeof(line), f)))
-                        break;
-
                 v++;
 
                 l = strstrip(line);
                 if (*l == '#' || *l == 0)
                         continue;
 
-                if ((k = parse_line(fn, v, l)) < 0)
-                        if (r == 0)
-                                r = k;
+                k = parse_line(fn, v, l);
+                if (k < 0 && r == 0)
+                        r = k;
         }
 
         /* we have to determine age parameter for each entry of type X */
@@ -1347,8 +1439,6 @@ static int read_config_file(const char *fn, bool ignore_enoent) {
                         r = -EIO;
         }
 
-        fclose(f);
-
         return r;
 }
 
@@ -1421,6 +1511,8 @@ finish:
         hashmap_free(items);
         hashmap_free(globs);
 
+        strv_free(include_prefixes);
+
         set_free_free(unix_sockets);
 
         label_finish();