-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
/***
- This file is part of systemd.
-
Copyright 2010-2012 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
-#include <fcntl.h>
+#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <sys/statvfs.h>
+#include <sys/stat.h>
#include <unistd.h>
/* When we include libgen.h because we need dirname() we immediately
#undef basename
#include "alloc-util.h"
-#include "fd-util.h"
-#include "fileio.h"
+#include "extract-word.h"
#include "fs-util.h"
+//#include "glob-util.h"
#include "log.h"
#include "macro.h"
#include "missing.h"
#include "stat-util.h"
#include "string-util.h"
#include "strv.h"
-#include "util.h"
+#include "time-util.h"
+//#include "utf8.h"
bool path_is_absolute(const char *p) {
return p[0] == '/';
/* Makes every item in the list an absolute path by prepending
* the prefix, if specified and necessary */
- if (path_is_absolute(p) || !prefix)
+ if (path_is_absolute(p) || isempty(prefix))
return strdup(p);
- return strjoin(prefix, "/", p, NULL);
+ if (endswith(prefix, "/"))
+ return strjoin(prefix, p);
+ else
+ return strjoin(prefix, "/", p);
}
#endif // 0
+int safe_getcwd(char **ret) {
+ char *cwd;
+
+ cwd = get_current_dir_name();
+ if (!cwd)
+ return negative_errno();
+
+ /* Let's make sure the directory is really absolute, to protect us from the logic behind
+ * CVE-2018-1000001 */
+ if (cwd[0] != '/') {
+ free(cwd);
+ return -ENOMEDIUM;
+ }
+
+ *ret = cwd;
+ return 0;
+}
+
int path_make_absolute_cwd(const char *p, char **ret) {
char *c;
+ int r;
assert(p);
assert(ret);
else {
_cleanup_free_ char *cwd = NULL;
- cwd = get_current_dir_name();
- if (!cwd)
- return -errno;
+ r = safe_getcwd(&cwd);
+ if (r < 0)
+ return r;
- c = strjoin(cwd, "/", p, NULL);
+ if (endswith(cwd, "/"))
+ c = strjoin(cwd, p);
+ else
+ c = strjoin(cwd, "/", p);
}
if (!c)
return -ENOMEM;
#if 0 /// UNNEEDED by elogind
int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
- char *r, *p;
- unsigned n_parents;
+ char *f, *t, *r, *p;
+ unsigned n_parents = 0;
assert(from_dir);
assert(to_path);
/* Strips the common part, and adds ".." elements as necessary. */
- if (!path_is_absolute(from_dir))
+ if (!path_is_absolute(from_dir) || !path_is_absolute(to_path))
return -EINVAL;
- if (!path_is_absolute(to_path))
- return -EINVAL;
+ f = strdupa(from_dir);
+ t = strdupa(to_path);
+
+ path_simplify(f, true);
+ path_simplify(t, true);
/* Skip the common part. */
for (;;) {
- size_t a;
- size_t b;
+ size_t a, b;
- from_dir += strspn(from_dir, "/");
- to_path += strspn(to_path, "/");
+ f += *f == '/';
+ t += *t == '/';
- if (!*from_dir) {
- if (!*to_path)
+ if (!*f) {
+ if (!*t)
/* from_dir equals to_path. */
r = strdup(".");
else
/* from_dir is a parent directory of to_path. */
- r = strdup(to_path);
-
+ r = strdup(t);
if (!r)
return -ENOMEM;
- path_kill_slashes(r);
-
*_r = r;
return 0;
}
- if (!*to_path)
+ if (!*t)
break;
- a = strcspn(from_dir, "/");
- b = strcspn(to_path, "/");
+ a = strcspn(f, "/");
+ b = strcspn(t, "/");
- if (a != b)
- break;
-
- if (memcmp(from_dir, to_path, a) != 0)
+ if (a != b || memcmp(f, t, a) != 0)
break;
- from_dir += a;
- to_path += b;
+ f += a;
+ t += b;
}
/* If we're here, then "from_dir" has one or more elements that need to
* be replaced with "..". */
/* Count the number of necessary ".." elements. */
- for (n_parents = 0;;) {
- from_dir += strspn(from_dir, "/");
+ for (; *f;) {
+ size_t w;
- if (!*from_dir)
- break;
+ w = strcspn(f, "/");
+
+ /* If this includes ".." we can't do a simple series of "..", refuse */
+ if (w == 2 && f[0] == '.' && f[1] == '.')
+ return -EINVAL;
- from_dir += strcspn(from_dir, "/");
+ /* Count number of elements */
n_parents++;
+
+ f += w;
+ f += *f == '/';
}
- r = malloc(n_parents * 3 + strlen(to_path) + 1);
+ r = new(char, n_parents * 3 + strlen(t) + 1);
if (!r)
return -ENOMEM;
- for (p = r; n_parents > 0; n_parents--, p += 3)
- memcpy(p, "../", 3);
+ for (p = r; n_parents > 0; n_parents--)
+ p = mempcpy(p, "../", 3);
- strcpy(p, to_path);
- path_kill_slashes(r);
+ if (*t)
+ strcpy(p, t);
+ else
+ /* Remove trailing slash */
+ *(--p) = 0;
*_r = r;
return 0;
if (r < 0)
return r;
- free(*s);
- *s = t;
+ path_simplify(t, false);
+ free_and_replace(*s, t);
}
return 0;
}
#endif // 0
-char **path_strv_resolve(char **l, const char *prefix) {
+char **path_strv_resolve(char **l, const char *root) {
char **s;
unsigned k = 0;
bool enomem = false;
+ int r;
if (strv_isempty(l))
return l;
* changes on failure. */
STRV_FOREACH(s, l) {
- char *t, *u;
_cleanup_free_ char *orig = NULL;
+ char *t, *u;
if (!path_is_absolute(*s)) {
free(*s);
continue;
}
- if (prefix) {
+ if (root) {
orig = *s;
- t = strappend(prefix, orig);
+ t = prefix_root(root, orig);
if (!t) {
enomem = true;
continue;
} else
t = *s;
- errno = 0;
- u = canonicalize_file_name(t);
- if (!u) {
- if (errno == ENOENT) {
- if (prefix) {
- u = orig;
- orig = NULL;
- free(t);
- } else
- u = t;
- } else {
+ r = chase_symlinks(t, root, 0, &u);
+ if (r == -ENOENT) {
+ if (root) {
+ u = TAKE_PTR(orig);
free(t);
- if (errno == ENOMEM || errno == 0)
- enomem = true;
+ } else
+ u = t;
+ } else if (r < 0) {
+ free(t);
- continue;
- }
- } else if (prefix) {
+ if (r == -ENOMEM)
+ enomem = true;
+
+ continue;
+ } else if (root) {
char *x;
free(t);
- x = path_startswith(u, prefix);
+ x = path_startswith(u, root);
if (x) {
/* restore the slash if it was lost */
if (!startswith(x, "/"))
} else {
/* canonicalized path goes outside of
* prefix, keep the original path instead */
- free(u);
- u = orig;
- orig = NULL;
+ free_and_replace(u, orig);
}
} else
free(t);
return l;
}
-char **path_strv_resolve_uniq(char **l, const char *prefix) {
+char **path_strv_resolve_uniq(char **l, const char *root) {
if (strv_isempty(l))
return l;
- if (!path_strv_resolve(l, prefix))
+ if (!path_strv_resolve(l, root))
return NULL;
return strv_uniq(l);
}
-char *path_kill_slashes(char *path) {
+char *path_simplify(char *path, bool kill_dots) {
char *f, *t;
- bool slash = false;
+ bool slash = false, ignore_slash = false, absolute;
- /* Removes redundant inner and trailing slashes. Modifies the
- * passed string in-place.
+ assert(path);
+
+ /* Removes redundant inner and trailing slashes. Also removes unnecessary dots
+ * if kill_dots is true. Modifies the passed string in-place.
*
- * ///foo///bar/ becomes /foo/bar
+ * ///foo//./bar/. becomes /foo/./bar/. (if kill_dots is false)
+ * ///foo//./bar/. becomes /foo/bar (if kill_dots is true)
+ * .//./foo//./bar/. becomes ./foo/bar (if kill_dots is false)
+ * .//./foo//./bar/. becomes foo/bar (if kill_dots is true)
*/
- for (f = path, t = path; *f; f++) {
+ absolute = path_is_absolute(path);
+
+ f = path;
+ if (kill_dots && *f == '.' && IN_SET(f[1], 0, '/')) {
+ ignore_slash = true;
+ f++;
+ }
+
+ for (t = path; *f; f++) {
if (*f == '/') {
slash = true;
}
if (slash) {
+ if (kill_dots && *f == '.' && IN_SET(f[1], 0, '/'))
+ continue;
+
slash = false;
- *(t++) = '/';
+ if (ignore_slash)
+ ignore_slash = false;
+ else
+ *(t++) = '/';
}
*(t++) = *f;
}
- /* Special rule, if we are talking of the root directory, a
- trailing slash is good */
-
- if (t == path && slash)
+ /* Special rule, if we are talking of the root directory, a trailing slash is good */
+ if (absolute && t == path)
*(t++) = '/';
*t = 0;
assert(path);
assert(prefix);
+ /* Returns a pointer to the start of the first component after the parts matched by
+ * the prefix, iff
+ * - both paths are absolute or both paths are relative,
+ * and
+ * - each component in prefix in turn matches a component in path at the same position.
+ * An empty string will be returned when the prefix and path are equivalent.
+ *
+ * Returns NULL otherwise.
+ */
+
if ((path[0] == '/') != (prefix[0] == '/'))
return NULL;
return path_compare(a, b) == 0;
}
-bool path_equal_or_files_same(const char *a, const char *b) {
- return path_equal(a, b) || files_same(a, b) > 0;
+bool path_equal_or_files_same(const char *a, const char *b, int flags) {
+ return path_equal(a, b) || files_same(a, b, flags) > 0;
}
-#if 0 /// UNNEEDED by elogind
char* path_join(const char *root, const char *path, const char *rest) {
assert(path);
return strjoin(root, endswith(root, "/") ? "" : "/",
path[0] == '/' ? path+1 : path,
rest ? (endswith(path, "/") ? "" : "/") : NULL,
- rest && rest[0] == '/' ? rest+1 : rest,
- NULL);
+ rest && rest[0] == '/' ? rest+1 : rest);
else
return strjoin(path,
rest ? (endswith(path, "/") ? "" : "/") : NULL,
- rest && rest[0] == '/' ? rest+1 : rest,
- NULL);
+ rest && rest[0] == '/' ? rest+1 : rest);
}
int find_binary(const char *name, char **ret) {
return 0;
}
- /**
- * Plain getenv, not secure_getenv, because we want
- * to actually allow the user to pick the binary.
- */
+ /**
+ * Plain getenv, not secure_getenv, because we want
+ * to actually allow the user to pick the binary.
+ */
p = getenv("PATH");
if (!p)
p = DEFAULT_PATH;
break;
if (!path_is_absolute(element))
- continue;
+ continue;
- j = strjoin(element, "/", name, NULL);
+ j = strjoin(element, "/", name);
if (!j)
return -ENOMEM;
/* Found it! */
if (ret) {
- *ret = path_kill_slashes(j);
+ *ret = path_simplify(j, false);
j = NULL;
}
return last_error;
}
+#if 0 /// UNNEEDED by elogind
bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
bool changed = false;
const char* const* i;
assert(timestamp);
- if (paths == NULL)
+ if (!paths)
return false;
STRV_FOREACH(i, paths) {
if (r < 0)
return r;
- return !path_equal(d, "true") &&
- !path_equal(d, "/bin/true") &&
- !path_equal(d, "/usr/bin/true") &&
- !path_equal(d, "/dev/null");
+ return !PATH_IN_SET(d, "true"
+ "/bin/true",
+ "/usr/bin/true",
+ "/dev/null");
}
int fsck_exists(const char *fstype) {
mkfs = strjoina("mkfs.", fstype);
return binary_is_good(mkfs);
}
+#endif // 0
char *prefix_root(const char *root, const char *path) {
char *n, *p;
while (path[0] == '/' && path[1] == '/')
path++;
- if (isempty(root) || path_equal(root, "/"))
+ if (empty_or_root(root))
return strdup(path);
l = strlen(root) + 1 + strlen(path) + 1;
return n;
}
+#if 0 /// UNNEEDED by elogind
int parse_path_argument_and_warn(const char *path, bool suppress_root, char **arg) {
char *p;
int r;
if (r < 0)
return log_error_errno(r, "Failed to parse path \"%s\" and make it absolute: %m", path);
- path_kill_slashes(p);
- if (suppress_root && path_equal(p, "/"))
+ path_simplify(p, false);
+ if (suppress_root && empty_or_root(p))
p = mfree(p);
- free(*arg);
- *arg = p;
+ free_and_replace(*arg, p);
+
return 0;
}
#endif // 0
return dir2;
}
+const char *last_path_component(const char *path) {
+
+ /* Finds the last component of the path, preserving the optional trailing slash that signifies a directory.
+ *
+ * a/b/c → c
+ * a/b/c/ → c/
+ * x → x
+ * x/ → x/
+ * /y → y
+ * /y/ → y/
+ * / → /
+ * // → /
+ * /foo/a → a
+ * /foo/a/ → a/
+ *
+ * Also, the empty string is mapped to itself.
+ *
+ * This is different than basename(), which returns "" when a trailing slash is present.
+ */
+
+ unsigned l, k;
+
+ l = k = strlen(path);
+ if (l == 0) /* special case — an empty string */
+ return path;
+
+ while (k > 0 && path[k-1] == '/')
+ k--;
+
+ if (k == 0) /* the root directory */
+ return path + l - 1;
+
+ while (k > 0 && path[k-1] != '/')
+ k--;
+
+ return path + k;
+}
+
bool filename_is_valid(const char *p) {
const char *e;
if (isempty(p))
return false;
- if (streq(p, "."))
- return false;
-
- if (streq(p, ".."))
+ if (dot_or_dot_dot(p))
return false;
e = strchrnul(p, '/');
return true;
}
-bool path_is_safe(const char *p) {
+bool path_is_normalized(const char *p) {
if (isempty(p))
return false;
- if (streq(p, "..") || startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
+ if (dot_or_dot_dot(p))
+ return false;
+
+ if (startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
return false;
if (strlen(p)+1 > PATH_MAX)
return false;
- /* The following two checks are not really dangerous, but hey, they still are confusing */
- if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
+ if (startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
return false;
if (strstr(p, "//"))
return ret;
}
-bool hidden_file_allow_backup(const char *filename) {
- assert(filename);
+bool hidden_or_backup_file(const char *filename) {
+ const char *p;
- return
- filename[0] == '.' ||
- streq(filename, "lost+found") ||
- streq(filename, "aquota.user") ||
- streq(filename, "aquota.group") ||
- endswith(filename, ".rpmnew") ||
- endswith(filename, ".rpmsave") ||
- endswith(filename, ".rpmorig") ||
- endswith(filename, ".dpkg-old") ||
- endswith(filename, ".dpkg-new") ||
- endswith(filename, ".dpkg-tmp") ||
- endswith(filename, ".dpkg-dist") ||
- endswith(filename, ".dpkg-bak") ||
- endswith(filename, ".dpkg-backup") ||
- endswith(filename, ".dpkg-remove") ||
- endswith(filename, ".swp");
-}
-
-bool hidden_file(const char *filename) {
assert(filename);
- if (endswith(filename, "~"))
+ if (filename[0] == '.' ||
+ streq(filename, "lost+found") ||
+ streq(filename, "aquota.user") ||
+ streq(filename, "aquota.group") ||
+ endswith(filename, "~"))
return true;
- return hidden_file_allow_backup(filename);
+ p = strrchr(filename, '.');
+ if (!p)
+ return false;
+
+ /* Please, let's not add more entries to the list below. If external projects think it's a good idea to come up
+ * with always new suffixes and that everybody else should just adjust to that, then it really should be on
+ * them. Hence, in future, let's not add any more entries. Instead, let's ask those packages to instead adopt
+ * one of the generic suffixes/prefixes for hidden files or backups, possibly augmented with an additional
+ * string. Specifically: there's now:
+ *
+ * The generic suffixes "~" and ".bak" for backup files
+ * The generic prefix "." for hidden files
+ *
+ * Thus, if a new package manager "foopkg" wants its own set of ".foopkg-new", ".foopkg-old", ".foopkg-dist"
+ * or so registered, let's refuse that and ask them to use ".foopkg.new", ".foopkg.old" or ".foopkg~" instead.
+ */
+
+ return STR_IN_SET(p + 1,
+ "rpmnew",
+ "rpmsave",
+ "rpmorig",
+ "dpkg-old",
+ "dpkg-new",
+ "dpkg-tmp",
+ "dpkg-dist",
+ "dpkg-bak",
+ "dpkg-backup",
+ "dpkg-remove",
+ "ucf-new",
+ "ucf-old",
+ "ucf-dist",
+ "swp",
+ "bak",
+ "old",
+ "new");
}
#if 0 /// UNNEEDED by elogind
bool is_device_path(const char *path) {
- /* Returns true on paths that refer to a device, either in
- * sysfs or in /dev */
+ /* Returns true on paths that likely refer to a device, either by path in sysfs or to something in /dev */
+
+ return PATH_STARTSWITH_SET(path, "/dev/", "/sys/");
+}
+
+bool valid_device_node_path(const char *path) {
+
+ /* Some superficial checks whether the specified path is a valid device node path, all without looking at the
+ * actual device node. */
+
+ if (!PATH_STARTSWITH_SET(path, "/dev/", "/run/systemd/inaccessible/"))
+ return false;
+
+ if (endswith(path, "/")) /* can't be a device node if it ends in a slash */
+ return false;
+
+ return path_is_normalized(path);
+}
+
+bool valid_device_allow_pattern(const char *path) {
+ assert(path);
+
+ /* Like valid_device_node_path(), but also allows full-subsystem expressions, like DeviceAllow= and DeviceDeny=
+ * accept it */
+
+ if (startswith(path, "block-") ||
+ startswith(path, "char-"))
+ return true;
+
+ return valid_device_node_path(path);
+}
+
+int systemd_installation_has_version(const char *root, unsigned minimal_version) {
+ const char *pattern;
+ int r;
+
+ /* Try to guess if systemd installation is later than the specified version. This
+ * is hacky and likely to yield false negatives, particularly if the installation
+ * is non-standard. False positives should be relatively rare.
+ */
+
+ NULSTR_FOREACH(pattern,
+ /* /lib works for systems without usr-merge, and for systems with a sane
+ * usr-merge, where /lib is a symlink to /usr/lib. /usr/lib is necessary
+ * for Gentoo which does a merge without making /lib a symlink.
+ */
+ "lib/systemd/libsystemd-shared-*.so\0"
+ "lib64/systemd/libsystemd-shared-*.so\0"
+ "usr/lib/systemd/libsystemd-shared-*.so\0"
+ "usr/lib64/systemd/libsystemd-shared-*.so\0") {
+
+ _cleanup_strv_free_ char **names = NULL;
+ _cleanup_free_ char *path = NULL;
+ char *c, **name;
+
+ path = prefix_root(root, pattern);
+ if (!path)
+ return -ENOMEM;
+
+ r = glob_extend(&names, path);
+ if (r == -ENOENT)
+ continue;
+ if (r < 0)
+ return r;
+
+ assert_se(c = endswith(path, "*.so"));
+ *c = '\0'; /* truncate the glob part */
+
+ STRV_FOREACH(name, names) {
+ /* This is most likely to run only once, hence let's not optimize anything. */
+ char *t, *t2;
+ unsigned version;
+
+ t = startswith(*name, path);
+ if (!t)
+ continue;
+
+ t2 = endswith(t, ".so");
+ if (!t2)
+ continue;
+
+ t2[0] = '\0'; /* truncate the suffix */
+
+ r = safe_atou(t, &version);
+ if (r < 0) {
+ log_debug_errno(r, "Found libsystemd shared at \"%s.so\", but failed to parse version: %m", *name);
+ continue;
+ }
- return
- path_startswith(path, "/dev/") ||
- path_startswith(path, "/sys/");
+ log_debug("Found libsystemd shared at \"%s.so\", version %u (%s).",
+ *name, version,
+ version >= minimal_version ? "OK" : "too old");
+ if (version >= minimal_version)
+ return true;
+ }
+ }
+
+ return false;
}
#endif // 0
+
+bool dot_or_dot_dot(const char *path) {
+ if (!path)
+ return false;
+ if (path[0] != '.')
+ return false;
+ if (path[1] == 0)
+ return true;
+ if (path[1] != '.')
+ return false;
+
+ return path[2] == 0;
+}
+
+bool empty_or_root(const char *root) {
+
+ /* For operations relative to some root directory, returns true if the specified root directory is redundant,
+ * i.e. either / or NULL or the empty string or any equivalent. */
+
+ if (!root)
+ return true;
+
+ return root[strspn(root, "/")] == 0;
+}
+
+int path_simplify_and_warn(
+ char *path,
+ unsigned flag,
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *lvalue) {
+
+ bool absolute, fatal = flag & PATH_CHECK_FATAL;
+
+ assert(!FLAGS_SET(flag, PATH_CHECK_ABSOLUTE | PATH_CHECK_RELATIVE));
+
+ if (!utf8_is_valid(path)) {
+ log_syntax_invalid_utf8(unit, LOG_ERR, filename, line, path);
+ return -EINVAL;
+ }
+
+ if (flag & (PATH_CHECK_ABSOLUTE | PATH_CHECK_RELATIVE)) {
+ absolute = path_is_absolute(path);
+
+ if (!absolute && (flag & PATH_CHECK_ABSOLUTE)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is not absolute%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+
+ if (absolute && (flag & PATH_CHECK_RELATIVE)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is absolute%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+ }
+
+ path_simplify(path, true);
+
+ if (!path_is_normalized(path)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is not normalized%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+
+ return 0;
+}