1323 lines
38 KiB
C
1323 lines
38 KiB
C
/* SPDX-License-Identifier: LGPL-2.1-or-later */
|
||
|
||
#include "nm-sd-adapt-shared.h"
|
||
|
||
#include <errno.h>
|
||
#include <limits.h>
|
||
#include <stdio.h>
|
||
#include <stdlib.h>
|
||
#include <unistd.h>
|
||
|
||
/* When we include libgen.h because we need dirname() we immediately
|
||
* undefine basename() since libgen.h defines it as a macro to the
|
||
* POSIX version which is really broken. We prefer GNU basename(). */
|
||
#include <libgen.h>
|
||
#undef basename
|
||
|
||
#include "alloc-util.h"
|
||
#include "chase-symlinks.h"
|
||
#include "extract-word.h"
|
||
#include "fd-util.h"
|
||
#include "fs-util.h"
|
||
#include "log.h"
|
||
#include "macro.h"
|
||
#include "path-util.h"
|
||
#include "stat-util.h"
|
||
#include "string-util.h"
|
||
#include "strv.h"
|
||
#include "time-util.h"
|
||
|
||
#if 0 /* NM_IGNORED */
|
||
int path_split_and_make_absolute(const char *p, char ***ret) {
|
||
char **l;
|
||
int r;
|
||
|
||
assert(p);
|
||
assert(ret);
|
||
|
||
l = strv_split(p, ":");
|
||
if (!l)
|
||
return -ENOMEM;
|
||
|
||
r = path_strv_make_absolute_cwd(l);
|
||
if (r < 0) {
|
||
strv_free(l);
|
||
return r;
|
||
}
|
||
|
||
*ret = l;
|
||
return r;
|
||
}
|
||
|
||
char *path_make_absolute(const char *p, const char *prefix) {
|
||
assert(p);
|
||
|
||
/* Makes every item in the list an absolute path by prepending
|
||
* the prefix, if specified and necessary */
|
||
|
||
if (path_is_absolute(p) || isempty(prefix))
|
||
return strdup(p);
|
||
|
||
return path_join(prefix, p);
|
||
}
|
||
|
||
int safe_getcwd(char **ret) {
|
||
_cleanup_free_ char *cwd = NULL;
|
||
|
||
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] != '/')
|
||
return -ENOMEDIUM;
|
||
|
||
if (ret)
|
||
*ret = TAKE_PTR(cwd);
|
||
|
||
return 0;
|
||
}
|
||
|
||
int path_make_absolute_cwd(const char *p, char **ret) {
|
||
char *c;
|
||
int r;
|
||
|
||
assert(p);
|
||
assert(ret);
|
||
|
||
/* Similar to path_make_absolute(), but prefixes with the
|
||
* current working directory. */
|
||
|
||
if (path_is_absolute(p))
|
||
c = strdup(p);
|
||
else {
|
||
_cleanup_free_ char *cwd = NULL;
|
||
|
||
r = safe_getcwd(&cwd);
|
||
if (r < 0)
|
||
return r;
|
||
|
||
c = path_join(cwd, p);
|
||
}
|
||
if (!c)
|
||
return -ENOMEM;
|
||
|
||
*ret = c;
|
||
return 0;
|
||
}
|
||
|
||
int path_make_relative(const char *from, const char *to, char **ret) {
|
||
_cleanup_free_ char *result = NULL;
|
||
unsigned n_parents;
|
||
const char *f, *t;
|
||
int r, k;
|
||
char *p;
|
||
|
||
assert(from);
|
||
assert(to);
|
||
assert(ret);
|
||
|
||
/* Strips the common part, and adds ".." elements as necessary. */
|
||
|
||
if (!path_is_absolute(from) || !path_is_absolute(to))
|
||
return -EINVAL;
|
||
|
||
for (;;) {
|
||
r = path_find_first_component(&from, true, &f);
|
||
if (r < 0)
|
||
return r;
|
||
|
||
k = path_find_first_component(&to, true, &t);
|
||
if (k < 0)
|
||
return k;
|
||
|
||
if (r == 0) {
|
||
/* end of 'from' */
|
||
if (k == 0) {
|
||
/* from and to are equivalent. */
|
||
result = strdup(".");
|
||
if (!result)
|
||
return -ENOMEM;
|
||
} else {
|
||
/* 'to' is inside of 'from'. */
|
||
result = strdup(t);
|
||
if (!result)
|
||
return -ENOMEM;
|
||
|
||
path_simplify(result);
|
||
|
||
if (!path_is_valid(result))
|
||
return -EINVAL;
|
||
}
|
||
|
||
*ret = TAKE_PTR(result);
|
||
return 0;
|
||
}
|
||
|
||
if (r != k || !strneq(f, t, r))
|
||
break;
|
||
}
|
||
|
||
/* If we're here, then "from_dir" has one or more elements that need to
|
||
* be replaced with "..". */
|
||
|
||
for (n_parents = 1;; n_parents++) {
|
||
/* If this includes ".." we can't do a simple series of "..". */
|
||
r = path_find_first_component(&from, false, &f);
|
||
if (r < 0)
|
||
return r;
|
||
if (r == 0)
|
||
break;
|
||
}
|
||
|
||
if (isempty(t) && n_parents * 3 > PATH_MAX)
|
||
/* PATH_MAX is counted *with* the trailing NUL byte */
|
||
return -EINVAL;
|
||
|
||
result = new(char, n_parents * 3 + !isempty(t) + strlen_ptr(t));
|
||
if (!result)
|
||
return -ENOMEM;
|
||
|
||
for (p = result; n_parents > 0; n_parents--)
|
||
p = mempcpy(p, "../", 3);
|
||
|
||
if (isempty(t)) {
|
||
/* Remove trailing slash and terminate string. */
|
||
*(--p) = '\0';
|
||
*ret = TAKE_PTR(result);
|
||
return 0;
|
||
}
|
||
|
||
strcpy(p, t);
|
||
|
||
path_simplify(result);
|
||
|
||
if (!path_is_valid(result))
|
||
return -EINVAL;
|
||
|
||
*ret = TAKE_PTR(result);
|
||
return 0;
|
||
}
|
||
|
||
char* path_startswith_strv(const char *p, char **set) {
|
||
STRV_FOREACH(s, set) {
|
||
char *t;
|
||
|
||
t = path_startswith(p, *s);
|
||
if (t)
|
||
return t;
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
int path_strv_make_absolute_cwd(char **l) {
|
||
int r;
|
||
|
||
/* Goes through every item in the string list and makes it
|
||
* absolute. This works in place and won't rollback any
|
||
* changes on failure. */
|
||
|
||
STRV_FOREACH(s, l) {
|
||
char *t;
|
||
|
||
r = path_make_absolute_cwd(*s, &t);
|
||
if (r < 0)
|
||
return r;
|
||
|
||
path_simplify(t);
|
||
free_and_replace(*s, t);
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
char **path_strv_resolve(char **l, const char *root) {
|
||
unsigned k = 0;
|
||
bool enomem = false;
|
||
int r;
|
||
|
||
if (strv_isempty(l))
|
||
return l;
|
||
|
||
/* Goes through every item in the string list and canonicalize
|
||
* the path. This works in place and won't rollback any
|
||
* changes on failure. */
|
||
|
||
STRV_FOREACH(s, l) {
|
||
_cleanup_free_ char *orig = NULL;
|
||
char *t, *u;
|
||
|
||
if (!path_is_absolute(*s)) {
|
||
free(*s);
|
||
continue;
|
||
}
|
||
|
||
if (root) {
|
||
orig = *s;
|
||
t = path_join(root, orig);
|
||
if (!t) {
|
||
enomem = true;
|
||
continue;
|
||
}
|
||
} else
|
||
t = *s;
|
||
|
||
r = chase_symlinks(t, root, 0, &u, NULL);
|
||
if (r == -ENOENT) {
|
||
if (root) {
|
||
u = TAKE_PTR(orig);
|
||
free(t);
|
||
} else
|
||
u = t;
|
||
} else if (r < 0) {
|
||
free(t);
|
||
|
||
if (r == -ENOMEM)
|
||
enomem = true;
|
||
|
||
continue;
|
||
} else if (root) {
|
||
char *x;
|
||
|
||
free(t);
|
||
x = path_startswith(u, root);
|
||
if (x) {
|
||
/* restore the slash if it was lost */
|
||
if (!startswith(x, "/"))
|
||
*(--x) = '/';
|
||
|
||
t = strdup(x);
|
||
free(u);
|
||
if (!t) {
|
||
enomem = true;
|
||
continue;
|
||
}
|
||
u = t;
|
||
} else {
|
||
/* canonicalized path goes outside of
|
||
* prefix, keep the original path instead */
|
||
free_and_replace(u, orig);
|
||
}
|
||
} else
|
||
free(t);
|
||
|
||
l[k++] = u;
|
||
}
|
||
|
||
l[k] = NULL;
|
||
|
||
if (enomem)
|
||
return NULL;
|
||
|
||
return l;
|
||
}
|
||
|
||
char **path_strv_resolve_uniq(char **l, const char *root) {
|
||
|
||
if (strv_isempty(l))
|
||
return l;
|
||
|
||
if (!path_strv_resolve(l, root))
|
||
return NULL;
|
||
|
||
return strv_uniq(l);
|
||
}
|
||
#endif /* NM_IGNORED */
|
||
|
||
char *path_simplify(char *path) {
|
||
bool add_slash = false;
|
||
char *f = path;
|
||
int r;
|
||
|
||
assert(path);
|
||
|
||
/* Removes redundant inner and trailing slashes. Also removes unnecessary dots.
|
||
* Modifies the passed string in-place.
|
||
*
|
||
* ///foo//./bar/. becomes /foo/bar
|
||
* .//./foo//./bar/. becomes foo/bar
|
||
*/
|
||
|
||
if (isempty(path))
|
||
return path;
|
||
|
||
if (path_is_absolute(path))
|
||
f++;
|
||
|
||
for (const char *p = f;;) {
|
||
const char *e;
|
||
|
||
r = path_find_first_component(&p, true, &e);
|
||
if (r == 0)
|
||
break;
|
||
|
||
if (add_slash)
|
||
*f++ = '/';
|
||
|
||
if (r < 0) {
|
||
/* if path is invalid, then refuse to simplify remaining part. */
|
||
memmove(f, p, strlen(p) + 1);
|
||
return path;
|
||
}
|
||
|
||
memmove(f, e, r);
|
||
f += r;
|
||
|
||
add_slash = true;
|
||
}
|
||
|
||
/* Special rule, if we stripped everything, we need a "." for the current directory. */
|
||
if (f == path)
|
||
*f++ = '.';
|
||
|
||
*f = '\0';
|
||
return path;
|
||
}
|
||
|
||
char *path_startswith_full(const char *path, const char *prefix, bool accept_dot_dot) {
|
||
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;
|
||
|
||
for (;;) {
|
||
const char *p, *q;
|
||
int r, k;
|
||
|
||
r = path_find_first_component(&path, accept_dot_dot, &p);
|
||
if (r < 0)
|
||
return NULL;
|
||
|
||
k = path_find_first_component(&prefix, accept_dot_dot, &q);
|
||
if (k < 0)
|
||
return NULL;
|
||
|
||
if (k == 0)
|
||
return (char*) (p ?: path);
|
||
|
||
if (r != k)
|
||
return NULL;
|
||
|
||
if (!strneq(p, q, r))
|
||
return NULL;
|
||
}
|
||
}
|
||
|
||
int path_compare(const char *a, const char *b) {
|
||
int r;
|
||
|
||
/* Order NULL before non-NULL */
|
||
r = CMP(!!a, !!b);
|
||
if (r != 0)
|
||
return r;
|
||
|
||
/* A relative path and an absolute path must not compare as equal.
|
||
* Which one is sorted before the other does not really matter.
|
||
* Here a relative path is ordered before an absolute path. */
|
||
r = CMP(path_is_absolute(a), path_is_absolute(b));
|
||
if (r != 0)
|
||
return r;
|
||
|
||
for (;;) {
|
||
const char *aa, *bb;
|
||
int j, k;
|
||
|
||
j = path_find_first_component(&a, true, &aa);
|
||
k = path_find_first_component(&b, true, &bb);
|
||
|
||
if (j < 0 || k < 0) {
|
||
/* When one of paths is invalid, order invalid path after valid one. */
|
||
r = CMP(j < 0, k < 0);
|
||
if (r != 0)
|
||
return r;
|
||
|
||
/* fallback to use strcmp() if both paths are invalid. */
|
||
return strcmp(a, b);
|
||
}
|
||
|
||
/* Order prefixes first: "/foo" before "/foo/bar" */
|
||
if (j == 0) {
|
||
if (k == 0)
|
||
return 0;
|
||
return -1;
|
||
}
|
||
if (k == 0)
|
||
return 1;
|
||
|
||
/* Alphabetical sort: "/foo/aaa" before "/foo/b" */
|
||
r = memcmp(aa, bb, MIN(j, k));
|
||
if (r != 0)
|
||
return r;
|
||
|
||
/* Sort "/foo/a" before "/foo/aaa" */
|
||
r = CMP(j, k);
|
||
if (r != 0)
|
||
return r;
|
||
}
|
||
}
|
||
|
||
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;
|
||
}
|
||
|
||
bool path_equal_filename(const char *a, const char *b) {
|
||
_cleanup_free_ char *a_basename = NULL, *b_basename = NULL;
|
||
int r;
|
||
|
||
assert(a);
|
||
assert(b);
|
||
|
||
r = path_extract_filename(a, &a_basename);
|
||
if (r < 0) {
|
||
log_debug_errno(r, "Failed to parse basename of %s: %m", a);
|
||
return false;
|
||
}
|
||
r = path_extract_filename(b, &b_basename);
|
||
if (r < 0) {
|
||
log_debug_errno(r, "Failed to parse basename of %s: %m", b);
|
||
return false;
|
||
}
|
||
|
||
return path_equal(a_basename, b_basename);
|
||
}
|
||
|
||
char* path_extend_internal(char **x, ...) {
|
||
size_t sz, old_sz;
|
||
char *q, *nx;
|
||
const char *p;
|
||
va_list ap;
|
||
bool slash;
|
||
|
||
/* Joins all listed strings until the sentinel and places a "/" between them unless the strings end/begin
|
||
* already with one so that it is unnecessary. Note that slashes which are already duplicate won't be
|
||
* removed. The string returned is hence always equal to or longer than the sum of the lengths of each
|
||
* individual string.
|
||
*
|
||
* The first argument may be an already allocated string that is extended via realloc() if
|
||
* non-NULL. path_extend() and path_join() are macro wrappers around this function, making use of the
|
||
* first parameter to distinguish the two operations.
|
||
*
|
||
* Note: any listed empty string is simply skipped. This can be useful for concatenating strings of which some
|
||
* are optional.
|
||
*
|
||
* Examples:
|
||
*
|
||
* path_join("foo", "bar") → "foo/bar"
|
||
* path_join("foo/", "bar") → "foo/bar"
|
||
* path_join("", "foo", "", "bar", "") → "foo/bar" */
|
||
|
||
sz = old_sz = x ? strlen_ptr(*x) : 0;
|
||
va_start(ap, x);
|
||
while ((p = va_arg(ap, char*)) != POINTER_MAX) {
|
||
size_t add;
|
||
|
||
if (isempty(p))
|
||
continue;
|
||
|
||
add = 1 + strlen(p);
|
||
if (sz > SIZE_MAX - add) { /* overflow check */
|
||
va_end(ap);
|
||
return NULL;
|
||
}
|
||
|
||
sz += add;
|
||
}
|
||
va_end(ap);
|
||
|
||
nx = realloc(x ? *x : NULL, GREEDY_ALLOC_ROUND_UP(sz+1));
|
||
if (!nx)
|
||
return NULL;
|
||
if (x)
|
||
*x = nx;
|
||
|
||
if (old_sz > 0)
|
||
slash = nx[old_sz-1] == '/';
|
||
else {
|
||
nx[old_sz] = 0;
|
||
slash = true; /* no need to generate a slash anymore */
|
||
}
|
||
|
||
q = nx + old_sz;
|
||
|
||
va_start(ap, x);
|
||
while ((p = va_arg(ap, char*)) != POINTER_MAX) {
|
||
if (isempty(p))
|
||
continue;
|
||
|
||
if (!slash && p[0] != '/')
|
||
*(q++) = '/';
|
||
|
||
q = stpcpy(q, p);
|
||
slash = endswith(p, "/");
|
||
}
|
||
va_end(ap);
|
||
|
||
return nx;
|
||
}
|
||
|
||
#if 0 /* NM_IGNORED */
|
||
static int check_x_access(const char *path, int *ret_fd) {
|
||
_cleanup_close_ int fd = -1;
|
||
int r;
|
||
|
||
/* We need to use O_PATH because there may be executables for which we have only exec
|
||
* permissions, but not read (usually suid executables). */
|
||
fd = open(path, O_PATH|O_CLOEXEC);
|
||
if (fd < 0)
|
||
return -errno;
|
||
|
||
r = fd_verify_regular(fd);
|
||
if (r < 0)
|
||
return r;
|
||
|
||
r = access_fd(fd, X_OK);
|
||
if (r == -ENOSYS) {
|
||
/* /proc is not mounted. Fallback to access(). */
|
||
if (access(path, X_OK) < 0)
|
||
return -errno;
|
||
} else if (r < 0)
|
||
return r;
|
||
|
||
if (ret_fd)
|
||
*ret_fd = TAKE_FD(fd);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int find_executable_impl(const char *name, const char *root, char **ret_filename, int *ret_fd) {
|
||
_cleanup_close_ int fd = -1;
|
||
_cleanup_free_ char *path_name = NULL;
|
||
int r;
|
||
|
||
assert(name);
|
||
|
||
/* Function chase_symlinks() is invoked only when root is not NULL, as using it regardless of
|
||
* root value would alter the behavior of existing callers for example: /bin/sleep would become
|
||
* /usr/bin/sleep when find_executables is called. Hence, this function should be invoked when
|
||
* needed to avoid unforeseen regression or other complicated changes. */
|
||
if (root) {
|
||
r = chase_symlinks(name,
|
||
root,
|
||
CHASE_PREFIX_ROOT,
|
||
&path_name,
|
||
/* ret_fd= */ NULL); /* prefix root to name in case full paths are not specified */
|
||
if (r < 0)
|
||
return r;
|
||
|
||
name = path_name;
|
||
}
|
||
|
||
r = check_x_access(name, ret_fd ? &fd : NULL);
|
||
if (r < 0)
|
||
return r;
|
||
|
||
if (ret_filename) {
|
||
r = path_make_absolute_cwd(name, ret_filename);
|
||
if (r < 0)
|
||
return r;
|
||
}
|
||
|
||
if (ret_fd)
|
||
*ret_fd = TAKE_FD(fd);
|
||
|
||
return 0;
|
||
}
|
||
|
||
int find_executable_full(const char *name, const char *root, char **exec_search_path, bool use_path_envvar, char **ret_filename, int *ret_fd) {
|
||
int last_error = -ENOENT, r = 0;
|
||
const char *p = NULL;
|
||
|
||
assert(name);
|
||
|
||
if (is_path(name))
|
||
return find_executable_impl(name, root, ret_filename, ret_fd);
|
||
|
||
if (use_path_envvar)
|
||
/* 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;
|
||
|
||
if (exec_search_path) {
|
||
STRV_FOREACH(element, exec_search_path) {
|
||
_cleanup_free_ char *full_path = NULL;
|
||
|
||
if (!path_is_absolute(*element))
|
||
continue;
|
||
|
||
full_path = path_join(*element, name);
|
||
if (!full_path)
|
||
return -ENOMEM;
|
||
|
||
r = find_executable_impl(full_path, root, ret_filename, ret_fd);
|
||
if (r < 0) {
|
||
if (r != -EACCES)
|
||
last_error = r;
|
||
continue;
|
||
}
|
||
return 0;
|
||
}
|
||
return last_error;
|
||
}
|
||
|
||
/* Resolve a single-component name to a full path */
|
||
for (;;) {
|
||
_cleanup_free_ char *element = NULL;
|
||
|
||
r = extract_first_word(&p, &element, ":", EXTRACT_RELAX|EXTRACT_DONT_COALESCE_SEPARATORS);
|
||
if (r < 0)
|
||
return r;
|
||
if (r == 0)
|
||
break;
|
||
|
||
if (!path_is_absolute(element))
|
||
continue;
|
||
|
||
if (!path_extend(&element, name))
|
||
return -ENOMEM;
|
||
|
||
r = find_executable_impl(element, root, ret_filename, ret_fd);
|
||
if (r < 0) {
|
||
/* PATH entries which we don't have access to are ignored, as per tradition. */
|
||
if (r != -EACCES)
|
||
last_error = r;
|
||
continue;
|
||
}
|
||
|
||
/* Found it! */
|
||
return 0;
|
||
}
|
||
|
||
return last_error;
|
||
}
|
||
|
||
bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
|
||
bool changed = false, originally_unset;
|
||
|
||
assert(timestamp);
|
||
|
||
if (!paths)
|
||
return false;
|
||
|
||
originally_unset = *timestamp == 0;
|
||
|
||
STRV_FOREACH(i, paths) {
|
||
struct stat stats;
|
||
usec_t u;
|
||
|
||
if (stat(*i, &stats) < 0)
|
||
continue;
|
||
|
||
u = timespec_load(&stats.st_mtim);
|
||
|
||
/* check first */
|
||
if (*timestamp >= u)
|
||
continue;
|
||
|
||
log_debug(originally_unset ? "Loaded timestamp for '%s'." : "Timestamp of '%s' changed.", *i);
|
||
|
||
/* update timestamp */
|
||
if (update) {
|
||
*timestamp = u;
|
||
changed = true;
|
||
} else
|
||
return true;
|
||
}
|
||
|
||
return changed;
|
||
}
|
||
|
||
static int executable_is_good(const char *executable) {
|
||
_cleanup_free_ char *p = NULL, *d = NULL;
|
||
int r;
|
||
|
||
r = find_executable(executable, &p);
|
||
if (r == -ENOENT)
|
||
return 0;
|
||
if (r < 0)
|
||
return r;
|
||
|
||
/* An fsck that is linked to /bin/true is a non-existent fsck */
|
||
|
||
r = readlink_malloc(p, &d);
|
||
if (r == -EINVAL) /* not a symlink */
|
||
return 1;
|
||
if (r < 0)
|
||
return r;
|
||
|
||
return !PATH_IN_SET(d, "true"
|
||
"/bin/true",
|
||
"/usr/bin/true",
|
||
"/dev/null");
|
||
}
|
||
|
||
int fsck_exists(const char *fstype) {
|
||
const char *checker;
|
||
|
||
assert(fstype);
|
||
|
||
if (streq(fstype, "auto"))
|
||
return -EINVAL;
|
||
|
||
checker = strjoina("fsck.", fstype);
|
||
return executable_is_good(checker);
|
||
}
|
||
|
||
char* dirname_malloc(const char *path) {
|
||
char *d, *dir, *dir2;
|
||
|
||
assert(path);
|
||
|
||
d = strdup(path);
|
||
if (!d)
|
||
return NULL;
|
||
|
||
dir = dirname(d);
|
||
assert(dir);
|
||
|
||
if (dir == d)
|
||
return d;
|
||
|
||
dir2 = strdup(dir);
|
||
free(d);
|
||
|
||
return dir2;
|
||
}
|
||
#endif /* NM_IGNORED */
|
||
|
||
static const char *skip_slash_or_dot(const char *p) {
|
||
for (; !isempty(p); p++) {
|
||
if (*p == '/')
|
||
continue;
|
||
if (startswith(p, "./")) {
|
||
p++;
|
||
continue;
|
||
}
|
||
break;
|
||
}
|
||
return p;
|
||
}
|
||
|
||
int path_find_first_component(const char **p, bool accept_dot_dot, const char **ret) {
|
||
const char *q, *first, *end_first, *next;
|
||
size_t len;
|
||
|
||
assert(p);
|
||
|
||
/* When a path is input, then returns the pointer to the first component and its length, and
|
||
* move the input pointer to the next component or nul. This skips both over any '/'
|
||
* immediately *before* and *after* the first component before returning.
|
||
*
|
||
* Examples
|
||
* Input: p: "//.//aaa///bbbbb/cc"
|
||
* Output: p: "bbbbb///cc"
|
||
* ret: "aaa///bbbbb/cc"
|
||
* return value: 3 (== strlen("aaa"))
|
||
*
|
||
* Input: p: "aaa//"
|
||
* Output: p: (pointer to NUL)
|
||
* ret: "aaa//"
|
||
* return value: 3 (== strlen("aaa"))
|
||
*
|
||
* Input: p: "/", ".", ""
|
||
* Output: p: (pointer to NUL)
|
||
* ret: NULL
|
||
* return value: 0
|
||
*
|
||
* Input: p: NULL
|
||
* Output: p: NULL
|
||
* ret: NULL
|
||
* return value: 0
|
||
*
|
||
* Input: p: "(too long component)"
|
||
* Output: return value: -EINVAL
|
||
*
|
||
* (when accept_dot_dot is false)
|
||
* Input: p: "//..//aaa///bbbbb/cc"
|
||
* Output: return value: -EINVAL
|
||
*/
|
||
|
||
q = *p;
|
||
|
||
first = skip_slash_or_dot(q);
|
||
if (isempty(first)) {
|
||
*p = first;
|
||
if (ret)
|
||
*ret = NULL;
|
||
return 0;
|
||
}
|
||
if (streq(first, ".")) {
|
||
*p = first + 1;
|
||
if (ret)
|
||
*ret = NULL;
|
||
return 0;
|
||
}
|
||
|
||
end_first = strchrnul(first, '/');
|
||
len = end_first - first;
|
||
|
||
if (len > NAME_MAX)
|
||
return -EINVAL;
|
||
if (!accept_dot_dot && len == 2 && first[0] == '.' && first[1] == '.')
|
||
return -EINVAL;
|
||
|
||
next = skip_slash_or_dot(end_first);
|
||
|
||
*p = next + streq(next, ".");
|
||
if (ret)
|
||
*ret = first;
|
||
return len;
|
||
}
|
||
|
||
static const char *skip_slash_or_dot_backward(const char *path, const char *q) {
|
||
assert(path);
|
||
assert(!q || q >= path);
|
||
|
||
for (; q; q = PTR_SUB1(q, path)) {
|
||
if (*q == '/')
|
||
continue;
|
||
if (q > path && strneq(q - 1, "/.", 2))
|
||
continue;
|
||
break;
|
||
}
|
||
return q;
|
||
}
|
||
|
||
int path_find_last_component(const char *path, bool accept_dot_dot, const char **next, const char **ret) {
|
||
const char *q, *last_end, *last_begin;
|
||
size_t len;
|
||
|
||
/* Similar to path_find_first_component(), but search components from the end.
|
||
*
|
||
* Examples
|
||
* Input: path: "//.//aaa///bbbbb/cc//././"
|
||
* next: NULL
|
||
* Output: next: "/cc//././"
|
||
* ret: "cc//././"
|
||
* return value: 2 (== strlen("cc"))
|
||
*
|
||
* Input: path: "//.//aaa///bbbbb/cc//././"
|
||
* next: "/cc//././"
|
||
* Output: next: "///bbbbb/cc//././"
|
||
* ret: "bbbbb/cc//././"
|
||
* return value: 5 (== strlen("bbbbb"))
|
||
*
|
||
* Input: path: "/", ".", "", or NULL
|
||
* Output: next: equivalent to path
|
||
* ret: NULL
|
||
* return value: 0
|
||
*
|
||
* Input: path: "(too long component)"
|
||
* Output: return value: -EINVAL
|
||
*
|
||
* (when accept_dot_dot is false)
|
||
* Input: path: "//..//aaa///bbbbb/cc/..//"
|
||
* Output: return value: -EINVAL
|
||
*/
|
||
|
||
if (isempty(path)) {
|
||
if (next)
|
||
*next = path;
|
||
if (ret)
|
||
*ret = NULL;
|
||
return 0;
|
||
}
|
||
|
||
if (next && *next) {
|
||
if (*next < path || *next > path + strlen(path))
|
||
return -EINVAL;
|
||
if (*next == path) {
|
||
if (ret)
|
||
*ret = NULL;
|
||
return 0;
|
||
}
|
||
if (!IN_SET(**next, '\0', '/'))
|
||
return -EINVAL;
|
||
q = *next - 1;
|
||
} else
|
||
q = path + strlen(path) - 1;
|
||
|
||
q = skip_slash_or_dot_backward(path, q);
|
||
if (!q || /* the root directory */
|
||
(q == path && *q == '.')) { /* path is "." or "./" */
|
||
if (next)
|
||
*next = path;
|
||
if (ret)
|
||
*ret = NULL;
|
||
return 0;
|
||
}
|
||
|
||
last_end = q + 1;
|
||
|
||
while (q && *q != '/')
|
||
q = PTR_SUB1(q, path);
|
||
|
||
last_begin = q ? q + 1 : path;
|
||
len = last_end - last_begin;
|
||
|
||
if (len > NAME_MAX)
|
||
return -EINVAL;
|
||
if (!accept_dot_dot && len == 2 && strneq(last_begin, "..", 2))
|
||
return -EINVAL;
|
||
|
||
if (next) {
|
||
q = skip_slash_or_dot_backward(path, q);
|
||
*next = q ? q + 1 : path;
|
||
}
|
||
|
||
if (ret)
|
||
*ret = last_begin;
|
||
return len;
|
||
}
|
||
|
||
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.
|
||
*
|
||
* This always succeeds (except if you pass NULL in which case it returns NULL, too).
|
||
*/
|
||
|
||
unsigned l, k;
|
||
|
||
if (!path)
|
||
return NULL;
|
||
|
||
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;
|
||
}
|
||
|
||
int path_extract_filename(const char *path, char **ret) {
|
||
_cleanup_free_ char *a = NULL;
|
||
const char *c, *next = NULL;
|
||
int r;
|
||
|
||
/* Extracts the filename part (i.e. right-most component) from a path, i.e. string that passes
|
||
* filename_is_valid(). A wrapper around last_path_component(), but eats up trailing
|
||
* slashes. Returns:
|
||
*
|
||
* -EINVAL → if the path is not valid
|
||
* -EADDRNOTAVAIL → if only a directory was specified, but no filename, i.e. the root dir
|
||
* itself or "." is specified
|
||
* -ENOMEM → no memory
|
||
*
|
||
* Returns >= 0 on success. If the input path has a trailing slash, returns O_DIRECTORY, to
|
||
* indicate the referenced file must be a directory.
|
||
*
|
||
* This function guarantees to return a fully valid filename, i.e. one that passes
|
||
* filename_is_valid() – this means "." and ".." are not accepted. */
|
||
|
||
if (!path_is_valid(path))
|
||
return -EINVAL;
|
||
|
||
r = path_find_last_component(path, false, &next, &c);
|
||
if (r < 0)
|
||
return r;
|
||
if (r == 0) /* root directory */
|
||
return -EADDRNOTAVAIL;
|
||
|
||
a = strndup(c, r);
|
||
if (!a)
|
||
return -ENOMEM;
|
||
|
||
*ret = TAKE_PTR(a);
|
||
return strlen(c) > (size_t) r ? O_DIRECTORY : 0;
|
||
}
|
||
|
||
int path_extract_directory(const char *path, char **ret) {
|
||
_cleanup_free_ char *a = NULL;
|
||
const char *c, *next = NULL;
|
||
int r;
|
||
|
||
/* The inverse of path_extract_filename(), i.e. returns the directory path prefix. Returns:
|
||
*
|
||
* -EINVAL → if the path is not valid
|
||
* -EDESTADDRREQ → if no directory was specified in the passed in path, i.e. only a filename was passed
|
||
* -EADDRNOTAVAIL → if the passed in parameter had no filename but did have a directory, i.e.
|
||
* the root dir itself or "." was specified
|
||
* -ENOMEM → no memory (surprise!)
|
||
*
|
||
* This function guarantees to return a fully valid path, i.e. one that passes path_is_valid().
|
||
*/
|
||
|
||
r = path_find_last_component(path, false, &next, &c);
|
||
if (r < 0)
|
||
return r;
|
||
if (r == 0) /* empty or root */
|
||
return isempty(path) ? -EINVAL : -EADDRNOTAVAIL;
|
||
if (next == path) {
|
||
if (*path != '/') /* filename only */
|
||
return -EDESTADDRREQ;
|
||
|
||
a = strdup("/");
|
||
if (!a)
|
||
return -ENOMEM;
|
||
*ret = TAKE_PTR(a);
|
||
return 0;
|
||
}
|
||
|
||
a = strndup(path, next - path);
|
||
if (!a)
|
||
return -ENOMEM;
|
||
|
||
path_simplify(a);
|
||
|
||
if (!path_is_valid(a))
|
||
return -EINVAL;
|
||
|
||
*ret = TAKE_PTR(a);
|
||
return 0;
|
||
}
|
||
|
||
bool filename_is_valid(const char *p) {
|
||
const char *e;
|
||
|
||
if (isempty(p))
|
||
return false;
|
||
|
||
if (dot_or_dot_dot(p)) /* Yes, in this context we consider "." and ".." invalid */
|
||
return false;
|
||
|
||
e = strchrnul(p, '/');
|
||
if (*e != 0)
|
||
return false;
|
||
|
||
if (e - p > NAME_MAX) /* NAME_MAX is counted *without* the trailing NUL byte */
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
bool path_is_valid_full(const char *p, bool accept_dot_dot) {
|
||
if (isempty(p))
|
||
return false;
|
||
|
||
for (const char *e = p;;) {
|
||
int r;
|
||
|
||
r = path_find_first_component(&e, accept_dot_dot, NULL);
|
||
if (r < 0)
|
||
return false;
|
||
|
||
if (e - p >= PATH_MAX) /* Already reached the maximum length for a path? (PATH_MAX is counted
|
||
* *with* the trailing NUL byte) */
|
||
return false;
|
||
if (*e == 0) /* End of string? Yay! */
|
||
return true;
|
||
}
|
||
}
|
||
|
||
bool path_is_normalized(const char *p) {
|
||
if (!path_is_safe(p))
|
||
return false;
|
||
|
||
if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
|
||
return false;
|
||
|
||
if (strstr(p, "//"))
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
#if 0 /* NM_IGNORED */
|
||
char *file_in_same_dir(const char *path, const char *filename) {
|
||
char *e, *ret;
|
||
size_t k;
|
||
|
||
assert(path);
|
||
assert(filename);
|
||
|
||
/* This removes the last component of path and appends
|
||
* filename, unless the latter is absolute anyway or the
|
||
* former isn't */
|
||
|
||
if (path_is_absolute(filename))
|
||
return strdup(filename);
|
||
|
||
e = strrchr(path, '/');
|
||
if (!e)
|
||
return strdup(filename);
|
||
|
||
k = strlen(filename);
|
||
ret = new(char, (e + 1 - path) + k + 1);
|
||
if (!ret)
|
||
return NULL;
|
||
|
||
memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
|
||
return ret;
|
||
}
|
||
|
||
bool hidden_or_backup_file(const char *filename) {
|
||
assert(filename);
|
||
|
||
if (filename[0] == '.' ||
|
||
STR_IN_SET(filename,
|
||
"lost+found",
|
||
"aquota.user",
|
||
"aquota.group") ||
|
||
endswith(filename, "~"))
|
||
return true;
|
||
|
||
const char *dot = strrchr(filename, '.');
|
||
if (!dot)
|
||
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(dot + 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");
|
||
}
|
||
|
||
bool is_device_path(const char *path) {
|
||
|
||
/* Returns true for 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 those accepted by
|
||
* DeviceAllow= and DeviceDeny=. */
|
||
|
||
if (STARTSWITH_SET(path, "block-", "char-"))
|
||
return true;
|
||
|
||
return valid_device_node_path(path);
|
||
}
|
||
#endif /* NM_IGNORED */
|
||
|
||
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;
|
||
}
|
||
|
||
#if 0 /* NM_IGNORED */
|
||
bool empty_or_root(const char *path) {
|
||
|
||
/* 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 (isempty(path))
|
||
return true;
|
||
|
||
return path_equal(path, "/");
|
||
}
|
||
|
||
bool path_strv_contains(char **l, const char *path) {
|
||
STRV_FOREACH(i, l)
|
||
if (path_equal(*i, path))
|
||
return true;
|
||
|
||
return false;
|
||
}
|
||
|
||
bool prefixed_path_strv_contains(char **l, const char *path) {
|
||
STRV_FOREACH(i, l) {
|
||
const char *j = *i;
|
||
|
||
if (*j == '-')
|
||
j++;
|
||
if (*j == '+')
|
||
j++;
|
||
if (path_equal(j, path))
|
||
return true;
|
||
}
|
||
|
||
return false;
|
||
}
|
||
#endif /* NM_IGNORED */
|