aboutsummaryrefslogtreecommitdiff
path: root/src/rc
diff options
context:
space:
mode:
Diffstat (limited to 'src/rc')
-rw-r--r--src/rc/checkpath.c103
1 files changed, 96 insertions, 7 deletions
diff --git a/src/rc/checkpath.c b/src/rc/checkpath.c
index 448c9cf8..ff54a892 100644
--- a/src/rc/checkpath.c
+++ b/src/rc/checkpath.c
@@ -16,6 +16,7 @@
* except according to the terms contained in the LICENSE file.
*/
+#define _GNU_SOURCE
#include <sys/types.h>
#include <sys/stat.h>
@@ -23,6 +24,7 @@
#include <fcntl.h>
#include <getopt.h>
#include <grp.h>
+#include <libgen.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
@@ -44,7 +46,7 @@ typedef enum {
const char *applet = NULL;
const char *extraopts ="path1 [path2] [...]";
-const char *getoptstring = "dDfFpm:o:W" getoptstring_COMMON;
+const char *getoptstring = "dDfFpm:o:sW" getoptstring_COMMON;
const struct option longopts[] = {
{ "directory", 0, NULL, 'd'},
{ "directory-truncate", 0, NULL, 'D'},
@@ -53,6 +55,7 @@ const struct option longopts[] = {
{ "pipe", 0, NULL, 'p'},
{ "mode", 1, NULL, 'm'},
{ "owner", 1, NULL, 'o'},
+ { "symlinks", 0, NULL, 's'},
{ "writable", 0, NULL, 'W'},
longopts_COMMON
};
@@ -64,15 +67,92 @@ const char * const longopts_help[] = {
"Create a named pipe (FIFO) if not exists",
"Mode to check",
"Owner to check (user:group)",
+ "follow symbolic links (irrelivent on linux)",
"Check whether the path is writable or not",
longopts_help_COMMON
};
const char *usagestring = NULL;
+static int get_dirfd(char *path, bool symlinks) {
+ char *ch;
+ char *item;
+ char *linkpath = NULL;
+ char *path_dupe;
+ char *str;
+ int components = 0;
+ int dirfd;
+ int flags = 0;
+ int new_dirfd;
+ struct stat st;
+ ssize_t linksize;
+
+ if (!path || *path != '/')
+ eerrorx("%s: empty or relative path", applet);
+ dirfd = openat(dirfd, "/", O_RDONLY);
+ if (dirfd == -1)
+ eerrorx("%s: unable to open the root directory: %s",
+ applet, strerror(errno));
+ path_dupe = xstrdup(path);
+ ch = path_dupe;
+ while (*ch) {
+ if (*ch == '/')
+ components++;
+ ch++;
+ }
+ item = strtok(path_dupe, "/");
+#ifdef O_PATH
+ flags |= O_PATH;
+#endif
+ if (!symlinks)
+ flags |= O_NOFOLLOW;
+ flags |= O_RDONLY;
+ while (dirfd > 0 && item && components > 1) {
+ str = xstrdup(linkpath ? linkpath : item);
+ new_dirfd = openat(dirfd, str, flags);
+ if (new_dirfd == -1)
+ eerrorx("%s: %s: could not open %s: %s", applet, path, str,
+ strerror(errno));
+ if (fstat(new_dirfd, &st) == -1)
+ eerrorx("%s: %s: unable to stat %s: %s", applet, path, item,
+ strerror(errno));
+ if (S_ISLNK(st.st_mode) ) {
+ if (st.st_uid != 0)
+ eerrorx("%s: %s: synbolic link %s not owned by root",
+ applet, path, str);
+ linksize = st.st_size+1;
+ if (linkpath)
+ free(linkpath);
+ linkpath = xmalloc(linksize);
+ memset(linkpath, 0, linksize);
+ if (readlinkat(new_dirfd, "", linkpath, linksize) != st.st_size)
+ eerrorx("%s: symbolic link destination changed", applet);
+ /*
+ * now follow the symlink.
+ */
+ close(new_dirfd);
+ } else {
+ close(dirfd);
+ dirfd = new_dirfd;
+ free(linkpath);
+ linkpath = NULL;
+ item = strtok(NULL, "/");
+ components--;
+ }
+ }
+ free(path_dupe);
+ if (linkpath) {
+ free(linkpath);
+ linkpath = NULL;
+ }
+ return dirfd;
+}
+
static int do_check(char *path, uid_t uid, gid_t gid, mode_t mode,
- inode_t type, bool trunc, bool chowner, bool selinux_on)
+ inode_t type, bool trunc, bool chowner, bool symlinks, bool selinux_on)
{
struct stat st;
+ char *name = NULL;
+ int dirfd;
int fd;
int flags;
int r;
@@ -93,14 +173,16 @@ static int do_check(char *path, uid_t uid, gid_t gid, mode_t mode,
#endif
if (trunc)
flags |= O_TRUNC;
- readfd = open(path, readflags);
+ xasprintf(&name, "%s", basename_c(path));
+ dirfd = get_dirfd(path, symlinks);
+ readfd = openat(dirfd, name, readflags);
if (readfd == -1 || (type == inode_file && trunc)) {
if (type == inode_file) {
einfo("%s: creating file", path);
if (!mode) /* 664 */
mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH;
u = umask(0);
- fd = open(path, flags, mode);
+ fd = openat(dirfd, name, flags, mode);
umask(u);
if (fd == -1) {
eerror("%s: open: %s", applet, strerror(errno));
@@ -122,7 +204,7 @@ static int do_check(char *path, uid_t uid, gid_t gid, mode_t mode,
strerror (errno));
return -1;
}
- readfd = open(path, readflags);
+ readfd = openat(dirfd, name, readflags);
if (readfd == -1) {
eerror("%s: unable to open directory: %s", applet,
strerror(errno));
@@ -140,7 +222,7 @@ static int do_check(char *path, uid_t uid, gid_t gid, mode_t mode,
strerror (errno));
return -1;
}
- readfd = open(path, readflags);
+ readfd = openat(dirfd, name, readflags);
if (readfd == -1) {
eerror("%s: unable to open fifo: %s", applet,
strerror(errno));
@@ -259,6 +341,7 @@ int main(int argc, char **argv)
int retval = EXIT_SUCCESS;
bool trunc = false;
bool chowner = false;
+ bool symlinks = false;
bool writable = false;
bool selinux_on = false;
@@ -293,6 +376,11 @@ int main(int argc, char **argv)
eerrorx("%s: owner `%s' not found",
applet, optarg);
break;
+ case 's':
+#ifndef O_PATH
+ symlinks = true;
+#endif
+ break;
case 'W':
writable = true;
break;
@@ -320,7 +408,8 @@ int main(int argc, char **argv)
while (optind < argc) {
if (writable)
exit(!is_writable(argv[optind]));
- if (do_check(argv[optind], uid, gid, mode, type, trunc, chowner, selinux_on))
+ if (do_check(argv[optind], uid, gid, mode, type, trunc, chowner,
+ symlinks, selinux_on))
retval = EXIT_FAILURE;
optind++;
}