diff options
Diffstat (limited to 'lib/chowndir.c')
| -rw-r--r-- | lib/chowndir.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/lib/chowndir.c b/lib/chowndir.c new file mode 100644 index 0000000..d31618a --- /dev/null +++ b/lib/chowndir.c @@ -0,0 +1,146 @@ +/* + * SPDX-FileCopyrightText: 1992 - 1993, Julianne Frances Haugh + * SPDX-FileCopyrightText: 1996 - 2000, Marek Michałkiewicz + * SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko + * SPDX-FileCopyrightText: 2010 - , Nicolas François + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <config.h> + +#ident "$Id$" + +#include <sys/types.h> +#include <sys/stat.h> +#include "prototypes.h" +#include "defines.h" +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> + +static int chown_tree_at (int at_fd, + const char *path, + uid_t old_uid, + uid_t new_uid, + gid_t old_gid, + gid_t new_gid) +{ + DIR *dir; + const struct dirent *ent; + struct stat dir_sb; + int dir_fd, rc = 0; + + dir_fd = openat (at_fd, path, O_RDONLY | O_DIRECTORY | O_NOFOLLOW | O_CLOEXEC); + if (dir_fd < 0) { + return -1; + } + + dir = fdopendir (dir_fd); + if (!dir) { + (void) close (dir_fd); + return -1; + } + + /* + * Open the directory and read each entry. Every entry is tested + * to see if it is a directory, and if so this routine is called + * recursively. If not, it is checked to see if an ownership + * shall be changed. + */ + while ((ent = readdir (dir))) { + uid_t tmpuid = (uid_t) -1; + gid_t tmpgid = (gid_t) -1; + struct stat ent_sb; + + /* + * Skip the "." and ".." entries + */ + if ( (strcmp (ent->d_name, ".") == 0) + || (strcmp (ent->d_name, "..") == 0)) { + continue; + } + + rc = fstatat (dirfd(dir), ent->d_name, &ent_sb, AT_SYMLINK_NOFOLLOW); + if (rc < 0) { + break; + } + + if (S_ISDIR (ent_sb.st_mode)) { + /* + * Do the entire subdirectory. + */ + rc = chown_tree_at (dirfd(dir), ent->d_name, old_uid, new_uid, old_gid, new_gid); + if (0 != rc) { + break; + } + } + + /* + * By default, the IDs are not changed (-1). + * + * If the file is not owned by the user, the owner is not + * changed. + * + * If the file is not group-owned by the group, the + * group-owner is not changed. + */ + if (((uid_t) -1 == old_uid) || (ent_sb.st_uid == old_uid)) { + tmpuid = new_uid; + } + if (((gid_t) -1 == old_gid) || (ent_sb.st_gid == old_gid)) { + tmpgid = new_gid; + } + if (((uid_t) -1 != tmpuid) || ((gid_t) -1 != tmpgid)) { + rc = fchownat (dirfd(dir), ent->d_name, tmpuid, tmpgid, AT_SYMLINK_NOFOLLOW); + if (0 != rc) { + break; + } + } + } + + /* + * Now do the root of the tree + */ + if ((0 == rc) && (fstat (dirfd(dir), &dir_sb) == 0)) { + uid_t tmpuid = (uid_t) -1; + gid_t tmpgid = (gid_t) -1; + if (((uid_t) -1 == old_uid) || (dir_sb.st_uid == old_uid)) { + tmpuid = new_uid; + } + if (((gid_t) -1 == old_gid) || (dir_sb.st_gid == old_gid)) { + tmpgid = new_gid; + } + if (((uid_t) -1 != tmpuid) || ((gid_t) -1 != tmpgid)) { + rc = fchown (dirfd(dir), tmpuid, tmpgid); + } + } else { + rc = -1; + } + + (void) closedir (dir); + + return rc; +} + +/* + * chown_tree - change ownership of files in a directory tree + * + * chown_dir() walks a directory tree and changes the ownership + * of all files owned by the provided user ID. + * + * Only files owned (resp. group-owned) by old_uid (resp. by old_gid) + * will have their ownership (resp. group-ownership) modified, unless + * old_uid (resp. old_gid) is set to -1. + * + * new_uid and new_gid can be set to -1 to indicate that no owner or + * group-owner shall be changed. + */ +int chown_tree (const char *root, + uid_t old_uid, + uid_t new_uid, + gid_t old_gid, + gid_t new_gid) +{ + return chown_tree_at (AT_FDCWD, root, old_uid, new_uid, old_gid, new_gid); +} |