projects / thirdparty / systemd.git / blame
| Commit | Line | Data |
|---|---|---|
| 53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
| c8b3094d LP |
2 | /*** |
| 3 | This file is part of systemd. | |
| 4 | ||
| 5 | Copyright 2010 Lennart Poettering | |
| 6 | ||
| 7 | systemd is free software; you can redistribute it and/or modify it | |
| 8 | under the terms of the GNU Lesser General Public License as published by | |
| 9 | the Free Software Foundation; either version 2.1 of the License, or | |
| 10 | (at your option) any later version. | |
| 11 | ||
| 12 | systemd is distributed in the hope that it will be useful, but | |
| 13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 15 | Lesser General Public License for more details. | |
| 16 | ||
| 17 | You should have received a copy of the GNU Lesser General Public License | |
| 18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
| 19 | ***/ | |
| 20 | ||
| 11c3a366 TA |
21 | #include <errno.h> |
| 22 | #include <fcntl.h> | |
| c8b3094d LP |
23 | #include <sys/ioctl.h> |
| 24 | #include <sys/stat.h> | |
| 25 | #include <linux/fs.h> | |
| 26 | ||
| 27 | #include "chattr-util.h" | |
| 28 | #include "fd-util.h" | |
| 11c3a366 | 29 | #include "macro.h" |
| c8b3094d LP |
30 | |
| 31 | int chattr_fd(int fd, unsigned value, unsigned mask) { | |
| 32 | unsigned old_attr, new_attr; | |
| 33 | struct stat st; | |
| 34 | ||
| 35 | assert(fd >= 0); | |
| 36 | ||
| 37 | if (fstat(fd, &st) < 0) | |
| 38 | return -errno; | |
| 39 | ||
| 40 | /* Explicitly check whether this is a regular file or | |
| 41 | * directory. If it is anything else (such as a device node or | |
| 42 | * fifo), then the ioctl will not hit the file systems but | |
| 43 | * possibly drivers, where the ioctl might have different | |
| 44 | * effects. Notably, DRM is using the same ioctl() number. */ | |
| 45 | ||
| 46 | if (!S_ISDIR(st.st_mode) && !S_ISREG(st.st_mode)) | |
| 47 | return -ENOTTY; | |
| 48 | ||
| 49 | if (mask == 0) | |
| 50 | return 0; | |
| 51 | ||
| 52 | if (ioctl(fd, FS_IOC_GETFLAGS, &old_attr) < 0) | |
| 53 | return -errno; | |
| 54 | ||
| 55 | new_attr = (old_attr & ~mask) | (value & mask); | |
| 56 | if (new_attr == old_attr) | |
| 57 | return 0; | |
| 58 | ||
| 59 | if (ioctl(fd, FS_IOC_SETFLAGS, &new_attr) < 0) | |
| 60 | return -errno; | |
| 61 | ||
| 62 | return 1; | |
| 63 | } | |
| 64 | ||
| 65 | int chattr_path(const char *p, unsigned value, unsigned mask) { | |
| 66 | _cleanup_close_ int fd = -1; | |
| 67 | ||
| 68 | assert(p); | |
| 69 | ||
| 70 | if (mask == 0) | |
| 71 | return 0; | |
| 72 | ||
| 73 | fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); | |
| 74 | if (fd < 0) | |
| 75 | return -errno; | |
| 76 | ||
| 77 | return chattr_fd(fd, value, mask); | |
| 78 | } | |
| 79 | ||
| 80 | int read_attr_fd(int fd, unsigned *ret) { | |
| 81 | struct stat st; | |
| 82 | ||
| 83 | assert(fd >= 0); | |
| 84 | ||
| 85 | if (fstat(fd, &st) < 0) | |
| 86 | return -errno; | |
| 87 | ||
| 88 | if (!S_ISDIR(st.st_mode) && !S_ISREG(st.st_mode)) | |
| 89 | return -ENOTTY; | |
| 90 | ||
| 91 | if (ioctl(fd, FS_IOC_GETFLAGS, ret) < 0) | |
| 92 | return -errno; | |
| 93 | ||
| 94 | return 0; | |
| 95 | } | |
| 96 | ||
| 97 | int read_attr_path(const char *p, unsigned *ret) { | |
| 98 | _cleanup_close_ int fd = -1; | |
| 99 | ||
| 100 | assert(p); | |
| 101 | assert(ret); | |
| 102 | ||
| 103 | fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); | |
| 104 | if (fd < 0) | |
| 105 | return -errno; | |
| 106 | ||
| 107 | return read_attr_fd(fd, ret); | |
| 108 | } |