static int node_fixup(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid) { struct udev *udev = udev_device_get_udev(dev); const char *devnode = udev_device_get_devnode(dev); dev_t devnum = udev_device_get_devnum(dev); struct stat stats; int err = 0; if (strcmp(udev_device_get_subsystem(dev), "block") == 0) mode |= S_IFBLK; else mode |= S_IFCHR; if (lstat(devnode, &stats) != 0) { err = -errno; info(udev, "can not stat() node '%s' (%m)\n", devnode); goto out; } if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) || (stats.st_rdev != devnum)) { err = -EEXIST; info(udev, "found node '%s' with non-matching devnum %s, skip handling\n", udev_device_get_devnode(dev), udev_device_get_id_filename(dev)); goto out; } if ((stats.st_mode & 0777) != (mode & 0777) || stats.st_uid != uid || stats.st_gid != gid) { info(udev, "set permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); chmod(devnode, mode); chown(devnode, uid, gid); } else { info(udev, "preserve permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); } /* * Set initial selinux file context only on add events. * We set the proper context on bootup (triger) or for newly * added devices, but we don't change it later, in case * something else has set a custom context in the meantime. */ if (strcmp(udev_device_get_action(dev), "add") == 0) udev_selinux_lsetfilecon(udev, devnode, mode); /* always update timestamp when we re-use the node, like on media change events */ utimensat(AT_FDCWD, devnode, NULL, 0); out: return err; }
static int node_symlink(struct udev *udev, const char *node, const char *slink) { struct stat stats; char target[UTIL_PATH_SIZE]; char *s; size_t l; char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; int i = 0; int tail = 0; int err = 0; /* use relative link */ target[0] = '\0'; while (node[i] && (node[i] == slink[i])) { if (node[i] == '/') tail = i+1; i++; } s = target; l = sizeof(target); while (slink[i] != '\0') { if (slink[i] == '/') l = util_strpcpy(&s, l, "../"); i++; } l = util_strscpy(s, l, &node[tail]); if (l == 0) { err = -EINVAL; goto exit; } /* preserve link with correct target, do not replace node of other device */ if (lstat(slink, &stats) == 0) { if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) { struct stat stats2; info(udev, "found existing node instead of symlink '%s'\n", slink); if (lstat(node, &stats2) == 0) { if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) && stats.st_rdev == stats2.st_rdev && stats.st_ino != stats2.st_ino) { info(udev, "replace device node '%s' with symlink to our node '%s'\n", slink, node); } else { err(udev, "device node '%s' already exists, " "link to '%s' will not overwrite it\n", slink, node); goto exit; } } } else if (S_ISLNK(stats.st_mode)) { char buf[UTIL_PATH_SIZE]; int len; dbg(udev, "found existing symlink '%s'\n", slink); len = readlink(slink, buf, sizeof(buf)); if (len > 0 && len < (int)sizeof(buf)) { buf[len] = '\0'; if (strcmp(target, buf) == 0) { info(udev, "preserve already existing symlink '%s' to '%s'\n", slink, target); udev_selinux_lsetfilecon(udev, slink, S_IFLNK); utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW); goto exit; } } } } else { info(udev, "creating symlink '%s' to '%s'\n", slink, target); do { err = util_create_path_selinux(udev, slink); if (err != 0 && err != -ENOENT) break; udev_selinux_setfscreatecon(udev, slink, S_IFLNK); err = symlink(target, slink); if (err != 0) err = -errno; udev_selinux_resetfscreatecon(udev); } while (err == -ENOENT); if (err == 0) goto exit; } info(udev, "atomically replace '%s'\n", slink); util_strscpyl(slink_tmp, sizeof(slink_tmp), slink, TMP_FILE_EXT, NULL); unlink(slink_tmp); do { err = util_create_path_selinux(udev, slink_tmp); if (err != 0 && err != -ENOENT) break; udev_selinux_setfscreatecon(udev, slink_tmp, S_IFLNK); err = symlink(target, slink_tmp); if (err != 0) err = -errno; udev_selinux_resetfscreatecon(udev); } while (err == -ENOENT); if (err != 0) { err(udev, "symlink '%s' '%s' failed: %m\n", target, slink_tmp); goto exit; } err = rename(slink_tmp, slink); if (err != 0) { err(udev, "rename '%s' '%s' failed: %m\n", slink_tmp, slink); unlink(slink_tmp); } exit: return err; }
static int node_symlink(struct udev *udev, const char *node, const char *slink) { struct stat stats; char target[UTIL_PATH_SIZE]; char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; int i = 0; int tail = 0; int len; int err = 0; /* use relative link */ target[0] = '\0'; while (node[i] && (node[i] == slink[i])) { if (node[i] == '/') tail = i+1; i++; } while (slink[i] != '\0') { if (slink[i] == '/') util_strlcat(target, "../", sizeof(target)); i++; } util_strlcat(target, &node[tail], sizeof(target)); /* preserve link with correct target, do not replace node of other device */ if (lstat(slink, &stats) == 0) { if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) { struct stat stats2; info(udev, "found existing node instead of symlink '%s'\n", slink); if (lstat(node, &stats2) == 0) { if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) && stats.st_rdev == stats2.st_rdev) { info(udev, "replace device node '%s' with symlink to our node '%s'\n", slink, node); } else { err(udev, "device node '%s' already exists, " "link to '%s' will not overwrite it\n", slink, node); goto exit; } } } else if (S_ISLNK(stats.st_mode)) { char buf[UTIL_PATH_SIZE]; dbg(udev, "found existing symlink '%s'\n", slink); len = readlink(slink, buf, sizeof(buf)); if (len > 0) { buf[len] = '\0'; if (strcmp(target, buf) == 0) { info(udev, "preserve already existing symlink '%s' to '%s'\n", slink, target); udev_selinux_lsetfilecon(udev, slink, S_IFLNK); goto exit; } } } } else { info(udev, "creating symlink '%s' to '%s'\n", slink, target); udev_selinux_setfscreatecon(udev, slink, S_IFLNK); err = symlink(target, slink); udev_selinux_resetfscreatecon(udev); if (err == 0) goto exit; } info(udev, "atomically replace '%s'\n", slink); util_strlcpy(slink_tmp, slink, sizeof(slink_tmp)); util_strlcat(slink_tmp, TMP_FILE_EXT, sizeof(slink_tmp)); unlink(slink_tmp); udev_selinux_setfscreatecon(udev, slink, S_IFLNK); err = symlink(target, slink_tmp); udev_selinux_resetfscreatecon(udev); if (err != 0) { err(udev, "symlink(%s, %s) failed: %m\n", target, slink_tmp); goto exit; } err = rename(slink_tmp, slink); if (err != 0) { err(udev, "rename(%s, %s) failed: %m\n", slink_tmp, slink); unlink(slink_tmp); goto exit; } exit: return err; }
int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mode_t mode, uid_t uid, gid_t gid) { struct udev *udev = udev_device_get_udev(dev); char file_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; struct stat stats; int preserve = 0; int err = 0; if (major(devnum) == 0) devnum = udev_device_get_devnum(dev); if (strcmp(udev_device_get_subsystem(dev), "block") == 0) mode |= S_IFBLK; else mode |= S_IFCHR; if (file == NULL) file = udev_device_get_devnode(dev); if (lstat(file, &stats) == 0) { if (((stats.st_mode & S_IFMT) == (mode & S_IFMT)) && (stats.st_rdev == devnum)) { info(udev, "preserve file '%s', because it has correct dev_t\n", file); preserve = 1; udev_selinux_lsetfilecon(udev, file, mode); } else { info(udev, "atomically replace existing file '%s'\n", file); util_strlcpy(file_tmp, file, sizeof(file_tmp)); util_strlcat(file_tmp, TMP_FILE_EXT, sizeof(file_tmp)); unlink(file_tmp); udev_selinux_setfscreatecon(udev, file_tmp, mode); err = mknod(file_tmp, mode, devnum); udev_selinux_resetfscreatecon(udev); if (err != 0) { err(udev, "mknod(%s, %#o, %u, %u) failed: %m\n", file_tmp, mode, major(devnum), minor(devnum)); goto exit; } err = rename(file_tmp, file); if (err != 0) { err(udev, "rename(%s, %s) failed: %m\n", file_tmp, file); unlink(file_tmp); } } } else { info(udev, "mknod(%s, %#o, (%u,%u))\n", file, mode, major(devnum), minor(devnum)); udev_selinux_setfscreatecon(udev, file, mode); err = mknod(file, mode, devnum); udev_selinux_resetfscreatecon(udev); if (err != 0) { err(udev, "mknod(%s, %#o, (%u,%u) failed: %m\n", file, mode, major(devnum), minor(devnum)); goto exit; } } if (!preserve || stats.st_mode != mode) { info(udev, "chmod(%s, %#o)\n", file, mode); err = chmod(file, mode); if (err != 0) { err(udev, "chmod(%s, %#o) failed: %m\n", file, mode); goto exit; } } if (!preserve || stats.st_uid != uid || stats.st_gid != gid) { info(udev, "chown(%s, %u, %u)\n", file, uid, gid); err = chown(file, uid, gid); if (err != 0) { err(udev, "chown(%s, %u, %u) failed: %m\n", file, uid, gid); goto exit; } } exit: return err; }
int udev_node_mknod(struct udev_device *dev, const char *file, mode_t mode, uid_t uid, gid_t gid) { struct udev *udev = udev_device_get_udev(dev); dev_t devnum = udev_device_get_devnum(dev); struct stat stats; int err = 0; if (strcmp(udev_device_get_subsystem(dev), "block") == 0) mode |= S_IFBLK; else mode |= S_IFCHR; if (file == NULL) file = udev_device_get_devnode(dev); if (lstat(file, &stats) == 0) { if (((stats.st_mode & S_IFMT) == (mode & S_IFMT)) && (stats.st_rdev == devnum)) { info(udev, "preserve file '%s', because it has correct dev_t\n", file); if (stats.st_mode != mode || stats.st_uid != uid || stats.st_gid != gid) { info(udev, "set permissions %s, %#o, uid=%u, gid=%u\n", file, mode, uid, gid); chmod(file, mode); chown(file, uid, gid); } else { info(udev, "preserve permissions %s, %#o, uid=%u, gid=%u\n", file, mode, uid, gid); } /* * Set initial selinux file context only on add events. * We set the proper context on bootup (triger) or for newly * added devices, but we don't change it later, in case * something else has set a custom context in the meantime. */ if (strcmp(udev_device_get_action(dev), "add") == 0) udev_selinux_lsetfilecon(udev, file, mode); /* always update timestamp when we re-use the node, like on media change events */ utimensat(AT_FDCWD, file, NULL, 0); } else { char file_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; info(udev, "atomically replace existing file '%s'\n", file); util_strscpyl(file_tmp, sizeof(file_tmp), file, TMP_FILE_EXT, NULL); unlink(file_tmp); udev_selinux_setfscreatecon(udev, file_tmp, mode); err = mknod(file_tmp, mode, devnum); udev_selinux_resetfscreatecon(udev); if (err != 0) { err(udev, "mknod '%s' %u:%u %#o failed: %m\n", file_tmp, major(devnum), minor(devnum), mode); goto exit; } err = rename(file_tmp, file); if (err != 0) { err(udev, "rename '%s' '%s' failed: %m\n", file_tmp, file); unlink(file_tmp); goto exit; } info(udev, "set permissions '%s' %#o uid=%u gid=%u\n", file, mode, uid, gid); chmod(file, mode); chown(file, uid, gid); } } else { info(udev, "mknod '%s' %u:%u %#o\n", file, major(devnum), minor(devnum), mode); do { err = util_create_path(udev, file); if (err != 0 && err != -ENOENT) break; udev_selinux_setfscreatecon(udev, file, mode); err = mknod(file, mode, devnum); if (err != 0) err = -errno; udev_selinux_resetfscreatecon(udev); } while (err == -ENOENT); if (err != 0) err(udev, "mknod '%s' %u:%u %#o' failed: %m\n", file, major(devnum), minor(devnum), mode); info(udev, "set permissions '%s' %#o uid=%u gid=%u\n", file, mode, uid, gid); chmod(file, mode); chown(file, uid, gid); } exit: return err; }