-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
/***
- This file is part of systemd.
-
- Copyright 2013 Intel Corporation
+ Copyright © 2013 Intel Corporation
Author: Auke Kok <auke-jan.h.kok@intel.com>
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
#include <sys/xattr.h>
+#include <unistd.h>
-#include "util.h"
-#include "process-util.h"
-#include "path-util.h"
+#include "alloc-util.h"
+#include "fd-util.h"
#include "fileio.h"
+#include "log.h"
+#include "macro.h"
+#include "path-util.h"
+#include "process-util.h"
#include "smack-util.h"
+#include "stdio-util.h"
+#include "string-table.h"
+#include "xattr-util.h"
-#define SMACK_FLOOR_LABEL "_"
-#define SMACK_STAR_LABEL "*"
-
+#if ENABLE_SMACK
bool mac_smack_use(void) {
-#ifdef HAVE_SMACK
static int cached_use = -1;
if (cached_use < 0)
cached_use = access("/sys/fs/smackfs/", F_OK) >= 0;
return cached_use;
-#else
- return false;
-#endif
}
-int mac_smack_apply(const char *path, const char *label) {
- int r = 0;
+static const char* const smack_attr_table[_SMACK_ATTR_MAX] = {
+ [SMACK_ATTR_ACCESS] = "security.SMACK64",
+ [SMACK_ATTR_EXEC] = "security.SMACK64EXEC",
+ [SMACK_ATTR_MMAP] = "security.SMACK64MMAP",
+ [SMACK_ATTR_TRANSMUTE] = "security.SMACK64TRANSMUTE",
+ [SMACK_ATTR_IPIN] = "security.SMACK64IPIN",
+ [SMACK_ATTR_IPOUT] = "security.SMACK64IPOUT",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(smack_attr, SmackAttr);
+int mac_smack_read(const char *path, SmackAttr attr, char **label) {
assert(path);
+ assert(attr >= 0 && attr < _SMACK_ATTR_MAX);
+ assert(label);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
- if (label)
- r = lsetxattr(path, "security.SMACK64", label, strlen(label), 0);
- else
- r = lremovexattr(path, "security.SMACK64");
- if (r < 0)
- return -errno;
-#endif
-
- return r;
+ return getxattr_malloc(path, smack_attr_to_string(attr), label, true);
}
-int mac_smack_apply_fd(int fd, const char *label) {
- int r = 0;
-
+int mac_smack_read_fd(int fd, SmackAttr attr, char **label) {
assert(fd >= 0);
+ assert(attr >= 0 && attr < _SMACK_ATTR_MAX);
+ assert(label);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
- if (label)
- r = fsetxattr(fd, "security.SMACK64", label, strlen(label), 0);
- else
- r = fremovexattr(fd, "security.SMACK64");
- if (r < 0)
- return -errno;
-#endif
-
- return r;
+ return fgetxattr_malloc(fd, smack_attr_to_string(attr), label);
}
-int mac_smack_apply_ip_out_fd(int fd, const char *label) {
- int r = 0;
+int mac_smack_apply(const char *path, SmackAttr attr, const char *label) {
+ int r;
- assert(fd >= 0);
+ assert(path);
+ assert(attr >= 0 && attr < _SMACK_ATTR_MAX);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
if (label)
- r = fsetxattr(fd, "security.SMACK64IPOUT", label, strlen(label), 0);
+ r = lsetxattr(path, smack_attr_to_string(attr), label, strlen(label), 0);
else
- r = fremovexattr(fd, "security.SMACK64IPOUT");
+ r = lremovexattr(path, smack_attr_to_string(attr));
if (r < 0)
return -errno;
-#endif
- return r;
+ return 0;
}
-int mac_smack_apply_ip_in_fd(int fd, const char *label) {
- int r = 0;
+int mac_smack_apply_fd(int fd, SmackAttr attr, const char *label) {
+ int r;
assert(fd >= 0);
+ assert(attr >= 0 && attr < _SMACK_ATTR_MAX);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
if (label)
- r = fsetxattr(fd, "security.SMACK64IPIN", label, strlen(label), 0);
+ r = fsetxattr(fd, smack_attr_to_string(attr), label, strlen(label), 0);
else
- r = fremovexattr(fd, "security.SMACK64IPIN");
+ r = fremovexattr(fd, smack_attr_to_string(attr));
if (r < 0)
return -errno;
-#endif
- return r;
+ return 0;
}
int mac_smack_apply_pid(pid_t pid, const char *label) {
-
-#ifdef HAVE_SMACK
const char *p;
-#endif
int r = 0;
assert(label);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
r = write_string_file(p, label, 0);
if (r < 0)
return r;
-#endif
return r;
}
-int mac_smack_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
-
-#ifdef HAVE_SMACK
+int mac_smack_fix(const char *path, LabelFixFlags flags) {
+ char procfs_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)];
+ _cleanup_close_ int fd = -1;
+ const char *label;
struct stat st;
-#endif
- int r = 0;
+ int r;
assert(path);
-#ifdef HAVE_SMACK
if (!mac_smack_use())
return 0;
+ /* Path must be in /dev. Note that this check is pretty sloppy, as we might be called with non-normalized paths
+ * and hence not detect all cases of /dev. */
+
+ if (path_is_absolute(path)) {
+ if (!path_startswith(path, "/dev"))
+ return 0;
+ } else {
+ _cleanup_free_ char *cwd = NULL;
+
+ r = safe_getcwd(&cwd);
+ if (r < 0)
+ return r;
+
+ if (!path_startswith(cwd, "/dev"))
+ return 0;
+ }
+
+ fd = open(path, O_NOFOLLOW|O_CLOEXEC|O_PATH);
+ if (fd < 0) {
+ if ((flags & LABEL_IGNORE_ENOENT) && errno == ENOENT)
+ return 0;
+
+ return -errno;
+ }
+
+ if (fstat(fd, &st) < 0)
+ return -errno;
+
/*
- * Path must be in /dev and must exist
+ * Label directories and character devices "*".
+ * Label symlinks "_".
+ * Don't change anything else.
*/
- if (!path_startswith(path, "/dev"))
+
+ if (S_ISDIR(st.st_mode))
+ label = SMACK_STAR_LABEL;
+ else if (S_ISLNK(st.st_mode))
+ label = SMACK_FLOOR_LABEL;
+ else if (S_ISCHR(st.st_mode))
+ label = SMACK_STAR_LABEL;
+ else
return 0;
- r = lstat(path, &st);
- if (r >= 0) {
- const char *label;
-
- /*
- * Label directories and character devices "*".
- * Label symlinks "_".
- * Don't change anything else.
- */
-
- if (S_ISDIR(st.st_mode))
- label = SMACK_STAR_LABEL;
- else if (S_ISLNK(st.st_mode))
- label = SMACK_FLOOR_LABEL;
- else if (S_ISCHR(st.st_mode))
- label = SMACK_STAR_LABEL;
- else
- return 0;
+ xsprintf(procfs_path, "/proc/self/fd/%i", fd);
+ if (setxattr(procfs_path, "security.SMACK64", label, strlen(label), 0) < 0) {
+ _cleanup_free_ char *old_label = NULL;
- r = lsetxattr(path, "security.SMACK64", label, strlen(label), 0);
+ r = -errno;
/* If the FS doesn't support labels, then exit without warning */
- if (r < 0 && errno == EOPNOTSUPP)
+ if (r == -EOPNOTSUPP)
return 0;
- }
- if (r < 0) {
- /* Ignore ENOENT in some cases */
- if (ignore_enoent && errno == ENOENT)
+ /* It the FS is read-only and we were told to ignore failures caused by that, suppress error */
+ if (r == -EROFS && (flags & LABEL_IGNORE_EROFS))
return 0;
- if (ignore_erofs && errno == EROFS)
+ /* If the old label is identical to the new one, suppress any kind of error */
+ if (getxattr_malloc(procfs_path, "security.SMACK64", &old_label, false) >= 0 &&
+ streq(old_label, label))
return 0;
- r = log_debug_errno(errno, "Unable to fix SMACK label of %s: %m", path);
+ return log_debug_errno(r, "Unable to fix SMACK label of %s: %m", path);
}
-#endif
+
+ return 0;
+}
+
+int mac_smack_copy(const char *dest, const char *src) {
+ int r = 0;
+ _cleanup_free_ char *label = NULL;
+
+ assert(dest);
+ assert(src);
+
+ r = mac_smack_read(src, SMACK_ATTR_ACCESS, &label);
+ if (r < 0)
+ return r;
+
+ r = mac_smack_apply(dest, SMACK_ATTR_ACCESS, label);
+ if (r < 0)
+ return r;
return r;
}
+
+#else
+bool mac_smack_use(void) {
+ return false;
+}
+
+int mac_smack_read(const char *path, SmackAttr attr, char **label) {
+ return -EOPNOTSUPP;
+}
+
+int mac_smack_read_fd(int fd, SmackAttr attr, char **label) {
+ return -EOPNOTSUPP;
+}
+
+int mac_smack_apply(const char *path, SmackAttr attr, const char *label) {
+ return 0;
+}
+
+int mac_smack_apply_fd(int fd, SmackAttr attr, const char *label) {
+ return 0;
+}
+
+int mac_smack_apply_pid(pid_t pid, const char *label) {
+ return 0;
+}
+
+int mac_smack_fix(const char *path, LabelFixFlags flags) {
+ return 0;
+}
+
+int mac_smack_copy(const char *dest, const char *src) {
+ return 0;
+}
+#endif