[systemd-devel] [PATCH 1/2] label: rearrange mandatory access control(MAC) apis

WaLyong Cho walyong.cho at gmail.com
Thu Oct 23 01:23:45 PDT 2014


From: WaLyong Cho <walyong.cho at samsung.com>

move label apis to selinux-util.ch or smack-util.ch appropriately.
---
 src/shared/label.c        | 554 ----------------------------------------------
 src/shared/label.h        |  31 +--
 src/shared/mkdir-label.c  |  26 +++
 src/shared/mkdir.h        |   2 +-
 src/shared/selinux-util.c | 481 +++++++++++++++++++++++++++++++++++++++-
 src/shared/selinux-util.h |  27 +++
 src/shared/smack-util.c   |  45 +++-
 src/shared/smack-util.h   |   1 +
 8 files changed, 575 insertions(+), 592 deletions(-)

diff --git a/src/shared/label.c b/src/shared/label.c
index 69d4616..b48a4ff 100644
--- a/src/shared/label.c
+++ b/src/shared/label.c
@@ -19,170 +19,8 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <errno.h>
-#include <unistd.h>
-#include <malloc.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <sys/xattr.h>
-#ifdef HAVE_SELINUX
-#include <selinux/selinux.h>
-#include <selinux/label.h>
-#include <selinux/context.h>
-#endif
-
 #include "label.h"
-#include "strv.h"
 #include "util.h"
-#include "path-util.h"
-#include "selinux-util.h"
-#include "smack-util.h"
-
-#ifdef HAVE_SELINUX
-DEFINE_TRIVIAL_CLEANUP_FUNC(security_context_t, freecon);
-DEFINE_TRIVIAL_CLEANUP_FUNC(context_t, context_free);
-
-#define _cleanup_security_context_free_ _cleanup_(freeconp)
-#define _cleanup_context_free_ _cleanup_(context_freep)
-
-static struct selabel_handle *label_hnd = NULL;
-#endif
-
-static int smack_relabel_in_dev(const char *path) {
-        int r = 0;
-
-#ifdef HAVE_SMACK
-        struct stat sb;
-        const char *label;
-
-        /*
-         * Path must be in /dev and must exist
-         */
-        if (!path_startswith(path, "/dev"))
-                return 0;
-
-        r = lstat(path, &sb);
-        if (r < 0)
-                return -errno;
-
-        /*
-         * Label directories and character devices "*".
-         * Label symlinks "_".
-         * Don't change anything else.
-         */
-        if (S_ISDIR(sb.st_mode))
-                label = SMACK_STAR_LABEL;
-        else if (S_ISLNK(sb.st_mode))
-                label = SMACK_FLOOR_LABEL;
-        else if (S_ISCHR(sb.st_mode))
-                label = SMACK_STAR_LABEL;
-        else
-                return 0;
-
-        r = setxattr(path, "security.SMACK64", label, strlen(label), 0);
-        if (r < 0) {
-                log_error("Smack relabeling \"%s\" %m", path);
-                return -errno;
-        }
-#endif
-
-        return r;
-}
-
-int label_init(const char *prefix) {
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        usec_t before_timestamp, after_timestamp;
-        struct mallinfo before_mallinfo, after_mallinfo;
-
-        if (!use_selinux())
-                return 0;
-
-        if (label_hnd)
-                return 0;
-
-        before_mallinfo = mallinfo();
-        before_timestamp = now(CLOCK_MONOTONIC);
-
-        if (prefix) {
-                struct selinux_opt options[] = {
-                        { .type = SELABEL_OPT_SUBSET, .value = prefix },
-                };
-
-                label_hnd = selabel_open(SELABEL_CTX_FILE, options, ELEMENTSOF(options));
-        } else
-                label_hnd = selabel_open(SELABEL_CTX_FILE, NULL, 0);
-
-        if (!label_hnd) {
-                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
-                         "Failed to initialize SELinux context: %m");
-                r = security_getenforce() == 1 ? -errno : 0;
-        } else  {
-                char timespan[FORMAT_TIMESPAN_MAX];
-                int l;
-
-                after_timestamp = now(CLOCK_MONOTONIC);
-                after_mallinfo = mallinfo();
-
-                l = after_mallinfo.uordblks > before_mallinfo.uordblks ? after_mallinfo.uordblks - before_mallinfo.uordblks : 0;
-
-                log_debug("Successfully loaded SELinux database in %s, size on heap is %iK.",
-                          format_timespan(timespan, sizeof(timespan), after_timestamp - before_timestamp, 0),
-                          (l+1023)/1024);
-        }
-#endif
-
-        return r;
-}
-
-static int label_fix_selinux(const char *path, bool ignore_enoent, bool ignore_erofs) {
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        struct stat st;
-        security_context_t fcon;
-
-        if (!label_hnd)
-                return 0;
-
-        r = lstat(path, &st);
-        if (r == 0) {
-                r = selabel_lookup_raw(label_hnd, &fcon, path, st.st_mode);
-
-                /* If there's no label to set, then exit without warning */
-                if (r < 0 && errno == ENOENT)
-                        return 0;
-
-                if (r == 0) {
-                        r = lsetfilecon(path, fcon);
-                        freecon(fcon);
-
-                        /* If the FS doesn't support labels, then exit without warning */
-                        if (r < 0 && errno == ENOTSUP)
-                                return 0;
-                }
-        }
-
-        if (r < 0) {
-                /* Ignore ENOENT in some cases */
-                if (ignore_enoent && errno == ENOENT)
-                        return 0;
-
-                if (ignore_erofs && errno == EROFS)
-                        return 0;
-
-                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
-                         "Unable to fix label of %s: %m", path);
-                r = security_getenforce() == 1 ? -errno : 0;
-        }
-#endif
-
-        return r;
-}
 
 int label_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
         int r = 0;
@@ -201,395 +39,3 @@ int label_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
 
         return r;
 }
-
-void label_finish(void) {
-
-#ifdef HAVE_SELINUX
-        if (!use_selinux())
-                return;
-
-        if (label_hnd)
-                selabel_close(label_hnd);
-#endif
-}
-
-int label_get_create_label_from_exe(const char *exe, char **label) {
-
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        security_context_t mycon = NULL, fcon = NULL;
-        security_class_t sclass;
-
-        if (!use_selinux()) {
-                *label = NULL;
-                return 0;
-        }
-
-        r = getcon(&mycon);
-        if (r < 0)
-                goto fail;
-
-        r = getfilecon(exe, &fcon);
-        if (r < 0)
-                goto fail;
-
-        sclass = string_to_security_class("process");
-        r = security_compute_create(mycon, fcon, sclass, (security_context_t *) label);
-        if (r == 0)
-                log_debug("SELinux Socket context for %s will be set to %s", exe, *label);
-
-fail:
-        if (r < 0 && security_getenforce() == 1)
-                r = -errno;
-
-        freecon(mycon);
-        freecon(fcon);
-#endif
-
-        return r;
-}
-
-int label_get_our_label(char **label) {
-        int r = -EOPNOTSUPP;
-
-#ifdef HAVE_SELINUX
-        char *l = NULL;
-
-        r = getcon(&l);
-        if (r < 0)
-                return r;
-
-        *label = l;
-#endif
-
-        return r;
-}
-
-int label_get_child_mls_label(int socket_fd, const char *exe, char **label) {
-        int r = -EOPNOTSUPP;
-
-#ifdef HAVE_SELINUX
-
-        _cleanup_security_context_free_ security_context_t mycon = NULL, peercon = NULL, fcon = NULL, ret = NULL;
-        _cleanup_context_free_ context_t pcon = NULL, bcon = NULL;
-        security_class_t sclass;
-
-        const char *range = NULL;
-
-        assert(socket_fd >= 0);
-        assert(exe);
-        assert(label);
-
-        r = getcon(&mycon);
-        if (r < 0) {
-                r = -EINVAL;
-                goto out;
-        }
-
-        r = getpeercon(socket_fd, &peercon);
-        if (r < 0) {
-                r = -EINVAL;
-                goto out;
-        }
-
-        r = getexeccon(&fcon);
-        if (r < 0) {
-                r = -EINVAL;
-                goto out;
-        }
-
-        if (!fcon) {
-                /* If there is no context set for next exec let's use context
-                   of target executable */
-                r = getfilecon(exe, &fcon);
-                if (r < 0) {
-                        r = -errno;
-                        goto out;
-                }
-        }
-
-        bcon = context_new(mycon);
-        if (!bcon) {
-                r = -ENOMEM;
-                goto out;
-        }
-
-        pcon = context_new(peercon);
-        if (!pcon) {
-                r = -ENOMEM;
-                goto out;
-        }
-
-        range = context_range_get(pcon);
-        if (!range) {
-                r = -errno;
-                goto out;
-        }
-
-        r = context_range_set(bcon, range);
-        if (r) {
-                r = -errno;
-                goto out;
-        }
-
-        freecon(mycon);
-        mycon = strdup(context_str(bcon));
-        if (!mycon) {
-                r = -errno;
-                goto out;
-        }
-
-        sclass = string_to_security_class("process");
-        r = security_compute_create(mycon, fcon, sclass, &ret);
-        if (r < 0) {
-                r = -EINVAL;
-                goto out;
-        }
-
-        *label = ret;
-        ret = NULL;
-        r = 0;
-
-out:
-        if (r < 0 && security_getenforce() == 1)
-                return r;
-#endif
-        return r;
-}
-
-int label_context_set(const char *path, mode_t mode) {
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        security_context_t filecon = NULL;
-
-        if (!use_selinux() || !label_hnd)
-                return 0;
-
-        r = selabel_lookup_raw(label_hnd, &filecon, path, mode);
-        if (r < 0 && errno != ENOENT)
-                r = -errno;
-        else if (r == 0) {
-                r = setfscreatecon(filecon);
-                if (r < 0) {
-                        log_error("Failed to set SELinux file context on %s: %m", path);
-                        r = -errno;
-                }
-
-                freecon(filecon);
-        }
-
-        if (r < 0 && security_getenforce() == 0)
-                r = 0;
-#endif
-
-        return r;
-}
-
-int label_socket_set(const char *label) {
-
-#ifdef HAVE_SELINUX
-        if (!use_selinux())
-                return 0;
-
-        if (setsockcreatecon((security_context_t) label) < 0) {
-                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
-                         "Failed to set SELinux context (%s) on socket: %m", label);
-
-                if (security_getenforce() == 1)
-                        return -errno;
-        }
-#endif
-
-        return 0;
-}
-
-void label_context_clear(void) {
-
-#ifdef HAVE_SELINUX
-        PROTECT_ERRNO;
-
-        if (!use_selinux())
-                return;
-
-        setfscreatecon(NULL);
-#endif
-}
-
-void label_socket_clear(void) {
-
-#ifdef HAVE_SELINUX
-        PROTECT_ERRNO;
-
-        if (!use_selinux())
-                return;
-
-        setsockcreatecon(NULL);
-#endif
-}
-
-void label_free(const char *label) {
-
-#ifdef HAVE_SELINUX
-        if (!use_selinux())
-                return;
-
-        freecon((security_context_t) label);
-#endif
-}
-
-static int label_mkdir_selinux(const char *path, mode_t mode) {
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        /* Creates a directory and labels it according to the SELinux policy */
-        security_context_t fcon = NULL;
-
-        if (!label_hnd)
-                return 0;
-
-        if (path_is_absolute(path))
-                r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFDIR);
-        else {
-                _cleanup_free_ char *newpath;
-
-                newpath = path_make_absolute_cwd(path);
-                if (!newpath)
-                        return -ENOMEM;
-
-                r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFDIR);
-        }
-
-        if (r == 0)
-                r = setfscreatecon(fcon);
-
-        if (r < 0 && errno != ENOENT) {
-                log_error("Failed to set security context %s for %s: %m", fcon, path);
-
-                if (security_getenforce() == 1) {
-                        r = -errno;
-                        goto finish;
-                }
-        }
-
-        r = mkdir(path, mode);
-        if (r < 0)
-                r = -errno;
-
-finish:
-        setfscreatecon(NULL);
-        freecon(fcon);
-#endif
-
-        return r;
-}
-
-int label_mkdir(const char *path, mode_t mode) {
-        int r;
-
-        if (use_selinux()) {
-                r = label_mkdir_selinux(path, mode);
-                if (r < 0)
-                        return r;
-        }
-
-        if (use_smack()) {
-                r = mkdir(path, mode);
-                if (r < 0 && errno != EEXIST)
-                        return -errno;
-
-                r = smack_relabel_in_dev(path);
-                if (r < 0)
-                        return r;
-        }
-
-        r = mkdir(path, mode);
-        if (r < 0 && errno != EEXIST)
-                return -errno;
-
-        return 0;
-}
-
-int label_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
-
-        /* Binds a socket and label its file system object according to the SELinux policy */
-
-#ifdef HAVE_SELINUX
-        security_context_t fcon = NULL;
-        const struct sockaddr_un *un;
-        char *path;
-        int r;
-
-        assert(fd >= 0);
-        assert(addr);
-        assert(addrlen >= sizeof(sa_family_t));
-
-        if (!use_selinux() || !label_hnd)
-                goto skipped;
-
-        /* Filter out non-local sockets */
-        if (addr->sa_family != AF_UNIX)
-                goto skipped;
-
-        /* Filter out anonymous sockets */
-        if (addrlen < sizeof(sa_family_t) + 1)
-                goto skipped;
-
-        /* Filter out abstract namespace sockets */
-        un = (const struct sockaddr_un*) addr;
-        if (un->sun_path[0] == 0)
-                goto skipped;
-
-        path = strndupa(un->sun_path, addrlen - offsetof(struct sockaddr_un, sun_path));
-
-        if (path_is_absolute(path))
-                r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK);
-        else {
-                _cleanup_free_ char *newpath;
-
-                newpath = path_make_absolute_cwd(path);
-                if (!newpath)
-                        return -ENOMEM;
-
-                r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK);
-        }
-
-        if (r == 0)
-                r = setfscreatecon(fcon);
-
-        if (r < 0 && errno != ENOENT) {
-                log_error("Failed to set security context %s for %s: %m", fcon, path);
-
-                if (security_getenforce() == 1) {
-                        r = -errno;
-                        goto finish;
-                }
-        }
-
-        r = bind(fd, addr, addrlen);
-        if (r < 0)
-                r = -errno;
-
-finish:
-        setfscreatecon(NULL);
-        freecon(fcon);
-
-        return r;
-
-skipped:
-#endif
-        return bind(fd, addr, addrlen) < 0 ? -errno : 0;
-}
-
-int label_apply(const char *path, const char *label) {
-        int r = 0;
-
-#ifdef HAVE_SELINUX
-        if (!use_selinux())
-                return 0;
-
-        r = setfilecon(path, (char *)label);
-#endif
-        return r;
-}
diff --git a/src/shared/label.h b/src/shared/label.h
index ce1e5c3..1859f84 100644
--- a/src/shared/label.h
+++ b/src/shared/label.h
@@ -21,34 +21,7 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <sys/types.h>
-#include <stdbool.h>
-#include <sys/socket.h>
-#include <stdio.h>
-
-int label_init(const char *prefix);
-void label_finish(void);
+#include "selinux-util.h"
+#include "smack-util.h"
 
 int label_fix(const char *path, bool ignore_enoent, bool ignore_erofs);
-
-int label_socket_set(const char *label);
-void label_socket_clear(void);
-
-int label_context_set(const char *path, mode_t mode);
-void label_context_clear(void);
-
-void label_free(const char *label);
-
-int label_get_create_label_from_exe(const char *exe, char **label);
-int label_get_our_label(char **label);
-int label_get_child_mls_label(int socket_fd, const char *exec, char **label);
-
-int label_mkdir(const char *path, mode_t mode);
-
-int label_bind(int fd, const struct sockaddr *addr, socklen_t addrlen);
-
-int label_apply(const char *path, const char *label);
-
-int label_write_one_line_file_atomic(const char *fn, const char *line);
-int label_write_env_file(const char *fname, char **l);
-int label_fopen_temporary(const char *path, FILE **_f, char **_temp_path);
diff --git a/src/shared/mkdir-label.c b/src/shared/mkdir-label.c
index 43ea2c2..c41045e 100644
--- a/src/shared/mkdir-label.c
+++ b/src/shared/mkdir-label.c
@@ -32,6 +32,32 @@
 #include "path-util.h"
 #include "mkdir.h"
 
+static int label_mkdir(const char *path, mode_t mode) {
+        int r;
+
+        if (use_selinux()) {
+                r = label_mkdir_selinux(path, mode);
+                if (r < 0)
+                        return r;
+        }
+
+        if (use_smack()) {
+                r = mkdir(path, mode);
+                if (r < 0 && errno != EEXIST)
+                        return -errno;
+
+                r = smack_relabel_in_dev(path);
+                if (r < 0)
+                        return r;
+        }
+
+        r = mkdir(path, mode);
+        if (r < 0 && errno != EEXIST)
+                return -errno;
+
+        return 0;
+}
+
 int mkdir_label(const char *path, mode_t mode) {
         return label_mkdir(path, mode);
 }
diff --git a/src/shared/mkdir.h b/src/shared/mkdir.h
index ca38d21..1586214 100644
--- a/src/shared/mkdir.h
+++ b/src/shared/mkdir.h
@@ -29,7 +29,7 @@ int mkdir_safe(const char *path, mode_t mode, uid_t uid, gid_t gid);
 int mkdir_parents(const char *path, mode_t mode);
 int mkdir_p(const char *path, mode_t mode);
 
-/* selinux versions */
+/* mandatory access control(MAC) versions */
 int mkdir_label(const char *path, mode_t mode);
 int mkdir_safe_label(const char *path, mode_t mode, uid_t uid, gid_t gid);
 int mkdir_parents_label(const char *path, mode_t mode);
diff --git a/src/shared/selinux-util.c b/src/shared/selinux-util.c
index 026ae5a..05ed61c 100644
--- a/src/shared/selinux-util.c
+++ b/src/shared/selinux-util.c
@@ -19,33 +19,502 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include <errno.h>
+#include <unistd.h>
+#include <malloc.h>
+#include <sys/un.h>
+#ifdef HAVE_SELINUX
+#include <selinux/selinux.h>
+#include <selinux/label.h>
+#include <selinux/context.h>
+#endif
+
+#include "strv.h"
+#include "path-util.h"
 #include "selinux-util.h"
 
 #ifdef HAVE_SELINUX
+DEFINE_TRIVIAL_CLEANUP_FUNC(security_context_t, freecon);
+DEFINE_TRIVIAL_CLEANUP_FUNC(context_t, context_free);
 
-#include <selinux/selinux.h>
+#define _cleanup_security_context_free_ _cleanup_(freeconp)
+#define _cleanup_context_free_ _cleanup_(context_freep)
 
 static int use_selinux_cached = -1;
+static struct selabel_handle *label_hnd = NULL;
+#endif
 
 bool use_selinux(void) {
-
+#ifdef HAVE_SELINUX
         if (use_selinux_cached < 0)
                 use_selinux_cached = is_selinux_enabled() > 0;
 
         return use_selinux_cached;
+#else
+        return false;
+#endif
 }
 
 void retest_selinux(void) {
+#ifdef HAVE_SELINUX
         use_selinux_cached = -1;
+#endif
 }
 
-#else
+int label_init(const char *prefix) {
+        int r = 0;
 
-bool use_selinux(void) {
-        return false;
+#ifdef HAVE_SELINUX
+        usec_t before_timestamp, after_timestamp;
+        struct mallinfo before_mallinfo, after_mallinfo;
+
+        if (!use_selinux())
+                return 0;
+
+        if (label_hnd)
+                return 0;
+
+        before_mallinfo = mallinfo();
+        before_timestamp = now(CLOCK_MONOTONIC);
+
+        if (prefix) {
+                struct selinux_opt options[] = {
+                        { .type = SELABEL_OPT_SUBSET, .value = prefix },
+                };
+
+                label_hnd = selabel_open(SELABEL_CTX_FILE, options, ELEMENTSOF(options));
+        } else
+                label_hnd = selabel_open(SELABEL_CTX_FILE, NULL, 0);
+
+        if (!label_hnd) {
+                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
+                         "Failed to initialize SELinux context: %m");
+                r = security_getenforce() == 1 ? -errno : 0;
+        } else  {
+                char timespan[FORMAT_TIMESPAN_MAX];
+                int l;
+
+                after_timestamp = now(CLOCK_MONOTONIC);
+                after_mallinfo = mallinfo();
+
+                l = after_mallinfo.uordblks > before_mallinfo.uordblks ? after_mallinfo.uordblks - before_mallinfo.uordblks : 0;
+
+                log_debug("Successfully loaded SELinux database in %s, size on heap is %iK.",
+                          format_timespan(timespan, sizeof(timespan), after_timestamp - before_timestamp, 0),
+                          (l+1023)/1024);
+        }
+#endif
+
+        return r;
 }
 
-void retest_selinux(void) {
+int label_fix_selinux(const char *path, bool ignore_enoent, bool ignore_erofs) {
+        int r = 0;
+
+#ifdef HAVE_SELINUX
+        struct stat st;
+        security_context_t fcon;
+
+        if (!label_hnd)
+                return 0;
+
+        r = lstat(path, &st);
+        if (r == 0) {
+                r = selabel_lookup_raw(label_hnd, &fcon, path, st.st_mode);
+
+                /* If there's no label to set, then exit without warning */
+                if (r < 0 && errno == ENOENT)
+                        return 0;
+
+                if (r == 0) {
+                        r = lsetfilecon(path, fcon);
+                        freecon(fcon);
+
+                        /* If the FS doesn't support labels, then exit without warning */
+                        if (r < 0 && errno == ENOTSUP)
+                                return 0;
+                }
+        }
+
+        if (r < 0) {
+                /* Ignore ENOENT in some cases */
+                if (ignore_enoent && errno == ENOENT)
+                        return 0;
+
+                if (ignore_erofs && errno == EROFS)
+                        return 0;
+
+                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
+                         "Unable to fix label of %s: %m", path);
+                r = security_getenforce() == 1 ? -errno : 0;
+        }
+#endif
+
+        return r;
+}
+
+void label_finish(void) {
+
+#ifdef HAVE_SELINUX
+        if (!use_selinux())
+                return;
+
+        if (label_hnd)
+                selabel_close(label_hnd);
+#endif
 }
 
+int label_get_create_label_from_exe(const char *exe, char **label) {
+
+        int r = 0;
+
+#ifdef HAVE_SELINUX
+        security_context_t mycon = NULL, fcon = NULL;
+        security_class_t sclass;
+
+        if (!use_selinux()) {
+                *label = NULL;
+                return 0;
+        }
+
+        r = getcon(&mycon);
+        if (r < 0)
+                goto fail;
+
+        r = getfilecon(exe, &fcon);
+        if (r < 0)
+                goto fail;
+
+        sclass = string_to_security_class("process");
+        r = security_compute_create(mycon, fcon, sclass, (security_context_t *) label);
+        if (r == 0)
+                log_debug("SELinux Socket context for %s will be set to %s", exe, *label);
+
+fail:
+        if (r < 0 && security_getenforce() == 1)
+                r = -errno;
+
+        freecon(mycon);
+        freecon(fcon);
+#endif
+
+        return r;
+}
+
+int label_get_our_label(char **label) {
+        int r = -EOPNOTSUPP;
+
+#ifdef HAVE_SELINUX
+        char *l = NULL;
+
+        r = getcon(&l);
+        if (r < 0)
+                return r;
+
+        *label = l;
 #endif
+
+        return r;
+}
+
+int label_get_child_mls_label(int socket_fd, const char *exe, char **label) {
+        int r = -EOPNOTSUPP;
+
+#ifdef HAVE_SELINUX
+
+        _cleanup_security_context_free_ security_context_t mycon = NULL, peercon = NULL, fcon = NULL, ret = NULL;
+        _cleanup_context_free_ context_t pcon = NULL, bcon = NULL;
+        security_class_t sclass;
+
+        const char *range = NULL;
+
+        assert(socket_fd >= 0);
+        assert(exe);
+        assert(label);
+
+        r = getcon(&mycon);
+        if (r < 0) {
+                r = -EINVAL;
+                goto out;
+        }
+
+        r = getpeercon(socket_fd, &peercon);
+        if (r < 0) {
+                r = -EINVAL;
+                goto out;
+        }
+
+        r = getexeccon(&fcon);
+        if (r < 0) {
+                r = -EINVAL;
+                goto out;
+        }
+
+        if (!fcon) {
+                /* If there is no context set for next exec let's use context
+                   of target executable */
+                r = getfilecon(exe, &fcon);
+                if (r < 0) {
+                        r = -errno;
+                        goto out;
+                }
+        }
+
+        bcon = context_new(mycon);
+        if (!bcon) {
+                r = -ENOMEM;
+                goto out;
+        }
+
+        pcon = context_new(peercon);
+        if (!pcon) {
+                r = -ENOMEM;
+                goto out;
+        }
+
+        range = context_range_get(pcon);
+        if (!range) {
+                r = -errno;
+                goto out;
+        }
+
+        r = context_range_set(bcon, range);
+        if (r) {
+                r = -errno;
+                goto out;
+        }
+
+        freecon(mycon);
+        mycon = strdup(context_str(bcon));
+        if (!mycon) {
+                r = -errno;
+                goto out;
+        }
+
+        sclass = string_to_security_class("process");
+        r = security_compute_create(mycon, fcon, sclass, &ret);
+        if (r < 0) {
+                r = -EINVAL;
+                goto out;
+        }
+
+        *label = ret;
+        ret = NULL;
+        r = 0;
+
+out:
+        if (r < 0 && security_getenforce() == 1)
+                return r;
+#endif
+        return r;
+}
+
+int label_context_set(const char *path, mode_t mode) {
+        int r = 0;
+
+#ifdef HAVE_SELINUX
+        security_context_t filecon = NULL;
+
+        if (!use_selinux() || !label_hnd)
+                return 0;
+
+        r = selabel_lookup_raw(label_hnd, &filecon, path, mode);
+        if (r < 0 && errno != ENOENT)
+                r = -errno;
+        else if (r == 0) {
+                r = setfscreatecon(filecon);
+                if (r < 0) {
+                        log_error("Failed to set SELinux file context on %s: %m", path);
+                        r = -errno;
+                }
+
+                freecon(filecon);
+        }
+
+        if (r < 0 && security_getenforce() == 0)
+                r = 0;
+#endif
+
+        return r;
+}
+
+int label_socket_set(const char *label) {
+
+#ifdef HAVE_SELINUX
+        if (!use_selinux())
+                return 0;
+
+        if (setsockcreatecon((security_context_t) label) < 0) {
+                log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
+                         "Failed to set SELinux context (%s) on socket: %m", label);
+
+                if (security_getenforce() == 1)
+                        return -errno;
+        }
+#endif
+
+        return 0;
+}
+
+void label_context_clear(void) {
+
+#ifdef HAVE_SELINUX
+        PROTECT_ERRNO;
+
+        if (!use_selinux())
+                return;
+
+        setfscreatecon(NULL);
+#endif
+}
+
+void label_socket_clear(void) {
+
+#ifdef HAVE_SELINUX
+        PROTECT_ERRNO;
+
+        if (!use_selinux())
+                return;
+
+        setsockcreatecon(NULL);
+#endif
+}
+
+void label_free(const char *label) {
+
+#ifdef HAVE_SELINUX
+        if (!use_selinux())
+                return;
+
+        freecon((security_context_t) label);
+#endif
+}
+
+int label_mkdir_selinux(const char *path, mode_t mode) {
+        int r = 0;
+
+#ifdef HAVE_SELINUX
+        /* Creates a directory and labels it according to the SELinux policy */
+        security_context_t fcon = NULL;
+
+        if (!label_hnd)
+                return 0;
+
+        if (path_is_absolute(path))
+                r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFDIR);
+        else {
+                _cleanup_free_ char *newpath;
+
+                newpath = path_make_absolute_cwd(path);
+                if (!newpath)
+                        return -ENOMEM;
+
+                r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFDIR);
+        }
+
+        if (r == 0)
+                r = setfscreatecon(fcon);
+
+        if (r < 0 && errno != ENOENT) {
+                log_error("Failed to set security context %s for %s: %m", fcon, path);
+
+                if (security_getenforce() == 1) {
+                        r = -errno;
+                        goto finish;
+                }
+        }
+
+        r = mkdir(path, mode);
+        if (r < 0)
+                r = -errno;
+
+finish:
+        setfscreatecon(NULL);
+        freecon(fcon);
+#endif
+
+        return r;
+}
+
+int label_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
+
+        /* Binds a socket and label its file system object according to the SELinux policy */
+
+#ifdef HAVE_SELINUX
+        security_context_t fcon = NULL;
+        const struct sockaddr_un *un;
+        char *path;
+        int r;
+
+        assert(fd >= 0);
+        assert(addr);
+        assert(addrlen >= sizeof(sa_family_t));
+
+        if (!use_selinux() || !label_hnd)
+                goto skipped;
+
+        /* Filter out non-local sockets */
+        if (addr->sa_family != AF_UNIX)
+                goto skipped;
+
+        /* Filter out anonymous sockets */
+        if (addrlen < sizeof(sa_family_t) + 1)
+                goto skipped;
+
+        /* Filter out abstract namespace sockets */
+        un = (const struct sockaddr_un*) addr;
+        if (un->sun_path[0] == 0)
+                goto skipped;
+
+        path = strndupa(un->sun_path, addrlen - offsetof(struct sockaddr_un, sun_path));
+
+        if (path_is_absolute(path))
+                r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK);
+        else {
+                _cleanup_free_ char *newpath;
+
+                newpath = path_make_absolute_cwd(path);
+                if (!newpath)
+                        return -ENOMEM;
+
+                r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK);
+        }
+
+        if (r == 0)
+                r = setfscreatecon(fcon);
+
+        if (r < 0 && errno != ENOENT) {
+                log_error("Failed to set security context %s for %s: %m", fcon, path);
+
+                if (security_getenforce() == 1) {
+                        r = -errno;
+                        goto finish;
+                }
+        }
+
+        r = bind(fd, addr, addrlen);
+        if (r < 0)
+                r = -errno;
+
+finish:
+        setfscreatecon(NULL);
+        freecon(fcon);
+
+        return r;
+
+skipped:
+#endif
+        return bind(fd, addr, addrlen) < 0 ? -errno : 0;
+}
+
+int label_apply(const char *path, const char *label) {
+        int r = 0;
+
+#ifdef HAVE_SELINUX
+        if (!use_selinux())
+                return 0;
+
+        r = setfilecon(path, (char *)label);
+#endif
+        return r;
+}
diff --git a/src/shared/selinux-util.h b/src/shared/selinux-util.h
index 4b81202..bdde8f5 100644
--- a/src/shared/selinux-util.h
+++ b/src/shared/selinux-util.h
@@ -21,7 +21,34 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include <sys/socket.h>
+#include <stdio.h>
 #include <stdbool.h>
 
 bool use_selinux(void);
 void retest_selinux(void);
+
+int label_init(const char *prefix);
+int label_fix_selinux(const char *path, bool ignore_enoent, bool ignore_erofs);
+void label_finish(void);
+
+int label_socket_set(const char *label);
+void label_socket_clear(void);
+
+int label_context_set(const char *path, mode_t mode);
+void label_context_clear(void);
+
+void label_free(const char *label);
+int label_mkdir_selinux(const char *path, mode_t mode);
+
+int label_get_create_label_from_exe(const char *exe, char **label);
+int label_get_our_label(char **label);
+int label_get_child_mls_label(int socket_fd, const char *exec, char **label);
+
+int label_bind(int fd, const struct sockaddr *addr, socklen_t addrlen);
+
+int label_apply(const char *path, const char *label);
+
+int label_write_one_line_file_atomic(const char *fn, const char *line);
+int label_write_env_file(const char *fname, char **l);
+int label_fopen_temporary(const char *path, FILE **_f, char **_temp_path);
diff --git a/src/shared/smack-util.c b/src/shared/smack-util.c
index 8f83562..04ee217 100644
--- a/src/shared/smack-util.c
+++ b/src/shared/smack-util.c
@@ -21,10 +21,10 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <unistd.h>
-#include <string.h>
 #include <sys/xattr.h>
 
+#include "util.h"
+#include "path-util.h"
 #include "smack-util.h"
 
 bool use_smack(void) {
@@ -87,3 +87,44 @@ int smack_label_ip_in_fd(int fd, const char *label) {
         return 0;
 #endif
 }
+
+int smack_relabel_in_dev(const char *path) {
+        int r = 0;
+
+#ifdef HAVE_SMACK
+        struct stat sb;
+        const char *label;
+
+        /*
+         * Path must be in /dev and must exist
+         */
+        if (!path_startswith(path, "/dev"))
+                return 0;
+
+        r = lstat(path, &sb);
+        if (r < 0)
+                return -errno;
+
+        /*
+         * Label directories and character devices "*".
+         * Label symlinks "_".
+         * Don't change anything else.
+         */
+        if (S_ISDIR(sb.st_mode))
+                label = SMACK_STAR_LABEL;
+        else if (S_ISLNK(sb.st_mode))
+                label = SMACK_FLOOR_LABEL;
+        else if (S_ISCHR(sb.st_mode))
+                label = SMACK_STAR_LABEL;
+        else
+                return 0;
+
+        r = setxattr(path, "security.SMACK64", label, strlen(label), 0);
+        if (r < 0) {
+                log_error("Smack relabeling \"%s\" %m", path);
+                return -errno;
+        }
+#endif
+
+        return r;
+}
diff --git a/src/shared/smack-util.h b/src/shared/smack-util.h
index 7370ae3..87d6434 100644
--- a/src/shared/smack-util.h
+++ b/src/shared/smack-util.h
@@ -34,3 +34,4 @@ int smack_label_path(const char *path, const char *label);
 int smack_label_fd(int fd, const char *label);
 int smack_label_ip_in_fd(int fd, const char *label);
 int smack_label_ip_out_fd(int fd, const char *label);
+int smack_relabel_in_dev(const char *path);
-- 
2.1.2



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