X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fsmack-util.c;h=64e213489e21726047f71f6898e4f5fd8536fbbf;hp=8f83562bf6804701775fed4970b6073c9a510d97;hb=fae5694e1ab3226fea410aea86bd039831395ccf;hpb=d2edfae0f9bdbecf6a8518e2a5bcf06f470e0d9e

diff --git a/src/shared/smack-util.c b/src/shared/smack-util.c
index 8f83562bf..64e213489 100644
--- a/src/shared/smack-util.c
+++ b/src/shared/smack-util.c
@@ -21,69 +21,187 @@
   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 "fileio.h"
 #include "smack-util.h"
 
-bool use_smack(void) {
+#define SMACK_FLOOR_LABEL "_"
+#define SMACK_STAR_LABEL  "*"
+
+bool mac_smack_use(void) {
 #ifdef HAVE_SMACK
-        static int use_smack_cached = -1;
+        static int cached_use = -1;
 
-        if (use_smack_cached < 0)
-                use_smack_cached = access("/sys/fs/smackfs/", F_OK) >= 0;
+        if (cached_use < 0)
+                cached_use = access("/sys/fs/smackfs/", F_OK) >= 0;
 
-        return use_smack_cached;
+        return cached_use;
 #else
         return false;
 #endif
+}
+
+int mac_smack_apply(const char *path, const char *label) {
+        int r = 0;
+
+        assert(path);
+
+#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;
 }
 
-int smack_label_path(const char *path, const char *label) {
+int mac_smack_apply_fd(int fd, const char *label) {
+        int r = 0;
+
+        assert(fd >= 0);
+
 #ifdef HAVE_SMACK
-        if (!use_smack())
+        if (!mac_smack_use())
                 return 0;
 
         if (label)
-                return setxattr(path, "security.SMACK64", label, strlen(label), 0);
+                r = fsetxattr(fd, "security.SMACK64", label, strlen(label), 0);
         else
-                return lremovexattr(path, "security.SMACK64");
-#else
-        return 0;
+                r = fremovexattr(fd, "security.SMACK64");
+        if (r < 0)
+                return -errno;
 #endif
+
+        return r;
 }
 
-int smack_label_fd(int fd, const char *label) {
+int mac_smack_apply_ip_out_fd(int fd, const char *label) {
+        int r = 0;
+
+        assert(fd >= 0);
+
 #ifdef HAVE_SMACK
-        if (!use_smack())
+        if (!mac_smack_use())
                 return 0;
 
-        return fsetxattr(fd, "security.SMACK64", label, strlen(label), 0);
-#else
-        return 0;
+        if (label)
+                r = fsetxattr(fd, "security.SMACK64IPOUT", label, strlen(label), 0);
+        else
+                r = fremovexattr(fd, "security.SMACK64IPOUT");
+        if (r < 0)
+                return -errno;
 #endif
+
+        return r;
 }
 
-int smack_label_ip_out_fd(int fd, const char *label) {
+int mac_smack_apply_ip_in_fd(int fd, const char *label) {
+        int r = 0;
+
+        assert(fd >= 0);
+
 #ifdef HAVE_SMACK
-        if (!use_smack())
+        if (!mac_smack_use())
                 return 0;
 
-        return fsetxattr(fd, "security.SMACK64IPOUT", label, strlen(label), 0);
-#else
-        return 0;
+        if (label)
+                r = fsetxattr(fd, "security.SMACK64IPIN", label, strlen(label), 0);
+        else
+                r = fremovexattr(fd, "security.SMACK64IPIN");
+        if (r < 0)
+                return -errno;
 #endif
+
+        return r;
 }
 
-int smack_label_ip_in_fd(int fd, const char *label) {
+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 (!use_smack())
+        if (!mac_smack_use())
                 return 0;
 
-        return fsetxattr(fd, "security.SMACK64IPIN", label, strlen(label), 0);
-#else
-        return 0;
+        p = procfs_file_alloca(pid, "attr/current");
+        r = write_string_file(p, label);
+        if (r < 0)
+                return r;
+#endif
+
+        return r;
+}
+
+int mac_smack_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
+
+#ifdef HAVE_SMACK
+        struct stat st;
+#endif
+        int r = 0;
+
+        assert(path);
+
+#ifdef HAVE_SMACK
+        if (!mac_smack_use())
+                return 0;
+
+        /*
+         * Path must be in /dev and must exist
+         */
+        if (!path_startswith(path, "/dev"))
+                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;
+
+                r = lsetxattr(path, "security.SMACK64", label, strlen(label), 0);
+
+                /* 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;
+
+                r = log_debug_errno(errno, "Unable to fix SMACK label of %s: %m", path);
+        }
 #endif
+
+        return r;
 }