X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Flabel.c;h=82f10b21bd7142ed2adddd83a186afc67b28be0c;hp=69d4616183b3bf4dcdb04e5bfde8a137384bd35f;hb=4968105790c65af58d4ab42bffa2a4bedc0be8ee;hpb=5e78424f4a27c07be50e246308035c877f204038

diff --git a/src/shared/label.c b/src/shared/label.c
index 69d461618..82f10b21b 100644
--- a/src/shared/label.c
+++ b/src/shared/label.c
@@ -19,577 +19,62 @@
   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;
-}
+#include "util.h"
+#include "label.h"
 
 int label_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
-        int r = 0;
-
-        if (use_selinux()) {
-                r = label_fix_selinux(path, ignore_enoent, ignore_erofs);
-                if (r < 0)
-                        return r;
-        }
-
-        if (use_smack()) {
-                r = smack_relabel_in_dev(path);
-                if (r < 0)
-                        return r;
-        }
-
-        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;
-        }
+        int r, q;
 
-        r = getcon(&mycon);
-        if (r < 0)
-                goto fail;
+        r = mac_selinux_fix(path, ignore_enoent, ignore_erofs);
+        q = mac_smack_fix(path, ignore_enoent, ignore_erofs);
 
-        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;
+        if (q < 0)
+                return q;
 
-        *label = l;
-#endif
-
-        return r;
+        return 0;
 }
 
-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;
-        }
+int mkdir_label(const char *path, mode_t mode) {
+        int r;
 
-        *label = ret;
-        ret = NULL;
-        r = 0;
+        assert(path);
 
-out:
-        if (r < 0 && security_getenforce() == 1)
+        r = mac_selinux_create_file_prepare(path, S_IFDIR);
+        if (r < 0)
                 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)
+        if (mkdir(path, mode) < 0)
                 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;
+        mac_selinux_create_file_clear();
 
-        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 r;
 
-        return 0;
+        return mac_smack_fix(path, false, false);
 }
 
-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 symlink_label(const char *old_path, const char *new_path) {
         int r;
 
-        assert(fd >= 0);
-        assert(addr);
-        assert(addrlen >= sizeof(sa_family_t));
+        assert(old_path);
+        assert(new_path);
 
-        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);
+        r = mac_selinux_create_file_prepare(new_path, S_IFLNK);
         if (r < 0)
-                r = -errno;
-
-finish:
-        setfscreatecon(NULL);
-        freecon(fcon);
-
-        return r;
+                return r;
 
-skipped:
-#endif
-        return bind(fd, addr, addrlen) < 0 ? -errno : 0;
-}
+        if (symlink(old_path, new_path) < 0)
+                r = -errno;
 
-int label_apply(const char *path, const char *label) {
-        int r = 0;
+        mac_selinux_create_file_clear();
 
-#ifdef HAVE_SELINUX
-        if (!use_selinux())
-                return 0;
+        if (r < 0)
+                return r;
 
-        r = setfilecon(path, (char *)label);
-#endif
-        return r;
+        return mac_smack_fix(new_path, false, false);
 }