+static int
+do_bulk_access_check(struct hfsmount *hfsmp, struct vnode *vp,
+ struct vnop_ioctl_args *ap, int arg_size, vfs_context_t context)
+{
+ boolean_t is64bit;
+
+ /*
+ * NOTE: on entry, the vnode is locked. Incase this vnode
+ * happens to be in our list of file_ids, we'll note it
+ * avoid calling hfs_chashget_nowait() on that id as that
+ * will cause a "locking against myself" panic.
+ */
+ Boolean check_leaf = true;
+
+ struct user64_ext_access_t *user_access_structp;
+ struct user64_ext_access_t tmp_user_access;
+ struct access_cache cache;
+
+ int error = 0, prev_parent_check_ok=1;
+ unsigned int i;
+
+ short flags;
+ unsigned int num_files = 0;
+ int map_size = 0;
+ int num_parents = 0;
+ int *file_ids=NULL;
+ short *access=NULL;
+ char *bitmap=NULL;
+ cnid_t *parents=NULL;
+ int leaf_index;
+
+ cnid_t cnid;
+ cnid_t prevParent_cnid = 0;
+ unsigned int myPerms;
+ short myaccess = 0;
+ struct cat_attr cnattr;
+ CatalogKey catkey;
+ struct cnode *skip_cp = VTOC(vp);
+ kauth_cred_t cred = vfs_context_ucred(context);
+ proc_t p = vfs_context_proc(context);
+
+ is64bit = proc_is64bit(p);
+
+ /* initialize the local cache and buffers */
+ cache.numcached = 0;
+ cache.cachehits = 0;
+ cache.lookups = 0;
+ cache.acache = NULL;
+ cache.haveaccess = NULL;
+
+ /* struct copyin done during dispatch... need to copy file_id array separately */
+ if (ap->a_data == NULL) {
+ error = EINVAL;
+ goto err_exit_bulk_access;
+ }
+
+ if (is64bit) {
+ if (arg_size != sizeof(struct user64_ext_access_t)) {
+ error = EINVAL;
+ goto err_exit_bulk_access;
+ }
+
+ user_access_structp = (struct user64_ext_access_t *)ap->a_data;
+
+ } else if (arg_size == sizeof(struct user32_access_t)) {
+ struct user32_access_t *accessp = (struct user32_access_t *)ap->a_data;
+
+ // convert an old style bulk-access struct to the new style
+ tmp_user_access.flags = accessp->flags;
+ tmp_user_access.num_files = accessp->num_files;
+ tmp_user_access.map_size = 0;
+ tmp_user_access.file_ids = CAST_USER_ADDR_T(accessp->file_ids);
+ tmp_user_access.bitmap = USER_ADDR_NULL;
+ tmp_user_access.access = CAST_USER_ADDR_T(accessp->access);
+ tmp_user_access.num_parents = 0;
+ user_access_structp = &tmp_user_access;
+
+ } else if (arg_size == sizeof(struct user32_ext_access_t)) {
+ struct user32_ext_access_t *accessp = (struct user32_ext_access_t *)ap->a_data;
+
+ // up-cast from a 32-bit version of the struct
+ tmp_user_access.flags = accessp->flags;
+ tmp_user_access.num_files = accessp->num_files;
+ tmp_user_access.map_size = accessp->map_size;
+ tmp_user_access.num_parents = accessp->num_parents;
+
+ tmp_user_access.file_ids = CAST_USER_ADDR_T(accessp->file_ids);
+ tmp_user_access.bitmap = CAST_USER_ADDR_T(accessp->bitmap);
+ tmp_user_access.access = CAST_USER_ADDR_T(accessp->access);
+ tmp_user_access.parents = CAST_USER_ADDR_T(accessp->parents);
+
+ user_access_structp = &tmp_user_access;
+ } else {
+ error = EINVAL;
+ goto err_exit_bulk_access;
+ }
+
+ map_size = user_access_structp->map_size;
+
+ num_files = user_access_structp->num_files;
+
+ num_parents= user_access_structp->num_parents;
+
+ if (num_files < 1) {
+ goto err_exit_bulk_access;
+ }
+ if (num_files > 1024) {
+ error = EINVAL;
+ goto err_exit_bulk_access;
+ }
+
+ if (num_parents > 1024) {
+ error = EINVAL;
+ goto err_exit_bulk_access;
+ }
+
+ file_ids = (int *) kalloc(sizeof(int) * num_files);
+ access = (short *) kalloc(sizeof(short) * num_files);
+ if (map_size) {
+ bitmap = (char *) kalloc(sizeof(char) * map_size);
+ }
+
+ if (num_parents) {
+ parents = (cnid_t *) kalloc(sizeof(cnid_t) * num_parents);
+ }
+
+ cache.acache = (unsigned int *) kalloc(sizeof(int) * NUM_CACHE_ENTRIES);
+ cache.haveaccess = (unsigned char *) kalloc(sizeof(unsigned char) * NUM_CACHE_ENTRIES);
+
+ if (file_ids == NULL || access == NULL || (map_size != 0 && bitmap == NULL) || cache.acache == NULL || cache.haveaccess == NULL) {
+ if (file_ids) {
+ kfree(file_ids, sizeof(int) * num_files);
+ }
+ if (bitmap) {
+ kfree(bitmap, sizeof(char) * map_size);
+ }
+ if (access) {
+ kfree(access, sizeof(short) * num_files);
+ }
+ if (cache.acache) {
+ kfree(cache.acache, sizeof(int) * NUM_CACHE_ENTRIES);
+ }
+ if (cache.haveaccess) {
+ kfree(cache.haveaccess, sizeof(unsigned char) * NUM_CACHE_ENTRIES);
+ }
+ if (parents) {
+ kfree(parents, sizeof(cnid_t) * num_parents);
+ }
+ return ENOMEM;
+ }
+
+ // make sure the bitmap is zero'ed out...
+ if (bitmap) {
+ bzero(bitmap, (sizeof(char) * map_size));
+ }
+
+ if ((error = copyin(user_access_structp->file_ids, (caddr_t)file_ids,
+ num_files * sizeof(int)))) {
+ goto err_exit_bulk_access;
+ }
+
+ if (num_parents) {
+ if ((error = copyin(user_access_structp->parents, (caddr_t)parents,
+ num_parents * sizeof(cnid_t)))) {
+ goto err_exit_bulk_access;
+ }
+ }
+
+ flags = user_access_structp->flags;
+ if ((flags & (F_OK | R_OK | W_OK | X_OK)) == 0) {
+ flags = R_OK;
+ }
+
+ /* check if we've been passed leaf node ids or parent ids */
+ if (flags & PARENT_IDS_FLAG) {
+ check_leaf = false;
+ }
+
+ /* Check access to each file_id passed in */
+ for (i = 0; i < num_files; i++) {
+ leaf_index=-1;
+ cnid = (cnid_t) file_ids[i];
+
+ /* root always has access */
+ if ((!parents) && (!suser(cred, NULL))) {
+ access[i] = 0;
+ continue;
+ }
+
+ if (check_leaf) {
+ /* do the lookup (checks the cnode hash, then the catalog) */
+ error = do_attr_lookup(hfsmp, &cache, cnid, skip_cp, &catkey, &cnattr);
+ if (error) {
+ access[i] = (short) error;
+ continue;
+ }
+
+ if (parents) {
+ // Check if the leaf matches one of the parent scopes
+ leaf_index = cache_binSearch(parents, num_parents-1, cnid, NULL);
+ if (leaf_index >= 0 && parents[leaf_index] == cnid)
+ prev_parent_check_ok = 0;
+ else if (leaf_index >= 0)
+ prev_parent_check_ok = 1;
+ }
+
+ // if the thing has acl's, do the full permission check
+ if ((cnattr.ca_recflags & kHFSHasSecurityMask) != 0) {
+ struct vnode *cvp;
+ int myErr = 0;
+ /* get the vnode for this cnid */
+ myErr = hfs_vget(hfsmp, cnid, &cvp, 0);
+ if ( myErr ) {
+ access[i] = myErr;
+ continue;
+ }
+
+ hfs_unlock(VTOC(cvp));
+
+ if (vnode_vtype(cvp) == VDIR) {
+ myErr = vnode_authorize(cvp, NULL, (KAUTH_VNODE_SEARCH | KAUTH_VNODE_LIST_DIRECTORY), context);
+ } else {
+ myErr = vnode_authorize(cvp, NULL, KAUTH_VNODE_READ_DATA, context);
+ }
+
+ vnode_put(cvp);
+ if (myErr) {
+ access[i] = myErr;
+ continue;
+ }
+ } else {
+ /* before calling CheckAccess(), check the target file for read access */
+ myPerms = DerivePermissionSummary(cnattr.ca_uid, cnattr.ca_gid,
+ cnattr.ca_mode, hfsmp->hfs_mp, cred, p);
+
+ /* fail fast if no access */
+ if ((myPerms & flags) == 0) {
+ access[i] = EACCES;
+ continue;
+ }
+ }
+ } else {
+ /* we were passed an array of parent ids */
+ catkey.hfsPlus.parentID = cnid;
+ }
+
+ /* if the last guy had the same parent and had access, we're done */
+ if (i > 0 && catkey.hfsPlus.parentID == prevParent_cnid && access[i-1] == 0 && prev_parent_check_ok) {
+ cache.cachehits++;
+ access[i] = 0;
+ continue;
+ }
+
+ myaccess = do_access_check(hfsmp, &error, &cache, catkey.hfsPlus.parentID,
+ skip_cp, p, cred, context,bitmap, map_size, parents, num_parents);
+
+ if (myaccess || (error == ESRCH && leaf_index != -1)) {
+ access[i] = 0; // have access.. no errors to report
+ } else {
+ access[i] = (error != 0 ? (short) error : EACCES);
+ }
+
+ prevParent_cnid = catkey.hfsPlus.parentID;
+ }
+
+ /* copyout the access array */
+ if ((error = copyout((caddr_t)access, user_access_structp->access,
+ num_files * sizeof (short)))) {
+ goto err_exit_bulk_access;
+ }
+ if (map_size && bitmap) {
+ if ((error = copyout((caddr_t)bitmap, user_access_structp->bitmap,
+ map_size * sizeof (char)))) {
+ goto err_exit_bulk_access;
+ }
+ }
+
+
+ err_exit_bulk_access:
+
+ //printf("hfs: on exit (err %d), numfiles/numcached/cachehits/lookups is %d/%d/%d/%d\n", error, num_files, cache.numcached, cache.cachehits, cache.lookups);
+
+ if (file_ids)
+ kfree(file_ids, sizeof(int) * num_files);
+ if (parents)
+ kfree(parents, sizeof(cnid_t) * num_parents);
+ if (bitmap)
+ kfree(bitmap, sizeof(char) * map_size);
+ if (access)
+ kfree(access, sizeof(short) * num_files);
+ if (cache.acache)
+ kfree(cache.acache, sizeof(int) * NUM_CACHE_ENTRIES);
+ if (cache.haveaccess)
+ kfree(cache.haveaccess, sizeof(unsigned char) * NUM_CACHE_ENTRIES);
+
+ return (error);
+}
+
+
+/* end "bulk-access" support */
projects / apple / xnu.git / blobdiff