/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2001-2002 Chris D. Faulhaber * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #if 0 __FBSDID("$FreeBSD: head/lib/libc/posix1e/acl_calc_mask.c 326193 2017-11-25 17:12:48Z pfg $"); #else __RCSID("$NetBSD: acl_calc_mask.c,v 1.1 2020/05/16 18:31:47 christos Exp $"); #endif #include "namespace.h" #include #include #include #include #include "acl_support.h" /* * acl_calc_mask() (23.4.2): calculate and set the permissions * associated with the ACL_MASK ACL entry. If the ACL already * contains an ACL_MASK entry, its permissions shall be * overwritten; if not, one shall be added. */ int acl_calc_mask(acl_t *acl_p) { struct acl *acl_int, *acl_int_new; acl_t acl_new; size_t i; int mask_mode, mask_num; /* * (23.4.2.4) requires acl_p to point to a pointer to a valid ACL. * Since one of the primary reasons to use this function would be * to calculate the appropriate mask to obtain a valid ACL, we only * perform sanity checks here and validate the ACL prior to * returning. */ if (acl_p == NULL || *acl_p == NULL) { errno = EINVAL; return (-1); } if (!_acl_brand_may_be(*acl_p, ACL_BRAND_POSIX)) { errno = EINVAL; return (-1); } _acl_brand_as(*acl_p, ACL_BRAND_POSIX); acl_int = &(*acl_p)->ats_acl; if ((acl_int->acl_cnt < 3) || (acl_int->acl_cnt > ACL_MAX_ENTRIES)) { errno = EINVAL; return (-1); } acl_new = acl_dup(*acl_p); if (acl_new == NULL) return (-1); acl_int_new = &acl_new->ats_acl; mask_mode = 0; mask_num = -1; /* gather permissions and find a mask entry */ for (i = 0; i < acl_int_new->acl_cnt; i++) { switch(acl_int_new->acl_entry[i].ae_tag) { case ACL_USER: case ACL_GROUP: case ACL_GROUP_OBJ: mask_mode |= acl_int_new->acl_entry[i].ae_perm & ACL_PERM_BITS; break; case ACL_MASK: mask_num = i; break; } } /* if a mask entry already exists, overwrite the perms */ if (mask_num != -1) acl_int_new->acl_entry[mask_num].ae_perm = mask_mode; else { /* if no mask exists, check acl_cnt... */ if (acl_int_new->acl_cnt == ACL_MAX_ENTRIES) { errno = ENOMEM; acl_free(acl_new); return (-1); } /* ...and add the mask entry */ acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_tag = ACL_MASK; acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_id = ACL_UNDEFINED_ID; acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_perm = mask_mode; acl_int_new->acl_cnt++; } if (acl_valid(acl_new) == -1) { errno = EINVAL; acl_free(acl_new); return (-1); } **acl_p = *acl_new; acl_free(acl_new); return (0); }