1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2001-2002 Chris D. Faulhaber 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/types.h> 30 #include "namespace.h" 31 #include <sys/acl.h> 32 #include "un-namespace.h" 33 34 #include <errno.h> 35 #include <stdio.h> 36 37 #include "acl_support.h" 38 39 /* 40 * acl_calc_mask() (23.4.2): calculate and set the permissions 41 * associated with the ACL_MASK ACL entry. If the ACL already 42 * contains an ACL_MASK entry, its permissions shall be 43 * overwritten; if not, one shall be added. 44 */ 45 int 46 acl_calc_mask(acl_t *acl_p) 47 { 48 struct acl *acl_int, *acl_int_new; 49 acl_t acl_new; 50 int i, mask_mode, mask_num; 51 52 /* 53 * (23.4.2.4) requires acl_p to point to a pointer to a valid ACL. 54 * Since one of the primary reasons to use this function would be 55 * to calculate the appropriate mask to obtain a valid ACL, we only 56 * perform sanity checks here and validate the ACL prior to 57 * returning. 58 */ 59 if (acl_p == NULL || *acl_p == NULL) { 60 errno = EINVAL; 61 return (-1); 62 } 63 64 if (!_acl_brand_may_be(*acl_p, ACL_BRAND_POSIX)) { 65 errno = EINVAL; 66 return (-1); 67 } 68 _acl_brand_as(*acl_p, ACL_BRAND_POSIX); 69 70 acl_int = &(*acl_p)->ats_acl; 71 if ((acl_int->acl_cnt < 3) || (acl_int->acl_cnt > ACL_MAX_ENTRIES)) { 72 errno = EINVAL; 73 return (-1); 74 } 75 76 acl_new = acl_dup(*acl_p); 77 if (acl_new == NULL) 78 return (-1); 79 acl_int_new = &acl_new->ats_acl; 80 81 mask_mode = 0; 82 mask_num = -1; 83 84 /* gather permissions and find a mask entry */ 85 for (i = 0; i < acl_int_new->acl_cnt; i++) { 86 switch(acl_int_new->acl_entry[i].ae_tag) { 87 case ACL_USER: 88 case ACL_GROUP: 89 case ACL_GROUP_OBJ: 90 mask_mode |= 91 acl_int_new->acl_entry[i].ae_perm & ACL_PERM_BITS; 92 break; 93 case ACL_MASK: 94 mask_num = i; 95 break; 96 } 97 } 98 99 /* if a mask entry already exists, overwrite the perms */ 100 if (mask_num != -1) 101 acl_int_new->acl_entry[mask_num].ae_perm = mask_mode; 102 else { 103 /* if no mask exists, check acl_cnt... */ 104 if (acl_int_new->acl_cnt == ACL_MAX_ENTRIES) { 105 errno = ENOMEM; 106 acl_free(acl_new); 107 return (-1); 108 } 109 /* ...and add the mask entry */ 110 acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_tag = ACL_MASK; 111 acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_id = 112 ACL_UNDEFINED_ID; 113 acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_perm = 114 mask_mode; 115 acl_int_new->acl_cnt++; 116 } 117 118 if (acl_valid(acl_new) == -1) { 119 errno = EINVAL; 120 acl_free(acl_new); 121 return (-1); 122 } 123 124 **acl_p = *acl_new; 125 acl_free(acl_new); 126 127 return (0); 128 } 129