1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2001 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 THE 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/cdefs.h> 30 #if 0 31 __FBSDID("$FreeBSD: head/lib/libc/posix1e/acl_strip.c 344294 2019-02-19 19:15:15Z sef $"); 32 #else 33 __RCSID("$NetBSD: acl_strip.c,v 1.1 2020/05/16 18:31:47 christos Exp $"); 34 #endif 35 36 #include <errno.h> 37 #include <stdio.h> 38 #include <assert.h> 39 #include <sys/acl.h> 40 #include <sys/stat.h> 41 42 #include "acl_support.h" 43 44 static acl_t 45 _nfs4_acl_strip_np(const acl_t aclp, int canonical_six) 46 { 47 acl_t newacl; 48 mode_t mode = 0; 49 50 newacl = acl_init(ACL_MAX_ENTRIES); 51 if (newacl == NULL) { 52 errno = ENOMEM; 53 return (NULL); 54 } 55 56 _acl_brand_as(newacl, ACL_BRAND_NFS4); 57 58 __acl_nfs4_sync_mode_from_acl(&mode, &(aclp->ats_acl)); 59 __acl_nfs4_trivial_from_mode_libc(&(newacl->ats_acl), mode, canonical_six); 60 61 return (newacl); 62 } 63 64 static acl_t 65 _posix1e_acl_strip_np(const acl_t aclp, int recalculate_mask) 66 { 67 acl_t acl_new, acl_old; 68 acl_entry_t entry, entry_new; 69 acl_tag_t tag; 70 int entry_id, have_mask_entry; 71 72 assert(_acl_brand(aclp) == ACL_BRAND_POSIX); 73 74 acl_old = acl_dup(aclp); 75 if (acl_old == NULL) 76 return (NULL); 77 78 assert(_acl_brand(acl_old) == ACL_BRAND_POSIX); 79 80 have_mask_entry = 0; 81 acl_new = acl_init(ACL_MAX_ENTRIES); 82 if (acl_new == NULL) { 83 acl_free(acl_old); 84 return (NULL); 85 } 86 tag = ACL_UNDEFINED_TAG; 87 88 /* only save the default user/group/other entries */ 89 entry_id = ACL_FIRST_ENTRY; 90 while (acl_get_entry(acl_old, entry_id, &entry) == 1) { 91 entry_id = ACL_NEXT_ENTRY; 92 93 assert(_entry_brand(entry) == ACL_BRAND_POSIX); 94 95 if (acl_get_tag_type(entry, &tag) == -1) 96 goto fail; 97 98 switch(tag) { 99 case ACL_USER_OBJ: 100 case ACL_GROUP_OBJ: 101 case ACL_OTHER: 102 if (acl_create_entry(&acl_new, &entry_new) == -1) 103 goto fail; 104 if (acl_copy_entry(entry_new, entry) == -1) 105 goto fail; 106 assert(_entry_brand(entry_new) == ACL_BRAND_POSIX); 107 break; 108 case ACL_MASK: 109 have_mask_entry = 1; 110 break; 111 default: 112 break; 113 } 114 } 115 116 assert(_acl_brand(acl_new) == ACL_BRAND_POSIX); 117 118 if (have_mask_entry && recalculate_mask) { 119 if (acl_calc_mask(&acl_new) == -1) 120 goto fail; 121 } 122 123 return (acl_new); 124 125 fail: 126 acl_free(acl_new); 127 acl_free(acl_old); 128 129 return (NULL); 130 } 131 132 acl_t 133 acl_strip_np(const acl_t aclp, int recalculate_mask) 134 { 135 switch (_acl_brand(aclp)) { 136 case ACL_BRAND_NFS4: 137 return (_nfs4_acl_strip_np(aclp, 0)); 138 139 case ACL_BRAND_POSIX: 140 return (_posix1e_acl_strip_np(aclp, recalculate_mask)); 141 142 default: 143 errno = EINVAL; 144 return (NULL); 145 } 146 } 147 148 /* 149 * Return 1, if ACL is trivial, 0 otherwise. 150 * 151 * ACL is trivial, iff its meaning could be fully expressed using just file 152 * mode. In other words, ACL is trivial iff it doesn't have "+" to the right 153 * of the mode bits in "ls -l" output ;-) 154 */ 155 int 156 acl_is_trivial_np(const acl_t aclp, int *trivialp) 157 { 158 acl_t tmpacl; 159 int differs; 160 161 if (aclp == NULL || trivialp == NULL) { 162 errno = EINVAL; 163 return (-1); 164 } 165 166 switch (_acl_brand(aclp)) { 167 case ACL_BRAND_POSIX: 168 if (aclp->ats_acl.acl_cnt == 3) 169 *trivialp = 1; 170 else 171 *trivialp = 0; 172 173 return (0); 174 175 case ACL_BRAND_NFS4: 176 /* 177 * If the ACL has more than canonical six entries, 178 * it's non trivial by definition. 179 */ 180 if (aclp->ats_acl.acl_cnt > 6) { 181 *trivialp = 0; 182 return (0); 183 } 184 185 /* 186 * Calculate trivial ACL - using acl_strip_np(3) - and compare 187 * with the original. 188 */ 189 tmpacl = _nfs4_acl_strip_np(aclp, 0); 190 if (tmpacl == NULL) 191 return (-1); 192 193 differs = _acl_differs(aclp, tmpacl); 194 acl_free(tmpacl); 195 196 if (differs == 0) { 197 *trivialp = 1; 198 return (0); 199 } 200 201 /* 202 * Try again with an old-style, "canonical six" trivial ACL. 203 */ 204 tmpacl = _nfs4_acl_strip_np(aclp, 1); 205 if (tmpacl == NULL) 206 return (-1); 207 208 differs = _acl_differs(aclp, tmpacl); 209 acl_free(tmpacl); 210 211 if (differs) 212 *trivialp = 0; 213 else 214 *trivialp = 1; 215 216 return (0); 217 218 default: 219 errno = EINVAL; 220 return (-1); 221 } 222 } 223