1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 __FBSDID("$FreeBSD$"); 31 32 #include <errno.h> 33 #include <stdio.h> 34 #include <assert.h> 35 #include <sys/acl.h> 36 #include <sys/stat.h> 37 38 #include "acl_support.h" 39 40 /* 41 * These routines from sys/kern/subr_acl_nfs4.c are used by both kernel 42 * and libc. 43 */ 44 void acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp); 45 void acl_nfs4_trivial_from_mode_libc(struct acl *aclp, int file_owner_id, 46 int canonical_six); 47 48 static acl_t 49 _nfs4_acl_strip_np(const acl_t aclp, int canonical_six) 50 { 51 acl_t newacl; 52 mode_t mode = 0; 53 54 newacl = acl_init(ACL_MAX_ENTRIES); 55 if (newacl == NULL) { 56 errno = ENOMEM; 57 return (NULL); 58 } 59 60 _acl_brand_as(newacl, ACL_BRAND_NFS4); 61 62 acl_nfs4_sync_mode_from_acl(&mode, &(aclp->ats_acl)); 63 acl_nfs4_trivial_from_mode_libc(&(newacl->ats_acl), mode, canonical_six); 64 65 return (newacl); 66 } 67 68 static acl_t 69 _posix1e_acl_strip_np(const acl_t aclp, int recalculate_mask) 70 { 71 acl_t acl_new, acl_old; 72 acl_entry_t entry, entry_new; 73 acl_tag_t tag; 74 int entry_id, have_mask_entry; 75 76 assert(_acl_brand(aclp) == ACL_BRAND_POSIX); 77 78 acl_old = acl_dup(aclp); 79 if (acl_old == NULL) 80 return (NULL); 81 82 assert(_acl_brand(acl_old) == ACL_BRAND_POSIX); 83 84 have_mask_entry = 0; 85 acl_new = acl_init(ACL_MAX_ENTRIES); 86 if (acl_new == NULL) { 87 acl_free(acl_old); 88 return (NULL); 89 } 90 tag = ACL_UNDEFINED_TAG; 91 92 /* only save the default user/group/other entries */ 93 entry_id = ACL_FIRST_ENTRY; 94 while (acl_get_entry(acl_old, entry_id, &entry) == 1) { 95 entry_id = ACL_NEXT_ENTRY; 96 97 assert(_entry_brand(entry) == ACL_BRAND_POSIX); 98 99 if (acl_get_tag_type(entry, &tag) == -1) 100 goto fail; 101 102 switch(tag) { 103 case ACL_USER_OBJ: 104 case ACL_GROUP_OBJ: 105 case ACL_OTHER: 106 if (acl_create_entry(&acl_new, &entry_new) == -1) 107 goto fail; 108 if (acl_copy_entry(entry_new, entry) == -1) 109 goto fail; 110 assert(_entry_brand(entry_new) == ACL_BRAND_POSIX); 111 break; 112 case ACL_MASK: 113 have_mask_entry = 1; 114 break; 115 default: 116 break; 117 } 118 } 119 120 assert(_acl_brand(acl_new) == ACL_BRAND_POSIX); 121 122 if (have_mask_entry && recalculate_mask) { 123 if (acl_calc_mask(&acl_new) == -1) 124 goto fail; 125 } 126 127 return (acl_new); 128 129 fail: 130 acl_free(acl_new); 131 acl_free(acl_old); 132 133 return (NULL); 134 } 135 136 acl_t 137 acl_strip_np(const acl_t aclp, int recalculate_mask) 138 { 139 switch (_acl_brand(aclp)) { 140 case ACL_BRAND_NFS4: 141 return (_nfs4_acl_strip_np(aclp, 0)); 142 143 case ACL_BRAND_POSIX: 144 return (_posix1e_acl_strip_np(aclp, recalculate_mask)); 145 146 default: 147 errno = EINVAL; 148 return (NULL); 149 } 150 } 151 152 /* 153 * Return 1, if ACL is trivial, 0 otherwise. 154 * 155 * ACL is trivial, iff its meaning could be fully expressed using just file 156 * mode. In other words, ACL is trivial iff it doesn't have "+" to the right 157 * of the mode bits in "ls -l" output ;-) 158 */ 159 int 160 acl_is_trivial_np(const acl_t aclp, int *trivialp) 161 { 162 acl_t tmpacl; 163 int differs; 164 165 if (aclp == NULL || trivialp == NULL) { 166 errno = EINVAL; 167 return (-1); 168 } 169 170 switch (_acl_brand(aclp)) { 171 case ACL_BRAND_POSIX: 172 if (aclp->ats_acl.acl_cnt == 3) 173 *trivialp = 1; 174 else 175 *trivialp = 0; 176 177 return (0); 178 179 case ACL_BRAND_NFS4: 180 /* 181 * If the ACL has more than canonical six entries, 182 * it's non trivial by definition. 183 */ 184 if (aclp->ats_acl.acl_cnt > 6) { 185 *trivialp = 0; 186 return (0); 187 } 188 189 /* 190 * Calculate trivial ACL - using acl_strip_np(3) - and compare 191 * with the original. 192 */ 193 tmpacl = _nfs4_acl_strip_np(aclp, 0); 194 if (tmpacl == NULL) 195 return (-1); 196 197 differs = _acl_differs(aclp, tmpacl); 198 acl_free(tmpacl); 199 200 if (differs == 0) { 201 *trivialp = 1; 202 return (0); 203 } 204 205 /* 206 * Try again with an old-style, "canonical six" trivial ACL. 207 */ 208 tmpacl = _nfs4_acl_strip_np(aclp, 1); 209 if (tmpacl == NULL) 210 return (-1); 211 212 differs = _acl_differs(aclp, tmpacl); 213 acl_free(tmpacl); 214 215 if (differs) 216 *trivialp = 0; 217 else 218 *trivialp = 1; 219 220 return (0); 221 222 default: 223 errno = EINVAL; 224 return (-1); 225 } 226 } 227