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