xref: /freebsd/sys/contrib/openzfs/module/zfs/zfs_byteswap.c (revision 271171e0d97b88ba2a7c3bf750c9672b484c1c13)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/zfs_context.h>
27 #include <sys/vfs.h>
28 #include <sys/fs/zfs.h>
29 #include <sys/zfs_znode.h>
30 #include <sys/zfs_sa.h>
31 #include <sys/zfs_acl.h>
32 
33 #ifndef _KERNEL
34 static
35 #endif
36 void
zfs_oldace_byteswap(ace_t * ace,int ace_cnt)37 zfs_oldace_byteswap(ace_t *ace, int ace_cnt)
38 {
39 	for (int i = 0; i != ace_cnt; i++, ace++) {
40 		ace->a_who = BSWAP_32(ace->a_who);
41 		ace->a_access_mask = BSWAP_32(ace->a_access_mask);
42 		ace->a_flags = BSWAP_16(ace->a_flags);
43 		ace->a_type = BSWAP_16(ace->a_type);
44 	}
45 }
46 
47 /*
48  * swap ace_t and ace_object_t
49  */
50 #ifndef _KERNEL
51 static
52 #endif
53 void
zfs_ace_byteswap(void * buf,size_t size,boolean_t zfs_layout)54 zfs_ace_byteswap(void *buf, size_t size, boolean_t zfs_layout)
55 {
56 	caddr_t end;
57 	caddr_t ptr;
58 	zfs_ace_t *zacep = NULL;
59 	ace_t *acep;
60 	uint16_t entry_type;
61 	size_t entry_size;
62 	int ace_type;
63 
64 	end = (caddr_t)buf + size;
65 	ptr = buf;
66 
67 	while (ptr < end) {
68 		if (zfs_layout) {
69 			/*
70 			 * Avoid overrun.  Embedded aces can have one
71 			 * of several sizes.  We don't know exactly
72 			 * how many our present, only the size of the
73 			 * buffer containing them.  That size may be
74 			 * larger than needed to hold the aces
75 			 * present.  As long as we do not do any
76 			 * swapping beyond the end of our block we are
77 			 * okay.  It is safe to swap any non-ace data
78 			 * within the block since it is just zeros.
79 			 */
80 			if (ptr + sizeof (zfs_ace_hdr_t) > end) {
81 				break;
82 			}
83 			zacep = (zfs_ace_t *)ptr;
84 			zacep->z_hdr.z_access_mask =
85 			    BSWAP_32(zacep->z_hdr.z_access_mask);
86 			zacep->z_hdr.z_flags = BSWAP_16(zacep->z_hdr.z_flags);
87 			ace_type = zacep->z_hdr.z_type =
88 			    BSWAP_16(zacep->z_hdr.z_type);
89 			entry_type = zacep->z_hdr.z_flags & ACE_TYPE_FLAGS;
90 		} else {
91 			/* Overrun avoidance */
92 			if (ptr + sizeof (ace_t) > end) {
93 				break;
94 			}
95 			acep = (ace_t *)ptr;
96 			acep->a_access_mask = BSWAP_32(acep->a_access_mask);
97 			acep->a_flags = BSWAP_16(acep->a_flags);
98 			ace_type = acep->a_type = BSWAP_16(acep->a_type);
99 			acep->a_who = BSWAP_32(acep->a_who);
100 			entry_type = acep->a_flags & ACE_TYPE_FLAGS;
101 		}
102 		switch (entry_type) {
103 		case ACE_OWNER:
104 		case ACE_EVERYONE:
105 		case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
106 			entry_size = zfs_layout ?
107 			    sizeof (zfs_ace_hdr_t) : sizeof (ace_t);
108 			break;
109 		case ACE_IDENTIFIER_GROUP:
110 		default:
111 			/* Overrun avoidance */
112 			if (zfs_layout) {
113 				if (ptr + sizeof (zfs_ace_t) <= end) {
114 					zacep->z_fuid = BSWAP_64(zacep->z_fuid);
115 				} else {
116 					entry_size = sizeof (zfs_ace_t);
117 					break;
118 				}
119 			}
120 			switch (ace_type) {
121 			case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
122 			case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
123 			case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
124 			case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
125 				entry_size = zfs_layout ?
126 				    sizeof (zfs_object_ace_t) :
127 				    sizeof (ace_object_t);
128 				break;
129 			default:
130 				entry_size = zfs_layout ? sizeof (zfs_ace_t) :
131 				    sizeof (ace_t);
132 				break;
133 			}
134 		}
135 		ptr = ptr + entry_size;
136 	}
137 }
138 
139 void
zfs_oldacl_byteswap(void * buf,size_t size)140 zfs_oldacl_byteswap(void *buf, size_t size)
141 {
142 	/*
143 	 * Arggh, since we don't know how many ACEs are in
144 	 * the array, we have to swap the entire block
145 	 */
146 	zfs_oldace_byteswap((ace_t *)buf, size / sizeof (ace_t));
147 }
148 
149 void
zfs_acl_byteswap(void * buf,size_t size)150 zfs_acl_byteswap(void *buf, size_t size)
151 {
152 	zfs_ace_byteswap(buf, size, B_TRUE);
153 }
154 
155 void
zfs_znode_byteswap(void * buf,size_t size)156 zfs_znode_byteswap(void *buf, size_t size)
157 {
158 	znode_phys_t *zp = buf;
159 
160 	ASSERT(size >= sizeof (znode_phys_t));
161 
162 	zp->zp_crtime[0] = BSWAP_64(zp->zp_crtime[0]);
163 	zp->zp_crtime[1] = BSWAP_64(zp->zp_crtime[1]);
164 	zp->zp_atime[0] = BSWAP_64(zp->zp_atime[0]);
165 	zp->zp_atime[1] = BSWAP_64(zp->zp_atime[1]);
166 	zp->zp_mtime[0] = BSWAP_64(zp->zp_mtime[0]);
167 	zp->zp_mtime[1] = BSWAP_64(zp->zp_mtime[1]);
168 	zp->zp_ctime[0] = BSWAP_64(zp->zp_ctime[0]);
169 	zp->zp_ctime[1] = BSWAP_64(zp->zp_ctime[1]);
170 	zp->zp_gen = BSWAP_64(zp->zp_gen);
171 	zp->zp_mode = BSWAP_64(zp->zp_mode);
172 	zp->zp_size = BSWAP_64(zp->zp_size);
173 	zp->zp_parent = BSWAP_64(zp->zp_parent);
174 	zp->zp_links = BSWAP_64(zp->zp_links);
175 	zp->zp_xattr = BSWAP_64(zp->zp_xattr);
176 	zp->zp_rdev = BSWAP_64(zp->zp_rdev);
177 	zp->zp_flags = BSWAP_64(zp->zp_flags);
178 	zp->zp_uid = BSWAP_64(zp->zp_uid);
179 	zp->zp_gid = BSWAP_64(zp->zp_gid);
180 	zp->zp_zap = BSWAP_64(zp->zp_zap);
181 	zp->zp_pad[0] = BSWAP_64(zp->zp_pad[0]);
182 	zp->zp_pad[1] = BSWAP_64(zp->zp_pad[1]);
183 	zp->zp_pad[2] = BSWAP_64(zp->zp_pad[2]);
184 
185 	zp->zp_acl.z_acl_extern_obj = BSWAP_64(zp->zp_acl.z_acl_extern_obj);
186 	zp->zp_acl.z_acl_size = BSWAP_32(zp->zp_acl.z_acl_size);
187 	zp->zp_acl.z_acl_version = BSWAP_16(zp->zp_acl.z_acl_version);
188 	zp->zp_acl.z_acl_count = BSWAP_16(zp->zp_acl.z_acl_count);
189 	if (zp->zp_acl.z_acl_version == ZFS_ACL_VERSION) {
190 		zfs_acl_byteswap((void *)&zp->zp_acl.z_ace_data[0],
191 		    ZFS_ACE_SPACE);
192 	} else {
193 		zfs_oldace_byteswap((ace_t *)&zp->zp_acl.z_ace_data[0],
194 		    ACE_SLOT_CNT);
195 	}
196 }
197 
198 #if defined(_KERNEL)
199 EXPORT_SYMBOL(zfs_oldacl_byteswap);
200 EXPORT_SYMBOL(zfs_acl_byteswap);
201 EXPORT_SYMBOL(zfs_znode_byteswap);
202 #endif
203