xref: /freebsd/sys/contrib/openzfs/module/zfs/zfs_byteswap.c (revision 22649d4dba730d46244fd2dff4fd174903c8379f)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * This file and its contents are supplied under the terms of the
4  * Common Development and Distribution License ("CDDL"), version 1.0.
5  * You may only use this file in accordance with the terms of version
6  * 1.0 of the CDDL.
7  *
8  * A full copy of the text of the CDDL should have accompanied this
9  * source.  A copy of the CDDL is also available via the Internet at
10  * https://opensource.org/license/CDDL-1.0.
11  */
12 /*
13  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
14  * Use is subject to license terms.
15  */
16 
17 #include <sys/zfs_context.h>
18 #include <sys/vfs.h>
19 #include <sys/fs/zfs.h>
20 #include <sys/zfs_znode.h>
21 #include <sys/zfs_sa.h>
22 #include <sys/zfs_acl.h>
23 
24 #ifndef _KERNEL
25 static
26 #endif
27 void
zfs_oldace_byteswap(ace_t * ace,int ace_cnt)28 zfs_oldace_byteswap(ace_t *ace, int ace_cnt)
29 {
30 	for (int i = 0; i != ace_cnt; i++, ace++) {
31 		ace->a_who = BSWAP_32(ace->a_who);
32 		ace->a_access_mask = BSWAP_32(ace->a_access_mask);
33 		ace->a_flags = BSWAP_16(ace->a_flags);
34 		ace->a_type = BSWAP_16(ace->a_type);
35 	}
36 }
37 
38 /*
39  * swap ace_t and ace_object_t
40  */
41 #ifndef _KERNEL
42 static
43 #endif
44 void
zfs_ace_byteswap(void * buf,size_t size,boolean_t zfs_layout)45 zfs_ace_byteswap(void *buf, size_t size, boolean_t zfs_layout)
46 {
47 	caddr_t end;
48 	caddr_t ptr;
49 	zfs_ace_t *zacep = NULL;
50 	ace_t *acep;
51 	uint16_t entry_type;
52 	size_t entry_size;
53 	int ace_type;
54 
55 	end = (caddr_t)buf + size;
56 	ptr = buf;
57 
58 	while (ptr < end) {
59 		if (zfs_layout) {
60 			/*
61 			 * Avoid overrun.  Embedded aces can have one
62 			 * of several sizes.  We don't know exactly
63 			 * how many our present, only the size of the
64 			 * buffer containing them.  That size may be
65 			 * larger than needed to hold the aces
66 			 * present.  As long as we do not do any
67 			 * swapping beyond the end of our block we are
68 			 * okay.  It is safe to swap any non-ace data
69 			 * within the block since it is just zeros.
70 			 */
71 			if (ptr + sizeof (zfs_ace_hdr_t) > end) {
72 				break;
73 			}
74 			zacep = (zfs_ace_t *)ptr;
75 			zacep->z_hdr.z_access_mask =
76 			    BSWAP_32(zacep->z_hdr.z_access_mask);
77 			zacep->z_hdr.z_flags = BSWAP_16(zacep->z_hdr.z_flags);
78 			ace_type = zacep->z_hdr.z_type =
79 			    BSWAP_16(zacep->z_hdr.z_type);
80 			entry_type = zacep->z_hdr.z_flags & ACE_TYPE_FLAGS;
81 		} else {
82 			/* Overrun avoidance */
83 			if (ptr + sizeof (ace_t) > end) {
84 				break;
85 			}
86 			acep = (ace_t *)ptr;
87 			acep->a_access_mask = BSWAP_32(acep->a_access_mask);
88 			acep->a_flags = BSWAP_16(acep->a_flags);
89 			ace_type = acep->a_type = BSWAP_16(acep->a_type);
90 			acep->a_who = BSWAP_32(acep->a_who);
91 			entry_type = acep->a_flags & ACE_TYPE_FLAGS;
92 		}
93 		switch (entry_type) {
94 		case ACE_OWNER:
95 		case ACE_EVERYONE:
96 		case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
97 			entry_size = zfs_layout ?
98 			    sizeof (zfs_ace_hdr_t) : sizeof (ace_t);
99 			break;
100 		case ACE_IDENTIFIER_GROUP:
101 		default:
102 			/* Overrun avoidance */
103 			if (zfs_layout) {
104 				if (ptr + sizeof (zfs_ace_t) <= end) {
105 					zacep->z_fuid = BSWAP_64(zacep->z_fuid);
106 				} else {
107 					entry_size = sizeof (zfs_ace_t);
108 					break;
109 				}
110 			}
111 			switch (ace_type) {
112 			case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
113 			case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
114 			case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
115 			case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
116 				entry_size = zfs_layout ?
117 				    sizeof (zfs_object_ace_t) :
118 				    sizeof (ace_object_t);
119 				break;
120 			default:
121 				entry_size = zfs_layout ? sizeof (zfs_ace_t) :
122 				    sizeof (ace_t);
123 				break;
124 			}
125 		}
126 		ptr = ptr + entry_size;
127 	}
128 }
129 
130 void
zfs_oldacl_byteswap(void * buf,size_t size)131 zfs_oldacl_byteswap(void *buf, size_t size)
132 {
133 	/*
134 	 * Arggh, since we don't know how many ACEs are in
135 	 * the array, we have to swap the entire block
136 	 */
137 	zfs_oldace_byteswap((ace_t *)buf, size / sizeof (ace_t));
138 }
139 
140 void
zfs_acl_byteswap(void * buf,size_t size)141 zfs_acl_byteswap(void *buf, size_t size)
142 {
143 	zfs_ace_byteswap(buf, size, B_TRUE);
144 }
145 
146 void
zfs_znode_byteswap(void * buf,size_t size)147 zfs_znode_byteswap(void *buf, size_t size)
148 {
149 	znode_phys_t *zp = buf;
150 
151 	ASSERT(size >= sizeof (znode_phys_t));
152 
153 	zp->zp_crtime[0] = BSWAP_64(zp->zp_crtime[0]);
154 	zp->zp_crtime[1] = BSWAP_64(zp->zp_crtime[1]);
155 	zp->zp_atime[0] = BSWAP_64(zp->zp_atime[0]);
156 	zp->zp_atime[1] = BSWAP_64(zp->zp_atime[1]);
157 	zp->zp_mtime[0] = BSWAP_64(zp->zp_mtime[0]);
158 	zp->zp_mtime[1] = BSWAP_64(zp->zp_mtime[1]);
159 	zp->zp_ctime[0] = BSWAP_64(zp->zp_ctime[0]);
160 	zp->zp_ctime[1] = BSWAP_64(zp->zp_ctime[1]);
161 	zp->zp_gen = BSWAP_64(zp->zp_gen);
162 	zp->zp_mode = BSWAP_64(zp->zp_mode);
163 	zp->zp_size = BSWAP_64(zp->zp_size);
164 	zp->zp_parent = BSWAP_64(zp->zp_parent);
165 	zp->zp_links = BSWAP_64(zp->zp_links);
166 	zp->zp_xattr = BSWAP_64(zp->zp_xattr);
167 	zp->zp_rdev = BSWAP_64(zp->zp_rdev);
168 	zp->zp_flags = BSWAP_64(zp->zp_flags);
169 	zp->zp_uid = BSWAP_64(zp->zp_uid);
170 	zp->zp_gid = BSWAP_64(zp->zp_gid);
171 	zp->zp_zap = BSWAP_64(zp->zp_zap);
172 	zp->zp_pad[0] = BSWAP_64(zp->zp_pad[0]);
173 	zp->zp_pad[1] = BSWAP_64(zp->zp_pad[1]);
174 	zp->zp_pad[2] = BSWAP_64(zp->zp_pad[2]);
175 
176 	zp->zp_acl.z_acl_extern_obj = BSWAP_64(zp->zp_acl.z_acl_extern_obj);
177 	zp->zp_acl.z_acl_size = BSWAP_32(zp->zp_acl.z_acl_size);
178 	zp->zp_acl.z_acl_version = BSWAP_16(zp->zp_acl.z_acl_version);
179 	zp->zp_acl.z_acl_count = BSWAP_16(zp->zp_acl.z_acl_count);
180 	if (zp->zp_acl.z_acl_version == ZFS_ACL_VERSION) {
181 		zfs_acl_byteswap((void *)&zp->zp_acl.z_ace_data[0],
182 		    ZFS_ACE_SPACE);
183 	} else {
184 		zfs_oldace_byteswap((ace_t *)&zp->zp_acl.z_ace_data[0],
185 		    ACE_SLOT_CNT);
186 	}
187 }
188 
189 #if defined(_KERNEL)
190 EXPORT_SYMBOL(zfs_oldacl_byteswap);
191 EXPORT_SYMBOL(zfs_acl_byteswap);
192 EXPORT_SYMBOL(zfs_znode_byteswap);
193 #endif
194