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1/*
2 * Copyright (c) 2009 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29#ifndef _SYS_CPROTECT_H_
30#define _SYS_CPROTECT_H_
31
32#ifdef __cplusplus
33extern "C" {
34#endif
35
36#if KERNEL_PRIVATE
37
38#include <sys/cdefs.h>
39#include <sys/content_protection.h>
40#include <sys/kernel_types.h>
41#include <crypto/aes.h>
42
43#define CP_IV_KEYSIZE 20 /* 16x8 = 128, but SHA1 pushes 20 bytes so keep space for that */
44#define CP_MAX_KEYSIZE 32 /* 8x4 = 32, 32x8 = 256 */
45#define CP_MAX_WRAPPEDKEYSIZE 128 /* The size of the largest allowed key */
46#define CP_INITIAL_WRAPPEDKEYSIZE 40
47#define CP_V2_WRAPPEDKEYSIZE 40 /* Size of the wrapped key in a v2 EA */
48
49/* lock events from AppleKeyStore */
50#define CP_LOCKED_STATE 0 /* Device is locked */
51#define CP_UNLOCKED_STATE 1 /* Device is unlocked */
52
53#define CP_LOCKED_KEYCHAIN 0
54#define CP_UNLOCKED_KEYCHAIN 1
55
56/* For struct cprotect: cp_flags */
57#define CP_NEEDS_KEYS 0x1 /* File needs persistent keys */
58#define CP_KEY_FLUSHED 0x2 /* File's unwrapped key has been purged from memory */
59#define CP_NO_XATTR 0x4 /* Key info has not been saved as EA to the FS */
60#define CP_OFF_IV_ENABLED 0x8 /* Only go down relative IV route if this flag is set */
61
62#define CP_RELOCATION_INFLIGHT 0x10 /* File with offset IVs is in the process of being relocated. */
63
64/* Content Protection VNOP Operation flags */
65#define CP_READ_ACCESS 0x1
66#define CP_WRITE_ACCESS 0x2
67
68/*
69 * Check for this version when deciding to enable features
70 * For Apex, CP_CURRENT_MAJOR_VERS = 2.0
71 * For Telluride, CP_CURRENT_MAJOR_VERS = 4.0
72 */
73#define CONTENT_PROTECTION_XATTR_NAME "com.apple.system.cprotect"
74#define CP_NEW_MAJOR_VERS 4
75#define CP_PREV_MAJOR_VERS 2
76#define CP_MINOR_VERS 0
77
78typedef struct cprotect *cprotect_t;
79typedef struct cp_wrap_func *cp_wrap_func_t;
80typedef struct cp_global_state *cp_global_state_t;
81typedef struct cp_xattr *cp_xattr_t;
82
83typedef struct cnode * cnode_ptr_t;
84//forward declare the struct.
85struct hfsmount;
86
87/* The wrappers are invoked by the AKS kext */
88typedef int wrapper_t(uint32_t properties, uint64_t file_id, void *key_bytes, size_t key_length, void *wrapped_data, size_t *wrapped_length);
89typedef int unwrapper_t(uint32_t properties, void *wrapped_data, size_t wrapped_data_length, void *key_bytes, size_t *key_length);
90
91/*
92 * Runtime-only structure containing the content protection status
93 * for the given file. This is contained within the cnode
94 * This is passed down to IOStorageFamily via the bufattr struct
95 *
96 ******************************************************
97 * Some Key calculation information for offset based IV
98 ******************************************************
99 * Kf = original 256 bit per file key
100 * Kiv = SHA1(Kf), use full Kf, but truncate Kiv to 128 bits
101 * Kiv can be cached in the cprotect, so it only has to be calculated once for the file init
102 *
103 * IVb = Encrypt(Kiv, offset)
104 *
105 */
106struct cprotect {
107 uint32_t cp_flags;
108 uint32_t cp_pclass;
109 aes_encrypt_ctx cp_cache_iv_ctx;
110 uint32_t cp_cache_key_len;
111 uint8_t cp_cache_key[CP_MAX_KEYSIZE];
112 uint32_t cp_persistent_key_len;
113 uint8_t cp_persistent_key[];
114};
115
116struct cp_wrap_func {
117 wrapper_t *wrapper;
118 unwrapper_t *unwrapper;
119};
120
121struct cp_global_state {
122 uint8_t wrap_functions_set;
123 uint8_t lock_state;
124 u_int16_t reserved;
125};
126
127/*
128 * On-disk structure written as the per-file EA payload
129 * All on-disk multi-byte fields for the CP XATTR must be stored
130 * little-endian on-disk. This means they must be endian swapped to
131 * L.E on getxattr() and converted to LE on setxattr().
132 */
133struct cp_xattr_v2 {
134 u_int16_t xattr_major_version;
135 u_int16_t xattr_minor_version;
136 u_int32_t flags;
137 u_int32_t persistent_class;
138 u_int32_t key_size;
139 uint8_t persistent_key[CP_V2_WRAPPEDKEYSIZE];
140};
141
142struct cp_xattr_v4 {
143 u_int16_t xattr_major_version;
144 u_int16_t xattr_minor_version;
145 u_int32_t flags;
146 u_int32_t persistent_class;
147 u_int32_t key_size;
148 u_int32_t reserved1;
149 u_int32_t reserved2;
150 u_int32_t reserved3;
151 u_int32_t reserved4;
152 u_int32_t reserved5;
153 uint8_t persistent_key[CP_MAX_WRAPPEDKEYSIZE];
154};
155
156/* Same is true for the root EA, all fields must be written little endian. */
157struct cp_root_xattr {
158 u_int16_t major_version;
159 u_int16_t minor_version;
160 u_int64_t flags;
161 u_int32_t reserved1;
162 u_int32_t reserved2;
163 u_int32_t reserved3;
164 u_int32_t reserved4;
165};
166
167
168/*
169 * Functions to check the status of a CP and to query
170 * the containing filesystem to see if it is supported.
171 */
172int cp_vnode_getclass(vnode_t, int *);
173int cp_vnode_setclass(vnode_t, uint32_t);
174int cp_vnode_transcode(vnode_t);
175
176int cp_key_store_action(int);
177int cp_register_wraps(cp_wrap_func_t);
178
179int cp_entry_init(cnode_ptr_t, struct mount *);
180int cp_entry_create_keys(struct cprotect **entry_ptr, struct cnode *dcp, struct hfsmount *hfsmp,
181 uint32_t input_class, uint32_t fileid, mode_t cmode);
182int cp_entry_gentempkeys(struct cprotect **entry_ptr, struct hfsmount *hfsmp);
183void cp_entry_destroy(struct cprotect **entry_ptr);
184
185cnode_ptr_t cp_get_protected_cnode(vnode_t);
186int cp_handle_vnop(vnode_t, int, int);
187int cp_fs_protected (mount_t);
188int cp_getrootxattr (struct hfsmount *hfsmp, struct cp_root_xattr *outxattr);
189int cp_setrootxattr (struct hfsmount *hfsmp, struct cp_root_xattr *newxattr);
190int cp_setxattr(struct cnode *cp, struct cprotect *entry, struct hfsmount *hfsmp, uint32_t fileid, int options);
191int cp_update_mkb (struct cprotect *entry, uint32_t fileid);
192int cp_handle_relocate (cnode_ptr_t cp, struct hfsmount *hfsmp);
193int cp_handle_open(struct vnode *vp, int mode);
194int cp_get_root_major_vers (struct vnode *vp, uint32_t *level);
195
196#if 0
197int cp_isdevice_locked (void);
198#endif
199
200#endif /* KERNEL_PRIVATE */
201
202#ifdef __cplusplus
203};
204#endif
205
206#endif /* !_SYS_CPROTECT_H_ */