bsd/sys/cprotect.h

   1 /*
   2  * Copyright (c) 2009-2014 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 #if KERNEL_PRIVATE
  33
  34 #include <sys/cdefs.h>
  35 #include <sys/param.h>
  36 #include <sys/buf.h>
  37 #include <sys/kdebug.h>
  38 #include <crypto/aes.h>
  39 #include <stdbool.h>
  40
  41 __BEGIN_DECLS
  42
  43 #define CP_CODE(code) FSDBG_CODE(DBG_CONTENT_PROT, code)
  44 /*
  45  * Class DBG_FSYSTEM == 0x03
  46  * Subclass DBG_CONTENT_PROT == 0xCF
  47  * These debug codes are of the form 0x03CFzzzz
  48  */
  49
  50 enum {
  51         CPDBG_OFFSET_IO = CP_CODE(0),   /* 0x03CF0000 */
  52 };
  53
  54 /* normally the debug events are no-ops */
  55 #define CP_DEBUG(x,a,b,c,d,e) do {} while (0);
  56
  57 /* dev kernels only! */
  58 #if !SECURE_KERNEL
  59
  60 /* KDEBUG events used by content protection subsystem */
  61 #if 0
  62 #undef CP_DEBUG
  63 #define CP_DEBUG KERNEL_DEBUG_CONSTANT
  64 #endif
  65
  66 #endif
  67
  68 #define CP_MAX_WRAPPEDKEYSIZE     128   /* The size of the largest allowed key */
  69
  70 /* lock events from AppleKeyStore */
  71 #define CP_LOCKED_STATE           0     /* Device is locked */
  72 #define CP_UNLOCKED_STATE         1     /* Device is unlocked */
  73
  74 #define CP_MAX_STATE                      1     /* uint8_t ; maximum # of states is 255 */
  75
  76 typedef struct cprotect *cprotect_t;
  77 typedef struct cp_wrap_func *cp_wrap_func_t;
  78 typedef struct cpx *cpx_t;
  79
  80 /* Structures passed between HFS and AKS kext */
  81 typedef struct {
  82         void     *key;
  83         unsigned key_len;
  84         void     *iv_key;
  85         unsigned iv_key_len;
  86         uint32_t flags;
  87 } cp_raw_key_s;
  88
  89 typedef cp_raw_key_s* cp_raw_key_t;
  90
  91 typedef struct {
  92         void     *key;
  93         unsigned key_len;
  94         uint32_t dp_class;
  95 } cp_wrapped_key_s;
  96
  97 typedef cp_wrapped_key_s* cp_wrapped_key_t;
  98
  99 typedef uint16_t cp_key_revision_t;
 100
 101 typedef struct {
 102         ino64_t                         inode;
 103         uint32_t                        volume;
 104         pid_t                           pid;
 105         uid_t                           uid;
 106         cp_key_revision_t       key_revision;
 107 } cp_cred_s;
 108
 109 typedef cp_cred_s* cp_cred_t;
 110
 111 /* The wrappers are invoked on the AKS kext */
 112 typedef int unwrapper_t(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in, cp_raw_key_t key_out);
 113 typedef int rewrapper_t(cp_cred_t access, uint32_t dp_class, const cp_wrapped_key_t wrapped_key_in, cp_wrapped_key_t wrapped_key_out);
 114 typedef int new_key_t(cp_cred_t access, uint32_t dp_class, cp_raw_key_t key_out, cp_wrapped_key_t wrapped_key_out);
 115 typedef int invalidater_t(cp_cred_t access); /* invalidates keys */
 116 typedef int backup_key_t(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in, cp_wrapped_key_t wrapped_key_out);
 117
 118
 119 /*
 120  * Flags for Interaction between AKS / Kernel
 121  * These are twiddled via the input/output structs in the above
 122  * wrapper/unwrapper functions.
 123  */
 124 #define CP_RAW_KEY_WRAPPEDKEY   0x00000001
 125
 126 /*
 127  * Function prototypes for kexts to interface with our internal cprotect
 128  * fields;  cpx provides opacity and allows us to modify behavior internally
 129  * without requiring kext changes.
 130  */
 131 cpx_t cpx_alloc(size_t key_size);
 132 void cpx_free(cpx_t);
 133 __attribute__((const)) size_t cpx_size(size_t key_size);
 134 __attribute__((pure)) bool cpx_is_sep_wrapped_key(const struct cpx *);
 135 void cpx_set_is_sep_wrapped_key(struct cpx *, bool);
 136 __attribute__((pure)) bool cpx_use_offset_for_iv(const struct cpx *);
 137 void cpx_set_use_offset_for_iv(struct cpx *, bool);
 138 __attribute__((pure)) uint16_t cpx_key_len(const struct cpx *);
 139 void cpx_set_key_len(struct cpx *, uint16_t key_len);
 140 __attribute__((pure)) void *cpx_key(const struct cpx *);
 141 aes_encrypt_ctx *cpx_iv_aes_ctx(struct cpx *);
 142
 143 /* Structure to store pointers for AKS functions */
 144 struct cp_wrap_func {
 145         new_key_t       *new_key;
 146         unwrapper_t     *unwrapper;
 147         rewrapper_t     *rewrapper;
 148         invalidater_t   *invalidater;
 149         backup_key_t    *backup_key;
 150 };
 151
 152 int cp_key_store_action(int);
 153 int cp_register_wraps(cp_wrap_func_t);
 154
 155 #ifdef BSD_KERNEL_PRIVATE
 156
 157 /*
 158  * Declarations that are not exported from the kernel but are used by
 159  * VFS to call into the implementation (i.e. HFS) should be here.
 160  */
 161
 162 /* Content Protection VNOP Operation flags */
 163 #define CP_READ_ACCESS            0x1
 164 #define CP_WRITE_ACCESS           0x2
 165
 166 /*
 167  * Functions to check the status of a CP and to query
 168  * the containing filesystem to see if it is supported.
 169  */
 170 struct vnode;
 171 struct hfsmount;
 172
 173 int cp_vnode_getclass(struct vnode *, int *);
 174 int cp_vnode_setclass(struct vnode *, uint32_t);
 175 int cp_vnode_transcode(struct vnode * vp, void *key, unsigned *len);
 176
 177 int cp_handle_vnop(struct vnode *, int, int);
 178 int cp_handle_open(struct vnode *vp, int mode);
 179 int cp_get_root_major_vers (struct vnode *vp, uint32_t *level);
 180 int cp_get_default_level (struct vnode *vp, uint32_t *level);
 181 int cp_is_valid_class (int isdir, int32_t protectionclass);
 182 int cp_set_trimmed(struct hfsmount *hfsmp);
 183 int cp_set_rewrapped(struct hfsmount *hfsmp);
 184 int cp_flop_generation (struct hfsmount *hfsmp);
 185
 186 #endif /* BSD_KERNEL_PRIVATE */
 187
 188 __END_DECLS
 189
 190 #endif /* KERNEL_PRIVATE */
 191 #endif /* !_SYS_CPROTECT_H_ */