1/*
2 * Copyright (c) 2010 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#include <sys/cdefs.h>
30#include <stdbool.h>
31
32#include <IOKit/assert.h>
33#include <IOKit/system.h>
34#include <IOKit/IOLib.h>
35#include <IOKit/IOMemoryDescriptor.h>
36#include <IOKit/IOKitDebug.h>
37
38__BEGIN_DECLS
39
40#include <pexpert/pexpert.h>
41
42static volatile UInt32 alreadyFetched = 0;
43static IOMemoryDescriptor * newData;
44
45IOMemoryDescriptor *
46IOGetBootKeyStoreData(void);
47void
48IOSetKeyStoreData(IOMemoryDescriptor * data);
49
50// APFS
51static volatile UInt32 apfsKeyFetched = 0;
52static IOMemoryDescriptor* apfsKeyData = NULL;
53
54IOMemoryDescriptor* IOGetAPFSKeyStoreData();
55void IOSetAPFSKeyStoreData(IOMemoryDescriptor* data);
56
57__END_DECLS
58
59#if 1
60#define DEBG(fmt, args...) { kprintf(fmt, ## args); }
61#else
62#define DEBG(fmt, args...) {}
63#endif
64
65void
66IOSetKeyStoreData(IOMemoryDescriptor * data)
67{
68 newData = data;
69 alreadyFetched = 0;
70}
71
72IOMemoryDescriptor *
73IOGetBootKeyStoreData(void)
74{
75 IOMemoryDescriptor *memoryDescriptor;
76 boot_args *args = (boot_args *)PE_state.bootArgs;
77 IOOptionBits options;
78 IOAddressRange ranges;
79
80 if (!OSCompareAndSwap(0, 1, &alreadyFetched))
81 return (NULL);
82
83 if (newData)
84 {
85 IOMemoryDescriptor * data = newData;
86 newData = NULL;
87 return (data);
88 }
89
90 DEBG("%s: data at address %u size %u\n", __func__,
91 args->keyStoreDataStart,
92 args->keyStoreDataSize);
93
94 if (args->keyStoreDataStart == 0)
95 return (NULL);
96
97 ranges.address = args->keyStoreDataStart;
98 ranges.length = args->keyStoreDataSize;
99
100 options = kIODirectionInOut | kIOMemoryTypePhysical64 | kIOMemoryMapperNone;
101
102 memoryDescriptor = IOMemoryDescriptor::withOptions(&ranges,
103 1,
104 0,
105 NULL,
106 options);
107
108 DEBG("%s: memory descriptor %p\n", __func__, memoryDescriptor);
109
110 return memoryDescriptor;
111}
112
113// APFS volume key fetcher
114
115// Store in-memory key (could be used by IOHibernateDone)
116void
117IOSetAPFSKeyStoreData(IOMemoryDescriptor* data)
118{
119 // Do not allow re-fetching of the boot_args key by passing NULL here.
120 if (data != NULL)
121 {
122 apfsKeyData = data;
123 apfsKeyFetched = 0;
124 }
125}
126
127// Retrieve any key we may have (stored in boot_args or by Hibernate)
128IOMemoryDescriptor*
129IOGetAPFSKeyStoreData()
130{
131 // Check if someone got the key before us
132 if (!OSCompareAndSwap(0, 1, &apfsKeyFetched))
133 return NULL;
134
135 // Do we have in-memory key?
136 if (apfsKeyData)
137 {
138 IOMemoryDescriptor* data = apfsKeyData;
139 apfsKeyData = NULL;
140 return data;
141 }
142
143 // Looks like there was no in-memory key and it's the first call - try boot_args
144 boot_args* args = (boot_args*)PE_state.bootArgs;
145
146 DEBG("%s: data at address %u size %u\n", __func__, args->apfsDataStart, args->apfsDataSize);
147 if (args->apfsDataStart == 0)
148 return NULL;
149
150 // We have the key in the boot_args, create IOMemoryDescriptor for the blob
151 IOAddressRange ranges;
152 ranges.address = args->apfsDataStart;
153 ranges.length = args->apfsDataSize;
154
155 const IOOptionBits options = kIODirectionInOut | kIOMemoryTypePhysical64 | kIOMemoryMapperNone;
156
157 IOMemoryDescriptor* memoryDescriptor = IOMemoryDescriptor::withOptions(&ranges, 1, 0, NULL, options);
158 DEBG("%s: memory descriptor %p\n", __func__, memoryDescriptor);
159 return memoryDescriptor;
160}
161