xref: /xnu-10063.101.15/bsd/sys/trusted_execution_monitor.h (revision 94d3b452840153a99b38a3a9659680b2a006908e)
1 /*
2  * Copyright (c) 2022 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_LICENSE_HEADER_START@
5  *
6  * The contents of this file constitute Original Code as defined in and
7  * are subject to the Apple Public Source License Version 1.1 (the
8  * "License").  You may not use this file except in compliance with the
9  * License.  Please obtain a copy of the License at
10  * http://www.apple.com/publicsource and read it before using this file.
11  *
12  * This Original Code and all software distributed under the License are
13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
17  * License for the specific language governing rights and limitations
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20  * @APPLE_LICENSE_HEADER_END@
21  */
22 
23 #ifndef _SYS_CODE_SIGNING_TXM_H_
24 #define _SYS_CODE_SIGNING_TXM_H_
25 
26 #if CONFIG_SPTM
27 
28 #include <libkern/section_keywords.h>
29 #include <kern/locks.h>
30 #include <kern/lock_rw.h>
31 #include <vm/pmap.h>
32 #include <sys/queue.h>
33 #include <TrustedExecutionMonitor/API.h>
34 
35 #ifndef kTXMImage4APIVersion
36 #define kTXMImage4APIVersion 0
37 #endif
38 
39 /* These are hidden behind MACH_KERNEL_PRIVATE in other files */
40 typedef uint64_t pmap_paddr_t __kernel_ptr_semantics;
41 pmap_paddr_t kvtophys_nofail(vm_offset_t va);
42 
43 /*
44  * The runtime lock used to enforce concurrency on all trust cache operations
45  * within the kernel for TXM. This is needed because TXM only enforces concurrency
46  * through try-locks, which means the kernel also needs to enforce concurrency
47  * on its side in order to ensure the try-locks within TXM never fail.
48  */
49 extern decl_lck_rw_data(, txm_trust_cache_lck);
50 
51 /* Global read-only data of TXM */
52 extern const TXMReadOnlyData_t *txm_ro_data;
53 
54 /* Code signing configuration of TXM */
55 extern const CSConfig_t *txm_cs_config;
56 
57 /* All statistical data collected from TXM */
58 extern const TXMStatistics_t *txm_stats;
59 
60 /* All static trust cache information collected from TXM */
61 extern uint32_t num_static_trust_caches;
62 extern TCCapabilities_t static_trust_cache_capabilities0;
63 extern TCCapabilities_t static_trust_cache_capabilities1;
64 
65 typedef struct _txm_thread_stack {
66 	/* Virtual mapping of the thread stack page */
67 	uintptr_t thread_stack_papt;
68 
69 	/* Physical page used for the thread stack */
70 	uintptr_t thread_stack_phys;
71 
72 	/* Pointer to the thread stack structure on the thread stack page */
73 	TXMThreadStack_t *thread_stack_data;
74 
75 	/* Linkage for the singly-linked-list */
76 	SLIST_ENTRY(_txm_thread_stack) link;
77 } txm_thread_stack_t;
78 
79 typedef struct _txm_call {
80 	/* Input arguments */
81 	TXMKernelSelector_t selector;
82 	TXMReturnCode_t failure_code_silent;
83 	bool failure_fatal;
84 	bool failure_silent;
85 	bool skip_logs;
86 	uint32_t num_input_args;
87 	uint32_t num_output_args;
88 
89 	/* Output arguments */
90 	TXMReturn_t txm_ret;
91 	uint64_t num_return_words;
92 	uint64_t return_words[kTXMStackReturnWords];
93 } txm_call_t;
94 
95 /**
96  * The main function to use for calling into the TrustedExecutionMonitor. This
97  * function handles all the bits required, including allocation/deallocation of
98  * the thread stack pages, the CPU instructions required to reach TXM, and also
99  * going through the TXM buffer and capturing any logs left by the monitor.
100  */
101 kern_return_t
102 txm_kernel_call(
103 	txm_call_t *parameters, ...);
104 
105 /**
106  * Go through the TrustedExecutionMonitor logging buffer and print all the logs
107  * which TXM has added to it since the kernel last looked.
108  */
109 void
110 txm_print_logs(void);
111 
112 /**
113  * Pages which need to be locked down by the TrustedExecutionMonitor need to made
114  * owned by TXM. This function can be used to go through each physical page in a
115  * range and transfer it to the relevant TXM type.
116  */
117 void
118 txm_transfer_region(
119 	vm_address_t addr,
120 	vm_size_t size);
121 
122 /**
123  * As part of transferring a page to the TrustedExecutionMonitor, the range of
124  * memory is always made read-only. This function can be used to go through all
125  * of the mappings and make them read-write again. This can only be done when TXM
126  * has transferred control of the pages back to the kernel.
127  */
128 void
129 txm_reclaim_region(
130 	vm_address_t addr,
131 	vm_size_t size);
132 
133 /**
134  * Register an address space with the TrustedExecutionMonitor based on an address
135  * space ID. This needs to be done AFTER the SPTM has made its call into TXM for
136  * registering an address space ID otherwise the system will panic.
137  */
138 kern_return_t
139 txm_register_address_space(
140 	pmap_t pmap,
141 	uint16_t addr_space_id,
142 	TXMAddressSpaceFlags_t flags);
143 
144 /**
145  * Unregister an address space from the TrustedExecutionMonitor using the address
146  * space object which was previously returned from TXM. This needs to be done
147  * AFTER the SPTM has unregistered the address space ID from TXM otherwise the
148  * system will panic.
149  */
150 kern_return_t
151 txm_unregister_address_space(
152 	pmap_t pmap);
153 
154 #endif /* CONFIG_SPTM */
155 #endif /* _SYS_CODE_SIGNING_TXM_H_ */
156