1 /*
2 * Copyright (c) 2021 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 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
26 */
27 #ifndef _KCOV_KSANCOV_DATA_H_
28 #define _KCOV_KSANCOV_DATA_H_
29
30 #if KERNEL_PRIVATE
31
32 #if CONFIG_KSANCOV
33
34 /*
35 * Supported coverage modes.
36 */
37 typedef enum {
38 KS_MODE_NONE,
39 KS_MODE_TRACE,
40 KS_MODE_COUNTERS,
41 KS_MODE_STKSIZE,
42 KS_MODE_MAX
43 } ksancov_mode_t;
44
45 /*
46 * A header that is always present in every ksancov mode shared memory structure.
47 */
48 typedef struct ksancov_header {
49 uint32_t kh_magic;
50 _Atomic uint32_t kh_enabled;
51 } ksancov_header_t;
52
53 /*
54 * TRACE mode data structure.
55 */
56
57 /*
58 * All trace based tools share this structure.
59 */
60 typedef struct ksancov_trace {
61 ksancov_header_t kt_hdr; /* header (must be always first) */
62 uint32_t kt_maxent; /* Maximum entries in this shared buffer. */
63 _Atomic uint32_t kt_head; /* Pointer to the first unused element. */
64 uint64_t kt_entries[]; /* Trace entries in this buffer. */
65 } ksancov_trace_t;
66
67 /* PC tracing only records PCs */
68 typedef uintptr_t ksancov_trace_pc_ent_t;
69
70 /* STKSIZE tracing records PCs and stack size. */
71 typedef struct ksancov_trace_stksize_entry {
72 uintptr_t pc; /* PC */
73 uint32_t stksize; /* associated stack size */
74 } ksancov_trace_stksize_ent_t;
75
76 /*
77 * COUNTERS mode data structure.
78 */
79 typedef struct ksancov_counters {
80 ksancov_header_t kc_hdr;
81 uint32_t kc_nedges; /* total number of edges */
82 uint8_t kc_hits[]; /* hits on each edge (8bit saturating) */
83 } ksancov_counters_t;
84
85 /*
86 * Edge to PC mapping.
87 */
88 typedef struct ksancov_edgemap {
89 uint32_t ke_magic;
90 uint32_t ke_nedges;
91 uintptr_t ke_addrs[]; /* address of each edge relative to 'offset' */
92 } ksancov_edgemap_t;
93
94 /*
95 * Supported comparison logging modes.
96 */
97 typedef enum {
98 KS_CMPS_MODE_NONE,
99 KS_CMPS_MODE_TRACE,
100 KS_CMPS_MODE_TRACE_FUNC,
101 KS_CMPS_MODE_MAX
102 } ksancov_cmps_mode_t;
103
104 #define KSANCOV_CMPS_TRACE_FUNC_MAX_BYTES 512
105
106 /* CMPS TRACE mode tracks comparison values */
107 typedef struct __attribute__((__packed__)) ksancov_cmps_trace_entry {
108 uint64_t pc;
109 uint32_t type;
110 uint16_t len1_func;
111 uint16_t len2_func;
112 union {
113 uint64_t args[2]; /* cmp instruction arguments */
114 uint8_t args_func[0]; /* cmp function arguments (variadic) */
115 };
116 } ksancov_cmps_trace_ent_t;
117
118 /* Calculate the total space that a ksancov_cmps_trace_ent_t tracing a function takes */
119 static inline size_t
ksancov_cmps_trace_func_space(size_t len1_func,size_t len2_func)120 ksancov_cmps_trace_func_space(size_t len1_func, size_t len2_func)
121 {
122 static_assert(sizeof(ksancov_cmps_trace_ent_t) == sizeof(uint64_t) * 3 + sizeof(uint32_t) + sizeof(uint16_t) * 2, "ksancov_cmps_trace_ent_t invalid size");
123
124 size_t size = sizeof(uint64_t) + sizeof(uint32_t) + sizeof(uint16_t) * 2; // header
125 size += len1_func + len2_func;
126 size_t rem = size % sizeof(ksancov_cmps_trace_ent_t);
127 if (rem == 0) {
128 return size;
129 }
130 return size + sizeof(ksancov_cmps_trace_ent_t) - rem;
131 }
132
133 static inline uint8_t *
ksancov_cmps_trace_func_arg1(ksancov_cmps_trace_ent_t * entry)134 ksancov_cmps_trace_func_arg1(ksancov_cmps_trace_ent_t *entry)
135 {
136 return entry->args_func;
137 }
138
139 static inline uint8_t *
ksancov_cmps_trace_func_arg2(ksancov_cmps_trace_ent_t * entry)140 ksancov_cmps_trace_func_arg2(ksancov_cmps_trace_ent_t *entry)
141 {
142 uint8_t* func_args = entry->args_func;
143 return &func_args[entry->len1_func];
144 }
145
146 #define KSANCOV_SERIALIZED_TESTCASE_BYTES 16777216 // 16MiB
147 #define KSANCOV_SERIALIZED_TESTCASES_MAX_COUNT 100
148
149 typedef struct ksancov_serialized_testcase {
150 uint32_t size;
151 uint8_t buffer[KSANCOV_SERIALIZED_TESTCASE_BYTES];
152 } ksancov_serialized_testcase_t;
153
154 /*
155 * Store the latest executed testcases in kernel to dump on panic.
156 */
157 typedef struct ksancov_serialized_testcases {
158 uint32_t head; /* current head of the circular buffer */
159 uint32_t inner_index; /* current inner index in the head testcase (e.g. current call being executed) */
160 ksancov_serialized_testcase_t list[]; /* testcases circular buffer */
161 } ksancov_serialized_testcases_t;
162
163 /*
164 * Represents state of a ksancov device when userspace asks for coverage data recording.
165 */
166
167 struct ksancov_dev {
168 ksancov_mode_t mode;
169
170 union {
171 ksancov_header_t *hdr;
172 ksancov_trace_t *trace;
173 ksancov_counters_t *counters;
174 };
175 size_t sz; /* size of allocated trace/counters buffer */
176
177 size_t maxpcs;
178
179 ksancov_cmps_mode_t cmps_mode;
180
181 union {
182 ksancov_header_t *cmps_hdr;
183 ksancov_trace_t *cmps_trace;
184 };
185 size_t cmps_sz; /* size of allocated cmps trace buffer */
186
187 ksancov_serialized_testcases_t* testcases;
188 uint32_t testcases_count; /* number of testcases in the buffer (less or equal than max count) */
189
190 thread_t thread;
191 dev_t dev;
192 lck_mtx_t lock;
193 };
194 typedef struct ksancov_dev * ksancov_dev_t;
195
196
197 #endif /* CONFIG_KSANCOV */
198
199 #endif /* KERNEL_PRIVATE */
200
201 #endif /* _KCOV_KSANCOV_DATA_H_ */
202