xref: /aosp_15_r20/external/vboot_reference/firmware/2lib/include/2context.h (revision 8617a60d3594060b7ecbd21bc622a7c14f3cf2bc)
1 /* Copyright 2022 The ChromiumOS Authors
2  * Use of this source code is governed by a BSD-style license that can be
3  * found in the LICENSE file.
4  *
5  * Definition of the vb2_context structure and related constants.
6  */
7 
8 #ifndef VBOOT_REFERENCE_2CONTEXT_H_
9 #define VBOOT_REFERENCE_2CONTEXT_H_
10 
11 #include "2constants.h"
12 
13 /* Flags for vb2_context.
14  *
15  * Unless otherwise noted, flags are set by verified boot and may be read (but
16  * not set or cleared) by the caller.
17  */
18 enum vb2_context_flags {
19 
20 	/*
21 	 * Verified boot has changed nvdata[].  Caller must save nvdata[] back
22 	 * to its underlying storage, then may clear this flag.
23 	 */
24 	VB2_CONTEXT_NVDATA_CHANGED = (1 << 0),
25 
26 	/*
27 	 * Verified boot has changed secdata_firmware[].  Caller must save
28 	 * secdata_firmware[] back to its underlying storage, then may clear
29 	 * this flag.
30 	 */
31 	VB2_CONTEXT_SECDATA_FIRMWARE_CHANGED = (1 << 1),
32 
33 	/* Recovery mode is requested this boot */
34 	VB2_CONTEXT_RECOVERY_MODE = (1 << 2),
35 
36 	/* Developer mode is requested this boot */
37 	VB2_CONTEXT_DEVELOPER_MODE = (1 << 3),
38 
39 	/*
40 	 * Force recovery mode due to physical user request.  Caller may set
41 	 * this flag when initializing the context.
42 	 */
43 	VB2_CONTEXT_FORCE_RECOVERY_MODE = (1 << 4),
44 
45 	/*
46 	 * Force developer mode enabled.  Caller may set this flag when
47 	 * initializing the context.  Previously used for forcing developer
48 	 * mode with physical dev switch.
49 	 *
50 	 * Deprecated as part of chromium:942901.
51 	 */
52 	VB2_CONTEXT_DEPRECATED_FORCE_DEVELOPER_MODE = (1 << 5),
53 
54 	/* Using firmware slot B.  If this flag is clear, using slot A. */
55 	VB2_CONTEXT_FW_SLOT_B = (1 << 6),
56 
57 	/* RAM should be cleared by caller this boot */
58 	VB2_CONTEXT_CLEAR_RAM = (1 << 7),
59 
60 	/* Wipeout by the app should be requested. */
61 	VB2_CONTEXT_FORCE_WIPEOUT_MODE = (1 << 8),
62 
63 	/* Erase developer mode state if it is enabled. */
64 	VB2_CONTEXT_DISABLE_DEVELOPER_MODE = (1 << 9),
65 
66 	/*
67 	 * Verified boot has changed secdata_kernel[].  Caller must save
68 	 * secdata_kernel[] back to its underlying storage, then may clear
69 	 * this flag.
70 	 */
71 	VB2_CONTEXT_SECDATA_KERNEL_CHANGED = (1 << 10),
72 
73 	/*
74 	 * Allow kernel verification to roll forward the version in
75 	 * secdata_kernel[].  Caller may set this flag before calling
76 	 * vb2api_kernel_phase3().
77 	 */
78 	VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD = (1 << 11),
79 
80 	/*
81 	 * Boot optimistically: don't touch failure counters.  Caller may set
82 	 * this flag when initializing the context.
83 	 */
84 	VB2_CONTEXT_NOFAIL_BOOT = (1 << 12),
85 
86 	/*
87 	 * secdata is not ready this boot, but should be ready next boot.  It
88 	 * would like to reboot.  The decision whether to reboot or not must be
89 	 * deferred until vboot, because rebooting all the time before then
90 	 * could cause a device with malfunctioning secdata to get stuck in an
91 	 * unrecoverable crash loop.
92 	 */
93 	VB2_CONTEXT_SECDATA_WANTS_REBOOT = (1 << 13),
94 
95 	/*
96 	 * Boot is S3->S0 resume, not S5->S0 normal boot.  Caller may set this
97 	 * flag when initializing the context.
98 	 */
99 	VB2_CONTEXT_S3_RESUME = (1 << 14),
100 
101 	/*
102 	 * System supports EC software sync.  Caller may set this flag at any
103 	 * time before calling vb2api_kernel_phase2().
104 	 */
105 	VB2_CONTEXT_EC_SYNC_SUPPORTED = (1 << 15),
106 
107 	/*
108 	 * EC software sync is slow to update; warning screen should be
109 	 * displayed.  Caller may set this flag at any time before calling
110 	 * vb2api_kernel_phase2().
111 	 */
112 	VB2_CONTEXT_EC_SYNC_SLOW = (1 << 16),
113 
114 	/*
115 	 * EC firmware supports early firmware selection; two EC images exist,
116 	 * and EC may have already verified and jumped to EC-RW prior to EC
117 	 * software sync.  Deprecated as part of chromium:1038259.
118 	 */
119 	VB2_CONTEXT_DEPRECATED_EC_EFS = (1 << 17),
120 
121 	/*
122 	 * NV storage uses data format V2.  Data is size VB2_NVDATA_SIZE_V2,
123 	 * not VB2_NVDATA_SIZE.
124 	 *
125 	 * Caller must set this flag when initializing the context to use V2.
126 	 * (Vboot cannot infer the data size from the data itself, because the
127 	 * data provided by the caller could be uninitialized.)
128 	 */
129 	VB2_CONTEXT_NVDATA_V2 = (1 << 18),
130 
131 	/*
132 	 * Allow vendor data to be set via the vendor data ui.
133 	 *
134 	 * Deprecated with CL:2512740.
135 	 */
136 	VB2_CONTEXT_DEPRECATED_VENDOR_DATA_SETTABLE = (1 << 19),
137 
138 	/*
139 	 * Caller may set this before running vb2api_fw_phase1.  In this case,
140 	 * it means: "Display is available on this boot.  Please advertise
141 	 * as such to downstream vboot code and users."
142 	 *
143 	 * vboot may also set this before returning from vb2api_fw_phase1.
144 	 * In this case, it means: "Please initialize display so that it is
145 	 * available to downstream vboot code and users."  This is used when
146 	 * vboot encounters some internally-generated request for display
147 	 * support.
148 	 */
149 	VB2_CONTEXT_DISPLAY_INIT = (1 << 20),
150 
151 	/*
152 	 * Caller may set this before running vb2api_kernel_phase1.  It means
153 	 * that there is no FWMP on this system, and thus default values should
154 	 * be used instead.
155 	 *
156 	 * Caller should *not* set this when FWMP is available but invalid.
157 	 */
158 	VB2_CONTEXT_NO_SECDATA_FWMP = (1 << 21),
159 
160 	/*
161 	 * Enable detachable menu ui (volume up/down + power).
162 	 *
163 	 * Deprecated with CL:1975390.
164 	 */
165 	VB2_CONTEXT_DEPRECATED_DETACHABLE_UI = (1 << 22),
166 
167 	/*
168 	 * NO_BOOT means the OS is not allowed to boot. Only relevant for EFS2.
169 	 */
170 	VB2_CONTEXT_NO_BOOT = (1 << 23),
171 
172 	/*
173 	 * TRUSTED means EC is running an RO copy and PD isn't enabled. At
174 	 * least that was last known to the GSC. If EC RO is correctly behaving,
175 	 * it doesn't jump to RW when this flag is set.
176 	 */
177 	VB2_CONTEXT_EC_TRUSTED = (1 << 24),
178 
179 	/*
180 	 * Boot into developer mode is allowed by FWMP or GBB flags.
181 	 */
182 	VB2_CONTEXT_DEV_BOOT_ALLOWED = (1 << 25),
183 
184 	/*
185 	 * Boot into developer mode from external disk is allowed by nvdata,
186 	 * FWMP or GBB flags.
187 	 */
188 	VB2_CONTEXT_DEV_BOOT_EXTERNAL_ALLOWED = (1 << 26),
189 
190 	/*
191 	 * Boot into developer mode from alternate bootloader is allowed by
192 	 * nvdata, FWMP or GBB flags.
193 	 */
194 	VB2_CONTEXT_DEV_BOOT_ALTFW_ALLOWED = (1 << 27),
195 
196 	/*
197 	 * If this is set after kernel verification, caller should disable the
198 	 * TPM before jumping to kernel.
199 	 */
200 	VB2_CONTEXT_DISABLE_TPM = (1 << 28),
201 
202 	/*
203 	 * Indicates there is only one RW slot present. Caller should set this
204 	 * flag when initializing the context if the flash layout does not
205 	 * support two RW slots.
206 	 */
207 	VB2_CONTEXT_SLOT_A_ONLY = (1 << 29),
208 };
209 
210 /* Helper for aligning fields in vb2_context. */
211 #define VB2_PAD_STRUCT3(size, align, count) \
212 	uint8_t _pad##count[align - (((size - 1) % align) + 1)]
213 #define VB2_PAD_STRUCT2(size, align, count) VB2_PAD_STRUCT3(size, align, count)
214 #define VB2_PAD_STRUCT(size, align) VB2_PAD_STRUCT2(size, align, __COUNTER__)
215 
216 /*
217  * Context for firmware verification.  Pass this to all vboot APIs.
218  *
219  * Context is stored as part of vb2_shared_data, initialized with vb2api_init().
220  * Subsequent retrieval of the context object should be done by calling
221  * vb2api_reinit(), e.g. if switching firmware applications.
222  *
223  * The context struct can be seen as the "publicly accessible" portion of
224  * vb2_shared_data, and thus does not require its own magic and version fields.
225  */
226 struct vb2_context {
227 
228 	/**********************************************************************
229 	 * Fields caller must initialize before calling any API functions.
230 	 */
231 
232 	/*
233 	 * Flags; see vb2_context_flags.  Some flags may only be set by caller
234 	 * prior to calling vboot functions.
235 	 */
236 	uint64_t flags;
237 
238 	/*
239 	 * Non-volatile data.  Caller must fill this from some non-volatile
240 	 * location before calling vb2api_fw_phase1.  If the
241 	 * VB2_CONTEXT_NVDATA_CHANGED flag is set when a vb2api function
242 	 * returns, caller must save the data back to the non-volatile location
243 	 * and then clear the flag.
244 	 */
245 	uint8_t nvdata[VB2_NVDATA_SIZE_V2];
246 	VB2_PAD_STRUCT(VB2_NVDATA_SIZE_V2, 8);
247 
248 	/*
249 	 * Secure data for firmware verification stage.  Caller must fill this
250 	 * from some secure non-volatile location before calling
251 	 * vb2api_fw_phase1.  If the VB2_CONTEXT_SECDATA_FIRMWARE_CHANGED flag
252 	 * is set when a function returns, caller must save the data back to the
253 	 * secure non-volatile location and then clear the flag.
254 	 */
255 	uint8_t secdata_firmware[VB2_SECDATA_FIRMWARE_SIZE];
256 	VB2_PAD_STRUCT(VB2_SECDATA_FIRMWARE_SIZE, 8);
257 
258 	/**********************************************************************
259 	 * Fields caller must initialize before calling vb2api_kernel_phase1().
260 	 */
261 
262 	/*
263 	 * Secure data for kernel verification stage.  Caller must fill this
264 	 * from some secure non-volatile location before calling
265 	 * vb2api_kernel_phase1.  If the VB2_CONTEXT_SECDATA_KERNEL_CHANGED
266 	 * flag is set when a function returns, caller must save the data back
267 	 * to the secure non-volatile location and then clear the flag.
268 	 */
269 	uint8_t secdata_kernel[VB2_SECDATA_KERNEL_MAX_SIZE];
270 	VB2_PAD_STRUCT(VB2_SECDATA_KERNEL_MAX_SIZE, 8);
271 
272 	/*
273 	 * Firmware management parameters (FWMP) secure data.  Caller must fill
274 	 * this from some secure non-volatile location before calling
275 	 * vb2api_kernel_phase1.  Since FWMP is a variable-size space, caller
276 	 * should initially fill in VB2_SECDATA_FWMP_MIN_SIZE bytes, and call
277 	 * vb2_secdata_fwmp_check() to see whether more should be read.  If the
278 	 * VB2_CONTEXT_SECDATA_FWMP_CHANGED flag is set when a function
279 	 * returns, caller must save the data back to the secure non-volatile
280 	 * location and then clear the flag.
281 	 */
282 	uint8_t secdata_fwmp[VB2_SECDATA_FWMP_MAX_SIZE];
283 	VB2_PAD_STRUCT(VB2_SECDATA_FWMP_MAX_SIZE, 8);
284 
285 	/**********************************************************************
286 	 * Fields below added in struct version 3.1.
287 	 */
288 
289 	/*
290 	 * Mutually exclusive boot mode (from enum vb2_boot_mode).
291 	 * This constant is initialized after calling vb2api_fw_phase1().
292 	 */
293 	const uint8_t boot_mode;
294 };
295 
296 #endif  /* VBOOT_REFERENCE_2CONTEXT_H_ */
297