xref: /aosp_15_r20/external/vboot_reference/firmware/include/gpt_misc.h (revision 8617a60d3594060b7ecbd21bc622a7c14f3cf2bc)
1 /* Copyright 2013 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 
6 #ifndef VBOOT_REFERENCE_GPT_MISC_H_
7 #define VBOOT_REFERENCE_GPT_MISC_H_
8 
9 #include "gpt.h"
10 #include "vboot_api.h"
11 
12 #ifdef __cplusplus
13 extern "C" {
14 #endif  /* __cplusplus */
15 
16 enum {
17 	GPT_SUCCESS = 0,
18 	GPT_ERROR_NO_VALID_KERNEL,
19 	GPT_ERROR_INVALID_HEADERS,
20 	GPT_ERROR_INVALID_ENTRIES,
21 	GPT_ERROR_INVALID_SECTOR_SIZE,
22 	GPT_ERROR_INVALID_SECTOR_NUMBER,
23 	GPT_ERROR_INVALID_UPDATE_TYPE,
24 	GPT_ERROR_CRC_CORRUPTED,
25 	GPT_ERROR_OUT_OF_REGION,
26 	GPT_ERROR_START_LBA_OVERLAP,
27 	GPT_ERROR_END_LBA_OVERLAP,
28 	GPT_ERROR_DUP_GUID,
29 	GPT_ERROR_INVALID_FLASH_GEOMETRY,
30 	GPT_ERROR_NO_SUCH_ENTRY,
31 	/* Number of errors */
32 	GPT_ERROR_COUNT
33 };
34 
35 /* Bit masks for GptData.modified field. */
36 #define GPT_MODIFIED_HEADER1 0x01
37 #define GPT_MODIFIED_HEADER2 0x02
38 #define GPT_MODIFIED_ENTRIES1 0x04
39 #define GPT_MODIFIED_ENTRIES2 0x08
40 
41 /*
42  * The 'update_type' of GptUpdateKernelEntry().  We expose TRY and BAD only
43  * because those are what verified boot needs.  For more precise control on GPT
44  * attribute bits, please refer to gpt_internal.h.
45  */
46 enum {
47 	/*
48 	 * System will be trying to boot the currently selected kernel
49 	 * partition.  Update its try count if necessary.
50 	 */
51 	GPT_UPDATE_ENTRY_TRY = 1,
52 	/*
53 	 * The currently selected kernel partition failed validation.  Mark
54 	 * entry as invalid.
55 	 */
56 	GPT_UPDATE_ENTRY_BAD = 2,
57 	/*
58 	 * Used for fastboot mode. If kernel partition slot is marked active,
59 	 * its GPT entry is marked with S1,P2,T0.
60 	 */
61 	GPT_UPDATE_ENTRY_ACTIVE = 3,
62 	/*
63 	 * Used for fastboot mode. If kernel partition slot is marked invalid,
64 	 * its GPT entry is marked with S0,P0,T0.
65 	 */
66 	GPT_UPDATE_ENTRY_INVALID = 4,
67 };
68 
69 /* If this bit is 1, the GPT is stored in another from the streaming data */
70 #define GPT_FLAG_EXTERNAL	0x1
71 
72 /*
73  * A note about stored_on_device and gpt_drive_sectors:
74  *
75  * This code is used by both the "cgpt" utility and depthcharge/vboot. ATM,
76  * depthcharge does not have logic to properly setup stored_on_device and
77  * gpt_drive_sectors, but it does do a memset(gpt, 0, sizeof(GptData)). And so,
78  * GPT_STORED_ON_DEVICE should be 0 to make stored_on_device compatible with
79  * present behavior. At the same time, in vb2api_load_kernel() and GptLoad(),
80  * we need to have simple shims to set gpt_drive_sectors to drive_sectors.
81  *
82  * TODO(namnguyen): Remove those shims when the firmware can set these fields.
83  */
84 typedef struct {
85 	/* Fill in the following fields before calling GptInit() */
86 	/* GPT primary header, from sector 1 of disk (size: 512 bytes) */
87 	uint8_t *primary_header;
88 	/* GPT secondary header, from last sector of disk (size: 512 bytes) */
89 	uint8_t *secondary_header;
90 	/* Primary GPT table, follows primary header */
91 	uint8_t *primary_entries;
92 	/* Secondary GPT table, precedes secondary header */
93 	uint8_t *secondary_entries;
94 	/* Size of a LBA sector, in bytes */
95 	uint32_t sector_bytes;
96 	/* Size of drive (that the partitions are on) in LBA sectors */
97 	uint64_t streaming_drive_sectors;
98 	/* Size of the device that holds the GPT structures, 512-byte sectors */
99 	uint64_t gpt_drive_sectors;
100 	/* Flags */
101 	uint32_t flags;
102 
103 	/* Outputs */
104 	/* Which inputs have been modified?  GPT_MODIFIED_* */
105 	uint8_t modified;
106 	/*
107 	 * The current chromeos kernel index in partition table.  -1 means not
108 	 * found on drive. Note that GPT partition numbers are traditionally
109 	 * 1-based, but we're using a zero-based index here.
110 	 */
111 	int current_kernel;
112 
113 	/* Internal variables */
114 	uint8_t valid_headers, valid_entries, ignored;
115 	int current_priority;
116 } GptData;
117 
118 /**
119  * Initializes the GPT data structure's internal state.
120  *
121  * The following fields must be filled before calling this function:
122  *
123  *   primary_header
124  *   secondary_header
125  *   primary_entries
126  *   secondary_entries
127  *   sector_bytes
128  *   drive_sectors
129  *   stored_on_device
130  *   gpt_device_sectors
131  *
132  * On return the modified field may be set, if the GPT data has been modified
133  * and should be written to disk.
134  *
135  * Returns GPT_SUCCESS if successful, non-zero if error:
136  *   GPT_ERROR_INVALID_HEADERS, both partition table headers are invalid, enters
137  *                              recovery mode,
138  *   GPT_ERROR_INVALID_ENTRIES, both partition table entries are invalid, enters
139  *                              recovery mode,
140  *   GPT_ERROR_INVALID_SECTOR_SIZE, size of a sector is not supported,
141  *   GPT_ERROR_INVALID_SECTOR_NUMBER, number of sectors in drive is invalid (too
142  *                                    small) */
143 int GptInit(GptData *gpt);
144 
145 /**
146  * Return the nth instance of parition entry matching the partition type guid
147  * from the gpt table. Instance value starts from 0. If the entry is not found,
148  * it returns NULL.
149  */
150 GptEntry *GptFindNthEntry(GptData *gpt, const Guid *guid, unsigned int n);
151 
152 /**
153  * Allocate and read GPT data from the drive.  The sector_bytes and
154  * drive_sectors fields should be filled on input.  The primary and secondary
155  * header and entries are filled on output.
156  *
157  * Returns 0 if successful, 1 if error.
158  */
159 int AllocAndReadGptData(vb2ex_disk_handle_t disk_handle, GptData *gptdata);
160 
161 /**
162  * Write any changes for the GPT data back to the drive, then free the buffers.
163  */
164 int WriteAndFreeGptData(vb2ex_disk_handle_t disk_handle, GptData *gptdata);
165 
166 /**
167  * Return 1 if the entry is unused, 0 if it is used.
168  */
169 int IsUnusedEntry(const GptEntry *e);
170 
171 /**
172  * Return size(in lba) of a partition represented by given GPT entry.
173  */
174 uint64_t GptGetEntrySizeLba(const GptEntry *e);
175 
176 /**
177  * Return size(in bytes) of a partition represented by given GPT entry.
178  */
179 uint64_t GptGetEntrySizeBytes(const GptData *gpt, const GptEntry *e);
180 
181 /**
182  * Updates the kernel entry with the specified index, using the specified type
183  * of update (GPT_UPDATE_ENTRY_*).
184  *
185  * On return the modified field may be set, if the GPT data has been modified
186  * and should be written to disk.
187  *
188  * Returns GPT_SUCCESS if successful, else
189  *   GPT_ERROR_INVALID_UPDATE_TYPE, invalid 'update_type' is given.
190  */
191 int GptUpdateKernelWithEntry(GptData *gpt, GptEntry *e, uint32_t update_type);
192 
193 /**
194  * Updates the kernel entry identified by current_kernel field. If
195  * current_kernel is not set it returns an error.
196  *
197  * Returns GPT_SUCCESS if successful, else
198  *   GPT_ERROR_INVALID_UPDATE_TYPE, invalid 'update_type' is given.
199  */
200 int GptUpdateKernelEntry(GptData *gpt, uint32_t update_type);
201 
202 /* Getters and setters for partition attribute fields. */
203 
204 int GetEntryRequired(const GptEntry *e);
205 int GetEntryLegacyBoot(const GptEntry *e);
206 int GetEntrySuccessful(const GptEntry *e);
207 int GetEntryPriority(const GptEntry *e);
208 int GetEntryTries(const GptEntry *e);
209 int GetEntryErrorCounter(const GptEntry *e);
210 void SetEntryRequired(GptEntry *e, int required);
211 void SetEntryLegacyBoot(GptEntry *e, int legacy_boot);
212 void SetEntrySuccessful(GptEntry *e, int successful);
213 void SetEntryPriority(GptEntry *e, int priority);
214 void SetEntryTries(GptEntry *e, int tries);
215 void SetEntryErrorCounter(GptEntry *e, int error_counter);
216 
217 #ifdef __cplusplus
218 }
219 #endif  /* __cplusplus */
220 
221 #endif  /* VBOOT_REFERENCE_GPT_MISC_H_ */
222