1 /* Copyright (c) 2013 The Chromium OS Authors. All rights reserved. 2 * Use of this source code is governed by a BSD-style license that can be 3 * found in the LICENSE file. 4 * 5 * Defines UEFI related structure. See more details in the UEFI spec. 6 * 7 * To download UEFI standard, please visit UEFI homepage: 8 * http://www.uefi.org/ 9 */ 10 #ifndef VBOOT_REFERENCE_CGPTLIB_GPT_H_ 11 #define VBOOT_REFERENCE_CGPTLIB_GPT_H_ 12 #include <stdint.h> 13 14 /* From the specification */ 15 #define GPT_HEADER_SIGNATURE_SIZE 8 16 #define GPT_HEADER_REVISION 0x00010000 17 #define GPT_HEADER_SIGNATURE "EFI PART" 18 19 /* From https://chromium-review.googlesource.com/31264 */ 20 #define GPT_HEADER_SIGNATURE2 "CHROMEOS" 21 22 /* 23 * The first 3 numbers should be stored in network-endian format according to 24 * the GUID RFC. The UEFI spec appendix A claims they should be stored in 25 * little-endian format. But they need to be _displayed_ in network-endian 26 * format, which is also how they're documented in the specs. 27 * 28 * Since what we have here are little-endian constants, they're byte-swapped 29 * from the normal display order. 30 */ 31 #define GPT_ENT_TYPE_UNUSED \ 32 {{{0x00000000,0x0000,0x0000,0x00,0x00,{0x00,0x00,0x00,0x00,0x00,0x00}}}} 33 #define GPT_ENT_TYPE_EFI \ 34 {{{0xc12a7328,0xf81f,0x11d2,0xba,0x4b,{0x00,0xa0,0xc9,0x3e,0xc9,0x3b}}}} 35 #define GPT_ENT_TYPE_CHROMEOS_FIRMWARE \ 36 {{{0xcab6e88e,0xabf3,0x4102,0xa0,0x7a,{0xd4,0xbb,0x9b,0xe3,0xc1,0xd3}}}} 37 #define GPT_ENT_TYPE_CHROMEOS_KERNEL \ 38 {{{0xfe3a2a5d,0x4f32,0x41a7,0xb7,0x25,{0xac,0xcc,0x32,0x85,0xa3,0x09}}}} 39 #define GPT_ENT_TYPE_CHROMEOS_ROOTFS \ 40 {{{0x3cb8e202,0x3b7e,0x47dd,0x8a,0x3c,{0x7f,0xf2,0xa1,0x3c,0xfc,0xec}}}} 41 #define GPT_ENT_TYPE_CHROMEOS_RESERVED \ 42 {{{0x2e0a753d,0x9e48,0x43b0,0x83,0x37,{0xb1,0x51,0x92,0xcb,0x1b,0x5e}}}} 43 #define GPT_ENT_TYPE_LINUX_DATA \ 44 {{{0xebd0a0a2,0xb9e5,0x4433,0x87,0xc0,{0x68,0xb6,0xb7,0x26,0x99,0xc7}}}} 45 #define GPT_ENT_TYPE_LINUX_FS \ 46 {{{0x0fc63daf,0x8483,0x4772,0x8e,0x79,{0x3d,0x69,0xd8,0x47,0x7d,0xe4}}}} 47 48 #define UUID_NODE_LEN 6 49 #define GUID_SIZE 16 50 51 /* GUID definition. Defined in appendix A of UEFI standard. */ 52 typedef struct { 53 union { 54 struct { 55 uint32_t time_low; 56 uint16_t time_mid; 57 uint16_t time_high_and_version; 58 uint8_t clock_seq_high_and_reserved; 59 uint8_t clock_seq_low; 60 uint8_t node[UUID_NODE_LEN]; 61 } Uuid; 62 uint8_t raw[GUID_SIZE]; 63 } u; 64 } __attribute__((packed)) Guid; 65 66 #define GUID_EXPECTED_SIZE GUID_SIZE 67 68 /* 69 * GPT header defines how many partitions exist on a drive and sectors managed. 70 * For every drive device, there are 2 headers, primary and secondary. Most of 71 * the fields are duplicates except my_lba and entries_lba. 72 * 73 * You may find more details in chapter 5 of the UEFI standard. 74 */ 75 typedef struct { 76 char signature[GPT_HEADER_SIGNATURE_SIZE]; 77 uint32_t revision; 78 uint32_t size; 79 uint32_t header_crc32; 80 uint32_t reserved_zero; 81 uint64_t my_lba; 82 uint64_t alternate_lba; 83 uint64_t first_usable_lba; 84 uint64_t last_usable_lba; 85 Guid disk_uuid; 86 uint64_t entries_lba; 87 uint32_t number_of_entries; 88 uint32_t size_of_entry; 89 uint32_t entries_crc32; 90 /* Remainder of sector is reserved and should be 0 */ 91 } __attribute__((packed)) GptHeader; 92 93 #define GPTHEADER_EXPECTED_SIZE 92 94 95 /* 96 * GPT partition entry defines the starting and ending LBAs of a partition. It 97 * also contains the unique GUID, type, and attribute bits. 98 * 99 * You may find more details in chapter 5 of the UEFI standard. 100 */ 101 typedef struct { 102 Guid type; 103 Guid unique; 104 uint64_t starting_lba; 105 uint64_t ending_lba; 106 union { 107 struct { 108 uint16_t reserved[3]; 109 uint16_t gpt_att; 110 } __attribute__((packed)) fields; 111 uint64_t whole; 112 } attrs; 113 uint16_t name[36]; /* UTF-16 encoded partition name */ 114 /* Remainder of entry is reserved and should be 0 */ 115 } __attribute__((packed)) GptEntry; 116 117 #define GPTENTRY_EXPECTED_SIZE 128 118 119 #endif /* VBOOT_REFERENCE_CGPTLIB_GPT_H_ */ 120