blob: 4ec3ee4f775eaa364f3a1debe0af6452315e4101
1 | #if ENABLE_FEATURE_GPT_LABEL |
2 | /* |
3 | * Copyright (C) 2010 Kevin Cernekee <cernekee@gmail.com> |
4 | * |
5 | * Licensed under GPLv2, see file LICENSE in this source tree. |
6 | */ |
7 | |
8 | #define GPT_MAGIC 0x5452415020494645ULL |
9 | enum { |
10 | LEGACY_GPT_TYPE = 0xee, |
11 | GPT_MAX_PARTS = 256, |
12 | GPT_MAX_PART_ENTRY_LEN = 4096, |
13 | GUID_LEN = 16, |
14 | }; |
15 | |
16 | typedef struct { |
17 | uint64_t magic; |
18 | uint32_t revision; |
19 | uint32_t hdr_size; |
20 | uint32_t hdr_crc32; |
21 | uint32_t reserved; |
22 | uint64_t current_lba; |
23 | uint64_t backup_lba; |
24 | uint64_t first_usable_lba; |
25 | uint64_t last_usable_lba; |
26 | uint8_t disk_guid[GUID_LEN]; |
27 | uint64_t first_part_lba; |
28 | uint32_t n_parts; |
29 | uint32_t part_entry_len; |
30 | uint32_t part_array_crc32; |
31 | } gpt_header; |
32 | |
33 | typedef struct { |
34 | uint8_t type_guid[GUID_LEN]; |
35 | uint8_t part_guid[GUID_LEN]; |
36 | uint64_t lba_start; |
37 | uint64_t lba_end; |
38 | uint64_t flags; |
39 | uint16_t name[36]; |
40 | } gpt_partition; |
41 | |
42 | static gpt_header *gpt_hdr; |
43 | |
44 | static char *part_array; |
45 | static unsigned int n_parts; |
46 | static unsigned int part_array_len; |
47 | static unsigned int part_entry_len; |
48 | |
49 | static inline gpt_partition * |
50 | gpt_part(unsigned i) |
51 | { |
52 | if (i >= n_parts) { |
53 | return NULL; |
54 | } |
55 | return (gpt_partition *)&part_array[i * part_entry_len]; |
56 | } |
57 | |
58 | static uint32_t |
59 | gpt_crc32(void *buf, int len) |
60 | { |
61 | return ~crc32_block_endian0(0xffffffff, buf, len, global_crc32_table); |
62 | } |
63 | |
64 | static void |
65 | gpt_print_guid(uint8_t *buf) |
66 | { |
67 | printf( |
68 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
69 | buf[3], buf[2], buf[1], buf[0], |
70 | buf[5], buf[4], |
71 | buf[7], buf[6], |
72 | buf[8], buf[9], |
73 | buf[10], buf[11], buf[12], buf[13], buf[14], buf[15]); |
74 | } |
75 | |
76 | /* TODO: real unicode support */ |
77 | static void |
78 | gpt_print_wide(uint16_t *s, int max_len) |
79 | { |
80 | int i = 0; |
81 | |
82 | while (i < max_len) { |
83 | if (*s == 0) |
84 | return; |
85 | fputc(*s, stdout); |
86 | s++; |
87 | } |
88 | } |
89 | |
90 | static void |
91 | gpt_list_table(int xtra UNUSED_PARAM) |
92 | { |
93 | unsigned i; |
94 | char numstr6[6]; |
95 | |
96 | smart_ulltoa5(total_number_of_sectors * sector_size, numstr6, " KMGTPEZY")[0] = '\0'; |
97 | printf("Disk %s: %llu sectors, %s\n", disk_device, |
98 | (unsigned long long)total_number_of_sectors, |
99 | numstr6); |
100 | printf("Logical sector size: %u\n", sector_size); |
101 | printf("Disk identifier (GUID): "); |
102 | gpt_print_guid(gpt_hdr->disk_guid); |
103 | printf("\nPartition table holds up to %u entries\n", |
104 | (int)SWAP_LE32(gpt_hdr->n_parts)); |
105 | printf("First usable sector is %llu, last usable sector is %llu\n\n", |
106 | (unsigned long long)SWAP_LE64(gpt_hdr->first_usable_lba), |
107 | (unsigned long long)SWAP_LE64(gpt_hdr->last_usable_lba)); |
108 | |
109 | printf("Number Start (sector) End (sector) Size Code Name\n"); |
110 | for (i = 0; i < n_parts; i++) { |
111 | gpt_partition *p = gpt_part(i); |
112 | if (p->lba_start) { |
113 | smart_ulltoa5((1 + SWAP_LE64(p->lba_end) - SWAP_LE64(p->lba_start)) * sector_size, |
114 | numstr6, " KMGTPEZY")[0] = '\0'; |
115 | printf("%4u %15llu %15llu %11s %04x ", |
116 | i + 1, |
117 | (unsigned long long)SWAP_LE64(p->lba_start), |
118 | (unsigned long long)SWAP_LE64(p->lba_end), |
119 | numstr6, |
120 | 0x0700 /* FIXME */); |
121 | gpt_print_wide(p->name, 18); |
122 | printf("\n"); |
123 | } |
124 | } |
125 | } |
126 | |
127 | static int |
128 | check_gpt_label(void) |
129 | { |
130 | struct partition *first = pt_offset(MBRbuffer, 0); |
131 | struct pte pe; |
132 | uint32_t crc; |
133 | |
134 | /* LBA 0 contains the legacy MBR */ |
135 | |
136 | if (!valid_part_table_flag(MBRbuffer) |
137 | || first->sys_ind != LEGACY_GPT_TYPE |
138 | ) { |
139 | current_label_type = 0; |
140 | return 0; |
141 | } |
142 | |
143 | /* LBA 1 contains the GPT header */ |
144 | |
145 | read_pte(&pe, 1); |
146 | gpt_hdr = (void *)pe.sectorbuffer; |
147 | |
148 | if (gpt_hdr->magic != SWAP_LE64(GPT_MAGIC)) { |
149 | current_label_type = 0; |
150 | return 0; |
151 | } |
152 | |
153 | if (!global_crc32_table) { |
154 | global_crc32_table = crc32_filltable(NULL, 0); |
155 | } |
156 | |
157 | crc = SWAP_LE32(gpt_hdr->hdr_crc32); |
158 | gpt_hdr->hdr_crc32 = 0; |
159 | if (gpt_crc32(gpt_hdr, SWAP_LE32(gpt_hdr->hdr_size)) != crc) { |
160 | /* FIXME: read the backup table */ |
161 | puts("\nwarning: GPT header CRC is invalid\n"); |
162 | } |
163 | |
164 | n_parts = SWAP_LE32(gpt_hdr->n_parts); |
165 | part_entry_len = SWAP_LE32(gpt_hdr->part_entry_len); |
166 | if (n_parts > GPT_MAX_PARTS |
167 | || part_entry_len > GPT_MAX_PART_ENTRY_LEN |
168 | || SWAP_LE32(gpt_hdr->hdr_size) > sector_size |
169 | ) { |
170 | puts("\nwarning: unable to parse GPT disklabel\n"); |
171 | current_label_type = 0; |
172 | return 0; |
173 | } |
174 | |
175 | part_array_len = n_parts * part_entry_len; |
176 | part_array = xmalloc(part_array_len); |
177 | seek_sector(SWAP_LE64(gpt_hdr->first_part_lba)); |
178 | if (full_read(dev_fd, part_array, part_array_len) != (ssize_t) part_array_len) { |
179 | fdisk_fatal(unable_to_read); |
180 | } |
181 | |
182 | if (gpt_crc32(part_array, part_array_len) != gpt_hdr->part_array_crc32) { |
183 | /* FIXME: read the backup table */ |
184 | puts("\nwarning: GPT array CRC is invalid\n"); |
185 | } |
186 | |
187 | puts("Found valid GPT with protective MBR; using GPT\n"); |
188 | |
189 | current_label_type = LABEL_GPT; |
190 | return 1; |
191 | } |
192 | |
193 | #endif /* GPT_LABEL */ |
194 |