1 /* Copyright 2012 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 #include <errno.h>
7 #include <fcntl.h>
8 #include <string.h>
9 #include <unistd.h>
10
11 #include "cgpt.h"
12 #include "cgptlib_internal.h"
13 #include "cgpt_params.h"
14 #include "vboot_host.h"
15
CgptGetBootPartitionNumber(CgptBootParams * params)16 int CgptGetBootPartitionNumber(CgptBootParams *params) {
17 struct drive drive;
18 int gpt_retval= 0;
19 int retval;
20
21 if (params == NULL)
22 return CGPT_FAILED;
23
24 if (CGPT_OK != DriveOpen(params->drive_name, &drive, O_RDONLY,
25 params->drive_size))
26 return CGPT_FAILED;
27
28 if (GPT_SUCCESS != (gpt_retval = GptValidityCheck(&drive.gpt))) {
29 Error("GptValidityCheck() returned %d: %s\n",
30 gpt_retval, GptError(gpt_retval));
31 retval = CGPT_FAILED;
32 goto done;
33 }
34
35 if (CGPT_OK != ReadPMBR(&drive)) {
36 Error("Unable to read PMBR\n");
37 retval = CGPT_FAILED;
38 goto done;
39 }
40
41 char buf[GUID_STRLEN];
42 GuidToStr(&drive.pmbr.boot_guid, buf, sizeof(buf));
43
44 int numEntries = GetNumberOfEntries(&drive);
45 int i;
46 for (i = 0; i < numEntries; i++) {
47 GptEntry *entry = GetEntry(&drive.gpt, ANY_VALID, i);
48
49 if (GuidEqual(&entry->unique, &drive.pmbr.boot_guid)) {
50 params->partition = i + 1;
51 retval = CGPT_OK;
52 goto done;
53 }
54 }
55
56 Error("Didn't find any boot partition\n");
57 params->partition = 0;
58 retval = CGPT_FAILED;
59
60 done:
61 (void) DriveClose(&drive, 1);
62 return retval;
63 }
64
65
CgptBoot(CgptBootParams * params)66 int CgptBoot(CgptBootParams *params) {
67 struct drive drive;
68 int retval = 1;
69 int gpt_retval= 0;
70 int mode = O_RDONLY;
71
72 if (params == NULL)
73 return CGPT_FAILED;
74
75 if (params->create_pmbr || params->partition || params->bootfile)
76 mode = O_RDWR;
77
78 if (CGPT_OK != DriveOpen(params->drive_name, &drive, mode,
79 params->drive_size)) {
80 return CGPT_FAILED;
81 }
82
83 if (CGPT_OK != ReadPMBR(&drive)) {
84 Error("Unable to read PMBR\n");
85 goto done;
86 }
87
88 if (params->create_pmbr) {
89 drive.pmbr.magic[0] = 0x1d;
90 drive.pmbr.magic[1] = 0x9a;
91 drive.pmbr.sig[0] = 0x55;
92 drive.pmbr.sig[1] = 0xaa;
93 memset(&drive.pmbr.part, 0, sizeof(drive.pmbr.part));
94 drive.pmbr.part[0].f_head = 0x00;
95 drive.pmbr.part[0].f_sect = 0x02;
96 drive.pmbr.part[0].f_cyl = 0x00;
97 drive.pmbr.part[0].type = 0xee;
98 drive.pmbr.part[0].l_head = 0xff;
99 drive.pmbr.part[0].l_sect = 0xff;
100 drive.pmbr.part[0].l_cyl = 0xff;
101 drive.pmbr.part[0].f_lba = htole32(1);
102 uint32_t max = 0xffffffff;
103 if (drive.gpt.streaming_drive_sectors < 0xffffffff)
104 max = drive.gpt.streaming_drive_sectors - 1;
105 drive.pmbr.part[0].num_sect = htole32(max);
106 }
107
108 if (params->partition) {
109 if (GPT_SUCCESS != (gpt_retval = GptValidityCheck(&drive.gpt))) {
110 Error("GptValidityCheck() returned %d: %s\n",
111 gpt_retval, GptError(gpt_retval));
112 goto done;
113 }
114
115 if (params->partition > GetNumberOfEntries(&drive)) {
116 Error("invalid partition number: %d\n", params->partition);
117 goto done;
118 }
119
120 uint32_t index = params->partition - 1;
121 GptEntry *entry = GetEntry(&drive.gpt, ANY_VALID, index);
122 memcpy(&drive.pmbr.boot_guid, &entry->unique, sizeof(Guid));
123 }
124
125 if (params->bootfile) {
126 int fd = open(params->bootfile, O_RDONLY);
127 if (fd < 0) {
128 Error("Can't read %s: %s\n", params->bootfile, strerror(errno));
129 goto done;
130 }
131
132 int n = read(fd, drive.pmbr.bootcode, sizeof(drive.pmbr.bootcode));
133 if (n < 1) {
134 Error("problem reading %s: %s\n", params->bootfile, strerror(errno));
135 close(fd);
136 goto done;
137 }
138
139 close(fd);
140 }
141
142 char buf[GUID_STRLEN];
143 GuidToStr(&drive.pmbr.boot_guid, buf, sizeof(buf));
144 printf("%s\n", buf);
145
146 // Write it all out, if needed.
147 if (mode == O_RDONLY || CGPT_OK == WritePMBR(&drive))
148 retval = 0;
149
150 done:
151 (void) DriveClose(&drive, 1);
152 return retval;
153 }
154