cgpt_boot.c revision a05814398202c4147a5e3f28474830ec0a9a0a90 
1// Copyright (c) 2012 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#include "cgpt.h"
6
7#include <errno.h>
8#include <fcntl.h>
9#include <string.h>
10
11#include "cgptlib_internal.h"
12#include "endian.h"
13#include "cgpt_params.h"
14
15int cgpt_boot(CgptBootParams *params) {
16  struct drive drive;
17  int retval = 1;
18  int gpt_retval= 0;
19
20  if (params == NULL)
21    return CGPT_FAILED;
22
23  if (CGPT_OK != DriveOpen(params->driveName, &drive))
24    return CGPT_FAILED;
25
26  if (CGPT_OK != ReadPMBR(&drive)) {
27    Error("Unable to read PMBR\n");
28    goto done;
29  }
30
31  if (params->create_pmbr) {
32    drive.pmbr.magic[0] = 0x1d;
33    drive.pmbr.magic[1] = 0x9a;
34    drive.pmbr.sig[0] = 0x55;
35    drive.pmbr.sig[1] = 0xaa;
36    memset(&drive.pmbr.part, 0, sizeof(drive.pmbr.part));
37    drive.pmbr.part[0].f_head = 0x00;
38    drive.pmbr.part[0].f_sect = 0x02;
39    drive.pmbr.part[0].f_cyl = 0x00;
40    drive.pmbr.part[0].type = 0xee;
41    drive.pmbr.part[0].l_head = 0xff;
42    drive.pmbr.part[0].l_sect = 0xff;
43    drive.pmbr.part[0].l_cyl = 0xff;
44    drive.pmbr.part[0].f_lba = htole32(1);
45    uint32_t max = 0xffffffff;
46    if (drive.gpt.drive_sectors < 0xffffffff)
47      max = drive.gpt.drive_sectors - 1;
48    drive.pmbr.part[0].num_sect = htole32(max);
49  }
50
51  if (params->partition) {
52    if (GPT_SUCCESS != (gpt_retval = GptSanityCheck(&drive.gpt))) {
53      Error("GptSanityCheck() returned %d: %s\n",
54            gpt_retval, GptError(gpt_retval));
55      goto done;
56    }
57
58    if (params->partition > GetNumberOfEntries(&drive.gpt)) {
59      Error("invalid partition number: %d\n", params->partition);
60      goto done;
61    }
62
63    uint32_t index = params->partition - 1;
64    GptEntry *entry = GetEntry(&drive.gpt, ANY_VALID, index);
65    memcpy(&drive.pmbr.boot_guid, &entry->unique, sizeof(Guid));
66  }
67
68  if (params->bootfile) {
69    int fd = open(params->bootfile, O_RDONLY);
70    if (fd < 0) {
71      Error("Can't read %s: %s\n", params->bootfile, strerror(errno));
72      goto done;
73    }
74
75    int n = read(fd, drive.pmbr.bootcode, sizeof(drive.pmbr.bootcode));
76    if (n < 1) {
77      Error("problem reading %s: %s\n", params->bootfile, strerror(errno));
78      close(fd);
79      goto done;
80    }
81
82    close(fd);
83  }
84
85  char buf[GUID_STRLEN];
86  GuidToStr(&drive.pmbr.boot_guid, buf, sizeof(buf));
87  printf("%s\n", buf);
88
89  // Write it all out
90  if (CGPT_OK == WritePMBR(&drive))
91    retval = 0;
92
93done:
94  (void) DriveClose(&drive, 1);
95  return retval;
96}
97