1/* Copyright (c) 2014 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 * Host functions for keyblocks
6 */
7
8#include "2sysincludes.h"
9#include "2common.h"
10#include "2rsa.h"
11#include "host_common.h"
12#include "host_fw_preamble2.h"
13#include "host_key2.h"
14#include "host_keyblock2.h"
15#include "host_misc.h"
16#include "host_signature2.h"
17#include "vb2_common.h"
18
19int vb2_fw_preamble_create(struct vb2_fw_preamble **fp_ptr,
20			   const struct vb2_private_key *signing_key,
21			   const struct vb2_signature **hash_list,
22			   uint32_t hash_count,
23			   uint32_t fw_version,
24			   uint32_t flags,
25			   const char *desc)
26{
27	struct vb2_fw_preamble fp = {
28		.c.magic = VB2_MAGIC_FW_PREAMBLE,
29		.c.struct_version_major = VB2_FW_PREAMBLE_VERSION_MAJOR,
30		.c.struct_version_minor = VB2_FW_PREAMBLE_VERSION_MAJOR,
31		.c.fixed_size = sizeof(fp),
32		.c.desc_size = vb2_desc_size(desc),
33		.flags = flags,
34		.fw_version = fw_version,
35		.hash_count = hash_count,
36	};
37
38	uint32_t hash_next;
39	uint32_t sig_size;
40	uint8_t *buf;
41	int i;
42
43	*fp_ptr = NULL;
44
45	/* Determine component sizes */
46	hash_next = fp.hash_offset = fp.c.fixed_size + fp.c.desc_size;
47
48	for (i = 0; i < hash_count; i++)
49		hash_next += hash_list[i]->c.total_size;
50
51	fp.sig_offset = hash_next;
52
53	if (vb2_sig_size_for_key(&sig_size, signing_key, NULL))
54		return VB2_FW_PREAMBLE_CREATE_SIG_SIZE;
55
56	fp.c.total_size = fp.sig_offset + sig_size;
57
58	/* Allocate buffer and copy components */
59	buf = calloc(fp.c.total_size, 1);
60	if (!buf)
61		return VB2_FW_PREAMBLE_CREATE_ALLOC;
62
63	memcpy(buf, &fp, sizeof(fp));
64	if (fp.c.desc_size)
65		strcpy((char *)buf + fp.c.fixed_size, desc);
66
67	hash_next = fp.hash_offset;
68	for (i = 0; i < hash_count; i++) {
69		memcpy(buf + hash_next, hash_list[i],
70		       hash_list[i]->c.total_size);
71		hash_next += hash_list[i]->c.total_size;
72	}
73
74	/* Sign the preamble */
75	if (vb2_sign_object(buf, fp.sig_offset, signing_key, NULL)) {
76		free(buf);
77		return VB2_FW_PREAMBLE_CREATE_SIGN;
78	}
79
80	*fp_ptr = (struct vb2_fw_preamble *)buf;
81	return VB2_SUCCESS;
82}
83