1/* Copyright (c) 2011 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 verified boot.
6 */
7
8/* TODO: change all 'return 0', 'return 1' into meaningful return codes */
9
10#include <stdio.h>
11#include <stdlib.h>
12#include <string.h>
13#include <unistd.h>
14
15#include "cryptolib.h"
16#include "host_common.h"
17#include "vboot_common.h"
18
19
20char* StrCopy(char* dest, const char* src, int dest_size) {
21  strncpy(dest, src, dest_size);
22  dest[dest_size - 1] = '\0';
23  return dest;
24}
25
26
27uint8_t* ReadFile(const char* filename, uint64_t* sizeptr) {
28  FILE* f;
29  uint8_t* buf;
30  uint64_t size;
31
32  f = fopen(filename, "rb");
33  if (!f) {
34    VBDEBUG(("Unable to open file %s\n", filename));
35    return NULL;
36  }
37
38  fseek(f, 0, SEEK_END);
39  size = ftell(f);
40  rewind(f);
41
42  buf = malloc(size);
43  if (!buf) {
44    fclose(f);
45    return NULL;
46  }
47
48  if(1 != fread(buf, size, 1, f)) {
49    VBDEBUG(("Unable to read from file %s\n", filename));
50    fclose(f);
51    free(buf);
52    return NULL;
53  }
54
55  fclose(f);
56  if (sizeptr)
57    *sizeptr = size;
58  return buf;
59}
60
61
62char* ReadFileString(char* dest, int size, const char* filename) {
63  char* got;
64  FILE* f;
65
66  f = fopen(filename, "rt");
67  if (!f)
68    return NULL;
69
70  got = fgets(dest, size, f);
71  fclose(f);
72  return got;
73}
74
75
76int ReadFileInt(const char* filename, unsigned* value) {
77  char buf[64];
78  char* e = NULL;
79
80  if (!ReadFileString(buf, sizeof(buf), filename))
81    return -1;
82
83  /* Convert to integer.  Allow characters after the int ("123 blah"). */
84  *value = (unsigned)strtoul(buf, &e, 0);
85  if (e == buf)
86    return -1;  /* No characters consumed, so conversion failed */
87
88  return 0;
89}
90
91
92int ReadFileBit(const char* filename, int bitmask) {
93  unsigned value;
94  if (ReadFileInt(filename, &value) < 0)
95    return -1;
96  else return (value & bitmask ? 1 : 0);
97}
98
99
100int WriteFile(const char* filename, const void *data, uint64_t size) {
101  FILE *f = fopen(filename, "wb");
102  if (!f) {
103    VBDEBUG(("Unable to open file %s\n", filename));
104    return 1;
105  }
106
107  if (1 != fwrite(data, size, 1, f)) {
108    VBDEBUG(("Unable to write to file %s\n", filename));
109    fclose(f);
110    unlink(filename);  /* Delete any partial file */
111    return 1;
112  }
113
114  fclose(f);
115  return 0;
116}
117