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
StrCopy(char * dest,const char * src,int dest_size)20 char* 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
ReadFile(const char * filename,uint64_t * sizeptr)27 uint8_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
ReadFileString(char * dest,int size,const char * filename)62 char* 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
ReadFileInt(const char * filename,unsigned * value)76 int 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
ReadFileBit(const char * filename,int bitmask)92 int 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
WriteFile(const char * filename,const void * data,uint64_t size)100 int 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