xref: /aosp_15_r20/external/vboot_reference/futility/cmd_load_fmap.c (revision 8617a60d3594060b7ecbd21bc622a7c14f3cf2bc)
1 /* Copyright 2014 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 <getopt.h>
9 #include <inttypes.h>
10 #include <limits.h>
11 #include <stddef.h>
12 #include <stdint.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/stat.h>
17 #include <sys/types.h>
18 #include <unistd.h>
19 
20 #include "fmap.h"
21 #include "futility.h"
22 
23 static const char usage[] = "\n"
24 	"Usage:  " MYNAME " %s [OPTIONS] FILE AREA:file [AREA:file ...]\n"
25 	"\n"
26 	"Replace the contents of specific FMAP areas. This is the complement\n"
27 	"of " MYNAME " dump_fmap -x FILE AREA [AREA ...]\n"
28 	"\n"
29 	"Options:\n"
30 	"  -o OUTFILE     Write the result to this file, instead of modifying\n"
31 	"                   the input file. This is safer, since there are no\n"
32 	"                   safeguards against doing something stupid.\n"
33 	"\n"
34 	"Example:\n"
35 	"\n"
36 	"  This will clear the RO_VPD area, and scramble VBLOCK_B:\n"
37 	"\n"
38 	"  " MYNAME " %s image.bin RO_VPD:/dev/zero VBLOCK_B:/dev/urandom\n"
39 	"\n";
40 
print_help(int argc,char * argv[])41 static void print_help(int argc, char *argv[])
42 {
43 	printf(usage, argv[0], argv[0]);
44 }
45 
46 enum {
47 	OPT_HELP = 1000,
48 };
49 static const struct option long_opts[] = {
50 	/* name    hasarg *flag  val */
51 	{"help",        0, NULL, OPT_HELP},
52 	{NULL,          0, NULL, 0},
53 };
54 static const char *short_opts = ":o:";
55 
56 
copy_to_area(const char * file,uint8_t * buf,const uint32_t len,const char * area)57 static int copy_to_area(const char *file, uint8_t *buf,
58 			const uint32_t len, const char *area)
59 {
60 	int retval = 0;
61 
62 	FILE *fp = fopen(file, "r");
63 	if (!fp) {
64 		ERROR("area %s: can't open %s for reading: %s\n",
65 			area, file, strerror(errno));
66 		return 1;
67 	}
68 
69 	size_t n = fread(buf, 1, len, fp);
70 	if (!n) {
71 		if (feof(fp))
72 			ERROR("area %s: unexpected EOF on %s\n", area, file);
73 		if (ferror(fp))
74 			ERROR("area %s: can't read from %s: %s\n",
75 				area, file, strerror(errno));
76 		retval = 1;
77 	} else if (n < len) {
78 		WARN("area %s: %s size (%zu) smaller than area size %u; "
79 		     "erasing remaining data to 0xff\n",
80 		     area, file, n, len);
81 		memset(buf + n, 0xff, len - n);
82 	}
83 
84 	if (fclose(fp)) {
85 		ERROR("area %s: error closing %s: %s\n",
86 			area, file, strerror(errno));
87 		retval = 1;
88 	}
89 
90 	return retval;
91 }
92 
93 
do_load_fmap(int argc,char * argv[])94 static int do_load_fmap(int argc, char *argv[])
95 {
96 	char *outfile = NULL;
97 	int errorcnt = 0;
98 	int i;
99 
100 	opterr = 0;		/* quiet, you */
101 	while ((i = getopt_long(argc, argv, short_opts, long_opts, 0)) != -1) {
102 		switch (i) {
103 		case 'o':
104 			outfile = optarg;
105 			break;
106 		case OPT_HELP:
107 			print_help(argc, argv);
108 			return !!errorcnt;
109 		case '?':
110 			if (optopt)
111 				ERROR("Unrecognized option: -%c\n",
112 					optopt);
113 			else
114 				ERROR("Unrecognized option\n");
115 			errorcnt++;
116 			break;
117 		case ':':
118 			ERROR("Missing argument to -%c\n", optopt);
119 			errorcnt++;
120 			break;
121 		default:
122 			FATAL("Unrecognized getopt output: %d\n", i);
123 		}
124 	}
125 
126 	if (errorcnt) {
127 		print_help(argc, argv);
128 		return 1;
129 	}
130 
131 	if (argc - optind < 2) {
132 		ERROR("You must specify an input file"
133 			" and at least one AREA:file argument\n");
134 		print_help(argc, argv);
135 		return 1;
136 	}
137 
138 	const char *infile = argv[optind++];
139 
140 	/* okay, let's do it ... */
141 	if (!outfile)
142 		outfile = (char *)infile;
143 	else
144 		if (futil_copy_file(infile, outfile) < 0)
145 			exit(1);
146 
147 	int fd;
148 	uint8_t *buf;
149 	uint32_t len;
150 	errorcnt |= futil_open_and_map_file(outfile, &fd, FILE_RW, &buf, &len);
151 	if (errorcnt)
152 		goto done;
153 
154 	FmapHeader *fmap = fmap_find(buf, len);
155 	if (!fmap) {
156 		ERROR("Can't find an FMAP in %s\n", infile);
157 		errorcnt++;
158 		goto done;
159 	}
160 
161 	for (i = optind; i < argc; i++) {
162 		char *a = argv[i];
163 		char *f = strchr(a, ':');
164 
165 		if (!f || a == f || *(f+1) == '\0') {
166 			ERROR("argument \"%s\" is bogus\n", a);
167 			errorcnt++;
168 			break;
169 		}
170 		*f++ = '\0';
171 
172 		FmapAreaHeader *ah;
173 		uint8_t *area_buf = fmap_find_by_name(buf, len, fmap, a, &ah);
174 		if (!area_buf) {
175 			ERROR("Can't find area \"%s\" in FMAP\n", a);
176 			errorcnt++;
177 			break;
178 		}
179 
180 		if (copy_to_area(f, area_buf, ah->area_size, a)) {
181 			errorcnt++;
182 			break;
183 		}
184 	}
185 
186 done:
187 	errorcnt |= futil_unmap_and_close_file(fd, FILE_RW, buf, len);
188 	return !!errorcnt;
189 }
190 
191 DECLARE_FUTIL_COMMAND(load_fmap, do_load_fmap, VBOOT_VERSION_ALL,
192 		      "Replace the contents of specified FMAP areas");
193