xref: /openbmc/u-boot/tools/mkenvimage.c (revision c6af2e7d)
1 /*
2  * (C) Copyright 2011 Free Electrons
3  * David Wagner <david.wagner@free-electrons.com>
4  *
5  * Inspired from envcrc.c:
6  * (C) Copyright 2001
7  * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
8  *
9  * See file CREDITS for list of people who contributed to this
10  * project.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of
15  * the License, or (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25  * MA 02111-1307 USA
26  */
27 
28 /* We want the GNU version of basename() */
29 #define _GNU_SOURCE
30 
31 #include <errno.h>
32 #include <fcntl.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <stdint.h>
36 #include <string.h>
37 #include <unistd.h>
38 #include <libgen.h>
39 #include <sys/types.h>
40 #include <sys/stat.h>
41 #include <sys/mman.h>
42 
43 #include "compiler.h"
44 #include <u-boot/crc.h>
45 #include <version.h>
46 
47 #define CRC_SIZE sizeof(uint32_t)
48 
49 static void usage(const char *exec_name)
50 {
51 	fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
52 	       "\n"
53 	       "This tool takes a key=value input file (same as would a `printenv' show) and generates the corresponding environment image, ready to be flashed.\n"
54 	       "\n"
55 	       "\tThe input file is in format:\n"
56 	       "\t\tkey1=value1\n"
57 	       "\t\tkey2=value2\n"
58 	       "\t\t...\n"
59 	       "\t-r : the environment has multiple copies in flash\n"
60 	       "\t-b : the target is big endian (default is little endian)\n"
61 	       "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
62 	       "\t-V : print version information and exit\n"
63 	       "\n"
64 	       "If the input file is \"-\", data is read from standard input\n",
65 	       exec_name);
66 }
67 
68 long int xstrtol(const char *s)
69 {
70 	long int tmp;
71 
72 	errno = 0;
73 	tmp = strtol(s, NULL, 0);
74 	if (!errno)
75 		return tmp;
76 
77 	if (errno == ERANGE)
78 		fprintf(stderr, "Bad integer format: %s\n",  s);
79 	else
80 		fprintf(stderr, "Error while parsing %s: %s\n", s,
81 				strerror(errno));
82 
83 	exit(EXIT_FAILURE);
84 }
85 
86 int main(int argc, char **argv)
87 {
88 	uint32_t crc, targetendian_crc;
89 	const char *txt_filename = NULL, *bin_filename = NULL;
90 	int txt_fd, bin_fd;
91 	unsigned char *dataptr, *envptr;
92 	unsigned char *filebuf = NULL;
93 	unsigned int filesize = 0, envsize = 0, datasize = 0;
94 	int bigendian = 0;
95 	int redundant = 0;
96 	unsigned char padbyte = 0xff;
97 
98 	int option;
99 	int ret = EXIT_SUCCESS;
100 
101 	struct stat txt_file_stat;
102 
103 	int fp, ep;
104 	const char *prg;
105 
106 	prg = basename(argv[0]);
107 
108 	/* Turn off getopt()'s internal error message */
109 	opterr = 0;
110 
111 	/* Parse the cmdline */
112 	while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
113 		switch (option) {
114 		case 's':
115 			datasize = xstrtol(optarg);
116 			break;
117 		case 'o':
118 			bin_filename = strdup(optarg);
119 			if (!bin_filename) {
120 				fprintf(stderr, "Can't strdup() the output filename\n");
121 				return EXIT_FAILURE;
122 			}
123 			break;
124 		case 'r':
125 			redundant = 1;
126 			break;
127 		case 'b':
128 			bigendian = 1;
129 			break;
130 		case 'p':
131 			padbyte = xstrtol(optarg);
132 			break;
133 		case 'h':
134 			usage(prg);
135 			return EXIT_SUCCESS;
136 		case 'V':
137 			printf("%s version %s\n", prg, PLAIN_VERSION);
138 			return EXIT_SUCCESS;
139 		case ':':
140 			fprintf(stderr, "Missing argument for option -%c\n",
141 				optopt);
142 			usage(prg);
143 			return EXIT_FAILURE;
144 		default:
145 			fprintf(stderr, "Wrong option -%c\n", optopt);
146 			usage(prg);
147 			return EXIT_FAILURE;
148 		}
149 	}
150 
151 	/* Check datasize and allocate the data */
152 	if (datasize == 0) {
153 		fprintf(stderr, "Please specify the size of the environment partition.\n");
154 		usage(prg);
155 		return EXIT_FAILURE;
156 	}
157 
158 	dataptr = malloc(datasize * sizeof(*dataptr));
159 	if (!dataptr) {
160 		fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
161 				datasize);
162 		return EXIT_FAILURE;
163 	}
164 
165 	/*
166 	 * envptr points to the beginning of the actual environment (after the
167 	 * crc and possible `redundant' byte
168 	 */
169 	envsize = datasize - (CRC_SIZE + redundant);
170 	envptr = dataptr + CRC_SIZE + redundant;
171 
172 	/* Pad the environment with the padding byte */
173 	memset(envptr, padbyte, envsize);
174 
175 	/* Open the input file ... */
176 	if (optind >= argc || strcmp(argv[optind], "-") == 0) {
177 		int readbytes = 0;
178 		int readlen = sizeof(*envptr) * 4096;
179 		txt_fd = STDIN_FILENO;
180 
181 		do {
182 			filebuf = realloc(filebuf, readlen);
183 			if (!filebuf) {
184 				fprintf(stderr, "Can't realloc memory for the input file buffer\n");
185 				return EXIT_FAILURE;
186 			}
187 			readbytes = read(txt_fd, filebuf + filesize, readlen);
188 			if (errno) {
189 				fprintf(stderr, "Error while reading stdin: %s\n",
190 						strerror(errno));
191 				return EXIT_FAILURE;
192 			}
193 			filesize += readbytes;
194 		} while (readbytes == readlen);
195 
196 	} else {
197 		txt_filename = argv[optind];
198 		txt_fd = open(txt_filename, O_RDONLY);
199 		if (txt_fd == -1) {
200 			fprintf(stderr, "Can't open \"%s\": %s\n",
201 					txt_filename, strerror(errno));
202 			return EXIT_FAILURE;
203 		}
204 		/* ... and check it */
205 		ret = fstat(txt_fd, &txt_file_stat);
206 		if (ret == -1) {
207 			fprintf(stderr, "Can't stat() on \"%s\": %s\n",
208 					txt_filename, strerror(errno));
209 			return EXIT_FAILURE;
210 		}
211 
212 		filesize = txt_file_stat.st_size;
213 
214 		filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
215 			       MAP_PRIVATE, txt_fd, 0);
216 		if (filebuf == MAP_FAILED) {
217 			fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
218 					sizeof(*envptr) * filesize,
219 					strerror(errno));
220 			fprintf(stderr, "Falling back to read()\n");
221 
222 			filebuf = malloc(sizeof(*envptr) * filesize);
223 			ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
224 			if (ret != sizeof(*envptr) * filesize) {
225 				fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
226 					sizeof(*envptr) * filesize,
227 					strerror(errno));
228 
229 				return EXIT_FAILURE;
230 			}
231 		}
232 		ret = close(txt_fd);
233 	}
234 	/* The +1 is for the additionnal ending \0. See below. */
235 	if (filesize + 1 > envsize) {
236 		fprintf(stderr, "The input file is larger than the environment partition size\n");
237 		return EXIT_FAILURE;
238 	}
239 
240 	/* Replace newlines separating variables with \0 */
241 	for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
242 		if (filebuf[fp] == '\n') {
243 			if (ep == 0) {
244 				/*
245 				 * Newlines at the beginning of the file ?
246 				 * Ignore them.
247 				 */
248 				continue;
249 			} else if (filebuf[fp-1] == '\\') {
250 				/*
251 				 * Embedded newline in a variable.
252 				 *
253 				 * The backslash was added to the envptr; rewind
254 				 * and replace it with a newline
255 				 */
256 				ep--;
257 				envptr[ep++] = '\n';
258 			} else {
259 				/* End of a variable */
260 				envptr[ep++] = '\0';
261 			}
262 		} else {
263 			envptr[ep++] = filebuf[fp];
264 		}
265 	}
266 	/*
267 	 * Make sure there is a final '\0'
268 	 * And do it again on the next byte to mark the end of the environment.
269 	 */
270 	if (envptr[ep-1] != '\0') {
271 		envptr[ep++] = '\0';
272 		/*
273 		 * The text file doesn't have an ending newline.  We need to
274 		 * check the env size again to make sure we have room for two \0
275 		 */
276 		if (ep >= envsize) {
277 			fprintf(stderr, "The environment file is too large for the target environment storage\n");
278 			return EXIT_FAILURE;
279 		}
280 		envptr[ep] = '\0';
281 	} else {
282 		envptr[ep] = '\0';
283 	}
284 
285 	/* Computes the CRC and put it at the beginning of the data */
286 	crc = crc32(0, envptr, envsize);
287 	targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
288 
289 	memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
290 	if (redundant)
291 		dataptr[sizeof(targetendian_crc)] = 1;
292 
293 	if (!bin_filename || strcmp(bin_filename, "-") == 0) {
294 		bin_fd = STDOUT_FILENO;
295 	} else {
296 		bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
297 					     S_IWGRP);
298 		if (bin_fd == -1) {
299 			fprintf(stderr, "Can't open output file \"%s\": %s\n",
300 					bin_filename, strerror(errno));
301 			return EXIT_FAILURE;
302 		}
303 	}
304 
305 	if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
306 			sizeof(*dataptr) * datasize) {
307 		fprintf(stderr, "write() failed: %s\n", strerror(errno));
308 		return EXIT_FAILURE;
309 	}
310 
311 	ret = close(bin_fd);
312 
313 	return ret;
314 }
315