xref: /openbmc/u-boot/tools/mkenvimage.c (revision 1e52fea3)
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 <sys/types.h>
39 #include <sys/stat.h>
40 #include <sys/mman.h>
41 
42 #include "compiler.h"
43 #include <u-boot/crc.h>
44 #include <version.h>
45 
46 #define CRC_SIZE sizeof(uint32_t)
47 
48 static void usage(const char *exec_name)
49 {
50 	fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
51 	       "\n"
52 	       "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"
53 	       "\n"
54 	       "\tThe input file is in format:\n"
55 	       "\t\tkey1=value1\n"
56 	       "\t\tkey2=value2\n"
57 	       "\t\t...\n"
58 	       "\t-r : the environment has multiple copies in flash\n"
59 	       "\t-b : the target is big endian (default is little endian)\n"
60 	       "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
61 	       "\t-V : print version information and exit\n"
62 	       "\n"
63 	       "If the input file is \"-\", data is read from standard input\n",
64 	       exec_name);
65 }
66 
67 long int xstrtol(const char *s)
68 {
69 	long int tmp;
70 
71 	errno = 0;
72 	tmp = strtol(s, NULL, 0);
73 	if (!errno)
74 		return tmp;
75 
76 	if (errno == ERANGE)
77 		fprintf(stderr, "Bad integer format: %s\n",  s);
78 	else
79 		fprintf(stderr, "Error while parsing %s: %s\n", s,
80 				strerror(errno));
81 
82 	exit(EXIT_FAILURE);
83 }
84 
85 int main(int argc, char **argv)
86 {
87 	uint32_t crc, targetendian_crc;
88 	const char *txt_filename = NULL, *bin_filename = NULL;
89 	int txt_fd, bin_fd;
90 	unsigned char *dataptr, *envptr;
91 	unsigned char *filebuf = NULL;
92 	unsigned int filesize = 0, envsize = 0, datasize = 0;
93 	int bigendian = 0;
94 	int redundant = 0;
95 	unsigned char padbyte = 0xff;
96 
97 	int option;
98 	int ret = EXIT_SUCCESS;
99 
100 	struct stat txt_file_stat;
101 
102 	int fp, ep;
103 	const char *prg;
104 
105 	prg = basename(argv[0]);
106 
107 	/* Turn off getopt()'s internal error message */
108 	opterr = 0;
109 
110 	/* Parse the cmdline */
111 	while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
112 		switch (option) {
113 		case 's':
114 			datasize = xstrtol(optarg);
115 			break;
116 		case 'o':
117 			bin_filename = strdup(optarg);
118 			if (!bin_filename) {
119 				fprintf(stderr, "Can't strdup() the output filename\n");
120 				return EXIT_FAILURE;
121 			}
122 			break;
123 		case 'r':
124 			redundant = 1;
125 			break;
126 		case 'b':
127 			bigendian = 1;
128 			break;
129 		case 'p':
130 			padbyte = xstrtol(optarg);
131 			break;
132 		case 'h':
133 			usage(prg);
134 			return EXIT_SUCCESS;
135 		case 'V':
136 			printf("%s version %s\n", prg, PLAIN_VERSION);
137 			return EXIT_SUCCESS;
138 		case ':':
139 			fprintf(stderr, "Missing argument for option -%c\n",
140 				optopt);
141 			usage(prg);
142 			return EXIT_FAILURE;
143 		default:
144 			fprintf(stderr, "Wrong option -%c\n", optopt);
145 			usage(prg);
146 			return EXIT_FAILURE;
147 		}
148 	}
149 
150 	/* Check datasize and allocate the data */
151 	if (datasize == 0) {
152 		fprintf(stderr, "Please specify the size of the environment partition.\n");
153 		usage(prg);
154 		return EXIT_FAILURE;
155 	}
156 
157 	dataptr = malloc(datasize * sizeof(*dataptr));
158 	if (!dataptr) {
159 		fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
160 				datasize);
161 		return EXIT_FAILURE;
162 	}
163 
164 	/*
165 	 * envptr points to the beginning of the actual environment (after the
166 	 * crc and possible `redundant' byte
167 	 */
168 	envsize = datasize - (CRC_SIZE + redundant);
169 	envptr = dataptr + CRC_SIZE + redundant;
170 
171 	/* Pad the environment with the padding byte */
172 	memset(envptr, padbyte, envsize);
173 
174 	/* Open the input file ... */
175 	if (optind >= argc || strcmp(argv[optind], "-") == 0) {
176 		int readbytes = 0;
177 		int readlen = sizeof(*envptr) * 4096;
178 		txt_fd = STDIN_FILENO;
179 
180 		do {
181 			filebuf = realloc(filebuf, readlen);
182 			if (!filebuf) {
183 				fprintf(stderr, "Can't realloc memory for the input file buffer\n");
184 				return EXIT_FAILURE;
185 			}
186 			readbytes = read(txt_fd, filebuf + filesize, readlen);
187 			if (errno) {
188 				fprintf(stderr, "Error while reading stdin: %s\n",
189 						strerror(errno));
190 				return EXIT_FAILURE;
191 			}
192 			filesize += readbytes;
193 		} while (readbytes == readlen);
194 
195 	} else {
196 		txt_filename = argv[optind];
197 		txt_fd = open(txt_filename, O_RDONLY);
198 		if (txt_fd == -1) {
199 			fprintf(stderr, "Can't open \"%s\": %s\n",
200 					txt_filename, strerror(errno));
201 			return EXIT_FAILURE;
202 		}
203 		/* ... and check it */
204 		ret = fstat(txt_fd, &txt_file_stat);
205 		if (ret == -1) {
206 			fprintf(stderr, "Can't stat() on \"%s\": %s\n",
207 					txt_filename, strerror(errno));
208 			return EXIT_FAILURE;
209 		}
210 
211 		filesize = txt_file_stat.st_size;
212 
213 		filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
214 			       MAP_PRIVATE, txt_fd, 0);
215 		if (filebuf == MAP_FAILED) {
216 			fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
217 					sizeof(*envptr) * filesize,
218 					strerror(errno));
219 			fprintf(stderr, "Falling back to read()\n");
220 
221 			filebuf = malloc(sizeof(*envptr) * filesize);
222 			ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
223 			if (ret != sizeof(*envptr) * filesize) {
224 				fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
225 					sizeof(*envptr) * filesize,
226 					strerror(errno));
227 
228 				return EXIT_FAILURE;
229 			}
230 		}
231 		ret = close(txt_fd);
232 	}
233 	/* The +1 is for the additionnal ending \0. See below. */
234 	if (filesize + 1 > envsize) {
235 		fprintf(stderr, "The input file is larger than the environment partition size\n");
236 		return EXIT_FAILURE;
237 	}
238 
239 	/* Replace newlines separating variables with \0 */
240 	for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
241 		if (filebuf[fp] == '\n') {
242 			if (ep == 0) {
243 				/*
244 				 * Newlines at the beginning of the file ?
245 				 * Ignore them.
246 				 */
247 				continue;
248 			} else if (filebuf[fp-1] == '\\') {
249 				/*
250 				 * Embedded newline in a variable.
251 				 *
252 				 * The backslash was added to the envptr; rewind
253 				 * and replace it with a newline
254 				 */
255 				ep--;
256 				envptr[ep++] = '\n';
257 			} else {
258 				/* End of a variable */
259 				envptr[ep++] = '\0';
260 			}
261 		} else {
262 			envptr[ep++] = filebuf[fp];
263 		}
264 	}
265 	/*
266 	 * Make sure there is a final '\0'
267 	 * And do it again on the next byte to mark the end of the environment.
268 	 */
269 	if (envptr[ep-1] != '\0') {
270 		envptr[ep++] = '\0';
271 		/*
272 		 * The text file doesn't have an ending newline.  We need to
273 		 * check the env size again to make sure we have room for two \0
274 		 */
275 		if (ep >= envsize) {
276 			fprintf(stderr, "The environment file is too large for the target environment storage\n");
277 			return EXIT_FAILURE;
278 		}
279 		envptr[ep] = '\0';
280 	} else {
281 		envptr[ep] = '\0';
282 	}
283 
284 	/* Computes the CRC and put it at the beginning of the data */
285 	crc = crc32(0, envptr, envsize);
286 	targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
287 
288 	memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
289 	if (redundant)
290 		dataptr[sizeof(targetendian_crc)] = 1;
291 
292 	if (!bin_filename || strcmp(bin_filename, "-") == 0) {
293 		bin_fd = STDOUT_FILENO;
294 	} else {
295 		bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
296 					     S_IWGRP);
297 		if (bin_fd == -1) {
298 			fprintf(stderr, "Can't open output file \"%s\": %s\n",
299 					bin_filename, strerror(errno));
300 			return EXIT_FAILURE;
301 		}
302 	}
303 
304 	if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
305 			sizeof(*dataptr) * datasize) {
306 		fprintf(stderr, "write() failed: %s\n", strerror(errno));
307 		return EXIT_FAILURE;
308 	}
309 
310 	ret = close(bin_fd);
311 
312 	return ret;
313 }
314