1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2011 Free Electrons
4 * David Wagner <david.wagner@free-electrons.com>
5 *
6 * Inspired from envcrc.c:
7 * (C) Copyright 2001
8 * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
9 */
10
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <stdint.h>
16 #include <string.h>
17 #include <unistd.h>
18 #include <libgen.h>
19 #include <sys/types.h>
20 #include <sys/stat.h>
21 #include <sys/mman.h>
22
23 #include "compiler.h"
24 #include <u-boot/crc.h>
25 #include <version.h>
26
27 #define CRC_SIZE sizeof(uint32_t)
28
usage(const char * exec_name)29 static void usage(const char *exec_name)
30 {
31 fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
32 "\n"
33 "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"
34 "\n"
35 "\tThe input file is in format:\n"
36 "\t\tkey1=value1\n"
37 "\t\tkey2=value2\n"
38 "\t\t...\n"
39 "\tEmpty lines are skipped, and lines with a # in the first\n"
40 "\tcolumn are treated as comments (also skipped).\n"
41 "\t-r : the environment has multiple copies in flash\n"
42 "\t-b : the target is big endian (default is little endian)\n"
43 "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
44 "\t-V : print version information and exit\n"
45 "\n"
46 "If the input file is \"-\", data is read from standard input\n",
47 exec_name);
48 }
49
xstrtol(const char * s)50 long int xstrtol(const char *s)
51 {
52 long int tmp;
53
54 errno = 0;
55 tmp = strtol(s, NULL, 0);
56 if (!errno)
57 return tmp;
58
59 if (errno == ERANGE)
60 fprintf(stderr, "Bad integer format: %s\n", s);
61 else
62 fprintf(stderr, "Error while parsing %s: %s\n", s,
63 strerror(errno));
64
65 exit(EXIT_FAILURE);
66 }
67
main(int argc,char ** argv)68 int main(int argc, char **argv)
69 {
70 uint32_t crc, targetendian_crc;
71 const char *txt_filename = NULL, *bin_filename = NULL;
72 int txt_fd, bin_fd;
73 unsigned char *dataptr, *envptr;
74 unsigned char *filebuf = NULL;
75 unsigned int filesize = 0, envsize = 0, datasize = 0;
76 int bigendian = 0;
77 int redundant = 0;
78 unsigned char padbyte = 0xff;
79
80 int option;
81 int ret = EXIT_SUCCESS;
82
83 struct stat txt_file_stat;
84
85 int fp, ep;
86 const char *prg;
87
88 prg = basename(argv[0]);
89
90 /* Turn off getopt()'s internal error message */
91 opterr = 0;
92
93 /* Parse the cmdline */
94 while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
95 switch (option) {
96 case 's':
97 datasize = xstrtol(optarg);
98 break;
99 case 'o':
100 bin_filename = strdup(optarg);
101 if (!bin_filename) {
102 fprintf(stderr, "Can't strdup() the output filename\n");
103 return EXIT_FAILURE;
104 }
105 break;
106 case 'r':
107 redundant = 1;
108 break;
109 case 'b':
110 bigendian = 1;
111 break;
112 case 'p':
113 padbyte = xstrtol(optarg);
114 break;
115 case 'h':
116 usage(prg);
117 return EXIT_SUCCESS;
118 case 'V':
119 printf("%s version %s\n", prg, PLAIN_VERSION);
120 return EXIT_SUCCESS;
121 case ':':
122 fprintf(stderr, "Missing argument for option -%c\n",
123 optopt);
124 usage(prg);
125 return EXIT_FAILURE;
126 default:
127 fprintf(stderr, "Wrong option -%c\n", optopt);
128 usage(prg);
129 return EXIT_FAILURE;
130 }
131 }
132
133 /* Check datasize and allocate the data */
134 if (datasize == 0) {
135 fprintf(stderr, "Please specify the size of the environment partition.\n");
136 usage(prg);
137 return EXIT_FAILURE;
138 }
139
140 dataptr = malloc(datasize * sizeof(*dataptr));
141 if (!dataptr) {
142 fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
143 datasize);
144 return EXIT_FAILURE;
145 }
146
147 /*
148 * envptr points to the beginning of the actual environment (after the
149 * crc and possible `redundant' byte
150 */
151 envsize = datasize - (CRC_SIZE + redundant);
152 envptr = dataptr + CRC_SIZE + redundant;
153
154 /* Pad the environment with the padding byte */
155 memset(envptr, padbyte, envsize);
156
157 /* Open the input file ... */
158 if (optind >= argc || strcmp(argv[optind], "-") == 0) {
159 int readbytes = 0;
160 int readlen = sizeof(*envptr) * 4096;
161 txt_fd = STDIN_FILENO;
162
163 do {
164 filebuf = realloc(filebuf, filesize + readlen);
165 if (!filebuf) {
166 fprintf(stderr, "Can't realloc memory for the input file buffer\n");
167 return EXIT_FAILURE;
168 }
169 readbytes = read(txt_fd, filebuf + filesize, readlen);
170 if (readbytes < 0) {
171 fprintf(stderr, "Error while reading stdin: %s\n",
172 strerror(errno));
173 return EXIT_FAILURE;
174 }
175 filesize += readbytes;
176 } while (readbytes == readlen);
177
178 } else {
179 txt_filename = argv[optind];
180 txt_fd = open(txt_filename, O_RDONLY);
181 if (txt_fd == -1) {
182 fprintf(stderr, "Can't open \"%s\": %s\n",
183 txt_filename, strerror(errno));
184 return EXIT_FAILURE;
185 }
186 /* ... and check it */
187 ret = fstat(txt_fd, &txt_file_stat);
188 if (ret == -1) {
189 fprintf(stderr, "Can't stat() on \"%s\": %s\n",
190 txt_filename, strerror(errno));
191 return EXIT_FAILURE;
192 }
193
194 filesize = txt_file_stat.st_size;
195
196 filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
197 MAP_PRIVATE, txt_fd, 0);
198 if (filebuf == MAP_FAILED) {
199 fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
200 sizeof(*envptr) * filesize,
201 strerror(errno));
202 fprintf(stderr, "Falling back to read()\n");
203
204 filebuf = malloc(sizeof(*envptr) * filesize);
205 ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
206 if (ret != sizeof(*envptr) * filesize) {
207 fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
208 sizeof(*envptr) * filesize,
209 strerror(errno));
210
211 return EXIT_FAILURE;
212 }
213 }
214 ret = close(txt_fd);
215 }
216
217 /* Parse a byte at time until reaching the file OR until the environment fills
218 * up. Check ep against envsize - 1 to allow for extra trailing '\0'. */
219 for (fp = 0, ep = 0 ; fp < filesize && ep < envsize - 1; fp++) {
220 if (filebuf[fp] == '\n') {
221 if (fp == 0 || filebuf[fp-1] == '\n') {
222 /*
223 * Skip empty lines.
224 */
225 continue;
226 } else if (filebuf[fp-1] == '\\') {
227 /*
228 * Embedded newline in a variable.
229 *
230 * The backslash was added to the envptr; rewind
231 * and replace it with a newline
232 */
233 ep--;
234 envptr[ep++] = '\n';
235 } else {
236 /* End of a variable */
237 envptr[ep++] = '\0';
238 }
239 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
240 /* Comment, skip the line. */
241 while (++fp < filesize && filebuf[fp] != '\n')
242 continue;
243 } else {
244 envptr[ep++] = filebuf[fp];
245 }
246 }
247 /* If there are more bytes in the file still, it means the env filled up
248 * before parsing the whole file. Eat comments & whitespace here to see if
249 * there was anything meaning full left in the file, and if so, throw a error
250 * and exit. */
251 for( ; fp < filesize; fp++ )
252 {
253 if (filebuf[fp] == '\n') {
254 if (fp == 0 || filebuf[fp-1] == '\n') {
255 /* Ignore blank lines */
256 continue;
257 }
258 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
259 while (++fp < filesize && filebuf[fp] != '\n')
260 continue;
261 } else {
262 fprintf(stderr, "The environment file is too large for the target environment storage\n");
263 return EXIT_FAILURE;
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