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] [-V] [-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 static 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
68 #define CHUNK_SIZE 4096
69
main(int argc,char ** argv)70 int main(int argc, char **argv)
71 {
72 uint32_t crc, targetendian_crc;
73 const char *bin_filename = NULL;
74 int txt_fd, bin_fd;
75 unsigned char *dataptr, *envptr;
76 unsigned char *filebuf = NULL;
77 unsigned int filesize = 0, envsize = 0, datasize = 0;
78 int bigendian = 0;
79 int redundant = 0;
80 unsigned char padbyte = 0xff;
81 int readbytes = 0;
82
83 int option;
84 int ret = EXIT_SUCCESS;
85
86 int fp, ep;
87 const char *prg;
88
89 prg = basename(argv[0]);
90
91 /* Turn off getopt()'s internal error message */
92 opterr = 0;
93
94 /* Parse the cmdline */
95 while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
96 switch (option) {
97 case 's':
98 datasize = xstrtol(optarg);
99 break;
100 case 'o':
101 bin_filename = strdup(optarg);
102 if (!bin_filename) {
103 fprintf(stderr, "Can't strdup() the output filename\n");
104 return EXIT_FAILURE;
105 }
106 break;
107 case 'r':
108 redundant = 1;
109 break;
110 case 'b':
111 bigendian = 1;
112 break;
113 case 'p':
114 padbyte = xstrtol(optarg);
115 break;
116 case 'h':
117 usage(prg);
118 return EXIT_SUCCESS;
119 case 'V':
120 printf("%s version %s\n", prg, PLAIN_VERSION);
121 return EXIT_SUCCESS;
122 case ':':
123 fprintf(stderr, "Missing argument for option -%c\n",
124 optopt);
125 usage(prg);
126 return EXIT_FAILURE;
127 default:
128 fprintf(stderr, "Wrong option -%c\n", optopt);
129 usage(prg);
130 return EXIT_FAILURE;
131 }
132 }
133
134 /* Check datasize and allocate the data */
135 if (datasize == 0) {
136 fprintf(stderr, "Please specify the size of the environment partition.\n");
137 usage(prg);
138 return EXIT_FAILURE;
139 }
140
141 dataptr = malloc(datasize * sizeof(*dataptr));
142 if (!dataptr) {
143 fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
144 datasize);
145 return EXIT_FAILURE;
146 }
147
148 /*
149 * envptr points to the beginning of the actual environment (after the
150 * crc and possible `redundant' byte
151 */
152 envsize = datasize - (CRC_SIZE + redundant);
153 envptr = dataptr + CRC_SIZE + redundant;
154
155 /* Pad the environment with the padding byte */
156 memset(envptr, padbyte, envsize);
157
158 /* Open the input file ... */
159 if (optind >= argc || strcmp(argv[optind], "-") == 0) {
160 txt_fd = STDIN_FILENO;
161 } else {
162 txt_fd = open(argv[optind], O_RDONLY);
163 if (txt_fd == -1) {
164 fprintf(stderr, "Can't open \"%s\": %s\n",
165 argv[optind], strerror(errno));
166 return EXIT_FAILURE;
167 }
168 }
169
170 do {
171 filebuf = realloc(filebuf, filesize + CHUNK_SIZE);
172 if (!filebuf) {
173 fprintf(stderr, "Can't realloc memory for the input file buffer\n");
174 return EXIT_FAILURE;
175 }
176 readbytes = read(txt_fd, filebuf + filesize, CHUNK_SIZE);
177 if (readbytes < 0) {
178 fprintf(stderr, "Error while reading: %s\n",
179 strerror(errno));
180 return EXIT_FAILURE;
181 }
182 filesize += readbytes;
183 } while (readbytes > 0);
184
185 if (txt_fd != STDIN_FILENO)
186 ret = close(txt_fd);
187
188 /* Parse a byte at time until reaching the file OR until the environment fills
189 * up. Check ep against envsize - 1 to allow for extra trailing '\0'. */
190 for (fp = 0, ep = 0 ; fp < filesize && ep < envsize - 1; fp++) {
191 if (filebuf[fp] == '\n') {
192 if (fp == 0 || filebuf[fp-1] == '\n') {
193 /*
194 * Skip empty lines.
195 */
196 continue;
197 } else if (filebuf[fp-1] == '\\') {
198 /*
199 * Embedded newline in a variable.
200 *
201 * The backslash was added to the envptr; rewind
202 * and replace it with a newline
203 */
204 ep--;
205 envptr[ep++] = '\n';
206 } else {
207 /* End of a variable */
208 envptr[ep++] = '\0';
209 }
210 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
211 /* Comment, skip the line. */
212 while (++fp < filesize && filebuf[fp] != '\n')
213 continue;
214 } else {
215 envptr[ep++] = filebuf[fp];
216 }
217 }
218 /* If there are more bytes in the file still, it means the env filled up
219 * before parsing the whole file. Eat comments & whitespace here to see if
220 * there was anything meaning full left in the file, and if so, throw a error
221 * and exit. */
222 for( ; fp < filesize; fp++ )
223 {
224 if (filebuf[fp] == '\n') {
225 if (fp == 0 || filebuf[fp-1] == '\n') {
226 /* Ignore blank lines */
227 continue;
228 }
229 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
230 while (++fp < filesize && filebuf[fp] != '\n')
231 continue;
232 } else {
233 fprintf(stderr, "The environment file is too large for the target environment storage\n");
234 return EXIT_FAILURE;
235 }
236 }
237 /*
238 * Make sure there is a final '\0'
239 * And do it again on the next byte to mark the end of the environment.
240 */
241 if (envptr[ep-1] != '\0') {
242 envptr[ep++] = '\0';
243 /*
244 * The text file doesn't have an ending newline. We need to
245 * check the env size again to make sure we have room for two \0
246 */
247 if (ep >= envsize) {
248 fprintf(stderr, "The environment file is too large for the target environment storage\n");
249 return EXIT_FAILURE;
250 }
251 envptr[ep] = '\0';
252 } else {
253 envptr[ep] = '\0';
254 }
255
256 /* Computes the CRC and put it at the beginning of the data */
257 crc = crc32(0, envptr, envsize);
258 targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
259
260 memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
261 if (redundant)
262 dataptr[sizeof(targetendian_crc)] = 1;
263
264 if (!bin_filename || strcmp(bin_filename, "-") == 0) {
265 bin_fd = STDOUT_FILENO;
266 } else {
267 bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
268 S_IWGRP);
269 if (bin_fd == -1) {
270 fprintf(stderr, "Can't open output file \"%s\": %s\n",
271 bin_filename, strerror(errno));
272 return EXIT_FAILURE;
273 }
274 }
275
276 if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
277 sizeof(*dataptr) * datasize) {
278 fprintf(stderr, "write() failed: %s\n", strerror(errno));
279 return EXIT_FAILURE;
280 }
281
282 ret = close(bin_fd);
283
284 return ret;
285 }
286