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 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 12 #include <errno.h> 13 #include <fcntl.h> 14 #include <stdio.h> 15 #include <stdlib.h> 16 #include <stdint.h> 17 #include <string.h> 18 #include <unistd.h> 19 #include <libgen.h> 20 #include <sys/types.h> 21 #include <sys/stat.h> 22 #include <sys/mman.h> 23 24 #include "compiler.h" 25 #include <u-boot/crc.h> 26 #include <version.h> 27 28 #define CRC_SIZE sizeof(uint32_t) 29 30 static void usage(const char *exec_name) 31 { 32 fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n" 33 "\n" 34 "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" 35 "\n" 36 "\tThe input file is in format:\n" 37 "\t\tkey1=value1\n" 38 "\t\tkey2=value2\n" 39 "\t\t...\n" 40 "\tEmpty lines are skipped, and lines with a # in the first\n" 41 "\tcolumn are treated as comments (also skipped).\n" 42 "\t-r : the environment has multiple copies in flash\n" 43 "\t-b : the target is big endian (default is little endian)\n" 44 "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n" 45 "\t-V : print version information and exit\n" 46 "\n" 47 "If the input file is \"-\", data is read from standard input\n", 48 exec_name); 49 } 50 51 long int xstrtol(const char *s) 52 { 53 long int tmp; 54 55 errno = 0; 56 tmp = strtol(s, NULL, 0); 57 if (!errno) 58 return tmp; 59 60 if (errno == ERANGE) 61 fprintf(stderr, "Bad integer format: %s\n", s); 62 else 63 fprintf(stderr, "Error while parsing %s: %s\n", s, 64 strerror(errno)); 65 66 exit(EXIT_FAILURE); 67 } 68 69 int main(int argc, char **argv) 70 { 71 uint32_t crc, targetendian_crc; 72 const char *txt_filename = NULL, *bin_filename = NULL; 73 int txt_fd, bin_fd; 74 unsigned char *dataptr, *envptr; 75 unsigned char *filebuf = NULL; 76 unsigned int filesize = 0, envsize = 0, datasize = 0; 77 int bigendian = 0; 78 int redundant = 0; 79 unsigned char padbyte = 0xff; 80 81 int option; 82 int ret = EXIT_SUCCESS; 83 84 struct stat txt_file_stat; 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 int readbytes = 0; 161 int readlen = sizeof(*envptr) * 4096; 162 txt_fd = STDIN_FILENO; 163 164 do { 165 filebuf = realloc(filebuf, readlen); 166 if (!filebuf) { 167 fprintf(stderr, "Can't realloc memory for the input file buffer\n"); 168 return EXIT_FAILURE; 169 } 170 readbytes = read(txt_fd, filebuf + filesize, readlen); 171 if (errno) { 172 fprintf(stderr, "Error while reading stdin: %s\n", 173 strerror(errno)); 174 return EXIT_FAILURE; 175 } 176 filesize += readbytes; 177 } while (readbytes == readlen); 178 179 } else { 180 txt_filename = argv[optind]; 181 txt_fd = open(txt_filename, O_RDONLY); 182 if (txt_fd == -1) { 183 fprintf(stderr, "Can't open \"%s\": %s\n", 184 txt_filename, strerror(errno)); 185 return EXIT_FAILURE; 186 } 187 /* ... and check it */ 188 ret = fstat(txt_fd, &txt_file_stat); 189 if (ret == -1) { 190 fprintf(stderr, "Can't stat() on \"%s\": %s\n", 191 txt_filename, strerror(errno)); 192 return EXIT_FAILURE; 193 } 194 195 filesize = txt_file_stat.st_size; 196 197 filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ, 198 MAP_PRIVATE, txt_fd, 0); 199 if (filebuf == MAP_FAILED) { 200 fprintf(stderr, "mmap (%zu bytes) failed: %s\n", 201 sizeof(*envptr) * filesize, 202 strerror(errno)); 203 fprintf(stderr, "Falling back to read()\n"); 204 205 filebuf = malloc(sizeof(*envptr) * filesize); 206 ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize); 207 if (ret != sizeof(*envptr) * filesize) { 208 fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n", 209 sizeof(*envptr) * filesize, 210 strerror(errno)); 211 212 return EXIT_FAILURE; 213 } 214 } 215 ret = close(txt_fd); 216 } 217 218 /* Parse a byte at time until reaching the file OR until the environment fills 219 * up. Check ep against envsize - 1 to allow for extra trailing '\0'. */ 220 for (fp = 0, ep = 0 ; fp < filesize && ep < envsize - 1; fp++) { 221 if (filebuf[fp] == '\n') { 222 if (fp == 0 || filebuf[fp-1] == '\n') { 223 /* 224 * Skip empty lines. 225 */ 226 continue; 227 } else if (filebuf[fp-1] == '\\') { 228 /* 229 * Embedded newline in a variable. 230 * 231 * The backslash was added to the envptr; rewind 232 * and replace it with a newline 233 */ 234 ep--; 235 envptr[ep++] = '\n'; 236 } else { 237 /* End of a variable */ 238 envptr[ep++] = '\0'; 239 } 240 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') { 241 /* Comment, skip the line. */ 242 while (++fp < filesize && filebuf[fp] != '\n') 243 continue; 244 } else { 245 envptr[ep++] = filebuf[fp]; 246 } 247 } 248 /* If there are more bytes in the file still, it means the env filled up 249 * before parsing the whole file. Eat comments & whitespace here to see if 250 * there was anything meaning full left in the file, and if so, throw a error 251 * and exit. */ 252 for( ; fp < filesize; fp++ ) 253 { 254 if (filebuf[fp] == '\n') { 255 if (fp == 0 || filebuf[fp-1] == '\n') { 256 /* Ignore blank lines */ 257 continue; 258 } 259 } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') { 260 while (++fp < filesize && filebuf[fp] != '\n') 261 continue; 262 } else { 263 fprintf(stderr, "The environment file is too large for the target environment storage\n"); 264 return EXIT_FAILURE; 265 } 266 } 267 /* 268 * Make sure there is a final '\0' 269 * And do it again on the next byte to mark the end of the environment. 270 */ 271 if (envptr[ep-1] != '\0') { 272 envptr[ep++] = '\0'; 273 /* 274 * The text file doesn't have an ending newline. We need to 275 * check the env size again to make sure we have room for two \0 276 */ 277 if (ep >= envsize) { 278 fprintf(stderr, "The environment file is too large for the target environment storage\n"); 279 return EXIT_FAILURE; 280 } 281 envptr[ep] = '\0'; 282 } else { 283 envptr[ep] = '\0'; 284 } 285 286 /* Computes the CRC and put it at the beginning of the data */ 287 crc = crc32(0, envptr, envsize); 288 targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc); 289 290 memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc)); 291 if (redundant) 292 dataptr[sizeof(targetendian_crc)] = 1; 293 294 if (!bin_filename || strcmp(bin_filename, "-") == 0) { 295 bin_fd = STDOUT_FILENO; 296 } else { 297 bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP | 298 S_IWGRP); 299 if (bin_fd == -1) { 300 fprintf(stderr, "Can't open output file \"%s\": %s\n", 301 bin_filename, strerror(errno)); 302 return EXIT_FAILURE; 303 } 304 } 305 306 if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) != 307 sizeof(*dataptr) * datasize) { 308 fprintf(stderr, "write() failed: %s\n", strerror(errno)); 309 return EXIT_FAILURE; 310 } 311 312 ret = close(bin_fd); 313 314 return ret; 315 } 316