LXR uboot/tools/mkenvimage.c

   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 <u-boot/crc.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
  30static 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
  51long 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#define CHUNK_SIZE 4096
  70
  71int main(int argc, char **argv)
  72{
  73        uint32_t crc, targetendian_crc;
  74        const char *bin_filename = NULL;
  75        int txt_fd, bin_fd;
  76        unsigned char *dataptr, *envptr;
  77        unsigned char *filebuf = NULL;
  78        unsigned int filesize = 0, envsize = 0, datasize = 0;
  79        int bigendian = 0;
  80        int redundant = 0;
  81        unsigned char padbyte = 0xff;
  82        int readbytes = 0;
  83
  84        int option;
  85        int ret = EXIT_SUCCESS;
  86
  87        int fp, ep;
  88        const char *prg;
  89
  90        prg = basename(argv[0]);
  91
  92        /* Turn off getopt()'s internal error message */
  93        opterr = 0;
  94
  95        /* Parse the cmdline */
  96        while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
  97                switch (option) {
  98                case 's':
  99                        datasize = xstrtol(optarg);
 100                        break;
 101                case 'o':
 102                        bin_filename = strdup(optarg);
 103                        if (!bin_filename) {
 104                                fprintf(stderr, "Can't strdup() the output filename\n");
 105                                return EXIT_FAILURE;
 106                        }
 107                        break;
 108                case 'r':
 109                        redundant = 1;
 110                        break;
 111                case 'b':
 112                        bigendian = 1;
 113                        break;
 114                case 'p':
 115                        padbyte = xstrtol(optarg);
 116                        break;
 117                case 'h':
 118                        usage(prg);
 119                        return EXIT_SUCCESS;
 120                case 'V':
 121                        printf("%s version %s\n", prg, PLAIN_VERSION);
 122                        return EXIT_SUCCESS;
 123                case ':':
 124                        fprintf(stderr, "Missing argument for option -%c\n",
 125                                optopt);
 126                        usage(prg);
 127                        return EXIT_FAILURE;
 128                default:
 129                        fprintf(stderr, "Wrong option -%c\n", optopt);
 130                        usage(prg);
 131                        return EXIT_FAILURE;
 132                }
 133        }
 134
 135        /* Check datasize and allocate the data */
 136        if (datasize == 0) {
 137                fprintf(stderr, "Please specify the size of the environment partition.\n");
 138                usage(prg);
 139                return EXIT_FAILURE;
 140        }
 141
 142        dataptr = malloc(datasize * sizeof(*dataptr));
 143        if (!dataptr) {
 144                fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
 145                                datasize);
 146                return EXIT_FAILURE;
 147        }
 148
 149        /*
 150         * envptr points to the beginning of the actual environment (after the
 151         * crc and possible `redundant' byte
 152         */
 153        envsize = datasize - (CRC_SIZE + redundant);
 154        envptr = dataptr + CRC_SIZE + redundant;
 155
 156        /* Pad the environment with the padding byte */
 157        memset(envptr, padbyte, envsize);
 158
 159        /* Open the input file ... */
 160        if (optind >= argc || strcmp(argv[optind], "-") == 0) {
 161                txt_fd = STDIN_FILENO;
 162        } else {
 163                txt_fd = open(argv[optind], O_RDONLY);
 164                if (txt_fd == -1) {
 165                        fprintf(stderr, "Can't open \"%s\": %s\n",
 166                                        argv[optind], strerror(errno));
 167                        return EXIT_FAILURE;
 168                }
 169        }
 170
 171        do {
 172                filebuf = realloc(filebuf, filesize + CHUNK_SIZE);
 173                if (!filebuf) {
 174                        fprintf(stderr, "Can't realloc memory for the input file buffer\n");
 175                        return EXIT_FAILURE;
 176                }
 177                readbytes = read(txt_fd, filebuf + filesize, CHUNK_SIZE);
 178                if (readbytes < 0) {
 179                        fprintf(stderr, "Error while reading: %s\n",
 180                                strerror(errno));
 181                        return EXIT_FAILURE;
 182                }
 183                filesize += readbytes;
 184        } while (readbytes > 0);
 185
 186        if (txt_fd != STDIN_FILENO)
 187                ret = close(txt_fd);
 188
 189        /* Parse a byte at time until reaching the file OR until the environment fills
 190         * up. Check ep against envsize - 1 to allow for extra trailing '\0'. */
 191        for (fp = 0, ep = 0 ; fp < filesize && ep < envsize - 1; fp++) {
 192                if (filebuf[fp] == '\n') {
 193                        if (fp == 0 || filebuf[fp-1] == '\n') {
 194                                /*
 195                                 * Skip empty lines.
 196                                 */
 197                                continue;
 198                        } else if (filebuf[fp-1] == '\\') {
 199                                /*
 200                                 * Embedded newline in a variable.
 201                                 *
 202                                 * The backslash was added to the envptr; rewind
 203                                 * and replace it with a newline
 204                                 */
 205                                ep--;
 206                                envptr[ep++] = '\n';
 207                        } else {
 208                                /* End of a variable */
 209                                envptr[ep++] = '\0';
 210                        }
 211                } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
 212                        /* Comment, skip the line. */
 213                        while (++fp < filesize && filebuf[fp] != '\n')
 214                        continue;
 215                } else {
 216                        envptr[ep++] = filebuf[fp];
 217                }
 218        }
 219        /* If there are more bytes in the file still, it means the env filled up
 220         * before parsing the whole file.  Eat comments & whitespace here to see if
 221         * there was anything meaning full left in the file, and if so, throw a error
 222         * and exit. */
 223        for( ; fp < filesize; fp++ )
 224        {
 225                if (filebuf[fp] == '\n') {
 226                        if (fp == 0 || filebuf[fp-1] == '\n') {
 227                                /* Ignore blank lines */
 228                                continue;
 229                        }
 230                } else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
 231                        while (++fp < filesize && filebuf[fp] != '\n')
 232                        continue;
 233                } else {
 234                        fprintf(stderr, "The environment file is too large for the target environment storage\n");
 235                        return EXIT_FAILURE;
 236                }
 237        }
 238        /*
 239         * Make sure there is a final '\0'
 240         * And do it again on the next byte to mark the end of the environment.
 241         */
 242        if (envptr[ep-1] != '\0') {
 243                envptr[ep++] = '\0';
 244                /*
 245                 * The text file doesn't have an ending newline.  We need to
 246                 * check the env size again to make sure we have room for two \0
 247                 */
 248                if (ep >= envsize) {
 249                        fprintf(stderr, "The environment file is too large for the target environment storage\n");
 250                        return EXIT_FAILURE;
 251                }
 252                envptr[ep] = '\0';
 253        } else {
 254                envptr[ep] = '\0';
 255        }
 256
 257        /* Computes the CRC and put it at the beginning of the data */
 258        crc = crc32(0, envptr, envsize);
 259        targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
 260
 261        memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
 262        if (redundant)
 263                dataptr[sizeof(targetendian_crc)] = 1;
 264
 265        if (!bin_filename || strcmp(bin_filename, "-") == 0) {
 266                bin_fd = STDOUT_FILENO;
 267        } else {
 268                bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
 269                                             S_IWGRP);
 270                if (bin_fd == -1) {
 271                        fprintf(stderr, "Can't open output file \"%s\": %s\n",
 272                                        bin_filename, strerror(errno));
 273                        return EXIT_FAILURE;
 274                }
 275        }
 276
 277        if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
 278                        sizeof(*dataptr) * datasize) {
 279                fprintf(stderr, "write() failed: %s\n", strerror(errno));
 280                return EXIT_FAILURE;
 281        }
 282
 283        ret = close(bin_fd);
 284
 285        return ret;
 286}
 287