tools/firmware-utils/src/mkwrgimg.c

   1 /*
   2  *  Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
   3  *
   4  *  This program is free software; you can redistribute it and/or modify it
   5  *  under the terms of the GNU General Public License version 2 as published
   6  *  by the Free Software Foundation.
   7  *
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <stdint.h>
  13 #include <string.h>
  14 #include <unistd.h>
  15 #include <libgen.h>
  16 #include <getopt.h>
  17 #include <stdarg.h>
  18 #include <errno.h>
  19 #include <sys/stat.h>
  20
  21 #include "md5.h"
  22
  23 #define ERR(fmt, ...) do { \
  24         fflush(0); \
  25         fprintf(stderr, "[%s] *** error: " fmt "\n", \
  26                         progname, ## __VA_ARGS__ ); \
  27 } while (0)
  28
  29 #define ERRS(fmt, ...) do { \
  30         int save = errno; \
  31         fflush(0); \
  32         fprintf(stderr, "[%s] *** error: " fmt ", %s\n", \
  33                         progname, ## __VA_ARGS__, strerror(save)); \
  34 } while (0)
  35
  36 #define WRG_MAGIC       0x20040220
  37
  38 struct wrg_header {
  39         char            signature[32];
  40         uint32_t        magic1;
  41         uint32_t        magic2;
  42         uint32_t        size;
  43         uint32_t        offset;
  44         char            devname[32];
  45         char            digest[16];
  46 } __attribute__ ((packed));
  47
  48 static char *progname;
  49 static char *ifname;
  50 static char *ofname;
  51 static char *signature;
  52 static char *dev_name;
  53 static uint32_t offset;
  54 static int big_endian;
  55
  56 void usage(int status)
  57 {
  58         FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout;
  59
  60         fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
  61         fprintf(stream,
  62 "\n"
  63 "Options:\n"
  64 "  -b              create image in big endian format\n"
  65 "  -i <file>       read input from the file <file>\n"
  66 "  -d <name>       set device name to <name>\n"
  67 "  -o <file>       write output to the file <file>\n"
  68 "  -O <offset>     set offset to <offset>\n"
  69 "  -s <sig>        set image signature to <sig>\n"
  70 "  -h              show this screen\n"
  71         );
  72
  73         exit(status);
  74 }
  75
  76 static void put_u32(void *data, uint32_t val)
  77 {
  78         unsigned char *p = data;
  79
  80         if (big_endian) {
  81                 p[0] = (val >> 24) & 0xff;
  82                 p[1] = (val >> 16) & 0xff;
  83                 p[2] = (val >> 8) & 0xff;
  84                 p[3] = val & 0xff;
  85         } else {
  86                 p[3] = (val >> 24) & 0xff;
  87                 p[2] = (val >> 16) & 0xff;
  88                 p[1] = (val >> 8) & 0xff;
  89                 p[0] = val & 0xff;
  90         }
  91 }
  92
  93 static void get_digest(struct wrg_header *header, char *data, int size)
  94 {
  95         MD5_CTX ctx;
  96
  97         MD5_Init(&ctx);
  98
  99         MD5_Update(&ctx, (char *)&header->offset, sizeof(header->offset));
 100         MD5_Update(&ctx, (char *)&header->devname, sizeof(header->devname));
 101         MD5_Update(&ctx, data, size);
 102
 103         MD5_Final((unsigned char *)header->digest, &ctx);
 104 }
 105
 106 int main(int argc, char *argv[])
 107 {
 108         struct wrg_header *header;
 109         char *buf;
 110         struct stat st;
 111         int buflen;
 112         int err;
 113         int res = EXIT_FAILURE;
 114
 115         FILE *outfile, *infile;
 116
 117         progname = basename(argv[0]);
 118
 119         while ( 1 ) {
 120                 int c;
 121
 122                 c = getopt(argc, argv, "bd:i:o:s:O:h");
 123                 if (c == -1)
 124                         break;
 125
 126                 switch (c) {
 127                 case 'b':
 128                         big_endian = 1;
 129                         break;
 130                 case 'd':
 131                         dev_name = optarg;
 132                         break;
 133                 case 'i':
 134                         ifname = optarg;
 135                         break;
 136                 case 'o':
 137                         ofname = optarg;
 138                         break;
 139                 case 's':
 140                         signature = optarg;
 141                         break;
 142                 case 'O':
 143                         offset = strtoul(optarg, NULL, 0);
 144                         break;
 145                 case 'h':
 146                         usage(EXIT_SUCCESS);
 147                         break;
 148
 149                 default:
 150                         usage(EXIT_FAILURE);
 151                         break;
 152                 }
 153         }
 154
 155         if (signature == NULL) {
 156                 ERR("no signature specified");
 157                 goto err;
 158         }
 159
 160         if (ifname == NULL) {
 161                 ERR("no input file specified");
 162                 goto err;
 163         }
 164
 165         if (ofname == NULL) {
 166                 ERR("no output file specified");
 167                 goto err;
 168         }
 169
 170         if (dev_name == NULL) {
 171                 ERR("no device name specified");
 172                 goto err;
 173         }
 174
 175         err = stat(ifname, &st);
 176         if (err){
 177                 ERRS("stat failed on %s", ifname);
 178                 goto err;
 179         }
 180
 181         buflen = st.st_size + sizeof(struct wrg_header);
 182         buf = malloc(buflen);
 183         if (!buf) {
 184                 ERR("no memory for buffer\n");
 185                 goto err;
 186         }
 187
 188         infile = fopen(ifname, "r");
 189         if (infile == NULL) {
 190                 ERRS("could not open \"%s\" for reading", ifname);
 191                 goto err_free;
 192         }
 193
 194         errno = 0;
 195         fread(buf + sizeof(struct wrg_header), st.st_size, 1, infile);
 196         if (errno != 0) {
 197                 ERRS("unable to read from file %s", ifname);
 198                 goto close_in;
 199         }
 200
 201         header = (struct wrg_header *) buf;
 202         memset(header, '\0', sizeof(struct wrg_header));
 203
 204         strncpy(header->signature, signature, sizeof(header->signature));
 205         strncpy(header->devname, dev_name, sizeof(header->signature));
 206         put_u32(&header->magic1, WRG_MAGIC);
 207         put_u32(&header->magic2, WRG_MAGIC);
 208         put_u32(&header->size, st.st_size);
 209         put_u32(&header->offset, offset);
 210
 211         get_digest(header, buf + sizeof(struct wrg_header), st.st_size);
 212
 213         outfile = fopen(ofname, "w");
 214         if (outfile == NULL) {
 215                 ERRS("could not open \"%s\" for writing", ofname);
 216                 goto close_in;
 217         }
 218
 219         errno = 0;
 220         fwrite(buf, buflen, 1, outfile);
 221         if (errno) {
 222                 ERRS("unable to write to file %s", ofname);
 223                 goto close_out;
 224         }
 225
 226         fflush(outfile);
 227
 228         res = EXIT_SUCCESS;
 229
 230 close_out:
 231         fclose(outfile);
 232         if (res != EXIT_SUCCESS)
 233                 unlink(ofname);
 234 close_in:
 235         fclose(infile);
 236 err_free:
 237         free(buf);
 238 err:
 239         return res;
 240 }