tools/firmware-utils/src/motorola-bin.c

   1 /*
   2  * motorola-bin.c
   3  *
   4  * Copyright (C) 2005-2006 Mike Baker,
   5  *                         Imre Kaloz <kaloz@openwrt.org>
   6  *                         D. Hugh Redelmeier
   7  *                         OpenWrt.org
   8  *
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  23  *
  24  */
  25
  26 /*
  27  * Motorola's firmware flashing code requires an extra header.
  28  * The header is eight bytes (see struct motorola below).
  29  * This program will take a firmware file and create a new one
  30  * with this header:
  31  *      motorola-bin --wr850g WR850G_V403.stripped.trx WR850G_V403.trx
  32  *
  33  * Note: Motorola's firmware is distributed with this header.
  34  * If you need to flash Motorola firmware on a router running OpenWRT,
  35  * you will to remove this header.  Use the --strip flag:
  36  *      motorola-bin --strip WR850G_V403.trx WR850G_V403.stripped.trx
  37  */
  38
  39 /*
  40  * February 1, 2006
  41  *
  42  * Add support for for creating WA840G and WE800G images
  43  */
  44
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <stddef.h>
  48 #include <unistd.h>
  49 #include <errno.h>
  50 #include <fcntl.h>
  51 #include <sys/mman.h>
  52 #include <string.h>
  53 #include <netinet/in.h>
  54 #include <inttypes.h>
  55
  56 #define BPB 8 /* bits/byte */
  57
  58 static uint32_t crc32[1<<BPB];
  59
  60 static void init_crc32()
  61 {
  62         const uint32_t poly = ntohl(0x2083b8ed);
  63         int n;
  64
  65         for (n = 0; n < 1<<BPB; n++) {
  66                 uint32_t crc = n;
  67                 int bit;
  68
  69                 for (bit = 0; bit < BPB; bit++)
  70                         crc = (crc & 1) ? (poly ^ (crc >> 1)) : (crc >> 1);
  71                 crc32[n] = crc;
  72         }
  73 }
  74
  75 static uint32_t crc32buf(unsigned char *buf, size_t len)
  76 {
  77         uint32_t crc = 0xFFFFFFFF;
  78
  79         for (; len; len--, buf++)
  80                 crc = crc32[(uint8_t)crc ^ *buf] ^ (crc >> BPB);
  81         return crc;
  82 }
  83
  84 struct motorola {
  85         uint32_t crc;   // crc32 of the remainder
  86         uint32_t flags; // unknown, 105770*
  87 };
  88
  89 static const struct model {
  90         char digit;     /* a digit signifying model (historical) */
  91         const char *name;
  92         uint32_t flags;
  93 } models[] = {
  94         { '1', "WR850G", 0x10577050LU },
  95         { '2', "WA840G", 0x10577040LU },
  96         { '3', "WE800G", 0x10577000LU },
  97         { '\0', NULL, 0 }
  98 };
  99
 100 static void usage(const char *) __attribute__ (( __noreturn__ ));
 101
 102 static void usage(const char *mess)
 103 {
 104         const struct model *m;
 105
 106         fprintf(stderr, "Error: %s\n", mess);
 107         fprintf(stderr, "Usage: motorola-bin -device|--strip infile outfile\n");
 108         fprintf(stderr, "Known devices: ");
 109
 110         for (m = models; m->digit != '\0'; m++)
 111                 fprintf(stderr, " %c - %s", m->digit, m->name);
 112
 113         fprintf(stderr, "\n");
 114         exit(1);
 115 }
 116
 117 int main(int argc, char **argv)
 118 {
 119         off_t len;      // of original firmware
 120         int fd;
 121         void *trx;      // pointer to original firmware (mmmapped)
 122         struct motorola *firmware;      // pionter to prefix + copy of original firmware
 123         uint32_t flags;
 124
 125         // verify parameters
 126
 127         if (argc != 4)
 128                 usage("wrong number of arguments");
 129
 130         // mmap trx file
 131         if ((fd = open(argv[2], O_RDONLY))  < 0
 132         || (len = lseek(fd, 0, SEEK_END)) < 0
 133         || (trx = mmap(0, len, PROT_READ, MAP_SHARED, fd, 0)) == (void *) (-1)
 134         || close(fd) < 0)
 135         {
 136                 fprintf(stderr, "Error loading file %s: %s\n", argv[2], strerror(errno));
 137                 exit(1);
 138         }
 139
 140         init_crc32();
 141
 142         if (strcmp(argv[1], "--strip") == 0)
 143         {
 144                 const char *ugh = NULL;
 145
 146                 if (len < sizeof(struct motorola)) {
 147                         ugh = "input file too short";
 148                 } else {
 149                         const struct model *m;
 150
 151                         firmware = trx;
 152                         if (htonl(crc32buf(trx + offsetof(struct motorola, flags), len - offsetof(struct motorola, flags))) != firmware->crc)
 153                                 ugh = "Invalid CRC";
 154                         for (m = models; ; m++) {
 155                                 if (m->digit == '\0') {
 156                                         if (ugh == NULL)
 157                                                 ugh = "unrecognized flags field";
 158                                         break;
 159                                 }
 160                                 if (firmware->flags == htonl(m->flags)) {
 161                                         fprintf(stderr, "Firmware for Motorola %s\n", m->name);
 162                                         break;
 163                                 }
 164                         }
 165                 }
 166
 167                 if (ugh != NULL) {
 168                         fprintf(stderr, "%s\n", ugh);
 169                         exit(3);
 170                 } else {
 171                         // all is well, write the file without the prefix
 172                         if ((fd = open(argv[3], O_CREAT|O_WRONLY|O_TRUNC,0644)) < 0
 173                         || write(fd, trx + sizeof(struct motorola), len - sizeof(struct motorola)) !=  len - sizeof(struct motorola)
 174                         || close(fd) < 0)
 175                         {
 176                                 fprintf(stderr, "Error storing file %s: %s\n", argv[3], strerror(errno));
 177                                 exit(2);
 178                         }
 179                 }
 180
 181         } else {
 182                 // setup the firmware flags magic number
 183                 const struct model *m;
 184                 const char *df = argv[1];
 185
 186                 if (*df != '-')
 187                         usage("first argument must start with -");
 188                 if (*++df == '-')
 189                         ++df;   /* allow but don't require second - */
 190
 191                 for (m = models; ; m++) {
 192                         if (m->digit == '\0')
 193                                 usage("unrecognized device specified");
 194                         if ((df[0] == m->digit && df[1] == '\0') || strcasecmp(df, m->name) == 0) {
 195                                 flags = m->flags;
 196                                 break;
 197                         }
 198                 }
 199
 200
 201                 // create a firmware image in memory
 202                 // and copy the trx to it
 203                 firmware = malloc(sizeof(struct motorola) + len);
 204                 memcpy(&firmware[1], trx, len);
 205
 206                 // setup the motorola headers
 207                 firmware->flags = htonl(flags);
 208
 209                 // CRC of flags + firmware
 210                 firmware->crc = htonl(crc32buf((unsigned char *)&firmware->flags, sizeof(firmware->flags) + len));
 211
 212                 // write the firmware
 213                 if ((fd = open(argv[3], O_CREAT|O_WRONLY|O_TRUNC,0644)) < 0
 214                 || write(fd, firmware, sizeof(struct motorola) + len) != sizeof(struct motorola) + len
 215                 || close(fd) < 0)
 216                 {
 217                         fprintf(stderr, "Error storing file %s: %s\n", argv[3], strerror(errno));
 218                         exit(2);
 219                 }
 220
 221                 free(firmware);
 222         }
 223
 224         munmap(trx,len);
 225
 226         return 0;
 227 }