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  * $Id$
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  24  *
  25  */
  26
  27 /*
  28  * Motorola's firmware flashing code requires an extra header.
  29  * The header is eight bytes (see struct motorola below).
  30  * This program will take a firmware file and create a new one
  31  * with this header:
  32  *      motorola-bin --wr850g WR850G_V403.stripped.trx WR850G_V403.trx
  33  *
  34  * Note: Motorola's firmware is distributed with this header.
  35  * If you need to flash Motorola firmware on a router running OpenWRT,
  36  * you will to remove this header.  Use the --strip flag:
  37  *      motorola-bin --strip WR850G_V403.trx WR850G_V403.stripped.trx
  38  */
  39
  40 /*
  41  * February 1, 2006
  42  *
  43  * Add support for for creating WA840G and WE800G images
  44  */
  45
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <stddef.h>
  49 #include <unistd.h>
  50 #include <errno.h>
  51 #include <fcntl.h>
  52 #include <sys/mman.h>
  53 #include <string.h>
  54 #include <netinet/in.h>
  55 #include <inttypes.h>
  56
  57 #define BPB 8 /* bits/byte */
  58
  59 static uint32_t crc32[1<<BPB];
  60
  61 static void init_crc32()
  62 {
  63         const uint32_t poly = ntohl(0x2083b8ed);
  64         int n;
  65
  66         for (n = 0; n < 1<<BPB; n++) {
  67                 uint32_t crc = n;
  68                 int bit;
  69
  70                 for (bit = 0; bit < BPB; bit++)
  71                         crc = (crc & 1) ? (poly ^ (crc >> 1)) : (crc >> 1);
  72                 crc32[n] = crc;
  73         }
  74 }
  75
  76 static uint32_t crc32buf(unsigned char *buf, size_t len)
  77 {
  78         uint32_t crc = 0xFFFFFFFF;
  79
  80         for (; len; len--, buf++)
  81                 crc = crc32[(uint8_t)crc ^ *buf] ^ (crc >> BPB);
  82         return crc;
  83 }
  84
  85 struct motorola {
  86         uint32_t crc;   // crc32 of the remainder
  87         uint32_t flags; // unknown, 105770*
  88 };
  89
  90 static const struct model {
  91         char digit;     /* a digit signifying model (historical) */
  92         const char *name;
  93         uint32_t flags;
  94 } models[] = {
  95         { '1', "WR850G", 0x10577050LU },
  96         { '2', "WA840G", 0x10577040LU },
  97         { '3', "WE800G", 0x10577000LU },
  98         { '\0', NULL, 0 }
  99 };
 100
 101 static void usage(const char *) __attribute__ (( __noreturn__ ));
 102
 103 static void usage(const char *mess)
 104 {
 105         const struct model *m;
 106
 107         fprintf(stderr, "Error: %s\n", mess);
 108         fprintf(stderr, "Usage: motorola-bin -device|--strip infile outfile\n");
 109         fprintf(stderr, "Known devices: ");
 110
 111         for (m = models; m->digit != '\0'; m++)
 112                 fprintf(stderr, " %c - %s", m->digit, m->name);
 113
 114         fprintf(stderr, "\n");
 115         exit(1);
 116 }
 117
 118 int main(int argc, char **argv)
 119 {
 120         off_t len;      // of original firmware
 121         int fd;
 122         void *trx;      // pointer to original firmware (mmmapped)
 123         struct motorola *firmware;      // pionter to prefix + copy of original firmware
 124         uint32_t flags;
 125
 126         // verify parameters
 127
 128         if (argc != 4)
 129                 usage("wrong number of arguments");
 130
 131         // mmap trx file
 132         if ((fd = open(argv[2], O_RDONLY))  < 0
 133         || (len = lseek(fd, 0, SEEK_END)) < 0
 134         || (trx = mmap(0, len, PROT_READ, MAP_SHARED, fd, 0)) == (void *) (-1)
 135         || close(fd) < 0)
 136         {
 137                 fprintf(stderr, "Error loading file %s: %s\n", argv[2], strerror(errno));
 138                 exit(1);
 139         }
 140
 141         init_crc32();
 142
 143         if (strcmp(argv[1], "--strip") == 0)
 144         {
 145                 const char *ugh = NULL;
 146
 147                 if (len < sizeof(struct motorola)) {
 148                         ugh = "input file too short";
 149                 } else {
 150                         const struct model *m;
 151
 152                         firmware = trx;
 153                         if (htonl(crc32buf(trx + offsetof(struct motorola, flags), len - offsetof(struct motorola, flags))) != firmware->crc)
 154                                 ugh = "Invalid CRC";
 155                         for (m = models; ; m++) {
 156                                 if (m->digit == '\0') {
 157                                         if (ugh == NULL)
 158                                                 ugh = "unrecognized flags field";
 159                                         break;
 160                                 }
 161                                 if (firmware->flags == htonl(m->flags)) {
 162                                         fprintf(stderr, "Firmware for Motorola %s\n", m->name);
 163                                         break;
 164                                 }
 165                         }
 166                 }
 167
 168                 if (ugh != NULL) {
 169                         fprintf(stderr, "%s\n", ugh);
 170                         exit(3);
 171                 } else {
 172                         // all is well, write the file without the prefix
 173                         if ((fd = open(argv[3], O_CREAT|O_WRONLY,0644)) < 0
 174                         || write(fd, trx + sizeof(struct motorola), len - sizeof(struct motorola)) !=  len - sizeof(struct motorola)
 175                         || close(fd) < 0)
 176                         {
 177                                 fprintf(stderr, "Error storing file %s: %s\n", argv[3], strerror(errno));
 178                                 exit(2);
 179                         }
 180                 }
 181
 182         } else {
 183                 // setup the firmware flags magic number
 184                 const struct model *m;
 185                 const char *df = argv[1];
 186
 187                 if (*df != '-')
 188                         usage("first argument must start with -");
 189                 if (*++df == '-')
 190                         ++df;   /* allow but don't require second - */
 191
 192                 for (m = models; ; m++) {
 193                         if (m->digit == '\0')
 194                                 usage("unrecognized device specified");
 195                         if ((df[0] == m->digit && df[1] == '\0') || strcasecmp(df, m->name) == 0) {
 196                                 flags = m->flags;
 197                                 break;
 198                         }
 199                 }
 200
 201
 202                 // create a firmware image in memory
 203                 // and copy the trx to it
 204                 firmware = malloc(sizeof(struct motorola) + len);
 205                 memcpy(&firmware[1], trx, len);
 206
 207                 // setup the motorola headers
 208                 firmware->flags = htonl(flags);
 209
 210                 // CRC of flags + firmware
 211                 firmware->crc = htonl(crc32buf((unsigned char *)&firmware->flags, sizeof(firmware->flags) + len));
 212
 213                 // write the firmware
 214                 if ((fd = open(argv[3], O_CREAT|O_WRONLY,0644)) < 0
 215                 || write(fd, firmware, sizeof(struct motorola) + len) != sizeof(struct motorola) + len
 216                 || close(fd) < 0)
 217                 {
 218                         fprintf(stderr, "Error storing file %s: %s\n", argv[3], strerror(errno));
 219                         exit(2);
 220                 }
 221
 222                 free(firmware);
 223         }
 224
 225         munmap(trx,len);
 226
 227         return 0;
 228 }