tools/firmware-utils/src/mkrtn56uimg.c

   1 /*
   2  *
   3  *  Copyright (C) 2014 OpenWrt.org
   4  *  Copyright (C) 2014 Mikko Hissa <mikko.hissa@werzek.com>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify it
   7  *  under the terms of the GNU General Public License version 2 as published
   8  *  by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <errno.h>
  13 #include <fcntl.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <netinet/in.h>
  18 #include <sys/mman.h>
  19 #include <sys/stat.h>
  20 #include <unistd.h>
  21 #include <zlib.h>
  22
  23 #define IH_MAGIC        0x27051956
  24 #define IH_NMLEN        32
  25 #define IH_PRODLEN      23
  26
  27 #define IH_TYPE_INVALID         0
  28 #define IH_TYPE_STANDALONE      1
  29 #define IH_TYPE_KERNEL          2
  30 #define IH_TYPE_RAMDISK         3
  31 #define IH_TYPE_MULTI           4
  32 #define IH_TYPE_FIRMWARE        5
  33 #define IH_TYPE_SCRIPT          6
  34 #define IH_TYPE_FILESYSTEM      7
  35
  36 /*
  37  * Compression Types
  38  */
  39 #define IH_COMP_NONE            0
  40 #define IH_COMP_GZIP            1
  41 #define IH_COMP_BZIP2           2
  42 #define IH_COMP_LZMA            3
  43
  44 typedef struct {
  45         uint8_t major;
  46         uint8_t minor;
  47 } version_t;
  48
  49 typedef struct {
  50         version_t       kernel;
  51         version_t       fs;
  52         uint8_t         productid[IH_PRODLEN];
  53         uint8_t         sub_fs;
  54         uint32_t        ih_ksz;
  55 } asus_t;
  56
  57 typedef struct image_header {
  58         uint32_t        ih_magic;
  59         uint32_t        ih_hcrc;
  60         uint32_t        ih_time;
  61         uint32_t        ih_size;
  62         uint32_t        ih_load;
  63         uint32_t        ih_ep;
  64         uint32_t        ih_dcrc;
  65         uint8_t         ih_os;
  66         uint8_t         ih_arch;
  67         uint8_t         ih_type;
  68         uint8_t         ih_comp;
  69         union {
  70                 uint8_t ih_name[IH_NMLEN];
  71                 asus_t  asus;
  72         } tail;
  73 } image_header_t;
  74
  75 typedef struct squashfs_sb {
  76         uint32_t        s_magic;
  77         uint32_t        pad0[9];
  78         uint64_t        bytes_used;
  79 } squashfs_sb_t;
  80
  81 typedef enum {
  82         NONE, FACTORY, SYSUPGRADE,
  83 } op_mode_t;
  84
  85 void
  86 calc_crc(image_header_t *hdr, void *data, uint32_t len)
  87 {
  88         /*
  89          * Calculate payload checksum
  90          */
  91         hdr->ih_dcrc = htonl(crc32(0, (Bytef *)data, len));
  92         hdr->ih_size = htonl(len);
  93         /*
  94          * Calculate header checksum
  95          */
  96         hdr->ih_hcrc = 0;
  97         hdr->ih_hcrc = htonl(crc32(0, (Bytef *)hdr, sizeof(image_header_t)));
  98 }
  99
 100
 101 static void
 102 usage(const char *progname, int status)
 103 {
 104         FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout;
 105         int i;
 106
 107         fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
 108         fprintf(stream, "\n"
 109                         "Options:\n"
 110                         "  -f <file>            generate a factory flash image <file>\n"
 111                         "  -s <file>            generate a sysupgrade flash image <file>\n"
 112                         "  -h                   show this screen\n");
 113         exit(status);
 114 }
 115
 116 int
 117 process_image(char *progname, char *filename, op_mode_t opmode)
 118 {
 119         int             fd, len;
 120         void            *data, *ptr;
 121         char            namebuf[IH_NMLEN];
 122         struct          stat sbuf;
 123         uint32_t        checksum, offset_kernel, offset_sqfs, offset_end,
 124                                 offset_sec_header, offset_eb, offset_image_end;
 125         squashfs_sb_t *sqs;
 126         image_header_t *hdr;
 127
 128         if ((fd = open(filename, O_RDWR, 0666)) < 0) {
 129                 fprintf (stderr, "%s: Can't open %s: %s\n",
 130                         progname, filename, strerror(errno));
 131                 return (EXIT_FAILURE);
 132         }
 133
 134         if (fstat(fd, &sbuf) < 0) {
 135                 fprintf (stderr, "%s: Can't stat %s: %s\n",
 136                         progname, filename, strerror(errno));
 137                 return (EXIT_FAILURE);
 138         }
 139
 140         if ((unsigned)sbuf.st_size < sizeof(image_header_t)) {
 141                 fprintf (stderr,
 142                         "%s: Bad size: \"%s\" is no valid image\n",
 143                         progname, filename);
 144                 return (EXIT_FAILURE);
 145         }
 146
 147         ptr = (void *)mmap(0, sbuf.st_size,
 148                                 PROT_READ | PROT_WRITE,
 149                                 MAP_SHARED,
 150                                 fd, 0);
 151
 152         if ((caddr_t)ptr == (caddr_t)-1) {
 153                 fprintf (stderr, "%s: Can't read %s: %s\n",
 154                         progname, filename, strerror(errno));
 155                 return (EXIT_FAILURE);
 156         }
 157
 158         hdr = ptr;
 159
 160         if (ntohl(hdr->ih_magic) != IH_MAGIC) {
 161                 fprintf (stderr,
 162                         "%s: Bad Magic Number: \"%s\" is no valid image\n",
 163                         progname, filename);
 164                 return (EXIT_FAILURE);
 165         }
 166
 167         if (opmode == FACTORY) {
 168                 strncpy(namebuf, hdr->tail.ih_name, IH_NMLEN);
 169                 hdr->tail.asus.kernel.major = 0;
 170                 hdr->tail.asus.kernel.minor = 0;
 171                 hdr->tail.asus.fs.major = 0;
 172                 hdr->tail.asus.fs.minor = 0;
 173                 strncpy((char *)&hdr->tail.asus.productid, "RT-N56U", IH_PRODLEN);
 174         }
 175
 176         if (hdr->tail.asus.ih_ksz == 0)
 177                 hdr->tail.asus.ih_ksz = htonl(ntohl(hdr->ih_size) + sizeof(image_header_t));
 178
 179         offset_kernel = sizeof(image_header_t);
 180         offset_sqfs = ntohl(hdr->tail.asus.ih_ksz);
 181         sqs = ptr + offset_sqfs;
 182         offset_sec_header = offset_sqfs + sqs->bytes_used;
 183
 184         /*
 185          * Reserve space for the second header.
 186          */
 187         offset_end = offset_sec_header + sizeof(image_header_t);
 188         offset_eb = ((offset_end>>16)+1)<<16;
 189
 190         if (opmode == FACTORY)
 191                 offset_image_end = offset_eb + 4;
 192         else
 193                 offset_image_end = sbuf.st_size;
 194         /*
 195          * Move the second header at the end of the image.
 196          */
 197         offset_end = offset_sec_header;
 198         offset_sec_header = offset_eb - sizeof(image_header_t);
 199
 200         /*
 201          * Remove jffs2 markers between squashfs and eb boundary.
 202          */
 203         if (opmode == FACTORY)
 204                 memset(ptr+offset_end, 0xff ,offset_eb - offset_end);
 205
 206         /*
 207          * Grow the image if needed.
 208          */
 209         if (offset_image_end > sbuf.st_size) {
 210                 (void) munmap((void *)ptr, sbuf.st_size);
 211                 ftruncate(fd, offset_image_end);
 212                 ptr = (void *)mmap(0, offset_image_end,
 213                                                 PROT_READ | PROT_WRITE,
 214                                                 MAP_SHARED,
 215                                                 fd, 0);
 216                 /*
 217                  * jffs2 marker
 218                  */
 219                 if (opmode == FACTORY) {
 220                         *(uint8_t *)(ptr+offset_image_end-4) = 0xde;
 221                         *(uint8_t *)(ptr+offset_image_end-3) = 0xad;
 222                         *(uint8_t *)(ptr+offset_image_end-2) = 0xc0;
 223                         *(uint8_t *)(ptr+offset_image_end-1) = 0xde;
 224                 }
 225         }
 226
 227         /*
 228          * Calculate checksums for the second header to be used after flashing.
 229          */
 230         if (opmode == FACTORY) {
 231                 hdr = ptr+offset_sec_header;
 232                 memcpy(hdr, ptr, sizeof(image_header_t));
 233                 strncpy(hdr->tail.ih_name, namebuf, IH_NMLEN);
 234                 calc_crc(hdr, ptr+offset_kernel, offset_sqfs - offset_kernel);
 235                 calc_crc((image_header_t *)ptr, ptr+offset_kernel, offset_image_end - offset_kernel);
 236         } else {
 237                 calc_crc((image_header_t *)ptr, ptr+offset_kernel, offset_sqfs - offset_kernel);
 238         }
 239
 240         if (sbuf.st_size > offset_image_end)
 241                 (void) munmap((void *)ptr, sbuf.st_size);
 242         else
 243                 (void) munmap((void *)ptr, offset_image_end);
 244
 245         ftruncate(fd, offset_image_end);
 246         (void) close (fd);
 247
 248         return EXIT_SUCCESS;
 249 }
 250
 251 int
 252 main(int argc, char **argv)
 253 {
 254         int             opt;
 255         char            *filename, *progname;
 256         op_mode_t       opmode = NONE;
 257
 258         progname = argv[0];
 259
 260         while ((opt = getopt(argc, argv,":s:f:h?")) != -1) {
 261                 switch (opt) {
 262                 case 's':
 263                         opmode = SYSUPGRADE;
 264                         filename = optarg;
 265                         break;
 266                 case 'f':
 267                         opmode = FACTORY;
 268                         filename = optarg;
 269                         break;
 270                 case 'h':
 271                         opmode = NONE;
 272                 default:
 273                         usage(progname, EXIT_FAILURE);
 274                         opmode = NONE;
 275                 }
 276         }
 277
 278         if(filename == NULL)
 279                 opmode = NONE;
 280
 281         switch (opmode) {
 282         case NONE:
 283                 usage(progname, EXIT_FAILURE);
 284                 break;
 285         case FACTORY:
 286         case SYSUPGRADE:
 287                 return process_image(progname, filename, opmode);
 288                 break;
 289         }
 290
 291         return EXIT_SUCCESS;
 292 }
 293