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                 char    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
 106         fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
 107         fprintf(stream, "\n"
 108                         "Options:\n"
 109                         "  -f <file>            generate a factory flash image <file>\n"
 110                         "  -s <file>            generate a sysupgrade flash image <file>\n"
 111                         "  -h                   show this screen\n");
 112         exit(status);
 113 }
 114
 115 int
 116 process_image(char *progname, char *filename, op_mode_t opmode)
 117 {
 118         int             fd;
 119         void            *ptr;
 120         char            namebuf[IH_NMLEN];
 121         struct          stat sbuf;
 122         uint32_t        offset_kernel, offset_sqfs, offset_end,
 123                         offset_sec_header, offset_eb, offset_image_end;
 124         squashfs_sb_t *sqs;
 125         image_header_t *hdr;
 126
 127         if ((fd = open(filename, O_RDWR, 0666)) < 0) {
 128                 fprintf (stderr, "%s: Can't open %s: %s\n",
 129                         progname, filename, strerror(errno));
 130                 return (EXIT_FAILURE);
 131         }
 132
 133         if (fstat(fd, &sbuf) < 0) {
 134                 fprintf (stderr, "%s: Can't stat %s: %s\n",
 135                         progname, filename, strerror(errno));
 136                 return (EXIT_FAILURE);
 137         }
 138
 139         if ((unsigned)sbuf.st_size < sizeof(image_header_t)) {
 140                 fprintf (stderr,
 141                         "%s: Bad size: \"%s\" is no valid image\n",
 142                         progname, filename);
 143                 return (EXIT_FAILURE);
 144         }
 145
 146         ptr = (void *)mmap(0, sbuf.st_size,
 147                                 PROT_READ | PROT_WRITE,
 148                                 MAP_SHARED,
 149                                 fd, 0);
 150
 151         if ((caddr_t)ptr == (caddr_t)-1) {
 152                 fprintf (stderr, "%s: Can't read %s: %s\n",
 153                         progname, filename, strerror(errno));
 154                 return (EXIT_FAILURE);
 155         }
 156
 157         hdr = ptr;
 158
 159         if (ntohl(hdr->ih_magic) != IH_MAGIC) {
 160                 fprintf (stderr,
 161                         "%s: Bad Magic Number: \"%s\" is no valid image\n",
 162                         progname, filename);
 163                 return (EXIT_FAILURE);
 164         }
 165
 166         if (opmode == FACTORY) {
 167                 strncpy(namebuf, hdr->tail.ih_name, IH_NMLEN);
 168                 hdr->tail.asus.kernel.major = 0;
 169                 hdr->tail.asus.kernel.minor = 0;
 170                 hdr->tail.asus.fs.major = 0;
 171                 hdr->tail.asus.fs.minor = 0;
 172                 strncpy((char *)&hdr->tail.asus.productid, "RT-N56U", IH_PRODLEN);
 173         }
 174
 175         if (hdr->tail.asus.ih_ksz == 0)
 176                 hdr->tail.asus.ih_ksz = htonl(ntohl(hdr->ih_size) + sizeof(image_header_t));
 177
 178         offset_kernel = sizeof(image_header_t);
 179         offset_sqfs = ntohl(hdr->tail.asus.ih_ksz);
 180         sqs = ptr + offset_sqfs;
 181         offset_sec_header = offset_sqfs + sqs->bytes_used;
 182
 183         /*
 184          * Reserve space for the second header.
 185          */
 186         offset_end = offset_sec_header + sizeof(image_header_t);
 187         offset_eb = ((offset_end>>16)+1)<<16;
 188
 189         if (opmode == FACTORY)
 190                 offset_image_end = offset_eb + 4;
 191         else
 192                 offset_image_end = sbuf.st_size;
 193         /*
 194          * Move the second header at the end of the image.
 195          */
 196         offset_end = offset_sec_header;
 197         offset_sec_header = offset_eb - sizeof(image_header_t);
 198
 199         /*
 200          * Remove jffs2 markers between squashfs and eb boundary.
 201          */
 202         if (opmode == FACTORY)
 203                 memset(ptr+offset_end, 0xff ,offset_eb - offset_end);
 204
 205         /*
 206          * Grow the image if needed.
 207          */
 208         if (offset_image_end > sbuf.st_size) {
 209                 (void) munmap((void *)ptr, sbuf.st_size);
 210                 ftruncate(fd, offset_image_end);
 211                 ptr = (void *)mmap(0, offset_image_end,
 212                                                 PROT_READ | PROT_WRITE,
 213                                                 MAP_SHARED,
 214                                                 fd, 0);
 215                 /*
 216                  * jffs2 marker
 217                  */
 218                 if (opmode == FACTORY) {
 219                         *(uint8_t *)(ptr+offset_image_end-4) = 0xde;
 220                         *(uint8_t *)(ptr+offset_image_end-3) = 0xad;
 221                         *(uint8_t *)(ptr+offset_image_end-2) = 0xc0;
 222                         *(uint8_t *)(ptr+offset_image_end-1) = 0xde;
 223                 }
 224         }
 225
 226         /*
 227          * Calculate checksums for the second header to be used after flashing.
 228          */
 229         if (opmode == FACTORY) {
 230                 hdr = ptr+offset_sec_header;
 231                 memcpy(hdr, ptr, sizeof(image_header_t));
 232                 strncpy(hdr->tail.ih_name, namebuf, IH_NMLEN);
 233                 calc_crc(hdr, ptr+offset_kernel, offset_sqfs - offset_kernel);
 234                 calc_crc((image_header_t *)ptr, ptr+offset_kernel, offset_image_end - offset_kernel);
 235         } else {
 236                 calc_crc((image_header_t *)ptr, ptr+offset_kernel, offset_sqfs - offset_kernel);
 237         }
 238
 239         if (sbuf.st_size > offset_image_end)
 240                 (void) munmap((void *)ptr, sbuf.st_size);
 241         else
 242                 (void) munmap((void *)ptr, offset_image_end);
 243
 244         ftruncate(fd, offset_image_end);
 245         (void) close (fd);
 246
 247         return EXIT_SUCCESS;
 248 }
 249
 250 int
 251 main(int argc, char **argv)
 252 {
 253         int             opt;
 254         char            *filename = NULL;
 255         char            *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