target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_uimage.c

   1 /*
   2  *  Copyright (C) 2013 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 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/vmalloc.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/partitions.h>
  19 #include <linux/version.h>
  20 #include <linux/byteorder/generic.h>
  21 #include <linux/of.h>
  22
  23 #include "mtdsplit.h"
  24
  25 /*
  26  * uimage_header itself is only 64B, but it may be prepended with another data.
  27  * Currently the biggest size is for Fon(Foxconn) devices: 64B + 32B
  28  */
  29 #define MAX_HEADER_LEN          96
  30
  31 #define IH_MAGIC        0x27051956      /* Image Magic Number           */
  32 #define IH_NMLEN                32      /* Image Name Length            */
  33
  34 #define IH_OS_LINUX             5       /* Linux        */
  35
  36 #define IH_TYPE_KERNEL          2       /* OS Kernel Image              */
  37 #define IH_TYPE_FILESYSTEM      7       /* Filesystem Image             */
  38
  39 /*
  40  * Legacy format image header,
  41  * all data in network byte order (aka natural aka bigendian).
  42  */
  43 struct uimage_header {
  44         uint32_t        ih_magic;       /* Image Header Magic Number    */
  45         uint32_t        ih_hcrc;        /* Image Header CRC Checksum    */
  46         uint32_t        ih_time;        /* Image Creation Timestamp     */
  47         uint32_t        ih_size;        /* Image Data Size              */
  48         uint32_t        ih_load;        /* Data  Load  Address          */
  49         uint32_t        ih_ep;          /* Entry Point Address          */
  50         uint32_t        ih_dcrc;        /* Image Data CRC Checksum      */
  51         uint8_t         ih_os;          /* Operating System             */
  52         uint8_t         ih_arch;        /* CPU architecture             */
  53         uint8_t         ih_type;        /* Image Type                   */
  54         uint8_t         ih_comp;        /* Compression Type             */
  55         uint8_t         ih_name[IH_NMLEN];      /* Image Name           */
  56 };
  57
  58 static int
  59 read_uimage_header(struct mtd_info *mtd, size_t offset, u_char *buf,
  60                    size_t header_len)
  61 {
  62         size_t retlen;
  63         int ret;
  64
  65         ret = mtd_read(mtd, offset, header_len, &retlen, buf);
  66         if (ret) {
  67                 pr_debug("read error in \"%s\"\n", mtd->name);
  68                 return ret;
  69         }
  70
  71         if (retlen != header_len) {
  72                 pr_debug("short read in \"%s\"\n", mtd->name);
  73                 return -EIO;
  74         }
  75
  76         return 0;
  77 }
  78
  79 /**
  80  * __mtdsplit_parse_uimage - scan partition and create kernel + rootfs parts
  81  *
  82  * @find_header: function to call for a block of data that will return offset
  83  *      and tail padding length of a valid uImage header if found
  84  */
  85 static int __mtdsplit_parse_uimage(struct mtd_info *master,
  86                    const struct mtd_partition **pparts,
  87                    struct mtd_part_parser_data *data,
  88                    ssize_t (*find_header)(u_char *buf, size_t len, int *extralen))
  89 {
  90         struct mtd_partition *parts;
  91         u_char *buf;
  92         int nr_parts;
  93         size_t offset;
  94         size_t uimage_offset;
  95         size_t uimage_size = 0;
  96         size_t rootfs_offset;
  97         size_t rootfs_size = 0;
  98         int uimage_part, rf_part;
  99         int ret;
 100         int extralen;
 101         enum mtdsplit_part_type type;
 102
 103         nr_parts = 2;
 104         parts = kzalloc(nr_parts * sizeof(*parts), GFP_KERNEL);
 105         if (!parts)
 106                 return -ENOMEM;
 107
 108         buf = vmalloc(MAX_HEADER_LEN);
 109         if (!buf) {
 110                 ret = -ENOMEM;
 111                 goto err_free_parts;
 112         }
 113
 114         /* find uImage on erase block boundaries */
 115         for (offset = 0; offset < master->size; offset += master->erasesize) {
 116                 struct uimage_header *header;
 117
 118                 uimage_size = 0;
 119
 120                 ret = read_uimage_header(master, offset, buf, MAX_HEADER_LEN);
 121                 if (ret)
 122                         continue;
 123
 124                 extralen = 0;
 125                 ret = find_header(buf, MAX_HEADER_LEN, &extralen);
 126                 if (ret < 0) {
 127                         pr_debug("no valid uImage found in \"%s\" at offset %llx\n",
 128                                  master->name, (unsigned long long) offset);
 129                         continue;
 130                 }
 131                 header = (struct uimage_header *)(buf + ret);
 132
 133                 uimage_size = sizeof(*header) +
 134                                 be32_to_cpu(header->ih_size) + ret + extralen;
 135
 136                 if ((offset + uimage_size) > master->size) {
 137                         pr_debug("uImage exceeds MTD device \"%s\"\n",
 138                                  master->name);
 139                         continue;
 140                 }
 141                 break;
 142         }
 143
 144         if (uimage_size == 0) {
 145                 pr_debug("no uImage found in \"%s\"\n", master->name);
 146                 ret = -ENODEV;
 147                 goto err_free_buf;
 148         }
 149
 150         uimage_offset = offset;
 151
 152         if (uimage_offset == 0) {
 153                 uimage_part = 0;
 154                 rf_part = 1;
 155
 156                 /* find the roots after the uImage */
 157                 ret = mtd_find_rootfs_from(master, uimage_offset + uimage_size,
 158                                            master->size, &rootfs_offset, &type);
 159                 if (ret) {
 160                         pr_debug("no rootfs after uImage in \"%s\"\n",
 161                                  master->name);
 162                         goto err_free_buf;
 163                 }
 164
 165                 rootfs_size = master->size - rootfs_offset;
 166                 uimage_size = rootfs_offset - uimage_offset;
 167         } else {
 168                 rf_part = 0;
 169                 uimage_part = 1;
 170
 171                 /* check rootfs presence at offset 0 */
 172                 ret = mtd_check_rootfs_magic(master, 0, &type);
 173                 if (ret) {
 174                         pr_debug("no rootfs before uImage in \"%s\"\n",
 175                                  master->name);
 176                         goto err_free_buf;
 177                 }
 178
 179                 rootfs_offset = 0;
 180                 rootfs_size = uimage_offset;
 181         }
 182
 183         if (rootfs_size == 0) {
 184                 pr_debug("no rootfs found in \"%s\"\n", master->name);
 185                 ret = -ENODEV;
 186                 goto err_free_buf;
 187         }
 188
 189         parts[uimage_part].name = KERNEL_PART_NAME;
 190         parts[uimage_part].offset = uimage_offset;
 191         parts[uimage_part].size = uimage_size;
 192
 193         if (type == MTDSPLIT_PART_TYPE_UBI)
 194                 parts[rf_part].name = UBI_PART_NAME;
 195         else
 196                 parts[rf_part].name = ROOTFS_PART_NAME;
 197         parts[rf_part].offset = rootfs_offset;
 198         parts[rf_part].size = rootfs_size;
 199
 200         vfree(buf);
 201
 202         *pparts = parts;
 203         return nr_parts;
 204
 205 err_free_buf:
 206         vfree(buf);
 207
 208 err_free_parts:
 209         kfree(parts);
 210         return ret;
 211 }
 212
 213 static ssize_t uimage_verify_default(u_char *buf, size_t len, int *extralen)
 214 {
 215         struct uimage_header *header = (struct uimage_header *)buf;
 216
 217         /* default sanity checks */
 218         if (be32_to_cpu(header->ih_magic) != IH_MAGIC) {
 219                 pr_debug("invalid uImage magic: %08x\n",
 220                          be32_to_cpu(header->ih_magic));
 221                 return -EINVAL;
 222         }
 223
 224         if (header->ih_os != IH_OS_LINUX) {
 225                 pr_debug("invalid uImage OS: %08x\n",
 226                          be32_to_cpu(header->ih_os));
 227                 return -EINVAL;
 228         }
 229
 230         if (header->ih_type != IH_TYPE_KERNEL) {
 231                 pr_debug("invalid uImage type: %08x\n",
 232                          be32_to_cpu(header->ih_type));
 233                 return -EINVAL;
 234         }
 235
 236         return 0;
 237 }
 238
 239 static int
 240 mtdsplit_uimage_parse_generic(struct mtd_info *master,
 241                               const struct mtd_partition **pparts,
 242                               struct mtd_part_parser_data *data)
 243 {
 244         return __mtdsplit_parse_uimage(master, pparts, data,
 245                                       uimage_verify_default);
 246 }
 247
 248 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 249 static const struct of_device_id mtdsplit_uimage_of_match_table[] = {
 250         { .compatible = "denx,uimage" },
 251         {},
 252 };
 253 #endif
 254
 255 static struct mtd_part_parser uimage_generic_parser = {
 256         .owner = THIS_MODULE,
 257         .name = "uimage-fw",
 258 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 259         .of_match_table = mtdsplit_uimage_of_match_table,
 260 #endif
 261         .parse_fn = mtdsplit_uimage_parse_generic,
 262         .type = MTD_PARSER_TYPE_FIRMWARE,
 263 };
 264
 265 #define FW_MAGIC_WNR2000V1      0x32303031
 266 #define FW_MAGIC_WNR2000V3      0x32303033
 267 #define FW_MAGIC_WNR2000V4      0x32303034
 268 #define FW_MAGIC_WNR2200        0x32323030
 269 #define FW_MAGIC_WNR612V2       0x32303631
 270 #define FW_MAGIC_WNR1000V2      0x31303031
 271 #define FW_MAGIC_WNR1000V2_VC   0x31303030
 272 #define FW_MAGIC_WNDR3700       0x33373030
 273 #define FW_MAGIC_WNDR3700V2     0x33373031
 274 #define FW_MAGIC_WPN824N        0x31313030
 275
 276 static ssize_t uimage_verify_wndr3700(u_char *buf, size_t len, int *extralen)
 277 {
 278         struct uimage_header *header = (struct uimage_header *)buf;
 279         uint8_t expected_type = IH_TYPE_FILESYSTEM;
 280
 281         switch (be32_to_cpu(header->ih_magic)) {
 282         case FW_MAGIC_WNR612V2:
 283         case FW_MAGIC_WNR1000V2:
 284         case FW_MAGIC_WNR1000V2_VC:
 285         case FW_MAGIC_WNR2000V1:
 286         case FW_MAGIC_WNR2000V3:
 287         case FW_MAGIC_WNR2200:
 288         case FW_MAGIC_WNDR3700:
 289         case FW_MAGIC_WNDR3700V2:
 290         case FW_MAGIC_WPN824N:
 291                 break;
 292         case FW_MAGIC_WNR2000V4:
 293                 expected_type = IH_TYPE_KERNEL;
 294                 break;
 295         default:
 296                 return -EINVAL;
 297         }
 298
 299         if (header->ih_os != IH_OS_LINUX ||
 300             header->ih_type != expected_type)
 301                 return -EINVAL;
 302
 303         return 0;
 304 }
 305
 306 static int
 307 mtdsplit_uimage_parse_netgear(struct mtd_info *master,
 308                               const struct mtd_partition **pparts,
 309                               struct mtd_part_parser_data *data)
 310 {
 311         return __mtdsplit_parse_uimage(master, pparts, data,
 312                                       uimage_verify_wndr3700);
 313 }
 314
 315 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 316 static const struct of_device_id mtdsplit_uimage_netgear_of_match_table[] = {
 317         { .compatible = "netgear,uimage" },
 318         {},
 319 };
 320 #endif
 321
 322 static struct mtd_part_parser uimage_netgear_parser = {
 323         .owner = THIS_MODULE,
 324         .name = "netgear-fw",
 325 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 326         .of_match_table = mtdsplit_uimage_netgear_of_match_table,
 327 #endif
 328         .parse_fn = mtdsplit_uimage_parse_netgear,
 329         .type = MTD_PARSER_TYPE_FIRMWARE,
 330 };
 331
 332 /**************************************************
 333  * Edimax
 334  **************************************************/
 335
 336 #define FW_EDIMAX_OFFSET        20
 337 #define FW_MAGIC_EDIMAX         0x43535953
 338
 339 static ssize_t uimage_find_edimax(u_char *buf, size_t len, int *extralen)
 340 {
 341         u32 *magic;
 342
 343         if (len < FW_EDIMAX_OFFSET + sizeof(struct uimage_header)) {
 344                 pr_err("Buffer too small for checking Edimax header\n");
 345                 return -ENOSPC;
 346         }
 347
 348         magic = (u32 *)buf;
 349         if (be32_to_cpu(*magic) != FW_MAGIC_EDIMAX)
 350                 return -EINVAL;
 351
 352         if (!uimage_verify_default(buf + FW_EDIMAX_OFFSET, len, extralen))
 353                 return FW_EDIMAX_OFFSET;
 354
 355         return -EINVAL;
 356 }
 357
 358 static int
 359 mtdsplit_uimage_parse_edimax(struct mtd_info *master,
 360                               const struct mtd_partition **pparts,
 361                               struct mtd_part_parser_data *data)
 362 {
 363         return __mtdsplit_parse_uimage(master, pparts, data,
 364                                        uimage_find_edimax);
 365 }
 366
 367 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 368 static const struct of_device_id mtdsplit_uimage_edimax_of_match_table[] = {
 369         { .compatible = "edimax,uimage" },
 370         {},
 371 };
 372 #endif
 373
 374 static struct mtd_part_parser uimage_edimax_parser = {
 375         .owner = THIS_MODULE,
 376         .name = "edimax-fw",
 377 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 378         .of_match_table = mtdsplit_uimage_edimax_of_match_table,
 379 #endif
 380         .parse_fn = mtdsplit_uimage_parse_edimax,
 381         .type = MTD_PARSER_TYPE_FIRMWARE,
 382 };
 383
 384
 385 /**************************************************
 386  * Fon(Foxconn)
 387  **************************************************/
 388
 389 #define FONFXC_PAD_LEN          32
 390
 391 static ssize_t uimage_find_fonfxc(u_char *buf, size_t len, int *extralen)
 392 {
 393         if (uimage_verify_default(buf, len, extralen) < 0)
 394                 return -EINVAL;
 395
 396         *extralen = FONFXC_PAD_LEN;
 397
 398         return 0;
 399 }
 400
 401 static int
 402 mtdsplit_uimage_parse_fonfxc(struct mtd_info *master,
 403                               const struct mtd_partition **pparts,
 404                               struct mtd_part_parser_data *data)
 405 {
 406         return __mtdsplit_parse_uimage(master, pparts, data,
 407                                        uimage_find_fonfxc);
 408 }
 409
 410 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 411 static const struct of_device_id mtdsplit_uimage_fonfxc_of_match_table[] = {
 412         { .compatible = "fonfxc,uimage" },
 413         {},
 414 };
 415 #endif
 416
 417 static struct mtd_part_parser uimage_fonfxc_parser = {
 418         .owner = THIS_MODULE,
 419         .name = "fonfxc-fw",
 420 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 421         .of_match_table = mtdsplit_uimage_fonfxc_of_match_table,
 422 #endif
 423         .parse_fn = mtdsplit_uimage_parse_fonfxc,
 424 };
 425
 426 /**************************************************
 427  * OKLI (OpenWrt Kernel Loader Image)
 428  **************************************************/
 429
 430 #define IH_MAGIC_OKLI   0x4f4b4c49
 431
 432 static ssize_t uimage_verify_okli(u_char *buf, size_t len, int *extralen)
 433 {
 434         struct uimage_header *header = (struct uimage_header *)buf;
 435
 436         /* default sanity checks */
 437         if (be32_to_cpu(header->ih_magic) != IH_MAGIC_OKLI) {
 438                 pr_debug("invalid uImage magic: %08x\n",
 439                          be32_to_cpu(header->ih_magic));
 440                 return -EINVAL;
 441         }
 442
 443         if (header->ih_os != IH_OS_LINUX) {
 444                 pr_debug("invalid uImage OS: %08x\n",
 445                          be32_to_cpu(header->ih_os));
 446                 return -EINVAL;
 447         }
 448
 449         if (header->ih_type != IH_TYPE_KERNEL) {
 450                 pr_debug("invalid uImage type: %08x\n",
 451                          be32_to_cpu(header->ih_type));
 452                 return -EINVAL;
 453         }
 454
 455         return 0;
 456 }
 457
 458 static int
 459 mtdsplit_uimage_parse_okli(struct mtd_info *master,
 460                               const struct mtd_partition **pparts,
 461                               struct mtd_part_parser_data *data)
 462 {
 463         return __mtdsplit_parse_uimage(master, pparts, data,
 464                                       uimage_verify_okli);
 465 }
 466
 467 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 468 static const struct of_device_id mtdsplit_uimage_okli_of_match_table[] = {
 469         { .compatible = "openwrt,okli" },
 470         {},
 471 };
 472 #endif
 473
 474 static struct mtd_part_parser uimage_okli_parser = {
 475         .owner = THIS_MODULE,
 476         .name = "okli-fw",
 477 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
 478         .of_match_table = mtdsplit_uimage_okli_of_match_table,
 479 #endif
 480         .parse_fn = mtdsplit_uimage_parse_okli,
 481 };
 482
 483 /**************************************************
 484  * Init
 485  **************************************************/
 486
 487 static int __init mtdsplit_uimage_init(void)
 488 {
 489         register_mtd_parser(&uimage_generic_parser);
 490         register_mtd_parser(&uimage_netgear_parser);
 491         register_mtd_parser(&uimage_edimax_parser);
 492         register_mtd_parser(&uimage_fonfxc_parser);
 493         register_mtd_parser(&uimage_okli_parser);
 494
 495         return 0;
 496 }
 497
 498 module_init(mtdsplit_uimage_init);