package/mtd/src/trx.c

   1 /*
   2  * trx.c
   3  *
   4  * Copyright (C) 2005 Mike Baker
   5  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stddef.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <sys/mman.h>
  28 #include <sys/stat.h>
  29 #include <string.h>
  30
  31 #include <sys/ioctl.h>
  32 #include "mtd-api.h"
  33 #include "mtd.h"
  34 #include "crc32.h"
  35
  36 #define TRX_MAGIC       0x30524448      /* "HDR0" */
  37 struct trx_header {
  38         unsigned magic;         /* "HDR0" */
  39         unsigned len;           /* Length of file including header */
  40         unsigned crc32;         /* 32-bit CRC from flag_version to end of file */
  41         unsigned flag_version;  /* 0:15 flags, 16:31 version */
  42         unsigned offsets[3];    /* Offsets of partitions from start of header */
  43 };
  44
  45 int
  46 trx_fixup(int fd, const char *name)
  47 {
  48         struct mtd_info_user mtdInfo;
  49         unsigned long len;
  50         struct trx_header *trx;
  51         void *ptr, *scan;
  52         int bfd;
  53
  54         if (ioctl(fd, MEMGETINFO, &mtdInfo) < 0) {
  55                 fprintf(stderr, "Failed to get mtd info\n");
  56                 goto err;
  57         }
  58
  59         len = mtdInfo.size;
  60         if (mtdInfo.size <= 0) {
  61                 fprintf(stderr, "Invalid MTD device size\n");
  62                 goto err;
  63         }
  64
  65         bfd = mtd_open(name, true);
  66         ptr = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, bfd, 0);
  67         if (!ptr || (ptr == (void *) -1)) {
  68                 perror("mmap");
  69                 goto err1;
  70         }
  71
  72         trx = ptr;
  73         if (trx->magic != TRX_MAGIC) {
  74                 fprintf(stderr, "TRX header not found\n");
  75                 goto err;
  76         }
  77
  78         scan = ptr + offsetof(struct trx_header, flag_version);
  79         trx->crc32 = crc32buf(scan, trx->len - (scan - ptr));
  80         msync(ptr, sizeof(struct trx_header), MS_SYNC|MS_INVALIDATE);
  81         munmap(ptr, len);
  82         close(bfd);
  83         return 0;
  84
  85 err1:
  86         close(bfd);
  87 err:
  88         fprintf(stderr, "Error fixing up TRX header\n");
  89         return -1;
  90 }
  91
  92 int
  93 trx_check(int imagefd, const char *mtd, char *buf, int *len)
  94 {
  95         const struct trx_header *trx = (const struct trx_header *) buf;
  96         int fd;
  97
  98         if (strcmp(mtd, "linux") != 0)
  99                 return 1;
 100
 101         *len = read(imagefd, buf, 32);
 102         if (*len < 32) {
 103                 fprintf(stdout, "Could not get image header, file too small (%d bytes)\n", *len);
 104                 return 0;
 105         }
 106
 107         if (trx->magic != TRX_MAGIC || trx->len < sizeof(struct trx_header)) {
 108                 if (quiet < 2) {
 109                         fprintf(stderr, "Bad trx header\n");
 110                         fprintf(stderr, "This is not the correct file format; refusing to flash.\n"
 111                                         "Please specify the correct file or use -f to force.\n");
 112                 }
 113                 return 0;
 114         }
 115
 116         /* check if image fits to mtd device */
 117         fd = mtd_check_open(mtd);
 118         if(fd < 0) {
 119                 fprintf(stderr, "Could not open mtd device: %s\n", mtd);
 120                 exit(1);
 121         }
 122
 123         if(mtdsize < trx->len) {
 124                 fprintf(stderr, "Image too big for partition: %s\n", mtd);
 125                 close(fd);
 126                 return 0;
 127         }
 128
 129         close(fd);
 130         return 1;
 131 }
 132