package/cfgfs/src/unwraps.c

   1 /* $MirOS: contrib/hosted/fwcf/unwraps.c,v 1.10 2006/09/26 10:25:03 tg Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006
   5  *      Thorsten Glaser <tg@mirbsd.de>
   6  *
   7  * Licensee is hereby permitted to deal in this work without restric-
   8  * tion, including unlimited rights to use, publicly perform, modify,
   9  * merge, distribute, sell, give away or sublicence, provided all co-
  10  * pyright notices above, these terms and the disclaimer are retained
  11  * in all redistributions or reproduced in accompanying documentation
  12  * or other materials provided with binary redistributions.
  13  *
  14  * Licensor offers the work "AS IS" and WITHOUT WARRANTY of any kind,
  15  * express, or implied, to the maximum extent permitted by applicable
  16  * law, without malicious intent or gross negligence; in no event may
  17  * licensor, an author or contributor be held liable for any indirect
  18  * or other damage, or direct damage except proven a consequence of a
  19  * direct error of said person and intended use of this work, loss or
  20  * other issues arising in any way out of its use, even if advised of
  21  * the possibility of such damage or existence of a defect.
  22  */
  23
  24 #include <sys/param.h>
  25 #include <err.h>
  26 #ifdef DEBUG
  27 #include <stdio.h>
  28 #endif
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32
  33 #include "defs.h"
  34 #include "adler.h"
  35 #include "compress.h"
  36 #include "pack.h"
  37 #include "sysdeps.h"
  38
  39 __RCSID("$MirOS: contrib/hosted/fwcf/unwraps.c,v 1.10 2006/09/26 10:25:03 tg Exp $");
  40
  41 char *
  42 fwcf_unpack(int fd, size_t *inner)
  43 {
  44         u_int8_t c, hdrbuf[12];
  45         size_t outer, x_inner, x, len, maxln;
  46         char *cdata, *udata;
  47         ADLER_DECL;
  48
  49         if (inner == NULL)
  50                 inner = &x_inner;
  51
  52         if (read(fd, hdrbuf, 12) != 12)
  53                 err(1, "read");
  54
  55         if (strncmp((const char *)hdrbuf, "FWCF", 4))
  56                 errx(1, "file format error");
  57
  58         outer = LOADT(hdrbuf + 4);
  59         /* we don't need to support older versions, but specification
  60            major 0 and 1 are compatible */
  61         if (hdrbuf[7] > FWCF_VER)
  62                 errx(1, "wrong file version %02Xh", hdrbuf[7]);
  63         *inner = LOADT(hdrbuf + 8);
  64         c = hdrbuf[11];
  65         maxln = ((outer + (DEF_FLASHBLOCK - 1)) / DEF_FLASHBLOCK)
  66             * DEF_FLASHBLOCK;
  67
  68         if (((cdata = malloc(maxln)) == NULL) ||
  69             ((udata = malloc(*inner)) == NULL))
  70                 err(1, "malloc");
  71         memcpy(cdata, hdrbuf, 12);
  72         if (read(fd, cdata + 12, maxln - 12) < (ssize_t)(outer - 12))
  73                 err(1, "read");
  74
  75         len = outer - 4;
  76         ADLER_CALC(cdata);
  77         if ((s1 != LOADW(cdata + outer - 4)) ||
  78             (s2 != LOADW(cdata + outer - 2)))
  79                 errx(1, "crc mismatch: %02X%02X%02X%02X != %04X%04X",
  80                     (u_int8_t)cdata[outer - 1], (u_int8_t)cdata[outer - 2],
  81                     (u_int8_t)cdata[outer - 3], (u_int8_t)cdata[outer - 4],
  82                     s2, s1);
  83
  84         if ((x = compressor_get(c)->decompress(udata, *inner, cdata + 12,
  85             outer - 16)) != *inner)
  86                 errx(1, "size mismatch: decompressed %lu, want %lu", (unsigned long)x,
  87                     (unsigned long)*inner);
  88         push_rndata((u_int8_t *)cdata + outer, maxln - outer);
  89         free(cdata);
  90 #ifdef DEBUG
  91         fprintf(stderr, "fwcf_unpack: decompressed outer %lu inner %lu\n",
  92             (unsigned long)outer, (unsigned long)*inner);
  93 #endif
  94         return (udata);
  95 }