Implement Truecrypt ISO loader.

ChangeLog

@@ -1,3 +1,7 @@
+2013-12-17  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Implement Truecrypt ISO loader.
+
 2013-12-17  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/lib/arg.c: Ensure at least a single space between commands.

grub-core/Makefile.core.def

@@ -1623,6 +1623,14 @@ module = {
   enable = i386_pc;
 };
 
+
+module = {
+  name = truecrypt;
+  i386_pc = loader/i386/pc/truecrypt.c;
+  enable = i386_pc;
+};
+
+
 module = {
   name = freedos;
   i386_pc = loader/i386/pc/freedos.c;

grub-core/io/gzio.c

@@ -1093,7 +1093,7 @@ inflate_window (grub_gzio_t gzio)
 	}
     }
 
-  gzio->saved_offset += WSIZE;
+  gzio->saved_offset += gzio->wp;
 
   /* XXX do CRC calculation here! */
 }
@@ -1219,7 +1219,14 @@ grub_gzio_read_real (grub_gzio_t gzio, grub_off_t offset,
       register char *srcaddr;
 
       while (offset >= gzio->saved_offset)
-	inflate_window (gzio);
+	{
+	  inflate_window (gzio);
+	  if (gzio->wp == 0)
+	    goto out;
+	}
+
+      if (gzio->wp == 0)
+	goto out;
 
       srcaddr = (char *) ((offset & (WSIZE - 1)) + gzio->slide);
       size = gzio->saved_offset - offset;
@@ -1234,6 +1241,7 @@ grub_gzio_read_real (grub_gzio_t gzio, grub_off_t offset,
       offset += size;
     }
 
+ out:
   if (grub_errno != GRUB_ERR_NONE)
     ret = -1;
 
@@ -1243,7 +1251,15 @@ grub_gzio_read_real (grub_gzio_t gzio, grub_off_t offset,
 static grub_ssize_t
 grub_gzio_read (grub_file_t file, char *buf, grub_size_t len)
 {
-  return grub_gzio_read_real (file->data, file->offset, buf, len);
+  grub_ssize_t ret;
+  ret = grub_gzio_read_real (file->data, file->offset, buf, len);
+
+  if (!grub_errno && ret != (grub_ssize_t) len)
+    {
+      grub_error (GRUB_ERR_BAD_COMPRESSED_DATA, "premature end of compressed");
+      ret = -1;
+    }
+  return ret;
 }
 
 /* Release everything, including the underlying file object.  */
@@ -1286,10 +1302,38 @@ grub_zlib_decompress (char *inbuf, grub_size_t insize, grub_off_t off,
   ret = grub_gzio_read_real (gzio, off, outbuf, outsize);
   grub_free (gzio);
 
+  if (!grub_errno && ret != (grub_ssize_t) outsize)
+    {
+      grub_error (GRUB_ERR_BAD_COMPRESSED_DATA, "premature end of compressed");
+      ret = -1;
+    }
+
   /* FIXME: Check Adler.  */
   return ret;
 }
 
+grub_ssize_t
+grub_deflate_decompress (char *inbuf, grub_size_t insize, grub_off_t off,
+			 char *outbuf, grub_size_t outsize)
+{
+  grub_gzio_t gzio = 0;
+  grub_ssize_t ret;
+
+  gzio = grub_zalloc (sizeof (*gzio));
+  if (! gzio)
+    return -1;
+  gzio->mem_input = (grub_uint8_t *) inbuf;
+  gzio->mem_input_size = insize;
+  gzio->mem_input_off = 0;
+
+  initialize_tables (gzio);
+
+  ret = grub_gzio_read_real (gzio, off, outbuf, outsize);
+  grub_free (gzio);
+
+  return ret;
+}
+
 
 
 static struct grub_fs grub_gzio_fs =

grub-core/loader/i386/pc/truecrypt.c

@@ -0,0 +1,233 @@
+/* chainloader.c - boot another boot loader */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2002,2004,2007,2009,2010  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/loader.h>
+#include <grub/file.h>
+#include <grub/err.h>
+#include <grub/device.h>
+#include <grub/disk.h>
+#include <grub/misc.h>
+#include <grub/types.h>
+#include <grub/partition.h>
+#include <grub/dl.h>
+#include <grub/command.h>
+#include <grub/machine/biosnum.h>
+#include <grub/i18n.h>
+#include <grub/video.h>
+#include <grub/mm.h>
+#include <grub/cpu/relocator.h>
+#include <grub/deflate.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+static grub_dl_t my_mod;
+static struct grub_relocator *rel;
+static grub_uint32_t edx = 0xffffffff;
+static grub_uint16_t sp;
+static grub_uint32_t destaddr;
+
+#define GRUB_TRUECRYPT_SEGMENT         0x2000
+
+static grub_err_t
+grub_truecrypt_boot (void)
+{
+  grub_uint16_t segment = destaddr >> 4;
+  struct grub_relocator16_state state = { 
+    .cs = segment,
+    .ds = segment,
+    .es = segment,
+    .fs = segment,
+    .gs = segment,
+    .ss = segment,
+    .ip = 0x100,
+    .sp = sp,
+    .edx = edx,
+    .a20 = 1
+  };
+  grub_video_set_mode ("text", 0, 0);
+
+  return grub_relocator16_boot (rel, state);
+}
+
+static grub_err_t
+grub_truecrypt_unload (void)
+{
+  grub_relocator_unload (rel);
+  rel = NULL;
+  grub_dl_unref (my_mod);
+  return GRUB_ERR_NONE;
+}
+
+/* Information on protocol supplied by Attila Lendvai.  */
+#define MAGIC "\0CD001\1EL TORITO SPECIFICATION"
+
+static grub_err_t
+grub_cmd_truecrypt (grub_command_t cmd __attribute__ ((unused)),
+		int argc, char *argv[])
+{
+  grub_file_t file = 0;
+  grub_err_t err;
+  void *truecrypt;
+  grub_size_t truecryptsize;
+  const grub_size_t truecryptmemsize = 42 * 1024;
+  grub_uint8_t dh;
+  grub_uint32_t catalog, rba;
+  grub_uint8_t buf[128];
+  char *compressed = NULL;
+  char *uncompressed = NULL;
+
+  if (argc == 0)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
+
+  rel = NULL;
+
+  grub_dl_ref (my_mod);
+
+  file = grub_file_open (argv[0]);
+  if (! file)
+    goto fail;
+
+  if (grub_file_seek (file, 17 * 2048) == (grub_size_t) -1)
+    goto fail;
+
+  if (grub_file_read (file, buf, sizeof (buf))
+      != sizeof (buf))
+    goto fail;
+
+  if (grub_memcmp (buf, MAGIC, sizeof (MAGIC)) != 0)
+    {
+      grub_error (GRUB_ERR_BAD_OS, "invalid eltorito signature");
+      goto fail;
+    }
+
+  catalog = grub_get_unaligned32 (buf + 0x47);
+
+  if (grub_file_seek (file, catalog * 2048) == (grub_size_t)-1)
+    goto fail;
+
+  if (grub_file_read (file, buf, sizeof (buf))
+      != sizeof (buf))
+    goto fail;
+
+  if (buf[0] != 1 || buf[1] != 0 || buf[0x1e] != 0x55
+      || buf[0x1f] != 0xaa || buf[0x20] != 0x88
+      || buf[0x26] != 1 || buf[0x27] != 0)
+    {
+      grub_error (GRUB_ERR_BAD_OS, "invalid eltorito catalog");
+      goto fail;
+    }
+
+  rba = grub_get_unaligned32 (buf + 0x28);
+
+  if (grub_file_seek (file, rba * 2048 + 0x1b7) == (grub_size_t) -1)
+    goto fail;
+
+  if (grub_file_read (file, &dh, 1)
+      != 1)
+    goto fail;
+
+  if (grub_file_seek (file, rba * 2048 + 512 + 2048) == (grub_size_t) -1)
+    goto fail;
+
+  compressed = grub_malloc (57 * 512);
+  if (!compressed)
+    goto fail;
+
+  if (grub_file_read (file, compressed, 57 * 512)
+      != 57 * 512)
+    goto fail;
+
+  uncompressed = grub_malloc (truecryptmemsize);
+  if (!uncompressed)
+    goto fail;
+
+  /* It's actually gzip but our gzip decompressor isn't able to handle
+     trailing garbage, hence let's use raw decompressor.  */
+  truecryptsize = grub_deflate_decompress (compressed + 10, 57 * 512 - 10,
+					   0, uncompressed, truecryptmemsize);
+  if ((grub_ssize_t) truecryptsize < 0)
+    goto fail;
+
+  if (truecryptmemsize <= truecryptsize + 0x100)
+    {
+      grub_error (GRUB_ERR_BAD_OS, "file is too big");
+      goto fail;
+    }
+
+  rel = grub_relocator_new ();
+  if (!rel)
+    goto fail;
+
+  edx = (dh << 8) | grub_get_root_biosnumber ();
+
+  destaddr = ALIGN_DOWN (grub_min (0x90000, grub_mmap_get_lower ())
+			 - truecryptmemsize, 64 * 1024);
+
+  {
+    grub_relocator_chunk_t ch;
+    err = grub_relocator_alloc_chunk_addr (rel, &ch, destaddr,
+					   truecryptmemsize);
+    if (err)
+      goto fail;
+    truecrypt = get_virtual_current_address (ch);
+  }
+
+  grub_memset (truecrypt, 0, 0x100);
+  grub_memcpy ((char *) truecrypt + 0x100, uncompressed, truecryptsize);
+
+  grub_memset ((char *) truecrypt + truecryptsize + 0x100,
+	       0, truecryptmemsize - truecryptsize - 0x100);
+  sp = truecryptmemsize - 4;
+ 
+  grub_loader_set (grub_truecrypt_boot, grub_truecrypt_unload, 1);
+
+  grub_free (uncompressed);
+  grub_free (compressed);
+
+  return GRUB_ERR_NONE;
+
+ fail:
+
+  if (!grub_errno)
+    return grub_error (GRUB_ERR_BAD_OS, "bad truecrypt ISO");
+
+  if (file)
+    grub_file_close (file);
+
+  grub_truecrypt_unload ();
+
+  grub_free (uncompressed);
+  grub_free (compressed);
+
+  return grub_errno;
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(truecrypt)
+{
+  cmd = grub_register_command ("truecrypt", grub_cmd_truecrypt,
+			       0, N_("Load Truecrypt ISO."));
+  my_mod = mod;
+}
+
+GRUB_MOD_FINI(truecrypt)
+{
+  grub_unregister_command (cmd);
+}

include/grub/deflate.h

@@ -23,4 +23,8 @@ grub_ssize_t
 grub_zlib_decompress (char *inbuf, grub_size_t insize, grub_off_t off,
 		      char *outbuf, grub_size_t outsize);
 
+grub_ssize_t
+grub_deflate_decompress (char *inbuf, grub_size_t insize, grub_off_t off,
+			 char *outbuf, grub_size_t outsize);
+
 #endif