diff options
Diffstat (limited to 'grub-core/loader/i386/pc/truecrypt.c')
| -rw-r--r-- | grub-core/loader/i386/pc/truecrypt.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/grub-core/loader/i386/pc/truecrypt.c b/grub-core/loader/i386/pc/truecrypt.c new file mode 100644 index 0000000..cbeeec7 --- /dev/null +++ b/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], GRUB_FILE_TYPE_TRUECRYPT); + 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) + 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); +} |