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grub/grub-core/disk/cryptodisk.c
Glenn Washburn 84ff10b1c0 cryptodisk: Use cipher name instead of object in error message 
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2020-09-18 22:31:30 +02:00

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35 KiB
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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003,2007,2010,2011,2019 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/cryptodisk.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/dl.h>
#include <grub/extcmd.h>
#include <grub/i18n.h>
#include <grub/fs.h>
#include <grub/file.h>
#include <grub/procfs.h>
#include <grub/partition.h>
#ifdef GRUB_UTIL
#include <grub/emu/hostdisk.h>
#endif
GRUB_MOD_LICENSE ("GPLv3+");
grub_cryptodisk_dev_t grub_cryptodisk_list;
static const struct grub_arg_option options[] =
{
{"uuid", 'u', 0, N_("Mount by UUID."), 0, 0},
/* TRANSLATORS: It's still restricted to cryptodisks only. */
{"all", 'a', 0, N_("Mount all."), 0, 0},
{"boot", 'b', 0, N_("Mount all volumes with `boot' flag set."), 0, 0},
{0, 0, 0, 0, 0, 0}
};
/* Our irreducible polynom is x^128+x^7+x^2+x+1. Lowest byte of it is: */
#define GF_POLYNOM 0x87
static inline int GF_PER_SECTOR (const struct grub_cryptodisk *dev)
{
return 1U << (dev->log_sector_size - GRUB_CRYPTODISK_GF_LOG_BYTES);
}
static grub_cryptodisk_t cryptodisk_list = NULL;
static grub_uint8_t last_cryptodisk_id = 0;
static void
gf_mul_x (grub_uint8_t *g)
{
int over = 0, over2 = 0;
unsigned j;
for (j = 0; j < GRUB_CRYPTODISK_GF_BYTES; j++)
{
over2 = !!(g[j] & 0x80);
g[j] <<= 1;
g[j] |= over;
over = over2;
}
if (over)
g[0] ^= GF_POLYNOM;
}
static void
gf_mul_x_be (grub_uint8_t *g)
{
int over = 0, over2 = 0;
int j;
for (j = (int) GRUB_CRYPTODISK_GF_BYTES - 1; j >= 0; j--)
{
over2 = !!(g[j] & 0x80);
g[j] <<= 1;
g[j] |= over;
over = over2;
}
if (over)
g[GRUB_CRYPTODISK_GF_BYTES - 1] ^= GF_POLYNOM;
}
static void
gf_mul_be (grub_uint8_t *o, const grub_uint8_t *a, const grub_uint8_t *b)
{
unsigned i;
grub_uint8_t t[GRUB_CRYPTODISK_GF_BYTES];
grub_memset (o, 0, GRUB_CRYPTODISK_GF_BYTES);
grub_memcpy (t, b, GRUB_CRYPTODISK_GF_BYTES);
for (i = 0; i < GRUB_CRYPTODISK_GF_SIZE; i++)
{
if (((a[GRUB_CRYPTODISK_GF_BYTES - i / GRUB_CHAR_BIT - 1] >> (i % GRUB_CHAR_BIT))) & 1)
grub_crypto_xor (o, o, t, GRUB_CRYPTODISK_GF_BYTES);
gf_mul_x_be (t);
}
}
static gcry_err_code_t
grub_crypto_pcbc_decrypt (grub_crypto_cipher_handle_t cipher,
void *out, void *in, grub_size_t size,
void *iv)
{
grub_uint8_t *inptr, *outptr, *end;
grub_uint8_t ivt[GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE];
grub_size_t blocksize;
if (!cipher->cipher->decrypt)
return GPG_ERR_NOT_SUPPORTED;
blocksize = cipher->cipher->blocksize;
if (blocksize == 0 || (((blocksize - 1) & blocksize) != 0)
|| ((size & (blocksize - 1)) != 0))
return GPG_ERR_INV_ARG;
if (blocksize > GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE)
return GPG_ERR_INV_ARG;
end = (grub_uint8_t *) in + size;
for (inptr = in, outptr = out; inptr < end;
inptr += blocksize, outptr += blocksize)
{
grub_memcpy (ivt, inptr, blocksize);
cipher->cipher->decrypt (cipher->ctx, outptr, inptr);
grub_crypto_xor (outptr, outptr, iv, blocksize);
grub_crypto_xor (iv, ivt, outptr, blocksize);
}
return GPG_ERR_NO_ERROR;
}
static gcry_err_code_t
grub_crypto_pcbc_encrypt (grub_crypto_cipher_handle_t cipher,
void *out, void *in, grub_size_t size,
void *iv)
{
grub_uint8_t *inptr, *outptr, *end;
grub_uint8_t ivt[GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE];
grub_size_t blocksize;
if (!cipher->cipher->encrypt)
return GPG_ERR_NOT_SUPPORTED;
blocksize = cipher->cipher->blocksize;
if (blocksize > GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE)
return GPG_ERR_INV_ARG;
if (blocksize == 0 || (((blocksize - 1) & blocksize) != 0)
|| ((size & (blocksize - 1)) != 0))
return GPG_ERR_INV_ARG;
end = (grub_uint8_t *) in + size;
for (inptr = in, outptr = out; inptr < end;
inptr += blocksize, outptr += blocksize)
{
grub_memcpy (ivt, inptr, blocksize);
grub_crypto_xor (outptr, outptr, iv, blocksize);
cipher->cipher->encrypt (cipher->ctx, outptr, inptr);
grub_crypto_xor (iv, ivt, outptr, blocksize);
}
return GPG_ERR_NO_ERROR;
}
struct lrw_sector
{
grub_uint8_t low[GRUB_CRYPTODISK_GF_BYTES];
grub_uint8_t high[GRUB_CRYPTODISK_GF_BYTES];
grub_uint8_t low_byte, low_byte_c;
};
static void
generate_lrw_sector (struct lrw_sector *sec,
const struct grub_cryptodisk *dev,
const grub_uint8_t *iv)
{
grub_uint8_t idx[GRUB_CRYPTODISK_GF_BYTES];
grub_uint16_t c;
int j;
grub_memcpy (idx, iv, GRUB_CRYPTODISK_GF_BYTES);
sec->low_byte = (idx[GRUB_CRYPTODISK_GF_BYTES - 1]
& (GF_PER_SECTOR (dev) - 1));
sec->low_byte_c = (((GF_PER_SECTOR (dev) - 1) & ~sec->low_byte) + 1);
idx[GRUB_CRYPTODISK_GF_BYTES - 1] &= ~(GF_PER_SECTOR (dev) - 1);
gf_mul_be (sec->low, dev->lrw_key, idx);
if (!sec->low_byte)
return;
c = idx[GRUB_CRYPTODISK_GF_BYTES - 1] + GF_PER_SECTOR (dev);
if (c & 0x100)
{
for (j = GRUB_CRYPTODISK_GF_BYTES - 2; j >= 0; j--)
{
idx[j]++;
if (idx[j] != 0)
break;
}
}
idx[GRUB_CRYPTODISK_GF_BYTES - 1] = c;
gf_mul_be (sec->high, dev->lrw_key, idx);
}
static void __attribute__ ((unused))
lrw_xor (const struct lrw_sector *sec,
const struct grub_cryptodisk *dev,
grub_uint8_t *b)
{
unsigned i;
for (i = 0; i < sec->low_byte_c * GRUB_CRYPTODISK_GF_BYTES;
i += GRUB_CRYPTODISK_GF_BYTES)
grub_crypto_xor (b + i, b + i, sec->low, GRUB_CRYPTODISK_GF_BYTES);
grub_crypto_xor (b, b, dev->lrw_precalc + GRUB_CRYPTODISK_GF_BYTES * sec->low_byte,
sec->low_byte_c * GRUB_CRYPTODISK_GF_BYTES);
if (!sec->low_byte)
return;
for (i = sec->low_byte_c * GRUB_CRYPTODISK_GF_BYTES;
i < (1U << dev->log_sector_size); i += GRUB_CRYPTODISK_GF_BYTES)
grub_crypto_xor (b + i, b + i, sec->high, GRUB_CRYPTODISK_GF_BYTES);
grub_crypto_xor (b + sec->low_byte_c * GRUB_CRYPTODISK_GF_BYTES,
b + sec->low_byte_c * GRUB_CRYPTODISK_GF_BYTES,
dev->lrw_precalc, sec->low_byte * GRUB_CRYPTODISK_GF_BYTES);
}
static gcry_err_code_t
grub_cryptodisk_endecrypt (struct grub_cryptodisk *dev,
grub_uint8_t * data, grub_size_t len,
grub_disk_addr_t sector, int do_encrypt)
{
grub_size_t i;
gcry_err_code_t err;
if (dev->cipher->cipher->blocksize > GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE)
return GPG_ERR_INV_ARG;
/* The only mode without IV. */
if (dev->mode == GRUB_CRYPTODISK_MODE_ECB && !dev->rekey)
return (do_encrypt ? grub_crypto_ecb_encrypt (dev->cipher, data, data, len)
: grub_crypto_ecb_decrypt (dev->cipher, data, data, len));
for (i = 0; i < len; i += (1U << dev->log_sector_size))
{
grub_size_t sz = ((dev->cipher->cipher->blocksize
+ sizeof (grub_uint32_t) - 1)
/ sizeof (grub_uint32_t));
grub_uint32_t iv[(GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE + 3) / 4];
if (dev->rekey)
{
grub_uint64_t zone = sector >> dev->rekey_shift;
if (zone != dev->last_rekey)
{
err = dev->rekey (dev, zone);
if (err)
return err;
dev->last_rekey = zone;
}
}
grub_memset (iv, 0, sizeof (iv));
switch (dev->mode_iv)
{
case GRUB_CRYPTODISK_MODE_IV_NULL:
break;
case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64_HASH:
{
grub_uint64_t tmp;
void *ctx;
ctx = grub_zalloc (dev->iv_hash->contextsize);
if (!ctx)
return GPG_ERR_OUT_OF_MEMORY;
tmp = grub_cpu_to_le64 (sector << dev->log_sector_size);
dev->iv_hash->init (ctx);
dev->iv_hash->write (ctx, dev->iv_prefix, dev->iv_prefix_len);
dev->iv_hash->write (ctx, &tmp, sizeof (tmp));
dev->iv_hash->final (ctx);
grub_memcpy (iv, dev->iv_hash->read (ctx), sizeof (iv));
grub_free (ctx);
}
break;
case GRUB_CRYPTODISK_MODE_IV_PLAIN64:
iv[1] = grub_cpu_to_le32 (sector >> 32);
/* FALLTHROUGH */
case GRUB_CRYPTODISK_MODE_IV_PLAIN:
iv[0] = grub_cpu_to_le32 (sector & 0xFFFFFFFF);
break;
case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64:
iv[1] = grub_cpu_to_le32 (sector >> (32 - dev->log_sector_size));
iv[0] = grub_cpu_to_le32 ((sector << dev->log_sector_size)
& 0xFFFFFFFF);
break;
case GRUB_CRYPTODISK_MODE_IV_BENBI:
{
grub_uint64_t num = (sector << dev->benbi_log) + 1;
iv[sz - 2] = grub_cpu_to_be32 (num >> 32);
iv[sz - 1] = grub_cpu_to_be32 (num & 0xFFFFFFFF);
}
break;
case GRUB_CRYPTODISK_MODE_IV_ESSIV:
iv[0] = grub_cpu_to_le32 (sector & 0xFFFFFFFF);
err = grub_crypto_ecb_encrypt (dev->essiv_cipher, iv, iv,
dev->cipher->cipher->blocksize);
if (err)
return err;
}
switch (dev->mode)
{
case GRUB_CRYPTODISK_MODE_CBC:
if (do_encrypt)
err = grub_crypto_cbc_encrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size), iv);
else
err = grub_crypto_cbc_decrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size), iv);
if (err)
return err;
break;
case GRUB_CRYPTODISK_MODE_PCBC:
if (do_encrypt)
err = grub_crypto_pcbc_encrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size), iv);
else
err = grub_crypto_pcbc_decrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size), iv);
if (err)
return err;
break;
case GRUB_CRYPTODISK_MODE_XTS:
{
unsigned j;
err = grub_crypto_ecb_encrypt (dev->secondary_cipher, iv, iv,
dev->cipher->cipher->blocksize);
if (err)
return err;
for (j = 0; j < (1U << dev->log_sector_size);
j += dev->cipher->cipher->blocksize)
{
grub_crypto_xor (data + i + j, data + i + j, iv,
dev->cipher->cipher->blocksize);
if (do_encrypt)
err = grub_crypto_ecb_encrypt (dev->cipher, data + i + j,
data + i + j,
dev->cipher->cipher->blocksize);
else
err = grub_crypto_ecb_decrypt (dev->cipher, data + i + j,
data + i + j,
dev->cipher->cipher->blocksize);
if (err)
return err;
grub_crypto_xor (data + i + j, data + i + j, iv,
dev->cipher->cipher->blocksize);
gf_mul_x ((grub_uint8_t *) iv);
}
}
break;
case GRUB_CRYPTODISK_MODE_LRW:
{
struct lrw_sector sec;
generate_lrw_sector (&sec, dev, (grub_uint8_t *) iv);
lrw_xor (&sec, dev, data + i);
if (do_encrypt)
err = grub_crypto_ecb_encrypt (dev->cipher, data + i,
data + i,
(1U << dev->log_sector_size));
else
err = grub_crypto_ecb_decrypt (dev->cipher, data + i,
data + i,
(1U << dev->log_sector_size));
if (err)
return err;
lrw_xor (&sec, dev, data + i);
}
break;
case GRUB_CRYPTODISK_MODE_ECB:
if (do_encrypt)
err = grub_crypto_ecb_encrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size));
else
err = grub_crypto_ecb_decrypt (dev->cipher, data + i, data + i,
(1U << dev->log_sector_size));
if (err)
return err;
break;
default:
return GPG_ERR_NOT_IMPLEMENTED;
}
sector++;
}
return GPG_ERR_NO_ERROR;
}
gcry_err_code_t
grub_cryptodisk_decrypt (struct grub_cryptodisk *dev,
grub_uint8_t * data, grub_size_t len,
grub_disk_addr_t sector)
{
return grub_cryptodisk_endecrypt (dev, data, len, sector, 0);
}
grub_err_t
grub_cryptodisk_setcipher (grub_cryptodisk_t crypt, const char *ciphername, const char *ciphermode)
{
const char *cipheriv = NULL;
grub_crypto_cipher_handle_t cipher = NULL, secondary_cipher = NULL;
grub_crypto_cipher_handle_t essiv_cipher = NULL;
const gcry_md_spec_t *essiv_hash = NULL;
const struct gcry_cipher_spec *ciph;
grub_cryptodisk_mode_t mode;
grub_cryptodisk_mode_iv_t mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN64;
int benbi_log = 0;
grub_err_t ret = GRUB_ERR_NONE;
ciph = grub_crypto_lookup_cipher_by_name (ciphername);
if (!ciph)
{
ret = grub_error (GRUB_ERR_FILE_NOT_FOUND, "Cipher %s isn't available",
ciphername);
goto err;
}
/* Configure the cipher used for the bulk data. */
cipher = grub_crypto_cipher_open (ciph);
if (!cipher)
{
ret = grub_error (GRUB_ERR_FILE_NOT_FOUND, "Cipher %s could not be initialized",
ciphername);
goto err;
}
/* Configure the cipher mode. */
if (grub_strcmp (ciphermode, "ecb") == 0)
{
mode = GRUB_CRYPTODISK_MODE_ECB;
mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN;
cipheriv = NULL;
}
else if (grub_strcmp (ciphermode, "plain") == 0)
{
mode = GRUB_CRYPTODISK_MODE_CBC;
mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN;
cipheriv = NULL;
}
else if (grub_memcmp (ciphermode, "cbc-", sizeof ("cbc-") - 1) == 0)
{
mode = GRUB_CRYPTODISK_MODE_CBC;
cipheriv = ciphermode + sizeof ("cbc-") - 1;
}
else if (grub_memcmp (ciphermode, "pcbc-", sizeof ("pcbc-") - 1) == 0)
{
mode = GRUB_CRYPTODISK_MODE_PCBC;
cipheriv = ciphermode + sizeof ("pcbc-") - 1;
}
else if (grub_memcmp (ciphermode, "xts-", sizeof ("xts-") - 1) == 0)
{
mode = GRUB_CRYPTODISK_MODE_XTS;
cipheriv = ciphermode + sizeof ("xts-") - 1;
secondary_cipher = grub_crypto_cipher_open (ciph);
if (!secondary_cipher)
{
ret = grub_error (GRUB_ERR_FILE_NOT_FOUND,
"Secondary cipher %s isn't available", ciphername);
goto err;
}
if (cipher->cipher->blocksize != GRUB_CRYPTODISK_GF_BYTES)
{
ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Unsupported XTS block size: %d",
cipher->cipher->blocksize);
goto err;
}
if (secondary_cipher->cipher->blocksize != GRUB_CRYPTODISK_GF_BYTES)
{
ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Unsupported XTS block size: %d",
secondary_cipher->cipher->blocksize);
goto err;
}
}
else if (grub_memcmp (ciphermode, "lrw-", sizeof ("lrw-") - 1) == 0)
{
mode = GRUB_CRYPTODISK_MODE_LRW;
cipheriv = ciphermode + sizeof ("lrw-") - 1;
if (cipher->cipher->blocksize != GRUB_CRYPTODISK_GF_BYTES)
{
ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Unsupported LRW block size: %d",
cipher->cipher->blocksize);
goto err;
}
}
else
{
ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Unknown cipher mode: %s",
ciphermode);
goto err;
}
if (cipheriv == NULL)
;
else if (grub_memcmp (cipheriv, "plain", sizeof ("plain") - 1) == 0)
mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN;
else if (grub_memcmp (cipheriv, "plain64", sizeof ("plain64") - 1) == 0)
mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN64;
else if (grub_memcmp (cipheriv, "benbi", sizeof ("benbi") - 1) == 0)
{
if (cipher->cipher->blocksize & (cipher->cipher->blocksize - 1)
|| cipher->cipher->blocksize == 0)
grub_error (GRUB_ERR_BAD_ARGUMENT, "Unsupported benbi blocksize: %d",
cipher->cipher->blocksize);
/* FIXME should we return an error here? */
for (benbi_log = 0;
(cipher->cipher->blocksize << benbi_log) < GRUB_DISK_SECTOR_SIZE;
benbi_log++);
mode_iv = GRUB_CRYPTODISK_MODE_IV_BENBI;
}
else if (grub_memcmp (cipheriv, "null", sizeof ("null") - 1) == 0)
mode_iv = GRUB_CRYPTODISK_MODE_IV_NULL;
else if (grub_memcmp (cipheriv, "essiv:", sizeof ("essiv:") - 1) == 0)
{
const char *hash_str = cipheriv + 6;
mode_iv = GRUB_CRYPTODISK_MODE_IV_ESSIV;
/* Configure the hash and cipher used for ESSIV. */
essiv_hash = grub_crypto_lookup_md_by_name (hash_str);
if (!essiv_hash)
{
ret = grub_error (GRUB_ERR_FILE_NOT_FOUND,
"Couldn't load %s hash", hash_str);
goto err;
}
essiv_cipher = grub_crypto_cipher_open (ciph);
if (!essiv_cipher)
{
ret = grub_error (GRUB_ERR_FILE_NOT_FOUND,
"Couldn't load %s cipher", ciphername);
goto err;
}
}
else
{
ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Unknown IV mode: %s",
cipheriv);
goto err;
}
crypt->cipher = cipher;
crypt->benbi_log = benbi_log;
crypt->mode = mode;
crypt->mode_iv = mode_iv;
crypt->secondary_cipher = secondary_cipher;
crypt->essiv_cipher = essiv_cipher;
crypt->essiv_hash = essiv_hash;
err:
if (ret)
{
grub_crypto_cipher_close (cipher);
grub_crypto_cipher_close (secondary_cipher);
}
return ret;
}
gcry_err_code_t
grub_cryptodisk_setkey (grub_cryptodisk_t dev, grub_uint8_t *key, grub_size_t keysize)
{
gcry_err_code_t err;
int real_keysize;
real_keysize = keysize;
if (dev->mode == GRUB_CRYPTODISK_MODE_XTS)
real_keysize /= 2;
if (dev->mode == GRUB_CRYPTODISK_MODE_LRW)
real_keysize -= dev->cipher->cipher->blocksize;
/* Set the PBKDF2 output as the cipher key. */
err = grub_crypto_cipher_set_key (dev->cipher, key, real_keysize);
if (err)
return err;
grub_memcpy (dev->key, key, keysize);
dev->keysize = keysize;
/* Configure ESSIV if necessary. */
if (dev->mode_iv == GRUB_CRYPTODISK_MODE_IV_ESSIV)
{
grub_size_t essiv_keysize = dev->essiv_hash->mdlen;
grub_uint8_t hashed_key[GRUB_CRYPTO_MAX_MDLEN];
if (essiv_keysize > GRUB_CRYPTO_MAX_MDLEN)
return GPG_ERR_INV_ARG;
grub_crypto_hash (dev->essiv_hash, hashed_key, key, keysize);
err = grub_crypto_cipher_set_key (dev->essiv_cipher,
hashed_key, essiv_keysize);
if (err)
return err;
}
if (dev->mode == GRUB_CRYPTODISK_MODE_XTS)
{
err = grub_crypto_cipher_set_key (dev->secondary_cipher,
key + real_keysize,
keysize / 2);
if (err)
return err;
}
if (dev->mode == GRUB_CRYPTODISK_MODE_LRW)
{
unsigned i;
grub_uint8_t idx[GRUB_CRYPTODISK_GF_BYTES];
grub_free (dev->lrw_precalc);
grub_memcpy (dev->lrw_key, key + real_keysize,
dev->cipher->cipher->blocksize);
dev->lrw_precalc = grub_malloc ((1U << dev->log_sector_size));
if (!dev->lrw_precalc)
return GPG_ERR_OUT_OF_MEMORY;
grub_memset (idx, 0, GRUB_CRYPTODISK_GF_BYTES);
for (i = 0; i < (1U << dev->log_sector_size);
i += GRUB_CRYPTODISK_GF_BYTES)
{
idx[GRUB_CRYPTODISK_GF_BYTES - 1] = i / GRUB_CRYPTODISK_GF_BYTES;
gf_mul_be (dev->lrw_precalc + i, idx, dev->lrw_key);
}
}
return GPG_ERR_NO_ERROR;
}
static int
grub_cryptodisk_iterate (grub_disk_dev_iterate_hook_t hook, void *hook_data,
grub_disk_pull_t pull)
{
grub_cryptodisk_t i;
if (pull != GRUB_DISK_PULL_NONE)
return 0;
for (i = cryptodisk_list; i != NULL; i = i->next)
{
char buf[30];
grub_snprintf (buf, sizeof (buf), "crypto%lu", i->id);
if (hook (buf, hook_data))
return 1;
}
return GRUB_ERR_NONE;
}
static grub_err_t
grub_cryptodisk_open (const char *name, grub_disk_t disk)
{
grub_cryptodisk_t dev;
if (grub_memcmp (name, "crypto", sizeof ("crypto") - 1) != 0)
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "No such device");
if (grub_memcmp (name, "cryptouuid/", sizeof ("cryptouuid/") - 1) == 0)
{
for (dev = cryptodisk_list; dev != NULL; dev = dev->next)
if (grub_strcasecmp (name + sizeof ("cryptouuid/") - 1, dev->uuid) == 0)
break;
}
else
{
unsigned long id = grub_strtoul (name + sizeof ("crypto") - 1, 0, 0);
if (grub_errno)
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "No such device");
/* Search for requested device in the list of CRYPTODISK devices. */
for (dev = cryptodisk_list; dev != NULL; dev = dev->next)
if (dev->id == id)
break;
}
if (!dev)
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "No such device");
disk->log_sector_size = dev->log_sector_size;
#ifdef GRUB_UTIL
if (dev->cheat)
{
if (!GRUB_UTIL_FD_IS_VALID (dev->cheat_fd))
dev->cheat_fd = grub_util_fd_open (dev->cheat, GRUB_UTIL_FD_O_RDONLY);
if (!GRUB_UTIL_FD_IS_VALID (dev->cheat_fd))
return grub_error (GRUB_ERR_IO, N_("cannot open `%s': %s"),
dev->cheat, grub_util_fd_strerror ());
}
#endif
if (!dev->source_disk)
{
grub_dprintf ("cryptodisk", "Opening device %s\n", name);
/* Try to open the source disk and populate the requested disk. */
dev->source_disk = grub_disk_open (dev->source);
if (!dev->source_disk)
return grub_errno;
}
disk->data = dev;
disk->total_sectors = dev->total_length;
disk->max_agglomerate = GRUB_DISK_MAX_MAX_AGGLOMERATE;
disk->id = dev->id;
dev->ref++;
return GRUB_ERR_NONE;
}
static void
grub_cryptodisk_close (grub_disk_t disk)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
grub_dprintf ("cryptodisk", "Closing disk\n");
dev->ref--;
if (dev->ref != 0)
return;
#ifdef GRUB_UTIL
if (dev->cheat)
{
grub_util_fd_close (dev->cheat_fd);
dev->cheat_fd = GRUB_UTIL_FD_INVALID;
}
#endif
grub_disk_close (dev->source_disk);
dev->source_disk = NULL;
}
static grub_err_t
grub_cryptodisk_read (grub_disk_t disk, grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
grub_err_t err;
gcry_err_code_t gcry_err;
#ifdef GRUB_UTIL
if (dev->cheat)
{
int r;
r = grub_util_fd_seek (dev->cheat_fd, sector << disk->log_sector_size);
if (r)
return grub_error (GRUB_ERR_BAD_DEVICE, N_("cannot seek `%s': %s"),
dev->cheat, grub_util_fd_strerror ());
if (grub_util_fd_read (dev->cheat_fd, buf, size << disk->log_sector_size)
!= (ssize_t) (size << disk->log_sector_size))
return grub_error (GRUB_ERR_READ_ERROR, N_("cannot read `%s': %s"),
dev->cheat, grub_util_fd_strerror ());
return GRUB_ERR_NONE;
}
#endif
grub_dprintf ("cryptodisk",
"Reading %" PRIuGRUB_SIZE " sectors from sector 0x%"
PRIxGRUB_UINT64_T " with offset of %" PRIuGRUB_UINT64_T "\n",
size, sector, dev->offset);
err = grub_disk_read (dev->source_disk,
grub_disk_from_native_sector (disk, sector + dev->offset),
0, size << disk->log_sector_size, buf);
if (err)
{
grub_dprintf ("cryptodisk", "grub_disk_read failed with error %d\n", err);
return err;
}
gcry_err = grub_cryptodisk_endecrypt (dev, (grub_uint8_t *) buf,
size << disk->log_sector_size,
sector, 0);
return grub_crypto_gcry_error (gcry_err);
}
static grub_err_t
grub_cryptodisk_write (grub_disk_t disk, grub_disk_addr_t sector,
grub_size_t size, const char *buf)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
gcry_err_code_t gcry_err;
char *tmp;
grub_err_t err;
#ifdef GRUB_UTIL
if (dev->cheat)
{
int r;
r = grub_util_fd_seek (dev->cheat_fd, sector << disk->log_sector_size);
if (r)
return grub_error (GRUB_ERR_BAD_DEVICE, N_("cannot seek `%s': %s"),
dev->cheat, grub_util_fd_strerror ());
if (grub_util_fd_write (dev->cheat_fd, buf, size << disk->log_sector_size)
!= (ssize_t) (size << disk->log_sector_size))
return grub_error (GRUB_ERR_READ_ERROR, N_("cannot read `%s': %s"),
dev->cheat, grub_util_fd_strerror ());
return GRUB_ERR_NONE;
}
#endif
tmp = grub_malloc (size << disk->log_sector_size);
if (!tmp)
return grub_errno;
grub_memcpy (tmp, buf, size << disk->log_sector_size);
grub_dprintf ("cryptodisk",
"Writing %" PRIuGRUB_SIZE " sectors to sector 0x%"
PRIxGRUB_UINT64_T " with offset of %" PRIuGRUB_UINT64_T "\n",
size, sector, dev->offset);
gcry_err = grub_cryptodisk_endecrypt (dev, (grub_uint8_t *) tmp,
size << disk->log_sector_size,
sector, 1);
if (gcry_err)
{
grub_free (tmp);
return grub_crypto_gcry_error (gcry_err);
}
/* Since ->write was called so disk.mod is loaded but be paranoid */
sector = sector + dev->offset;
if (grub_disk_write_weak)
err = grub_disk_write_weak (dev->source_disk,
grub_disk_from_native_sector (disk, sector),
0, size << disk->log_sector_size, tmp);
else
err = grub_error (GRUB_ERR_BUG, "disk.mod not loaded");
grub_free (tmp);
return err;
}
#ifdef GRUB_UTIL
static grub_disk_memberlist_t
grub_cryptodisk_memberlist (grub_disk_t disk)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
grub_disk_memberlist_t list = NULL;
list = grub_malloc (sizeof (*list));
if (list)
{
list->disk = dev->source_disk;
list->next = NULL;
}
return list;
}
#endif
static void
cryptodisk_cleanup (void)
{
#if 0
grub_cryptodisk_t dev = cryptodisk_list;
grub_cryptodisk_t tmp;
while (dev != NULL)
{
grub_free (dev->source);
grub_free (dev->cipher);
grub_free (dev->secondary_cipher);
grub_free (dev->essiv_cipher);
tmp = dev->next;
grub_free (dev);
dev = tmp;
}
#endif
}
grub_err_t
grub_cryptodisk_insert (grub_cryptodisk_t newdev, const char *name,
grub_disk_t source)
{
newdev->source = grub_strdup (name);
if (!newdev->source)
{
grub_free (newdev);
return grub_errno;
}
newdev->id = last_cryptodisk_id++;
newdev->source_id = source->id;
newdev->source_dev_id = source->dev->id;
newdev->partition_start = grub_partition_get_start (source->partition);
newdev->next = cryptodisk_list;
cryptodisk_list = newdev;
return GRUB_ERR_NONE;
}
grub_cryptodisk_t
grub_cryptodisk_get_by_uuid (const char *uuid)
{
grub_cryptodisk_t dev;
for (dev = cryptodisk_list; dev != NULL; dev = dev->next)
if (grub_strcasecmp (dev->uuid, uuid) == 0)
return dev;
return NULL;
}
grub_cryptodisk_t
grub_cryptodisk_get_by_source_disk (grub_disk_t disk)
{
grub_cryptodisk_t dev;
for (dev = cryptodisk_list; dev != NULL; dev = dev->next)
if (dev->source_id == disk->id && dev->source_dev_id == disk->dev->id)
if ((disk->partition && grub_partition_get_start (disk->partition) == dev->partition_start) ||
(!disk->partition && dev->partition_start == 0))
return dev;
return NULL;
}
#ifdef GRUB_UTIL
grub_err_t
grub_cryptodisk_cheat_insert (grub_cryptodisk_t newdev, const char *name,
grub_disk_t source, const char *cheat)
{
newdev->cheat = grub_strdup (cheat);
newdev->source = grub_strdup (name);
if (!newdev->source || !newdev->cheat)
{
grub_free (newdev->source);
grub_free (newdev->cheat);
return grub_errno;
}
newdev->cheat_fd = GRUB_UTIL_FD_INVALID;
newdev->source_id = source->id;
newdev->source_dev_id = source->dev->id;
newdev->partition_start = grub_partition_get_start (source->partition);
newdev->id = last_cryptodisk_id++;
newdev->next = cryptodisk_list;
cryptodisk_list = newdev;
return GRUB_ERR_NONE;
}
void
grub_util_cryptodisk_get_abstraction (grub_disk_t disk,
void (*cb) (const char *val, void *data),
void *data)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
cb ("cryptodisk", data);
cb (dev->modname, data);
if (dev->cipher)
cb (dev->cipher->cipher->modname, data);
if (dev->secondary_cipher)
cb (dev->secondary_cipher->cipher->modname, data);
if (dev->essiv_cipher)
cb (dev->essiv_cipher->cipher->modname, data);
if (dev->hash)
cb (dev->hash->modname, data);
if (dev->essiv_hash)
cb (dev->essiv_hash->modname, data);
if (dev->iv_hash)
cb (dev->iv_hash->modname, data);
}
const char *
grub_util_cryptodisk_get_uuid (grub_disk_t disk)
{
grub_cryptodisk_t dev = (grub_cryptodisk_t) disk->data;
return dev->uuid;
}
#endif
static int check_boot, have_it;
static char *search_uuid;
static void
cryptodisk_close (grub_cryptodisk_t dev)
{
grub_crypto_cipher_close (dev->cipher);
grub_crypto_cipher_close (dev->secondary_cipher);
grub_crypto_cipher_close (dev->essiv_cipher);
grub_free (dev);
}
static grub_err_t
grub_cryptodisk_scan_device_real (const char *name, grub_disk_t source)
{
grub_err_t err;
grub_cryptodisk_t dev;
grub_cryptodisk_dev_t cr;
dev = grub_cryptodisk_get_by_source_disk (source);
if (dev)
return GRUB_ERR_NONE;
FOR_CRYPTODISK_DEVS (cr)
{
dev = cr->scan (source, search_uuid, check_boot);
if (grub_errno)
return grub_errno;
if (!dev)
continue;
err = cr->recover_key (source, dev);
if (err)
{
cryptodisk_close (dev);
return err;
}
grub_cryptodisk_insert (dev, name, source);
have_it = 1;
return GRUB_ERR_NONE;
}
return GRUB_ERR_NONE;
}
#ifdef GRUB_UTIL
#include <grub/util/misc.h>
grub_err_t
grub_cryptodisk_cheat_mount (const char *sourcedev, const char *cheat)
{
grub_err_t err;
grub_cryptodisk_t dev;
grub_cryptodisk_dev_t cr;
grub_disk_t source;
/* Try to open disk. */
source = grub_disk_open (sourcedev);
if (!source)
return grub_errno;
dev = grub_cryptodisk_get_by_source_disk (source);
if (dev)
{
grub_disk_close (source);
return GRUB_ERR_NONE;
}
FOR_CRYPTODISK_DEVS (cr)
{
dev = cr->scan (source, search_uuid, check_boot);
if (grub_errno)
return grub_errno;
if (!dev)
continue;
grub_util_info ("cheatmounted %s (%s) at %s", sourcedev, dev->modname,
cheat);
err = grub_cryptodisk_cheat_insert (dev, sourcedev, source, cheat);
grub_disk_close (source);
if (err)
grub_free (dev);
return GRUB_ERR_NONE;
}
grub_disk_close (source);
return GRUB_ERR_NONE;
}
#endif
static int
grub_cryptodisk_scan_device (const char *name,
void *data __attribute__ ((unused)))
{
grub_err_t err;
grub_disk_t source;
/* Try to open disk. */
source = grub_disk_open (name);
if (!source)
{
grub_print_error ();
return 0;
}
err = grub_cryptodisk_scan_device_real (name, source);
grub_disk_close (source);
if (err)
grub_print_error ();
return have_it && search_uuid ? 1 : 0;
}
static grub_err_t
grub_cmd_cryptomount (grub_extcmd_context_t ctxt, int argc, char **args)
{
struct grub_arg_list *state = ctxt->state;
if (argc < 1 && !state[1].set && !state[2].set)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "device name required");
have_it = 0;
if (state[0].set)
{
grub_cryptodisk_t dev;
dev = grub_cryptodisk_get_by_uuid (args[0]);
if (dev)
{
grub_dprintf ("cryptodisk",
"already mounted as crypto%lu\n", dev->id);
return GRUB_ERR_NONE;
}
check_boot = state[2].set;
search_uuid = args[0];
grub_device_iterate (&grub_cryptodisk_scan_device, NULL);
search_uuid = NULL;
if (!have_it)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "no such cryptodisk found");
return GRUB_ERR_NONE;
}
else if (state[1].set || (argc == 0 && state[2].set))
{
search_uuid = NULL;
check_boot = state[2].set;
grub_device_iterate (&grub_cryptodisk_scan_device, NULL);
search_uuid = NULL;
return GRUB_ERR_NONE;
}
else
{
grub_err_t err;
grub_disk_t disk;
grub_cryptodisk_t dev;
char *diskname;
char *disklast = NULL;
grub_size_t len;
search_uuid = NULL;
check_boot = state[2].set;
diskname = args[0];
len = grub_strlen (diskname);
if (len && diskname[0] == '(' && diskname[len - 1] == ')')
{
disklast = &diskname[len - 1];
*disklast = '\0';
diskname++;
}
disk = grub_disk_open (diskname);
if (!disk)
{
if (disklast)
*disklast = ')';
return grub_errno;
}
dev = grub_cryptodisk_get_by_source_disk (disk);
if (dev)
{
grub_dprintf ("cryptodisk", "already mounted as crypto%lu\n", dev->id);
grub_disk_close (disk);
if (disklast)
*disklast = ')';
return GRUB_ERR_NONE;
}
err = grub_cryptodisk_scan_device_real (diskname, disk);
grub_disk_close (disk);
if (disklast)
*disklast = ')';
return err;
}
}
static struct grub_disk_dev grub_cryptodisk_dev = {
.name = "cryptodisk",
.id = GRUB_DISK_DEVICE_CRYPTODISK_ID,
.disk_iterate = grub_cryptodisk_iterate,
.disk_open = grub_cryptodisk_open,
.disk_close = grub_cryptodisk_close,
.disk_read = grub_cryptodisk_read,
.disk_write = grub_cryptodisk_write,
#ifdef GRUB_UTIL
.disk_memberlist = grub_cryptodisk_memberlist,
#endif
.next = 0
};
static char
hex (grub_uint8_t val)
{
if (val < 10)
return '0' + val;
return 'a' + val - 10;
}
/* Open a file named NAME and initialize FILE. */
static char *
luks_script_get (grub_size_t *sz)
{
grub_cryptodisk_t i;
grub_size_t size = 0;
char *ptr, *ret;
*sz = 0;
for (i = cryptodisk_list; i != NULL; i = i->next)
if (grub_strcmp (i->modname, "luks") == 0)
{
size += sizeof ("luks_mount ");
size += grub_strlen (i->uuid);
size += grub_strlen (i->cipher->cipher->name);
size += 54;
if (i->essiv_hash)
size += grub_strlen (i->essiv_hash->name);
size += i->keysize * 2;
}
ret = grub_malloc (size + 1);
if (!ret)
return 0;
ptr = ret;
for (i = cryptodisk_list; i != NULL; i = i->next)
if (grub_strcmp (i->modname, "luks") == 0)
{
unsigned j;
const char *iptr;
ptr = grub_stpcpy (ptr, "luks_mount ");
ptr = grub_stpcpy (ptr, i->uuid);
*ptr++ = ' ';
grub_snprintf (ptr, 21, "%" PRIuGRUB_UINT64_T " ", i->offset);
while (*ptr)
ptr++;
for (iptr = i->cipher->cipher->name; *iptr; iptr++)
*ptr++ = grub_tolower (*iptr);
switch (i->mode)
{
case GRUB_CRYPTODISK_MODE_ECB:
ptr = grub_stpcpy (ptr, "-ecb");
break;
case GRUB_CRYPTODISK_MODE_CBC:
ptr = grub_stpcpy (ptr, "-cbc");
break;
case GRUB_CRYPTODISK_MODE_PCBC:
ptr = grub_stpcpy (ptr, "-pcbc");
break;
case GRUB_CRYPTODISK_MODE_XTS:
ptr = grub_stpcpy (ptr, "-xts");
break;
case GRUB_CRYPTODISK_MODE_LRW:
ptr = grub_stpcpy (ptr, "-lrw");
break;
}
switch (i->mode_iv)
{
case GRUB_CRYPTODISK_MODE_IV_NULL:
ptr = grub_stpcpy (ptr, "-null");
break;
case GRUB_CRYPTODISK_MODE_IV_PLAIN:
ptr = grub_stpcpy (ptr, "-plain");
break;
case GRUB_CRYPTODISK_MODE_IV_PLAIN64:
ptr = grub_stpcpy (ptr, "-plain64");
break;
case GRUB_CRYPTODISK_MODE_IV_BENBI:
ptr = grub_stpcpy (ptr, "-benbi");
break;
case GRUB_CRYPTODISK_MODE_IV_ESSIV:
ptr = grub_stpcpy (ptr, "-essiv:");
ptr = grub_stpcpy (ptr, i->essiv_hash->name);
break;
case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64:
case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64_HASH:
break;
}
*ptr++ = ' ';
for (j = 0; j < i->keysize; j++)
{
*ptr++ = hex (i->key[j] >> 4);
*ptr++ = hex (i->key[j] & 0xf);
}
*ptr++ = '\n';
}
*ptr = '\0';
*sz = ptr - ret;
return ret;
}
struct grub_procfs_entry luks_script =
{
.name = "luks_script",
.get_contents = luks_script_get
};
static grub_extcmd_t cmd;
GRUB_MOD_INIT (cryptodisk)
{
grub_disk_dev_register (&grub_cryptodisk_dev);
cmd = grub_register_extcmd ("cryptomount", grub_cmd_cryptomount, 0,
N_("SOURCE|-u UUID|-a|-b"),
N_("Mount a crypto device."), options);
grub_procfs_register ("luks_script", &luks_script);
}
GRUB_MOD_FINI (cryptodisk)
{
grub_disk_dev_unregister (&grub_cryptodisk_dev);
cryptodisk_cleanup ();
grub_unregister_extcmd (cmd);
grub_procfs_unregister (&luks_script);
}
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