diff options
Diffstat (limited to 'grub-core/disk/cryptodisk.c')
-rw-r--r-- | grub-core/disk/cryptodisk.c | 1331 |
1 files changed, 1331 insertions, 0 deletions
diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c new file mode 100644 index 0000000..90f82b2 --- /dev/null +++ b/grub-core/disk/cryptodisk.c @@ -0,0 +1,1331 @@ +/* + * 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, grub_size_t log_sector_size, + 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 << 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 << 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: + case GRUB_CRYPTODISK_MODE_IV_PLAIN: + /* + * The IV is a 32 or 64 bit value of the dm-crypt native sector + * number. If using 32 bit IV mode, zero out the most significant + * 32 bits. + */ + { + grub_uint64_t iv64; + + iv64 = grub_cpu_to_le64 (sector << (log_sector_size + - GRUB_CRYPTODISK_IV_LOG_SIZE)); + grub_set_unaligned64 (iv, iv64); + if (dev->mode_iv == GRUB_CRYPTODISK_MODE_IV_PLAIN) + iv[1] = 0; + } + break; + case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64: + /* The IV is the 64 bit byte offset of the sector. */ + iv[1] = grub_cpu_to_le32 (sector >> (GRUB_TYPE_BITS (iv[1]) + - log_sector_size)); + iv[0] = grub_cpu_to_le32 ((sector << log_sector_size) + & GRUB_TYPE_U_MAX (iv[0])); + break; + case GRUB_CRYPTODISK_MODE_IV_BENBI: + { + grub_uint64_t num = (sector << dev->benbi_log) + 1; + iv[sz - 2] = grub_cpu_to_be32 (num >> GRUB_TYPE_BITS (iv[0])); + iv[sz - 1] = grub_cpu_to_be32 (num & GRUB_TYPE_U_MAX (iv[0])); + } + break; + case GRUB_CRYPTODISK_MODE_IV_ESSIV: + iv[0] = grub_cpu_to_le32 (sector & GRUB_TYPE_U_MAX (iv[0])); + 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, + ((grub_size_t) 1 << log_sector_size), iv); + else + err = grub_crypto_cbc_decrypt (dev->cipher, data + i, data + i, + ((grub_size_t) 1 << 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, + ((grub_size_t) 1 << log_sector_size), iv); + else + err = grub_crypto_pcbc_decrypt (dev->cipher, data + i, data + i, + ((grub_size_t) 1 << 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 << 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 << log_sector_size)); + else + err = grub_crypto_ecb_decrypt (dev->cipher, data + i, + data + i, + (1U << 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 << log_sector_size)); + else + err = grub_crypto_ecb_decrypt (dev->cipher, data + i, data + i, + (1U << 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, grub_size_t log_sector_size) +{ + return grub_cryptodisk_endecrypt (dev, data, len, sector, log_sector_size, 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: %" PRIuGRUB_SIZE, + 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: %" PRIuGRUB_SIZE, + 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: %" PRIuGRUB_SIZE, + 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, "plain64", sizeof ("plain64") - 1) == 0) + mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN64; + else if (grub_memcmp (cipheriv, "plain", sizeof ("plain") - 1) == 0) + mode_iv = GRUB_CRYPTODISK_MODE_IV_PLAIN; + 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: %" PRIuGRUB_SIZE, + 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_sectors; + 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_sectors); + + err = grub_disk_read (dev->source_disk, + grub_disk_from_native_sector (disk, sector + dev->offset_sectors), + 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, dev->log_sector_size, 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_sectors); + + gcry_err = grub_cryptodisk_endecrypt (dev, (grub_uint8_t *) tmp, + size << disk->log_sector_size, + sector, disk->log_sector_size, 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_sectors; + 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_sectors); + 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); +} |