summaryrefslogtreecommitdiffstats
path: root/grub-core/fs/zfs/zfscrypt.c
diff options
context:
space:
mode:
Diffstat (limited to 'grub-core/fs/zfs/zfscrypt.c')
-rw-r--r--grub-core/fs/zfs/zfscrypt.c491
1 files changed, 491 insertions, 0 deletions
diff --git a/grub-core/fs/zfs/zfscrypt.c b/grub-core/fs/zfs/zfscrypt.c
new file mode 100644
index 0000000..de3b015
--- /dev/null
+++ b/grub-core/fs/zfs/zfscrypt.c
@@ -0,0 +1,491 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2011 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/err.h>
+#include <grub/file.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/disk.h>
+#include <grub/partition.h>
+#include <grub/safemath.h>
+#include <grub/dl.h>
+#include <grub/types.h>
+#include <grub/zfs/zfs.h>
+#include <grub/zfs/zio.h>
+#include <grub/zfs/dnode.h>
+#include <grub/zfs/uberblock_impl.h>
+#include <grub/zfs/vdev_impl.h>
+#include <grub/zfs/zio_checksum.h>
+#include <grub/zfs/zap_impl.h>
+#include <grub/zfs/zap_leaf.h>
+#include <grub/zfs/zfs_znode.h>
+#include <grub/zfs/dmu.h>
+#include <grub/zfs/dmu_objset.h>
+#include <grub/zfs/sa_impl.h>
+#include <grub/zfs/dsl_dir.h>
+#include <grub/zfs/dsl_dataset.h>
+#include <grub/crypto.h>
+#include <grub/extcmd.h>
+#include <grub/i18n.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+/*
+ Mostly based on following article:
+ https://blogs.oracle.com/darren/entry/zfs_encryption_what_is_on
+ */
+
+enum grub_zfs_algo
+ {
+ GRUB_ZFS_ALGO_CCM,
+ GRUB_ZFS_ALGO_GCM,
+ };
+
+struct grub_zfs_key
+{
+ grub_uint64_t algo;
+ grub_uint8_t enc_nonce[13];
+ grub_uint8_t unused[3];
+ grub_uint8_t enc_key[48];
+ grub_uint8_t unknown_purpose_nonce[13];
+ grub_uint8_t unused2[3];
+ grub_uint8_t unknown_purpose_key[48];
+};
+
+struct grub_zfs_wrap_key
+{
+ struct grub_zfs_wrap_key *next;
+ grub_size_t keylen;
+ int is_passphrase;
+ grub_uint64_t key[0];
+};
+
+static struct grub_zfs_wrap_key *zfs_wrap_keys;
+
+grub_err_t
+grub_zfs_add_key (grub_uint8_t *key_in,
+ grub_size_t keylen,
+ int passphrase)
+{
+ struct grub_zfs_wrap_key *key;
+ grub_size_t sz;
+
+ if (!passphrase && keylen > 32)
+ keylen = 32;
+ if (grub_add (sizeof (*key), keylen, &sz))
+ return GRUB_ERR_OUT_OF_RANGE;
+ key = grub_malloc (sz);
+ if (!key)
+ return grub_errno;
+ key->is_passphrase = passphrase;
+ key->keylen = keylen;
+ grub_memcpy (key->key, key_in, keylen);
+ key->next = zfs_wrap_keys;
+ zfs_wrap_keys = key;
+ return GRUB_ERR_NONE;
+}
+
+static gcry_err_code_t
+grub_ccm_decrypt (grub_crypto_cipher_handle_t cipher,
+ grub_uint8_t *out, const grub_uint8_t *in,
+ grub_size_t psize,
+ void *mac_out, const void *nonce,
+ unsigned l, unsigned m)
+{
+ grub_uint8_t iv[16];
+ grub_uint8_t mul[16];
+ grub_uint32_t mac[4];
+ unsigned i, j;
+ gcry_err_code_t err;
+
+ grub_memcpy (iv + 1, nonce, 15 - l);
+
+ iv[0] = (l - 1) | (((m-2) / 2) << 3);
+ for (j = 0; j < l; j++)
+ iv[15 - j] = psize >> (8 * j);
+ err = grub_crypto_ecb_encrypt (cipher, mac, iv, 16);
+ if (err)
+ return err;
+
+ iv[0] = l - 1;
+
+ for (i = 0; i < (psize + 15) / 16; i++)
+ {
+ grub_size_t csize;
+ csize = 16;
+ if (csize > psize - 16 * i)
+ csize = psize - 16 * i;
+ for (j = 0; j < l; j++)
+ iv[15 - j] = (i + 1) >> (8 * j);
+ err = grub_crypto_ecb_encrypt (cipher, mul, iv, 16);
+ if (err)
+ return err;
+ grub_crypto_xor (out + 16 * i, in + 16 * i, mul, csize);
+ grub_crypto_xor (mac, mac, out + 16 * i, csize);
+ err = grub_crypto_ecb_encrypt (cipher, mac, mac, 16);
+ if (err)
+ return err;
+ }
+ for (j = 0; j < l; j++)
+ iv[15 - j] = 0;
+ err = grub_crypto_ecb_encrypt (cipher, mul, iv, 16);
+ if (err)
+ return err;
+ if (mac_out)
+ grub_crypto_xor (mac_out, mac, mul, m);
+ return GPG_ERR_NO_ERROR;
+}
+
+static void
+grub_gcm_mul_x (grub_uint8_t *a)
+{
+ int i;
+ int c = 0, d = 0;
+ for (i = 0; i < 16; i++)
+ {
+ c = a[i] & 0x1;
+ a[i] = (a[i] >> 1) | (d << 7);
+ d = c;
+ }
+ if (d)
+ a[0] ^= 0xe1;
+}
+
+static void
+grub_gcm_mul (grub_uint8_t *a, const grub_uint8_t *b)
+{
+ grub_uint8_t res[16], bs[16];
+ int i;
+ grub_memcpy (bs, b, 16);
+ grub_memset (res, 0, 16);
+ for (i = 0; i < 128; i++)
+ {
+ if ((a[i / 8] << (i % 8)) & 0x80)
+ grub_crypto_xor (res, res, bs, 16);
+ grub_gcm_mul_x (bs);
+ }
+
+ grub_memcpy (a, res, 16);
+}
+
+static gcry_err_code_t
+grub_gcm_decrypt (grub_crypto_cipher_handle_t cipher,
+ grub_uint8_t *out, const grub_uint8_t *in,
+ grub_size_t psize,
+ void *mac_out, const void *nonce,
+ unsigned nonce_len, unsigned m)
+{
+ grub_uint8_t iv[16];
+ grub_uint8_t mul[16];
+ grub_uint8_t mac[16], h[16], mac_xor[16];
+ unsigned i, j;
+ gcry_err_code_t err;
+
+ grub_memset (mac, 0, sizeof (mac));
+
+ err = grub_crypto_ecb_encrypt (cipher, h, mac, 16);
+ if (err)
+ return err;
+
+ if (nonce_len == 12)
+ {
+ grub_memcpy (iv, nonce, 12);
+ iv[12] = 0;
+ iv[13] = 0;
+ iv[14] = 0;
+ iv[15] = 1;
+ }
+ else
+ {
+ grub_memset (iv, 0, sizeof (iv));
+ grub_memcpy (iv, nonce, nonce_len);
+ grub_gcm_mul (iv, h);
+ iv[15] ^= nonce_len * 8;
+ grub_gcm_mul (iv, h);
+ }
+
+ err = grub_crypto_ecb_encrypt (cipher, mac_xor, iv, 16);
+ if (err)
+ return err;
+
+ for (i = 0; i < (psize + 15) / 16; i++)
+ {
+ grub_size_t csize;
+ csize = 16;
+ if (csize > psize - 16 * i)
+ csize = psize - 16 * i;
+ for (j = 0; j < 4; j++)
+ {
+ iv[15 - j]++;
+ if (iv[15 - j] != 0)
+ break;
+ }
+ grub_crypto_xor (mac, mac, in + 16 * i, csize);
+ grub_gcm_mul (mac, h);
+ err = grub_crypto_ecb_encrypt (cipher, mul, iv, 16);
+ if (err)
+ return err;
+ grub_crypto_xor (out + 16 * i, in + 16 * i, mul, csize);
+ }
+ for (j = 0; j < 8; j++)
+ mac[15 - j] ^= ((((grub_uint64_t) psize) * 8) >> (8 * j));
+ grub_gcm_mul (mac, h);
+
+ if (mac_out)
+ grub_crypto_xor (mac_out, mac, mac_xor, m);
+
+ return GPG_ERR_NO_ERROR;
+}
+
+
+static gcry_err_code_t
+algo_decrypt (grub_crypto_cipher_handle_t cipher, grub_uint64_t algo,
+ grub_uint8_t *out, const grub_uint8_t *in,
+ grub_size_t psize,
+ void *mac_out, const void *nonce,
+ unsigned l, unsigned m)
+{
+ switch (algo)
+ {
+ case 0:
+ return grub_ccm_decrypt (cipher, out, in, psize,
+ mac_out, nonce, l, m);
+ case 1:
+ return grub_gcm_decrypt (cipher, out, in, psize,
+ mac_out, nonce,
+ 15 - l, m);
+ default:
+ return GPG_ERR_CIPHER_ALGO;
+ }
+}
+
+static grub_err_t
+grub_zfs_decrypt_real (grub_crypto_cipher_handle_t cipher,
+ grub_uint64_t algo,
+ void *nonce,
+ char *buf, grub_size_t size,
+ const grub_uint32_t *expected_mac,
+ grub_zfs_endian_t endian)
+{
+ grub_uint32_t mac[4];
+ unsigned i;
+ grub_uint32_t sw[4];
+ gcry_err_code_t err;
+
+ grub_memcpy (sw, nonce, 16);
+ if (endian != GRUB_ZFS_BIG_ENDIAN)
+ for (i = 0; i < 4; i++)
+ sw[i] = grub_swap_bytes32 (sw[i]);
+
+ if (!cipher)
+ return grub_error (GRUB_ERR_ACCESS_DENIED,
+ N_("no decryption key available"));
+ err = algo_decrypt (cipher, algo,
+ (grub_uint8_t *) buf,
+ (grub_uint8_t *) buf,
+ size, mac,
+ sw + 1, 3, 12);
+ if (err)
+ return grub_crypto_gcry_error (err);
+
+ for (i = 0; i < 3; i++)
+ if (grub_zfs_to_cpu32 (expected_mac[i], endian)
+ != grub_be_to_cpu32 (mac[i]))
+ return grub_error (GRUB_ERR_BAD_FS, N_("MAC verification failed"));
+ return GRUB_ERR_NONE;
+}
+
+static grub_crypto_cipher_handle_t
+grub_zfs_load_key_real (const struct grub_zfs_key *key,
+ grub_size_t keysize,
+ grub_uint64_t salt,
+ grub_uint64_t algo)
+{
+ unsigned keylen;
+ struct grub_zfs_wrap_key *wrap_key;
+ grub_crypto_cipher_handle_t ret = NULL;
+
+ if (keysize != sizeof (*key))
+ {
+ grub_dprintf ("zfs", "Unexpected key size %" PRIuGRUB_SIZE "\n", keysize);
+ return 0;
+ }
+
+ if (grub_memcmp (key->enc_key + 32, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16)
+ == 0)
+ keylen = 16;
+ else if (grub_memcmp (key->enc_key + 40, "\0\0\0\0\0\0\0\0", 8) == 0)
+ keylen = 24;
+ else
+ keylen = 32;
+
+ for (wrap_key = zfs_wrap_keys; wrap_key; wrap_key = wrap_key->next)
+ {
+ grub_crypto_cipher_handle_t cipher;
+ grub_uint8_t decrypted[32], mac[32], wrap_key_real[32];
+ gcry_err_code_t err;
+ cipher = grub_crypto_cipher_open (GRUB_CIPHER_AES);
+ if (!cipher)
+ {
+ grub_errno = GRUB_ERR_NONE;
+ return 0;
+ }
+ grub_memset (wrap_key_real, 0, sizeof (wrap_key_real));
+ err = 0;
+ if (!wrap_key->is_passphrase)
+ grub_memcpy(wrap_key_real, wrap_key->key,
+ wrap_key->keylen < keylen ? wrap_key->keylen : keylen);
+ else
+ err = grub_crypto_pbkdf2 (GRUB_MD_SHA1,
+ (const grub_uint8_t *) wrap_key->key,
+ wrap_key->keylen,
+ (const grub_uint8_t *) &salt, sizeof (salt),
+ 1000, wrap_key_real, keylen);
+ if (err)
+ {
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+
+ err = grub_crypto_cipher_set_key (cipher, wrap_key_real,
+ keylen);
+ if (err)
+ {
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+
+ err = algo_decrypt (cipher, algo, decrypted, key->unknown_purpose_key, 32,
+ mac, key->unknown_purpose_nonce, 2, 16);
+ if (err || (grub_crypto_memcmp (mac, key->unknown_purpose_key + 32, 16)
+ != 0))
+ {
+ grub_dprintf ("zfs", "key loading failed\n");
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+
+ err = algo_decrypt (cipher, algo, decrypted, key->enc_key, keylen, mac,
+ key->enc_nonce, 2, 16);
+ if (err || grub_crypto_memcmp (mac, key->enc_key + keylen, 16) != 0)
+ {
+ grub_dprintf ("zfs", "key loading failed\n");
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+ ret = grub_crypto_cipher_open (GRUB_CIPHER_AES);
+ if (!ret)
+ {
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+ err = grub_crypto_cipher_set_key (ret, decrypted, keylen);
+ if (err)
+ {
+ grub_errno = GRUB_ERR_NONE;
+ grub_crypto_cipher_close (ret);
+ grub_crypto_cipher_close (cipher);
+ continue;
+ }
+ grub_crypto_cipher_close (cipher);
+ return ret;
+ }
+ return NULL;
+}
+
+static const struct grub_arg_option options[] =
+ {
+ {"raw", 'r', 0, N_("Assume input is raw."), 0, 0},
+ {"hex", 'h', 0, N_("Assume input is hex."), 0, 0},
+ {"passphrase", 'p', 0, N_("Assume input is passphrase."), 0, 0},
+ {0, 0, 0, 0, 0, 0}
+ };
+
+static grub_err_t
+grub_cmd_zfs_key (grub_extcmd_context_t ctxt, int argc, char **args)
+{
+ grub_uint8_t buf[1024];
+ grub_ssize_t real_size;
+
+ if (argc > 0)
+ {
+ grub_file_t file;
+ file = grub_file_open (args[0], GRUB_FILE_TYPE_ZFS_ENCRYPTION_KEY);
+ if (!file)
+ return grub_errno;
+ real_size = grub_file_read (file, buf, 1024);
+ if (real_size < 0)
+ return grub_errno;
+ }
+ else
+ {
+ grub_xputs (_("Enter ZFS password: "));
+ if (!grub_password_get ((char *) buf, 1023))
+ return grub_errno;
+ real_size = grub_strlen ((char *) buf);
+ }
+
+ if (ctxt->state[1].set)
+ {
+ int i;
+ grub_err_t err;
+ for (i = 0; i < real_size / 2; i++)
+ {
+ char c1 = grub_tolower (buf[2 * i]) - '0';
+ char c2 = grub_tolower (buf[2 * i + 1]) - '0';
+ if (c1 > 9)
+ c1 += '0' - 'a' + 10;
+ if (c2 > 9)
+ c2 += '0' - 'a' + 10;
+ buf[i] = (c1 << 4) | c2;
+ }
+ err = grub_zfs_add_key (buf, real_size / 2, 0);
+ if (err)
+ return err;
+ return GRUB_ERR_NONE;
+ }
+
+ return grub_zfs_add_key (buf, real_size,
+ ctxt->state[2].set
+ || (argc == 0 && !ctxt->state[0].set
+ && !ctxt->state[1].set));
+}
+
+static grub_extcmd_t cmd_key;
+
+GRUB_MOD_INIT(zfscrypt)
+{
+ grub_zfs_decrypt = grub_zfs_decrypt_real;
+ grub_zfs_load_key = grub_zfs_load_key_real;
+ cmd_key = grub_register_extcmd ("zfskey", grub_cmd_zfs_key, 0,
+ N_("[-h|-p|-r] [FILE]"),
+ N_("Import ZFS wrapping key stored in FILE."),
+ options);
+}
+
+GRUB_MOD_FINI(zfscrypt)
+{
+ grub_zfs_decrypt = 0;
+ grub_zfs_load_key = 0;
+ grub_unregister_extcmd (cmd_key);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 09:58:53 +0000