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-rw-r--r--lib/nettle/backport/xts.c273
1 files changed, 0 insertions, 273 deletions
diff --git a/lib/nettle/backport/xts.c b/lib/nettle/backport/xts.c
deleted file mode 100644
index d8c258f650..0000000000
--- a/lib/nettle/backport/xts.c
+++ /dev/null
@@ -1,273 +0,0 @@
-/*
- * Copyright (C) 2018 Red Hat, Inc.
- *
- * Author: Simo Sorce
- *
- * This file is part of GnuTLS.
- *
- * The GnuTLS is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public License
- * as published by the Free Software Foundation; either version 2.1 of
- * the License, or (at your option) any later version.
- *
- * This library 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>
- *
- */
-
-/* #############################################
- * THIS IS A BACKPORT FROM NETTLE, DO NOT MODIFY
- * #############################################
- */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#ifndef HAVE_NETTLE_XTS_ENCRYPT_MESSAGE
-#include "xts.h"
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <nettle/macros.h>
-#include <nettle/memxor.h>
-
-/* An aligned 16-byte block. */
-union _backport_nettle_block16
-{
- uint8_t b[16];
- unsigned long w[16 / sizeof(unsigned long)];
- uint64_t u64[2];
-};
-
-/* shift left one and XOR with 0x87 if there is carry. */
-/* the algorithm reads this as a 128bit Little Endian number */
-/* src and dest can point to the same buffer for in-place operations */
-#if WORDS_BIGENDIAN
-#define BE_SHIFT(x) ((((x) & 0x7f7f7f7f7f7f7f7f) << 1) | \
- (((x) & 0x8080808080808080) >> 15))
-static void
-xts_shift(union _backport_nettle_block16 *dst,
- const union _backport_nettle_block16 *src)
-{
- uint64_t carry = (src->u64[1] & 0x80) >> 7;
- dst->u64[1] = BE_SHIFT(src->u64[1]) | ((src->u64[0] & 0x80) << 49);
- dst->u64[0] = BE_SHIFT(src->u64[0]);
- dst->u64[0] ^= 0x8700000000000000 & -carry;
-}
-#else /* !WORDS_BIGENDIAN */
-static void
-xts_shift(union _backport_nettle_block16 *dst,
- const union _backport_nettle_block16 *src)
-{
- uint64_t carry = src->u64[1] >> 63;
- dst->u64[1] = (src->u64[1] << 1) | (src->u64[0] >> 63);
- dst->u64[0] = src->u64[0] << 1;
- dst->u64[0] ^= 0x87 & -carry;
-}
-#endif /* !WORDS_BIGNDIAN */
-
-static void
-check_length(size_t length, uint8_t *dst)
-{
- assert(length >= XTS_BLOCK_SIZE);
- /* asserts may be compiled out, try to save the user by zeroing the dst in
- * case the buffer contains sensitive data (like the clear text for inplace
- * encryption) */
- if (length < XTS_BLOCK_SIZE)
- memset(dst, '\0', length);
-}
-
-/* works also for inplace encryption/decryption */
-
-void
-xts_encrypt_message(const void *enc_ctx, const void *twk_ctx,
- nettle_cipher_func *encf,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- union _backport_nettle_block16 T;
- union _backport_nettle_block16 P;
-
- check_length(length, dst);
-
- encf(twk_ctx, XTS_BLOCK_SIZE, T.b, tweak);
-
- /* the zeroth power of alpha is the initial ciphertext value itself, so we
- * skip shifting and do it at the end of each block operation instead */
- for (;length >= 2 * XTS_BLOCK_SIZE || length == XTS_BLOCK_SIZE;
- length -= XTS_BLOCK_SIZE, src += XTS_BLOCK_SIZE, dst += XTS_BLOCK_SIZE)
- {
- memxor3(P.b, src, T.b, XTS_BLOCK_SIZE); /* P -> PP */
- encf(enc_ctx, XTS_BLOCK_SIZE, dst, P.b); /* CC */
- memxor(dst, T.b, XTS_BLOCK_SIZE); /* CC -> C */
-
- /* shift T for next block if any */
- if (length > XTS_BLOCK_SIZE)
- xts_shift(&T, &T);
- }
-
- /* if the last block is partial, handle via stealing */
- if (length)
- {
- /* S Holds the real C(n-1) (Whole last block to steal from) */
- union _backport_nettle_block16 S;
-
- memxor3(P.b, src, T.b, XTS_BLOCK_SIZE); /* P -> PP */
- encf(enc_ctx, XTS_BLOCK_SIZE, S.b, P.b); /* CC */
- memxor(S.b, T.b, XTS_BLOCK_SIZE); /* CC -> S */
-
- /* shift T for next block */
- xts_shift(&T, &T);
-
- length -= XTS_BLOCK_SIZE;
- src += XTS_BLOCK_SIZE;
-
- memxor3(P.b, src, T.b, length); /* P |.. */
- /* steal ciphertext to complete block */
- memxor3(P.b + length, S.b + length, T.b + length,
- XTS_BLOCK_SIZE - length); /* ..| S_2 -> PP */
-
- encf(enc_ctx, XTS_BLOCK_SIZE, dst, P.b); /* CC */
- memxor(dst, T.b, XTS_BLOCK_SIZE); /* CC -> C(n-1) */
-
- /* Do this after we read src so inplace operations do not break */
- dst += XTS_BLOCK_SIZE;
- memcpy(dst, S.b, length); /* S_1 -> C(n) */
- }
-}
-
-void
-xts_decrypt_message(const void *dec_ctx, const void *twk_ctx,
- nettle_cipher_func *decf, nettle_cipher_func *encf,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- union _backport_nettle_block16 T;
- union _backport_nettle_block16 C;
-
- check_length(length, dst);
-
- encf(twk_ctx, XTS_BLOCK_SIZE, T.b, tweak);
-
- for (;length >= 2 * XTS_BLOCK_SIZE || length == XTS_BLOCK_SIZE;
- length -= XTS_BLOCK_SIZE, src += XTS_BLOCK_SIZE, dst += XTS_BLOCK_SIZE)
- {
- memxor3(C.b, src, T.b, XTS_BLOCK_SIZE); /* c -> CC */
- decf(dec_ctx, XTS_BLOCK_SIZE, dst, C.b); /* PP */
- memxor(dst, T.b, XTS_BLOCK_SIZE); /* PP -> P */
-
- /* shift T for next block if any */
- if (length > XTS_BLOCK_SIZE)
- xts_shift(&T, &T);
- }
-
- /* if the last block is partial, handle via stealing */
- if (length)
- {
- union _backport_nettle_block16 T1;
- /* S Holds the real P(n) (with part of stolen ciphertext) */
- union _backport_nettle_block16 S;
-
- /* we need the last T(n) and save the T(n-1) for later */
- xts_shift(&T1, &T);
-
- memxor3(C.b, src, T1.b, XTS_BLOCK_SIZE); /* C -> CC */
- decf(dec_ctx, XTS_BLOCK_SIZE, S.b, C.b); /* PP */
- memxor(S.b, T1.b, XTS_BLOCK_SIZE); /* PP -> S */
-
- /* process next block (Pn-1) */
- length -= XTS_BLOCK_SIZE;
- src += XTS_BLOCK_SIZE;
-
- /* Prepare C, P holds the real P(n) */
- memxor3(C.b, src, T.b, length); /* C_1 |.. */
- memxor3(C.b + length, S.b + length, T.b + length,
- XTS_BLOCK_SIZE - length); /* ..| S_2 -> CC */
- decf(dec_ctx, XTS_BLOCK_SIZE, dst, C.b); /* PP */
- memxor(dst, T.b, XTS_BLOCK_SIZE); /* PP -> P(n-1) */
-
- /* Do this after we read src so inplace operations do not break */
- dst += XTS_BLOCK_SIZE;
- memcpy(dst, S.b, length); /* S_1 -> P(n) */
- }
-}
-
-void
-xts_aes128_set_encrypt_key(struct xts_aes128_key *xts_key, const uint8_t *key)
-{
- aes128_set_encrypt_key(&xts_key->cipher, key);
- aes128_set_encrypt_key(&xts_key->tweak_cipher, &key[AES128_KEY_SIZE]);
-}
-
-void
-xts_aes128_set_decrypt_key(struct xts_aes128_key *xts_key, const uint8_t *key)
-{
- aes128_set_decrypt_key(&xts_key->cipher, key);
- aes128_set_encrypt_key(&xts_key->tweak_cipher, &key[AES128_KEY_SIZE]);
-}
-
-void
-xts_aes128_encrypt_message(struct xts_aes128_key *xts_key,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- xts_encrypt_message(&xts_key->cipher, &xts_key->tweak_cipher,
- (nettle_cipher_func *) aes128_encrypt,
- tweak, length, dst, src);
-}
-
-void
-xts_aes128_decrypt_message(struct xts_aes128_key *xts_key,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- xts_decrypt_message(&xts_key->cipher, &xts_key->tweak_cipher,
- (nettle_cipher_func *) aes128_decrypt,
- (nettle_cipher_func *) aes128_encrypt,
- tweak, length, dst, src);
-}
-
-void
-xts_aes256_set_encrypt_key(struct xts_aes256_key *xts_key, const uint8_t *key)
-{
- aes256_set_encrypt_key(&xts_key->cipher, key);
- aes256_set_encrypt_key(&xts_key->tweak_cipher, &key[AES256_KEY_SIZE]);
-}
-
-void
-xts_aes256_set_decrypt_key(struct xts_aes256_key *xts_key, const uint8_t *key)
-{
- aes256_set_decrypt_key(&xts_key->cipher, key);
- aes256_set_encrypt_key(&xts_key->tweak_cipher, &key[AES256_KEY_SIZE]);
-}
-
-void
-xts_aes256_encrypt_message(struct xts_aes256_key *xts_key,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- xts_encrypt_message(&xts_key->cipher, &xts_key->tweak_cipher,
- (nettle_cipher_func *) aes256_encrypt,
- tweak, length, dst, src);
-}
-
-void
-xts_aes256_decrypt_message(struct xts_aes256_key *xts_key,
- const uint8_t *tweak, size_t length,
- uint8_t *dst, const uint8_t *src)
-{
- xts_decrypt_message(&xts_key->cipher, &xts_key->tweak_cipher,
- (nettle_cipher_func *) aes256_decrypt,
- (nettle_cipher_func *) aes256_encrypt,
- tweak, length, dst, src);
-}
-
-#endif /* HAVE_NETTLE_XTS_ENCRYPT_MESSAGE */
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