[thirdparty/openssl.git] / providers / implementations / ciphers / cipher_aes_xts.c


/*
 * Copyright 2019-2020 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

/*
 * AES low level APIs are deprecated for public use, but still ok for internal
 * use where we're using them to implement the higher level EVP interface, as is
 * the case here.
 */
#include "internal/deprecated.h"

#include "cipher_aes_xts.h"
#include "prov/implementations.h"
#include "prov/providercommon.h"
#include "prov/providercommonerr.h"

/* TODO (3.0) Figure out what flags need to be set */
#define AES_XTS_FLAGS (EVP_CIPH_CUSTOM_IV          \
                       | EVP_CIPH_ALWAYS_CALL_INIT \
                       | EVP_CIPH_CTRL_INIT        \
                       | EVP_CIPH_CUSTOM_COPY)

#define AES_XTS_IV_BITS 128
#define AES_XTS_BLOCK_BITS 8

/* forward declarations */
static OSSL_FUNC_cipher_encrypt_init_fn aes_xts_einit;
static OSSL_FUNC_cipher_decrypt_init_fn aes_xts_dinit;
static OSSL_FUNC_cipher_update_fn aes_xts_stream_update;
static OSSL_FUNC_cipher_final_fn aes_xts_stream_final;
static OSSL_FUNC_cipher_cipher_fn aes_xts_cipher;
static OSSL_FUNC_cipher_freectx_fn aes_xts_freectx;
static OSSL_FUNC_cipher_dupctx_fn aes_xts_dupctx;
static OSSL_FUNC_cipher_set_ctx_params_fn aes_xts_set_ctx_params;
static OSSL_FUNC_cipher_settable_ctx_params_fn aes_xts_settable_ctx_params;

/*
 * Verify that the two keys are different.
 *
 * This addresses the vulnerability described in Rogaway's
 * September 2004 paper:
 *
 *      "Efficient Instantiations of Tweakable Blockciphers and
 *       Refinements to Modes OCB and PMAC".
 *      (http://web.cs.ucdavis.edu/~rogaway/papers/offsets.pdf)
 *
 * FIPS 140-2 IG A.9 XTS-AES Key Generation Requirements states
 * that:
 *      "The check for Key_1 != Key_2 shall be done at any place
 *       BEFORE using the keys in the XTS-AES algorithm to process
 *       data with them."
 */
static int aes_xts_check_keys_differ(const unsigned char *key, size_t bytes,
                                     int enc)
{
    if ((!allow_insecure_decrypt || enc)
            && CRYPTO_memcmp(key, key + bytes, bytes) == 0) {
        ERR_raise(ERR_LIB_PROV, PROV_R_XTS_DUPLICATED_KEYS);
        return 0;
    }
    return 1;
}

/*-
 * Provider dispatch functions
 */
static int aes_xts_init(void *vctx, const unsigned char *key, size_t keylen,
                        const unsigned char *iv, size_t ivlen, int enc)
{
    PROV_AES_XTS_CTX *xctx = (PROV_AES_XTS_CTX *)vctx;
    PROV_CIPHER_CTX *ctx = &xctx->base;

    if (!ossl_prov_is_running())
        return 0;

    ctx->enc = enc;

    if (iv != NULL) {
        if (!cipher_generic_initiv(vctx, iv, ivlen))
            return 0;
    }
    if (key != NULL) {
        if (keylen != ctx->keylen) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
            return 0;
        }
        if (!aes_xts_check_keys_differ(key, keylen / 2, enc))
            return 0;
        return ctx->hw->init(ctx, key, keylen);
    }
    return 1;
}

static int aes_xts_einit(void *vctx, const unsigned char *key, size_t keylen,
                         const unsigned char *iv, size_t ivlen)
{
    return aes_xts_init(vctx, key, keylen, iv, ivlen, 1);
}

static int aes_xts_dinit(void *vctx, const unsigned char *key, size_t keylen,
                         const unsigned char *iv, size_t ivlen)
{
    return aes_xts_init(vctx, key, keylen, iv, ivlen, 0);
}

static void *aes_xts_newctx(void *provctx, unsigned int mode, uint64_t flags,
                            size_t kbits, size_t blkbits, size_t ivbits)
{
    PROV_AES_XTS_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));

    if (ctx != NULL) {
        cipher_generic_initkey(&ctx->base, kbits, blkbits, ivbits, mode, flags,
                               PROV_CIPHER_HW_aes_xts(kbits), NULL);
    }
    return ctx;
}

static void aes_xts_freectx(void *vctx)
{
    PROV_AES_XTS_CTX *ctx = (PROV_AES_XTS_CTX *)vctx;

    cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx);
    OPENSSL_clear_free(ctx,  sizeof(*ctx));
}

static void *aes_xts_dupctx(void *vctx)
{
    PROV_AES_XTS_CTX *in = (PROV_AES_XTS_CTX *)vctx;
    PROV_AES_XTS_CTX *ret = NULL;

    if (!ossl_prov_is_running())
        return NULL;

    if (in->xts.key1 != NULL) {
        if (in->xts.key1 != &in->ks1)
            return NULL;
    }
    if (in->xts.key2 != NULL) {
        if (in->xts.key2 != &in->ks2)
            return NULL;
    }
    ret = OPENSSL_malloc(sizeof(*ret));
    if (ret == NULL) {
        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    in->base.hw->copyctx(&ret->base, &in->base);
    return ret;
}

static int aes_xts_cipher(void *vctx, unsigned char *out, size_t *outl,
                          size_t outsize, const unsigned char *in, size_t inl)
{
    PROV_AES_XTS_CTX *ctx = (PROV_AES_XTS_CTX *)vctx;

    if (!ossl_prov_is_running()
            || ctx->xts.key1 == NULL
            || ctx->xts.key2 == NULL
            || !ctx->base.iv_set
            || out == NULL
            || in == NULL
            || inl < AES_BLOCK_SIZE)
        return 0;

    /*
     * Impose a limit of 2^20 blocks per data unit as specified by
     * IEEE Std 1619-2018.  The earlier and obsolete IEEE Std 1619-2007
     * indicated that this was a SHOULD NOT rather than a MUST NOT.
     * NIST SP 800-38E mandates the same limit.
     */
    if (inl > XTS_MAX_BLOCKS_PER_DATA_UNIT * AES_BLOCK_SIZE) {
        ERR_raise(ERR_LIB_PROV, PROV_R_XTS_DATA_UNIT_IS_TOO_LARGE);
        return 0;
    }

    if (ctx->stream != NULL)
        (*ctx->stream)(in, out, inl, ctx->xts.key1, ctx->xts.key2, ctx->base.iv);
    else if (CRYPTO_xts128_encrypt(&ctx->xts, ctx->base.iv, in, out, inl,
                                   ctx->base.enc))
        return 0;

    *outl = inl;
    return 1;
}

static int aes_xts_stream_update(void *vctx, unsigned char *out, size_t *outl,
                                 size_t outsize, const unsigned char *in,
                                 size_t inl)
{
    PROV_AES_XTS_CTX *ctx = (PROV_AES_XTS_CTX *)vctx;

    if (outsize < inl) {
        ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
        return 0;
    }

    if (!aes_xts_cipher(ctx, out, outl, outsize, in, inl)) {
        ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED);
        return 0;
    }

    return 1;
}

static int aes_xts_stream_final(void *vctx, unsigned char *out, size_t *outl,
                                size_t outsize)
{
    if (!ossl_prov_is_running())
        return 0;
    *outl = 0;
    return 1;
}

static const OSSL_PARAM aes_xts_known_settable_ctx_params[] = {
    OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_KEYLEN, NULL),
    OSSL_PARAM_END
};

static const OSSL_PARAM *aes_xts_settable_ctx_params(ossl_unused void *provctx)
{
    return aes_xts_known_settable_ctx_params;
}

static int aes_xts_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
    const OSSL_PARAM *p;

    /*
     * TODO(3.0) We need a general solution for handling missing parameters
     * inside set_params and get_params methods.
     */
    p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
    if (p != NULL) {
        size_t keylen;

        if (!OSSL_PARAM_get_size_t(p, &keylen)) {
            ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
            return 0;
        }
        /* The key length can not be modified for xts mode */
        if (keylen != ctx->keylen)
            return 0;
    }

    return 1;
}

#define IMPLEMENT_cipher(lcmode, UCMODE, kbits, flags)                         \
static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##lcmode##_get_params;     \
static int aes_##kbits##_##lcmode##_get_params(OSSL_PARAM params[])            \
{                                                                              \
    return cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE,         \
                                     flags, 2 * kbits, AES_XTS_BLOCK_BITS,     \
                                     AES_XTS_IV_BITS);                         \
}                                                                              \
static OSSL_FUNC_cipher_newctx_fn aes_##kbits##_xts_newctx;                    \
static void *aes_##kbits##_xts_newctx(void *provctx)                           \
{                                                                              \
    return aes_xts_newctx(provctx, EVP_CIPH_##UCMODE##_MODE, flags, 2 * kbits, \
                          AES_XTS_BLOCK_BITS, AES_XTS_IV_BITS);                \
}                                                                              \
const OSSL_DISPATCH ossl_aes##kbits##xts_functions[] = {                       \
    { OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))aes_##kbits##_xts_newctx },     \
    { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_xts_einit },          \
    { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_xts_dinit },          \
    { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_xts_stream_update },        \
    { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_xts_stream_final },          \
    { OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))aes_xts_cipher },               \
    { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_xts_freectx },             \
    { OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_xts_dupctx },               \
    { OSSL_FUNC_CIPHER_GET_PARAMS,                                             \
      (void (*)(void))aes_##kbits##_##lcmode##_get_params },                   \
    { OSSL_FUNC_CIPHER_GETTABLE_PARAMS,                                        \
      (void (*)(void))cipher_generic_gettable_params },                        \
    { OSSL_FUNC_CIPHER_GET_CTX_PARAMS,                                         \
      (void (*)(void))cipher_generic_get_ctx_params },                         \
    { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS,                                    \
      (void (*)(void))cipher_generic_gettable_ctx_params },                    \
    { OSSL_FUNC_CIPHER_SET_CTX_PARAMS,                                         \
      (void (*)(void))aes_xts_set_ctx_params },                                \
    { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS,                                    \
     (void (*)(void))aes_xts_settable_ctx_params },                            \
    { 0, NULL }                                                                \
}

IMPLEMENT_cipher(xts, XTS, 256, AES_XTS_FLAGS);
IMPLEMENT_cipher(xts, XTS, 128, AES_XTS_FLAGS);
Commit	Line	Data
1be63951	1
3a9f26f3	2	/*
33388b44	3	* Copyright 2019-2020 The OpenSSL Project Authors. All Rights Reserved.
3a9f26f3 SL	4	*
	5	* Licensed under the Apache License 2.0 (the "License"). You may not use
	6	* this file except in compliance with the License. You can obtain a copy
	7	* in the file LICENSE in the source distribution or at
	8	* https://www.openssl.org/source/license.html
	9	*/
	10
c72fa255 MC	11	/*
	12	* AES low level APIs are deprecated for public use, but still ok for internal
	13	* use where we're using them to implement the higher level EVP interface, as is
	14	* the case here.
	15	*/
	16	#include "internal/deprecated.h"
	17
3a9f26f3	18	#include "cipher_aes_xts.h"
af3e7e1b	19	#include "prov/implementations.h"
f99d3eed	20	#include "prov/providercommon.h"
ddd21319	21	#include "prov/providercommonerr.h"
3a9f26f3 SL	22
3a9f26f3 SL	23	/* TODO (3.0) Figure out what flags need to be set */
6ef81d38 RL	24	#define AES_XTS_FLAGS (EVP_CIPH_CUSTOM_IV \
	25	\| EVP_CIPH_ALWAYS_CALL_INIT \
	26	\| EVP_CIPH_CTRL_INIT \
3a9f26f3 SL	27	\| EVP_CIPH_CUSTOM_COPY)
	28
	29	#define AES_XTS_IV_BITS 128
	30	#define AES_XTS_BLOCK_BITS 8
	31
3a9f26f3	32	/* forward declarations */
363b1e5d DMSP	33	static OSSL_FUNC_cipher_encrypt_init_fn aes_xts_einit;
	34	static OSSL_FUNC_cipher_decrypt_init_fn aes_xts_dinit;
	35	static OSSL_FUNC_cipher_update_fn aes_xts_stream_update;
	36	static OSSL_FUNC_cipher_final_fn aes_xts_stream_final;
	37	static OSSL_FUNC_cipher_cipher_fn aes_xts_cipher;
	38	static OSSL_FUNC_cipher_freectx_fn aes_xts_freectx;
	39	static OSSL_FUNC_cipher_dupctx_fn aes_xts_dupctx;
	40	static OSSL_FUNC_cipher_set_ctx_params_fn aes_xts_set_ctx_params;
	41	static OSSL_FUNC_cipher_settable_ctx_params_fn aes_xts_settable_ctx_params;
3a9f26f3 SL	42
	43	/*
	44	* Verify that the two keys are different.
	45	*
	46	* This addresses the vulnerability described in Rogaway's
	47	* September 2004 paper:
	48	*
	49	* "Efficient Instantiations of Tweakable Blockciphers and
	50	* Refinements to Modes OCB and PMAC".
	51	* (http://web.cs.ucdavis.edu/~rogaway/papers/offsets.pdf)
	52	*
	53	* FIPS 140-2 IG A.9 XTS-AES Key Generation Requirements states
	54	* that:
	55	* "The check for Key_1 != Key_2 shall be done at any place
	56	* BEFORE using the keys in the XTS-AES algorithm to process
	57	* data with them."
	58	*/
	59	static int aes_xts_check_keys_differ(const unsigned char *key, size_t bytes,
	60	int enc)
	61	{
	62	if ((!allow_insecure_decrypt \|\| enc)
	63	&& CRYPTO_memcmp(key, key + bytes, bytes) == 0) {
	64	ERR_raise(ERR_LIB_PROV, PROV_R_XTS_DUPLICATED_KEYS);
	65	return 0;
	66	}
	67	return 1;
	68	}
	69
	70	/*-
	71	* Provider dispatch functions
	72	*/
	73	static int aes_xts_init(void vctx, const unsigned char key, size_t keylen,
	74	const unsigned char *iv, size_t ivlen, int enc)
	75	{
	76	PROV_AES_XTS_CTX xctx = (PROV_AES_XTS_CTX )vctx;
	77	PROV_CIPHER_CTX *ctx = &xctx->base;
	78
f99d3eed P	79	if (!ossl_prov_is_running())
	80	return 0;
	81
3a9f26f3 SL	82	ctx->enc = enc;
	83
	84	if (iv != NULL) {
089cb623	85	if (!cipher_generic_initiv(vctx, iv, ivlen))
3a9f26f3	86	return 0;
3a9f26f3 SL	87	}
	88	if (key != NULL) {
	89	if (keylen != ctx->keylen) {
	90	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
	91	return 0;
	92	}
	93	if (!aes_xts_check_keys_differ(key, keylen / 2, enc))
	94	return 0;
	95	return ctx->hw->init(ctx, key, keylen);
	96	}
	97	return 1;
	98	}
	99
	100	static int aes_xts_einit(void vctx, const unsigned char key, size_t keylen,
	101	const unsigned char *iv, size_t ivlen)
	102	{
	103	return aes_xts_init(vctx, key, keylen, iv, ivlen, 1);
	104	}
	105
	106	static int aes_xts_dinit(void vctx, const unsigned char key, size_t keylen,
	107	const unsigned char *iv, size_t ivlen)
	108	{
	109	return aes_xts_init(vctx, key, keylen, iv, ivlen, 0);
	110	}
	111
55c7dc79 SL	112	static void aes_xts_newctx(void provctx, unsigned int mode, uint64_t flags,
55c7dc79 SL	113	size_t kbits, size_t blkbits, size_t ivbits)
3a9f26f3 SL	114	{
	115	PROV_AES_XTS_CTX ctx = OPENSSL_zalloc(sizeof(ctx));
	116
	117	if (ctx != NULL) {
55c7dc79	118	cipher_generic_initkey(&ctx->base, kbits, blkbits, ivbits, mode, flags,
3a9f26f3 SL	119	PROV_CIPHER_HW_aes_xts(kbits), NULL);
	120	}
	121	return ctx;
	122	}
	123
	124	static void aes_xts_freectx(void *vctx)
	125	{
	126	PROV_AES_XTS_CTX ctx = (PROV_AES_XTS_CTX )vctx;
	127
63ee6ec1	128	cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx);
3a9f26f3 SL	129	OPENSSL_clear_free(ctx, sizeof(*ctx));
	130	}
	131
	132	static void aes_xts_dupctx(void vctx)
	133	{
	134	PROV_AES_XTS_CTX in = (PROV_AES_XTS_CTX )vctx;
	135	PROV_AES_XTS_CTX *ret = NULL;
	136
f99d3eed P	137	if (!ossl_prov_is_running())
	138	return NULL;
	139
3a9f26f3 SL	140	if (in->xts.key1 != NULL) {
	141	if (in->xts.key1 != &in->ks1)
	142	return NULL;
	143	}
	144	if (in->xts.key2 != NULL) {
	145	if (in->xts.key2 != &in->ks2)
	146	return NULL;
	147	}
	148	ret = OPENSSL_malloc(sizeof(*ret));
	149	if (ret == NULL) {
	150	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
	151	return NULL;
	152	}
f75abcc0	153	in->base.hw->copyctx(&ret->base, &in->base);
3a9f26f3 SL	154	return ret;
	155	}
	156
	157	static int aes_xts_cipher(void vctx, unsigned char out, size_t *outl,
	158	size_t outsize, const unsigned char *in, size_t inl)
	159	{
	160	PROV_AES_XTS_CTX ctx = (PROV_AES_XTS_CTX )vctx;
	161
f99d3eed P	162	if (!ossl_prov_is_running()
f99d3eed P	163	\|\| ctx->xts.key1 == NULL
3a9f26f3	164	\|\| ctx->xts.key2 == NULL
089cb623	165	\|\| !ctx->base.iv_set
3a9f26f3 SL	166	\|\| out == NULL
	167	\|\| in == NULL
	168	\|\| inl < AES_BLOCK_SIZE)
	169	return 0;
	170
	171	/*
79c44b4e	172	* Impose a limit of 2^20 blocks per data unit as specified by
3a9f26f3 SL	173	* IEEE Std 1619-2018. The earlier and obsolete IEEE Std 1619-2007
	174	* indicated that this was a SHOULD NOT rather than a MUST NOT.
	175	* NIST SP 800-38E mandates the same limit.
	176	*/
	177	if (inl > XTS_MAX_BLOCKS_PER_DATA_UNIT * AES_BLOCK_SIZE) {
	178	ERR_raise(ERR_LIB_PROV, PROV_R_XTS_DATA_UNIT_IS_TOO_LARGE);
	179	return 0;
	180	}
	181
	182	if (ctx->stream != NULL)
	183	(*ctx->stream)(in, out, inl, ctx->xts.key1, ctx->xts.key2, ctx->base.iv);
	184	else if (CRYPTO_xts128_encrypt(&ctx->xts, ctx->base.iv, in, out, inl,
	185	ctx->base.enc))
	186	return 0;
3a9f26f3 SL	187
	188	*outl = inl;
	189	return 1;
	190	}
	191
	192	static int aes_xts_stream_update(void vctx, unsigned char out, size_t *outl,
	193	size_t outsize, const unsigned char *in,
	194	size_t inl)
	195	{
	196	PROV_AES_XTS_CTX ctx = (PROV_AES_XTS_CTX )vctx;
	197
	198	if (outsize < inl) {
	199	ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
	200	return 0;
	201	}
	202
	203	if (!aes_xts_cipher(ctx, out, outl, outsize, in, inl)) {
	204	ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED);
	205	return 0;
	206	}
	207
3a9f26f3 SL	208	return 1;
	209	}
	210
	211	static int aes_xts_stream_final(void vctx, unsigned char out, size_t *outl,
	212	size_t outsize)
	213	{
f99d3eed P	214	if (!ossl_prov_is_running())
f99d3eed P	215	return 0;
3a9f26f3 SL	216	*outl = 0;
	217	return 1;
	218	}
	219
	220	static const OSSL_PARAM aes_xts_known_settable_ctx_params[] = {
	221	OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_KEYLEN, NULL),
	222	OSSL_PARAM_END
	223	};
	224
1017ab21	225	static const OSSL_PARAM aes_xts_settable_ctx_params(ossl_unused void provctx)
3a9f26f3 SL	226	{
	227	return aes_xts_known_settable_ctx_params;
	228	}
	229
	230	static int aes_xts_set_ctx_params(void *vctx, const OSSL_PARAM params[])
	231	{
	232	PROV_CIPHER_CTX ctx = (PROV_CIPHER_CTX )vctx;
	233	const OSSL_PARAM *p;
	234
	235	/*
	236	* TODO(3.0) We need a general solution for handling missing parameters
	237	* inside set_params and get_params methods.
	238	*/
	239	p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
	240	if (p != NULL) {
	241	size_t keylen;
	242
	243	if (!OSSL_PARAM_get_size_t(p, &keylen)) {
	244	ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
	245	return 0;
	246	}
	247	/* The key length can not be modified for xts mode */
	248	if (keylen != ctx->keylen)
	249	return 0;
	250	}
	251
	252	return 1;
	253	}
	254
	255	#define IMPLEMENT_cipher(lcmode, UCMODE, kbits, flags) \
363b1e5d	256	static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##lcmode##_get_params; \
3a9f26f3 SL	257	static int aes_##kbits##_##lcmode##_get_params(OSSL_PARAM params[]) \
	258	{ \
	259	return cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE, \
	260	flags, 2 * kbits, AES_XTS_BLOCK_BITS, \
	261	AES_XTS_IV_BITS); \
	262	} \
363b1e5d	263	static OSSL_FUNC_cipher_newctx_fn aes_##kbits##_xts_newctx; \
3a9f26f3 SL	264	static void aes_##kbits##_xts_newctx(void provctx) \
3a9f26f3 SL	265	{ \
55c7dc79	266	return aes_xts_newctx(provctx, EVP_CIPH_##UCMODE##_MODE, flags, 2 * kbits, \
3a9f26f3 SL	267	AES_XTS_BLOCK_BITS, AES_XTS_IV_BITS); \
3a9f26f3 SL	268	} \
1be63951	269	const OSSL_DISPATCH ossl_aes##kbits##xts_functions[] = { \
3a9f26f3 SL	270	{ OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))aes_##kbits##_xts_newctx }, \
	271	{ OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_xts_einit }, \
	272	{ OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_xts_dinit }, \
	273	{ OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_xts_stream_update }, \
	274	{ OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_xts_stream_final }, \
	275	{ OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))aes_xts_cipher }, \
	276	{ OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_xts_freectx }, \
	277	{ OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_xts_dupctx }, \
	278	{ OSSL_FUNC_CIPHER_GET_PARAMS, \
	279	(void (*)(void))aes_##kbits##_##lcmode##_get_params }, \
	280	{ OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \
	281	(void (*)(void))cipher_generic_gettable_params }, \
	282	{ OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \
	283	(void (*)(void))cipher_generic_get_ctx_params }, \
	284	{ OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \
	285	(void (*)(void))cipher_generic_gettable_ctx_params }, \
	286	{ OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \
	287	(void (*)(void))aes_xts_set_ctx_params }, \
	288	{ OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \
	289	(void (*)(void))aes_xts_settable_ctx_params }, \
	290	{ 0, NULL } \
	291	}
	292
	293	IMPLEMENT_cipher(xts, XTS, 256, AES_XTS_FLAGS);
	294	IMPLEMENT_cipher(xts, XTS, 128, AES_XTS_FLAGS);