[mirror_qemu.git] / crypto / cipher-gcrypt.c

/*
 * QEMU Crypto cipher libgcrypt algorithms
 *
 * Copyright (c) 2015 Red Hat, Inc.
 *
 * This library 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 library; if not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "qemu/osdep.h"
#include "crypto/xts.h"
#include "cipherpriv.h"

#include <gcrypt.h>


bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg,
                             QCryptoCipherMode mode)
{
    switch (alg) {
    case QCRYPTO_CIPHER_ALG_DES_RFB:
    case QCRYPTO_CIPHER_ALG_3DES:
    case QCRYPTO_CIPHER_ALG_AES_128:
    case QCRYPTO_CIPHER_ALG_AES_192:
    case QCRYPTO_CIPHER_ALG_AES_256:
    case QCRYPTO_CIPHER_ALG_CAST5_128:
    case QCRYPTO_CIPHER_ALG_SERPENT_128:
    case QCRYPTO_CIPHER_ALG_SERPENT_192:
    case QCRYPTO_CIPHER_ALG_SERPENT_256:
    case QCRYPTO_CIPHER_ALG_TWOFISH_128:
    case QCRYPTO_CIPHER_ALG_TWOFISH_256:
        break;
    default:
        return false;
    }

    switch (mode) {
    case QCRYPTO_CIPHER_MODE_ECB:
    case QCRYPTO_CIPHER_MODE_CBC:
    case QCRYPTO_CIPHER_MODE_XTS:
    case QCRYPTO_CIPHER_MODE_CTR:
        return true;
    default:
        return false;
    }
}

typedef struct QCryptoCipherGcrypt QCryptoCipherGcrypt;
struct QCryptoCipherGcrypt {
    gcry_cipher_hd_t handle;
    gcry_cipher_hd_t tweakhandle;
    size_t blocksize;
    /* Initialization vector or Counter */
    uint8_t *iv;
};

static void
qcrypto_gcrypt_cipher_free_ctx(QCryptoCipherGcrypt *ctx,
                               QCryptoCipherMode mode)
{
    if (!ctx) {
        return;
    }

    gcry_cipher_close(ctx->handle);
    if (mode == QCRYPTO_CIPHER_MODE_XTS) {
        gcry_cipher_close(ctx->tweakhandle);
    }
    g_free(ctx->iv);
    g_free(ctx);
}


static QCryptoCipherGcrypt *qcrypto_cipher_ctx_new(QCryptoCipherAlgorithm alg,
                                                   QCryptoCipherMode mode,
                                                   const uint8_t *key,
                                                   size_t nkey,
                                                   Error **errp)
{
    QCryptoCipherGcrypt *ctx;
    gcry_error_t err;
    int gcryalg, gcrymode;

    switch (mode) {
    case QCRYPTO_CIPHER_MODE_ECB:
    case QCRYPTO_CIPHER_MODE_XTS:
        gcrymode = GCRY_CIPHER_MODE_ECB;
        break;
    case QCRYPTO_CIPHER_MODE_CBC:
        gcrymode = GCRY_CIPHER_MODE_CBC;
        break;
    case QCRYPTO_CIPHER_MODE_CTR:
        gcrymode = GCRY_CIPHER_MODE_CTR;
        break;
    default:
        error_setg(errp, "Unsupported cipher mode %s",
                   QCryptoCipherMode_str(mode));
        return NULL;
    }

    if (!qcrypto_cipher_validate_key_length(alg, mode, nkey, errp)) {
        return NULL;
    }

    switch (alg) {
    case QCRYPTO_CIPHER_ALG_DES_RFB:
        gcryalg = GCRY_CIPHER_DES;
        break;

    case QCRYPTO_CIPHER_ALG_3DES:
        gcryalg = GCRY_CIPHER_3DES;
        break;

    case QCRYPTO_CIPHER_ALG_AES_128:
        gcryalg = GCRY_CIPHER_AES128;
        break;

    case QCRYPTO_CIPHER_ALG_AES_192:
        gcryalg = GCRY_CIPHER_AES192;
        break;

    case QCRYPTO_CIPHER_ALG_AES_256:
        gcryalg = GCRY_CIPHER_AES256;
        break;

    case QCRYPTO_CIPHER_ALG_CAST5_128:
        gcryalg = GCRY_CIPHER_CAST5;
        break;

    case QCRYPTO_CIPHER_ALG_SERPENT_128:
        gcryalg = GCRY_CIPHER_SERPENT128;
        break;

    case QCRYPTO_CIPHER_ALG_SERPENT_192:
        gcryalg = GCRY_CIPHER_SERPENT192;
        break;

    case QCRYPTO_CIPHER_ALG_SERPENT_256:
        gcryalg = GCRY_CIPHER_SERPENT256;
        break;

    case QCRYPTO_CIPHER_ALG_TWOFISH_128:
        gcryalg = GCRY_CIPHER_TWOFISH128;
        break;

    case QCRYPTO_CIPHER_ALG_TWOFISH_256:
        gcryalg = GCRY_CIPHER_TWOFISH;
        break;

    default:
        error_setg(errp, "Unsupported cipher algorithm %s",
                   QCryptoCipherAlgorithm_str(alg));
        return NULL;
    }

    ctx = g_new0(QCryptoCipherGcrypt, 1);

    err = gcry_cipher_open(&ctx->handle, gcryalg, gcrymode, 0);
    if (err != 0) {
        error_setg(errp, "Cannot initialize cipher: %s",
                   gcry_strerror(err));
        goto error;
    }
    if (mode == QCRYPTO_CIPHER_MODE_XTS) {
        err = gcry_cipher_open(&ctx->tweakhandle, gcryalg, gcrymode, 0);
        if (err != 0) {
            error_setg(errp, "Cannot initialize cipher: %s",
                       gcry_strerror(err));
            goto error;
        }
    }

    if (alg == QCRYPTO_CIPHER_ALG_DES_RFB) {
        /* We're using standard DES cipher from gcrypt, so we need
         * to munge the key so that the results are the same as the
         * bizarre RFB variant of DES :-)
         */
        uint8_t *rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
        err = gcry_cipher_setkey(ctx->handle, rfbkey, nkey);
        g_free(rfbkey);
        ctx->blocksize = 8;
    } else {
        if (mode == QCRYPTO_CIPHER_MODE_XTS) {
            nkey /= 2;
            err = gcry_cipher_setkey(ctx->handle, key, nkey);
            if (err != 0) {
                error_setg(errp, "Cannot set key: %s",
                           gcry_strerror(err));
                goto error;
            }
            err = gcry_cipher_setkey(ctx->tweakhandle, key + nkey, nkey);
        } else {
            err = gcry_cipher_setkey(ctx->handle, key, nkey);
        }
        if (err != 0) {
            error_setg(errp, "Cannot set key: %s",
                       gcry_strerror(err));
            goto error;
        }
        switch (alg) {
        case QCRYPTO_CIPHER_ALG_AES_128:
        case QCRYPTO_CIPHER_ALG_AES_192:
        case QCRYPTO_CIPHER_ALG_AES_256:
        case QCRYPTO_CIPHER_ALG_SERPENT_128:
        case QCRYPTO_CIPHER_ALG_SERPENT_192:
        case QCRYPTO_CIPHER_ALG_SERPENT_256:
        case QCRYPTO_CIPHER_ALG_TWOFISH_128:
        case QCRYPTO_CIPHER_ALG_TWOFISH_256:
            ctx->blocksize = 16;
            break;
        case QCRYPTO_CIPHER_ALG_3DES:
        case QCRYPTO_CIPHER_ALG_CAST5_128:
            ctx->blocksize = 8;
            break;
        default:
            g_assert_not_reached();
        }
    }

    if (mode == QCRYPTO_CIPHER_MODE_XTS) {
        if (ctx->blocksize != XTS_BLOCK_SIZE) {
            error_setg(errp,
                       "Cipher block size %zu must equal XTS block size %d",
                       ctx->blocksize, XTS_BLOCK_SIZE);
            goto error;
        }
        ctx->iv = g_new0(uint8_t, ctx->blocksize);
    }

    return ctx;

 error:
    qcrypto_gcrypt_cipher_free_ctx(ctx, mode);
    return NULL;
}


static void
qcrypto_gcrypt_cipher_ctx_free(QCryptoCipher *cipher)
{
    qcrypto_gcrypt_cipher_free_ctx(cipher->opaque, cipher->mode);
}


static void qcrypto_gcrypt_xts_encrypt(const void *ctx,
                                       size_t length,
                                       uint8_t *dst,
                                       const uint8_t *src)
{
    gcry_error_t err;
    err = gcry_cipher_encrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
    g_assert(err == 0);
}

static void qcrypto_gcrypt_xts_decrypt(const void *ctx,
                                       size_t length,
                                       uint8_t *dst,
                                       const uint8_t *src)
{
    gcry_error_t err;
    err = gcry_cipher_decrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
    g_assert(err == 0);
}

static int
qcrypto_gcrypt_cipher_encrypt(QCryptoCipher *cipher,
                              const void *in,
                              void *out,
                              size_t len,
                              Error **errp)
{
    QCryptoCipherGcrypt *ctx = cipher->opaque;
    gcry_error_t err;

    if (len % ctx->blocksize) {
        error_setg(errp, "Length %zu must be a multiple of block size %zu",
                   len, ctx->blocksize);
        return -1;
    }

    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
        xts_encrypt(ctx->handle, ctx->tweakhandle,
                    qcrypto_gcrypt_xts_encrypt,
                    qcrypto_gcrypt_xts_decrypt,
                    ctx->iv, len, out, in);
    } else {
        err = gcry_cipher_encrypt(ctx->handle,
                                  out, len,
                                  in, len);
        if (err != 0) {
            error_setg(errp, "Cannot encrypt data: %s",
                       gcry_strerror(err));
            return -1;
        }
    }

    return 0;
}


static int
qcrypto_gcrypt_cipher_decrypt(QCryptoCipher *cipher,
                              const void *in,
                              void *out,
                              size_t len,
                              Error **errp)
{
    QCryptoCipherGcrypt *ctx = cipher->opaque;
    gcry_error_t err;

    if (len % ctx->blocksize) {
        error_setg(errp, "Length %zu must be a multiple of block size %zu",
                   len, ctx->blocksize);
        return -1;
    }

    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
        xts_decrypt(ctx->handle, ctx->tweakhandle,
                    qcrypto_gcrypt_xts_encrypt,
                    qcrypto_gcrypt_xts_decrypt,
                    ctx->iv, len, out, in);
    } else {
        err = gcry_cipher_decrypt(ctx->handle,
                                  out, len,
                                  in, len);
        if (err != 0) {
            error_setg(errp, "Cannot decrypt data: %s",
                       gcry_strerror(err));
            return -1;
        }
    }

    return 0;
}

static int
qcrypto_gcrypt_cipher_setiv(QCryptoCipher *cipher,
                            const uint8_t *iv, size_t niv,
                            Error **errp)
{
    QCryptoCipherGcrypt *ctx = cipher->opaque;
    gcry_error_t err;

    if (niv != ctx->blocksize) {
        error_setg(errp, "Expected IV size %zu not %zu",
                   ctx->blocksize, niv);
        return -1;
    }

    if (ctx->iv) {
        memcpy(ctx->iv, iv, niv);
    } else {
        if (cipher->mode == QCRYPTO_CIPHER_MODE_CTR) {
            err = gcry_cipher_setctr(ctx->handle, iv, niv);
            if (err != 0) {
                error_setg(errp, "Cannot set Counter: %s",
                       gcry_strerror(err));
                return -1;
            }
        } else {
            gcry_cipher_reset(ctx->handle);
            err = gcry_cipher_setiv(ctx->handle, iv, niv);
            if (err != 0) {
                error_setg(errp, "Cannot set IV: %s",
                       gcry_strerror(err));
                return -1;
            }
        }
    }

    return 0;
}


static struct QCryptoCipherDriver qcrypto_cipher_lib_driver = {
    .cipher_encrypt = qcrypto_gcrypt_cipher_encrypt,
    .cipher_decrypt = qcrypto_gcrypt_cipher_decrypt,
    .cipher_setiv = qcrypto_gcrypt_cipher_setiv,
    .cipher_free = qcrypto_gcrypt_cipher_ctx_free,
};
Commit	Line	Data
62893b67 DB	1	/*
	2	* QEMU Crypto cipher libgcrypt algorithms
	3	*
	4	* Copyright (c) 2015 Red Hat, Inc.
	5	*
	6	* This library is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; either
b7cbb874	9	* version 2.1 of the License, or (at your option) any later version.
62893b67 DB	10	*
	11	* This library is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
	17	* License along with this library; if not, see <http://www.gnu.org/licenses/>.
	18	*
	19	*/
	20
42f7a448	21	#include "qemu/osdep.h"
eaec903c	22	#include "crypto/xts.h"
75c80078	23	#include "cipherpriv.h"
eaec903c	24
62893b67 DB	25	#include <gcrypt.h>
	26
	27
f844836d GA	28	bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg,
f844836d GA	29	QCryptoCipherMode mode)
62893b67 DB	30	{
	31	switch (alg) {
	32	case QCRYPTO_CIPHER_ALG_DES_RFB:
ffb7bf45	33	case QCRYPTO_CIPHER_ALG_3DES:
62893b67 DB	34	case QCRYPTO_CIPHER_ALG_AES_128:
	35	case QCRYPTO_CIPHER_ALG_AES_192:
	36	case QCRYPTO_CIPHER_ALG_AES_256:
084a85ee	37	case QCRYPTO_CIPHER_ALG_CAST5_128:
94318522 DB	38	case QCRYPTO_CIPHER_ALG_SERPENT_128:
	39	case QCRYPTO_CIPHER_ALG_SERPENT_192:
	40	case QCRYPTO_CIPHER_ALG_SERPENT_256:
50f6753e DB	41	case QCRYPTO_CIPHER_ALG_TWOFISH_128:
50f6753e DB	42	case QCRYPTO_CIPHER_ALG_TWOFISH_256:
f844836d GA	43	break;
	44	default:
	45	return false;
	46	}
	47
	48	switch (mode) {
	49	case QCRYPTO_CIPHER_MODE_ECB:
	50	case QCRYPTO_CIPHER_MODE_CBC:
	51	case QCRYPTO_CIPHER_MODE_XTS:
	52	case QCRYPTO_CIPHER_MODE_CTR:
62893b67 DB	53	return true;
	54	default:
	55	return false;
	56	}
	57	}
	58
3a661f1e DB	59	typedef struct QCryptoCipherGcrypt QCryptoCipherGcrypt;
	60	struct QCryptoCipherGcrypt {
	61	gcry_cipher_hd_t handle;
eaec903c	62	gcry_cipher_hd_t tweakhandle;
3a661f1e	63	size_t blocksize;
3c28292f	64	/* Initialization vector or Counter */
eaec903c	65	uint8_t *iv;
3a661f1e	66	};
62893b67	67
75c80078 LM	68	static void
	69	qcrypto_gcrypt_cipher_free_ctx(QCryptoCipherGcrypt *ctx,
	70	QCryptoCipherMode mode)
cc5eff01 LM	71	{
	72	if (!ctx) {
	73	return;
	74	}
	75
	76	gcry_cipher_close(ctx->handle);
	77	if (mode == QCRYPTO_CIPHER_MODE_XTS) {
	78	gcry_cipher_close(ctx->tweakhandle);
	79	}
	80	g_free(ctx->iv);
	81	g_free(ctx);
	82	}
	83
	84
468fb271 LM	85	static QCryptoCipherGcrypt *qcrypto_cipher_ctx_new(QCryptoCipherAlgorithm alg,
	86	QCryptoCipherMode mode,
	87	const uint8_t *key,
	88	size_t nkey,
	89	Error **errp)
62893b67	90	{
3a661f1e	91	QCryptoCipherGcrypt *ctx;
62893b67 DB	92	gcry_error_t err;
	93	int gcryalg, gcrymode;
	94
	95	switch (mode) {
	96	case QCRYPTO_CIPHER_MODE_ECB:
eaec903c	97	case QCRYPTO_CIPHER_MODE_XTS:
62893b67 DB	98	gcrymode = GCRY_CIPHER_MODE_ECB;
	99	break;
	100	case QCRYPTO_CIPHER_MODE_CBC:
	101	gcrymode = GCRY_CIPHER_MODE_CBC;
	102	break;
3c28292f GA	103	case QCRYPTO_CIPHER_MODE_CTR:
	104	gcrymode = GCRY_CIPHER_MODE_CTR;
	105	break;
62893b67	106	default:
90d6f60d	107	error_setg(errp, "Unsupported cipher mode %s",
977c736f	108	QCryptoCipherMode_str(mode));
62893b67 DB	109	return NULL;
	110	}
	111
eaec903c	112	if (!qcrypto_cipher_validate_key_length(alg, mode, nkey, errp)) {
62893b67 DB	113	return NULL;
	114	}
	115
	116	switch (alg) {
	117	case QCRYPTO_CIPHER_ALG_DES_RFB:
	118	gcryalg = GCRY_CIPHER_DES;
	119	break;
	120
ffb7bf45 LM	121	case QCRYPTO_CIPHER_ALG_3DES:
	122	gcryalg = GCRY_CIPHER_3DES;
	123	break;
	124
62893b67 DB	125	case QCRYPTO_CIPHER_ALG_AES_128:
	126	gcryalg = GCRY_CIPHER_AES128;
	127	break;
	128
	129	case QCRYPTO_CIPHER_ALG_AES_192:
	130	gcryalg = GCRY_CIPHER_AES192;
	131	break;
	132
	133	case QCRYPTO_CIPHER_ALG_AES_256:
	134	gcryalg = GCRY_CIPHER_AES256;
	135	break;
	136
084a85ee DB	137	case QCRYPTO_CIPHER_ALG_CAST5_128:
	138	gcryalg = GCRY_CIPHER_CAST5;
	139	break;
	140
94318522 DB	141	case QCRYPTO_CIPHER_ALG_SERPENT_128:
	142	gcryalg = GCRY_CIPHER_SERPENT128;
	143	break;
	144
	145	case QCRYPTO_CIPHER_ALG_SERPENT_192:
	146	gcryalg = GCRY_CIPHER_SERPENT192;
	147	break;
	148
	149	case QCRYPTO_CIPHER_ALG_SERPENT_256:
	150	gcryalg = GCRY_CIPHER_SERPENT256;
	151	break;
	152
50f6753e DB	153	case QCRYPTO_CIPHER_ALG_TWOFISH_128:
	154	gcryalg = GCRY_CIPHER_TWOFISH128;
	155	break;
	156
	157	case QCRYPTO_CIPHER_ALG_TWOFISH_256:
	158	gcryalg = GCRY_CIPHER_TWOFISH;
	159	break;
	160
62893b67	161	default:
90d6f60d	162	error_setg(errp, "Unsupported cipher algorithm %s",
977c736f	163	QCryptoCipherAlgorithm_str(alg));
62893b67 DB	164	return NULL;
	165	}
	166
3a661f1e DB	167	ctx = g_new0(QCryptoCipherGcrypt, 1);
	168
	169	err = gcry_cipher_open(&ctx->handle, gcryalg, gcrymode, 0);
62893b67 DB	170	if (err != 0) {
	171	error_setg(errp, "Cannot initialize cipher: %s",
	172	gcry_strerror(err));
	173	goto error;
	174	}
468fb271	175	if (mode == QCRYPTO_CIPHER_MODE_XTS) {
eaec903c DB	176	err = gcry_cipher_open(&ctx->tweakhandle, gcryalg, gcrymode, 0);
	177	if (err != 0) {
	178	error_setg(errp, "Cannot initialize cipher: %s",
	179	gcry_strerror(err));
	180	goto error;
	181	}
	182	}
62893b67	183
468fb271	184	if (alg == QCRYPTO_CIPHER_ALG_DES_RFB) {
62893b67 DB	185	/* We're using standard DES cipher from gcrypt, so we need
	186	* to munge the key so that the results are the same as the
	187	* bizarre RFB variant of DES :-)
	188	*/
	189	uint8_t *rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
3a661f1e	190	err = gcry_cipher_setkey(ctx->handle, rfbkey, nkey);
62893b67	191	g_free(rfbkey);
3a661f1e	192	ctx->blocksize = 8;
62893b67	193	} else {
468fb271	194	if (mode == QCRYPTO_CIPHER_MODE_XTS) {
eaec903c DB	195	nkey /= 2;
	196	err = gcry_cipher_setkey(ctx->handle, key, nkey);
	197	if (err != 0) {
	198	error_setg(errp, "Cannot set key: %s",
	199	gcry_strerror(err));
	200	goto error;
	201	}
	202	err = gcry_cipher_setkey(ctx->tweakhandle, key + nkey, nkey);
	203	} else {
	204	err = gcry_cipher_setkey(ctx->handle, key, nkey);
	205	}
	206	if (err != 0) {
	207	error_setg(errp, "Cannot set key: %s",
	208	gcry_strerror(err));
	209	goto error;
	210	}
468fb271	211	switch (alg) {
084a85ee DB	212	case QCRYPTO_CIPHER_ALG_AES_128:
	213	case QCRYPTO_CIPHER_ALG_AES_192:
	214	case QCRYPTO_CIPHER_ALG_AES_256:
94318522 DB	215	case QCRYPTO_CIPHER_ALG_SERPENT_128:
	216	case QCRYPTO_CIPHER_ALG_SERPENT_192:
	217	case QCRYPTO_CIPHER_ALG_SERPENT_256:
50f6753e DB	218	case QCRYPTO_CIPHER_ALG_TWOFISH_128:
50f6753e DB	219	case QCRYPTO_CIPHER_ALG_TWOFISH_256:
084a85ee DB	220	ctx->blocksize = 16;
084a85ee DB	221	break;
ffb7bf45	222	case QCRYPTO_CIPHER_ALG_3DES:
084a85ee DB	223	case QCRYPTO_CIPHER_ALG_CAST5_128:
	224	ctx->blocksize = 8;
	225	break;
	226	default:
	227	g_assert_not_reached();
	228	}
62893b67	229	}
eaec903c	230
468fb271	231	if (mode == QCRYPTO_CIPHER_MODE_XTS) {
a5d2f44d DB	232	if (ctx->blocksize != XTS_BLOCK_SIZE) {
	233	error_setg(errp,
	234	"Cipher block size %zu must equal XTS block size %d",
	235	ctx->blocksize, XTS_BLOCK_SIZE);
	236	goto error;
	237	}
eaec903c	238	ctx->iv = g_new0(uint8_t, ctx->blocksize);
62893b67 DB	239	}
62893b67 DB	240
468fb271	241	return ctx;
62893b67 DB	242
62893b67 DB	243	error:
75c80078	244	qcrypto_gcrypt_cipher_free_ctx(ctx, mode);
62893b67 DB	245	return NULL;
	246	}
	247
	248
75c80078 LM	249	static void
75c80078 LM	250	qcrypto_gcrypt_cipher_ctx_free(QCryptoCipher *cipher)
62893b67	251	{
75c80078	252	qcrypto_gcrypt_cipher_free_ctx(cipher->opaque, cipher->mode);
62893b67 DB	253	}
	254
	255
eaec903c DB	256	static void qcrypto_gcrypt_xts_encrypt(const void *ctx,
	257	size_t length,
	258	uint8_t *dst,
	259	const uint8_t *src)
	260	{
	261	gcry_error_t err;
	262	err = gcry_cipher_encrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
	263	g_assert(err == 0);
	264	}
	265
	266	static void qcrypto_gcrypt_xts_decrypt(const void *ctx,
	267	size_t length,
	268	uint8_t *dst,
	269	const uint8_t *src)
	270	{
	271	gcry_error_t err;
	272	err = gcry_cipher_decrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
	273	g_assert(err == 0);
	274	}
	275
75c80078 LM	276	static int
	277	qcrypto_gcrypt_cipher_encrypt(QCryptoCipher *cipher,
	278	const void *in,
	279	void *out,
	280	size_t len,
	281	Error **errp)
62893b67	282	{
3a661f1e	283	QCryptoCipherGcrypt *ctx = cipher->opaque;
62893b67 DB	284	gcry_error_t err;
62893b67 DB	285
3a661f1e DB	286	if (len % ctx->blocksize) {
	287	error_setg(errp, "Length %zu must be a multiple of block size %zu",
	288	len, ctx->blocksize);
	289	return -1;
	290	}
	291
eaec903c DB	292	if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
	293	xts_encrypt(ctx->handle, ctx->tweakhandle,
	294	qcrypto_gcrypt_xts_encrypt,
	295	qcrypto_gcrypt_xts_decrypt,
	296	ctx->iv, len, out, in);
	297	} else {
	298	err = gcry_cipher_encrypt(ctx->handle,
	299	out, len,
	300	in, len);
	301	if (err != 0) {
	302	error_setg(errp, "Cannot encrypt data: %s",
	303	gcry_strerror(err));
	304	return -1;
	305	}
62893b67 DB	306	}
	307
	308	return 0;
	309	}
	310
	311
75c80078 LM	312	static int
	313	qcrypto_gcrypt_cipher_decrypt(QCryptoCipher *cipher,
	314	const void *in,
	315	void *out,
	316	size_t len,
	317	Error **errp)
62893b67	318	{
3a661f1e	319	QCryptoCipherGcrypt *ctx = cipher->opaque;
62893b67 DB	320	gcry_error_t err;
62893b67 DB	321
3a661f1e DB	322	if (len % ctx->blocksize) {
	323	error_setg(errp, "Length %zu must be a multiple of block size %zu",
	324	len, ctx->blocksize);
	325	return -1;
	326	}
	327
eaec903c DB	328	if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
	329	xts_decrypt(ctx->handle, ctx->tweakhandle,
	330	qcrypto_gcrypt_xts_encrypt,
	331	qcrypto_gcrypt_xts_decrypt,
	332	ctx->iv, len, out, in);
	333	} else {
	334	err = gcry_cipher_decrypt(ctx->handle,
	335	out, len,
	336	in, len);
	337	if (err != 0) {
	338	error_setg(errp, "Cannot decrypt data: %s",
	339	gcry_strerror(err));
	340	return -1;
	341	}
62893b67 DB	342	}
	343
	344	return 0;
	345	}
	346
75c80078 LM	347	static int
	348	qcrypto_gcrypt_cipher_setiv(QCryptoCipher *cipher,
	349	const uint8_t *iv, size_t niv,
	350	Error **errp)
62893b67	351	{
3a661f1e	352	QCryptoCipherGcrypt *ctx = cipher->opaque;
62893b67 DB	353	gcry_error_t err;
62893b67 DB	354
3a661f1e DB	355	if (niv != ctx->blocksize) {
	356	error_setg(errp, "Expected IV size %zu not %zu",
	357	ctx->blocksize, niv);
	358	return -1;
	359	}
	360
eaec903c DB	361	if (ctx->iv) {
	362	memcpy(ctx->iv, iv, niv);
	363	} else {
3c28292f GA	364	if (cipher->mode == QCRYPTO_CIPHER_MODE_CTR) {
	365	err = gcry_cipher_setctr(ctx->handle, iv, niv);
	366	if (err != 0) {
	367	error_setg(errp, "Cannot set Counter: %s",
	368	gcry_strerror(err));
	369	return -1;
	370	}
	371	} else {
	372	gcry_cipher_reset(ctx->handle);
	373	err = gcry_cipher_setiv(ctx->handle, iv, niv);
	374	if (err != 0) {
	375	error_setg(errp, "Cannot set IV: %s",
	376	gcry_strerror(err));
	377	return -1;
	378	}
eaec903c	379	}
62893b67 DB	380	}
	381
	382	return 0;
	383	}
468fb271 LM	384
468fb271 LM	385
75c80078 LM	386	static struct QCryptoCipherDriver qcrypto_cipher_lib_driver = {
	387	.cipher_encrypt = qcrypto_gcrypt_cipher_encrypt,
	388	.cipher_decrypt = qcrypto_gcrypt_cipher_decrypt,
	389	.cipher_setiv = qcrypto_gcrypt_cipher_setiv,
	390	.cipher_free = qcrypto_gcrypt_cipher_ctx_free,
	391	};