/*      $OpenBSD: xform.c,v 1.61 2021/10/22 12:30:53 bluhm Exp $        */
/*
 * The authors of this code are John Ioannidis (ji@tla.org),
 * Angelos D. Keromytis (kermit@csd.uch.gr),
 * Niels Provos (provos@physnet.uni-hamburg.de),
 * Damien Miller (djm@mindrot.org) and
 * Mike Belopuhov (mikeb@openbsd.org).
 *
 * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
 * in November 1995.
 *
 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
 * by Angelos D. Keromytis.
 *
 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
 * and Niels Provos.
 *
 * Additional features in 1999 by Angelos D. Keromytis.
 *
 * AES XTS implementation in 2008 by Damien Miller
 *
 * AES-GCM-16 and Chacha20-Poly1305 AEAD modes by Mike Belopuhov.
 *
 * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
 * Angelos D. Keromytis and Niels Provos.
 *
 * Copyright (C) 2001, Angelos D. Keromytis.
 *
 * Copyright (C) 2008, Damien Miller
 *
 * Copyright (C) 2010, 2015, Mike Belopuhov
 *
 * Permission to use, copy, and modify this software with or without fee
 * is hereby granted, provided that this entire notice is included in
 * all copies of any software which is or includes a copy or
 * modification of this software.
 * You may use this code under the GNU public license if you so wish. Please
 * contribute changes back to the authors under this freer than GPL license
 * so that we may further the use of strong encryption without limitations to
 * all.
 *
 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
 * PURPOSE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <machine/cpu.h>

#include <crypto/md5.h>
#include <crypto/sha1.h>
#include <crypto/sha2.h>
#include <crypto/rmd160.h>
#include <crypto/blf.h>
#include <crypto/cast.h>
#include <crypto/rijndael.h>
#include <crypto/aes.h>
#include <crypto/cryptodev.h>
#include <crypto/xform.h>
#include <crypto/gmac.h>
#include <crypto/chachapoly.h>

extern void des_ecb3_encrypt(caddr_t, caddr_t, caddr_t, caddr_t, caddr_t, int);

int  des_set_key(void *, caddr_t);
int  des3_setkey(void *, u_int8_t *, int);
int  blf_setkey(void *, u_int8_t *, int);
int  cast5_setkey(void *, u_int8_t *, int);
int  aes_setkey(void *, u_int8_t *, int);
int  aes_ctr_setkey(void *, u_int8_t *, int);
int  aes_xts_setkey(void *, u_int8_t *, int);
int  null_setkey(void *, u_int8_t *, int);

void des3_encrypt(caddr_t, u_int8_t *);
void blf_encrypt(caddr_t, u_int8_t *);
void cast5_encrypt(caddr_t, u_int8_t *);
void aes_encrypt(caddr_t, u_int8_t *);
void null_encrypt(caddr_t, u_int8_t *);
void aes_xts_encrypt(caddr_t, u_int8_t *);

void des3_decrypt(caddr_t, u_int8_t *);
void blf_decrypt(caddr_t, u_int8_t *);
void cast5_decrypt(caddr_t, u_int8_t *);
void aes_decrypt(caddr_t, u_int8_t *);
void null_decrypt(caddr_t, u_int8_t *);
void aes_xts_decrypt(caddr_t, u_int8_t *);

void aes_ctr_crypt(caddr_t, u_int8_t *);

void aes_ctr_reinit(caddr_t, u_int8_t *);
void aes_xts_reinit(caddr_t, u_int8_t *);
void aes_gcm_reinit(caddr_t, u_int8_t *);

int MD5Update_int(void *, const u_int8_t *, u_int16_t);
int SHA1Update_int(void *, const u_int8_t *, u_int16_t);
int RMD160Update_int(void *, const u_int8_t *, u_int16_t);
int SHA256Update_int(void *, const u_int8_t *, u_int16_t);
int SHA384Update_int(void *, const u_int8_t *, u_int16_t);
int SHA512Update_int(void *, const u_int8_t *, u_int16_t);

u_int32_t deflate_compress(u_int8_t *, u_int32_t, u_int8_t **);
u_int32_t deflate_decompress(u_int8_t *, u_int32_t, u_int8_t **);

struct aes_ctr_ctx {
        AES_CTX         ac_key;
        u_int8_t        ac_block[AESCTR_BLOCKSIZE];
};

struct aes_xts_ctx {
        rijndael_ctx key1;
        rijndael_ctx key2;
        u_int8_t tweak[AES_XTS_BLOCKSIZE];
};

/* Helper */
void aes_xts_crypt(struct aes_xts_ctx *, u_int8_t *, u_int);

/* Encryption instances */
const struct enc_xform enc_xform_3des = {
        CRYPTO_3DES_CBC, "3DES",
        8, 8, 24, 24, 384,
        des3_encrypt,
        des3_decrypt,
        des3_setkey,
        NULL
};

const struct enc_xform enc_xform_blf = {
        CRYPTO_BLF_CBC, "Blowfish",
        8, 8, 5, 56 /* 448 bits, max key */,
        sizeof(blf_ctx),
        blf_encrypt,
        blf_decrypt,
        blf_setkey,
        NULL
};

const struct enc_xform enc_xform_cast5 = {
        CRYPTO_CAST_CBC, "CAST-128",
        8, 8, 5, 16,
        sizeof(cast_key),
        cast5_encrypt,
        cast5_decrypt,
        cast5_setkey,
        NULL
};

const struct enc_xform enc_xform_aes = {
        CRYPTO_AES_CBC, "AES",
        16, 16, 16, 32,
        sizeof(AES_CTX),
        aes_encrypt,
        aes_decrypt,
        aes_setkey,
        NULL
};

const struct enc_xform enc_xform_aes_ctr = {
        CRYPTO_AES_CTR, "AES-CTR",
        16, 8, 16+4, 32+4,
        sizeof(struct aes_ctr_ctx),
        aes_ctr_crypt,
        aes_ctr_crypt,
        aes_ctr_setkey,
        aes_ctr_reinit
};

const struct enc_xform enc_xform_aes_gcm = {
        CRYPTO_AES_GCM_16, "AES-GCM",
        1, 8, 16+4, 32+4,
        sizeof(struct aes_ctr_ctx),
        aes_ctr_crypt,
        aes_ctr_crypt,
        aes_ctr_setkey,
        aes_gcm_reinit
};

const struct enc_xform enc_xform_aes_gmac = {
        CRYPTO_AES_GMAC, "AES-GMAC",
        1, 8, 16+4, 32+4, 0,
        NULL,
        NULL,
        NULL,
        NULL
};

const struct enc_xform enc_xform_aes_xts = {
        CRYPTO_AES_XTS, "AES-XTS",
        16, 8, 32, 64,
        sizeof(struct aes_xts_ctx),
        aes_xts_encrypt,
        aes_xts_decrypt,
        aes_xts_setkey,
        aes_xts_reinit
};

const struct enc_xform enc_xform_chacha20_poly1305 = {
        CRYPTO_CHACHA20_POLY1305, "CHACHA20-POLY1305",
        1, 8, 32+4, 32+4,
        sizeof(struct chacha20_ctx),
        chacha20_crypt,
        chacha20_crypt,
        chacha20_setkey,
        chacha20_reinit
};

const struct enc_xform enc_xform_null = {
        CRYPTO_NULL, "NULL",
        4, 0, 0, 256, 0,
        null_encrypt,
        null_decrypt,
        null_setkey,
        NULL
};

/* Authentication instances */
const struct auth_hash auth_hash_hmac_md5_96 = {
        CRYPTO_MD5_HMAC, "HMAC-MD5",
        16, 16, 12, sizeof(MD5_CTX), HMAC_MD5_BLOCK_LEN,
        (void (*) (void *)) MD5Init, NULL, NULL,
        MD5Update_int,
        (void (*) (u_int8_t *, void *)) MD5Final
};

const struct auth_hash auth_hash_hmac_sha1_96 = {
        CRYPTO_SHA1_HMAC, "HMAC-SHA1",
        20, 20, 12, sizeof(SHA1_CTX), HMAC_SHA1_BLOCK_LEN,
        (void (*) (void *)) SHA1Init, NULL, NULL,
        SHA1Update_int,
        (void (*) (u_int8_t *, void *)) SHA1Final
};

const struct auth_hash auth_hash_hmac_ripemd_160_96 = {
        CRYPTO_RIPEMD160_HMAC, "HMAC-RIPEMD-160",
        20, 20, 12, sizeof(RMD160_CTX), HMAC_RIPEMD160_BLOCK_LEN,
        (void (*)(void *)) RMD160Init, NULL, NULL,
        RMD160Update_int,
        (void (*)(u_int8_t *, void *)) RMD160Final
};

const struct auth_hash auth_hash_hmac_sha2_256_128 = {
        CRYPTO_SHA2_256_HMAC, "HMAC-SHA2-256",
        32, 32, 16, sizeof(SHA2_CTX), HMAC_SHA2_256_BLOCK_LEN,
        (void (*)(void *)) SHA256Init, NULL, NULL,
        SHA256Update_int,
        (void (*)(u_int8_t *, void *)) SHA256Final
};

const struct auth_hash auth_hash_hmac_sha2_384_192 = {
        CRYPTO_SHA2_384_HMAC, "HMAC-SHA2-384",
        48, 48, 24, sizeof(SHA2_CTX), HMAC_SHA2_384_BLOCK_LEN,
        (void (*)(void *)) SHA384Init, NULL, NULL,
        SHA384Update_int,
        (void (*)(u_int8_t *, void *)) SHA384Final
};

const struct auth_hash auth_hash_hmac_sha2_512_256 = {
        CRYPTO_SHA2_512_HMAC, "HMAC-SHA2-512",
        64, 64, 32, sizeof(SHA2_CTX), HMAC_SHA2_512_BLOCK_LEN,
        (void (*)(void *)) SHA512Init, NULL, NULL,
        SHA512Update_int,
        (void (*)(u_int8_t *, void *)) SHA512Final
};

const struct auth_hash auth_hash_gmac_aes_128 = {
        CRYPTO_AES_128_GMAC, "GMAC-AES-128",
        16+4, GMAC_BLOCK_LEN, GMAC_DIGEST_LEN, sizeof(AES_GMAC_CTX),
        AESCTR_BLOCKSIZE, AES_GMAC_Init, AES_GMAC_Setkey, AES_GMAC_Reinit,
        AES_GMAC_Update, AES_GMAC_Final
};

const struct auth_hash auth_hash_gmac_aes_192 = {
        CRYPTO_AES_192_GMAC, "GMAC-AES-192",
        24+4, GMAC_BLOCK_LEN, GMAC_DIGEST_LEN, sizeof(AES_GMAC_CTX),
        AESCTR_BLOCKSIZE, AES_GMAC_Init, AES_GMAC_Setkey, AES_GMAC_Reinit,
        AES_GMAC_Update, AES_GMAC_Final
};

const struct auth_hash auth_hash_gmac_aes_256 = {
        CRYPTO_AES_256_GMAC, "GMAC-AES-256",
        32+4, GMAC_BLOCK_LEN, GMAC_DIGEST_LEN, sizeof(AES_GMAC_CTX),
        AESCTR_BLOCKSIZE, AES_GMAC_Init, AES_GMAC_Setkey, AES_GMAC_Reinit,
        AES_GMAC_Update, AES_GMAC_Final
};

const struct auth_hash auth_hash_chacha20_poly1305 = {
        CRYPTO_CHACHA20_POLY1305_MAC, "CHACHA20-POLY1305",
        CHACHA20_KEYSIZE+CHACHA20_SALT, POLY1305_BLOCK_LEN, POLY1305_TAGLEN,
        sizeof(CHACHA20_POLY1305_CTX), CHACHA20_BLOCK_LEN,
        Chacha20_Poly1305_Init, Chacha20_Poly1305_Setkey,
        Chacha20_Poly1305_Reinit, Chacha20_Poly1305_Update,
        Chacha20_Poly1305_Final
};

/* Compression instance */
const struct comp_algo comp_algo_deflate = {
        CRYPTO_DEFLATE_COMP, "Deflate",
        90, deflate_compress,
        deflate_decompress
};

/*
 * Encryption wrapper routines.
 */
void
des3_encrypt(caddr_t key, u_int8_t *blk)
{
        des_ecb3_encrypt(blk, blk, key, key + 128, key + 256, 1);
}

void
des3_decrypt(caddr_t key, u_int8_t *blk)
{
        des_ecb3_encrypt(blk, blk, key + 256, key + 128, key, 0);
}

int
des3_setkey(void *sched, u_int8_t *key, int len)
{
        if (des_set_key(key, sched) < 0 || des_set_key(key + 8, sched + 128)
            < 0 || des_set_key(key + 16, sched + 256) < 0)
                return -1;

        return 0;
}

void
blf_encrypt(caddr_t key, u_int8_t *blk)
{
        blf_ecb_encrypt((blf_ctx *) key, blk, 8);
}

void
blf_decrypt(caddr_t key, u_int8_t *blk)
{
        blf_ecb_decrypt((blf_ctx *) key, blk, 8);
}

int
blf_setkey(void *sched, u_int8_t *key, int len)
{
        blf_key((blf_ctx *)sched, key, len);

        return 0;
}

int
null_setkey(void *sched, u_int8_t *key, int len)
{
        return 0;
}

void
null_encrypt(caddr_t key, u_int8_t *blk)
{
}

void
null_decrypt(caddr_t key, u_int8_t *blk)
{
}

void
cast5_encrypt(caddr_t key, u_int8_t *blk)
{
        cast_encrypt((cast_key *) key, blk, blk);
}

void
cast5_decrypt(caddr_t key, u_int8_t *blk)
{
        cast_decrypt((cast_key *) key, blk, blk);
}

int
cast5_setkey(void *sched, u_int8_t *key, int len)
{
        cast_setkey((cast_key *)sched, key, len);

        return 0;
}

void
aes_encrypt(caddr_t key, u_int8_t *blk)
{
        AES_Encrypt((AES_CTX *)key, blk, blk);
}

void
aes_decrypt(caddr_t key, u_int8_t *blk)
{
        AES_Decrypt((AES_CTX *)key, blk, blk);
}

int
aes_setkey(void *sched, u_int8_t *key, int len)
{
        return AES_Setkey((AES_CTX *)sched, key, len);
}

void
aes_ctr_reinit(caddr_t key, u_int8_t *iv)
{
        struct aes_ctr_ctx *ctx;

        ctx = (struct aes_ctr_ctx *)key;
        bcopy(iv, ctx->ac_block + AESCTR_NONCESIZE, AESCTR_IVSIZE);

        /* reset counter */
        bzero(ctx->ac_block + AESCTR_NONCESIZE + AESCTR_IVSIZE, 4);
}

void
aes_gcm_reinit(caddr_t key, u_int8_t *iv)
{
        struct aes_ctr_ctx *ctx;

        ctx = (struct aes_ctr_ctx *)key;
        bcopy(iv, ctx->ac_block + AESCTR_NONCESIZE, AESCTR_IVSIZE);

        /* reset counter */
        bzero(ctx->ac_block + AESCTR_NONCESIZE + AESCTR_IVSIZE, 4);
        ctx->ac_block[AESCTR_BLOCKSIZE - 1] = 1; /* GCM starts with 1 */
}

void
aes_ctr_crypt(caddr_t key, u_int8_t *data)
{
        struct aes_ctr_ctx *ctx;
        u_int8_t keystream[AESCTR_BLOCKSIZE];
        int i;

        ctx = (struct aes_ctr_ctx *)key;
        /* increment counter */
        for (i = AESCTR_BLOCKSIZE - 1;
             i >= AESCTR_NONCESIZE + AESCTR_IVSIZE; i--)
                if (++ctx->ac_block[i])   /* continue on overflow */
                        break;
        AES_Encrypt(&ctx->ac_key, ctx->ac_block, keystream);
        for (i = 0; i < AESCTR_BLOCKSIZE; i++)
                data[i] ^= keystream[i];
        explicit_bzero(keystream, sizeof(keystream));
}

int
aes_ctr_setkey(void *sched, u_int8_t *key, int len)
{
        struct aes_ctr_ctx *ctx;

        if (len < AESCTR_NONCESIZE)
                return -1;

        ctx = (struct aes_ctr_ctx *)sched;
        if (AES_Setkey(&ctx->ac_key, key, len - AESCTR_NONCESIZE) != 0)
                return -1;
        bcopy(key + len - AESCTR_NONCESIZE, ctx->ac_block, AESCTR_NONCESIZE);
        return 0;
}

void
aes_xts_reinit(caddr_t key, u_int8_t *iv)
{
        struct aes_xts_ctx *ctx = (struct aes_xts_ctx *)key;
        u_int64_t blocknum;
        u_int i;

        /*
         * Prepare tweak as E_k2(IV). IV is specified as LE representation
         * of a 64-bit block number which we allow to be passed in directly.
         */
        memcpy(&blocknum, iv, AES_XTS_IVSIZE);
        for (i = 0; i < AES_XTS_IVSIZE; i++) {
                ctx->tweak[i] = blocknum & 0xff;
                blocknum >>= 8;
        }
        /* Last 64 bits of IV are always zero */
        bzero(ctx->tweak + AES_XTS_IVSIZE, AES_XTS_IVSIZE);

        rijndael_encrypt(&ctx->key2, ctx->tweak, ctx->tweak);
}

void
aes_xts_crypt(struct aes_xts_ctx *ctx, u_int8_t *data, u_int do_encrypt)
{
        u_int8_t block[AES_XTS_BLOCKSIZE];
        u_int i, carry_in, carry_out;

        for (i = 0; i < AES_XTS_BLOCKSIZE; i++)
                block[i] = data[i] ^ ctx->tweak[i];

        if (do_encrypt)
                rijndael_encrypt(&ctx->key1, block, data);
        else
                rijndael_decrypt(&ctx->key1, block, data);

        for (i = 0; i < AES_XTS_BLOCKSIZE; i++)
                data[i] ^= ctx->tweak[i];

        /* Exponentiate tweak */
        carry_in = 0;
        for (i = 0; i < AES_XTS_BLOCKSIZE; i++) {
                carry_out = ctx->tweak[i] & 0x80;
                ctx->tweak[i] = (ctx->tweak[i] << 1) | carry_in;
                carry_in = carry_out >> 7;
        }
        ctx->tweak[0] ^= (AES_XTS_ALPHA & -carry_in);
        explicit_bzero(block, sizeof(block));
}

void
aes_xts_encrypt(caddr_t key, u_int8_t *data)
{
        aes_xts_crypt((struct aes_xts_ctx *)key, data, 1);
}

void
aes_xts_decrypt(caddr_t key, u_int8_t *data)
{
        aes_xts_crypt((struct aes_xts_ctx *)key, data, 0);
}

int
aes_xts_setkey(void *sched, u_int8_t *key, int len)
{
        struct aes_xts_ctx *ctx;

        if (len != 32 && len != 64)
                return -1;

        ctx = (struct aes_xts_ctx *)sched;

        rijndael_set_key(&ctx->key1, key, len * 4);
        rijndael_set_key(&ctx->key2, key + (len / 2), len * 4);

        return 0;
}

/*
 * And now for auth.
 */

int
RMD160Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        RMD160Update(ctx, buf, len);
        return 0;
}

int
MD5Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        MD5Update(ctx, buf, len);
        return 0;
}

int
SHA1Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        SHA1Update(ctx, buf, len);
        return 0;
}

int
SHA256Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        SHA256Update(ctx, buf, len);
        return 0;
}

int
SHA384Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        SHA384Update(ctx, buf, len);
        return 0;
}

int
SHA512Update_int(void *ctx, const u_int8_t *buf, u_int16_t len)
{
        SHA512Update(ctx, buf, len);
        return 0;
}


u_int32_t deflate_global(u_int8_t *, u_int32_t, int, u_int8_t **);

struct deflate_buf {
        u_int8_t *out;
        u_int32_t size;
        int flag;
};

/*
 * And compression
 */

u_int32_t
deflate_compress(u_int8_t *data, u_int32_t size, u_int8_t **out)
{
        return deflate_global(data, size, 0, out);
}

u_int32_t
deflate_decompress(u_int8_t *data, u_int32_t size, u_int8_t **out)
{
        return deflate_global(data, size, 1, out);
}