/* * Glue Code for 3-way parallel assembler optimized version of Twofish * * Copyright (c) 2011 Jussi Kivilinna * * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by: * Copyright (c) 2006 Herbert Xu * CTR part based on code (crypto/ctr.c) by: * (C) Copyright IBM Corp. 2007 - Joy Latten * * This program 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 2 of the License, or * (at your option) any later version. * * This program 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 this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA * */ #include #include #include #include #include #include #include #include #include #if defined(CONFIG_CRYPTO_LRW) || defined(CONFIG_CRYPTO_LRW_MODULE) #define HAS_LRW #endif #if defined(CONFIG_CRYPTO_XTS) || defined(CONFIG_CRYPTO_XTS_MODULE) #define HAS_XTS #endif /* regular block cipher functions from twofish_x86_64 module */ asmlinkage void twofish_enc_blk(struct twofish_ctx *ctx, u8 *dst, const u8 *src); asmlinkage void twofish_dec_blk(struct twofish_ctx *ctx, u8 *dst, const u8 *src); /* 3-way parallel cipher functions */ asmlinkage void __twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst, const u8 *src, bool xor); asmlinkage void twofish_dec_blk_3way(struct twofish_ctx *ctx, u8 *dst, const u8 *src); static inline void twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst, const u8 *src) { __twofish_enc_blk_3way(ctx, dst, src, false); } static inline void twofish_enc_blk_xor_3way(struct twofish_ctx *ctx, u8 *dst, const u8 *src) { __twofish_enc_blk_3way(ctx, dst, src, true); } static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, void (*fn)(struct twofish_ctx *, u8 *, const u8 *), void (*fn_3way)(struct twofish_ctx *, u8 *, const u8 *)) { struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); unsigned int bsize = TF_BLOCK_SIZE; unsigned int nbytes; int err; err = blkcipher_walk_virt(desc, walk); while ((nbytes = walk->nbytes)) { u8 *wsrc = walk->src.virt.addr; u8 *wdst = walk->dst.virt.addr; /* Process three block batch */ if (nbytes >= bsize * 3) { do { fn_3way(ctx, wdst, wsrc); wsrc += bsize * 3; wdst += bsize * 3; nbytes -= bsize * 3; } while (nbytes >= bsize * 3); if (nbytes < bsize) goto done; } /* Handle leftovers */ do { fn(ctx, wdst, wsrc); wsrc += bsize; wdst += bsize; nbytes -= bsize; } while (nbytes >= bsize); done: err = blkcipher_walk_done(desc, walk, nbytes); } return err; } static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct blkcipher_walk walk; blkcipher_walk_init(&walk, dst, src, nbytes); return ecb_crypt(desc, &walk, twofish_enc_blk, twofish_enc_blk_3way); } static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct blkcipher_walk walk; blkcipher_walk_init(&walk, dst, src, nbytes); return ecb_crypt(desc, &walk, twofish_dec_blk, twofish_dec_blk_3way); } static struct crypto_alg blk_ecb_alg = { .cra_name = "ecb(twofish)", .cra_driver_name = "ecb-twofish-3way", .cra_priority = 300, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = TF_BLOCK_SIZE, .cra_ctxsize = sizeof(struct twofish_ctx), .cra_alignmask = 0, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(blk_ecb_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = TF_MIN_KEY_SIZE, .max_keysize = TF_MAX_KEY_SIZE, .setkey = twofish_setkey, .encrypt = ecb_encrypt, .decrypt = ecb_decrypt, }, }, }; static unsigned int __cbc_encrypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); unsigned int bsize = TF_BLOCK_SIZE; unsigned int nbytes = walk->nbytes; u128 *src = (u128 *)walk->src.virt.addr; u128 *dst = (u128 *)walk->dst.virt.addr; u128 *iv = (u128 *)walk->iv; do { u128_xor(dst, src, iv); twofish_enc_blk(ctx, (u8 *)dst, (u8 *)dst); iv = dst; src += 1; dst += 1; nbytes -= bsize; } while (nbytes >= bsize); u128_xor((u128 *)walk->iv, (u128 *)walk->iv, iv); return nbytes; } static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct blkcipher_walk walk; int err; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { nbytes = __cbc_encrypt(desc, &walk); err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static unsigned int __cbc_decrypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); unsigned int bsize = TF_BLOCK_SIZE; unsigned int nbytes = walk->nbytes; u128 *src = (u128 *)walk->src.virt.addr; u128 *dst = (u128 *)walk->dst.virt.addr; u128 ivs[3 - 1]; u128 last_iv; /* Start of the last block. */ src += nbytes / bsize - 1; dst += nbytes / bsize - 1; last_iv = *src; /* Process three block batch */ if (nbytes >= bsize * 3) { do { nbytes -= bsize * (3 - 1); src -= 3 - 1; dst -= 3 - 1; ivs[0] = src[0]; ivs[1] = src[1]; twofish_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src); u128_xor(dst + 1, dst + 1, ivs + 0); u128_xor(dst + 2, dst + 2, ivs + 1); nbytes -= bsize; if (nbytes < bsize) goto done; u128_xor(dst, dst, src - 1); src -= 1; dst -= 1; } while (nbytes >= bsize * 3); if (nbytes < bsize) goto done; } /* Handle leftovers */ for (;;) { twofish_dec_blk(ctx, (u8 *)dst, (u8 *)src); nbytes -= bsize; if (nbytes < bsize) break; u128_xor(dst, dst, src - 1); src -= 1; dst -= 1; } done: u128_xor(dst, dst, (u128 *)walk->iv); *(u128 *)walk->iv = last_iv; return nbytes; } static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct blkcipher_walk walk; int err; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { nbytes = __cbc_decrypt(desc, &walk); err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static struct crypto_alg blk_cbc_alg = { .cra_name = "cbc(twofish)", .cra_driver_name = "cbc-twofish-3way", .cra_priority = 300, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = TF_BLOCK_SIZE, .cra_ctxsize = sizeof(struct twofish_ctx), .cra_alignmask = 0, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(blk_cbc_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = TF_MIN_KEY_SIZE, .max_keysize = TF_MAX_KEY_SIZE, .ivsize = TF_BLOCK_SIZE, .setkey = twofish_setkey, .encrypt = cbc_encrypt, .decrypt = cbc_decrypt, }, }, }; static inline void u128_to_be128(be128 *dst, const u128 *src) { dst->a = cpu_to_be64(src->a); dst->b = cpu_to_be64(src->b); } static inline void be128_to_u128(u128 *dst, const be128 *src) { dst->a = be64_to_cpu(src->a); dst->b = be64_to_cpu(src->b); } static inline void u128_inc(u128 *i) { i->b++; if (!i->b) i->a++; } static void ctr_crypt_final(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); u8 *ctrblk = walk->iv; u8 keystream[TF_BLOCK_SIZE]; u8 *src = walk->src.virt.addr; u8 *dst = walk->dst.virt.addr; unsigned int nbytes = walk->nbytes; twofish_enc_blk(ctx, keystream, ctrblk); crypto_xor(keystream, src, nbytes); memcpy(dst, keystream, nbytes); crypto_inc(ctrblk, TF_BLOCK_SIZE); } static unsigned int __ctr_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); unsigned int bsize = TF_BLOCK_SIZE; unsigned int nbytes = walk->nbytes; u128 *src = (u128 *)walk->src.virt.addr; u128 *dst = (u128 *)walk->dst.virt.addr; u128 ctrblk; be128 ctrblocks[3]; be128_to_u128(&ctrblk, (be128 *)walk->iv); /* Process three block batch */ if (nbytes >= bsize * 3) { do { if (dst != src) { dst[0] = src[0]; dst[1] = src[1]; dst[2] = src[2]; } /* create ctrblks for parallel encrypt */ u128_to_be128(&ctrblocks[0], &ctrblk); u128_inc(&ctrblk); u128_to_be128(&ctrblocks[1], &ctrblk); u128_inc(&ctrblk); u128_to_be128(&ctrblocks[2], &ctrblk); u128_inc(&ctrblk); twofish_enc_blk_xor_3way(ctx, (u8 *)dst, (u8 *)ctrblocks); src += 3; dst += 3; nbytes -= bsize * 3; } while (nbytes >= bsize * 3); if (nbytes < bsize) goto done; } /* Handle leftovers */ do { if (dst != src) *dst = *src; u128_to_be128(&ctrblocks[0], &ctrblk); u128_inc(&ctrblk); twofish_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks); u128_xor(dst, dst, (u128 *)ctrblocks); src += 1; dst += 1; nbytes -= bsize; } while (nbytes >= bsize); done: u128_to_be128((be128 *)walk->iv, &ctrblk); return nbytes; } static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct blkcipher_walk walk; int err; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt_block(desc, &walk, TF_BLOCK_SIZE); while ((nbytes = walk.nbytes) >= TF_BLOCK_SIZE) { nbytes = __ctr_crypt(desc, &walk); err = blkcipher_walk_done(desc, &walk, nbytes); } if (walk.nbytes) { ctr_crypt_final(desc, &walk); err = blkcipher_walk_done(desc, &walk, 0); } return err; } static struct crypto_alg blk_ctr_alg = { .cra_name = "ctr(twofish)", .cra_driver_name = "ctr-twofish-3way", .cra_priority = 300, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = 1, .cra_ctxsize = sizeof(struct twofish_ctx), .cra_alignmask = 0, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(blk_ctr_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = TF_MIN_KEY_SIZE, .max_keysize = TF_MAX_KEY_SIZE, .ivsize = TF_BLOCK_SIZE, .setkey = twofish_setkey, .encrypt = ctr_crypt, .decrypt = ctr_crypt, }, }, }; #if defined(HAS_LRW) || defined(HAS_XTS) static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = TF_BLOCK_SIZE; struct twofish_ctx *ctx = priv; int i; if (nbytes == 3 * bsize) { twofish_enc_blk_3way(ctx, srcdst, srcdst); return; } for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) twofish_enc_blk(ctx, srcdst, srcdst); } static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = TF_BLOCK_SIZE; struct twofish_ctx *ctx = priv; int i; if (nbytes == 3 * bsize) { twofish_dec_blk_3way(ctx, srcdst, srcdst); return; } for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) twofish_dec_blk(ctx, srcdst, srcdst); } #endif #ifdef HAS_LRW struct twofish_lrw_ctx { struct lrw_table_ctx lrw_table; struct twofish_ctx twofish_ctx; }; static int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) { struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm); int err; err = __twofish_setkey(&ctx->twofish_ctx, key, keylen - TF_BLOCK_SIZE, &tfm->crt_flags); if (err) return err; return lrw_init_table(&ctx->lrw_table, key + keylen - TF_BLOCK_SIZE); } static int lrw_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); be128 buf[3]; struct lrw_crypt_req req = { .tbuf = buf, .tbuflen = sizeof(buf), .table_ctx = &ctx->lrw_table, .crypt_ctx = &ctx->twofish_ctx, .crypt_fn = encrypt_callback, }; return lrw_crypt(desc, dst, src, nbytes, &req); } static int lrw_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); be128 buf[3]; struct lrw_crypt_req req = { .tbuf = buf, .tbuflen = sizeof(buf), .table_ctx = &ctx->lrw_table, .crypt_ctx = &ctx->twofish_ctx, .crypt_fn = decrypt_callback, }; return lrw_crypt(desc, dst, src, nbytes, &req); } static void lrw_exit_tfm(struct crypto_tfm *tfm) { struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm); lrw_free_table(&ctx->lrw_table); } static struct crypto_alg blk_lrw_alg = { .cra_name = "lrw(twofish)", .cra_driver_name = "lrw-twofish-3way", .cra_priority = 300, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = TF_BLOCK_SIZE, .cra_ctxsize = sizeof(struct twofish_lrw_ctx), .cra_alignmask = 0, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(blk_lrw_alg.cra_list), .cra_exit = lrw_exit_tfm, .cra_u = { .blkcipher = { .min_keysize = TF_MIN_KEY_SIZE + TF_BLOCK_SIZE, .max_keysize = TF_MAX_KEY_SIZE + TF_BLOCK_SIZE, .ivsize = TF_BLOCK_SIZE, .setkey = lrw_twofish_setkey, .encrypt = lrw_encrypt, .decrypt = lrw_decrypt, }, }, }; #endif #ifdef HAS_XTS struct twofish_xts_ctx { struct twofish_ctx tweak_ctx; struct twofish_ctx crypt_ctx; }; static int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) { struct twofish_xts_ctx *ctx = crypto_tfm_ctx(tfm); u32 *flags = &tfm->crt_flags; int err; /* key consists of keys of equal size concatenated, therefore * the length must be even */ if (keylen % 2) { *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; return -EINVAL; } /* first half of xts-key is for crypt */ err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2, flags); if (err) return err; /* second half of xts-key is for tweak */ return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2, flags); } static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); be128 buf[3]; struct xts_crypt_req req = { .tbuf = buf, .tbuflen = sizeof(buf), .tweak_ctx = &ctx->tweak_ctx, .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk), .crypt_ctx = &ctx->crypt_ctx, .crypt_fn = encrypt_callback, }; return xts_crypt(desc, dst, src, nbytes, &req); } static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); be128 buf[3]; struct xts_crypt_req req = { .tbuf = buf, .tbuflen = sizeof(buf), .tweak_ctx = &ctx->tweak_ctx, .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk), .crypt_ctx = &ctx->crypt_ctx, .crypt_fn = decrypt_callback, }; return xts_crypt(desc, dst, src, nbytes, &req); } static struct crypto_alg blk_xts_alg = { .cra_name = "xts(twofish)", .cra_driver_name = "xts-twofish-3way", .cra_priority = 300, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = TF_BLOCK_SIZE, .cra_ctxsize = sizeof(struct twofish_xts_ctx), .cra_alignmask = 0, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(blk_xts_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = TF_MIN_KEY_SIZE * 2, .max_keysize = TF_MAX_KEY_SIZE * 2, .ivsize = TF_BLOCK_SIZE, .setkey = xts_twofish_setkey, .encrypt = xts_encrypt, .decrypt = xts_decrypt, }, }, }; #endif int __init init(void) { int err; err = crypto_register_alg(&blk_ecb_alg); if (err) goto ecb_err; err = crypto_register_alg(&blk_cbc_alg); if (err) goto cbc_err; err = crypto_register_alg(&blk_ctr_alg); if (err) goto ctr_err; #ifdef HAS_LRW err = crypto_register_alg(&blk_lrw_alg); if (err) goto blk_lrw_err; #endif #ifdef HAS_XTS err = crypto_register_alg(&blk_xts_alg); if (err) goto blk_xts_err; #endif return 0; #ifdef HAS_XTS crypto_unregister_alg(&blk_xts_alg); blk_xts_err: #endif #ifdef HAS_LRW crypto_unregister_alg(&blk_lrw_alg); blk_lrw_err: #endif crypto_unregister_alg(&blk_ctr_alg); ctr_err: crypto_unregister_alg(&blk_cbc_alg); cbc_err: crypto_unregister_alg(&blk_ecb_alg); ecb_err: return err; } void __exit fini(void) { #ifdef HAS_XTS crypto_unregister_alg(&blk_xts_alg); #endif #ifdef HAS_LRW crypto_unregister_alg(&blk_lrw_alg); #endif crypto_unregister_alg(&blk_ctr_alg); crypto_unregister_alg(&blk_cbc_alg); crypto_unregister_alg(&blk_ecb_alg); } module_init(init); module_exit(fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Twofish Cipher Algorithm, 3-way parallel asm optimized"); MODULE_ALIAS("twofish"); MODULE_ALIAS("twofish-asm");