crypto: des_3des - add x86-64 assembly implementation

Patch adds x86_64 assembly implementation of Triple DES EDE cipher algorithm.
Two assembly implementations are provided. First is regular 'one-block at
time' encrypt/decrypt function. Second is 'three-blocks at time' function that
gains performance increase on out-of-order CPUs.

tcrypt test results:

Intel Core i5-4570:

des3_ede-asm vs des3_ede-generic:
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec
16B     1.21x   1.22x   1.27x   1.36x   1.25x   1.25x
64B     1.98x   1.96x   1.23x   2.04x   2.01x   2.00x
256B    2.34x   2.37x   1.21x   2.40x   2.38x   2.39x
1024B   2.50x   2.47x   1.22x   2.51x   2.52x   2.51x
8192B   2.51x   2.53x   1.21x   2.56x   2.54x   2.55x

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 509 insertions, 0 deletions

diff --git a/arch/x86/crypto/des3_ede_glue.c b/arch/x86/crypto/des3_ede_glue.c
new file mode 100644
index 000000000000..ebc421543e44
--- /dev/null
+++ b/arch/x86/crypto/des3_ede_glue.c
@@ -0,0 +1,509 @@
+/*
+ * Glue Code for assembler optimized version of 3DES
+ *
+ * Copyright © 2014 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
+ *
+ * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
+ *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
+ * CTR part based on code (crypto/ctr.c) by:
+ *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
+ *
+ * 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.
+ *
+ */
+
+#include <asm/processor.h>
+#include <crypto/des.h>
+#include <linux/crypto.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <crypto/algapi.h>
+
+struct des3_ede_x86_ctx {
+        u32 enc_expkey[DES3_EDE_EXPKEY_WORDS];
+        u32 dec_expkey[DES3_EDE_EXPKEY_WORDS];
+};
+
+/* regular block cipher functions */
+asmlinkage void des3_ede_x86_64_crypt_blk(const u32 *expkey, u8 *dst,
+                                          const u8 *src);
+
+/* 3-way parallel cipher functions */
+asmlinkage void des3_ede_x86_64_crypt_blk_3way(const u32 *expkey, u8 *dst,
+                                               const u8 *src);
+
+static inline void des3_ede_enc_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
+                                    const u8 *src)
+{
+        u32 *enc_ctx = ctx->enc_expkey;
+
+        des3_ede_x86_64_crypt_blk(enc_ctx, dst, src);
+}
+
+static inline void des3_ede_dec_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
+                                    const u8 *src)
+{
+        u32 *dec_ctx = ctx->dec_expkey;
+
+        des3_ede_x86_64_crypt_blk(dec_ctx, dst, src);
+}
+
+static inline void des3_ede_enc_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
+                                         const u8 *src)
+{
+        u32 *enc_ctx = ctx->enc_expkey;
+
+        des3_ede_x86_64_crypt_blk_3way(enc_ctx, dst, src);
+}
+
+static inline void des3_ede_dec_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
+                                         const u8 *src)
+{
+        u32 *dec_ctx = ctx->dec_expkey;
+
+        des3_ede_x86_64_crypt_blk_3way(dec_ctx, dst, src);
+}
+
+static void des3_ede_x86_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+        des3_ede_enc_blk(crypto_tfm_ctx(tfm), dst, src);
+}
+
+static void des3_ede_x86_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+        des3_ede_dec_blk(crypto_tfm_ctx(tfm), dst, src);
+}
+
+static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
+                     const u32 *expkey)
+{
+        unsigned int bsize = DES3_EDE_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 four block batch */
+                if (nbytes >= bsize * 3) {
+                        do {
+                                des3_ede_x86_64_crypt_blk_3way(expkey, wdst,
+                                                               wsrc);
+
+                                wsrc += bsize * 3;
+                                wdst += bsize * 3;
+                                nbytes -= bsize * 3;
+                        } while (nbytes >= bsize * 3);
+
+                        if (nbytes < bsize)
+                                goto done;
+                }
+
+                /* Handle leftovers */
+                do {
+                        des3_ede_x86_64_crypt_blk(expkey, 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 des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+        struct blkcipher_walk walk;
+
+        blkcipher_walk_init(&walk, dst, src, nbytes);
+        return ecb_crypt(desc, &walk, ctx->enc_expkey);
+}
+
+static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+                       struct scatterlist *src, unsigned int nbytes)
+{
+        struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+        struct blkcipher_walk walk;
+
+        blkcipher_walk_init(&walk, dst, src, nbytes);
+        return ecb_crypt(desc, &walk, ctx->dec_expkey);
+}
+
+static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
+                                  struct blkcipher_walk *walk)
+{
+        struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+        unsigned int bsize = DES3_EDE_BLOCK_SIZE;
+        unsigned int nbytes = walk->nbytes;
+        u64 *src = (u64 *)walk->src.virt.addr;
+        u64 *dst = (u64 *)walk->dst.virt.addr;
+        u64 *iv = (u64 *)walk->iv;
+
+        do {
+                *dst = *src ^ *iv;
+                des3_ede_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
+                iv = dst;
+
+                src += 1;
+                dst += 1;
+                nbytes -= bsize;
+        } while (nbytes >= bsize);
+
+        *(u64 *)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 des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+        unsigned int bsize = DES3_EDE_BLOCK_SIZE;
+        unsigned int nbytes = walk->nbytes;
+        u64 *src = (u64 *)walk->src.virt.addr;
+        u64 *dst = (u64 *)walk->dst.virt.addr;
+        u64 ivs[3 - 1];
+        u64 last_iv;
+
+        /* Start of the last block. */
+        src += nbytes / bsize - 1;
+        dst += nbytes / bsize - 1;
+
+        last_iv = *src;
+
+        /* Process four block batch */
+        if (nbytes >= bsize * 3) {
+                do {
+                        nbytes -= bsize * 3 - bsize;
+                        src -= 3 - 1;
+                        dst -= 3 - 1;
+
+                        ivs[0] = src[0];
+                        ivs[1] = src[1];
+
+                        des3_ede_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
+
+                        dst[1] ^= ivs[0];
+                        dst[2] ^= ivs[1];
+
+                        nbytes -= bsize;
+                        if (nbytes < bsize)
+                                goto done;
+
+                        *dst ^= *(src - 1);
+                        src -= 1;
+                        dst -= 1;
+                } while (nbytes >= bsize * 3);
+        }
+
+        /* Handle leftovers */
+        for (;;) {
+                des3_ede_dec_blk(ctx, (u8 *)dst, (u8 *)src);
+
+                nbytes -= bsize;
+                if (nbytes < bsize)
+                        break;
+
+                *dst ^= *(src - 1);
+                src -= 1;
+                dst -= 1;
+        }
+
+done:
+        *dst ^= *(u64 *)walk->iv;
+        *(u64 *)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 void ctr_crypt_final(struct des3_ede_x86_ctx *ctx,
+                            struct blkcipher_walk *walk)
+{
+        u8 *ctrblk = walk->iv;
+        u8 keystream[DES3_EDE_BLOCK_SIZE];
+        u8 *src = walk->src.virt.addr;
+        u8 *dst = walk->dst.virt.addr;
+        unsigned int nbytes = walk->nbytes;
+
+        des3_ede_enc_blk(ctx, keystream, ctrblk);
+        crypto_xor(keystream, src, nbytes);
+        memcpy(dst, keystream, nbytes);
+
+        crypto_inc(ctrblk, DES3_EDE_BLOCK_SIZE);
+}
+
+static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
+                                struct blkcipher_walk *walk)
+{
+        struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+        unsigned int bsize = DES3_EDE_BLOCK_SIZE;
+        unsigned int nbytes = walk->nbytes;
+        u64 *src = (u64 *)walk->src.virt.addr;
+        u64 *dst = (u64 *)walk->dst.virt.addr;
+        u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
+        __be64 ctrblocks[3];
+
+        /* Process four block batch */
+        if (nbytes >= bsize * 3) {
+                do {
+                        /* create ctrblks for parallel encrypt */
+                        ctrblocks[0] = cpu_to_be64(ctrblk++);
+                        ctrblocks[1] = cpu_to_be64(ctrblk++);
+                        ctrblocks[2] = cpu_to_be64(ctrblk++);
+
+                        des3_ede_enc_blk_3way(ctx, (u8 *)ctrblocks,
+                                              (u8 *)ctrblocks);
+
+                        dst[0] = src[0] ^ ctrblocks[0];
+                        dst[1] = src[1] ^ ctrblocks[1];
+                        dst[2] = src[2] ^ ctrblocks[2];
+
+                        src += 3;
+                        dst += 3;
+                } while ((nbytes -= bsize * 3) >= bsize * 3);
+
+                if (nbytes < bsize)
+                        goto done;
+        }
+
+        /* Handle leftovers */
+        do {
+                ctrblocks[0] = cpu_to_be64(ctrblk++);
+
+                des3_ede_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
+
+                dst[0] = src[0] ^ ctrblocks[0];
+
+                src += 1;
+                dst += 1;
+        } while ((nbytes -= bsize) >= bsize);
+
+done:
+        *(__be64 *)walk->iv = cpu_to_be64(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, DES3_EDE_BLOCK_SIZE);
+
+        while ((nbytes = walk.nbytes) >= DES3_EDE_BLOCK_SIZE) {
+                nbytes = __ctr_crypt(desc, &walk);
+                err = blkcipher_walk_done(desc, &walk, nbytes);
+        }
+
+        if (walk.nbytes) {
+                ctr_crypt_final(crypto_blkcipher_ctx(desc->tfm), &walk);
+                err = blkcipher_walk_done(desc, &walk, 0);
+        }
+
+        return err;
+}
+
+static int des3_ede_x86_setkey(struct crypto_tfm *tfm, const u8 *key,
+                               unsigned int keylen)
+{
+        struct des3_ede_x86_ctx *ctx = crypto_tfm_ctx(tfm);
+        u32 i, j, tmp;
+        int err;
+
+        /* Generate encryption context using generic implementation. */
+        err = __des3_ede_setkey(ctx->enc_expkey, &tfm->crt_flags, key, keylen);
+        if (err < 0)
+                return err;
+
+        /* Fix encryption context for this implementation and form decryption
+         * context. */
+        j = DES3_EDE_EXPKEY_WORDS - 2;
+        for (i = 0; i < DES3_EDE_EXPKEY_WORDS; i += 2, j -= 2) {
+                tmp = ror32(ctx->enc_expkey[i + 1], 4);
+                ctx->enc_expkey[i + 1] = tmp;
+
+                ctx->dec_expkey[j + 0] = ctx->enc_expkey[i + 0];
+                ctx->dec_expkey[j + 1] = tmp;
+        }
+
+        return 0;
+}
+
+static struct crypto_alg des3_ede_algs[4] = { {
+        .cra_name               = "des3_ede",
+        .cra_driver_name        = "des3_ede-asm",
+        .cra_priority           = 200,
+        .cra_flags              = CRYPTO_ALG_TYPE_CIPHER,
+        .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
+        .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
+        .cra_alignmask          = 0,
+        .cra_module             = THIS_MODULE,
+        .cra_u = {
+                .cipher = {
+                        .cia_min_keysize        = DES3_EDE_KEY_SIZE,
+                        .cia_max_keysize        = DES3_EDE_KEY_SIZE,
+                        .cia_setkey             = des3_ede_x86_setkey,
+                        .cia_encrypt            = des3_ede_x86_encrypt,
+                        .cia_decrypt            = des3_ede_x86_decrypt,
+                }
+        }
+}, {
+        .cra_name               = "ecb(des3_ede)",
+        .cra_driver_name        = "ecb-des3_ede-asm",
+        .cra_priority           = 300,
+        .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
+        .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
+        .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
+        .cra_alignmask          = 0,
+        .cra_type               = &crypto_blkcipher_type,
+        .cra_module             = THIS_MODULE,
+        .cra_u = {
+                .blkcipher = {
+                        .min_keysize    = DES3_EDE_KEY_SIZE,
+                        .max_keysize    = DES3_EDE_KEY_SIZE,
+                        .setkey         = des3_ede_x86_setkey,
+                        .encrypt        = ecb_encrypt,
+                        .decrypt        = ecb_decrypt,
+                },
+        },
+}, {
+        .cra_name               = "cbc(des3_ede)",
+        .cra_driver_name        = "cbc-des3_ede-asm",
+        .cra_priority           = 300,
+        .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
+        .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
+        .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
+        .cra_alignmask          = 0,
+        .cra_type               = &crypto_blkcipher_type,
+        .cra_module             = THIS_MODULE,
+        .cra_u = {
+                .blkcipher = {
+                        .min_keysize    = DES3_EDE_KEY_SIZE,
+                        .max_keysize    = DES3_EDE_KEY_SIZE,
+                        .ivsize         = DES3_EDE_BLOCK_SIZE,
+                        .setkey         = des3_ede_x86_setkey,
+                        .encrypt        = cbc_encrypt,
+                        .decrypt        = cbc_decrypt,
+                },
+        },
+}, {
+        .cra_name               = "ctr(des3_ede)",
+        .cra_driver_name        = "ctr-des3_ede-asm",
+        .cra_priority           = 300,
+        .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
+        .cra_blocksize          = 1,
+        .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
+        .cra_alignmask          = 0,
+        .cra_type               = &crypto_blkcipher_type,
+        .cra_module             = THIS_MODULE,
+        .cra_u = {
+                .blkcipher = {
+                        .min_keysize    = DES3_EDE_KEY_SIZE,
+                        .max_keysize    = DES3_EDE_KEY_SIZE,
+                        .ivsize         = DES3_EDE_BLOCK_SIZE,
+                        .setkey         = des3_ede_x86_setkey,
+                        .encrypt        = ctr_crypt,
+                        .decrypt        = ctr_crypt,
+                },
+        },
+} };
+
+static bool is_blacklisted_cpu(void)
+{
+        if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+                return false;
+
+        if (boot_cpu_data.x86 == 0x0f) {
+                /*
+                 * On Pentium 4, des3_ede-x86_64 is slower than generic C
+                 * implementation because use of 64bit rotates (which are really
+                 * slow on P4). Therefore blacklist P4s.
+                 */
+                return true;
+        }
+
+        return false;
+}
+
+static int force;
+module_param(force, int, 0);
+MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
+
+static int __init des3_ede_x86_init(void)
+{
+        if (!force && is_blacklisted_cpu()) {
+                pr_info("des3_ede-x86_64: performance on this CPU would be suboptimal: disabling des3_ede-x86_64.\n");
+                return -ENODEV;
+        }
+
+        return crypto_register_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
+}
+
+static void __exit des3_ede_x86_fini(void)
+{
+        crypto_unregister_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
+}
+
+module_init(des3_ede_x86_init);
+module_exit(des3_ede_x86_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Triple DES EDE Cipher Algorithm, asm optimized");
+MODULE_ALIAS("des3_ede");
+MODULE_ALIAS("des3_ede-asm");
+MODULE_ALIAS("des");
+MODULE_ALIAS("des-asm");
+MODULE_AUTHOR("Jussi Kivilinna <jussi.kivilinna@iki.fi>");