crypto: arm64/sm4 - add CE implementation for CCM mode

This patch is a CE-optimized assembly implementation for CCM mode.

Benchmark on T-Head Yitian-710 2.75 GHz, the data comes from the 223 and 225
modes of tcrypt, and compared the performance before and after this patch (the
driver used before this patch is ccm_base(ctr-sm4-ce,cbcmac-sm4-ce)).
The abscissas are blocks of different lengths. The data is tabulated and the
unit is Mb/s:

Before (rfc4309(ccm_base(ctr-sm4-ce,cbcmac-sm4-ce))):

ccm(sm4)     |     16      64     256     512    1024    1420    4096    8192
-------------+---------------------------------------------------------------
  CCM enc    |  35.07  125.40  336.47  468.17  581.97  619.18  712.56  736.01
  CCM dec    |  34.87  124.40  335.08  466.75  581.04  618.81  712.25  735.89
  CCM mb enc |  34.71  123.96  333.92  465.39  579.91  617.49  711.45  734.92
  CCM mb dec |  34.42  122.80  331.02  462.81  578.28  616.42  709.88  734.19

After (rfc4309(ccm-sm4-ce)):

ccm-sm4-ce   |     16      64     256     512    1024    1420    4096    8192
-------------+---------------------------------------------------------------
  CCM enc    |  77.12  249.82  569.94  725.17  839.27  867.71  952.87  969.89
  CCM dec    |  75.90  247.26  566.29  722.12  836.90  865.95  951.74  968.57
  CCM mb enc |  75.98  245.25  562.91  718.99  834.76  864.70  950.17  967.90
  CCM mb dec |  75.06  243.78  560.58  717.13  833.68  862.70  949.35  967.11

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 303 insertions, 0 deletions

diff --git a/arch/arm64/crypto/sm4-ce-ccm-glue.c b/arch/arm64/crypto/sm4-ce-ccm-glue.c
new file mode 100644
index 000000000000..f2cec7b52efc
--- /dev/null
+++ b/arch/arm64/crypto/sm4-ce-ccm-glue.c
@@ -0,0 +1,303 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * SM4-CCM AEAD Algorithm using ARMv8 Crypto Extensions
+ * as specified in rfc8998
+ * https://datatracker.ietf.org/doc/html/rfc8998
+ *
+ * Copyright (C) 2022 Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/kernel.h>
+#include <linux/cpufeature.h>
+#include <asm/neon.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/sm4.h>
+#include "sm4-ce.h"
+
+asmlinkage void sm4_ce_cbcmac_update(const u32 *rkey_enc, u8 *mac,
+				     const u8 *src, unsigned int nblocks);
+asmlinkage void sm4_ce_ccm_enc(const u32 *rkey_enc, u8 *dst, const u8 *src,
+			       u8 *iv, unsigned int nbytes, u8 *mac);
+asmlinkage void sm4_ce_ccm_dec(const u32 *rkey_enc, u8 *dst, const u8 *src,
+			       u8 *iv, unsigned int nbytes, u8 *mac);
+asmlinkage void sm4_ce_ccm_final(const u32 *rkey_enc, u8 *iv, u8 *mac);
+
+
+static int ccm_setkey(struct crypto_aead *tfm, const u8 *key,
+		      unsigned int key_len)
+{
+	struct sm4_ctx *ctx = crypto_aead_ctx(tfm);
+
+	if (key_len != SM4_KEY_SIZE)
+		return -EINVAL;
+
+	kernel_neon_begin();
+	sm4_ce_expand_key(key, ctx->rkey_enc, ctx->rkey_dec,
+			  crypto_sm4_fk, crypto_sm4_ck);
+	kernel_neon_end();
+
+	return 0;
+}
+
+static int ccm_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+	if ((authsize & 1) || authsize < 4)
+		return -EINVAL;
+	return 0;
+}
+
+static int ccm_format_input(u8 info[], struct aead_request *req,
+			    unsigned int msglen)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	unsigned int l = req->iv[0] + 1;
+	unsigned int m;
+	__be32 len;
+
+	/* verify that CCM dimension 'L': 2 <= L <= 8 */
+	if (l < 2 || l > 8)
+		return -EINVAL;
+	if (l < 4 && msglen >> (8 * l))
+		return -EOVERFLOW;
+
+	memset(&req->iv[SM4_BLOCK_SIZE - l], 0, l);
+
+	memcpy(info, req->iv, SM4_BLOCK_SIZE);
+
+	m = crypto_aead_authsize(aead);
+
+	/* format flags field per RFC 3610/NIST 800-38C */
+	*info |= ((m - 2) / 2) << 3;
+	if (req->assoclen)
+		*info |= (1 << 6);
+
+	/*
+	 * format message length field,
+	 * Linux uses a u32 type to represent msglen
+	 */
+	if (l >= 4)
+		l = 4;
+
+	len = cpu_to_be32(msglen);
+	memcpy(&info[SM4_BLOCK_SIZE - l], (u8 *)&len + 4 - l, l);
+
+	return 0;
+}
+
+static void ccm_calculate_auth_mac(struct aead_request *req, u8 mac[])
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct sm4_ctx *ctx = crypto_aead_ctx(aead);
+	struct __packed { __be16 l; __be32 h; } aadlen;
+	u32 assoclen = req->assoclen;
+	struct scatter_walk walk;
+	unsigned int len;
+
+	if (assoclen < 0xff00) {
+		aadlen.l = cpu_to_be16(assoclen);
+		len = 2;
+	} else {
+		aadlen.l = cpu_to_be16(0xfffe);
+		put_unaligned_be32(assoclen, &aadlen.h);
+		len = 6;
+	}
+
+	sm4_ce_crypt_block(ctx->rkey_enc, mac, mac);
+	crypto_xor(mac, (const u8 *)&aadlen, len);
+
+	scatterwalk_start(&walk, req->src);
+
+	do {
+		u32 n = scatterwalk_clamp(&walk, assoclen);
+		u8 *p, *ptr;
+
+		if (!n) {
+			scatterwalk_start(&walk, sg_next(walk.sg));
+			n = scatterwalk_clamp(&walk, assoclen);
+		}
+
+		p = ptr = scatterwalk_map(&walk);
+		assoclen -= n;
+		scatterwalk_advance(&walk, n);
+
+		while (n > 0) {
+			unsigned int l, nblocks;
+
+			if (len == SM4_BLOCK_SIZE) {
+				if (n < SM4_BLOCK_SIZE) {
+					sm4_ce_crypt_block(ctx->rkey_enc,
+							   mac, mac);
+
+					len = 0;
+				} else {
+					nblocks = n / SM4_BLOCK_SIZE;
+					sm4_ce_cbcmac_update(ctx->rkey_enc,
+							     mac, ptr, nblocks);
+
+					ptr += nblocks * SM4_BLOCK_SIZE;
+					n %= SM4_BLOCK_SIZE;
+
+					continue;
+				}
+			}
+
+			l = min(n, SM4_BLOCK_SIZE - len);
+			if (l) {
+				crypto_xor(mac + len, ptr, l);
+				len += l;
+				ptr += l;
+				n -= l;
+			}
+		}
+
+		scatterwalk_unmap(p);
+		scatterwalk_done(&walk, 0, assoclen);
+	} while (assoclen);
+}
+
+static int ccm_crypt(struct aead_request *req, struct skcipher_walk *walk,
+		     u32 *rkey_enc, u8 mac[],
+		     void (*sm4_ce_ccm_crypt)(const u32 *rkey_enc, u8 *dst,
+					const u8 *src, u8 *iv,
+					unsigned int nbytes, u8 *mac))
+{
+	u8 __aligned(8) ctr0[SM4_BLOCK_SIZE];
+	int err;
+
+	/* preserve the initial ctr0 for the TAG */
+	memcpy(ctr0, walk->iv, SM4_BLOCK_SIZE);
+	crypto_inc(walk->iv, SM4_BLOCK_SIZE);
+
+	kernel_neon_begin();
+
+	if (req->assoclen)
+		ccm_calculate_auth_mac(req, mac);
+
+	do {
+		unsigned int tail = walk->nbytes % SM4_BLOCK_SIZE;
+		const u8 *src = walk->src.virt.addr;
+		u8 *dst = walk->dst.virt.addr;
+
+		if (walk->nbytes == walk->total)
+			tail = 0;
+
+		if (walk->nbytes - tail)
+			sm4_ce_ccm_crypt(rkey_enc, dst, src, walk->iv,
+					 walk->nbytes - tail, mac);
+
+		if (walk->nbytes == walk->total)
+			sm4_ce_ccm_final(rkey_enc, ctr0, mac);
+
+		kernel_neon_end();
+
+		if (walk->nbytes) {
+			err = skcipher_walk_done(walk, tail);
+			if (err)
+				return err;
+			if (walk->nbytes)
+				kernel_neon_begin();
+		}
+	} while (walk->nbytes > 0);
+
+	return 0;
+}
+
+static int ccm_encrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct sm4_ctx *ctx = crypto_aead_ctx(aead);
+	u8 __aligned(8) mac[SM4_BLOCK_SIZE];
+	struct skcipher_walk walk;
+	int err;
+
+	err = ccm_format_input(mac, req, req->cryptlen);
+	if (err)
+		return err;
+
+	err = skcipher_walk_aead_encrypt(&walk, req, false);
+	if (err)
+		return err;
+
+	err = ccm_crypt(req, &walk, ctx->rkey_enc, mac, sm4_ce_ccm_enc);
+	if (err)
+		return err;
+
+	/* copy authtag to end of dst */
+	scatterwalk_map_and_copy(mac, req->dst, req->assoclen + req->cryptlen,
+				 crypto_aead_authsize(aead), 1);
+
+	return 0;
+}
+
+static int ccm_decrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	unsigned int authsize = crypto_aead_authsize(aead);
+	struct sm4_ctx *ctx = crypto_aead_ctx(aead);
+	u8 __aligned(8) mac[SM4_BLOCK_SIZE];
+	u8 authtag[SM4_BLOCK_SIZE];
+	struct skcipher_walk walk;
+	int err;
+
+	err = ccm_format_input(mac, req, req->cryptlen - authsize);
+	if (err)
+		return err;
+
+	err = skcipher_walk_aead_decrypt(&walk, req, false);
+	if (err)
+		return err;
+
+	err = ccm_crypt(req, &walk, ctx->rkey_enc, mac, sm4_ce_ccm_dec);
+	if (err)
+		return err;
+
+	/* compare calculated auth tag with the stored one */
+	scatterwalk_map_and_copy(authtag, req->src,
+				 req->assoclen + req->cryptlen - authsize,
+				 authsize, 0);
+
+	if (crypto_memneq(authtag, mac, authsize))
+		return -EBADMSG;
+
+	return 0;
+}
+
+static struct aead_alg sm4_ccm_alg = {
+	.base = {
+		.cra_name		= "ccm(sm4)",
+		.cra_driver_name	= "ccm-sm4-ce",
+		.cra_priority		= 400,
+		.cra_blocksize		= 1,
+		.cra_ctxsize		= sizeof(struct sm4_ctx),
+		.cra_module		= THIS_MODULE,
+	},
+	.ivsize		= SM4_BLOCK_SIZE,
+	.chunksize	= SM4_BLOCK_SIZE,
+	.maxauthsize	= SM4_BLOCK_SIZE,
+	.setkey		= ccm_setkey,
+	.setauthsize	= ccm_setauthsize,
+	.encrypt	= ccm_encrypt,
+	.decrypt	= ccm_decrypt,
+};
+
+static int __init sm4_ce_ccm_init(void)
+{
+	return crypto_register_aead(&sm4_ccm_alg);
+}
+
+static void __exit sm4_ce_ccm_exit(void)
+{
+	crypto_unregister_aead(&sm4_ccm_alg);
+}
+
+module_cpu_feature_match(SM4, sm4_ce_ccm_init);
+module_exit(sm4_ce_ccm_exit);
+
+MODULE_DESCRIPTION("Synchronous SM4 in CCM mode using ARMv8 Crypto Extensions");
+MODULE_ALIAS_CRYPTO("ccm(sm4)");
+MODULE_AUTHOR("Tianjia Zhang <tianjia.zhang@linux.alibaba.com>");
+MODULE_LICENSE("GPL v2");