[PATCH v3 09/13] crypto: arm64/sm4 - add CE implementation for CTS-CBC mode

From: Tianjia Zhang
Date: Thu Oct 27 2022 - 02:55:59 EST


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

Benchmark on T-Head Yitian-710 2.75 GHz, the data comes from the 218 mode of
tcrypt, and compared the performance before and after this patch (the driver
used before this patch is cts(cbc-sm4-ce)). The abscissas are blocks of
different lengths. The data is tabulated and the unit is Mb/s:

Before:

cts(cbc-sm4-ce) | 16 64 128 256 1024 1420 4096
----------------+--------------------------------------------------------------
CTS-CBC enc | 286.09 297.17 457.97 627.75 868.58 900.80 957.69
CTS-CBC dec | 286.67 285.63 538.35 947.08 2241.03 2577.32 3391.14

After:

cts-cbc-sm4-ce | 16 64 128 256 1024 1420 4096
----------------+--------------------------------------------------------------
CTS-CBC enc | 288.19 428.80 593.57 741.04 911.73 931.80 950.00
CTS-CBC dec | 292.22 468.99 838.23 1380.76 2741.17 3036.42 3409.62

Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
---
arch/arm64/crypto/sm4-ce-core.S | 102 ++++++++++++++++++++++++++++++++
arch/arm64/crypto/sm4-ce-glue.c | 94 +++++++++++++++++++++++++++++
2 files changed, 196 insertions(+)

diff --git a/arch/arm64/crypto/sm4-ce-core.S b/arch/arm64/crypto/sm4-ce-core.S
index 9e4b4f01cdf3..414d29f8110b 100644
--- a/arch/arm64/crypto/sm4-ce-core.S
+++ b/arch/arm64/crypto/sm4-ce-core.S
@@ -306,6 +306,100 @@ SYM_FUNC_START(sm4_ce_cbc_dec)
ret
SYM_FUNC_END(sm4_ce_cbc_dec)

+.align 3
+SYM_FUNC_START(sm4_ce_cbc_cts_enc)
+ /* input:
+ * x0: round key array, CTX
+ * x1: dst
+ * x2: src
+ * x3: iv (big endian, 128 bit)
+ * w4: nbytes
+ */
+ SM4_PREPARE(x0)
+
+ sub w5, w4, #16
+ uxtw x5, w5
+
+ ld1 {RIV.16b}, [x3]
+
+ ld1 {v0.16b}, [x2]
+ eor RIV.16b, RIV.16b, v0.16b
+ SM4_CRYPT_BLK(RIV)
+
+ /* load permute table */
+ adr_l x6, .Lcts_permute_table
+ add x7, x6, #32
+ add x6, x6, x5
+ sub x7, x7, x5
+ ld1 {v3.16b}, [x6]
+ ld1 {v4.16b}, [x7]
+
+ /* overlapping loads */
+ add x2, x2, x5
+ ld1 {v1.16b}, [x2]
+
+ /* create Cn from En-1 */
+ tbl v0.16b, {RIV.16b}, v3.16b
+ /* padding Pn with zeros */
+ tbl v1.16b, {v1.16b}, v4.16b
+
+ eor v1.16b, v1.16b, RIV.16b
+ SM4_CRYPT_BLK(v1)
+
+ /* overlapping stores */
+ add x5, x1, x5
+ st1 {v0.16b}, [x5]
+ st1 {v1.16b}, [x1]
+
+ ret
+SYM_FUNC_END(sm4_ce_cbc_cts_enc)
+
+.align 3
+SYM_FUNC_START(sm4_ce_cbc_cts_dec)
+ /* input:
+ * x0: round key array, CTX
+ * x1: dst
+ * x2: src
+ * x3: iv (big endian, 128 bit)
+ * w4: nbytes
+ */
+ SM4_PREPARE(x0)
+
+ sub w5, w4, #16
+ uxtw x5, w5
+
+ ld1 {RIV.16b}, [x3]
+
+ /* load permute table */
+ adr_l x6, .Lcts_permute_table
+ add x7, x6, #32
+ add x6, x6, x5
+ sub x7, x7, x5
+ ld1 {v3.16b}, [x6]
+ ld1 {v4.16b}, [x7]
+
+ /* overlapping loads */
+ ld1 {v0.16b}, [x2], x5
+ ld1 {v1.16b}, [x2]
+
+ SM4_CRYPT_BLK(v0)
+ /* select the first Ln bytes of Xn to create Pn */
+ tbl v2.16b, {v0.16b}, v3.16b
+ eor v2.16b, v2.16b, v1.16b
+
+ /* overwrite the first Ln bytes with Cn to create En-1 */
+ tbx v0.16b, {v1.16b}, v4.16b
+ SM4_CRYPT_BLK(v0)
+ eor v0.16b, v0.16b, RIV.16b
+
+ /* overlapping stores */
+ add x5, x1, x5
+ st1 {v2.16b}, [x5]
+ st1 {v0.16b}, [x1]
+
+ ret
+SYM_FUNC_END(sm4_ce_cbc_cts_dec)
+
.align 3
SYM_FUNC_START(sm4_ce_cfb_enc)
/* input:
@@ -576,3 +670,11 @@ SYM_FUNC_END(sm4_ce_ctr_enc)
.Lbswap128_mask:
.byte 0x0c, 0x0d, 0x0e, 0x0f, 0x08, 0x09, 0x0a, 0x0b
.byte 0x04, 0x05, 0x06, 0x07, 0x00, 0x01, 0x02, 0x03
+
+.Lcts_permute_table:
+ .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+ .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+ .byte 0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7
+ .byte 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf
+ .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+ .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
diff --git a/arch/arm64/crypto/sm4-ce-glue.c b/arch/arm64/crypto/sm4-ce-glue.c
index 63abcadc684b..4d4072c7bfa2 100644
--- a/arch/arm64/crypto/sm4-ce-glue.c
+++ b/arch/arm64/crypto/sm4-ce-glue.c
@@ -16,6 +16,7 @@
#include <asm/simd.h>
#include <crypto/internal/simd.h>
#include <crypto/internal/skcipher.h>
+#include <crypto/scatterwalk.h>
#include <crypto/sm4.h>

#define BYTES2BLKS(nbytes) ((nbytes) >> 4)
@@ -29,6 +30,10 @@ asmlinkage void sm4_ce_cbc_enc(const u32 *rkey, u8 *dst, const u8 *src,
u8 *iv, unsigned int nblocks);
asmlinkage void sm4_ce_cbc_dec(const u32 *rkey, u8 *dst, const u8 *src,
u8 *iv, unsigned int nblocks);
+asmlinkage void sm4_ce_cbc_cts_enc(const u32 *rkey, u8 *dst, const u8 *src,
+ u8 *iv, unsigned int nbytes);
+asmlinkage void sm4_ce_cbc_cts_dec(const u32 *rkey, u8 *dst, const u8 *src,
+ u8 *iv, unsigned int nbytes);
asmlinkage void sm4_ce_cfb_enc(const u32 *rkey, u8 *dst, const u8 *src,
u8 *iv, unsigned int nblks);
asmlinkage void sm4_ce_cfb_dec(const u32 *rkey, u8 *dst, const u8 *src,
@@ -153,6 +158,78 @@ static int sm4_cbc_decrypt(struct skcipher_request *req)
return sm4_cbc_crypt(req, ctx, false);
}

+static int sm4_cbc_cts_crypt(struct skcipher_request *req, bool encrypt)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct sm4_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct scatterlist *src = req->src;
+ struct scatterlist *dst = req->dst;
+ struct scatterlist sg_src[2], sg_dst[2];
+ struct skcipher_request subreq;
+ struct skcipher_walk walk;
+ int cbc_blocks;
+ int err;
+
+ if (req->cryptlen < SM4_BLOCK_SIZE)
+ return -EINVAL;
+
+ if (req->cryptlen == SM4_BLOCK_SIZE)
+ return sm4_cbc_crypt(req, ctx, encrypt);
+
+ skcipher_request_set_tfm(&subreq, tfm);
+ skcipher_request_set_callback(&subreq, skcipher_request_flags(req),
+ NULL, NULL);
+
+ /* handle the CBC cryption part */
+ cbc_blocks = DIV_ROUND_UP(req->cryptlen, SM4_BLOCK_SIZE) - 2;
+ if (cbc_blocks) {
+ skcipher_request_set_crypt(&subreq, src, dst,
+ cbc_blocks * SM4_BLOCK_SIZE,
+ req->iv);
+
+ err = sm4_cbc_crypt(&subreq, ctx, encrypt);
+ if (err)
+ return err;
+
+ dst = src = scatterwalk_ffwd(sg_src, src, subreq.cryptlen);
+ if (req->dst != req->src)
+ dst = scatterwalk_ffwd(sg_dst, req->dst,
+ subreq.cryptlen);
+ }
+
+ /* handle ciphertext stealing */
+ skcipher_request_set_crypt(&subreq, src, dst,
+ req->cryptlen - cbc_blocks * SM4_BLOCK_SIZE,
+ req->iv);
+
+ err = skcipher_walk_virt(&walk, &subreq, false);
+ if (err)
+ return err;
+
+ kernel_neon_begin();
+
+ if (encrypt)
+ sm4_ce_cbc_cts_enc(ctx->rkey_enc, walk.dst.virt.addr,
+ walk.src.virt.addr, walk.iv, walk.nbytes);
+ else
+ sm4_ce_cbc_cts_dec(ctx->rkey_dec, walk.dst.virt.addr,
+ walk.src.virt.addr, walk.iv, walk.nbytes);
+
+ kernel_neon_end();
+
+ return skcipher_walk_done(&walk, 0);
+}
+
+static int sm4_cbc_cts_encrypt(struct skcipher_request *req)
+{
+ return sm4_cbc_cts_crypt(req, true);
+}
+
+static int sm4_cbc_cts_decrypt(struct skcipher_request *req)
+{
+ return sm4_cbc_cts_crypt(req, false);
+}
+
static int sm4_cfb_encrypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
@@ -342,6 +419,22 @@ static struct skcipher_alg sm4_algs[] = {
.setkey = sm4_setkey,
.encrypt = sm4_ctr_crypt,
.decrypt = sm4_ctr_crypt,
+ }, {
+ .base = {
+ .cra_name = "cts(cbc(sm4))",
+ .cra_driver_name = "cts-cbc-sm4-ce",
+ .cra_priority = 400,
+ .cra_blocksize = SM4_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct sm4_ctx),
+ .cra_module = THIS_MODULE,
+ },
+ .min_keysize = SM4_KEY_SIZE,
+ .max_keysize = SM4_KEY_SIZE,
+ .ivsize = SM4_BLOCK_SIZE,
+ .walksize = SM4_BLOCK_SIZE * 2,
+ .setkey = sm4_setkey,
+ .encrypt = sm4_cbc_cts_encrypt,
+ .decrypt = sm4_cbc_cts_decrypt,
}
};

@@ -365,5 +458,6 @@ MODULE_ALIAS_CRYPTO("ecb(sm4)");
MODULE_ALIAS_CRYPTO("cbc(sm4)");
MODULE_ALIAS_CRYPTO("cfb(sm4)");
MODULE_ALIAS_CRYPTO("ctr(sm4)");
+MODULE_ALIAS_CRYPTO("cts(cbc(sm4))");
MODULE_AUTHOR("Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>");
MODULE_LICENSE("GPL v2");
--
2.24.3 (Apple Git-128)