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

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

Benchmark on T-Head Yitian-710 2.75 GHz, the data comes from the 224 and 224
modes of tcrypt, and compared the performance before and after this patch (the
driver used before this patch is gcm_base(ctr-sm4-ce,ghash-generic)).
The abscissas are blocks of different lengths. The data is tabulated and the
unit is Mb/s:

Before (gcm_base(ctr-sm4-ce,ghash-generic)):

gcm(sm4) | 16 64 256 512 1024 1420 4096 8192
-------------+---------------------------------------------------------------------
GCM enc | 25.24 64.65 104.66 116.69 123.81 125.12 129.67 130.62
GCM dec | 25.40 64.80 104.74 116.70 123.81 125.21 129.68 130.59
GCM mb enc | 24.95 64.06 104.20 116.38 123.55 124.97 129.63 130.61
GCM mb dec | 24.92 64.00 104.13 116.34 123.55 124.98 129.56 130.48

After:

gcm-sm4-ce | 16 64 256 512 1024 1420 4096 8192
-------------+---------------------------------------------------------------------
GCM enc | 108.62 397.18 971.60 1283.92 1522.77 1513.39 1777.00 1806.96
GCM dec | 116.36 398.14 1004.27 1319.11 1624.21 1635.43 1932.54 1974.20
GCM mb enc | 107.13 391.79 962.05 1274.94 1514.76 1508.57 1769.07 1801.58
GCM mb dec | 113.40 389.36 988.51 1307.68 1619.10 1631.55 1931.70 1970.86

Signed-off-by: Tianjia Zhang <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

arch/arm64/crypto/Kconfig

···
 	  - ARMv8 Crypto Extensions
 	  - NEON (Advanced SIMD) extensions
 
+config CRYPTO_SM4_ARM64_CE_GCM
+	tristate "AEAD cipher: SM4 in GCM mode (ARMv8 Crypto Extensions)"
+	depends on KERNEL_MODE_NEON
+	select CRYPTO_ALGAPI
+	select CRYPTO_AEAD
+	select CRYPTO_SM4
+	select CRYPTO_SM4_ARM64_CE_BLK
+	help
+	  AEAD cipher: SM4 cipher algorithms (OSCCA GB/T 32907-2016) with
+	  GCM (Galois/Counter Mode) authenticated encryption mode (NIST SP800-38D)
+
+	  Architecture: arm64 using:
+	  - ARMv8 Crypto Extensions
+	  - PMULL (Polynomial Multiply Long) instructions
+	  - NEON (Advanced SIMD) extensions
+
 config CRYPTO_CRCT10DIF_ARM64_CE
 	tristate "CRCT10DIF (PMULL)"
 	depends on KERNEL_MODE_NEON && CRC_T10DIF

arch/arm64/crypto/Makefile

···
 obj-$(CONFIG_CRYPTO_SM4_ARM64_CE_CCM) += sm4-ce-ccm.o
 sm4-ce-ccm-y := sm4-ce-ccm-glue.o sm4-ce-ccm-core.o
 
+obj-$(CONFIG_CRYPTO_SM4_ARM64_CE_GCM) += sm4-ce-gcm.o
+sm4-ce-gcm-y := sm4-ce-gcm-glue.o sm4-ce-gcm-core.o
+
 obj-$(CONFIG_CRYPTO_SM4_ARM64_NEON_BLK) += sm4-neon.o
 sm4-neon-y := sm4-neon-glue.o sm4-neon-core.o
 

arch/arm64/crypto/sm4-ce-gcm-core.S

···
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * SM4-GCM AEAD Algorithm using ARMv8 Crypto Extensions
+ * as specified in rfc8998
+ * https://datatracker.ietf.org/doc/html/rfc8998
+ *
+ * Copyright (C) 2016 Jussi Kivilinna <[e-mail]>
+ * Copyright (C) 2022 Tianjia Zhang <[e-mail]>
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include "sm4-ce-asm.h"
+
+.arch	armv8-a+crypto
+
+.irp b, 0, 1, 2, 3, 24, 25, 26, 27, 28, 29, 30, 31
+	.set .Lv\b\().4s, \b
+.endr
+
+.macro sm4e, vd, vn
+	.inst 0xcec08400 | (.L\vn << 5) | .L\vd
+.endm
+
+/* Register macros */
+
+/* Used for both encryption and decryption */
+#define	RHASH	v21
+#define	RRCONST	v22
+#define RZERO	v23
+
+/* Helper macros. */
+
+/*
+ * input: m0, m1
+ * output: r0:r1 (low 128-bits in r0, high in r1)
+ */
+#define PMUL_128x128(r0, r1, m0, m1, T0, T1)			\
+		ext		T0.16b, m1.16b, m1.16b, #8;	\
+		pmull		r0.1q, m0.1d, m1.1d;		\
+		pmull		T1.1q, m0.1d, T0.1d;		\
+		pmull2		T0.1q, m0.2d, T0.2d;		\
+		pmull2		r1.1q, m0.2d, m1.2d;		\
+		eor		T0.16b, T0.16b, T1.16b;		\
+		ext		T1.16b, RZERO.16b, T0.16b, #8;	\
+		ext		T0.16b, T0.16b, RZERO.16b, #8;	\
+		eor		r0.16b, r0.16b, T1.16b;		\
+		eor		r1.16b, r1.16b, T0.16b;
+
+#define PMUL_128x128_4x(r0, r1, m0, m1, T0, T1,			\
+			r2, r3, m2, m3, T2, T3,			\
+			r4, r5, m4, m5, T4, T5,			\
+			r6, r7, m6, m7, T6, T7)			\
+		ext		T0.16b, m1.16b, m1.16b, #8;	\
+		ext		T2.16b, m3.16b, m3.16b, #8;	\
+		ext		T4.16b, m5.16b, m5.16b, #8;	\
+		ext		T6.16b, m7.16b, m7.16b, #8;	\
+		pmull		r0.1q, m0.1d, m1.1d;		\
+		pmull		r2.1q, m2.1d, m3.1d;		\
+		pmull		r4.1q, m4.1d, m5.1d;		\
+		pmull		r6.1q, m6.1d, m7.1d;		\
+		pmull		T1.1q, m0.1d, T0.1d;		\
+		pmull		T3.1q, m2.1d, T2.1d;		\
+		pmull		T5.1q, m4.1d, T4.1d;		\
+		pmull		T7.1q, m6.1d, T6.1d;		\
+		pmull2		T0.1q, m0.2d, T0.2d;		\
+		pmull2		T2.1q, m2.2d, T2.2d;		\
+		pmull2		T4.1q, m4.2d, T4.2d;		\
+		pmull2		T6.1q, m6.2d, T6.2d;		\
+		pmull2		r1.1q, m0.2d, m1.2d;		\
+		pmull2		r3.1q, m2.2d, m3.2d;		\
+		pmull2		r5.1q, m4.2d, m5.2d;		\
+		pmull2		r7.1q, m6.2d, m7.2d;		\
+		eor		T0.16b, T0.16b, T1.16b;		\
+		eor		T2.16b, T2.16b, T3.16b;		\
+		eor		T4.16b, T4.16b, T5.16b;		\
+		eor		T6.16b, T6.16b, T7.16b;		\
+		ext		T1.16b, RZERO.16b, T0.16b, #8;	\
+		ext		T3.16b, RZERO.16b, T2.16b, #8;	\
+		ext		T5.16b, RZERO.16b, T4.16b, #8;	\
+		ext		T7.16b, RZERO.16b, T6.16b, #8;	\
+		ext		T0.16b, T0.16b, RZERO.16b, #8;	\
+		ext		T2.16b, T2.16b, RZERO.16b, #8;	\
+		ext		T4.16b, T4.16b, RZERO.16b, #8;	\
+		ext		T6.16b, T6.16b, RZERO.16b, #8;	\
+		eor		r0.16b, r0.16b, T1.16b;		\
+		eor		r2.16b, r2.16b, T3.16b; 	\
+		eor		r4.16b, r4.16b, T5.16b; 	\
+		eor		r6.16b, r6.16b, T7.16b; 	\
+		eor		r1.16b, r1.16b, T0.16b; 	\
+		eor		r3.16b, r3.16b, T2.16b; 	\
+		eor		r5.16b, r5.16b, T4.16b; 	\
+		eor		r7.16b, r7.16b, T6.16b;
+
+/*
+ * input: r0:r1 (low 128-bits in r0, high in r1)
+ * output: a
+ */
+#define REDUCTION(a, r0, r1, rconst, T0, T1)			\
+		pmull2		T0.1q, r1.2d, rconst.2d;	\
+		ext		T1.16b, T0.16b, RZERO.16b, #8;	\
+		ext		T0.16b, RZERO.16b, T0.16b, #8;	\
+		eor		r1.16b, r1.16b, T1.16b;		\
+		eor		r0.16b, r0.16b, T0.16b;		\
+		pmull		T0.1q, r1.1d, rconst.1d;	\
+		eor		a.16b, r0.16b, T0.16b;
+
+#define SM4_CRYPT_PMUL_128x128_BLK(b0, r0, r1, m0, m1, T0, T1)	\
+	rev32			b0.16b, b0.16b;			\
+		ext		T0.16b, m1.16b, m1.16b, #8;	\
+	sm4e			b0.4s, v24.4s;			\
+		pmull		r0.1q, m0.1d, m1.1d;		\
+	sm4e			b0.4s, v25.4s;			\
+		pmull		T1.1q, m0.1d, T0.1d;		\
+	sm4e			b0.4s, v26.4s;			\
+		pmull2		T0.1q, m0.2d, T0.2d;		\
+	sm4e			b0.4s, v27.4s;			\
+		pmull2		r1.1q, m0.2d, m1.2d;		\
+	sm4e			b0.4s, v28.4s;			\
+		eor		T0.16b, T0.16b, T1.16b;		\
+	sm4e			b0.4s, v29.4s;			\
+		ext		T1.16b, RZERO.16b, T0.16b, #8;	\
+	sm4e			b0.4s, v30.4s;			\
+		ext		T0.16b, T0.16b, RZERO.16b, #8;	\
+	sm4e			b0.4s, v31.4s;			\
+		eor		r0.16b, r0.16b, T1.16b;		\
+	rev64			b0.4s, b0.4s;			\
+		eor		r1.16b, r1.16b, T0.16b;		\
+	ext			b0.16b, b0.16b, b0.16b, #8;	\
+	rev32			b0.16b, b0.16b;
+
+#define SM4_CRYPT_PMUL_128x128_BLK3(b0, b1, b2,			\
+				    r0, r1, m0, m1, T0, T1,	\
+				    r2, r3, m2, m3, T2, T3,	\
+				    r4, r5, m4, m5, T4, T5)	\
+	rev32			b0.16b, b0.16b;			\
+	rev32			b1.16b, b1.16b;			\
+	rev32			b2.16b, b2.16b;			\
+		ext		T0.16b, m1.16b, m1.16b, #8;	\
+		ext		T2.16b, m3.16b, m3.16b, #8;	\
+		ext		T4.16b, m5.16b, m5.16b, #8;	\
+	sm4e			b0.4s, v24.4s;			\
+	sm4e			b1.4s, v24.4s;			\
+	sm4e			b2.4s, v24.4s;			\
+		pmull		r0.1q, m0.1d, m1.1d;		\
+		pmull		r2.1q, m2.1d, m3.1d;		\
+		pmull		r4.1q, m4.1d, m5.1d;		\
+	sm4e			b0.4s, v25.4s;			\
+	sm4e			b1.4s, v25.4s;			\
+	sm4e			b2.4s, v25.4s;			\
+		pmull		T1.1q, m0.1d, T0.1d;		\
+		pmull		T3.1q, m2.1d, T2.1d;		\
+		pmull		T5.1q, m4.1d, T4.1d;		\
+	sm4e			b0.4s, v26.4s;			\
+	sm4e			b1.4s, v26.4s;			\
+	sm4e			b2.4s, v26.4s;			\
+		pmull2		T0.1q, m0.2d, T0.2d;		\
+		pmull2		T2.1q, m2.2d, T2.2d;		\
+		pmull2		T4.1q, m4.2d, T4.2d;		\
+	sm4e			b0.4s, v27.4s;			\
+	sm4e			b1.4s, v27.4s;			\
+	sm4e			b2.4s, v27.4s;			\
+		pmull2		r1.1q, m0.2d, m1.2d;		\
+		pmull2		r3.1q, m2.2d, m3.2d;		\
+		pmull2		r5.1q, m4.2d, m5.2d;		\
+	sm4e			b0.4s, v28.4s;			\
+	sm4e			b1.4s, v28.4s;			\
+	sm4e			b2.4s, v28.4s;			\
+		eor		T0.16b, T0.16b, T1.16b;		\
+		eor		T2.16b, T2.16b, T3.16b;		\
+		eor		T4.16b, T4.16b, T5.16b;		\
+	sm4e			b0.4s, v29.4s;			\
+	sm4e			b1.4s, v29.4s;			\
+	sm4e			b2.4s, v29.4s;			\
+		ext		T1.16b, RZERO.16b, T0.16b, #8;	\
+		ext		T3.16b, RZERO.16b, T2.16b, #8;	\
+		ext		T5.16b, RZERO.16b, T4.16b, #8;	\
+	sm4e			b0.4s, v30.4s;			\
+	sm4e			b1.4s, v30.4s;			\
+	sm4e			b2.4s, v30.4s;			\
+		ext		T0.16b, T0.16b, RZERO.16b, #8;	\
+		ext		T2.16b, T2.16b, RZERO.16b, #8;	\
+		ext		T4.16b, T4.16b, RZERO.16b, #8;	\
+	sm4e			b0.4s, v31.4s;			\
+	sm4e			b1.4s, v31.4s;			\
+	sm4e			b2.4s, v31.4s;			\
+		eor		r0.16b, r0.16b, T1.16b;		\
+		eor		r2.16b, r2.16b, T3.16b;		\
+		eor		r4.16b, r4.16b, T5.16b;		\
+	rev64			b0.4s, b0.4s;			\
+	rev64			b1.4s, b1.4s;			\
+	rev64			b2.4s, b2.4s;			\
+		eor		r1.16b, r1.16b, T0.16b;		\
+		eor		r3.16b, r3.16b, T2.16b;		\
+		eor		r5.16b, r5.16b, T4.16b;		\
+	ext			b0.16b, b0.16b, b0.16b, #8;	\
+	ext			b1.16b, b1.16b, b1.16b, #8;	\
+	ext			b2.16b, b2.16b, b2.16b, #8;	\
+		eor		r0.16b, r0.16b, r2.16b;		\
+		eor		r1.16b, r1.16b, r3.16b;		\
+	rev32			b0.16b, b0.16b;			\
+	rev32			b1.16b, b1.16b;			\
+	rev32			b2.16b, b2.16b;			\
+		eor		r0.16b, r0.16b, r4.16b;		\
+		eor		r1.16b, r1.16b, r5.16b;
+
+#define inc32_le128(vctr)					\
+		mov		vctr.d[1], x9;			\
+		add		w6, w9, #1;			\
+		mov		vctr.d[0], x8;			\
+		bfi		x9, x6, #0, #32;		\
+		rev64		vctr.16b, vctr.16b;
+
+#define GTAG_HASH_LENGTHS(vctr0, vlen)					\
+		ld1		{vlen.16b}, [x7];			\
+		/* construct CTR0 */					\
+		/* the lower 32-bits of initial IV is always be32(1) */	\
+		mov		x6, #0x1;				\
+		bfi		x9, x6, #0, #32;			\
+		mov		vctr0.d[0], x8;				\
+		mov		vctr0.d[1], x9;				\
+		rbit		vlen.16b, vlen.16b;			\
+		rev64		vctr0.16b, vctr0.16b;			\
+		/* authtag = GCTR(CTR0, GHASH) */			\
+		eor		RHASH.16b, RHASH.16b, vlen.16b;		\
+		SM4_CRYPT_PMUL_128x128_BLK(vctr0, RR0, RR1, RHASH, RH1,	\
+					   RTMP0, RTMP1);		\
+		REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3);	\
+		rbit		RHASH.16b, RHASH.16b;			\
+		eor		RHASH.16b, RHASH.16b, vctr0.16b;
+
+
+/* Register macros for encrypt and ghash */
+
+/* can be the same as input v0-v3 */
+#define	RR1	v0
+#define	RR3	v1
+#define	RR5	v2
+#define	RR7	v3
+
+#define	RR0	v4
+#define	RR2	v5
+#define	RR4	v6
+#define	RR6	v7
+
+#define RTMP0	v8
+#define RTMP1	v9
+#define RTMP2	v10
+#define RTMP3	v11
+#define RTMP4	v12
+#define RTMP5	v13
+#define RTMP6	v14
+#define RTMP7	v15
+
+#define	RH1	v16
+#define	RH2	v17
+#define	RH3	v18
+#define	RH4	v19
+
+.align 3
+SYM_FUNC_START(sm4_ce_pmull_ghash_setup)
+	/* input:
+	 *   x0: round key array, CTX
+	 *   x1: ghash table
+	 */
+	SM4_PREPARE(x0)
+
+	adr_l		x2, .Lghash_rconst
+	ld1r		{RRCONST.2d}, [x2]
+
+	eor		RZERO.16b, RZERO.16b, RZERO.16b
+
+	/* H = E(K, 0^128) */
+	rev32		v0.16b, RZERO.16b
+	SM4_CRYPT_BLK_BE(v0)
+
+	/* H ^ 1 */
+	rbit		RH1.16b, v0.16b
+
+	/* H ^ 2 */
+	PMUL_128x128(RR0, RR1, RH1, RH1, RTMP0, RTMP1)
+	REDUCTION(RH2, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	/* H ^ 3 */
+	PMUL_128x128(RR0, RR1, RH2, RH1, RTMP0, RTMP1)
+	REDUCTION(RH3, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	/* H ^ 4 */
+	PMUL_128x128(RR0, RR1, RH2, RH2, RTMP0, RTMP1)
+	REDUCTION(RH4, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	st1		{RH1.16b-RH4.16b}, [x1]
+
+	ret
+SYM_FUNC_END(sm4_ce_pmull_ghash_setup)
+
+.align 3
+SYM_FUNC_START(pmull_ghash_update)
+	/* input:
+	 *   x0: ghash table
+	 *   x1: ghash result
+	 *   x2: src
+	 *   w3: nblocks
+	 */
+	ld1		{RH1.16b-RH4.16b}, [x0]
+
+	ld1		{RHASH.16b}, [x1]
+	rbit		RHASH.16b, RHASH.16b
+
+	adr_l		x4, .Lghash_rconst
+	ld1r		{RRCONST.2d}, [x4]
+
+	eor		RZERO.16b, RZERO.16b, RZERO.16b
+
+.Lghash_loop_4x:
+	cmp		w3, #4
+	blt		.Lghash_loop_1x
+
+	sub		w3, w3, #4
+
+	ld1		{v0.16b-v3.16b}, [x2], #64
+
+	rbit		v0.16b, v0.16b
+	rbit		v1.16b, v1.16b
+	rbit		v2.16b, v2.16b
+	rbit		v3.16b, v3.16b
+
+	/*
+	 * (in0 ^ HASH) * H^4 => rr0:rr1
+	 * (in1)        * H^3 => rr2:rr3
+	 * (in2)        * H^2 => rr4:rr5
+	 * (in3)        * H^1 => rr6:rr7
+	 */
+	eor		RHASH.16b, RHASH.16b, v0.16b
+
+	PMUL_128x128_4x(RR0, RR1, RHASH, RH4, RTMP0, RTMP1,
+			RR2, RR3, v1, RH3, RTMP2, RTMP3,
+			RR4, RR5, v2, RH2, RTMP4, RTMP5,
+			RR6, RR7, v3, RH1, RTMP6, RTMP7)
+
+	eor		RR0.16b, RR0.16b, RR2.16b
+	eor		RR1.16b, RR1.16b, RR3.16b
+	eor		RR0.16b, RR0.16b, RR4.16b
+	eor		RR1.16b, RR1.16b, RR5.16b
+	eor		RR0.16b, RR0.16b, RR6.16b
+	eor		RR1.16b, RR1.16b, RR7.16b
+
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP0, RTMP1)
+
+	cbz		w3, .Lghash_end
+	b		.Lghash_loop_4x
+
+.Lghash_loop_1x:
+	sub		w3, w3, #1
+
+	ld1		{v0.16b}, [x2], #16
+	rbit		v0.16b, v0.16b
+	eor		RHASH.16b, RHASH.16b, v0.16b
+
+	PMUL_128x128(RR0, RR1, RHASH, RH1, RTMP0, RTMP1)
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	cbnz		w3, .Lghash_loop_1x
+
+.Lghash_end:
+	rbit		RHASH.16b, RHASH.16b
+	st1		{RHASH.2d}, [x1]
+
+	ret
+SYM_FUNC_END(pmull_ghash_update)
+
+.align 3
+SYM_FUNC_START(sm4_ce_pmull_gcm_enc)
+	/* input:
+	 *   x0: round key array, CTX
+	 *   x1: dst
+	 *   x2: src
+	 *   x3: ctr (big endian, 128 bit)
+	 *   w4: nbytes
+	 *   x5: ghash result
+	 *   x6: ghash table
+	 *   x7: lengths (only for last block)
+	 */
+	SM4_PREPARE(x0)
+
+	ldp		x8, x9, [x3]
+	rev		x8, x8
+	rev		x9, x9
+
+	ld1		{RH1.16b-RH4.16b}, [x6]
+
+	ld1		{RHASH.16b}, [x5]
+	rbit		RHASH.16b, RHASH.16b
+
+	adr_l		x6, .Lghash_rconst
+	ld1r		{RRCONST.2d}, [x6]
+
+	eor		RZERO.16b, RZERO.16b, RZERO.16b
+
+	cbz		w4, .Lgcm_enc_hash_len
+
+.Lgcm_enc_loop_4x:
+	cmp		w4, #(4 * 16)
+	blt		.Lgcm_enc_loop_1x
+
+	sub		w4, w4, #(4 * 16)
+
+	/* construct CTRs */
+	inc32_le128(v0)			/* +0 */
+	inc32_le128(v1)			/* +1 */
+	inc32_le128(v2)			/* +2 */
+	inc32_le128(v3)			/* +3 */
+
+	ld1		{RTMP0.16b-RTMP3.16b}, [x2], #64
+
+	SM4_CRYPT_BLK4(v0, v1, v2, v3)
+
+	eor		v0.16b, v0.16b, RTMP0.16b
+	eor		v1.16b, v1.16b, RTMP1.16b
+	eor		v2.16b, v2.16b, RTMP2.16b
+	eor		v3.16b, v3.16b, RTMP3.16b
+	st1		{v0.16b-v3.16b}, [x1], #64
+
+	/* ghash update */
+
+	rbit		v0.16b, v0.16b
+	rbit		v1.16b, v1.16b
+	rbit		v2.16b, v2.16b
+	rbit		v3.16b, v3.16b
+
+	/*
+	 * (in0 ^ HASH) * H^4 => rr0:rr1
+	 * (in1)        * H^3 => rr2:rr3
+	 * (in2)        * H^2 => rr4:rr5
+	 * (in3)        * H^1 => rr6:rr7
+	 */
+	eor		RHASH.16b, RHASH.16b, v0.16b
+
+	PMUL_128x128_4x(RR0, RR1, RHASH, RH4, RTMP0, RTMP1,
+			RR2, RR3, v1, RH3, RTMP2, RTMP3,
+			RR4, RR5, v2, RH2, RTMP4, RTMP5,
+			RR6, RR7, v3, RH1, RTMP6, RTMP7)
+
+	eor		RR0.16b, RR0.16b, RR2.16b
+	eor		RR1.16b, RR1.16b, RR3.16b
+	eor		RR0.16b, RR0.16b, RR4.16b
+	eor		RR1.16b, RR1.16b, RR5.16b
+	eor		RR0.16b, RR0.16b, RR6.16b
+	eor		RR1.16b, RR1.16b, RR7.16b
+
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP0, RTMP1)
+
+	cbz		w4, .Lgcm_enc_hash_len
+	b		.Lgcm_enc_loop_4x
+
+.Lgcm_enc_loop_1x:
+	cmp		w4, #16
+	blt		.Lgcm_enc_tail
+
+	sub		w4, w4, #16
+
+	/* construct CTRs */
+	inc32_le128(v0)
+
+	ld1		{RTMP0.16b}, [x2], #16
+
+	SM4_CRYPT_BLK(v0)
+
+	eor		v0.16b, v0.16b, RTMP0.16b
+	st1		{v0.16b}, [x1], #16
+
+	/* ghash update */
+	rbit		v0.16b, v0.16b
+	eor		RHASH.16b, RHASH.16b, v0.16b
+	PMUL_128x128(RR0, RR1, RHASH, RH1, RTMP0, RTMP1)
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	cbz		w4, .Lgcm_enc_hash_len
+	b		.Lgcm_enc_loop_1x
+
+.Lgcm_enc_tail:
+	/* construct CTRs */
+	inc32_le128(v0)
+	SM4_CRYPT_BLK(v0)
+
+	/* load permute table */
+	adr_l		x0, .Lcts_permute_table
+	add		x0, x0, #32
+	sub		x0, x0, w4, uxtw
+	ld1		{v3.16b}, [x0]
+
+.Lgcm_enc_tail_loop:
+	/* do encrypt */
+	ldrb		w0, [x2], #1	/* get 1 byte from input */
+	umov		w6, v0.b[0]	/* get top crypted byte */
+	eor		w6, w6, w0	/* w6 = CTR ^ input */
+	strb		w6, [x1], #1	/* store out byte */
+
+	/* shift right out one byte */
+	ext		v0.16b, v0.16b, v0.16b, #1
+	/* the last ciphertext is placed in high bytes */
+	ins		v0.b[15], w6
+
+	subs		w4, w4, #1
+	bne		.Lgcm_enc_tail_loop
+
+	/* padding last block with zeros */
+	tbl		v0.16b, {v0.16b}, v3.16b
+
+	/* ghash update */
+	rbit		v0.16b, v0.16b
+	eor		RHASH.16b, RHASH.16b, v0.16b
+	PMUL_128x128(RR0, RR1, RHASH, RH1, RTMP0, RTMP1)
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+.Lgcm_enc_hash_len:
+	cbz		x7, .Lgcm_enc_end
+
+	GTAG_HASH_LENGTHS(v1, v3)
+
+	b		.Lgcm_enc_ret
+
+.Lgcm_enc_end:
+	/* store new CTR */
+	rev		x8, x8
+	rev		x9, x9
+	stp		x8, x9, [x3]
+
+	rbit		RHASH.16b, RHASH.16b
+
+.Lgcm_enc_ret:
+	/* store new MAC */
+	st1		{RHASH.2d}, [x5]
+
+	ret
+SYM_FUNC_END(sm4_ce_pmull_gcm_enc)
+
+#undef	RR1
+#undef	RR3
+#undef	RR5
+#undef	RR7
+#undef	RR0
+#undef	RR2
+#undef	RR4
+#undef	RR6
+#undef RTMP0
+#undef RTMP1
+#undef RTMP2
+#undef RTMP3
+#undef RTMP4
+#undef RTMP5
+#undef RTMP6
+#undef RTMP7
+#undef	RH1
+#undef	RH2
+#undef	RH3
+#undef	RH4
+
+
+/* Register macros for decrypt */
+
+/* v0-v2 for building CTRs, v3-v5 for saving inputs */
+
+#define	RR1	v6
+#define	RR3	v7
+#define	RR5	v8
+
+#define	RR0	v9
+#define	RR2	v10
+#define	RR4	v11
+
+#define RTMP0	v12
+#define RTMP1	v13
+#define RTMP2	v14
+#define RTMP3	v15
+#define RTMP4	v16
+#define RTMP5	v17
+
+#define	RH1	v18
+#define	RH2	v19
+#define	RH3	v20
+
+.align 3
+SYM_FUNC_START(sm4_ce_pmull_gcm_dec)
+	/* input:
+	 *   x0: round key array, CTX
+	 *   x1: dst
+	 *   x2: src
+	 *   x3: ctr (big endian, 128 bit)
+	 *   w4: nbytes
+	 *   x5: ghash result
+	 *   x6: ghash table
+	 *   x7: lengths (only for last block)
+	 */
+	SM4_PREPARE(x0)
+
+	ldp		x8, x9, [x3]
+	rev		x8, x8
+	rev		x9, x9
+
+	ld1		{RH1.16b-RH3.16b}, [x6]
+
+	ld1		{RHASH.16b}, [x5]
+	rbit		RHASH.16b, RHASH.16b
+
+	adr_l		x6, .Lghash_rconst
+	ld1r		{RRCONST.2d}, [x6]
+
+	eor		RZERO.16b, RZERO.16b, RZERO.16b
+
+	cbz		w4, .Lgcm_dec_hash_len
+
+.Lgcm_dec_loop_3x:
+	cmp		w4, #(3 * 16)
+	blt		.Lgcm_dec_loop_1x
+
+	sub		w4, w4, #(3 * 16)
+
+	ld1		{v3.16b-v5.16b}, [x2], #(3 * 16)
+
+	/* construct CTRs */
+	inc32_le128(v0)			/* +0 */
+	rbit		v6.16b, v3.16b
+	inc32_le128(v1)			/* +1 */
+	rbit		v7.16b, v4.16b
+	inc32_le128(v2)			/* +2 */
+	rbit		v8.16b, v5.16b
+
+	eor		RHASH.16b, RHASH.16b, v6.16b
+
+	/* decrypt & ghash update */
+	SM4_CRYPT_PMUL_128x128_BLK3(v0, v1, v2,
+				    RR0, RR1, RHASH, RH3, RTMP0, RTMP1,
+				    RR2, RR3, v7, RH2, RTMP2, RTMP3,
+				    RR4, RR5, v8, RH1, RTMP4, RTMP5)
+
+	eor		v0.16b, v0.16b, v3.16b
+	eor		v1.16b, v1.16b, v4.16b
+	eor		v2.16b, v2.16b, v5.16b
+
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP0, RTMP1)
+
+	st1		{v0.16b-v2.16b}, [x1], #(3 * 16)
+
+	cbz		w4, .Lgcm_dec_hash_len
+	b		.Lgcm_dec_loop_3x
+
+.Lgcm_dec_loop_1x:
+	cmp		w4, #16
+	blt		.Lgcm_dec_tail
+
+	sub		w4, w4, #16
+
+	ld1		{v3.16b}, [x2], #16
+
+	/* construct CTRs */
+	inc32_le128(v0)
+	rbit		v6.16b, v3.16b
+
+	eor		RHASH.16b, RHASH.16b, v6.16b
+
+	SM4_CRYPT_PMUL_128x128_BLK(v0, RR0, RR1, RHASH, RH1, RTMP0, RTMP1)
+
+	eor		v0.16b, v0.16b, v3.16b
+
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+	st1		{v0.16b}, [x1], #16
+
+	cbz		w4, .Lgcm_dec_hash_len
+	b		.Lgcm_dec_loop_1x
+
+.Lgcm_dec_tail:
+	/* construct CTRs */
+	inc32_le128(v0)
+	SM4_CRYPT_BLK(v0)
+
+	/* load permute table */
+	adr_l		x0, .Lcts_permute_table
+	add		x0, x0, #32
+	sub		x0, x0, w4, uxtw
+	ld1		{v3.16b}, [x0]
+
+.Lgcm_dec_tail_loop:
+	/* do decrypt */
+	ldrb		w0, [x2], #1	/* get 1 byte from input */
+	umov		w6, v0.b[0]	/* get top crypted byte */
+	eor		w6, w6, w0	/* w6 = CTR ^ input */
+	strb		w6, [x1], #1	/* store out byte */
+
+	/* shift right out one byte */
+	ext		v0.16b, v0.16b, v0.16b, #1
+	/* the last ciphertext is placed in high bytes */
+	ins		v0.b[15], w0
+
+	subs		w4, w4, #1
+	bne		.Lgcm_dec_tail_loop
+
+	/* padding last block with zeros */
+	tbl		v0.16b, {v0.16b}, v3.16b
+
+	/* ghash update */
+	rbit		v0.16b, v0.16b
+	eor		RHASH.16b, RHASH.16b, v0.16b
+	PMUL_128x128(RR0, RR1, RHASH, RH1, RTMP0, RTMP1)
+	REDUCTION(RHASH, RR0, RR1, RRCONST, RTMP2, RTMP3)
+
+.Lgcm_dec_hash_len:
+	cbz		x7, .Lgcm_dec_end
+
+	GTAG_HASH_LENGTHS(v1, v3)
+
+	b		.Lgcm_dec_ret
+
+.Lgcm_dec_end:
+	/* store new CTR */
+	rev		x8, x8
+	rev		x9, x9
+	stp		x8, x9, [x3]
+
+	rbit		RHASH.16b, RHASH.16b
+
+.Lgcm_dec_ret:
+	/* store new MAC */
+	st1		{RHASH.2d}, [x5]
+
+	ret
+SYM_FUNC_END(sm4_ce_pmull_gcm_dec)
+
+	.section	".rodata", "a"
+	.align 4
+.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
+
+.Lghash_rconst:
+	.quad		0x87

arch/arm64/crypto/sm4-ce-gcm-glue.c

···
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * SM4-GCM AEAD Algorithm using ARMv8 Crypto Extensions
+ * as specified in rfc8998
+ * https://datatracker.ietf.org/doc/html/rfc8998
+ *
+ * Copyright (C) 2022 Tianjia Zhang <[e-mail]>
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/kernel.h>
+#include <linux/cpufeature.h>
+#include <asm/neon.h>
+#include <crypto/b128ops.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_pmull_ghash_setup(const u32 *rkey_enc, u8 *ghash_table);
+asmlinkage void pmull_ghash_update(const u8 *ghash_table, u8 *ghash,
+				   const u8 *src, unsigned int nblocks);
+asmlinkage void sm4_ce_pmull_gcm_enc(const u32 *rkey_enc, u8 *dst,
+				     const u8 *src, u8 *iv,
+				     unsigned int nbytes, u8 *ghash,
+				     const u8 *ghash_table, const u8 *lengths);
+asmlinkage void sm4_ce_pmull_gcm_dec(const u32 *rkey_enc, u8 *dst,
+				     const u8 *src, u8 *iv,
+				     unsigned int nbytes, u8 *ghash,
+				     const u8 *ghash_table, const u8 *lengths);
+
+#define GHASH_BLOCK_SIZE	16
+#define GCM_IV_SIZE		12
+
+struct sm4_gcm_ctx {
+	struct sm4_ctx key;
+	u8 ghash_table[16 * 4];
+};
+
+
+static int gcm_setkey(struct crypto_aead *tfm, const u8 *key,
+		      unsigned int key_len)
+{
+	struct sm4_gcm_ctx *ctx = crypto_aead_ctx(tfm);
+
+	if (key_len != SM4_KEY_SIZE)
+		return -EINVAL;
+
+	kernel_neon_begin();
+
+	sm4_ce_expand_key(key, ctx->key.rkey_enc, ctx->key.rkey_dec,
+			  crypto_sm4_fk, crypto_sm4_ck);
+	sm4_ce_pmull_ghash_setup(ctx->key.rkey_enc, ctx->ghash_table);
+
+	kernel_neon_end();
+	return 0;
+}
+
+static int gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+	switch (authsize) {
+	case 4:
+	case 8:
+	case 12 ... 16:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static void gcm_calculate_auth_mac(struct aead_request *req, u8 ghash[])
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct sm4_gcm_ctx *ctx = crypto_aead_ctx(aead);
+	u8 __aligned(8) buffer[GHASH_BLOCK_SIZE];
+	u32 assoclen = req->assoclen;
+	struct scatter_walk walk;
+	unsigned int buflen = 0;
+
+	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);
+
+		if (n + buflen < GHASH_BLOCK_SIZE) {
+			memcpy(&buffer[buflen], ptr, n);
+			buflen += n;
+		} else {
+			unsigned int nblocks;
+
+			if (buflen) {
+				unsigned int l = GHASH_BLOCK_SIZE - buflen;
+
+				memcpy(&buffer[buflen], ptr, l);
+				ptr += l;
+				n -= l;
+
+				pmull_ghash_update(ctx->ghash_table, ghash,
+						   buffer, 1);
+			}
+
+			nblocks = n / GHASH_BLOCK_SIZE;
+			if (nblocks) {
+				pmull_ghash_update(ctx->ghash_table, ghash,
+						   ptr, nblocks);
+				ptr += nblocks * GHASH_BLOCK_SIZE;
+			}
+
+			buflen = n % GHASH_BLOCK_SIZE;
+			if (buflen)
+				memcpy(&buffer[0], ptr, buflen);
+		}
+
+		scatterwalk_unmap(p);
+		scatterwalk_done(&walk, 0, assoclen);
+	} while (assoclen);
+
+	/* padding with '0' */
+	if (buflen) {
+		memset(&buffer[buflen], 0, GHASH_BLOCK_SIZE - buflen);
+		pmull_ghash_update(ctx->ghash_table, ghash, buffer, 1);
+	}
+}
+
+static int gcm_crypt(struct aead_request *req, struct skcipher_walk *walk,
+		     struct sm4_gcm_ctx *ctx, u8 ghash[],
+		     void (*sm4_ce_pmull_gcm_crypt)(const u32 *rkey_enc,
+				u8 *dst, const u8 *src, u8 *iv,
+				unsigned int nbytes, u8 *ghash,
+				const u8 *ghash_table, const u8 *lengths))
+{
+	u8 __aligned(8) iv[SM4_BLOCK_SIZE];
+	be128 __aligned(8) lengths;
+	int err;
+
+	memset(ghash, 0, SM4_BLOCK_SIZE);
+
+	lengths.a = cpu_to_be64(req->assoclen * 8);
+	lengths.b = cpu_to_be64(walk->total * 8);
+
+	memcpy(iv, walk->iv, GCM_IV_SIZE);
+	put_unaligned_be32(2, iv + GCM_IV_SIZE);
+
+	kernel_neon_begin();
+
+	if (req->assoclen)
+		gcm_calculate_auth_mac(req, ghash);
+
+	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;
+
+			sm4_ce_pmull_gcm_crypt(ctx->key.rkey_enc, dst, src, iv,
+					       walk->nbytes, ghash,
+					       ctx->ghash_table,
+					       (const u8 *)&lengths);
+		} else if (walk->nbytes - tail) {
+			sm4_ce_pmull_gcm_crypt(ctx->key.rkey_enc, dst, src, iv,
+					       walk->nbytes - tail, ghash,
+					       ctx->ghash_table, NULL);
+		}
+
+		kernel_neon_end();
+
+		err = skcipher_walk_done(walk, tail);
+		if (err)
+			return err;
+		if (walk->nbytes)
+			kernel_neon_begin();
+	} while (walk->nbytes > 0);
+
+	return 0;
+}
+
+static int gcm_encrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct sm4_gcm_ctx *ctx = crypto_aead_ctx(aead);
+	u8 __aligned(8) ghash[SM4_BLOCK_SIZE];
+	struct skcipher_walk walk;
+	int err;
+
+	err = skcipher_walk_aead_encrypt(&walk, req, false);
+	if (err)
+		return err;
+
+	err = gcm_crypt(req, &walk, ctx, ghash, sm4_ce_pmull_gcm_enc);
+	if (err)
+		return err;
+
+	/* copy authtag to end of dst */
+	scatterwalk_map_and_copy(ghash, req->dst, req->assoclen + req->cryptlen,
+				 crypto_aead_authsize(aead), 1);
+
+	return 0;
+}
+
+static int gcm_decrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	unsigned int authsize = crypto_aead_authsize(aead);
+	struct sm4_gcm_ctx *ctx = crypto_aead_ctx(aead);
+	u8 __aligned(8) ghash[SM4_BLOCK_SIZE];
+	u8 authtag[SM4_BLOCK_SIZE];
+	struct skcipher_walk walk;
+	int err;
+
+	err = skcipher_walk_aead_decrypt(&walk, req, false);
+	if (err)
+		return err;
+
+	err = gcm_crypt(req, &walk, ctx, ghash, sm4_ce_pmull_gcm_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, ghash, authsize))
+		return -EBADMSG;
+
+	return 0;
+}
+
+static struct aead_alg sm4_gcm_alg = {
+	.base = {
+		.cra_name		= "gcm(sm4)",
+		.cra_driver_name	= "gcm-sm4-ce",
+		.cra_priority		= 400,
+		.cra_blocksize		= 1,
+		.cra_ctxsize		= sizeof(struct sm4_gcm_ctx),
+		.cra_module		= THIS_MODULE,
+	},
+	.ivsize		= GCM_IV_SIZE,
+	.chunksize	= SM4_BLOCK_SIZE,
+	.maxauthsize	= SM4_BLOCK_SIZE,
+	.setkey		= gcm_setkey,
+	.setauthsize	= gcm_setauthsize,
+	.encrypt	= gcm_encrypt,
+	.decrypt	= gcm_decrypt,
+};
+
+static int __init sm4_ce_gcm_init(void)
+{
+	if (!cpu_have_named_feature(PMULL))
+		return -ENODEV;
+
+	return crypto_register_aead(&sm4_gcm_alg);
+}
+
+static void __exit sm4_ce_gcm_exit(void)
+{
+	crypto_unregister_aead(&sm4_gcm_alg);
+}
+
+static const struct cpu_feature sm4_ce_gcm_cpu_feature[] = {
+	{ cpu_feature(PMULL) },
+	{}
+};
+MODULE_DEVICE_TABLE(cpu, sm4_ce_gcm_cpu_feature);
+
+module_cpu_feature_match(SM4, sm4_ce_gcm_init);
+module_exit(sm4_ce_gcm_exit);
+
+MODULE_DESCRIPTION("Synchronous SM4 in GCM mode using ARMv8 Crypto Extensions");
+MODULE_ALIAS_CRYPTO("gcm(sm4)");
+MODULE_AUTHOR("Tianjia Zhang <[e-mail]>");
+MODULE_LICENSE("GPL v2");