diff options
Diffstat (limited to 'arch/arm64/crypto/sm4-ce-gcm-core.S')
-rw-r--r-- | arch/arm64/crypto/sm4-ce-gcm-core.S | 741 |
1 files changed, 741 insertions, 0 deletions
diff --git a/arch/arm64/crypto/sm4-ce-gcm-core.S b/arch/arm64/crypto/sm4-ce-gcm-core.S new file mode 100644 index 000000000000..7aa3ec18a289 --- /dev/null +++ b/arch/arm64/crypto/sm4-ce-gcm-core.S @@ -0,0 +1,741 @@ +/* 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 <jussi.kivilinna@iki.fi> + * Copyright (C) 2022 Tianjia Zhang <tianjia.zhang@linux.alibaba.com> + */ + +#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 |