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Diffstat (limited to 'arch/arm64/crypto/speck-neon-core.S')
| -rw-r--r-- | arch/arm64/crypto/speck-neon-core.S | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/arch/arm64/crypto/speck-neon-core.S b/arch/arm64/crypto/speck-neon-core.S new file mode 100644 index 000000000000..b14463438b09 --- /dev/null +++ b/arch/arm64/crypto/speck-neon-core.S @@ -0,0 +1,352 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ARM64 NEON-accelerated implementation of Speck128-XTS and Speck64-XTS + * + * Copyright (c) 2018 Google, Inc + * + * Author: Eric Biggers <ebiggers@google.com> + */ + +#include <linux/linkage.h> + + .text + + // arguments + ROUND_KEYS .req x0 // const {u64,u32} *round_keys + NROUNDS .req w1 // int nrounds + NROUNDS_X .req x1 + DST .req x2 // void *dst + SRC .req x3 // const void *src + NBYTES .req w4 // unsigned int nbytes + TWEAK .req x5 // void *tweak + + // registers which hold the data being encrypted/decrypted + // (underscores avoid a naming collision with ARM64 registers x0-x3) + X_0 .req v0 + Y_0 .req v1 + X_1 .req v2 + Y_1 .req v3 + X_2 .req v4 + Y_2 .req v5 + X_3 .req v6 + Y_3 .req v7 + + // the round key, duplicated in all lanes + ROUND_KEY .req v8 + + // index vector for tbl-based 8-bit rotates + ROTATE_TABLE .req v9 + ROTATE_TABLE_Q .req q9 + + // temporary registers + TMP0 .req v10 + TMP1 .req v11 + TMP2 .req v12 + TMP3 .req v13 + + // multiplication table for updating XTS tweaks + GFMUL_TABLE .req v14 + GFMUL_TABLE_Q .req q14 + + // next XTS tweak value(s) + TWEAKV_NEXT .req v15 + + // XTS tweaks for the blocks currently being encrypted/decrypted + TWEAKV0 .req v16 + TWEAKV1 .req v17 + TWEAKV2 .req v18 + TWEAKV3 .req v19 + TWEAKV4 .req v20 + TWEAKV5 .req v21 + TWEAKV6 .req v22 + TWEAKV7 .req v23 + + .align 4 +.Lror64_8_table: + .octa 0x080f0e0d0c0b0a090007060504030201 +.Lror32_8_table: + .octa 0x0c0f0e0d080b0a090407060500030201 +.Lrol64_8_table: + .octa 0x0e0d0c0b0a09080f0605040302010007 +.Lrol32_8_table: + .octa 0x0e0d0c0f0a09080b0605040702010003 +.Lgf128mul_table: + .octa 0x00000000000000870000000000000001 +.Lgf64mul_table: + .octa 0x0000000000000000000000002d361b00 + +/* + * _speck_round_128bytes() - Speck encryption round on 128 bytes at a time + * + * Do one Speck encryption round on the 128 bytes (8 blocks for Speck128, 16 for + * Speck64) stored in X0-X3 and Y0-Y3, using the round key stored in all lanes + * of ROUND_KEY. 'n' is the lane size: 64 for Speck128, or 32 for Speck64. + * 'lanes' is the lane specifier: "2d" for Speck128 or "4s" for Speck64. + */ +.macro _speck_round_128bytes n, lanes + + // x = ror(x, 8) + tbl X_0.16b, {X_0.16b}, ROTATE_TABLE.16b + tbl X_1.16b, {X_1.16b}, ROTATE_TABLE.16b + tbl X_2.16b, {X_2.16b}, ROTATE_TABLE.16b + tbl X_3.16b, {X_3.16b}, ROTATE_TABLE.16b + + // x += y + add X_0.\lanes, X_0.\lanes, Y_0.\lanes + add X_1.\lanes, X_1.\lanes, Y_1.\lanes + add X_2.\lanes, X_2.\lanes, Y_2.\lanes + add X_3.\lanes, X_3.\lanes, Y_3.\lanes + + // x ^= k + eor X_0.16b, X_0.16b, ROUND_KEY.16b + eor X_1.16b, X_1.16b, ROUND_KEY.16b + eor X_2.16b, X_2.16b, ROUND_KEY.16b + eor X_3.16b, X_3.16b, ROUND_KEY.16b + + // y = rol(y, 3) + shl TMP0.\lanes, Y_0.\lanes, #3 + shl TMP1.\lanes, Y_1.\lanes, #3 + shl TMP2.\lanes, Y_2.\lanes, #3 + shl TMP3.\lanes, Y_3.\lanes, #3 + sri TMP0.\lanes, Y_0.\lanes, #(\n - 3) + sri TMP1.\lanes, Y_1.\lanes, #(\n - 3) + sri TMP2.\lanes, Y_2.\lanes, #(\n - 3) + sri TMP3.\lanes, Y_3.\lanes, #(\n - 3) + + // y ^= x + eor Y_0.16b, TMP0.16b, X_0.16b + eor Y_1.16b, TMP1.16b, X_1.16b + eor Y_2.16b, TMP2.16b, X_2.16b + eor Y_3.16b, TMP3.16b, X_3.16b +.endm + +/* + * _speck_unround_128bytes() - Speck decryption round on 128 bytes at a time + * + * This is the inverse of _speck_round_128bytes(). + */ +.macro _speck_unround_128bytes n, lanes + + // y ^= x + eor TMP0.16b, Y_0.16b, X_0.16b + eor TMP1.16b, Y_1.16b, X_1.16b + eor TMP2.16b, Y_2.16b, X_2.16b + eor TMP3.16b, Y_3.16b, X_3.16b + + // y = ror(y, 3) + ushr Y_0.\lanes, TMP0.\lanes, #3 + ushr Y_1.\lanes, TMP1.\lanes, #3 + ushr Y_2.\lanes, TMP2.\lanes, #3 + ushr Y_3.\lanes, TMP3.\lanes, #3 + sli Y_0.\lanes, TMP0.\lanes, #(\n - 3) + sli Y_1.\lanes, TMP1.\lanes, #(\n - 3) + sli Y_2.\lanes, TMP2.\lanes, #(\n - 3) + sli Y_3.\lanes, TMP3.\lanes, #(\n - 3) + + // x ^= k + eor X_0.16b, X_0.16b, ROUND_KEY.16b + eor X_1.16b, X_1.16b, ROUND_KEY.16b + eor X_2.16b, X_2.16b, ROUND_KEY.16b + eor X_3.16b, X_3.16b, ROUND_KEY.16b + + // x -= y + sub X_0.\lanes, X_0.\lanes, Y_0.\lanes + sub X_1.\lanes, X_1.\lanes, Y_1.\lanes + sub X_2.\lanes, X_2.\lanes, Y_2.\lanes + sub X_3.\lanes, X_3.\lanes, Y_3.\lanes + + // x = rol(x, 8) + tbl X_0.16b, {X_0.16b}, ROTATE_TABLE.16b + tbl X_1.16b, {X_1.16b}, ROTATE_TABLE.16b + tbl X_2.16b, {X_2.16b}, ROTATE_TABLE.16b + tbl X_3.16b, {X_3.16b}, ROTATE_TABLE.16b +.endm + +.macro _next_xts_tweak next, cur, tmp, n +.if \n == 64 + /* + * Calculate the next tweak by multiplying the current one by x, + * modulo p(x) = x^128 + x^7 + x^2 + x + 1. + */ + sshr \tmp\().2d, \cur\().2d, #63 + and \tmp\().16b, \tmp\().16b, GFMUL_TABLE.16b + shl \next\().2d, \cur\().2d, #1 + ext \tmp\().16b, \tmp\().16b, \tmp\().16b, #8 + eor \next\().16b, \next\().16b, \tmp\().16b +.else + /* + * Calculate the next two tweaks by multiplying the current ones by x^2, + * modulo p(x) = x^64 + x^4 + x^3 + x + 1. + */ + ushr \tmp\().2d, \cur\().2d, #62 + shl \next\().2d, \cur\().2d, #2 + tbl \tmp\().16b, {GFMUL_TABLE.16b}, \tmp\().16b + eor \next\().16b, \next\().16b, \tmp\().16b +.endif +.endm + +/* + * _speck_xts_crypt() - Speck-XTS encryption/decryption + * + * Encrypt or decrypt NBYTES bytes of data from the SRC buffer to the DST buffer + * using Speck-XTS, specifically the variant with a block size of '2n' and round + * count given by NROUNDS. The expanded round keys are given in ROUND_KEYS, and + * the current XTS tweak value is given in TWEAK. It's assumed that NBYTES is a + * nonzero multiple of 128. + */ +.macro _speck_xts_crypt n, lanes, decrypting + + /* + * If decrypting, modify the ROUND_KEYS parameter to point to the last + * round key rather than the first, since for decryption the round keys + * are used in reverse order. + */ +.if \decrypting + mov NROUNDS, NROUNDS /* zero the high 32 bits */ +.if \n == 64 + add ROUND_KEYS, ROUND_KEYS, NROUNDS_X, lsl #3 + sub ROUND_KEYS, ROUND_KEYS, #8 +.else + add ROUND_KEYS, ROUND_KEYS, NROUNDS_X, lsl #2 + sub ROUND_KEYS, ROUND_KEYS, #4 +.endif +.endif + + // Load the index vector for tbl-based 8-bit rotates +.if \decrypting + ldr ROTATE_TABLE_Q, .Lrol\n\()_8_table +.else + ldr ROTATE_TABLE_Q, .Lror\n\()_8_table +.endif + + // One-time XTS preparation +.if \n == 64 + // Load first tweak + ld1 {TWEAKV0.16b}, [TWEAK] + + // Load GF(2^128) multiplication table + ldr GFMUL_TABLE_Q, .Lgf128mul_table +.else + // Load first tweak + ld1 {TWEAKV0.8b}, [TWEAK] + + // Load GF(2^64) multiplication table + ldr GFMUL_TABLE_Q, .Lgf64mul_table + + // Calculate second tweak, packing it together with the first + ushr TMP0.2d, TWEAKV0.2d, #63 + shl TMP1.2d, TWEAKV0.2d, #1 + tbl TMP0.8b, {GFMUL_TABLE.16b}, TMP0.8b + eor TMP0.8b, TMP0.8b, TMP1.8b + mov TWEAKV0.d[1], TMP0.d[0] +.endif + +.Lnext_128bytes_\@: + + // Calculate XTS tweaks for next 128 bytes + _next_xts_tweak TWEAKV1, TWEAKV0, TMP0, \n + _next_xts_tweak TWEAKV2, TWEAKV1, TMP0, \n + _next_xts_tweak TWEAKV3, TWEAKV2, TMP0, \n + _next_xts_tweak TWEAKV4, TWEAKV3, TMP0, \n + _next_xts_tweak TWEAKV5, TWEAKV4, TMP0, \n + _next_xts_tweak TWEAKV6, TWEAKV5, TMP0, \n + _next_xts_tweak TWEAKV7, TWEAKV6, TMP0, \n + _next_xts_tweak TWEAKV_NEXT, TWEAKV7, TMP0, \n + + // Load the next source blocks into {X,Y}[0-3] + ld1 {X_0.16b-Y_1.16b}, [SRC], #64 + ld1 {X_2.16b-Y_3.16b}, [SRC], #64 + + // XOR the source blocks with their XTS tweaks + eor TMP0.16b, X_0.16b, TWEAKV0.16b + eor Y_0.16b, Y_0.16b, TWEAKV1.16b + eor TMP1.16b, X_1.16b, TWEAKV2.16b + eor Y_1.16b, Y_1.16b, TWEAKV3.16b + eor TMP2.16b, X_2.16b, TWEAKV4.16b + eor Y_2.16b, Y_2.16b, TWEAKV5.16b + eor TMP3.16b, X_3.16b, TWEAKV6.16b + eor Y_3.16b, Y_3.16b, TWEAKV7.16b + + /* + * De-interleave the 'x' and 'y' elements of each block, i.e. make it so + * that the X[0-3] registers contain only the second halves of blocks, + * and the Y[0-3] registers contain only the first halves of blocks. + * (Speck uses the order (y, x) rather than the more intuitive (x, y).) + */ + uzp2 X_0.\lanes, TMP0.\lanes, Y_0.\lanes + uzp1 Y_0.\lanes, TMP0.\lanes, Y_0.\lanes + uzp2 X_1.\lanes, TMP1.\lanes, Y_1.\lanes + uzp1 Y_1.\lanes, TMP1.\lanes, Y_1.\lanes + uzp2 X_2.\lanes, TMP2.\lanes, Y_2.\lanes + uzp1 Y_2.\lanes, TMP2.\lanes, Y_2.\lanes + uzp2 X_3.\lanes, TMP3.\lanes, Y_3.\lanes + uzp1 Y_3.\lanes, TMP3.\lanes, Y_3.\lanes + + // Do the cipher rounds + mov x6, ROUND_KEYS + mov w7, NROUNDS +.Lnext_round_\@: +.if \decrypting + ld1r {ROUND_KEY.\lanes}, [x6] + sub x6, x6, #( \n / 8 ) + _speck_unround_128bytes \n, \lanes +.else + ld1r {ROUND_KEY.\lanes}, [x6], #( \n / 8 ) + _speck_round_128bytes \n, \lanes +.endif + subs w7, w7, #1 + bne .Lnext_round_\@ + + // Re-interleave the 'x' and 'y' elements of each block + zip1 TMP0.\lanes, Y_0.\lanes, X_0.\lanes + zip2 Y_0.\lanes, Y_0.\lanes, X_0.\lanes + zip1 TMP1.\lanes, Y_1.\lanes, X_1.\lanes + zip2 Y_1.\lanes, Y_1.\lanes, X_1.\lanes + zip1 TMP2.\lanes, Y_2.\lanes, X_2.\lanes + zip2 Y_2.\lanes, Y_2.\lanes, X_2.\lanes + zip1 TMP3.\lanes, Y_3.\lanes, X_3.\lanes + zip2 Y_3.\lanes, Y_3.\lanes, X_3.\lanes + + // XOR the encrypted/decrypted blocks with the tweaks calculated earlier + eor X_0.16b, TMP0.16b, TWEAKV0.16b + eor Y_0.16b, Y_0.16b, TWEAKV1.16b + eor X_1.16b, TMP1.16b, TWEAKV2.16b + eor Y_1.16b, Y_1.16b, TWEAKV3.16b + eor X_2.16b, TMP2.16b, TWEAKV4.16b + eor Y_2.16b, Y_2.16b, TWEAKV5.16b + eor X_3.16b, TMP3.16b, TWEAKV6.16b + eor Y_3.16b, Y_3.16b, TWEAKV7.16b + mov TWEAKV0.16b, TWEAKV_NEXT.16b + + // Store the ciphertext in the destination buffer + st1 {X_0.16b-Y_1.16b}, [DST], #64 + st1 {X_2.16b-Y_3.16b}, [DST], #64 + + // Continue if there are more 128-byte chunks remaining + subs NBYTES, NBYTES, #128 + bne .Lnext_128bytes_\@ + + // Store the next tweak and return +.if \n == 64 + st1 {TWEAKV_NEXT.16b}, [TWEAK] +.else + st1 {TWEAKV_NEXT.8b}, [TWEAK] +.endif + ret +.endm + +ENTRY(speck128_xts_encrypt_neon) + _speck_xts_crypt n=64, lanes=2d, decrypting=0 +ENDPROC(speck128_xts_encrypt_neon) + +ENTRY(speck128_xts_decrypt_neon) + _speck_xts_crypt n=64, lanes=2d, decrypting=1 +ENDPROC(speck128_xts_decrypt_neon) + +ENTRY(speck64_xts_encrypt_neon) + _speck_xts_crypt n=32, lanes=4s, decrypting=0 +ENDPROC(speck64_xts_encrypt_neon) + +ENTRY(speck64_xts_decrypt_neon) + _speck_xts_crypt n=32, lanes=4s, decrypting=1 +ENDPROC(speck64_xts_decrypt_neon) |