/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * BLAKE2b digest algorithm, NEON accelerated * * Copyright 2020 Google LLC * * Author: Eric Biggers */ #include .text .fpu neon // The arguments to blake2b_compress_neon() STATE .req r0 BLOCK .req r1 NBLOCKS .req r2 INC .req r3 // Pointers to the rotation tables ROR24_TABLE .req r4 ROR16_TABLE .req r5 // The original stack pointer ORIG_SP .req r6 // NEON registers which contain the message words of the current block. // M_0-M_3 are occasionally used for other purposes too. M_0 .req d16 M_1 .req d17 M_2 .req d18 M_3 .req d19 M_4 .req d20 M_5 .req d21 M_6 .req d22 M_7 .req d23 M_8 .req d24 M_9 .req d25 M_10 .req d26 M_11 .req d27 M_12 .req d28 M_13 .req d29 M_14 .req d30 M_15 .req d31 .align 4 // Tables for computing ror64(x, 24) and ror64(x, 16) using the vtbl.8 // instruction. This is the most efficient way to implement these // rotation amounts with NEON. (On Cortex-A53 it's the same speed as // vshr.u64 + vsli.u64, while on Cortex-A7 it's faster.) .Lror24_table: .byte 3, 4, 5, 6, 7, 0, 1, 2 .Lror16_table: .byte 2, 3, 4, 5, 6, 7, 0, 1 // The BLAKE2b initialization vector .Lblake2b_IV: .quad 0x6a09e667f3bcc908, 0xbb67ae8584caa73b .quad 0x3c6ef372fe94f82b, 0xa54ff53a5f1d36f1 .quad 0x510e527fade682d1, 0x9b05688c2b3e6c1f .quad 0x1f83d9abfb41bd6b, 0x5be0cd19137e2179 // Execute one round of BLAKE2b by updating the state matrix v[0..15] in the // NEON registers q0-q7. The message block is in q8..q15 (M_0-M_15). The stack // pointer points to a 32-byte aligned buffer containing a copy of q8 and q9 // (M_0-M_3), so that they can be reloaded if they are used as temporary // registers. The macro arguments s0-s15 give the order in which the message // words are used in this round. 'final' is 1 if this is the final round. .macro _blake2b_round s0, s1, s2, s3, s4, s5, s6, s7, \ s8, s9, s10, s11, s12, s13, s14, s15, final=0 // Mix the columns: // (v[0], v[4], v[8], v[12]), (v[1], v[5], v[9], v[13]), // (v[2], v[6], v[10], v[14]), and (v[3], v[7], v[11], v[15]). // a += b + m[blake2b_sigma[r][2*i + 0]]; vadd.u64 q0, q0, q2 vadd.u64 q1, q1, q3 vadd.u64 d0, d0, M_\s0 vadd.u64 d1, d1, M_\s2 vadd.u64 d2, d2, M_\s4 vadd.u64 d3, d3, M_\s6 // d = ror64(d ^ a, 32); veor q6, q6, q0 veor q7, q7, q1 vrev64.32 q6, q6 vrev64.32 q7, q7 // c += d; vadd.u64 q4, q4, q6 vadd.u64 q5, q5, q7 // b = ror64(b ^ c, 24); vld1.8 {M_0}, [ROR24_TABLE, :64] veor q2, q2, q4 veor q3, q3, q5 vtbl.8 d4, {d4}, M_0 vtbl.8 d5, {d5}, M_0 vtbl.8 d6, {d6}, M_0 vtbl.8 d7, {d7}, M_0 // a += b + m[blake2b_sigma[r][2*i + 1]]; // // M_0 got clobbered above, so we have to reload it if any of the four // message words this step needs happens to be M_0. Otherwise we don't // need to reload it here, as it will just get clobbered again below. .if \s1 == 0 || \s3 == 0 || \s5 == 0 || \s7 == 0 vld1.8 {M_0}, [sp, :64] .endif vadd.u64 q0, q0, q2 vadd.u64 q1, q1, q3 vadd.u64 d0, d0, M_\s1 vadd.u64 d1, d1, M_\s3 vadd.u64 d2, d2, M_\s5 vadd.u64 d3, d3, M_\s7 // d = ror64(d ^ a, 16); vld1.8 {M_0}, [ROR16_TABLE, :64] veor q6, q6, q0 veor q7, q7, q1 vtbl.8 d12, {d12}, M_0 vtbl.8 d13, {d13}, M_0 vtbl.8 d14, {d14}, M_0 vtbl.8 d15, {d15}, M_0 // c += d; vadd.u64 q4, q4, q6 vadd.u64 q5, q5, q7 // b = ror64(b ^ c, 63); // // This rotation amount isn't a multiple of 8, so it has to be // implemented using a pair of shifts, which requires temporary // registers. Use q8-q9 (M_0-M_3) for this, and reload them afterwards. veor q8, q2, q4 veor q9, q3, q5 vshr.u64 q2, q8, #63 vshr.u64 q3, q9, #63 vsli.u64 q2, q8, #1 vsli.u64 q3, q9, #1 vld1.8 {q8-q9}, [sp, :256] // Mix the diagonals: // (v[0], v[5], v[10], v[15]), (v[1], v[6], v[11], v[12]), // (v[2], v[7], v[8], v[13]), and (v[3], v[4], v[9], v[14]). // // There are two possible ways to do this: use 'vext' instructions to // shift the rows of the matrix so that the diagonals become columns, // and undo it afterwards; or just use 64-bit operations on 'd' // registers instead of 128-bit operations on 'q' registers. We use the // latter approach, as it performs much better on Cortex-A7. // a += b + m[blake2b_sigma[r][2*i + 0]]; vadd.u64 d0, d0, d5 vadd.u64 d1, d1, d6 vadd.u64 d2, d2, d7 vadd.u64 d3, d3, d4 vadd.u64 d0, d0, M_\s8 vadd.u64 d1, d1, M_\s10 vadd.u64 d2, d2, M_\s12 vadd.u64 d3, d3, M_\s14 // d = ror64(d ^ a, 32); veor d15, d15, d0 veor d12, d12, d1 veor d13, d13, d2 veor d14, d14, d3 vrev64.32 d15, d15 vrev64.32 d12, d12 vrev64.32 d13, d13 vrev64.32 d14, d14 // c += d; vadd.u64 d10, d10, d15 vadd.u64 d11, d11, d12 vadd.u64 d8, d8, d13 vadd.u64 d9, d9, d14 // b = ror64(b ^ c, 24); vld1.8 {M_0}, [ROR24_TABLE, :64] veor d5, d5, d10 veor d6, d6, d11 veor d7, d7, d8 veor d4, d4, d9 vtbl.8 d5, {d5}, M_0 vtbl.8 d6, {d6}, M_0 vtbl.8 d7, {d7}, M_0 vtbl.8 d4, {d4}, M_0 // a += b + m[blake2b_sigma[r][2*i + 1]]; .if \s9 == 0 || \s11 == 0 || \s13 == 0 || \s15 == 0 vld1.8 {M_0}, [sp, :64] .endif vadd.u64 d0, d0, d5 vadd.u64 d1, d1, d6 vadd.u64 d2, d2, d7 vadd.u64 d3, d3, d4 vadd.u64 d0, d0, M_\s9 vadd.u64 d1, d1, M_\s11 vadd.u64 d2, d2, M_\s13 vadd.u64 d3, d3, M_\s15 // d = ror64(d ^ a, 16); vld1.8 {M_0}, [ROR16_TABLE, :64] veor d15, d15, d0 veor d12, d12, d1 veor d13, d13, d2 veor d14, d14, d3 vtbl.8 d12, {d12}, M_0 vtbl.8 d13, {d13}, M_0 vtbl.8 d14, {d14}, M_0 vtbl.8 d15, {d15}, M_0 // c += d; vadd.u64 d10, d10, d15 vadd.u64 d11, d11, d12 vadd.u64 d8, d8, d13 vadd.u64 d9, d9, d14 // b = ror64(b ^ c, 63); veor d16, d4, d9 veor d17, d5, d10 veor d18, d6, d11 veor d19, d7, d8 vshr.u64 q2, q8, #63 vshr.u64 q3, q9, #63 vsli.u64 q2, q8, #1 vsli.u64 q3, q9, #1 // Reloading q8-q9 can be skipped on the final round. .if ! \final vld1.8 {q8-q9}, [sp, :256] .endif .endm // // void blake2b_compress_neon(struct blake2b_state *state, // const u8 *block, size_t nblocks, u32 inc); // // Only the first three fields of struct blake2b_state are used: // u64 h[8]; (inout) // u64 t[2]; (inout) // u64 f[2]; (in) // .align 5 ENTRY(blake2b_compress_neon) push {r4-r10} // Allocate a 32-byte stack buffer that is 32-byte aligned. mov ORIG_SP, sp sub ip, sp, #32 bic ip, ip, #31 mov sp, ip adr ROR24_TABLE, .Lror24_table adr ROR16_TABLE, .Lror16_table mov ip, STATE vld1.64 {q0-q1}, [ip]! // Load h[0..3] vld1.64 {q2-q3}, [ip]! // Load h[4..7] .Lnext_block: adr r10, .Lblake2b_IV vld1.64 {q14-q15}, [ip] // Load t[0..1] and f[0..1] vld1.64 {q4-q5}, [r10]! // Load IV[0..3] vmov r7, r8, d28 // Copy t[0] to (r7, r8) vld1.64 {q6-q7}, [r10] // Load IV[4..7] adds r7, r7, INC // Increment counter bcs .Lslow_inc_ctr vmov.i32 d28[0], r7 vst1.64 {d28}, [ip] // Update t[0] .Linc_ctr_done: // Load the next message block and finish initializing the state matrix // 'v'. Fortunately, there are exactly enough NEON registers to fit the // entire state matrix in q0-q7 and the entire message block in q8-15. // // However, _blake2b_round also needs some extra registers for rotates, // so we have to spill some registers. It's better to spill the message // registers than the state registers, as the message doesn't change. // Therefore we store a copy of the first 32 bytes of the message block // (q8-q9) in an aligned buffer on the stack so that they can be // reloaded when needed. (We could just reload directly from the // message buffer, but it's faster to use aligned loads.) vld1.8 {q8-q9}, [BLOCK]! veor q6, q6, q14 // v[12..13] = IV[4..5] ^ t[0..1] vld1.8 {q10-q11}, [BLOCK]! veor q7, q7, q15 // v[14..15] = IV[6..7] ^ f[0..1] vld1.8 {q12-q13}, [BLOCK]! vst1.8 {q8-q9}, [sp, :256] mov ip, STATE vld1.8 {q14-q15}, [BLOCK]! // Execute the rounds. Each round is provided the order in which it // needs to use the message words. _blake2b_round 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 _blake2b_round 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 _blake2b_round 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 _blake2b_round 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 _blake2b_round 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 _blake2b_round 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 _blake2b_round 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 _blake2b_round 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 _blake2b_round 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 _blake2b_round 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 _blake2b_round 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 _blake2b_round 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 \ final=1 // Fold the final state matrix into the hash chaining value: // // for (i = 0; i < 8; i++) // h[i] ^= v[i] ^ v[i + 8]; // vld1.64 {q8-q9}, [ip]! // Load old h[0..3] veor q0, q0, q4 // v[0..1] ^= v[8..9] veor q1, q1, q5 // v[2..3] ^= v[10..11] vld1.64 {q10-q11}, [ip] // Load old h[4..7] veor q2, q2, q6 // v[4..5] ^= v[12..13] veor q3, q3, q7 // v[6..7] ^= v[14..15] veor q0, q0, q8 // v[0..1] ^= h[0..1] veor q1, q1, q9 // v[2..3] ^= h[2..3] mov ip, STATE subs NBLOCKS, NBLOCKS, #1 // nblocks-- vst1.64 {q0-q1}, [ip]! // Store new h[0..3] veor q2, q2, q10 // v[4..5] ^= h[4..5] veor q3, q3, q11 // v[6..7] ^= h[6..7] vst1.64 {q2-q3}, [ip]! // Store new h[4..7] // Advance to the next block, if there is one. bne .Lnext_block // nblocks != 0? mov sp, ORIG_SP pop {r4-r10} mov pc, lr .Lslow_inc_ctr: // Handle the case where the counter overflowed its low 32 bits, by // carrying the overflow bit into the full 128-bit counter. vmov r9, r10, d29 adcs r8, r8, #0 adcs r9, r9, #0 adc r10, r10, #0 vmov d28, r7, r8 vmov d29, r9, r10 vst1.64 {q14}, [ip] // Update t[0] and t[1] b .Linc_ctr_done ENDPROC(blake2b_compress_neon)