diff options
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/crypto/chacha-core.S | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/arch/mips/crypto/chacha-core.S b/arch/mips/crypto/chacha-core.S new file mode 100644 index 000000000000..a81e02db95e7 --- /dev/null +++ b/arch/mips/crypto/chacha-core.S @@ -0,0 +1,424 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ +/* + * Copyright (C) 2016-2018 René van Dorst <opensource@vdorst.com>. All Rights Reserved. + * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. + */ + +#define MASK_U32 0x3c +#define CHACHA20_BLOCK_SIZE 64 +#define STACK_SIZE 32 + +#define X0 $t0 +#define X1 $t1 +#define X2 $t2 +#define X3 $t3 +#define X4 $t4 +#define X5 $t5 +#define X6 $t6 +#define X7 $t7 +#define X8 $t8 +#define X9 $t9 +#define X10 $v1 +#define X11 $s6 +#define X12 $s5 +#define X13 $s4 +#define X14 $s3 +#define X15 $s2 +/* Use regs which are overwritten on exit for Tx so we don't leak clear data. */ +#define T0 $s1 +#define T1 $s0 +#define T(n) T ## n +#define X(n) X ## n + +/* Input arguments */ +#define STATE $a0 +#define OUT $a1 +#define IN $a2 +#define BYTES $a3 + +/* Output argument */ +/* NONCE[0] is kept in a register and not in memory. + * We don't want to touch original value in memory. + * Must be incremented every loop iteration. + */ +#define NONCE_0 $v0 + +/* SAVED_X and SAVED_CA are set in the jump table. + * Use regs which are overwritten on exit else we don't leak clear data. + * They are used to handling the last bytes which are not multiple of 4. + */ +#define SAVED_X X15 +#define SAVED_CA $s7 + +#define IS_UNALIGNED $s7 + +#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +#define MSB 0 +#define LSB 3 +#define ROTx rotl +#define ROTR(n) rotr n, 24 +#define CPU_TO_LE32(n) \ + wsbh n; \ + rotr n, 16; +#else +#define MSB 3 +#define LSB 0 +#define ROTx rotr +#define CPU_TO_LE32(n) +#define ROTR(n) +#endif + +#define FOR_EACH_WORD(x) \ + x( 0); \ + x( 1); \ + x( 2); \ + x( 3); \ + x( 4); \ + x( 5); \ + x( 6); \ + x( 7); \ + x( 8); \ + x( 9); \ + x(10); \ + x(11); \ + x(12); \ + x(13); \ + x(14); \ + x(15); + +#define FOR_EACH_WORD_REV(x) \ + x(15); \ + x(14); \ + x(13); \ + x(12); \ + x(11); \ + x(10); \ + x( 9); \ + x( 8); \ + x( 7); \ + x( 6); \ + x( 5); \ + x( 4); \ + x( 3); \ + x( 2); \ + x( 1); \ + x( 0); + +#define PLUS_ONE_0 1 +#define PLUS_ONE_1 2 +#define PLUS_ONE_2 3 +#define PLUS_ONE_3 4 +#define PLUS_ONE_4 5 +#define PLUS_ONE_5 6 +#define PLUS_ONE_6 7 +#define PLUS_ONE_7 8 +#define PLUS_ONE_8 9 +#define PLUS_ONE_9 10 +#define PLUS_ONE_10 11 +#define PLUS_ONE_11 12 +#define PLUS_ONE_12 13 +#define PLUS_ONE_13 14 +#define PLUS_ONE_14 15 +#define PLUS_ONE_15 16 +#define PLUS_ONE(x) PLUS_ONE_ ## x +#define _CONCAT3(a,b,c) a ## b ## c +#define CONCAT3(a,b,c) _CONCAT3(a,b,c) + +#define STORE_UNALIGNED(x) \ +CONCAT3(.Lchacha20_mips_xor_unaligned_, PLUS_ONE(x), _b: ;) \ + .if (x != 12); \ + lw T0, (x*4)(STATE); \ + .endif; \ + lwl T1, (x*4)+MSB ## (IN); \ + lwr T1, (x*4)+LSB ## (IN); \ + .if (x == 12); \ + addu X ## x, NONCE_0; \ + .else; \ + addu X ## x, T0; \ + .endif; \ + CPU_TO_LE32(X ## x); \ + xor X ## x, T1; \ + swl X ## x, (x*4)+MSB ## (OUT); \ + swr X ## x, (x*4)+LSB ## (OUT); + +#define STORE_ALIGNED(x) \ +CONCAT3(.Lchacha20_mips_xor_aligned_, PLUS_ONE(x), _b: ;) \ + .if (x != 12); \ + lw T0, (x*4)(STATE); \ + .endif; \ + lw T1, (x*4) ## (IN); \ + .if (x == 12); \ + addu X ## x, NONCE_0; \ + .else; \ + addu X ## x, T0; \ + .endif; \ + CPU_TO_LE32(X ## x); \ + xor X ## x, T1; \ + sw X ## x, (x*4) ## (OUT); + +/* Jump table macro. + * Used for setup and handling the last bytes, which are not multiple of 4. + * X15 is free to store Xn + * Every jumptable entry must be equal in size. + */ +#define JMPTBL_ALIGNED(x) \ +.Lchacha20_mips_jmptbl_aligned_ ## x: ; \ + .set noreorder; \ + b .Lchacha20_mips_xor_aligned_ ## x ## _b; \ + .if (x == 12); \ + addu SAVED_X, X ## x, NONCE_0; \ + .else; \ + addu SAVED_X, X ## x, SAVED_CA; \ + .endif; \ + .set reorder + +#define JMPTBL_UNALIGNED(x) \ +.Lchacha20_mips_jmptbl_unaligned_ ## x: ; \ + .set noreorder; \ + b .Lchacha20_mips_xor_unaligned_ ## x ## _b; \ + .if (x == 12); \ + addu SAVED_X, X ## x, NONCE_0; \ + .else; \ + addu SAVED_X, X ## x, SAVED_CA; \ + .endif; \ + .set reorder + +#define AXR(A, B, C, D, K, L, M, N, V, W, Y, Z, S) \ + addu X(A), X(K); \ + addu X(B), X(L); \ + addu X(C), X(M); \ + addu X(D), X(N); \ + xor X(V), X(A); \ + xor X(W), X(B); \ + xor X(Y), X(C); \ + xor X(Z), X(D); \ + rotl X(V), S; \ + rotl X(W), S; \ + rotl X(Y), S; \ + rotl X(Z), S; + +.text +.set reorder +.set noat +.globl chacha20_mips +.ent chacha20_mips +chacha20_mips: + .frame $sp, STACK_SIZE, $ra + + addiu $sp, -STACK_SIZE + + /* Return bytes = 0. */ + beqz BYTES, .Lchacha20_mips_end + + lw NONCE_0, 48(STATE) + + /* Save s0-s7 */ + sw $s0, 0($sp) + sw $s1, 4($sp) + sw $s2, 8($sp) + sw $s3, 12($sp) + sw $s4, 16($sp) + sw $s5, 20($sp) + sw $s6, 24($sp) + sw $s7, 28($sp) + + /* Test IN or OUT is unaligned. + * IS_UNALIGNED = ( IN | OUT ) & 0x00000003 + */ + or IS_UNALIGNED, IN, OUT + andi IS_UNALIGNED, 0x3 + + /* Set number of rounds */ + li $at, 20 + + b .Lchacha20_rounds_start + +.align 4 +.Loop_chacha20_rounds: + addiu IN, CHACHA20_BLOCK_SIZE + addiu OUT, CHACHA20_BLOCK_SIZE + addiu NONCE_0, 1 + +.Lchacha20_rounds_start: + lw X0, 0(STATE) + lw X1, 4(STATE) + lw X2, 8(STATE) + lw X3, 12(STATE) + + lw X4, 16(STATE) + lw X5, 20(STATE) + lw X6, 24(STATE) + lw X7, 28(STATE) + lw X8, 32(STATE) + lw X9, 36(STATE) + lw X10, 40(STATE) + lw X11, 44(STATE) + + move X12, NONCE_0 + lw X13, 52(STATE) + lw X14, 56(STATE) + lw X15, 60(STATE) + +.Loop_chacha20_xor_rounds: + addiu $at, -2 + AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 16); + AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 12); + AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 8); + AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 7); + AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 16); + AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 12); + AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 8); + AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 7); + bnez $at, .Loop_chacha20_xor_rounds + + addiu BYTES, -(CHACHA20_BLOCK_SIZE) + + /* Is data src/dst unaligned? Jump */ + bnez IS_UNALIGNED, .Loop_chacha20_unaligned + + /* Set number rounds here to fill delayslot. */ + li $at, 20 + + /* BYTES < 0, it has no full block. */ + bltz BYTES, .Lchacha20_mips_no_full_block_aligned + + FOR_EACH_WORD_REV(STORE_ALIGNED) + + /* BYTES > 0? Loop again. */ + bgtz BYTES, .Loop_chacha20_rounds + + /* Place this here to fill delay slot */ + addiu NONCE_0, 1 + + /* BYTES < 0? Handle last bytes */ + bltz BYTES, .Lchacha20_mips_xor_bytes + +.Lchacha20_mips_xor_done: + /* Restore used registers */ + lw $s0, 0($sp) + lw $s1, 4($sp) + lw $s2, 8($sp) + lw $s3, 12($sp) + lw $s4, 16($sp) + lw $s5, 20($sp) + lw $s6, 24($sp) + lw $s7, 28($sp) + + /* Write NONCE_0 back to right location in state */ + sw NONCE_0, 48(STATE) + +.Lchacha20_mips_end: + addiu $sp, STACK_SIZE + jr $ra + +.Lchacha20_mips_no_full_block_aligned: + /* Restore the offset on BYTES */ + addiu BYTES, CHACHA20_BLOCK_SIZE + + /* Get number of full WORDS */ + andi $at, BYTES, MASK_U32 + + /* Load upper half of jump table addr */ + lui T0, %hi(.Lchacha20_mips_jmptbl_aligned_0) + + /* Calculate lower half jump table offset */ + ins T0, $at, 1, 6 + + /* Add offset to STATE */ + addu T1, STATE, $at + + /* Add lower half jump table addr */ + addiu T0, %lo(.Lchacha20_mips_jmptbl_aligned_0) + + /* Read value from STATE */ + lw SAVED_CA, 0(T1) + + /* Store remaining bytecounter as negative value */ + subu BYTES, $at, BYTES + + jr T0 + + /* Jump table */ + FOR_EACH_WORD(JMPTBL_ALIGNED) + + +.Loop_chacha20_unaligned: + /* Set number rounds here to fill delayslot. */ + li $at, 20 + + /* BYTES > 0, it has no full block. */ + bltz BYTES, .Lchacha20_mips_no_full_block_unaligned + + FOR_EACH_WORD_REV(STORE_UNALIGNED) + + /* BYTES > 0? Loop again. */ + bgtz BYTES, .Loop_chacha20_rounds + + /* Write NONCE_0 back to right location in state */ + sw NONCE_0, 48(STATE) + + .set noreorder + /* Fall through to byte handling */ + bgez BYTES, .Lchacha20_mips_xor_done +.Lchacha20_mips_xor_unaligned_0_b: +.Lchacha20_mips_xor_aligned_0_b: + /* Place this here to fill delay slot */ + addiu NONCE_0, 1 + .set reorder + +.Lchacha20_mips_xor_bytes: + addu IN, $at + addu OUT, $at + /* First byte */ + lbu T1, 0(IN) + addiu $at, BYTES, 1 + CPU_TO_LE32(SAVED_X) + ROTR(SAVED_X) + xor T1, SAVED_X + sb T1, 0(OUT) + beqz $at, .Lchacha20_mips_xor_done + /* Second byte */ + lbu T1, 1(IN) + addiu $at, BYTES, 2 + ROTx SAVED_X, 8 + xor T1, SAVED_X + sb T1, 1(OUT) + beqz $at, .Lchacha20_mips_xor_done + /* Third byte */ + lbu T1, 2(IN) + ROTx SAVED_X, 8 + xor T1, SAVED_X + sb T1, 2(OUT) + b .Lchacha20_mips_xor_done + +.Lchacha20_mips_no_full_block_unaligned: + /* Restore the offset on BYTES */ + addiu BYTES, CHACHA20_BLOCK_SIZE + + /* Get number of full WORDS */ + andi $at, BYTES, MASK_U32 + + /* Load upper half of jump table addr */ + lui T0, %hi(.Lchacha20_mips_jmptbl_unaligned_0) + + /* Calculate lower half jump table offset */ + ins T0, $at, 1, 6 + + /* Add offset to STATE */ + addu T1, STATE, $at + + /* Add lower half jump table addr */ + addiu T0, %lo(.Lchacha20_mips_jmptbl_unaligned_0) + + /* Read value from STATE */ + lw SAVED_CA, 0(T1) + + /* Store remaining bytecounter as negative value */ + subu BYTES, $at, BYTES + + jr T0 + + /* Jump table */ + FOR_EACH_WORD(JMPTBL_UNALIGNED) +.end chacha20_mips +.set at |