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Diffstat (limited to 'arch/arm/crypto/chacha-scalar-core.S')
| -rw-r--r-- | arch/arm/crypto/chacha-scalar-core.S | 443 |
1 files changed, 0 insertions, 443 deletions
diff --git a/arch/arm/crypto/chacha-scalar-core.S b/arch/arm/crypto/chacha-scalar-core.S deleted file mode 100644 index 083fe1ab96d0..000000000000 --- a/arch/arm/crypto/chacha-scalar-core.S +++ /dev/null @@ -1,443 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Copyright (C) 2018 Google, Inc. - */ - -#include <linux/linkage.h> -#include <asm/assembler.h> - -/* - * Design notes: - * - * 16 registers would be needed to hold the state matrix, but only 14 are - * available because 'sp' and 'pc' cannot be used. So we spill the elements - * (x8, x9) to the stack and swap them out with (x10, x11). This adds one - * 'ldrd' and one 'strd' instruction per round. - * - * All rotates are performed using the implicit rotate operand accepted by the - * 'add' and 'eor' instructions. This is faster than using explicit rotate - * instructions. To make this work, we allow the values in the second and last - * rows of the ChaCha state matrix (rows 'b' and 'd') to temporarily have the - * wrong rotation amount. The rotation amount is then fixed up just in time - * when the values are used. 'brot' is the number of bits the values in row 'b' - * need to be rotated right to arrive at the correct values, and 'drot' - * similarly for row 'd'. (brot, drot) start out as (0, 0) but we make it such - * that they end up as (25, 24) after every round. - */ - - // ChaCha state registers - X0 .req r0 - X1 .req r1 - X2 .req r2 - X3 .req r3 - X4 .req r4 - X5 .req r5 - X6 .req r6 - X7 .req r7 - X8_X10 .req r8 // shared by x8 and x10 - X9_X11 .req r9 // shared by x9 and x11 - X12 .req r10 - X13 .req r11 - X14 .req r12 - X15 .req r14 - -.macro _le32_bswap_4x a, b, c, d, tmp -#ifdef __ARMEB__ - rev_l \a, \tmp - rev_l \b, \tmp - rev_l \c, \tmp - rev_l \d, \tmp -#endif -.endm - -.macro __ldrd a, b, src, offset -#if __LINUX_ARM_ARCH__ >= 6 - ldrd \a, \b, [\src, #\offset] -#else - ldr \a, [\src, #\offset] - ldr \b, [\src, #\offset + 4] -#endif -.endm - -.macro __strd a, b, dst, offset -#if __LINUX_ARM_ARCH__ >= 6 - strd \a, \b, [\dst, #\offset] -#else - str \a, [\dst, #\offset] - str \b, [\dst, #\offset + 4] -#endif -.endm - -.macro _halfround a1, b1, c1, d1, a2, b2, c2, d2 - - // a += b; d ^= a; d = rol(d, 16); - add \a1, \a1, \b1, ror #brot - add \a2, \a2, \b2, ror #brot - eor \d1, \a1, \d1, ror #drot - eor \d2, \a2, \d2, ror #drot - // drot == 32 - 16 == 16 - - // c += d; b ^= c; b = rol(b, 12); - add \c1, \c1, \d1, ror #16 - add \c2, \c2, \d2, ror #16 - eor \b1, \c1, \b1, ror #brot - eor \b2, \c2, \b2, ror #brot - // brot == 32 - 12 == 20 - - // a += b; d ^= a; d = rol(d, 8); - add \a1, \a1, \b1, ror #20 - add \a2, \a2, \b2, ror #20 - eor \d1, \a1, \d1, ror #16 - eor \d2, \a2, \d2, ror #16 - // drot == 32 - 8 == 24 - - // c += d; b ^= c; b = rol(b, 7); - add \c1, \c1, \d1, ror #24 - add \c2, \c2, \d2, ror #24 - eor \b1, \c1, \b1, ror #20 - eor \b2, \c2, \b2, ror #20 - // brot == 32 - 7 == 25 -.endm - -.macro _doubleround - - // column round - - // quarterrounds: (x0, x4, x8, x12) and (x1, x5, x9, x13) - _halfround X0, X4, X8_X10, X12, X1, X5, X9_X11, X13 - - // save (x8, x9); restore (x10, x11) - __strd X8_X10, X9_X11, sp, 0 - __ldrd X8_X10, X9_X11, sp, 8 - - // quarterrounds: (x2, x6, x10, x14) and (x3, x7, x11, x15) - _halfround X2, X6, X8_X10, X14, X3, X7, X9_X11, X15 - - .set brot, 25 - .set drot, 24 - - // diagonal round - - // quarterrounds: (x0, x5, x10, x15) and (x1, x6, x11, x12) - _halfround X0, X5, X8_X10, X15, X1, X6, X9_X11, X12 - - // save (x10, x11); restore (x8, x9) - __strd X8_X10, X9_X11, sp, 8 - __ldrd X8_X10, X9_X11, sp, 0 - - // quarterrounds: (x2, x7, x8, x13) and (x3, x4, x9, x14) - _halfround X2, X7, X8_X10, X13, X3, X4, X9_X11, X14 -.endm - -.macro _chacha_permute nrounds - .set brot, 0 - .set drot, 0 - .rept \nrounds / 2 - _doubleround - .endr -.endm - -.macro _chacha nrounds - -.Lnext_block\@: - // Stack: unused0-unused1 x10-x11 x0-x15 OUT IN LEN - // Registers contain x0-x9,x12-x15. - - // Do the core ChaCha permutation to update x0-x15. - _chacha_permute \nrounds - - add sp, #8 - // Stack: x10-x11 orig_x0-orig_x15 OUT IN LEN - // Registers contain x0-x9,x12-x15. - // x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'. - - // Free up some registers (r8-r12,r14) by pushing (x8-x9,x12-x15). - push {X8_X10, X9_X11, X12, X13, X14, X15} - - // Load (OUT, IN, LEN). - ldr r14, [sp, #96] - ldr r12, [sp, #100] - ldr r11, [sp, #104] - - orr r10, r14, r12 - - // Use slow path if fewer than 64 bytes remain. - cmp r11, #64 - blt .Lxor_slowpath\@ - - // Use slow path if IN and/or OUT isn't 4-byte aligned. Needed even on - // ARMv6+, since ldmia and stmia (used below) still require alignment. - tst r10, #3 - bne .Lxor_slowpath\@ - - // Fast path: XOR 64 bytes of aligned data. - - // Stack: x8-x9 x12-x15 x10-x11 orig_x0-orig_x15 OUT IN LEN - // Registers: r0-r7 are x0-x7; r8-r11 are free; r12 is IN; r14 is OUT. - // x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'. - - // x0-x3 - __ldrd r8, r9, sp, 32 - __ldrd r10, r11, sp, 40 - add X0, X0, r8 - add X1, X1, r9 - add X2, X2, r10 - add X3, X3, r11 - _le32_bswap_4x X0, X1, X2, X3, r8 - ldmia r12!, {r8-r11} - eor X0, X0, r8 - eor X1, X1, r9 - eor X2, X2, r10 - eor X3, X3, r11 - stmia r14!, {X0-X3} - - // x4-x7 - __ldrd r8, r9, sp, 48 - __ldrd r10, r11, sp, 56 - add X4, r8, X4, ror #brot - add X5, r9, X5, ror #brot - ldmia r12!, {X0-X3} - add X6, r10, X6, ror #brot - add X7, r11, X7, ror #brot - _le32_bswap_4x X4, X5, X6, X7, r8 - eor X4, X4, X0 - eor X5, X5, X1 - eor X6, X6, X2 - eor X7, X7, X3 - stmia r14!, {X4-X7} - - // x8-x15 - pop {r0-r7} // (x8-x9,x12-x15,x10-x11) - __ldrd r8, r9, sp, 32 - __ldrd r10, r11, sp, 40 - add r0, r0, r8 // x8 - add r1, r1, r9 // x9 - add r6, r6, r10 // x10 - add r7, r7, r11 // x11 - _le32_bswap_4x r0, r1, r6, r7, r8 - ldmia r12!, {r8-r11} - eor r0, r0, r8 // x8 - eor r1, r1, r9 // x9 - eor r6, r6, r10 // x10 - eor r7, r7, r11 // x11 - stmia r14!, {r0,r1,r6,r7} - ldmia r12!, {r0,r1,r6,r7} - __ldrd r8, r9, sp, 48 - __ldrd r10, r11, sp, 56 - add r2, r8, r2, ror #drot // x12 - add r3, r9, r3, ror #drot // x13 - add r4, r10, r4, ror #drot // x14 - add r5, r11, r5, ror #drot // x15 - _le32_bswap_4x r2, r3, r4, r5, r9 - ldr r9, [sp, #72] // load LEN - eor r2, r2, r0 // x12 - eor r3, r3, r1 // x13 - eor r4, r4, r6 // x14 - eor r5, r5, r7 // x15 - subs r9, #64 // decrement and check LEN - stmia r14!, {r2-r5} - - beq .Ldone\@ - -.Lprepare_for_next_block\@: - - // Stack: x0-x15 OUT IN LEN - - // Increment block counter (x12) - add r8, #1 - - // Store updated (OUT, IN, LEN) - str r14, [sp, #64] - str r12, [sp, #68] - str r9, [sp, #72] - - mov r14, sp - - // Store updated block counter (x12) - str r8, [sp, #48] - - sub sp, #16 - - // Reload state and do next block - ldmia r14!, {r0-r11} // load x0-x11 - __strd r10, r11, sp, 8 // store x10-x11 before state - ldmia r14, {r10-r12,r14} // load x12-x15 - b .Lnext_block\@ - -.Lxor_slowpath\@: - // Slow path: < 64 bytes remaining, or unaligned input or output buffer. - // We handle it by storing the 64 bytes of keystream to the stack, then - // XOR-ing the needed portion with the data. - - // Allocate keystream buffer - sub sp, #64 - mov r14, sp - - // Stack: ks0-ks15 x8-x9 x12-x15 x10-x11 orig_x0-orig_x15 OUT IN LEN - // Registers: r0-r7 are x0-x7; r8-r11 are free; r12 is IN; r14 is &ks0. - // x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'. - - // Save keystream for x0-x3 - __ldrd r8, r9, sp, 96 - __ldrd r10, r11, sp, 104 - add X0, X0, r8 - add X1, X1, r9 - add X2, X2, r10 - add X3, X3, r11 - _le32_bswap_4x X0, X1, X2, X3, r8 - stmia r14!, {X0-X3} - - // Save keystream for x4-x7 - __ldrd r8, r9, sp, 112 - __ldrd r10, r11, sp, 120 - add X4, r8, X4, ror #brot - add X5, r9, X5, ror #brot - add X6, r10, X6, ror #brot - add X7, r11, X7, ror #brot - _le32_bswap_4x X4, X5, X6, X7, r8 - add r8, sp, #64 - stmia r14!, {X4-X7} - - // Save keystream for x8-x15 - ldm r8, {r0-r7} // (x8-x9,x12-x15,x10-x11) - __ldrd r8, r9, sp, 128 - __ldrd r10, r11, sp, 136 - add r0, r0, r8 // x8 - add r1, r1, r9 // x9 - add r6, r6, r10 // x10 - add r7, r7, r11 // x11 - _le32_bswap_4x r0, r1, r6, r7, r8 - stmia r14!, {r0,r1,r6,r7} - __ldrd r8, r9, sp, 144 - __ldrd r10, r11, sp, 152 - add r2, r8, r2, ror #drot // x12 - add r3, r9, r3, ror #drot // x13 - add r4, r10, r4, ror #drot // x14 - add r5, r11, r5, ror #drot // x15 - _le32_bswap_4x r2, r3, r4, r5, r9 - stmia r14, {r2-r5} - - // Stack: ks0-ks15 unused0-unused7 x0-x15 OUT IN LEN - // Registers: r8 is block counter, r12 is IN. - - ldr r9, [sp, #168] // LEN - ldr r14, [sp, #160] // OUT - cmp r9, #64 - mov r0, sp - movle r1, r9 - movgt r1, #64 - // r1 is number of bytes to XOR, in range [1, 64] - -.if __LINUX_ARM_ARCH__ < 6 - orr r2, r12, r14 - tst r2, #3 // IN or OUT misaligned? - bne .Lxor_next_byte\@ -.endif - - // XOR a word at a time -.rept 16 - subs r1, #4 - blt .Lxor_words_done\@ - ldr r2, [r12], #4 - ldr r3, [r0], #4 - eor r2, r2, r3 - str r2, [r14], #4 -.endr - b .Lxor_slowpath_done\@ -.Lxor_words_done\@: - ands r1, r1, #3 - beq .Lxor_slowpath_done\@ - - // XOR a byte at a time -.Lxor_next_byte\@: - ldrb r2, [r12], #1 - ldrb r3, [r0], #1 - eor r2, r2, r3 - strb r2, [r14], #1 - subs r1, #1 - bne .Lxor_next_byte\@ - -.Lxor_slowpath_done\@: - subs r9, #64 - add sp, #96 - bgt .Lprepare_for_next_block\@ - -.Ldone\@: -.endm // _chacha - -/* - * void chacha_doarm(u8 *dst, const u8 *src, unsigned int bytes, - * const u32 *state, int nrounds); - */ -ENTRY(chacha_doarm) - cmp r2, #0 // len == 0? - reteq lr - - ldr ip, [sp] - cmp ip, #12 - - push {r0-r2,r4-r11,lr} - - // Push state x0-x15 onto stack. - // Also store an extra copy of x10-x11 just before the state. - - add X12, r3, #48 - ldm X12, {X12,X13,X14,X15} - push {X12,X13,X14,X15} - sub sp, sp, #64 - - __ldrd X8_X10, X9_X11, r3, 40 - __strd X8_X10, X9_X11, sp, 8 - __strd X8_X10, X9_X11, sp, 56 - ldm r3, {X0-X9_X11} - __strd X0, X1, sp, 16 - __strd X2, X3, sp, 24 - __strd X4, X5, sp, 32 - __strd X6, X7, sp, 40 - __strd X8_X10, X9_X11, sp, 48 - - beq 1f - _chacha 20 - -0: add sp, #76 - pop {r4-r11, pc} - -1: _chacha 12 - b 0b -ENDPROC(chacha_doarm) - -/* - * void hchacha_block_arm(const u32 state[16], u32 out[8], int nrounds); - */ -ENTRY(hchacha_block_arm) - push {r1,r4-r11,lr} - - cmp r2, #12 // ChaCha12 ? - - mov r14, r0 - ldmia r14!, {r0-r11} // load x0-x11 - push {r10-r11} // store x10-x11 to stack - ldm r14, {r10-r12,r14} // load x12-x15 - sub sp, #8 - - beq 1f - _chacha_permute 20 - - // Skip over (unused0-unused1, x10-x11) -0: add sp, #16 - - // Fix up rotations of x12-x15 - ror X12, X12, #drot - ror X13, X13, #drot - pop {r4} // load 'out' - ror X14, X14, #drot - ror X15, X15, #drot - - // Store (x0-x3,x12-x15) to 'out' - stm r4, {X0,X1,X2,X3,X12,X13,X14,X15} - - pop {r4-r11,pc} - -1: _chacha_permute 12 - b 0b -ENDPROC(hchacha_block_arm) |