This integrates the accelerated MIPS 32r2 implementation of ChaCha into both the API and library interfaces of the kernel crypto stack. The significance of this is that, in addition to becoming available as an accelerated library implementation, it can also be used by existing crypto API code such as Adiantum (for block encryption on ultra low performance cores) or IPsec using chacha20poly1305. These are use cases that have already opted into using the abstract crypto API. In order to support Adiantum, the core assembler routine has been adapted to take the round count as a function argument rather than hardcoding it to 20. Co-developed-by: René van Dorst <opensource@xxxxxxxxxx> Signed-off-by: René van Dorst <opensource@xxxxxxxxxx> Co-developed-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> --- arch/mips/Makefile | 2 +- arch/mips/crypto/Makefile | 3 + arch/mips/crypto/chacha-core.S | 424 ++++++++++++++++++++ arch/mips/crypto/chacha-glue.c | 161 ++++++++ crypto/Kconfig | 6 + 5 files changed, 595 insertions(+), 1 deletion(-) diff --git a/arch/mips/Makefile b/arch/mips/Makefile index cdc09b71febe..8584c047ea59 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -323,7 +323,7 @@ libs-$(CONFIG_MIPS_FP_SUPPORT) += arch/mips/math-emu/ # See arch/mips/Kbuild for content of core part of the kernel core-y += arch/mips/ -drivers-$(CONFIG_MIPS_CRC_SUPPORT) += arch/mips/crypto/ +drivers-y += arch/mips/crypto/ drivers-$(CONFIG_OPROFILE) += arch/mips/oprofile/ # suspend and hibernation support diff --git a/arch/mips/crypto/Makefile b/arch/mips/crypto/Makefile index e07aca572c2e..7f7ea0020cc2 100644 --- a/arch/mips/crypto/Makefile +++ b/arch/mips/crypto/Makefile @@ -4,3 +4,6 @@ # obj-$(CONFIG_CRYPTO_CRC32_MIPS) += crc32-mips.o + +obj-$(CONFIG_CRYPTO_CHACHA_MIPS) += chacha-mips.o +chacha-mips-y := chacha-core.o chacha-glue.o diff --git a/arch/mips/crypto/chacha-core.S b/arch/mips/crypto/chacha-core.S new file mode 100644 index 000000000000..42150d15fc88 --- /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@xxxxxxxxxx>. All Rights Reserved. + * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@xxxxxxxxx>. 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(.Lchacha_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(.Lchacha_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) \ +.Lchacha_mips_jmptbl_aligned_ ## x: ; \ + .set noreorder; \ + b .Lchacha_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) \ +.Lchacha_mips_jmptbl_unaligned_ ## x: ; \ + .set noreorder; \ + b .Lchacha_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 chacha_mips +.ent chacha_mips +chacha_mips: + .frame $sp, STACK_SIZE, $ra + + /* Load number of rounds */ + lw $at, 16($sp) + + addiu $sp, -STACK_SIZE + + /* Return bytes = 0. */ + beqz BYTES, .Lchacha_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 + + b .Lchacha_rounds_start + +.align 4 +.Loop_chacha_rounds: + addiu IN, CHACHA20_BLOCK_SIZE + addiu OUT, CHACHA20_BLOCK_SIZE + addiu NONCE_0, 1 + +.Lchacha_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_chacha_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_chacha_xor_rounds + + addiu BYTES, -(CHACHA20_BLOCK_SIZE) + + /* Is data src/dst unaligned? Jump */ + bnez IS_UNALIGNED, .Loop_chacha_unaligned + + /* Set number rounds here to fill delayslot. */ + lw $at, (STACK_SIZE+16)($sp) + + /* BYTES < 0, it has no full block. */ + bltz BYTES, .Lchacha_mips_no_full_block_aligned + + FOR_EACH_WORD_REV(STORE_ALIGNED) + + /* BYTES > 0? Loop again. */ + bgtz BYTES, .Loop_chacha_rounds + + /* Place this here to fill delay slot */ + addiu NONCE_0, 1 + + /* BYTES < 0? Handle last bytes */ + bltz BYTES, .Lchacha_mips_xor_bytes + +.Lchacha_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) + +.Lchacha_mips_end: + addiu $sp, STACK_SIZE + jr $ra + +.Lchacha_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(.Lchacha_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(.Lchacha_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_chacha_unaligned: + /* Set number rounds here to fill delayslot. */ + lw $at, (STACK_SIZE+16)($sp) + + /* BYTES > 0, it has no full block. */ + bltz BYTES, .Lchacha_mips_no_full_block_unaligned + + FOR_EACH_WORD_REV(STORE_UNALIGNED) + + /* BYTES > 0? Loop again. */ + bgtz BYTES, .Loop_chacha_rounds + + /* Write NONCE_0 back to right location in state */ + sw NONCE_0, 48(STATE) + + .set noreorder + /* Fall through to byte handling */ + bgez BYTES, .Lchacha_mips_xor_done +.Lchacha_mips_xor_unaligned_0_b: +.Lchacha_mips_xor_aligned_0_b: + /* Place this here to fill delay slot */ + addiu NONCE_0, 1 + .set reorder + +.Lchacha_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, .Lchacha_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, .Lchacha_mips_xor_done + /* Third byte */ + lbu T1, 2(IN) + ROTx SAVED_X, 8 + xor T1, SAVED_X + sb T1, 2(OUT) + b .Lchacha_mips_xor_done + +.Lchacha_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(.Lchacha_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(.Lchacha_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 chacha_mips +.set at diff --git a/arch/mips/crypto/chacha-glue.c b/arch/mips/crypto/chacha-glue.c new file mode 100644 index 000000000000..de01dc57751e --- /dev/null +++ b/arch/mips/crypto/chacha-glue.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * MIPS accelerated ChaCha and XChaCha stream ciphers, + * including ChaCha20 (RFC7539) + * + * Copyright (C) 2019 Linaro, Ltd. <ard.biesheuvel@xxxxxxxxxx> + */ + +#include <crypto/algapi.h> +#include <crypto/internal/chacha.h> +#include <crypto/internal/skcipher.h> +#include <linux/kernel.h> +#include <linux/module.h> + +asmlinkage void chacha_mips(const u32 *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds); + +void hchacha_block(const u32 *state, u32 *stream, int nrounds) +{ + hchacha_block_generic(state, stream, nrounds); +} +EXPORT_SYMBOL(hchacha_block); + +void chacha_init(u32 *state, const u32 *key, const u8 *iv) +{ + chacha_init_generic(state, key, iv); +} +EXPORT_SYMBOL(chacha_init); + +void chacha_crypt(u32 *state, u8 *dst, const u8 *src, unsigned int bytes, + int nrounds) +{ + chacha_mips(state, dst, src, bytes, nrounds); +} +EXPORT_SYMBOL(chacha_crypt); + +static int chacha_mips_stream_xor(struct skcipher_request *req, + const struct chacha_ctx *ctx, const u8 *iv) +{ + struct skcipher_walk walk; + u32 state[16]; + int err; + + err = skcipher_walk_virt(&walk, req, false); + + crypto_chacha_init(state, ctx, iv); + + while (walk.nbytes > 0) { + unsigned int nbytes = walk.nbytes; + + if (nbytes < walk.total) + nbytes = round_down(nbytes, walk.stride); + + chacha_mips(state, walk.dst.virt.addr, walk.src.virt.addr, + nbytes, ctx->nrounds); + err = skcipher_walk_done(&walk, walk.nbytes - nbytes); + } + + return err; +} + +static int __chacha_mips(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); + + return chacha_mips_stream_xor(req, ctx, req->iv); +} + +static int xchacha_mips(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); + struct chacha_ctx subctx; + u32 state[16]; + u8 real_iv[16]; + + crypto_chacha_init(state, ctx, req->iv); + + hchacha_block_generic(state, subctx.key, ctx->nrounds); + subctx.nrounds = ctx->nrounds; + + memcpy(&real_iv[0], req->iv + 24, 8); + memcpy(&real_iv[8], req->iv + 16, 8); + return chacha_mips_stream_xor(req, &subctx, real_iv); +} + +static struct skcipher_alg algs[] = { + { + .base.cra_name = "chacha20", + .base.cra_driver_name = "chacha20-mips", + .base.cra_priority = 200, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = CHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .walksize = 4 * CHACHA_BLOCK_SIZE, + .setkey = crypto_chacha20_setkey, + .encrypt = __chacha_mips, + .decrypt = __chacha_mips, + }, { + .base.cra_name = "xchacha20", + .base.cra_driver_name = "xchacha20-mips", + .base.cra_priority = 200, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = XCHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .walksize = 4 * CHACHA_BLOCK_SIZE, + .setkey = crypto_chacha20_setkey, + .encrypt = xchacha_mips, + .decrypt = xchacha_mips, + }, { + .base.cra_name = "xchacha12", + .base.cra_driver_name = "xchacha12-mips", + .base.cra_priority = 200, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = XCHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .walksize = 4 * CHACHA_BLOCK_SIZE, + .setkey = crypto_chacha12_setkey, + .encrypt = xchacha_mips, + .decrypt = xchacha_mips, + } +}; + +static int __init chacha_simd_mod_init(void) +{ + return crypto_register_skciphers(algs, ARRAY_SIZE(algs)); +} + +static void __exit chacha_simd_mod_fini(void) +{ + crypto_unregister_skciphers(algs, ARRAY_SIZE(algs)); +} + +module_init(chacha_simd_mod_init); +module_exit(chacha_simd_mod_fini); + +MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (MIPS accelerated)"); +MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("chacha20"); +MODULE_ALIAS_CRYPTO("chacha20-mips"); +MODULE_ALIAS_CRYPTO("xchacha20"); +MODULE_ALIAS_CRYPTO("xchacha20-mips"); +MODULE_ALIAS_CRYPTO("xchacha12"); +MODULE_ALIAS_CRYPTO("xchacha12-mips"); diff --git a/crypto/Kconfig b/crypto/Kconfig index f90b53a526ba..43e94ac5d117 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1441,6 +1441,12 @@ config CRYPTO_CHACHA20_X86_64 SSSE3, AVX2, and AVX-512VL optimized implementations of the ChaCha20, XChaCha20, and XChaCha12 stream ciphers. +config CRYPTO_CHACHA_MIPS + tristate "ChaCha stream cipher algorithms (MIPS 32r2 optimized)" + depends on CPU_MIPS32_R2 + select CRYPTO_CHACHA20 + select CRYPTO_ARCH_HAVE_LIB_CHACHA + config CRYPTO_SEED tristate "SEED cipher algorithm" select CRYPTO_ALGAPI -- 2.20.1