crypto: ghash - Add PCLMULQDQ accelerated implementation
authorHuang Ying <ying.huang@intel.com>
Mon, 19 Oct 2009 02:53:06 +0000 (11:53 +0900)
committerHerbert Xu <herbert@gondor.apana.org.au>
Mon, 19 Oct 2009 02:53:06 +0000 (11:53 +0900)
PCLMULQDQ is used to accelerate the most time-consuming part of GHASH,
carry-less multiplication. More information about PCLMULQDQ can be
found at:

http://software.intel.com/en-us/articles/carry-less-multiplication-and-its-usage-for-computing-the-gcm-mode/

Because PCLMULQDQ changes XMM state, its usage must be enclosed with
kernel_fpu_begin/end, which can be used only in process context, the
acceleration is implemented as crypto_ahash. That is, request in soft
IRQ context will be defered to the cryptd kernel thread.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
arch/x86/crypto/Makefile
arch/x86/crypto/ghash-clmulni-intel_asm.S [new file with mode: 0644]
arch/x86/crypto/ghash-clmulni-intel_glue.c [new file with mode: 0644]
arch/x86/include/asm/cpufeature.h
crypto/Kconfig
crypto/cryptd.c
include/crypto/cryptd.h

index cfb0010..1a58ad8 100644 (file)
@@ -12,6 +12,7 @@ obj-$(CONFIG_CRYPTO_AES_X86_64) += aes-x86_64.o
 obj-$(CONFIG_CRYPTO_TWOFISH_X86_64) += twofish-x86_64.o
 obj-$(CONFIG_CRYPTO_SALSA20_X86_64) += salsa20-x86_64.o
 obj-$(CONFIG_CRYPTO_AES_NI_INTEL) += aesni-intel.o
+obj-$(CONFIG_CRYPTO_GHASH_CLMUL_NI_INTEL) += ghash-clmulni-intel.o
 
 obj-$(CONFIG_CRYPTO_CRC32C_INTEL) += crc32c-intel.o
 
@@ -24,3 +25,5 @@ twofish-x86_64-y := twofish-x86_64-asm_64.o twofish_glue.o
 salsa20-x86_64-y := salsa20-x86_64-asm_64.o salsa20_glue.o
 
 aesni-intel-y := aesni-intel_asm.o aesni-intel_glue.o
+
+ghash-clmulni-intel-y := ghash-clmulni-intel_asm.o ghash-clmulni-intel_glue.o
diff --git a/arch/x86/crypto/ghash-clmulni-intel_asm.S b/arch/x86/crypto/ghash-clmulni-intel_asm.S
new file mode 100644 (file)
index 0000000..b9e787a
--- /dev/null
@@ -0,0 +1,157 @@
+/*
+ * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
+ * instructions. This file contains accelerated part of ghash
+ * implementation. More information about PCLMULQDQ can be found at:
+ *
+ * http://software.intel.com/en-us/articles/carry-less-multiplication-and-its-usage-for-computing-the-gcm-mode/
+ *
+ * Copyright (c) 2009 Intel Corp.
+ *   Author: Huang Ying <ying.huang@intel.com>
+ *          Vinodh Gopal
+ *          Erdinc Ozturk
+ *          Deniz Karakoyunlu
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/linkage.h>
+
+.align 16
+.Lbswap_mask:
+       .octa 0x000102030405060708090a0b0c0d0e0f
+.Lpoly:
+       .octa 0xc2000000000000000000000000000001
+.Ltwo_one:
+       .octa 0x00000001000000000000000000000001
+
+#define DATA   %xmm0
+#define SHASH  %xmm1
+#define T1     %xmm2
+#define T2     %xmm3
+#define T3     %xmm4
+#define BSWAP  %xmm5
+#define IN1    %xmm6
+
+.text
+
+/*
+ * __clmul_gf128mul_ble:       internal ABI
+ * input:
+ *     DATA:                   operand1
+ *     SHASH:                  operand2, hash_key << 1 mod poly
+ * output:
+ *     DATA:                   operand1 * operand2 mod poly
+ * changed:
+ *     T1
+ *     T2
+ *     T3
+ */
+__clmul_gf128mul_ble:
+       movaps DATA, T1
+       pshufd $0b01001110, DATA, T2
+       pshufd $0b01001110, SHASH, T3
+       pxor DATA, T2
+       pxor SHASH, T3
+
+       # pclmulqdq $0x00, SHASH, DATA  # DATA = a0 * b0
+       .byte 0x66, 0x0f, 0x3a, 0x44, 0xc1, 0x00
+       # pclmulqdq $0x11, SHASH, T1    # T1 = a1 * b1
+       .byte 0x66, 0x0f, 0x3a, 0x44, 0xd1, 0x11
+       # pclmulqdq $0x00, T3, T2       # T2 = (a1 + a0) * (b1 + b0)
+       .byte 0x66, 0x0f, 0x3a, 0x44, 0xdc, 0x00
+       pxor DATA, T2
+       pxor T1, T2                     # T2 = a0 * b1 + a1 * b0
+
+       movaps T2, T3
+       pslldq $8, T3
+       psrldq $8, T2
+       pxor T3, DATA
+       pxor T2, T1                     # <T1:DATA> is result of
+                                       # carry-less multiplication
+
+       # first phase of the reduction
+       movaps DATA, T3
+       psllq $1, T3
+       pxor DATA, T3
+       psllq $5, T3
+       pxor DATA, T3
+       psllq $57, T3
+       movaps T3, T2
+       pslldq $8, T2
+       psrldq $8, T3
+       pxor T2, DATA
+       pxor T3, T1
+
+       # second phase of the reduction
+       movaps DATA, T2
+       psrlq $5, T2
+       pxor DATA, T2
+       psrlq $1, T2
+       pxor DATA, T2
+       psrlq $1, T2
+       pxor T2, T1
+       pxor T1, DATA
+       ret
+
+/* void clmul_ghash_mul(char *dst, const be128 *shash) */
+ENTRY(clmul_ghash_mul)
+       movups (%rdi), DATA
+       movups (%rsi), SHASH
+       movaps .Lbswap_mask, BSWAP
+       pshufb BSWAP, DATA
+       call __clmul_gf128mul_ble
+       pshufb BSWAP, DATA
+       movups DATA, (%rdi)
+       ret
+
+/*
+ * void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
+ *                        const be128 *shash);
+ */
+ENTRY(clmul_ghash_update)
+       cmp $16, %rdx
+       jb .Lupdate_just_ret    # check length
+       movaps .Lbswap_mask, BSWAP
+       movups (%rdi), DATA
+       movups (%rcx), SHASH
+       pshufb BSWAP, DATA
+.align 4
+.Lupdate_loop:
+       movups (%rsi), IN1
+       pshufb BSWAP, IN1
+       pxor IN1, DATA
+       call __clmul_gf128mul_ble
+       sub $16, %rdx
+       add $16, %rsi
+       cmp $16, %rdx
+       jge .Lupdate_loop
+       pshufb BSWAP, DATA
+       movups DATA, (%rdi)
+.Lupdate_just_ret:
+       ret
+
+/*
+ * void clmul_ghash_setkey(be128 *shash, const u8 *key);
+ *
+ * Calculate hash_key << 1 mod poly
+ */
+ENTRY(clmul_ghash_setkey)
+       movaps .Lbswap_mask, BSWAP
+       movups (%rsi), %xmm0
+       pshufb BSWAP, %xmm0
+       movaps %xmm0, %xmm1
+       psllq $1, %xmm0
+       psrlq $63, %xmm1
+       movaps %xmm1, %xmm2
+       pslldq $8, %xmm1
+       psrldq $8, %xmm2
+       por %xmm1, %xmm0
+       # reduction
+       pshufd $0b00100100, %xmm2, %xmm1
+       pcmpeqd .Ltwo_one, %xmm1
+       pand .Lpoly, %xmm1
+       pxor %xmm1, %xmm0
+       movups %xmm0, (%rdi)
+       ret
diff --git a/arch/x86/crypto/ghash-clmulni-intel_glue.c b/arch/x86/crypto/ghash-clmulni-intel_glue.c
new file mode 100644 (file)
index 0000000..65d4096
--- /dev/null
@@ -0,0 +1,333 @@
+/*
+ * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
+ * instructions. This file contains glue code.
+ *
+ * Copyright (c) 2009 Intel Corp.
+ *   Author: Huang Ying <ying.huang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/crypto.h>
+#include <crypto/algapi.h>
+#include <crypto/cryptd.h>
+#include <crypto/gf128mul.h>
+#include <crypto/internal/hash.h>
+#include <asm/i387.h>
+
+#define GHASH_BLOCK_SIZE       16
+#define GHASH_DIGEST_SIZE      16
+
+void clmul_ghash_mul(char *dst, const be128 *shash);
+
+void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
+                       const be128 *shash);
+
+void clmul_ghash_setkey(be128 *shash, const u8 *key);
+
+struct ghash_async_ctx {
+       struct cryptd_ahash *cryptd_tfm;
+};
+
+struct ghash_ctx {
+       be128 shash;
+};
+
+struct ghash_desc_ctx {
+       u8 buffer[GHASH_BLOCK_SIZE];
+       u32 bytes;
+};
+
+static int ghash_init(struct shash_desc *desc)
+{
+       struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+
+       memset(dctx, 0, sizeof(*dctx));
+
+       return 0;
+}
+
+static int ghash_setkey(struct crypto_shash *tfm,
+                       const u8 *key, unsigned int keylen)
+{
+       struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
+
+       if (keylen != GHASH_BLOCK_SIZE) {
+               crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+               return -EINVAL;
+       }
+
+       clmul_ghash_setkey(&ctx->shash, key);
+
+       return 0;
+}
+
+static int ghash_update(struct shash_desc *desc,
+                        const u8 *src, unsigned int srclen)
+{
+       struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+       struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
+       u8 *dst = dctx->buffer;
+
+       kernel_fpu_begin();
+       if (dctx->bytes) {
+               int n = min(srclen, dctx->bytes);
+               u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
+
+               dctx->bytes -= n;
+               srclen -= n;
+
+               while (n--)
+                       *pos++ ^= *src++;
+
+               if (!dctx->bytes)
+                       clmul_ghash_mul(dst, &ctx->shash);
+       }
+
+       clmul_ghash_update(dst, src, srclen, &ctx->shash);
+       kernel_fpu_end();
+
+       if (srclen & 0xf) {
+               src += srclen - (srclen & 0xf);
+               srclen &= 0xf;
+               dctx->bytes = GHASH_BLOCK_SIZE - srclen;
+               while (srclen--)
+                       *dst++ ^= *src++;
+       }
+
+       return 0;
+}
+
+static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
+{
+       u8 *dst = dctx->buffer;
+
+       if (dctx->bytes) {
+               u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
+
+               while (dctx->bytes--)
+                       *tmp++ ^= 0;
+
+               kernel_fpu_begin();
+               clmul_ghash_mul(dst, &ctx->shash);
+               kernel_fpu_end();
+       }
+
+       dctx->bytes = 0;
+}
+
+static int ghash_final(struct shash_desc *desc, u8 *dst)
+{
+       struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+       struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
+       u8 *buf = dctx->buffer;
+
+       ghash_flush(ctx, dctx);
+       memcpy(dst, buf, GHASH_BLOCK_SIZE);
+
+       return 0;
+}
+
+static struct shash_alg ghash_alg = {
+       .digestsize     = GHASH_DIGEST_SIZE,
+       .init           = ghash_init,
+       .update         = ghash_update,
+       .final          = ghash_final,
+       .setkey         = ghash_setkey,
+       .descsize       = sizeof(struct ghash_desc_ctx),
+       .base           = {
+               .cra_name               = "__ghash",
+               .cra_driver_name        = "__ghash-pclmulqdqni",
+               .cra_priority           = 0,
+               .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
+               .cra_blocksize          = GHASH_BLOCK_SIZE,
+               .cra_ctxsize            = sizeof(struct ghash_ctx),
+               .cra_module             = THIS_MODULE,
+               .cra_list               = LIST_HEAD_INIT(ghash_alg.base.cra_list),
+       },
+};
+
+static int ghash_async_init(struct ahash_request *req)
+{
+       struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+       struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+       struct ahash_request *cryptd_req = ahash_request_ctx(req);
+       struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+       if (irq_fpu_usable()) {
+               memcpy(cryptd_req, req, sizeof(*req));
+               ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+               return crypto_ahash_init(cryptd_req);
+       } else {
+               struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+               struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
+
+               desc->tfm = child;
+               desc->flags = req->base.flags;
+               return crypto_shash_init(desc);
+       }
+}
+
+static int ghash_async_update(struct ahash_request *req)
+{
+       struct ahash_request *cryptd_req = ahash_request_ctx(req);
+
+       if (irq_fpu_usable()) {
+               struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+               struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+               struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+               memcpy(cryptd_req, req, sizeof(*req));
+               ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+               return crypto_ahash_update(cryptd_req);
+       } else {
+               struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+               return shash_ahash_update(req, desc);
+       }
+}
+
+static int ghash_async_final(struct ahash_request *req)
+{
+       struct ahash_request *cryptd_req = ahash_request_ctx(req);
+
+       if (irq_fpu_usable()) {
+               struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+               struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+               struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+               memcpy(cryptd_req, req, sizeof(*req));
+               ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+               return crypto_ahash_final(cryptd_req);
+       } else {
+               struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+               return crypto_shash_final(desc, req->result);
+       }
+}
+
+static int ghash_async_digest(struct ahash_request *req)
+{
+       struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+       struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+       struct ahash_request *cryptd_req = ahash_request_ctx(req);
+       struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+       if (irq_fpu_usable()) {
+               memcpy(cryptd_req, req, sizeof(*req));
+               ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+               return crypto_ahash_digest(cryptd_req);
+       } else {
+               struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+               struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
+
+               desc->tfm = child;
+               desc->flags = req->base.flags;
+               return shash_ahash_digest(req, desc);
+       }
+}
+
+static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
+                             unsigned int keylen)
+{
+       struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+       struct crypto_ahash *child = &ctx->cryptd_tfm->base;
+       int err;
+
+       crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+       crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
+                              & CRYPTO_TFM_REQ_MASK);
+       err = crypto_ahash_setkey(child, key, keylen);
+       crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
+                              & CRYPTO_TFM_RES_MASK);
+
+       return 0;
+}
+
+static int ghash_async_init_tfm(struct crypto_tfm *tfm)
+{
+       struct cryptd_ahash *cryptd_tfm;
+       struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
+
+       cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni", 0, 0);
+       if (IS_ERR(cryptd_tfm))
+               return PTR_ERR(cryptd_tfm);
+       ctx->cryptd_tfm = cryptd_tfm;
+       crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
+                                sizeof(struct ahash_request) +
+                                crypto_ahash_reqsize(&cryptd_tfm->base));
+
+       return 0;
+}
+
+static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
+{
+       struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
+
+       cryptd_free_ahash(ctx->cryptd_tfm);
+}
+
+static struct ahash_alg ghash_async_alg = {
+       .init           = ghash_async_init,
+       .update         = ghash_async_update,
+       .final          = ghash_async_final,
+       .setkey         = ghash_async_setkey,
+       .digest         = ghash_async_digest,
+       .halg = {
+               .digestsize     = GHASH_DIGEST_SIZE,
+               .base = {
+                       .cra_name               = "ghash",
+                       .cra_driver_name        = "ghash-clmulni",
+                       .cra_priority           = 400,
+                       .cra_flags              = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
+                       .cra_blocksize          = GHASH_BLOCK_SIZE,
+                       .cra_type               = &crypto_ahash_type,
+                       .cra_module             = THIS_MODULE,
+                       .cra_list               = LIST_HEAD_INIT(ghash_async_alg.halg.base.cra_list),
+                       .cra_init               = ghash_async_init_tfm,
+                       .cra_exit               = ghash_async_exit_tfm,
+               },
+       },
+};
+
+static int __init ghash_pclmulqdqni_mod_init(void)
+{
+       int err;
+
+       if (!cpu_has_pclmulqdq) {
+               printk(KERN_INFO "Intel PCLMULQDQ-NI instructions are not"
+                      " detected.\n");
+               return -ENODEV;
+       }
+
+       err = crypto_register_shash(&ghash_alg);
+       if (err)
+               goto err_out;
+       err = crypto_register_ahash(&ghash_async_alg);
+       if (err)
+               goto err_shash;
+
+       return 0;
+
+err_shash:
+       crypto_unregister_shash(&ghash_alg);
+err_out:
+       return err;
+}
+
+static void __exit ghash_pclmulqdqni_mod_exit(void)
+{
+       crypto_unregister_ahash(&ghash_async_alg);
+       crypto_unregister_shash(&ghash_alg);
+}
+
+module_init(ghash_pclmulqdqni_mod_init);
+module_exit(ghash_pclmulqdqni_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("GHASH Message Digest Algorithm, "
+                  "acclerated by PCLMULQDQ-NI");
+MODULE_ALIAS("ghash");
index 9cfc88b..613700f 100644 (file)
@@ -248,6 +248,7 @@ extern const char * const x86_power_flags[32];
 #define cpu_has_x2apic         boot_cpu_has(X86_FEATURE_X2APIC)
 #define cpu_has_xsave          boot_cpu_has(X86_FEATURE_XSAVE)
 #define cpu_has_hypervisor     boot_cpu_has(X86_FEATURE_HYPERVISOR)
+#define cpu_has_pclmulqdq      boot_cpu_has(X86_FEATURE_PCLMULQDQ)
 
 #if defined(CONFIG_X86_INVLPG) || defined(CONFIG_X86_64)
 # define cpu_has_invlpg                1
index 26b5dd0..fd68711 100644 (file)
@@ -440,6 +440,14 @@ config CRYPTO_WP512
          See also:
          <http://planeta.terra.com.br/informatica/paulobarreto/WhirlpoolPage.html>
 
+config CRYPTO_GHASH_CLMUL_NI_INTEL
+       tristate "GHASH digest algorithm (CLMUL-NI accelerated)"
+       select CRYPTO_SHASH
+       select CRYPTO_CRYPTD
+       help
+         GHASH is message digest algorithm for GCM (Galois/Counter Mode).
+         The implementation is accelerated by CLMUL-NI of Intel.
+
 comment "Ciphers"
 
 config CRYPTO_AES
index 3533582..f8ae0d9 100644 (file)
@@ -711,6 +711,13 @@ struct crypto_shash *cryptd_ahash_child(struct cryptd_ahash *tfm)
 }
 EXPORT_SYMBOL_GPL(cryptd_ahash_child);
 
+struct shash_desc *cryptd_shash_desc(struct ahash_request *req)
+{
+       struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
+       return &rctx->desc;
+}
+EXPORT_SYMBOL_GPL(cryptd_shash_desc);
+
 void cryptd_free_ahash(struct cryptd_ahash *tfm)
 {
        crypto_free_ahash(&tfm->base);
index 2f65a6e..1c96b25 100644 (file)
@@ -39,6 +39,7 @@ static inline struct cryptd_ahash *__cryptd_ahash_cast(
 struct cryptd_ahash *cryptd_alloc_ahash(const char *alg_name,
                                        u32 type, u32 mask);
 struct crypto_shash *cryptd_ahash_child(struct cryptd_ahash *tfm);
+struct shash_desc *cryptd_shash_desc(struct ahash_request *req);
 void cryptd_free_ahash(struct cryptd_ahash *tfm);
 
 #endif