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authorHuang Ying <ying.huang@intel.com>2009-10-19 11:53:06 +0900
committerHerbert Xu <herbert@gondor.apana.org.au>2009-10-19 11:53:06 +0900
commit0e1227d356e9b2fe0500d6cc7084f752040a1e0e (patch)
tree6f059b8e3c31539942ad244e7aadabcb54e8d904
parent4c6ab3ee4cdb86cbd4e9400dd22fad7701cbe795 (diff)
downloadop-kernel-dev-0e1227d356e9b2fe0500d6cc7084f752040a1e0e.zip
op-kernel-dev-0e1227d356e9b2fe0500d6cc7084f752040a1e0e.tar.gz
crypto: ghash - Add PCLMULQDQ accelerated implementation
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>
-rw-r--r--arch/x86/crypto/Makefile3
-rw-r--r--arch/x86/crypto/ghash-clmulni-intel_asm.S157
-rw-r--r--arch/x86/crypto/ghash-clmulni-intel_glue.c333
-rw-r--r--arch/x86/include/asm/cpufeature.h1
-rw-r--r--crypto/Kconfig8
-rw-r--r--crypto/cryptd.c7
-rw-r--r--include/crypto/cryptd.h1
7 files changed, 510 insertions, 0 deletions
diff --git a/arch/x86/crypto/Makefile b/arch/x86/crypto/Makefile
index cfb0010..1a58ad8 100644
--- a/arch/x86/crypto/Makefile
+++ b/arch/x86/crypto/Makefile
@@ -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
index 0000000..b9e787a
--- /dev/null
+++ b/arch/x86/crypto/ghash-clmulni-intel_asm.S
@@ -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
index 0000000..65d4096
--- /dev/null
+++ b/arch/x86/crypto/ghash-clmulni-intel_glue.c
@@ -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");
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 9cfc88b..613700f 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -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
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 26b5dd0..fd68711 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -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
diff --git a/crypto/cryptd.c b/crypto/cryptd.c
index 3533582..f8ae0d9 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -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);
diff --git a/include/crypto/cryptd.h b/include/crypto/cryptd.h
index 2f65a6e..1c96b25 100644
--- a/include/crypto/cryptd.h
+++ b/include/crypto/cryptd.h
@@ -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
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