mirror_zfs/module/icp/asm-x86_64/modes/gcm_intel.S
Tom Caputi 0b04990a5d Illumos Crypto Port module added to enable native encryption in zfs
A port of the Illumos Crypto Framework to a Linux kernel module (found
in module/icp). This is needed to do the actual encryption work. We cannot
use the Linux kernel's built in crypto api because it is only exported to
GPL-licensed modules. Having the ICP also means the crypto code can run on
any of the other kernels under OpenZFS. I ended up porting over most of the
internals of the framework, which means that porting over other API calls (if
we need them) should be fairly easy. Specifically, I have ported over the API
functions related to encryption, digests, macs, and crypto templates. The ICP
is able to use assembly-accelerated encryption on amd64 machines and AES-NI
instructions on Intel chips that support it. There are place-holder
directories for similar assembly optimizations for other architectures
(although they have not been written).

Signed-off-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4329
2016-07-20 10:43:30 -07:00

335 lines
9.0 KiB
ArmAsm

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2009 Intel Corporation
* All Rights Reserved.
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Accelerated GHASH implementation with Intel PCLMULQDQ-NI
* instructions. This file contains an accelerated
* Galois Field Multiplication 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/
*
*/
/*
* ====================================================================
* OpenSolaris OS modifications
*
* This source originates as file galois_hash_asm.c from
* Intel Corporation dated September 21, 2009.
*
* This OpenSolaris version has these major changes from the original source:
*
* 1. Added OpenSolaris ENTRY_NP/SET_SIZE macros from
* /usr/include/sys/asm_linkage.h, lint(1B) guards, and a dummy C function
* definition for lint.
*
* 2. Formatted code, added comments, and added #includes and #defines.
*
* 3. If bit CR0.TS is set, clear and set the TS bit, after and before
* calling kpreempt_disable() and kpreempt_enable().
* If the TS bit is not set, Save and restore %xmm registers at the beginning
* and end of function calls (%xmm* registers are not saved and restored by
* during kernel thread preemption).
*
* 4. Removed code to perform hashing. This is already done with C macro
* GHASH in gcm.c. For better performance, this removed code should be
* reintegrated in the future to replace the C GHASH macro.
*
* 5. Added code to byte swap 16-byte input and output.
*
* 6. Folded in comments from the original C source with embedded assembly
* (SB_w_shift_xor.c)
*
* 7. Renamed function and reordered parameters to match OpenSolaris:
* Intel interface:
* void galois_hash_asm(unsigned char *hk, unsigned char *s,
* unsigned char *d, int length)
* OpenSolaris OS interface:
* void gcm_mul_pclmulqdq(uint64_t *x_in, uint64_t *y, uint64_t *res);
* ====================================================================
*/
#if defined(lint) || defined(__lint)
#include <sys/types.h>
/* ARGSUSED */
void
gcm_mul_pclmulqdq(uint64_t *x_in, uint64_t *y, uint64_t *res) {
}
#else /* lint */
#define _ASM
#include <sys/asm_linkage.h>
#ifdef _KERNEL
/*
* Note: the CLTS macro clobbers P2 (%rsi) under i86xpv. That is,
* it calls HYPERVISOR_fpu_taskswitch() which modifies %rsi when it
* uses it to pass P2 to syscall.
* This also occurs with the STTS macro, but we dont care if
* P2 (%rsi) is modified just before function exit.
* The CLTS and STTS macros push and pop P1 (%rdi) already.
*/
#ifdef __xpv
#define PROTECTED_CLTS \
push %rsi; \
CLTS; \
pop %rsi
#else
#define PROTECTED_CLTS \
CLTS
#endif /* __xpv */
/*
* If CR0_TS is not set, align stack (with push %rbp) and push
* %xmm0 - %xmm10 on stack, otherwise clear CR0_TS
*/
#define CLEAR_TS_OR_PUSH_XMM_REGISTERS(tmpreg) \
push %rbp; \
mov %rsp, %rbp; \
movq %cr0, tmpreg; \
testq $CR0_TS, tmpreg; \
jnz 1f; \
and $-XMM_ALIGN, %rsp; \
sub $[XMM_SIZE * 11], %rsp; \
movaps %xmm0, 160(%rsp); \
movaps %xmm1, 144(%rsp); \
movaps %xmm2, 128(%rsp); \
movaps %xmm3, 112(%rsp); \
movaps %xmm4, 96(%rsp); \
movaps %xmm5, 80(%rsp); \
movaps %xmm6, 64(%rsp); \
movaps %xmm7, 48(%rsp); \
movaps %xmm8, 32(%rsp); \
movaps %xmm9, 16(%rsp); \
movaps %xmm10, (%rsp); \
jmp 2f; \
1: \
PROTECTED_CLTS; \
2:
/*
* If CR0_TS was not set above, pop %xmm0 - %xmm10 off stack,
* otherwise set CR0_TS.
*/
#define SET_TS_OR_POP_XMM_REGISTERS(tmpreg) \
testq $CR0_TS, tmpreg; \
jnz 1f; \
movaps (%rsp), %xmm10; \
movaps 16(%rsp), %xmm9; \
movaps 32(%rsp), %xmm8; \
movaps 48(%rsp), %xmm7; \
movaps 64(%rsp), %xmm6; \
movaps 80(%rsp), %xmm5; \
movaps 96(%rsp), %xmm4; \
movaps 112(%rsp), %xmm3; \
movaps 128(%rsp), %xmm2; \
movaps 144(%rsp), %xmm1; \
movaps 160(%rsp), %xmm0; \
jmp 2f; \
1: \
STTS(tmpreg); \
2: \
mov %rbp, %rsp; \
pop %rbp
#else
#define PROTECTED_CLTS
#define CLEAR_TS_OR_PUSH_XMM_REGISTERS(tmpreg)
#define SET_TS_OR_POP_XMM_REGISTERS(tmpreg)
#endif /* _KERNEL */
/*
* Use this mask to byte-swap a 16-byte integer with the pshufb instruction
*/
// static uint8_t byte_swap16_mask[] = {
// 15, 14, 13, 12, 11, 10, 9, 8, 7, 6 ,5, 4, 3, 2, 1, 0 };
.text
.align XMM_ALIGN
.Lbyte_swap16_mask:
.byte 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
/*
* void gcm_mul_pclmulqdq(uint64_t *x_in, uint64_t *y, uint64_t *res);
*
* Perform a carry-less multiplication (that is, use XOR instead of the
* multiply operator) on P1 and P2 and place the result in P3.
*
* Byte swap the input and the output.
*
* Note: x_in, y, and res all point to a block of 20-byte numbers
* (an array of two 64-bit integers).
*
* Note2: For kernel code, caller is responsible for ensuring
* kpreempt_disable() has been called. This is because %xmm registers are
* not saved/restored. Clear and set the CR0.TS bit on entry and exit,
* respectively, if TS is set on entry. Otherwise, if TS is not set,
* save and restore %xmm registers on the stack.
*
* Note3: Original Intel definition:
* void galois_hash_asm(unsigned char *hk, unsigned char *s,
* unsigned char *d, int length)
*
* Note4: Register/parameter mapping:
* Intel:
* Parameter 1: %rcx (copied to %xmm0) hk or x_in
* Parameter 2: %rdx (copied to %xmm1) s or y
* Parameter 3: %rdi (result) d or res
* OpenSolaris:
* Parameter 1: %rdi (copied to %xmm0) x_in
* Parameter 2: %rsi (copied to %xmm1) y
* Parameter 3: %rdx (result) res
*/
ENTRY_NP(gcm_mul_pclmulqdq)
CLEAR_TS_OR_PUSH_XMM_REGISTERS(%r10)
//
// Copy Parameters
//
movdqu (%rdi), %xmm0 // P1
movdqu (%rsi), %xmm1 // P2
//
// Byte swap 16-byte input
//
lea .Lbyte_swap16_mask(%rip), %rax
movaps (%rax), %xmm10
pshufb %xmm10, %xmm0
pshufb %xmm10, %xmm1
//
// Multiply with the hash key
//
movdqu %xmm0, %xmm3
pclmulqdq $0, %xmm1, %xmm3 // xmm3 holds a0*b0
movdqu %xmm0, %xmm4
pclmulqdq $16, %xmm1, %xmm4 // xmm4 holds a0*b1
movdqu %xmm0, %xmm5
pclmulqdq $1, %xmm1, %xmm5 // xmm5 holds a1*b0
movdqu %xmm0, %xmm6
pclmulqdq $17, %xmm1, %xmm6 // xmm6 holds a1*b1
pxor %xmm5, %xmm4 // xmm4 holds a0*b1 + a1*b0
movdqu %xmm4, %xmm5 // move the contents of xmm4 to xmm5
psrldq $8, %xmm4 // shift by xmm4 64 bits to the right
pslldq $8, %xmm5 // shift by xmm5 64 bits to the left
pxor %xmm5, %xmm3
pxor %xmm4, %xmm6 // Register pair <xmm6:xmm3> holds the result
// of the carry-less multiplication of
// xmm0 by xmm1.
// We shift the result of the multiplication by one bit position
// to the left to cope for the fact that the bits are reversed.
movdqu %xmm3, %xmm7
movdqu %xmm6, %xmm8
pslld $1, %xmm3
pslld $1, %xmm6
psrld $31, %xmm7
psrld $31, %xmm8
movdqu %xmm7, %xmm9
pslldq $4, %xmm8
pslldq $4, %xmm7
psrldq $12, %xmm9
por %xmm7, %xmm3
por %xmm8, %xmm6
por %xmm9, %xmm6
//
// First phase of the reduction
//
// Move xmm3 into xmm7, xmm8, xmm9 in order to perform the shifts
// independently.
movdqu %xmm3, %xmm7
movdqu %xmm3, %xmm8
movdqu %xmm3, %xmm9
pslld $31, %xmm7 // packed right shift shifting << 31
pslld $30, %xmm8 // packed right shift shifting << 30
pslld $25, %xmm9 // packed right shift shifting << 25
pxor %xmm8, %xmm7 // xor the shifted versions
pxor %xmm9, %xmm7
movdqu %xmm7, %xmm8
pslldq $12, %xmm7
psrldq $4, %xmm8
pxor %xmm7, %xmm3 // first phase of the reduction complete
//
// Second phase of the reduction
//
// Make 3 copies of xmm3 in xmm2, xmm4, xmm5 for doing these
// shift operations.
movdqu %xmm3, %xmm2
movdqu %xmm3, %xmm4 // packed left shifting >> 1
movdqu %xmm3, %xmm5
psrld $1, %xmm2
psrld $2, %xmm4 // packed left shifting >> 2
psrld $7, %xmm5 // packed left shifting >> 7
pxor %xmm4, %xmm2 // xor the shifted versions
pxor %xmm5, %xmm2
pxor %xmm8, %xmm2
pxor %xmm2, %xmm3
pxor %xmm3, %xmm6 // the result is in xmm6
//
// Byte swap 16-byte result
//
pshufb %xmm10, %xmm6 // %xmm10 has the swap mask
//
// Store the result
//
movdqu %xmm6, (%rdx) // P3
//
// Cleanup and Return
//
SET_TS_OR_POP_XMM_REGISTERS(%r10)
ret
SET_SIZE(gcm_mul_pclmulqdq)
#endif /* lint || __lint */