/*
 * Intel SHA Extensions optimized implementation of a SHA-256 update function
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * Contact Information:
 *      Sean Gulley <sean.m.gulley@intel.com>
 *      Tim Chen <tim.c.chen@linux.intel.com>
 *
 * BSD LICENSE
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      * Redistributions of source code must retain the above copyright
 *        notice, this list of conditions and the following disclaimer.
 *      * Redistributions in binary form must reproduce the above copyright
 *        notice, this list of conditions and the following disclaimer in
 *        the documentation and/or other materials provided with the
 *        distribution.
 *      * Neither the name of Intel Corporation nor the names of its
 *        contributors may be used to endorse or promote products derived
 *        from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/*
 * Copyright (c) 2018, Joyent, Inc.
 */

/*
 * illumos uses this file under the terms of the BSD license.
 *
 * The following are a series of changes that we have made to this code:
 *
 *  o Changed the include to be sys/asm_linkage.h.
 *  o Use the sys/asm_linkage.h prototypes for assembly functions.
 *  o Renamed the function from sha256_ni_transform to SHA256TransformBlocks to
 *    match the illumos name for the function.
 *  o The illumos SHA256_CTX does not have the digest as the first member of its
 *    context struct. As such, an offset has to be added to the digest argument
 *    to make sure that we get to the actual digest.
 *  o Update the function prototype block comment to reflect that we are
 *    passing the context and not the direct digest.
 */

#include <sys/asm_linkage.h>

#define DIGEST_PTR      %rdi    /* 1st arg */
#define DATA_PTR        %rsi    /* 2nd arg */
#define NUM_BLKS        %rdx    /* 3rd arg */

#define SHA256CONSTANTS %rax

#define MSG             %xmm0
#define STATE0          %xmm1
#define STATE1          %xmm2
#define MSGTMP0         %xmm3
#define MSGTMP1         %xmm4
#define MSGTMP2         %xmm5
#define MSGTMP3         %xmm6
#define MSGTMP4         %xmm7

#define SHUF_MASK       %xmm8

#define ABEF_SAVE       %xmm9
#define CDGH_SAVE       %xmm10

/*
 * Intel SHA Extensions optimized implementation of a SHA-256 update function
 *
 * The function takes a pointer to the current hash values, a pointer to the
 * input data, and a number of 64 byte blocks to process.  Once all blocks have
 * been processed, the digest pointer is  updated with the resulting hash value.
 * The function only processes complete blocks, there is no functionality to
 * store partial blocks.  All message padding and hash value initialization must
 * be done outside the update function.
 *
 * The indented lines in the loop are instructions related to rounds processing.
 * The non-indented lines are instructions related to the message schedule.
 *
 * void SHA256TransformBlocks(SHA256_CTX *ctx, const void *data,
                uint32_t numBlocks);
 * digest : pointer to digest
 * data: pointer to input data
 * numBlocks: Number of blocks to process
 */

.text
.align 32
ENTRY_NP(SHA256TransformBlocks)

        shl             $6, NUM_BLKS            /* convert to bytes */
        jz              .Ldone_hash
        add             DATA_PTR, NUM_BLKS      /* pointer to end of data */

        /*
         * load initial hash values
         * Need to reorder these appropriately
         * DCBA, HGFE -> ABEF, CDGH
         *
         * Offset DIGEST_PTR to account for the algorithm in the context.
         */
        addq            $8, DIGEST_PTR
        movdqu          0*16(DIGEST_PTR), STATE0
        movdqu          1*16(DIGEST_PTR), STATE1

        pshufd          $0xB1, STATE0,  STATE0          /* CDAB */
        pshufd          $0x1B, STATE1,  STATE1          /* EFGH */
        movdqa          STATE0, MSGTMP4
        palignr         $8, STATE1,  STATE0             /* ABEF */
        pblendw         $0xF0, MSGTMP4, STATE1          /* CDGH */

        movdqa          PSHUFFLE_BYTE_FLIP_MASK(%rip), SHUF_MASK
        lea             K256(%rip), SHA256CONSTANTS

.Lloop0:
        /* Save hash values for addition after rounds */
        movdqa          STATE0, ABEF_SAVE
        movdqa          STATE1, CDGH_SAVE

        /* Rounds 0-3 */
        movdqu          0*16(DATA_PTR), MSG
        pshufb          SHUF_MASK, MSG
        movdqa          MSG, MSGTMP0
                paddd           0*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0

        /* Rounds 4-7 */
        movdqu          1*16(DATA_PTR), MSG
        pshufb          SHUF_MASK, MSG
        movdqa          MSG, MSGTMP1
                paddd           1*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP1, MSGTMP0

        /* Rounds 8-11 */
        movdqu          2*16(DATA_PTR), MSG
        pshufb          SHUF_MASK, MSG
        movdqa          MSG, MSGTMP2
                paddd           2*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP2, MSGTMP1

        /* Rounds 12-15 */
        movdqu          3*16(DATA_PTR), MSG
        pshufb          SHUF_MASK, MSG
        movdqa          MSG, MSGTMP3
                paddd           3*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP3, MSGTMP4
        palignr         $4, MSGTMP2, MSGTMP4
        paddd           MSGTMP4, MSGTMP0
        sha256msg2      MSGTMP3, MSGTMP0
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP3, MSGTMP2

        /* Rounds 16-19 */
        movdqa          MSGTMP0, MSG
                paddd           4*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP0, MSGTMP4
        palignr         $4, MSGTMP3, MSGTMP4
        paddd           MSGTMP4, MSGTMP1
        sha256msg2      MSGTMP0, MSGTMP1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP0, MSGTMP3

        /* Rounds 20-23 */
        movdqa          MSGTMP1, MSG
                paddd           5*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP1, MSGTMP4
        palignr         $4, MSGTMP0, MSGTMP4
        paddd           MSGTMP4, MSGTMP2
        sha256msg2      MSGTMP1, MSGTMP2
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP1, MSGTMP0

        /* Rounds 24-27 */
        movdqa          MSGTMP2, MSG
                paddd           6*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP2, MSGTMP4
        palignr         $4, MSGTMP1, MSGTMP4
        paddd           MSGTMP4, MSGTMP3
        sha256msg2      MSGTMP2, MSGTMP3
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP2, MSGTMP1

        /* Rounds 28-31 */
        movdqa          MSGTMP3, MSG
                paddd           7*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP3, MSGTMP4
        palignr         $4, MSGTMP2, MSGTMP4
        paddd           MSGTMP4, MSGTMP0
        sha256msg2      MSGTMP3, MSGTMP0
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP3, MSGTMP2

        /* Rounds 32-35 */
        movdqa          MSGTMP0, MSG
                paddd           8*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP0, MSGTMP4
        palignr         $4, MSGTMP3, MSGTMP4
        paddd           MSGTMP4, MSGTMP1
        sha256msg2      MSGTMP0, MSGTMP1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP0, MSGTMP3

        /* Rounds 36-39 */
        movdqa          MSGTMP1, MSG
                paddd           9*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP1, MSGTMP4
        palignr         $4, MSGTMP0, MSGTMP4
        paddd           MSGTMP4, MSGTMP2
        sha256msg2      MSGTMP1, MSGTMP2
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP1, MSGTMP0

        /* Rounds 40-43 */
        movdqa          MSGTMP2, MSG
                paddd           10*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP2, MSGTMP4
        palignr         $4, MSGTMP1, MSGTMP4
        paddd           MSGTMP4, MSGTMP3
        sha256msg2      MSGTMP2, MSGTMP3
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP2, MSGTMP1

        /* Rounds 44-47 */
        movdqa          MSGTMP3, MSG
                paddd           11*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP3, MSGTMP4
        palignr         $4, MSGTMP2, MSGTMP4
        paddd           MSGTMP4, MSGTMP0
        sha256msg2      MSGTMP3, MSGTMP0
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP3, MSGTMP2

        /* Rounds 48-51 */
        movdqa          MSGTMP0, MSG
                paddd           12*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP0, MSGTMP4
        palignr         $4, MSGTMP3, MSGTMP4
        paddd           MSGTMP4, MSGTMP1
        sha256msg2      MSGTMP0, MSGTMP1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0
        sha256msg1      MSGTMP0, MSGTMP3

        /* Rounds 52-55 */
        movdqa          MSGTMP1, MSG
                paddd           13*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP1, MSGTMP4
        palignr         $4, MSGTMP0, MSGTMP4
        paddd           MSGTMP4, MSGTMP2
        sha256msg2      MSGTMP1, MSGTMP2
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0

        /* Rounds 56-59 */
        movdqa          MSGTMP2, MSG
                paddd           14*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
        movdqa          MSGTMP2, MSGTMP4
        palignr         $4, MSGTMP1, MSGTMP4
        paddd           MSGTMP4, MSGTMP3
        sha256msg2      MSGTMP2, MSGTMP3
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0

        /* Rounds 60-63 */
        movdqa          MSGTMP3, MSG
                paddd           15*16(SHA256CONSTANTS), MSG
                sha256rnds2     STATE0, STATE1
                pshufd          $0x0E, MSG, MSG
                sha256rnds2     STATE1, STATE0

        /* Add current hash values with previously saved */
        paddd           ABEF_SAVE, STATE0
        paddd           CDGH_SAVE, STATE1

        /* Increment data pointer and loop if more to process */
        add             $64, DATA_PTR
        cmp             NUM_BLKS, DATA_PTR
        jne             .Lloop0

        /* Write hash values back in the correct order */
        pshufd          $0x1B, STATE0,  STATE0          /* FEBA */
        pshufd          $0xB1, STATE1,  STATE1          /* DCHG */
        movdqa          STATE0, MSGTMP4
        pblendw         $0xF0, STATE1,  STATE0          /* DCBA */
        palignr         $8, MSGTMP4, STATE1             /* HGFE */

        movdqu          STATE0, 0*16(DIGEST_PTR)
        movdqu          STATE1, 1*16(DIGEST_PTR)

.Ldone_hash:

        ret
SET_SIZE(SHA256TransformBlocks)

.section        .rodata.cst256.K256, "aM", @progbits, 256
.align 64
K256:
        .long   0x428a2f98,0x71374491,0xb5c0fbcf,0xe9b5dba5
        .long   0x3956c25b,0x59f111f1,0x923f82a4,0xab1c5ed5
        .long   0xd807aa98,0x12835b01,0x243185be,0x550c7dc3
        .long   0x72be5d74,0x80deb1fe,0x9bdc06a7,0xc19bf174
        .long   0xe49b69c1,0xefbe4786,0x0fc19dc6,0x240ca1cc
        .long   0x2de92c6f,0x4a7484aa,0x5cb0a9dc,0x76f988da
        .long   0x983e5152,0xa831c66d,0xb00327c8,0xbf597fc7
        .long   0xc6e00bf3,0xd5a79147,0x06ca6351,0x14292967
        .long   0x27b70a85,0x2e1b2138,0x4d2c6dfc,0x53380d13
        .long   0x650a7354,0x766a0abb,0x81c2c92e,0x92722c85
        .long   0xa2bfe8a1,0xa81a664b,0xc24b8b70,0xc76c51a3
        .long   0xd192e819,0xd6990624,0xf40e3585,0x106aa070
        .long   0x19a4c116,0x1e376c08,0x2748774c,0x34b0bcb5
        .long   0x391c0cb3,0x4ed8aa4a,0x5b9cca4f,0x682e6ff3
        .long   0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208
        .long   0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2

.section        .rodata.cst16.PSHUFFLE_BYTE_FLIP_MASK, "aM", @progbits, 16
.align 16
PSHUFFLE_BYTE_FLIP_MASK:
        .octa 0x0c0d0e0f08090a0b0405060700010203