/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:4;coding:utf-8 -*-â
âvi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :viâ
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â Copyright The Mbed TLS Contributors                                          â
â                                                                              â
â Licensed under the Apache License, Version 2.0 (the "License");              â
â you may not use this file except in compliance with the License.             â
â You may obtain a copy of the License at                                      â
â                                                                              â
â     http://www.apache.org/licenses/LICENSE-2.0                               â
â                                                                              â
â Unless required by applicable law or agreed to in writing, software          â
â distributed under the License is distributed on an "AS IS" BASIS,            â
â WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.     â
â See the License for the specific language governing permissions and          â
â limitations under the License.                                               â
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#include "libc/intrin/asan.internal.h"
#include "libc/intrin/bits.h"
#include "libc/macros.internal.h"
#include "libc/nexgen32e/sha.h"
#include "libc/nexgen32e/x86feature.h"
#include "libc/str/str.h"
#include "third_party/mbedtls/common.h"
#include "third_party/mbedtls/endian.h"
#include "third_party/mbedtls/error.h"
#include "third_party/mbedtls/md.h"
#include "third_party/mbedtls/platform.h"
#include "third_party/mbedtls/sha1.h"

asm(".ident\t\"\\n\\n\
Mbed TLS (Apache 2.0)\\n\
Copyright ARM Limited\\n\
Copyright Mbed TLS Contributors\"");
asm(".include \"libc/disclaimer.inc\"");
/* clang-format off */

/**
 * @fileoverview FIPS-180-1 compliant SHA-1 implementation
 *
 * The SHA-1 standard was published by NIST in 1993.
 *
 * @see http://www.itl.nist.gov/fipspubs/fip180-1.htm
 */

#define SHA1_VALIDATE_RET(cond)                             \
    MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_SHA1_BAD_INPUT_DATA )

#define SHA1_VALIDATE(cond)  MBEDTLS_INTERNAL_VALIDATE( cond )

/**
 * \brief          This function clones the state of a SHA-1 context.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param dst      The SHA-1 context to clone to. This must be initialized.
 * \param src      The SHA-1 context to clone from. This must be initialized.
 *
 */
void mbedtls_sha1_clone( mbedtls_sha1_context *dst,
                         const mbedtls_sha1_context *src )
{
    SHA1_VALIDATE( dst != NULL );
    SHA1_VALIDATE( src != NULL );
    *dst = *src;
}

/**
 * \brief          This function starts a SHA-1 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to initialize. This must be initialized.
 *
 * \return         \c 0 on success.
 * \return         A negative error code on failure.
 *
 */
int mbedtls_sha1_starts_ret( mbedtls_sha1_context *ctx )
{
    SHA1_VALIDATE_RET( ctx != NULL );
    ctx->total[0] = 0;
    ctx->total[1] = 0;
    ctx->state[0] = 0x67452301;
    ctx->state[1] = 0xEFCDAB89;
    ctx->state[2] = 0x98BADCFE;
    ctx->state[3] = 0x10325476;
    ctx->state[4] = 0xC3D2E1F0;
    return( 0 );
}

#if !defined(MBEDTLS_SHA1_PROCESS_ALT)
/**
 * \brief          SHA-1 process data block (internal use only).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to use. This must be initialized.
 * \param data     The data block being processed. This must be a
 *                 readable buffer of length \c 64 Bytes.
 *
 * \return         \c 0 on success.
 * \return         A negative error code on failure.
 *
 */
int mbedtls_internal_sha1_process( mbedtls_sha1_context *ctx,
                                   const unsigned char data[64] )
{
    SHA1_VALIDATE_RET( ctx != NULL );
    SHA1_VALIDATE_RET( (const unsigned char *)data != NULL );

    if( !IsTiny() || X86_NEED( SHA ) )
    {
        if( X86_HAVE( SHA ) )
        {
            if( IsAsan() )
            {
                __asan_verify( data, 64 );
                __asan_verify( ctx, sizeof(*ctx) );
            }
            sha1_transform_ni( ctx->state, data, 1 );
            return( 0 );
        }
        if( X86_HAVE( BMI  ) &&
            X86_HAVE( BMI2 ) &&
            X86_HAVE( AVX2 ) )
        {
            if( IsAsan() )
            {
                __asan_verify( data, 64 );
                __asan_verify( ctx, sizeof(*ctx) );
            }
            sha1_transform_avx2( ctx->state, data, 1 );
            return( 0 );
        }
    }

#ifdef MBEDTLS_SHA1_SMALLER
#define ROL(a, b) ((a << b) | (a >> (32 - b)))

    uint32_t a, b, c, d, e, i, j, t, m[80];
    for (i = 0, j = 0; i < 16; ++i, j += 4) {
        m[i] = READ32BE(data + j);
    }
    for (; i < 80; ++i) {
        m[i] = (m[i - 3] ^ m[i - 8] ^ m[i - 14] ^ m[i - 16]);
        m[i] = (m[i] << 1) | (m[i] >> 31);
    }
    a = ctx->state[0];
    b = ctx->state[1];
    c = ctx->state[2];
    d = ctx->state[3];
    e = ctx->state[4];
    for (i = 0; i < 20; ++i) {
        t = ROL(a, 5) + ((b & c) ^ (~b & d)) + e + 0x5a827999 + m[i];
        e = d, d = c;
        c = ROL(b, 30);
        b = a, a = t;
    }
    for (; i < 40; ++i) {
        t = ROL(a, 5) + (b ^ c ^ d) + e + 0x6ed9eba1 + m[i];
        e = d, d = c;
        c = ROL(b, 30);
        b = a, a = t;
    }
    for (; i < 60; ++i) {
        t = ROL(a, 5) + ((b & c) ^ (b & d) ^ (c & d)) + e + 0x8f1bbcdc + m[i];
        e = d, d = c;
        c = ROL(b, 30);
        b = a, a = t;
    }
    for (; i < 80; ++i) {
        t = ROL(a, 5) + (b ^ c ^ d) + e + 0xca62c1d6 + m[i];
        e = d, d = c;
        c = ROL(b, 30);
        b = a, a = t;
    }
    ctx->state[0] += a;
    ctx->state[1] += b;
    ctx->state[2] += c;
    ctx->state[3] += d;
    ctx->state[4] += e;

    mbedtls_platform_zeroize(m, sizeof(m));

#else

    struct
    {
        uint32_t temp, W[16], A, B, C, D, E;
    } local;

    GET_UINT32_BE( local.W[ 0], data,  0 );
    GET_UINT32_BE( local.W[ 1], data,  4 );
    GET_UINT32_BE( local.W[ 2], data,  8 );
    GET_UINT32_BE( local.W[ 3], data, 12 );
    GET_UINT32_BE( local.W[ 4], data, 16 );
    GET_UINT32_BE( local.W[ 5], data, 20 );
    GET_UINT32_BE( local.W[ 6], data, 24 );
    GET_UINT32_BE( local.W[ 7], data, 28 );
    GET_UINT32_BE( local.W[ 8], data, 32 );
    GET_UINT32_BE( local.W[ 9], data, 36 );
    GET_UINT32_BE( local.W[10], data, 40 );
    GET_UINT32_BE( local.W[11], data, 44 );
    GET_UINT32_BE( local.W[12], data, 48 );
    GET_UINT32_BE( local.W[13], data, 52 );
    GET_UINT32_BE( local.W[14], data, 56 );
    GET_UINT32_BE( local.W[15], data, 60 );

#define S(x,n) (((x) << (n)) | (((x) & 0xFFFFFFFF) >> (32 - (n))))

#define R(t)                                                    \
    (                                                           \
        local.temp = local.W[( (t) -  3 ) & 0x0F] ^             \
                     local.W[( (t) -  8 ) & 0x0F] ^             \
                     local.W[( (t) - 14 ) & 0x0F] ^             \
                     local.W[  (t)        & 0x0F],              \
        ( local.W[(t) & 0x0F] = S(local.temp,1) )               \
    )

#define P(a,b,c,d,e,x)                                          \
    do                                                          \
    {                                                           \
        (e) += S((a),5) + F((b),(c),(d)) + K + (x);             \
        (b) = S((b),30);                                        \
    } while( 0 )

    local.A = ctx->state[0];
    local.B = ctx->state[1];
    local.C = ctx->state[2];
    local.D = ctx->state[3];
    local.E = ctx->state[4];

#define F(x,y,z) ((z) ^ ((x) & ((y) ^ (z))))
#define K 0x5A827999

    P( local.A, local.B, local.C, local.D, local.E, local.W[0]  );
    P( local.E, local.A, local.B, local.C, local.D, local.W[1]  );
    P( local.D, local.E, local.A, local.B, local.C, local.W[2]  );
    P( local.C, local.D, local.E, local.A, local.B, local.W[3]  );
    P( local.B, local.C, local.D, local.E, local.A, local.W[4]  );
    P( local.A, local.B, local.C, local.D, local.E, local.W[5]  );
    P( local.E, local.A, local.B, local.C, local.D, local.W[6]  );
    P( local.D, local.E, local.A, local.B, local.C, local.W[7]  );
    P( local.C, local.D, local.E, local.A, local.B, local.W[8]  );
    P( local.B, local.C, local.D, local.E, local.A, local.W[9]  );
    P( local.A, local.B, local.C, local.D, local.E, local.W[10] );
    P( local.E, local.A, local.B, local.C, local.D, local.W[11] );
    P( local.D, local.E, local.A, local.B, local.C, local.W[12] );
    P( local.C, local.D, local.E, local.A, local.B, local.W[13] );
    P( local.B, local.C, local.D, local.E, local.A, local.W[14] );
    P( local.A, local.B, local.C, local.D, local.E, local.W[15] );
    P( local.E, local.A, local.B, local.C, local.D, R(16) );
    P( local.D, local.E, local.A, local.B, local.C, R(17) );
    P( local.C, local.D, local.E, local.A, local.B, R(18) );
    P( local.B, local.C, local.D, local.E, local.A, R(19) );

#undef K
#undef F

#define F(x,y,z) ((x) ^ (y) ^ (z))
#define K 0x6ED9EBA1

    P( local.A, local.B, local.C, local.D, local.E, R(20) );
    P( local.E, local.A, local.B, local.C, local.D, R(21) );
    P( local.D, local.E, local.A, local.B, local.C, R(22) );
    P( local.C, local.D, local.E, local.A, local.B, R(23) );
    P( local.B, local.C, local.D, local.E, local.A, R(24) );
    P( local.A, local.B, local.C, local.D, local.E, R(25) );
    P( local.E, local.A, local.B, local.C, local.D, R(26) );
    P( local.D, local.E, local.A, local.B, local.C, R(27) );
    P( local.C, local.D, local.E, local.A, local.B, R(28) );
    P( local.B, local.C, local.D, local.E, local.A, R(29) );
    P( local.A, local.B, local.C, local.D, local.E, R(30) );
    P( local.E, local.A, local.B, local.C, local.D, R(31) );
    P( local.D, local.E, local.A, local.B, local.C, R(32) );
    P( local.C, local.D, local.E, local.A, local.B, R(33) );
    P( local.B, local.C, local.D, local.E, local.A, R(34) );
    P( local.A, local.B, local.C, local.D, local.E, R(35) );
    P( local.E, local.A, local.B, local.C, local.D, R(36) );
    P( local.D, local.E, local.A, local.B, local.C, R(37) );
    P( local.C, local.D, local.E, local.A, local.B, R(38) );
    P( local.B, local.C, local.D, local.E, local.A, R(39) );

#undef K
#undef F

#define F(x,y,z) (((x) & (y)) | ((z) & ((x) | (y))))
#define K 0x8F1BBCDC

    P( local.A, local.B, local.C, local.D, local.E, R(40) );
    P( local.E, local.A, local.B, local.C, local.D, R(41) );
    P( local.D, local.E, local.A, local.B, local.C, R(42) );
    P( local.C, local.D, local.E, local.A, local.B, R(43) );
    P( local.B, local.C, local.D, local.E, local.A, R(44) );
    P( local.A, local.B, local.C, local.D, local.E, R(45) );
    P( local.E, local.A, local.B, local.C, local.D, R(46) );
    P( local.D, local.E, local.A, local.B, local.C, R(47) );
    P( local.C, local.D, local.E, local.A, local.B, R(48) );
    P( local.B, local.C, local.D, local.E, local.A, R(49) );
    P( local.A, local.B, local.C, local.D, local.E, R(50) );
    P( local.E, local.A, local.B, local.C, local.D, R(51) );
    P( local.D, local.E, local.A, local.B, local.C, R(52) );
    P( local.C, local.D, local.E, local.A, local.B, R(53) );
    P( local.B, local.C, local.D, local.E, local.A, R(54) );
    P( local.A, local.B, local.C, local.D, local.E, R(55) );
    P( local.E, local.A, local.B, local.C, local.D, R(56) );
    P( local.D, local.E, local.A, local.B, local.C, R(57) );
    P( local.C, local.D, local.E, local.A, local.B, R(58) );
    P( local.B, local.C, local.D, local.E, local.A, R(59) );

#undef K
#undef F

#define F(x,y,z) ((x) ^ (y) ^ (z))
#define K 0xCA62C1D6

    P( local.A, local.B, local.C, local.D, local.E, R(60) );
    P( local.E, local.A, local.B, local.C, local.D, R(61) );
    P( local.D, local.E, local.A, local.B, local.C, R(62) );
    P( local.C, local.D, local.E, local.A, local.B, R(63) );
    P( local.B, local.C, local.D, local.E, local.A, R(64) );
    P( local.A, local.B, local.C, local.D, local.E, R(65) );
    P( local.E, local.A, local.B, local.C, local.D, R(66) );
    P( local.D, local.E, local.A, local.B, local.C, R(67) );
    P( local.C, local.D, local.E, local.A, local.B, R(68) );
    P( local.B, local.C, local.D, local.E, local.A, R(69) );
    P( local.A, local.B, local.C, local.D, local.E, R(70) );
    P( local.E, local.A, local.B, local.C, local.D, R(71) );
    P( local.D, local.E, local.A, local.B, local.C, R(72) );
    P( local.C, local.D, local.E, local.A, local.B, R(73) );
    P( local.B, local.C, local.D, local.E, local.A, R(74) );
    P( local.A, local.B, local.C, local.D, local.E, R(75) );
    P( local.E, local.A, local.B, local.C, local.D, R(76) );
    P( local.D, local.E, local.A, local.B, local.C, R(77) );
    P( local.C, local.D, local.E, local.A, local.B, R(78) );
    P( local.B, local.C, local.D, local.E, local.A, R(79) );

#undef K
#undef F

    ctx->state[0] += local.A;
    ctx->state[1] += local.B;
    ctx->state[2] += local.C;
    ctx->state[3] += local.D;
    ctx->state[4] += local.E;

    /* Zeroise buffers and variables to clear sensitive data from memory. */
    mbedtls_platform_zeroize( &local, sizeof( local ) );

#endif /* MBEDTLS_SHA1_SMALLER */

    return( 0 );
}

#endif /* !MBEDTLS_SHA1_PROCESS_ALT */

/**
 * \brief          This function feeds an input buffer into an ongoing SHA-1
 *                 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context. This must be initialized
 *                 and have a hash operation started.
 * \param input    The buffer holding the input data.
 *                 This must be a readable buffer of length \p ilen Bytes.
 * \param ilen     The length of the input data \p input in Bytes.
 *
 * \return         \c 0 on success.
 * \return         A negative error code on failure.
 */
int mbedtls_sha1_update_ret( mbedtls_sha1_context *ctx,
                             const unsigned char *input,
                             size_t ilen )
{
    int ret = MBEDTLS_ERR_THIS_CORRUPTION;
    uint32_t left;
    size_t n, fill;

    SHA1_VALIDATE_RET( ctx != NULL );
    SHA1_VALIDATE_RET( ilen == 0 || input != NULL );

    if( ilen == 0 )
        return( 0 );

    left = ctx->total[0] & 0x3F;
    fill = 64 - left;

    ctx->total[0] += (uint32_t) ilen;
    ctx->total[0] &= 0xFFFFFFFF;

    if( ctx->total[0] < (uint32_t) ilen )
        ctx->total[1]++;

    if( left && ilen >= fill )
    {
        memcpy( (void *) (ctx->buffer + left), input, fill );
        if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
            return( ret );
        input += fill;
        ilen  -= fill;
        left = 0;
    }

    if( ilen >= 64 )
    {
        if( ( !IsTiny() || X86_NEED(SHA) ) && X86_HAVE( SHA ) )
        {
            if( IsAsan() )
                __asan_verify( input, ilen );
            sha1_transform_ni( ctx->state, input, ilen / 64 );
            input += ROUNDDOWN( ilen, 64 );
            ilen  -= ROUNDDOWN( ilen, 64 );
        }
        else if( !IsTiny() &&
                 X86_HAVE( BMI  ) &&
                 X86_HAVE( BMI2 ) &&
                 X86_HAVE( AVX2 ) )
        {
            if( IsAsan() )
                __asan_verify( input, ilen );
            sha1_transform_avx2( ctx->state, input, ilen / 64 );
            input += ROUNDDOWN( ilen, 64 );
            ilen  -= ROUNDDOWN( ilen, 64 );
        }
        else
        {
            do
            {
                if(( ret = mbedtls_internal_sha1_process( ctx, input ) ))
                    return( ret );
                input += 64;
                ilen  -= 64;
            }
            while( ilen >= 64 );
        }
    }

    if( ilen > 0 )
        memcpy( (void *) (ctx->buffer + left), input, ilen );

    return( 0 );
}

/**
 * \brief          This function finishes the SHA-1 operation, and writes
 *                 the result to the output buffer.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to use. This must be initialized and
 *                 have a hash operation started.
 * \param output   The SHA-1 checksum result. This must be a writable
 *                 buffer of length \c 20 Bytes.
 *
 * \return         \c 0 on success.
 * \return         A negative error code on failure.
 */
int mbedtls_sha1_finish_ret( mbedtls_sha1_context *ctx,
                             unsigned char output[20] )
{
    int ret = MBEDTLS_ERR_THIS_CORRUPTION;
    uint32_t used;
    uint32_t high, low;

    SHA1_VALIDATE_RET( ctx != NULL );
    SHA1_VALIDATE_RET( (unsigned char *)output != NULL );

    /*
     * Add padding: 0x80 then 0x00 until 8 bytes remain for the length
     */
    used = ctx->total[0] & 0x3F;

    ctx->buffer[used++] = 0x80;

    if( used <= 56 )
    {
        /* Enough room for padding + length in current block */
        mbedtls_platform_zeroize( ctx->buffer + used, 56 - used );
    }
    else
    {
        /* We'll need an extra block */
        mbedtls_platform_zeroize( ctx->buffer + used, 64 - used );
        if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
            return( ret );
        mbedtls_platform_zeroize( ctx->buffer, 56 );
    }

    /*
     * Add message length
     */
    high = ( ctx->total[0] >> 29 )
         | ( ctx->total[1] <<  3 );
    low  = ( ctx->total[0] <<  3 );

    PUT_UINT32_BE( high, ctx->buffer, 56 );
    PUT_UINT32_BE( low,  ctx->buffer, 60 );

    if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
        return( ret );

    /*
     * Output final state
     */
    PUT_UINT32_BE( ctx->state[0], output,  0 );
    PUT_UINT32_BE( ctx->state[1], output,  4 );
    PUT_UINT32_BE( ctx->state[2], output,  8 );
    PUT_UINT32_BE( ctx->state[3], output, 12 );
    PUT_UINT32_BE( ctx->state[4], output, 16 );

    return( 0 );
}

/**
 * \brief          This function calculates the SHA-1 checksum of a buffer.
 *
 *                 The function allocates the context, performs the
 *                 calculation, and frees the context.
 *
 *                 The SHA-1 result is calculated as
 *                 output = SHA-1(input buffer).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param input    The buffer holding the input data.
 *                 This must be a readable buffer of length \p ilen Bytes.
 * \param ilen     The length of the input data \p input in Bytes.
 * \param output   The SHA-1 checksum result.
 *                 This must be a writable buffer of length \c 20 Bytes.
 *
 * \return         \c 0 on success.
 * \return         A negative error code on failure.
 *
 */
int mbedtls_sha1_ret( const void *input,
                      size_t ilen,
                      unsigned char output[20] )
{
    int ret = MBEDTLS_ERR_THIS_CORRUPTION;
    mbedtls_sha1_context ctx;
    SHA1_VALIDATE_RET( ilen == 0 || input != NULL );
    SHA1_VALIDATE_RET( (unsigned char *)output != NULL );
    mbedtls_sha1_init( &ctx );
    if( ( ret = mbedtls_sha1_starts_ret( &ctx ) ) != 0 )
        goto exit;
    if( ( ret = mbedtls_sha1_update_ret( &ctx, input, ilen ) ) != 0 )
        goto exit;
    if( ( ret = mbedtls_sha1_finish_ret( &ctx, output ) ) != 0 )
        goto exit;
exit:
    mbedtls_sha1_free( &ctx );
    return( ret );
}

const mbedtls_md_info_t mbedtls_sha1_info = {
    "SHA1",
    MBEDTLS_MD_SHA1,
    20,
    64,
    (void *)mbedtls_sha1_starts_ret,
    (void *)mbedtls_sha1_update_ret,
    (void *)mbedtls_internal_sha1_process,
    (void *)mbedtls_sha1_finish_ret,
    (void *)mbedtls_sha1_ret,
};
