/*
 *  RFC 1321 compliant MD5 implementation
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: GPL-2.0
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
/*
 *  The MD5 algorithm was designed by Ron Rivest in 1991.
 *
 *  http://www.ietf.org/rfc/rfc1321.txt
 */

#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif

#if defined(MBEDTLS_MD5_C)

#include "mbedtls/md5.h"
#include "mbedtls/platform_util.h"

#include <string.h>

#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_C */
#endif /* MBEDTLS_SELF_TEST */

#if !defined(MBEDTLS_MD5_ALT)

/*
 * 32-bit integer manipulation macros (little endian)
 */
#ifndef GET_UINT32_LE
#define GET_UINT32_LE(n,b,i)                            \
    {                                                       \
        (n) = ( (uint32_t) (b)[(i)    ]       )             \
              | ( (uint32_t) (b)[(i) + 1] <<  8 )             \
              | ( (uint32_t) (b)[(i) + 2] << 16 )             \
              | ( (uint32_t) (b)[(i) + 3] << 24 );            \
    }
#endif

#ifndef PUT_UINT32_LE
#define PUT_UINT32_LE(n,b,i)                                    \
    {                                                               \
        (b)[(i)    ] = (unsigned char) ( ( (n)       ) & 0xFF );    \
        (b)[(i) + 1] = (unsigned char) ( ( (n) >>  8 ) & 0xFF );    \
        (b)[(i) + 2] = (unsigned char) ( ( (n) >> 16 ) & 0xFF );    \
        (b)[(i) + 3] = (unsigned char) ( ( (n) >> 24 ) & 0xFF );    \
    }
#endif

void mbedtls_md5_init(mbedtls_md5_context *ctx) {
    memset(ctx, 0, sizeof(mbedtls_md5_context));
}

void mbedtls_md5_free(mbedtls_md5_context *ctx) {
    if (ctx == NULL)
        return;

    mbedtls_platform_zeroize(ctx, sizeof(mbedtls_md5_context));
}

void mbedtls_md5_clone(mbedtls_md5_context *dst,
                       const mbedtls_md5_context *src) {
    *dst = *src;
}

/*
 * MD5 context setup
 */
int mbedtls_md5_starts_ret(mbedtls_md5_context *ctx) {
    ctx->total[0] = 0;
    ctx->total[1] = 0;

    ctx->state[0] = 0x67452301;
    ctx->state[1] = 0xEFCDAB89;
    ctx->state[2] = 0x98BADCFE;
    ctx->state[3] = 0x10325476;

    return (0);
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_md5_starts(mbedtls_md5_context *ctx) {
    mbedtls_md5_starts_ret(ctx);
}
#endif

#if !defined(MBEDTLS_MD5_PROCESS_ALT)
int mbedtls_internal_md5_process(mbedtls_md5_context *ctx,
                                 const unsigned char data[64]) {
    uint32_t X[16], A, B, C, D;

    GET_UINT32_LE(X[ 0], data,  0);
    GET_UINT32_LE(X[ 1], data,  4);
    GET_UINT32_LE(X[ 2], data,  8);
    GET_UINT32_LE(X[ 3], data, 12);
    GET_UINT32_LE(X[ 4], data, 16);
    GET_UINT32_LE(X[ 5], data, 20);
    GET_UINT32_LE(X[ 6], data, 24);
    GET_UINT32_LE(X[ 7], data, 28);
    GET_UINT32_LE(X[ 8], data, 32);
    GET_UINT32_LE(X[ 9], data, 36);
    GET_UINT32_LE(X[10], data, 40);
    GET_UINT32_LE(X[11], data, 44);
    GET_UINT32_LE(X[12], data, 48);
    GET_UINT32_LE(X[13], data, 52);
    GET_UINT32_LE(X[14], data, 56);
    GET_UINT32_LE(X[15], data, 60);

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

#define P(a,b,c,d,k,s,t)                                \
    {                                                       \
        a += F(b,c,d) + X[k] + t; a = S(a,s) + b;           \
    }

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

#define F(x,y,z) (z ^ (x & (y ^ z)))

    P(A, B, C, D,  0,  7, 0xD76AA478);
    P(D, A, B, C,  1, 12, 0xE8C7B756);
    P(C, D, A, B,  2, 17, 0x242070DB);
    P(B, C, D, A,  3, 22, 0xC1BDCEEE);
    P(A, B, C, D,  4,  7, 0xF57C0FAF);
    P(D, A, B, C,  5, 12, 0x4787C62A);
    P(C, D, A, B,  6, 17, 0xA8304613);
    P(B, C, D, A,  7, 22, 0xFD469501);
    P(A, B, C, D,  8,  7, 0x698098D8);
    P(D, A, B, C,  9, 12, 0x8B44F7AF);
    P(C, D, A, B, 10, 17, 0xFFFF5BB1);
    P(B, C, D, A, 11, 22, 0x895CD7BE);
    P(A, B, C, D, 12,  7, 0x6B901122);
    P(D, A, B, C, 13, 12, 0xFD987193);
    P(C, D, A, B, 14, 17, 0xA679438E);
    P(B, C, D, A, 15, 22, 0x49B40821);

#undef F

#define F(x,y,z) (y ^ (z & (x ^ y)))

    P(A, B, C, D,  1,  5, 0xF61E2562);
    P(D, A, B, C,  6,  9, 0xC040B340);
    P(C, D, A, B, 11, 14, 0x265E5A51);
    P(B, C, D, A,  0, 20, 0xE9B6C7AA);
    P(A, B, C, D,  5,  5, 0xD62F105D);
    P(D, A, B, C, 10,  9, 0x02441453);
    P(C, D, A, B, 15, 14, 0xD8A1E681);
    P(B, C, D, A,  4, 20, 0xE7D3FBC8);
    P(A, B, C, D,  9,  5, 0x21E1CDE6);
    P(D, A, B, C, 14,  9, 0xC33707D6);
    P(C, D, A, B,  3, 14, 0xF4D50D87);
    P(B, C, D, A,  8, 20, 0x455A14ED);
    P(A, B, C, D, 13,  5, 0xA9E3E905);
    P(D, A, B, C,  2,  9, 0xFCEFA3F8);
    P(C, D, A, B,  7, 14, 0x676F02D9);
    P(B, C, D, A, 12, 20, 0x8D2A4C8A);

#undef F

#define F(x,y,z) (x ^ y ^ z)

    P(A, B, C, D,  5,  4, 0xFFFA3942);
    P(D, A, B, C,  8, 11, 0x8771F681);
    P(C, D, A, B, 11, 16, 0x6D9D6122);
    P(B, C, D, A, 14, 23, 0xFDE5380C);
    P(A, B, C, D,  1,  4, 0xA4BEEA44);
    P(D, A, B, C,  4, 11, 0x4BDECFA9);
    P(C, D, A, B,  7, 16, 0xF6BB4B60);
    P(B, C, D, A, 10, 23, 0xBEBFBC70);
    P(A, B, C, D, 13,  4, 0x289B7EC6);
    P(D, A, B, C,  0, 11, 0xEAA127FA);
    P(C, D, A, B,  3, 16, 0xD4EF3085);
    P(B, C, D, A,  6, 23, 0x04881D05);
    P(A, B, C, D,  9,  4, 0xD9D4D039);
    P(D, A, B, C, 12, 11, 0xE6DB99E5);
    P(C, D, A, B, 15, 16, 0x1FA27CF8);
    P(B, C, D, A,  2, 23, 0xC4AC5665);

#undef F

#define F(x,y,z) (y ^ (x | ~z))

    P(A, B, C, D,  0,  6, 0xF4292244);
    P(D, A, B, C,  7, 10, 0x432AFF97);
    P(C, D, A, B, 14, 15, 0xAB9423A7);
    P(B, C, D, A,  5, 21, 0xFC93A039);
    P(A, B, C, D, 12,  6, 0x655B59C3);
    P(D, A, B, C,  3, 10, 0x8F0CCC92);
    P(C, D, A, B, 10, 15, 0xFFEFF47D);
    P(B, C, D, A,  1, 21, 0x85845DD1);
    P(A, B, C, D,  8,  6, 0x6FA87E4F);
    P(D, A, B, C, 15, 10, 0xFE2CE6E0);
    P(C, D, A, B,  6, 15, 0xA3014314);
    P(B, C, D, A, 13, 21, 0x4E0811A1);
    P(A, B, C, D,  4,  6, 0xF7537E82);
    P(D, A, B, C, 11, 10, 0xBD3AF235);
    P(C, D, A, B,  2, 15, 0x2AD7D2BB);
    P(B, C, D, A,  9, 21, 0xEB86D391);

#undef F

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

    return (0);
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_md5_process(mbedtls_md5_context *ctx,
                         const unsigned char data[64]) {
    mbedtls_internal_md5_process(ctx, data);
}
#endif
#endif /* !MBEDTLS_MD5_PROCESS_ALT */

/*
 * MD5 process buffer
 */
int mbedtls_md5_update_ret(mbedtls_md5_context *ctx,
                           const unsigned char *input,
                           size_t ilen) {
    int ret;
    size_t fill;
    uint32_t left;

    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_md5_process(ctx, ctx->buffer)) != 0)
            return (ret);

        input += fill;
        ilen  -= fill;
        left = 0;
    }

    while (ilen >= 64) {
        if ((ret = mbedtls_internal_md5_process(ctx, input)) != 0)
            return (ret);

        input += 64;
        ilen  -= 64;
    }

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

    return (0);
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_md5_update(mbedtls_md5_context *ctx,
                        const unsigned char *input,
                        size_t ilen) {
    mbedtls_md5_update_ret(ctx, input, ilen);
}
#endif

/*
 * MD5 final digest
 */
int mbedtls_md5_finish_ret(mbedtls_md5_context *ctx,
                           unsigned char output[16]) {
    int ret;
    uint32_t used;
    uint32_t high, low;

    /*
     * 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 */
        memset(ctx->buffer + used, 0, 56 - used);
    } else {
        /* We'll need an extra block */
        memset(ctx->buffer + used, 0, 64 - used);

        if ((ret = mbedtls_internal_md5_process(ctx, ctx->buffer)) != 0)
            return (ret);

        memset(ctx->buffer, 0, 56);
    }

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

    PUT_UINT32_LE(low,  ctx->buffer, 56);
    PUT_UINT32_LE(high, ctx->buffer, 60);

    if ((ret = mbedtls_internal_md5_process(ctx, ctx->buffer)) != 0)
        return (ret);

    /*
     * Output final state
     */
    PUT_UINT32_LE(ctx->state[0], output,  0);
    PUT_UINT32_LE(ctx->state[1], output,  4);
    PUT_UINT32_LE(ctx->state[2], output,  8);
    PUT_UINT32_LE(ctx->state[3], output, 12);

    return (0);
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_md5_finish(mbedtls_md5_context *ctx,
                        unsigned char output[16]) {
    mbedtls_md5_finish_ret(ctx, output);
}
#endif

#endif /* !MBEDTLS_MD5_ALT */

/*
 * output = MD5( input buffer )
 */
int mbedtls_md5_ret(const unsigned char *input,
                    size_t ilen,
                    unsigned char output[16]) {
    int ret;
    mbedtls_md5_context ctx;

    mbedtls_md5_init(&ctx);

    if ((ret = mbedtls_md5_starts_ret(&ctx)) != 0)
        goto exit;

    if ((ret = mbedtls_md5_update_ret(&ctx, input, ilen)) != 0)
        goto exit;

    if ((ret = mbedtls_md5_finish_ret(&ctx, output)) != 0)
        goto exit;

exit:
    mbedtls_md5_free(&ctx);

    return (ret);
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_md5(const unsigned char *input,
                 size_t ilen,
                 unsigned char output[16]) {
    mbedtls_md5_ret(input, ilen, output);
}
#endif

#if defined(MBEDTLS_SELF_TEST)
/*
 * RFC 1321 test vectors
 */
static const unsigned char md5_test_buf[7][81] = {
    { "" },
    { "a" },
    { "abc" },
    { "message digest" },
    { "abcdefghijklmnopqrstuvwxyz" },
    { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
    {
        "12345678901234567890123456789012345678901234567890123456789012"
        "345678901234567890"
    }
};

static const size_t md5_test_buflen[7] = {
    0, 1, 3, 14, 26, 62, 80
};

static const unsigned char md5_test_sum[7][16] = {
    {
        0xD4, 0x1D, 0x8C, 0xD9, 0x8F, 0x00, 0xB2, 0x04,
        0xE9, 0x80, 0x09, 0x98, 0xEC, 0xF8, 0x42, 0x7E
    },
    {
        0x0C, 0xC1, 0x75, 0xB9, 0xC0, 0xF1, 0xB6, 0xA8,
        0x31, 0xC3, 0x99, 0xE2, 0x69, 0x77, 0x26, 0x61
    },
    {
        0x90, 0x01, 0x50, 0x98, 0x3C, 0xD2, 0x4F, 0xB0,
        0xD6, 0x96, 0x3F, 0x7D, 0x28, 0xE1, 0x7F, 0x72
    },
    {
        0xF9, 0x6B, 0x69, 0x7D, 0x7C, 0xB7, 0x93, 0x8D,
        0x52, 0x5A, 0x2F, 0x31, 0xAA, 0xF1, 0x61, 0xD0
    },
    {
        0xC3, 0xFC, 0xD3, 0xD7, 0x61, 0x92, 0xE4, 0x00,
        0x7D, 0xFB, 0x49, 0x6C, 0xCA, 0x67, 0xE1, 0x3B
    },
    {
        0xD1, 0x74, 0xAB, 0x98, 0xD2, 0x77, 0xD9, 0xF5,
        0xA5, 0x61, 0x1C, 0x2C, 0x9F, 0x41, 0x9D, 0x9F
    },
    {
        0x57, 0xED, 0xF4, 0xA2, 0x2B, 0xE3, 0xC9, 0x55,
        0xAC, 0x49, 0xDA, 0x2E, 0x21, 0x07, 0xB6, 0x7A
    }
};

/*
 * Checkup routine
 */
int mbedtls_md5_self_test(int verbose) {
    int i, ret = 0;
    unsigned char md5sum[16];

    for (i = 0; i < 7; i++) {
        if (verbose != 0)
            mbedtls_printf("  MD5 test #%d: ", i + 1);

        ret = mbedtls_md5_ret(md5_test_buf[i], md5_test_buflen[i], md5sum);
        if (ret != 0)
            goto fail;

        if (memcmp(md5sum, md5_test_sum[i], 16) != 0) {
            ret = 1;
            goto fail;
        }

        if (verbose != 0)
            mbedtls_printf("passed\n");
    }

    if (verbose != 0)
        mbedtls_printf("\n");

    return (0);

fail:
    if (verbose != 0)
        mbedtls_printf("failed\n");

    return (ret);
}

#endif /* MBEDTLS_SELF_TEST */

#endif /* MBEDTLS_MD5_C */