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Challenge | 2020 | XCTF高校网络安全专题挑战赛 | 鲲鹏计算专场 | RealWorld | hash

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题目描述

题目考点

解题思路

本题与 AES 相似, 需要利用 CPU 上 SHA2 指令集扩展. 并且同时需要使用 OpenMP 进行并行, 充分利用服务器上 48 个核心.

一个简单的实例hash.c.

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#if defined(__arm__) || defined(__aarch32__) || defined(__arm64__) || defined(__aarch64__) || defined(_M_ARM)
# if defined(__GNUC__)
#  include <stdint.h>
# endif
# if defined(__ARM_NEON) || defined(_MSC_VER) || defined(__GNUC__)
#  include <arm_neon.h>
# endif
/* GCC and LLVM Clang, but not Apple Clang */
# if defined(__GNUC__) && !defined(__apple_build_version__)
#  if defined(__ARM_ACLE) || defined(__ARM_FEATURE_CRYPTO)
#   include <arm_acle.h>
#  endif
# endif
#endif  /* ARM Headers */

static const uint32_t K[] =
{
    0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5,
    0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5,
    0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3,
    0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174,
    0xE49B69C1, 0xEFBE4786, 0x0FC19DC6, 0x240CA1CC,
    0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA,
    0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7,
    0xC6E00BF3, 0xD5A79147, 0x06CA6351, 0x14292967,
    0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13,
    0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85,
    0xA2BFE8A1, 0xA81A664B, 0xC24B8B70, 0xC76C51A3,
    0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070,
    0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5,
    0x391C0CB3, 0x4ED8AA4A, 0x5B9CCA4F, 0x682E6FF3,
    0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208,
    0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2,
};

/* Process multiple blocks. The caller is responsible for setting the initial */
/*  state, and the caller is responsible for padding the final block.        */
void sha256_process_arm(uint32_t state[8], const uint8_t data[], uint32_t length)
{
    uint32x4_t STATE0, STATE1, ABEF_SAVE, CDGH_SAVE;
    uint32x4_t MSG0, MSG1, MSG2, MSG3;
    uint32x4_t TMP0, TMP1, TMP2;

    /* Load state */
    STATE0 = vld1q_u32(&state[0]);
    STATE1 = vld1q_u32(&state[4]);

    while (length >= 64)
    {
        /* Save state */
        ABEF_SAVE = STATE0;
        CDGH_SAVE = STATE1;

        /* Load message */
        MSG0 = vld1q_u32((const uint32_t *)(data +  0));
        MSG1 = vld1q_u32((const uint32_t *)(data + 16));
        MSG2 = vld1q_u32((const uint32_t *)(data + 32));
        MSG3 = vld1q_u32((const uint32_t *)(data + 48));

        /* Reverse for little endian */
        MSG0 = vreinterpretq_u32_u8(vrev32q_u8(vreinterpretq_u8_u32(MSG0)));
        MSG1 = vreinterpretq_u32_u8(vrev32q_u8(vreinterpretq_u8_u32(MSG1)));
        MSG2 = vreinterpretq_u32_u8(vrev32q_u8(vreinterpretq_u8_u32(MSG2)));
        MSG3 = vreinterpretq_u32_u8(vrev32q_u8(vreinterpretq_u8_u32(MSG3)));

        TMP0 = vaddq_u32(MSG0, vld1q_u32(&K[0x00]));

        /* Rounds 0-3 */
        MSG0 = vsha256su0q_u32(MSG0, MSG1);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG1, vld1q_u32(&K[0x04]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG0 = vsha256su1q_u32(MSG0, MSG2, MSG3);

        /* Rounds 4-7 */
        MSG1 = vsha256su0q_u32(MSG1, MSG2);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG2, vld1q_u32(&K[0x08]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG1 = vsha256su1q_u32(MSG1, MSG3, MSG0);

        /* Rounds 8-11 */
        MSG2 = vsha256su0q_u32(MSG2, MSG3);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG3, vld1q_u32(&K[0x0c]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG2 = vsha256su1q_u32(MSG2, MSG0, MSG1);

        /* Rounds 12-15 */
        MSG3 = vsha256su0q_u32(MSG3, MSG0);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG0, vld1q_u32(&K[0x10]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG3 = vsha256su1q_u32(MSG3, MSG1, MSG2);

        /* Rounds 16-19 */
        MSG0 = vsha256su0q_u32(MSG0, MSG1);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG1, vld1q_u32(&K[0x14]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG0 = vsha256su1q_u32(MSG0, MSG2, MSG3);

        /* Rounds 20-23 */
        MSG1 = vsha256su0q_u32(MSG1, MSG2);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG2, vld1q_u32(&K[0x18]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG1 = vsha256su1q_u32(MSG1, MSG3, MSG0);

        /* Rounds 24-27 */
        MSG2 = vsha256su0q_u32(MSG2, MSG3);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG3, vld1q_u32(&K[0x1c]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG2 = vsha256su1q_u32(MSG2, MSG0, MSG1);

        /* Rounds 28-31 */
        MSG3 = vsha256su0q_u32(MSG3, MSG0);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG0, vld1q_u32(&K[0x20]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG3 = vsha256su1q_u32(MSG3, MSG1, MSG2);

        /* Rounds 32-35 */
        MSG0 = vsha256su0q_u32(MSG0, MSG1);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG1, vld1q_u32(&K[0x24]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG0 = vsha256su1q_u32(MSG0, MSG2, MSG3);

        /* Rounds 36-39 */
        MSG1 = vsha256su0q_u32(MSG1, MSG2);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG2, vld1q_u32(&K[0x28]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG1 = vsha256su1q_u32(MSG1, MSG3, MSG0);

        /* Rounds 40-43 */
        MSG2 = vsha256su0q_u32(MSG2, MSG3);
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG3, vld1q_u32(&K[0x2c]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);
        MSG2 = vsha256su1q_u32(MSG2, MSG0, MSG1);

        /* Rounds 44-47 */
        MSG3 = vsha256su0q_u32(MSG3, MSG0);
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG0, vld1q_u32(&K[0x30]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);
        MSG3 = vsha256su1q_u32(MSG3, MSG1, MSG2);

        /* Rounds 48-51 */
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG1, vld1q_u32(&K[0x34]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);

        /* Rounds 52-55 */
        TMP2 = STATE0;
        TMP0 = vaddq_u32(MSG2, vld1q_u32(&K[0x38]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);

        /* Rounds 56-59 */
        TMP2 = STATE0;
        TMP1 = vaddq_u32(MSG3, vld1q_u32(&K[0x3c]));
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP0);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP0);

        /* Rounds 60-63 */
        TMP2 = STATE0;
        STATE0 = vsha256hq_u32(STATE0, STATE1, TMP1);
        STATE1 = vsha256h2q_u32(STATE1, TMP2, TMP1);

        /* Combine state */
        STATE0 = vaddq_u32(STATE0, ABEF_SAVE);
        STATE1 = vaddq_u32(STATE1, CDGH_SAVE);

        data += 64;
        length -= 64;
    }

    /* Save state */
    vst1q_u32(&state[0], STATE0);
    vst1q_u32(&state[4], STATE1);
}

#if defined(TEST_MAIN)

#include <stdio.h>
#include <string.h>
int main(int argc, char* argv[])
{
    /* empty message with padding */
    uint8_t message[64];
    memset(message, 0x00, sizeof(message));
    message[0] = 0x80;

    /* initial state */
    uint32_t state[8] = {
        0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
        0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
    };

    sha256_process_arm(state, message, sizeof(message));

    const uint8_t b1 = (uint8_t)(state[0] >> 24);
    const uint8_t b2 = (uint8_t)(state[0] >> 16);
    const uint8_t b3 = (uint8_t)(state[0] >>  8);
    const uint8_t b4 = (uint8_t)(state[0] >>  0);
    const uint8_t b5 = (uint8_t)(state[1] >> 24);
    const uint8_t b6 = (uint8_t)(state[1] >> 16);
    const uint8_t b7 = (uint8_t)(state[1] >>  8);
    const uint8_t b8 = (uint8_t)(state[1] >>  0);

    /* e3b0c44298fc1c14... */
    printf("SHA256 hash of empty message: ");
    printf("%02X%02X%02X%02X%02X%02X%02X%02X...\n",
        b1, b2, b3, b4, b5, b6, b7, b8);

    int success = ((b1 == 0xE3) && (b2 == 0xB0) && (b3 == 0xC4) && (b4 == 0x42) &&
                    (b5 == 0x98) && (b6 == 0xFC) && (b7 == 0x1C) && (b8 == 0x14));

    if (success)
        printf("Success!\n");
    else
        printf("Failure!\n");

    return (success != 0 ? 0 : 1);
}

#endif