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Java中重写GIMLIHI散列

hash c java

Lev Knoblock · 技术社区 · 6 年前

我正试图从C到Java重写GimLIIHHASH。

我已经对照C代码和测试向量检查了我对gimli排列的重写,这是正确的,所以问题就在我对实际哈希的重写中,尽管我不知道在哪里。

void Gimli_hash(const uint8_t *input,
                uint64_t inputByteLen,
                uint8_t *output,
                uint64_t outputByteLen)
{
    uint32_t state[12];
    uint8_t* state_8 = (uint8_t*)state;
    uint64_t blockSize = 0;
    uint64_t i;

    // === Initialize the state ===
    memset(state, 0, sizeof(state));

    // === Absorb all the input blocks ===
    while(inputByteLen > 0) {
        blockSize = MIN(inputByteLen, rateInBytes);
        for(i=0; i<blockSize; i++)
            state_8[i] ^= input[i];
        input += blockSize;
        inputByteLen -= blockSize;

        if (blockSize == rateInBytes) {
            gimli(state);
            blockSize = 0;
        }
    }

    // === Do the padding and switch to the squeezing phase ===
    state_8[blockSize] ^= 0x1F;
    // Add the second bit of padding
    state_8[rateInBytes-1] ^= 0x80;
    // Switch to the squeezing phase
    gimli(state);

    // === Squeeze out all the output blocks ===
    while(outputByteLen > 0) {
        blockSize = MIN(outputByteLen, rateInBytes);
        memcpy(output, state, blockSize);
        output += blockSize;
        outputByteLen -= blockSize;

        if (outputByteLen > 0)
            gimli(state);
    }
}

这直接取自Gimli的C实现, 下面是我已经编写的Java代码:

public static byte[] hash(byte[] input, int outputLen) {
        int inputlen = input.length;

        int[] state = new int[12];
        byte[] state_8 = stateToBytes(state);
        int blocksize = 0;
        int i;

        int pointer = 0;

        /* Absorbing input */
        while (inputlen > 0) {
            blocksize = Math.min(inputlen, rateInBytes);
            for (i = 0; Integer.compareUnsigned(i, blocksize) < 0; i++) {
                state_8[i] ^= input[i + pointer];
            }
            state = stateToInt(state_8);

            pointer += blocksize;
            inputlen -= blocksize;

            if (blocksize == rateInBytes) {
                gimli(state);
                state_8 = stateToBytes(state);
                blocksize = 0;
            }
        }

        state_8[blocksize] ^= 0x1f;
        state_8[rateInBytes - 1] ^= 0x80;
        state = stateToInt(state_8);
        gimli(state);
        state_8 = stateToBytes(state);

        byte[] output = new byte[outputLen];
        int outputPointer = 0;

        while (outputLen > 0) {
            blocksize = Math.min(outputLen, rateInBytes);
            System.arraycopy(state_8, 0, output, outputPointer, blocksize);
            outputPointer += blocksize;
            outputLen -= blocksize;

            if (outputLen > 0) {
                gimli(state);
                state_8 = stateToBytes(state);
            }
        }

        return output;
    }

StateToInt和StateToBytes只是在状态的字节格式和int格式之间进行转换(因为排列操作的是int格式,而哈希操作的是字节格式)。当对空字符串(0字节)进行散列时,C实现返回B0634 B2C0B082AEDC5A0FE4EE3ADCFC989EC05DE6F0ADB04B3AAAC27 1F67,Java代码返回4B7F6DA2D5A901DBB580A0864 7E716EA1116328 85 993DA0BA29 D88 CE8926AF025。

对Java实现与C语言的不同之处的任何帮助都将是非常值得赞赏的。

1 回复 | 直到 6 年前

Lev Knoblock 6 年前

结果表明,散列不起作用的原因是一个终结性问题: 原始StateToBytes和StateToInt不起作用,因为它位于Be而不是Le: 原件:

private static byte[] stateToBytes(int[] state) {
        byte[][] temp = new byte[state.length][];

        for (int i = 0; i < temp.length; i++) {
            temp[i] = intToBytes(state[i]);
        }

        return merge(temp);
    }

    private static int[] stateToInt(byte[] state) {
        int[] out = new int[state.length / 4];
        for (int i = 0; i < (state.length / 4); i++) {
            out[i] = byteArrayToInt(Arrays.copyOfRange(state, (i * 4), ((i + 1) * 4)));
        }

        return out;
    }

更新:

private static byte[] stateToBytes(int[] state) {
        byte[][] temp = new byte[state.length][];

        for (int i = 0; i < temp.length; i++) {
            temp[i] = reverse(intToBytes(state[i]));
        }

        return merge(temp);
    }

    private static int[] stateToInt(byte[] state) {
        int[] out = new int[state.length / 4];
        for (int i = 0; i < (state.length / 4); i++) {
            out[i] = byteArrayToInt(reverse(Arrays.copyOfRange(state, (i * 4), ((i + 1) * 4))));
        }

        return out;
    }

感谢@paddy让我注意到这些功能的行为。