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Full Version: Creating sha512(sha512($pass).$salt) kernel
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Hey everyone, lately I've been trying to make sha512(sha512($pass).$salt) kernel, although I keep failing. I believe it's because I don't really understand u64 in which sha512 is stored.

I've tried doing it in few different ways but none of them seemed to work, I would very appreciate any hint of what I'm doing wrong or what I'm missing. Cheers!

Here is the code taken from the loop

Code:
/**
  * loop
  */

  for (u32 il_pos = 0; il_pos < il_cnt; il_pos++)
  {
    pw_t tmp = PASTE_PW;

    tmp.pw_len = apply_rules (rules_buf[il_pos].cmds, tmp.i, tmp.pw_len);

    sha512_ctx_t ctx0;

    sha512_init (&ctx0);

    sha512_update_swap (&ctx0, tmp.i, tmp.pw_len);

    sha512_final (&ctx0);

    //sha512($pass)

    const u32 ah = h32_from_64_S (ctx0.h[0]);
    const u32 al = l32_from_64_S (ctx0.h[0]);
    const u32 bh = h32_from_64_S (ctx0.h[1]);
    const u32 bl = l32_from_64_S (ctx0.h[1]);
    const u32 ch = h32_from_64_S (ctx0.h[2]);
    const u32 cl = l32_from_64_S (ctx0.h[2]);
    const u32 dh = h32_from_64_S (ctx0.h[3]);
    const u32 dl = l32_from_64_S (ctx0.h[3]);
    const u32 eh = h32_from_64_S (ctx0.h[4]);
    const u32 el = l32_from_64_S (ctx0.h[4]);
    const u32 fh = h32_from_64_S (ctx0.h[5]);
    const u32 fl = l32_from_64_S (ctx0.h[5]);
    const u32 gh = h32_from_64_S (ctx0.h[6]);
    const u32 gl = l32_from_64_S (ctx0.h[6]);
    const u32 hh = h32_from_64_S (ctx0.h[7]);
    const u32 hl = l32_from_64_S (ctx0.h[7]);

    //converting to u32 from u64 in order to convert bin to hex below

    sha512_ctx_t ctx;

    sha512_init (&ctx);

    ctx.w0[0] = uint_to_hex_lower8_le ((ah >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((ah >> 24) & 255) << 16;
    ctx.w0[1] = uint_to_hex_lower8_le ((ah >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((ah >>  8) & 255) << 16;
    ctx.w0[2] = uint_to_hex_lower8_le ((al >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((al >> 24) & 255) << 16;
    ctx.w0[3] = uint_to_hex_lower8_le ((al >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((al >>  8) & 255) << 16;
    ctx.w1[0] = uint_to_hex_lower8_le ((bh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((bh >> 24) & 255) << 16;
    ctx.w1[1] = uint_to_hex_lower8_le ((bh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((bh >>  8) & 255) << 16;
    ctx.w1[2] = uint_to_hex_lower8_le ((bl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((bl >> 24) & 255) << 16;
    ctx.w1[3] = uint_to_hex_lower8_le ((bl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((bl >>  8) & 255) << 16;
    ctx.w2[0] = uint_to_hex_lower8_le ((ch >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((ch >> 24) & 255) << 16;
    ctx.w2[1] = uint_to_hex_lower8_le ((ch >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((ch >>  8) & 255) << 16;
    ctx.w2[2] = uint_to_hex_lower8_le ((cl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((cl >> 24) & 255) << 16;
    ctx.w2[3] = uint_to_hex_lower8_le ((cl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((cl >>  8) & 255) << 16;
    ctx.w3[0] = uint_to_hex_lower8_le ((dh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((dh >> 24) & 255) << 16;
    ctx.w3[1] = uint_to_hex_lower8_le ((dh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((dh >>  8) & 255) << 16;
    ctx.w3[2] = uint_to_hex_lower8_le ((dl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((dl >> 24) & 255) << 16;
    ctx.w3[3] = uint_to_hex_lower8_le ((dl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((dl >>  8) & 255) << 16;
    ctx.w4[0] = uint_to_hex_lower8_le ((eh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((eh >> 24) & 255) << 16;
    ctx.w4[1] = uint_to_hex_lower8_le ((eh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((eh >>  8) & 255) << 16;
    ctx.w4[2] = uint_to_hex_lower8_le ((el >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((el >> 24) & 255) << 16;
    ctx.w4[3] = uint_to_hex_lower8_le ((el >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((el >>  8) & 255) << 16;
    ctx.w5[0] = uint_to_hex_lower8_le ((fh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((fh >> 24) & 255) << 16;
    ctx.w5[1] = uint_to_hex_lower8_le ((fh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((fh >>  8) & 255) << 16;
    ctx.w5[2] = uint_to_hex_lower8_le ((fl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((fl >> 24) & 255) << 16;
    ctx.w5[3] = uint_to_hex_lower8_le ((fl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((fl >>  8) & 255) << 16;
    ctx.w6[0] = uint_to_hex_lower8_le ((gh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((gh >> 24) & 255) << 16;
    ctx.w6[1] = uint_to_hex_lower8_le ((gh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((gh >>  8) & 255) << 16;
    ctx.w6[2] = uint_to_hex_lower8_le ((gl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((gl >> 24) & 255) << 16;
    ctx.w6[3] = uint_to_hex_lower8_le ((gl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((gl >>  8) & 255) << 16;
    ctx.w7[0] = uint_to_hex_lower8_le ((hh >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((hh >> 24) & 255) << 16;
    ctx.w7[1] = uint_to_hex_lower8_le ((hh >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((hh >>  8) & 255) << 16;
    ctx.w7[2] = uint_to_hex_lower8_le ((hl >> 16) & 255) <<  0 | uint_to_hex_lower8_le ((hl >> 24) & 255) << 16;
    ctx.w7[3] = uint_to_hex_lower8_le ((hl >>  0) & 255) <<  0 | uint_to_hex_lower8_le ((hl >>  8) & 255) << 16;

    //at this point, from what I understand I should have sha512($pass) in hex

    //and this part - making sha512(sha512($pass)) is where I believe I got something wrong I've tried doing it in three different ways (really just trial and error)

    // first attempt:
    // sha512_transform (ctx.w0, ctx.w1, ctx.w2, ctx.w3, ctx.w4, ctx.w5, ctx.w6, ctx.w7, ctx.h);

    // second attempt:
    // sha512_update_128 (&ctx, w0, w1, w2, w3, w4, w5, w6, w7, 128);

    // third attempt:
    // u64 final[32] = { 0 };
    // final[ 0] = hl32_to_64 (w0[0], w0[1]);
    // final[ 1] = hl32_to_64 (w0[2], w0[3]);
    // final[ 2] = hl32_to_64 (w1[0], w1[1]);
    // final[ 3] = hl32_to_64 (w1[2], w1[3]);
    // final[ 4] = hl32_to_64 (w2[0], w2[1]);
    // final[ 5] = hl32_to_64 (w2[2], w2[3]);
    // final[ 6] = hl32_to_64 (w3[0], w3[1]);
    // final[ 7] = hl32_to_64 (w3[2], w3[3]);
    // final[ 8] = hl32_to_64 (w4[0], w4[1]);
    // final[ 9] = hl32_to_64 (w4[2], w4[3]);
    // final[10] = hl32_to_64 (w5[0], w5[1]);
    // final[11] = hl32_to_64 (w5[2], w5[3]);
    // final[12] = hl32_to_64 (w6[0], w6[1]);
    // final[13] = hl32_to_64 (w6[2], w6[3]);
    // final[14] = hl32_to_64 (w7[0], w7[1]);
    // final[15] = hl32_to_64 (w7[2], w7[3]);

    sha512_update (&ctx, final, 64);

    sha512_update (&ctx, s, salt_len);

    sha512_final (&ctx);

    const u32 r0 = l32_from_64_S (ctx.h[7]);
    const u32 r1 = h32_from_64_S (ctx.h[7]);
    const u32 r2 = l32_from_64_S (ctx.h[3]);
    const u32 r3 = h32_from_64_S (ctx.h[3]);

    COMPARE_M_SCALAR (r0, r1, r2, r3);
  }
shouldn't the first hash be 128 hex characters (instead of 64) ? Just test with "echo -n hashcat | sha512sum", it is exactly 128 hex chars long.

you would also need to test if the salt needs to be swapped etc
for instance I see sha512_update_global_swap () used in the unmodified -m 1720 kernel.

The COMPARE_M_SCALAR is also suspicous ... why would you test with multiple (2+) hashes first ? use the sxx kernel function for single (1 only) hash and COMPARE_S_SCALAR to compare...

for testing you should also always make sure to remove the cached kernel folder (kernels/).

These are just a few hints, didn't look carefully at the code yet

It would make sense to use printf () for debugging/troubleshooting and maybe an (Intel) CPU with Intel OpenCL Runtime installed (it's probably the easiest to test and debug with printf ()).
Thank you very much for the answer.

The "sha512_update (&ctx, final, 64);" was supposed to be commented out as it was part of the third attempt. I understand now it was a mistake, the reason for it was me looking at 21000 - sha512(sha512_bin(pass)) kernel. However changing it into 128 didn't fix the kernel.

I didn't use sha512_update_global_swap (), because I didn't notice it being used in simillar kernels like 20710 - sha256(sha256($pass).$salt); just to make sure I've tried changing it, didn't seem to work either

It is COMPARE_M_SCALAR, because I just copied this part, the sxx fuction I got pretty much the same code so didn't thought it would be relevant.

I remember about removing cached kernel.

I will try to play around with printf (), but I gotta admit it is a bit confusing to me, and so is Intel OpenCL Runtime

Just additional info:
- I double checked that I'm running correct hash (verified plaintext) for testing
- I didn't make new kernel file, I'm editing just m01710_a0-pure.cl and running hashcat with --self-test-disable; I did it because I assumed it wouldn't matter, but perhaps I'm wrong
in OpenCL/m20710_a0-pure.cl I don't see that ctx.w0[0] is modified directly etc...

why don't you just start with 2 very easy blocks of init/update(s)/final for the first SHA512 hash and init/update(s)/final for the second SHA512 hash.

you could just use

Code:
sha512_init (&ctx2);

u32 second[32];

second[ 0] = ...
...
second[31] = ... // 32 * 4 = 128

sha512_update (&ctx2, second, 128);
sha512_update (&ctx2, salt, salt_len); // or sha512_update_swap () ?
sha512_final (&ctx2);

first rule of optimization/implementation: do not optimize! just make it work with simple/easy code... optimizations come later