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+--- Thread: is there some thing wrong in KERNEL_FQ void m22400_init (KERN_ATTR_TMPS_ESALT (aescry (/thread-10404.html)
is there some thing wrong in KERNEL_FQ void m22400_init (KERN_ATTR_TMPS_ESALT (aescry - hellohihi - 10-17-2021
in KERNEL_FQ void m22400_init (KERN_ATTR_TMPS_ESALT (aescrypt_tmp_t, aescrypt_t)), I believe the following code is wrong.
......
u32 w[80] = { 0 };
for (u32 i = 0, j = 0; i < pw_len; i += 4, j += 1)
{
w[j] = hc_swap32_S (pws[gid].i[j]);
}
// sha256:
sha256_ctx_t ctx;
sha256_init (&ctx);
sha256_update (&ctx, s, 32);
sha256_update (&ctx, w, pw_len);
sha256_final (&ctx);
// set tmps:
#ifdef _unroll
#pragma unroll
#endif
for (int i = 127; i >= 0; i--) // create some space for the first digest without extra buffer
{
w[8 + i] = w[i];
}
w[0] = ctx.h[0];
w[1] = ctx.h[1];
w[2] = ctx.h[2];
w[3] = ctx.h[3];
w[4] = ctx.h[4];
w[5] = ctx.h[5];
w[6] = ctx.h[6];
w[7] = ctx.h[7];
.....
The w size is 80, but for w[8 + i] = w[i] the i start from 127, this means i is out of the boundary.
RE: is there some thing wrong in KERNEL_FQ void m22400_init (KERN_ATTR_TMPS_ESALT (aescry - philsmd - 10-22-2021
nice find, it really seems so that this commit https://github.com/hashcat/hashcat/commit/0a60805 did change more than just the way we do the "utf16 encoding". The buffer sizes were changed; and you are right it seems that buffers do overflow with the new code. We should ask atom/jsteube if it's enough to just keep the old/correct buffer size also for the updated utf16 encoding.
The original code seems to not have this problem (i.e. any version of the -m 22400 hash module before the urf16 encoding change).
Please open a new issue on github https://github.com/hashcat/hashcat/issues and mention these details (your observation about the buffer overflow and which commit seem to have broken it). Thx
RE: is there some thing wrong in KERNEL_FQ void m22400_init (KERN_ATTR_TMPS_ESALT (aescry - atom - 10-22-2021
Problem was fixed with commit https://github.com/hashcat/hashcat/commit/139ace28a90472af915dc862bb3b05fc9054a5a8 thanks for reporting. Indeed nice find!
Keeping the buffer size is fine, the UTF16 conversion is done inside the new gpu_utf8_to_utf16() kernel.