[john-users] GekkoScience NEWPAC (Dual BM1387) USB Stickminer (New 2PAC)

[Powen Cheng]

Hello,

I was wondering if we can use this miner to crack hashes with JTR and
cgminer. I would think, cgminer can be repurpose and be use to solve hashes
like JTR?

https://www.419mining.com/shop/miners/gekkoscience-newpac-dual-bm1387-usb-stickminer/

Regards,
madtomic

[Solar Designer]

Post by Powen Cheng
I was wondering if we can use this miner to crack hashes with JTR and
cgminer. I would think, cgminer can be repurpose and be use to solve hashes
like JTR?

No, this sort of hardware is far too specialized and can't be repurposed
like that.

Alexander

[Powen Cheng]

Even not through the use of open source of cgminer? I would think solving
SHA256 hashes on this miner would be the same as solving hashes on JTR?

Post by Powen Cheng

Post by Powen Cheng
I was wondering if we can use this miner to crack hashes with JTR and
cgminer. I would think, cgminer can be repurpose and be use to solve

hashes

Post by Powen Cheng
like JTR?

No, this sort of hardware is far too specialized and can't be repurposed
like that.
Alexander

[Solar Designer]

Post by Powen Cheng
Even not through the use of open source of cgminer?

No.

Post by Powen Cheng
I would think solving
SHA256 hashes on this miner would be the same as solving hashes on JTR?

It isn't.

Bitcoin miners compute double-SHA-256 (not SHA-256) of block headers
(not passwords), in which they adjust the nonce field, and then compare
the result for being not greater than target (not for being equal to a
target hash). This is a sufficiently different task from what we have
in password cracking to make Bitcoin mining ASICs non-reusable.

The only exception here is if someone deliberately designs a new
password hashing scheme around Bitcoin mining, specifically to reuse
those ex-miners for defensive password hashing. Then the ex-miners
would also be usable offensively. But to my knowledge, no one does that
defensively, so there's also nothing to attack in this way.

Alexander

[Powen Cheng]

I understand better now and thank you for your insights.

“deliberately designs a new
password hashing scheme around Bitcoin mining“

Looks like something that is possible if pair with the right talents. I
guess one could always design ASIC or use FPGA.

On this note, any FPGA that is currently useable with john? I look briefly
and I wasn’t able to determine which is better GPU or FPGA.

Post by Solar Designer

Post by Powen Cheng
Even not through the use of open source of cgminer?

No.

Post by Powen Cheng
I would think solving
SHA256 hashes on this miner would be the same as solving hashes on JTR?

It isn't.
Bitcoin miners compute double-SHA-256 (not SHA-256) of block headers
(not passwords), in which they adjust the nonce field, and then compare
the result for being not greater than target (not for being equal to a
target hash). This is a sufficiently different task from what we have
in password cracking to make Bitcoin mining ASICs non-reusable.
The only exception here is if someone deliberately designs a new
password hashing scheme around Bitcoin mining, specifically to reuse
those ex-miners for defensive password hashing. Then the ex-miners
would also be usable offensively. But to my knowledge, no one does that
defensively, so there's also nothing to attack in this way.
Alexander

[Solar Designer]

Post by Powen Cheng
On this note, any FPGA that is currently useable with john?

Only ZTEX 1.15y (and its compatible clones), and only for 7 hash types
mentioned in:

https://www.openwall.com/lists/john-users/2018/10/12/1

Post by Powen Cheng
I look briefly
and I wasn't able to determine which is better GPU or FPGA.

It depends. For most purposes, you'd use GPU or/and sometimes CPU now.
For bcrypt and descrypt, you'd consider FPGA. If you have those FPGAs
anyway, then you'd also use them for the remaining 5 hash types.

For your current attempts with Tezos, it's just GPU and CPU.

Alexander