C++/OpenSSL SHA1 miner

Miner finds a nonce for a given prefix and difficulty by using multithread brute force algorithm.

Top level algorithm

1. Calculate SHA1 for the prefix and padding to 512 bits. This step optimizes further hash generation because sha1 won't rehash the prefix when it's padded correctly.
2. Increment or randomize nonce on the every next step and continue until hash with a given difficulty not found.

Build

1. Install openssl binaries and headers, make, and C++17 compiler;
2. Adjust Makefile;
3. run make.

Use

./sha1-miner some-prefix -d 5 -t 2

Runs miner in two threads to find a hash with difficulty 5.

Run ./sha1-miner -h for info.

Examples

Use sequential nonce search

One thread

./sha1-miner "hello world" -d 7 -t 1 -p
hello world0000000000000000000000000000000000000000000000000000000000000000efyMs
0000000fc220ad3cfd3647556e8ed3657173a9ad
Hashrate is 9.43239M/s

Two threads

./sha1-miner "hello world" -d 7 -t 2 -p
hello world0000000000000000000000000000000000000000000000000000000000000000efyMs
0000000fc220ad3cfd3647556e8ed3657173a9ad
Hashrate is 17.5783M/s

Use random nonce generation

./sha1-miner "hello world" -d 7 -t 2 -p -r
hello world000000000000000000000000000000000000000000000000000009ItwHhN0Am0VC3NH
0000000367e43c366b7431f25f0ff860b939607b
Hashrate is 8.02728M/s

TODO

• To progress when the first-round nonce counting doesn't give a result.
• Uptimize random suffix generation.