change key_pass (rc4.c) function to run a range vs individual calls, shows a speedup of ~10,000 more passwords/sec for 128 bit encrypted files, and ~20,000 more for 40 bit encrypted files
Patch file for rc4.c
It does indeed speed it up.
Thank you for reporting!
I tried it out but could not see any speedup that was consistent (it was in reality slower on my system).
pdfcrack benchmarks are unfortunately not very reliable for small changes and it varies a lot depending on architecture and compiler setup (gcc 4.8 seems to make suboptimal register allocation in many cases for the current code for example).