From a quick look (so I may be mistaken), the "Enigma" worksheet has everything it needs to encode a single letter using worksheet formulae.
The VBA just loops through the input text, feeding it into the worksheet character by character and incrementing the step counts, which are referred to by the worksheet formulae. It also looks up the initial rotor positions from the "Settings" table from the "keys" on the main interface worksheet.
That's for encryption - there are another 30 lines of code for decryption which I haven't looked at. It looks hand-coded rather than recorded, but most of the VBA is either incrementing counters or calling worksheet functions, so the VBA isn't doing the heavy lifting.
Your friend may not call himself a programmer but I do Excel/VBA work as part of my job, along with more hacker-approved languages, and I'm very impressed. One of us indeed!
The VBA just loops through the input text, feeding it into the worksheet character by character and incrementing the step counts, which are referred to by the worksheet formulae. It also looks up the initial rotor positions from the "Settings" table from the "keys" on the main interface worksheet.
That's for encryption - there are another 30 lines of code for decryption which I haven't looked at. It looks hand-coded rather than recorded, but most of the VBA is either incrementing counters or calling worksheet functions, so the VBA isn't doing the heavy lifting.
Your friend may not call himself a programmer but I do Excel/VBA work as part of my job, along with more hacker-approved languages, and I'm very impressed. One of us indeed!