15 Jun
2023
15 Jun
'23
2:03 a.m.
After writing this mail I actually started reversing the B binaries.
You can find them here: http://squoze.net/B/programs/
I did find some differences in versions of the B runtime and library.
Especially interesting was an implementation of the cksto routine
in su and stty that checks whether an address in an assignment is in a
reasonable range ("LV out of range" error if not)
What is perhaps interesting historically is that the su binary contains
a hardcoded password ^Q^R^S^T, which is not printable for a good reason:
it is given as a command line argument.
I will hopefully continue with this in the next time (if, goto, mail and
glob are left).
Best,
aap
On 14/06/23, Angelo Papenhoff wrote:
Thank you two for finding this!
I did some disassembling yesterday and have uploaded brt1.s and brt2.s
to my site now: http://squoze.net/B/brt/ (I haven't actually assembled
them yet, there may be mistakes)
Some observations:
- The 'chain' format is actually a linked list and not a list of
addresses. Phil and I both got this wrong.
- The "Init" string is an error message if for some reason the B init
chain didn't run or main doesn't look like a function
- The cmdline arguments overwrite part of the init code. There's about
80 bytes of space for them before it overwrites the code that builds the
argv vector
- brt2.s is only to mark the beginning of the stack
I also saw some differences in the bilib code but haven't really
analyzed that part (yet?)
Would be really great if we could get all the files disassembled and
decompiled and restore the source code for everything :)
Best,
Angelo