Add to symbol table for reverse engineering?

[Nate Eldredge <neldredge@math.ucsd.edu>]

Hi all,

I am trying to reverse engineer a stripped binary using gdb.  I wonder if 
there is a way to interactively add symbols as I go.  For example, suppose 
I discover that 0xdeadbeef is the address of a function that does "foo". 
Presumably the binary originally had an entry "foo = 0xdeadbeef" in its 
symbol table, which is now gone.  I would like to be able to "put it back" 
and use it with gdb's convenient symbol features.  For instance, if I come 
across a "call 0xdeadbeef" instruction elsewhere in the program, I would 
like the gdb disassembler to tag it as "call 0xdeadbeef <foo>".  Is there 
any way to do this?  I didn't see such a thing in the manual.

I know I can do:

set $foo = 0xdeadbeef


so that at least the address is saved, but gdb won't do the reverse 
translation in disassembly.

I suppose it is possible to keep an external symbol table which I load, 
but then I would have to have a separate file which I have to paste in 
stuff from gdb, and then reload it every time I add something new.

-- 

Nate Eldredge
neldredge@math.ucsd.edu