fix #138, add globbing to stdapi_fs_ls

[timwr]

This implements support for globbing on stdapi_fs_ls.
This is mostly useful because it fixes the tab completion :)

Unfortunately we still get:

meterpreter > ls me*
File globbing not supported with this session
meterpreter >

even though it is supported by this pr.
To fix that we can either implement stdapi_fs_search (in a separate pull request) or find another way for the framework side of things to know if globbing is supported.
See #138 for more details.

[timwr]

This is timing out currently on iOS

[busterb]

What do you mean by timing out?

[busterb]

We might just override glob in iOS's libc with the musl one unconditionally https://git.musl-libc.org/cgit/musl/tree/src/regex/glob.c

[timwr]

It seems the call to glob (https://github.com/rapid7/mettle/pull/139/files#diff-5bf4b5b8f1b639f9de20cda70d2fdb28R93) never returns so we get:

meterpreter > ls
[-] Error running command ls: Rex::TimeoutError Operation timed out

How would I go about overriding the libc version? Just add it to mettle/src/compat/glob.c?

[busterb]

That could be one way. If glob is not a weak symbol in libc (meaning you can easily override it via the linker), you could also rename the exported function to 'musl_glob' or something.

If you wanted to selectively redirect 'glob' to 'musl_glob' then, you could do something like this with a preprocessor define, or just call it directly: https://github.com/libressl-portable/portable/blob/master/include/compat/stdio.h#L33

[busterb]

Marking this unblocked, @space-r7 and I can look at it today.

[busterb]

Looks good, landing.

[busterb]

Now that we have this, I say we just go ahead and implement fs_search. I can probably pull that together real quick since we have the primitives.