Move command_exists? to Msf::Post::Common

[wvu]

And add rudimentary Windows support.

meterpreter > run post/linux/gather/hashdump

[+] vagrant:$6$pjYWAc.5$QYfO.wN80gnGe2kC1jYmSTGmO/qelG1CMl6ubKMbDQt9b1TEKZ648PQGI7VC88XE3ObdPBswUavsC1eDVZunJ.:1000:1000:,,,:/home/vagrant:/bin/bash
[+] Unshadowed Password File: /Users/wvu/.msf4/loot/20190131221240_default_172.28.128.3_linux.hashes_959802.txt
meterpreter >

[1] pry(#<Msf::Modules::Post__Linux__Gather__Hashdump::MetasploitModule>)> command_exists?('calc')
=> true
[2] pry(#<Msf::Modules::Post__Linux__Gather__Hashdump::MetasploitModule>)> command_exists?('nope')
=> false
[3] pry(#<Msf::Modules::Post__Linux__Gather__Hashdump::MetasploitModule>)>

Fixes #11334, hopefully. See #10119 for the regression.

[bcoles]

Seems legit. I, personally, don't care about Windows support.

[wvu]

It's in Msf::Post::Common, so I figured I'd give it something extra. If you want to drop Windows support, move it out of Common.

[bcoles]

It's in Msf::Post::Common, so I figured I'd give it something extra. If you want to drop Windows support, move it out of Common.

Windows support makes sense and is good. I don't care whether the implementation is sane.

[bcoles]

This probably won't fix the 3 instances of command_exists? in the File API.

https://github.com/rapid7/metasploit-framework/blob/master/lib/msf/core/post/file.rb

Fortunately, most modules which make use of Post File also import Post Common.

[wvu]

I read some docs, found some shit, and wrote it up. I'll post the test results in the PR description, but I don't care if the Windows implementation gets tested, and I'm not going to put more effort into it.

Let's fix the outstanding issue.

[wvu]

Msf::Post::Common is included in Msf::PostMixin, which is included by all post modules and local exploits.

[bcoles]

Release Notes

This fix moves the command_exists? method to Msf::Post::Common.

[wvu]

Thanks!

[h00die]

Thanks team for handling this!
Should I resubmit my PR, or just put a note to incorporate this first?

[wvu]

I'm not sure I understand. Base your work against master.

[bcoles]

@h00die I'd go with option 2: leave a note.