Add mixin to implement an exploit's check method by invoking a scanner

[wvu]

This PR adds a check method to the ms17_010_eternalblue exploit by calling the smb_ms17_010 scanner and checking its newly added return value. This is now a mixin. This was a big to-do for us in the past.

We may want to make this kind of code more generic between exploits and auxiliary modules.

msf5 exploit(windows/smb/ms17_010_eternalblue) > check

[*] 192.168.56.103:445    - Connected to \\192.168.56.103\IPC$ with TID = 2049
[*] 192.168.56.103:445    - Received STATUS_INSUFF_SERVER_RESOURCES with FID = 0
[+] 192.168.56.103:445    - Host is likely VULNERABLE to MS17-010! - Windows Server 2008 R2 Standard 7601 Service Pack 1 x64 (64-bit)
[+] 192.168.56.103:445 - The target is vulnerable.
msf5 exploit(windows/smb/ms17_010_eternalblue) >

cc @zerosum0x0

#8271, #8381, #11869

[ghost]

Nice! I had wanted to do something like this originally but didn't know enough about the framework at the time.

[wvu]

I'm thinking if someone writes an RDP exploit, we can just repurpose the scanner in a similar manner. 😅

[wvu]

@zerosum0x0: This is a mixin now, and I plan to flesh it out even further for generic usage. When the RDP exploit comes in, your scanner can be called directly.

[busterb]

LGTM, thanks.

[busterb]

Release Notes

This adds a new mixin that allows modules to call methods in other modules easily, namely allowing check methods to be shared between scanner and exploit modules.