Difference between revisions of "Compel"

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One thing parasite code can do is call clone() and create thread having access to main process VM, FDT, FS, etc. The new thread can then
 
One thing parasite code can do is call clone() and create thread having access to main process VM, FDT, FS, etc. The new thread can then
  
* Check socket FDs to get stuck/closed, re-open them and dup2() into original places
+
* Check socket FDs to get stuck/closed by polling them
** Problem: how to inform the original process about this change
 
 
* Apply "logrotate" on the fly
 
* Apply "logrotate" on the fly
  

Revision as of 13:09, 9 February 2016

[1]

Usage ideas

One thing parasite code can do is call clone() and create thread having access to main process VM, FDT, FS, etc. The new thread can then

  • Check socket FDs to get stuck/closed by polling them
  • Apply "logrotate" on the fly

Another is to do some activity on the victim and then just unload. With this we can

  • Death detection. Open pipe/socket and pass the other end outside. Once the victim dies the pipe/socket will wake up.
  • Binary updates. E.g. live patching or libr relink
  • Inject socket spy -- instead of opened socket create a unix one, put it in place of original one and send the latter back to caller so that any traffic flow in one goes "through" the spy
  • Do "nohup" on the fly
  • Debug stuff by MSG_PEEK-ing sockets messages of tee+splice sockets