tuerd: Get peer information from socket

[saartuer.git] / tuerd

diff --git a/tuerd b/tuerd
index 00b2420aade8493b21940f9d14ef2e0735e38d7b..f679fa896c2bc1ab75f9c28155630f06ad783507 100755 (executable)
--- a/tuerd
+++ b/tuerd
@@ -1,7 +1,8 @@
 #!/usr/bin/python3
-import time, socket, os, stat, atexit
+import time, socket, os, stat, atexit, errno, struct
 from datetime import datetime
 import RPi.GPIO as GPIO
+SO_PEERCRED = 17 # DO - NOT - TOUCH
 GPIO.setmode(GPIO.BOARD)
 
 # ******** definitions *********
@@ -25,8 +26,12 @@ def doNothing (conn):
 
 # delete a file, don't care if it did not exist in the first place
 def forcerm(name):
-       if os.path.exists(name):
+       try:
                os.unlink (name)
+       except OSError as e:
+               # only ignore error if it was "file didn't exist"
+               if e.errno != errno.ENOENT:
+                       raise
 
 # commands: on a pin do a series of timed on/off switches
 class Pinoutput:
@@ -85,7 +90,8 @@ sock.listen(1)
 while True:
        # accept connections
        conn, addr = sock.accept()
-       # TODO: use addr to determine the client for logging
+       # get peer information (TODO use it for logging)
+       (pid, uid, gid) = (struct.unpack('3i', conn.getsockopt(socket.SOL_SOCKET, SO_PEERCRED, struct.calcsize('3i'))))
        # get some data from the client (enough to hold any valid command)
        data = conn.recv (32)
        # log the command