Issue #9168: now smtpd is able to bind privileged port.

Author: florentx

Lib/smtpd.py

@@ -678,6 +678,16 @@ def parseargs():
 if __name__ == '__main__':
     options = parseargs()
     # Become nobody
+    classname = options.classname
+    if "." in classname:
+        lastdot = classname.rfind(".")
+        mod = __import__(classname[:lastdot], globals(), locals(), [""])
+        classname = classname[lastdot+1:]
+    else:
+        import __main__ as mod
+    class_ = getattr(mod, classname)
+    proxy = class_((options.localhost, options.localport),
+                   (options.remotehost, options.remoteport))
     if options.setuid:
         try:
             import pwd
@@ -691,16 +701,6 @@ def parseargs():
             if e.errno != errno.EPERM: raise
             print('Cannot setuid "nobody"; try running with -n option.', file=sys.stderr)
             sys.exit(1)
-    classname = options.classname
-    if "." in classname:
-        lastdot = classname.rfind(".")
-        mod = __import__(classname[:lastdot], globals(), locals(), [""])
-        classname = classname[lastdot+1:]
-    else:
-        import __main__ as mod
-    class_ = getattr(mod, classname)
-    proxy = class_((options.localhost, options.localport),
-                   (options.remotehost, options.remoteport))
     try:
         asyncore.loop()
     except KeyboardInterrupt:

Misc/NEWS

@@ -322,6 +322,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #9168: now smtpd is able to bind privileged port.
+
 - Issue #12529: fix cgi.parse_header issue on strings with double-quotes and
   semicolons together. Patch by Ben Darnell and Petri Lehtinen.