bitmask-root: pep8'ed

1 files changed, 61 insertions, 41 deletions

diff --git a/pkg/linux/bitmask-root b/pkg/linux/bitmask-root
index 4463dbaa..6fbafff9 100755
--- a/pkg/linux/bitmask-root
+++ b/pkg/linux/bitmask-root
@@ -47,9 +47,9 @@ import traceback
 
 cmdcheck = subprocess.check_output
 
-##
-## CONSTANTS
-##
+#
+# CONSTANTS
+#
 
 VERSION = "1"
 SCRIPT = "bitmask-root"
@@ -121,9 +121,10 @@ if DEBUG:
 
 syslog.openlog(SCRIPT)
 
-##
-## UTILITY
-##
+#
+# UTILITY
+#
+
 
 def is_valid_address(value):
     """
@@ -207,7 +208,8 @@ def run(command, *args, **options):
       `detach`: If True, run in detached process.
       `input`: If True, open command for writing stream to, returning the Popen
                object.
-      `throw`: If True, raise an exception if there is an error instead of bailing.
+      `throw`: If True, raise an exception if there is an error instead
+               of bailing.
     """
     parts = [command]
     parts.extend(args)
@@ -233,9 +235,10 @@ def run(command, *args, **options):
         except subprocess.CalledProcessError as exc:
             if _exitcode:
                 if exc.returncode != 1:
-                    # 0 or 1 is to be expected, but anything else should be logged.
-                    debug("ERROR: Could not run %s: %s" % (exc.cmd, exc.output),
-                          exception=exc)
+                    # 0 or 1 is to be expected, but anything else
+                    # should be logged.
+                    debug("ERROR: Could not run %s: %s" %
+                          (exc.cmd, exc.output), exception=exc)
                 return exc.returncode
             elif _throw:
                 raise exc
@@ -264,6 +267,7 @@ def log(msg=None, exception=None, priority=syslog.LOG_INFO):
             traceback.print_exc()
         syslog.syslog(priority, traceback.format_exc())
 
+
 def debug(msg=None, exception=None):
     """
     Just like log, but is skipped unless DEBUG. Use syslog.LOG_INFO
@@ -272,6 +276,7 @@ def debug(msg=None, exception=None):
     if TEST or DEBUG:
         log(msg, exception)
 
+
 def bail(msg=None, exception=None):
     """
     abnormal exit. like log(), but exits with error status code.
@@ -279,9 +284,10 @@ def bail(msg=None, exception=None):
     log(msg, exception)
     exit(1)
 
-##
-## OPENVPN
-##
+#
+# OPENVPN
+#
+
 
 def get_openvpn_bin():
     """
@@ -314,14 +320,14 @@ def parse_openvpn_flags(args):
                     flag_params = flag[1:]
                     if len(flag_params) != len(required_params):
                         log("%s: ERROR: not enough params for %s" %
-                              (SCRIPT, flag_name))
+                            (SCRIPT, flag_name))
                         return None
                     for param, param_type in zip(flag_params, required_params):
                         if PARAM_FORMATS[param_type](param):
                             result.append(param)
                         else:
                             log("%s: ERROR: Bad argument %s" %
-                                  (SCRIPT, param))
+                                (SCRIPT, param))
                             return None
             else:
                 log("WARNING: unrecognized openvpn flag %s" % flag_name)
@@ -372,9 +378,10 @@ def openvpn_stop(args):
         pid = found_leap_openvpn[0][0]
         os.kill(int(pid), signal.SIGTERM)
 
-##
-## FIREWALL
-##
+#
+# FIREWALL
+#
+
 
 def get_gateways(gateways):
     """
@@ -492,6 +499,7 @@ def ip6tables(*args, **options):
 # the chain.
 #
 
+
 def ipv4_chain_exists(chain, table=None):
     """
     Check if a given chain exists. Only returns true if it actually exists,
@@ -501,10 +509,11 @@ def ipv4_chain_exists(chain, table=None):
     :type chain: str
     :rtype: bool
     """
-    if table:
-      code = run(IPTABLES, "-t", table, "--list", chain, "--numeric", exitcode=True)
+    if table is not None:
+        code = run(IPTABLES, "-t", table,
+                   "--list", chain, "--numeric", exitcode=True)
     else:
-      code = run(IPTABLES, "--list", chain, "--numeric", exitcode=True)
+        code = run(IPTABLES, "--list", chain, "--numeric", exitcode=True)
     if code == 0:
         return True
     elif code == 1:
@@ -531,13 +540,14 @@ def ipv6_chain_exists(chain):
         log("ERROR: Could not determine state of iptable chain")
         return False
 
+
 def enable_ip_forwarding():
     """
     ip_fowarding must be enabled for the firewall to work.
     """
-    file = open('/proc/sys/net/ipv4/ip_forward', 'w')
-    file.write('1\n')
-    file.close
+    with open('/proc/sys/net/ipv4/ip_forward', 'w') as f:
+        f.write('1\n')
+
 
 def firewall_start(args):
     """
@@ -562,7 +572,8 @@ def firewall_start(args):
     ip4tables("--table", "nat", "--insert", "OUTPUT", "--jump", BITMASK_CHAIN)
     iptables("--insert", "OUTPUT", "--jump", BITMASK_CHAIN)
 
-    # route all ipv4 DNS over VPN (note: NAT does not work with ipv6 until kernel 3.7)
+    # route all ipv4 DNS over VPN
+    # (note: NAT does not work with ipv6 until kernel 3.7)
     enable_ip_forwarding()
     # allow dns to localhost
     ip4tables("-t", "nat", "--append", BITMASK_CHAIN, "--protocol", "udp",
@@ -628,50 +639,59 @@ def firewall_start(args):
 
 def firewall_stop():
     """
-    Stop the firewall. Because we really really always want the firewall to be
-    stopped if at all possible, this function is cautious and contains a lot of
-    trys and excepts.
+    Stop the firewall. Because we really really always want the firewall to
+    be stopped if at all possible, this function is cautious and contains a
+    lot of trys and excepts.
 
-    If there were any problems, we raise an exception at the end. This allows the calling code
-    to retry stopping the firewall. Stopping the firewall can fail if iptables is being run by
-    another process (only one iptables command can be run at a time).
+    If there were any problems, we raise an exception at the end. This allows
+    the calling code to retry stopping the firewall. Stopping the firewall
+    can fail if iptables is being run by another process (only one iptables
+    command can be run at a time).
     """
     ok = True
     try:
         iptables("--delete", "OUTPUT", "--jump", BITMASK_CHAIN, throw=True)
     except subprocess.CalledProcessError as exc:
-        debug("INFO: not able to remove bitmask firewall from OUTPUT chain (maybe it is already removed?)", exc)
+        debug("INFO: not able to remove bitmask firewall from OUTPUT chain "
+              "(maybe it is already removed?)", exc)
         ok = False
     try:
-        ip4tables("-t", "nat", "--delete", "OUTPUT", "--jump", BITMASK_CHAIN, throw=True)
+        ip4tables("-t", "nat", "--delete", "OUTPUT",
+                  "--jump", BITMASK_CHAIN, throw=True)
     except subprocess.CalledProcessError as exc:
-        debug("INFO: not able to remove bitmask firewall from OUTPUT chain in 'nat' table (maybe it is already removed?)", exc)
+        debug("INFO: not able to remove bitmask firewall from OUTPUT chain "
+              "in 'nat' table (maybe it is already removed?)", exc)
         ok = False
     try:
         ip4tables("--flush", BITMASK_CHAIN, throw=True)
         ip4tables("--delete-chain", BITMASK_CHAIN, throw=True)
     except subprocess.CalledProcessError as exc:
-        debug("INFO: not able to flush and delete bitmask ipv4 firewall chain (maybe it is already destroyed?)", exc)
+        debug("INFO: not able to flush and delete bitmask ipv4 firewall "
+              "chain (maybe it is already destroyed?)", exc)
         ok = False
     try:
         ip4tables("-t", "nat", "--flush", BITMASK_CHAIN, throw=True)
         ip4tables("-t", "nat", "--delete-chain", BITMASK_CHAIN, throw=True)
     except subprocess.CalledProcessError as exc:
-        debug("INFO: not able to flush and delete bitmask ipv4 firewall chain in 'nat' table (maybe it is already destroyed?)", exc)
+        debug("INFO: not able to flush and delete bitmask ipv4 firewall "
+              "chain in 'nat' table (maybe it is already destroyed?)", exc)
         ok = False
     try:
         ip6tables("--flush", BITMASK_CHAIN, throw=True)
         ip6tables("--delete-chain", BITMASK_CHAIN, throw=True)
     except subprocess.CalledProcessError as exc:
-        debug("INFO: not able to flush and delete bitmask ipv6 firewall chain (maybe it is already destroyed?)", exc)
+        debug("INFO: not able to flush and delete bitmask ipv6 firewall "
+              "chain (maybe it is already destroyed?)", exc)
         ok = False
     if not (ok or ipv4_chain_exists or ipv6_chain_exists):
-        raise Exception("firewall might still be left up. Please try `firewall stop` again.")
+        raise Exception("firewall might still be left up. "
+                        "Please try `firewall stop` again.")
+
 
+#
+# MAIN
+#
 
-##
-## MAIN
-##
 
 def main():
     """