From 84276816418e99ce7d7a795c1c98aa024f4c3cdf Mon Sep 17 00:00:00 2001
From: Milan Stute <mstute@seemoo.tu-darmstadt.de>
Date: Tue, 20 Aug 2019 11:48:15 +0200
Subject: [PATCH] Move from netifaces to ifaddr and add better error handling

Display message if `owl` is not running (fixes #7, fixes #12)
---
 opendrop/client.py |  9 ++++++---
 opendrop/server.py | 10 ++++++++--
 opendrop/util.py   | 39 ++++++++++++++++++++-------------------
 setup.py           |  2 +-
 4 files changed, 35 insertions(+), 25 deletions(-)

diff --git a/opendrop/client.py b/opendrop/client.py
index 4fb2d3a..c53ea40 100644
--- a/opendrop/client.py
+++ b/opendrop/client.py
@@ -40,10 +40,13 @@ class AirDropBrowser:
     def __init__(self, config):
         self.ip_interface_name = config.interface
 
-        self.ip_addr, self.byte_address = AirDropUtil.get_ip_for_interface(self.ip_interface_name, ipv6=True)
-
+        self.ip_addr = AirDropUtil.get_ip_for_interface(self.ip_interface_name, ipv6=True)
         if self.ip_addr is None:
-            raise RuntimeError('Interface {} does not have IP(v6) address'.format(self.ip_interface_name))
+            if self.ip_interface_name is 'awdl0':
+                raise RuntimeError('Interface {} does not have an IPv6 address. '
+                                   'Make sure that `owl` is running.'.format(self.ip_interface_name))
+            else:
+                raise RuntimeError('Interface {} does not have an IPv6 address'.format(self.ip_interface_name))
 
         self.zeroconf = Zeroconf(interfaces=[self.ip_addr], ipv6_interface_name=self.ip_interface_name)
 
diff --git a/opendrop/server.py b/opendrop/server.py
index 579780e..a543bc0 100644
--- a/opendrop/server.py
+++ b/opendrop/server.py
@@ -52,7 +52,13 @@ class AirDropServer:
 
         self.ServerClass.allow_reuse_address = False
 
-        self.ip_addr, self.byte_address = AirDropUtil.get_ip_for_interface(self.ip_interface_name, ipv6=True)
+        self.ip_addr = AirDropUtil.get_ip_for_interface(self.ip_interface_name, ipv6=True)
+        if self.ip_addr is None:
+            if self.ip_interface_name is 'awdl0':
+                raise RuntimeError('Interface {} does not have an IPv6 address. '
+                                   'Make sure that `owl` is running.'.format(self.ip_interface_name))
+            else:
+                raise RuntimeError('Interface {} does not have an IPv6 address'.format(self.ip_interface_name))
 
         self.Handler = AirDropServerHandler
         self.Handler.config = self.config
@@ -69,7 +75,7 @@ class AirDropServer:
         service_name = self.config.service_id + '._airdrop._tcp.local.'
         info = ServiceInfo(
             '_airdrop._tcp.local.', service_name,
-            self.byte_address, self.config.port, 0, 0, properties, server)
+            self.ip_addr.packed, self.config.port, 0, 0, properties, server)
         return info
 
     def start_service(self):
diff --git a/opendrop/util.py b/opendrop/util.py
index 98c5934..d08e031 100644
--- a/opendrop/util.py
+++ b/opendrop/util.py
@@ -17,8 +17,6 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <https://www.gnu.org/licenses/>.
 """
 
-import netifaces
-
 import base64
 import datetime
 import io
@@ -26,8 +24,8 @@ import ipaddress
 import os
 import platform
 import plistlib
-import socket
 import hashlib
+import ifaddr
 from PIL import Image, ExifTags
 from libarchive import ffi
 from libarchive.entry import new_archive_entry, ArchiveEntry
@@ -199,30 +197,33 @@ class AirDropUtil:
 
         return file_icon
 
-
     @staticmethod
     def get_ip_for_interface(interface_name, ipv6=False):
         """
         Get the ip address in IPv4 or IPv6 for a specific network interface
 
-        :param str interace_name: declares the network interface name for which the ip should be accessed
-        :param bool ipv6: Boolean indicating if the ipv6 address should be rertrieved
-        :return: (str ipaddress, byte ipaddress_bytes) returns a tuple with the ip address as a string and in bytes
+        :param str interface_name: declares the network interface name for which the ip should be accessed
+        :param bool ipv6: Boolean indicating if the ipv6 address should be retrieved
+        :return: IPv4Address or IPv6Address object or None
         """
-        addresses = netifaces.ifaddresses(interface_name)
 
-        if netifaces.AF_INET6 in addresses and ipv6:
-            # Use the normal ipv6 address
-            addr = addresses[netifaces.AF_INET6][0]['addr'].split('%')[0]
-            bytes_addr = ipaddress.IPv6Address(addr).packed
-        elif netifaces.AF_INET in addresses and not ipv6:
-            addr = addresses[netifaces.AF_INET][0]['addr']
-            bytes_addr = socket.inet_aton(addr)
-        else:
-            addr = None
-            bytes_addr = None
+        def get_interface_by_name(name):
+            for interface in ifaddr.get_adapters():
+                if interface.name == name:
+                    return interface
+            return None
 
-        return addr, bytes_addr
+        interface = get_interface_by_name(interface_name)
+        if interface is None:
+            return None
+
+        for ip in interface.ips:
+            if ip.is_IPv6 and ipv6:
+                return ipaddress.IPv6Address(ip.ip[0])  # first of (ip, flowinfo, scope_id) tuple
+            if ip.is_IPv4 and not ipv6:
+                return ipaddress.IPv4Address(ip.ip)
+
+        return None
 
     @staticmethod
     def write_debug(config, data, file_name):
diff --git a/setup.py b/setup.py
index b36b972..e9ce382 100644
--- a/setup.py
+++ b/setup.py
@@ -29,7 +29,7 @@ setup(
     package_data={
         'opendrop': ['certs/*.pem']
     },
-    install_requires=['requests', 'fleep', 'netifaces', 'Pillow',
+    install_requires=['requests', 'fleep', 'ifaddr', 'Pillow',
                       'requests_toolbelt', 'ctypescrypto', 'libarchive-c'],
     entry_points={
         'console_scripts': [