Make gen_dns working with python3

Makefile

@@ -1,7 +1,7 @@
 
 .PHONY: all
 all: linux_tools/bpf_dbg linux_tools/bpf_asm
-	python -c "import pcappy"
+	python3 -c "import pcappy"
 
 
 linux_tools/bpf_dbg: linux_tools/*.[ch]
@@ -11,4 +11,4 @@ linux_tools/bpf_asm: linux_tools/*.[ch]
 	make -C linux_tools bpf_asm
 
 test:
-	python -m unittest discover tests/
+	python3 -m unittest discover tests/

README.md

@@ -19,9 +19,9 @@ To run these scripts you will need:
 
  - Installed dependencies:
 
-        $ sudo apt-get install python-setuptools libpcap-dev \
+        $ sudo apt-get install python3-setuptools libpcap-dev \
                                libreadline-dev binutils-dev bison flex
-        $ sudo easy_install pcappy
+        $ pip install git+https://github.com/allfro/pcappy
 
  - Build the binary tools in `linux_tools` directory:
 

bpfgen

@@ -1,5 +1,6 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
+from __future__ import print_function
 import argparse
 import os
 import stat
@@ -12,7 +13,7 @@ import bpftools
 def main():
     parser = argparse.ArgumentParser(
         formatter_class=argparse.RawDescriptionHelpFormatter,
-        description=r'''
+        description=r"""
 
 This tool creates a Berkeley Packet Filter (BPF) bytecode that will
 match packets based on given criteria. Right now we support the
@@ -43,35 +44,44 @@ BPF generators, for example:
     %(prog)s -s -n suffix -- 010203
     %(prog)s -s -n -o 14 suffix -- 010203
     %(prog)s -s -n -o 14 -6 suffix -- 010203
-    ''')
-
-    parser.add_argument('-6', '--inet6', action='store_true',
-                        help='generate script for IPv6')
-    parser.add_argument('-n', '--negate', action='store_true',
-                        help='negate the logic')
-    parser.add_argument('-o', '--offset', type=int, default=0,
-                        help='offset of an L3 header')
-    parser.add_argument('-s', '--assembly', action='store_true',
-                        help='print readable assembly, not numeric bytecode')
-    parser.add_argument('type', nargs=1, choices=bpftools.generator_names,
-                        help='BPF generator type')
-    parser.add_argument('parameters', nargs='*',
-                        help='parameters passed to the BPF generator')
+    """,
+    )
+
+    parser.add_argument(
+        "-6", "--inet6", action="store_true", help="generate script for IPv6"
+    )
+    parser.add_argument("-n", "--negate", action="store_true", help="negate the logic")
+    parser.add_argument(
+        "-o", "--offset", type=int, default=0, help="offset of an L3 header"
+    )
+    parser.add_argument(
+        "-s",
+        "--assembly",
+        action="store_true",
+        help="print readable assembly, not numeric bytecode",
+    )
+    parser.add_argument(
+        "type", nargs=1, choices=bpftools.generator_names, help="BPF generator type"
+    )
+    parser.add_argument(
+        "parameters", nargs="*", help="parameters passed to the BPF generator"
+    )
 
     args = parser.parse_args()
 
     if len(args.type) != 1:
         parser.print_help()
         sys.exit(-1)
 
-    name, ret = bpftools.gen(args.type[0],
-                             args.parameters,
-                             assembly=args.assembly,
-                             l3_off=args.offset,
-                             ipversion=4 if not args.inet6 else 6,
-                             negate=args.negate,
-                             )
-    print ret
+    name, ret = bpftools.gen(
+        args.type[0],
+        args.parameters,
+        assembly=args.assembly,
+        l3_off=args.offset,
+        ipversion=4 if not args.inet6 else 6,
+        negate=args.negate,
+    )
+    print(ret)
 
 
 if __name__ == "__main__":

bpftools/__init__.py

@@ -1,4 +1,10 @@
-import StringIO as stringio
+#!/usr/bin/env python3
+
+from __future__ import print_function
+from future import standard_library
+
+standard_library.install_aliases()
+import io as stringio
 import os
 import sys
 
@@ -10,29 +16,31 @@
 from . import gen_tcpdump
 
 name_to_gen = {
-    'dns': gen_dns.gen,
-    'dns_validate': gen_dns_validate.gen,
-    'p0f': gen_p0f.gen,
-    'suffix': gen_suffix.gen,
-    'tcpdump': gen_tcpdump.gen,
-    }
+    "dns": gen_dns.gen,
+    "dns_validate": gen_dns_validate.gen,
+    "p0f": gen_p0f.gen,
+    "suffix": gen_suffix.gen,
+    "tcpdump": gen_tcpdump.gen,
+}
 
-generator_names = name_to_gen.keys()
+generator_names = list(name_to_gen.keys())
 
 
 def gen(typename, params, **kwargs):
     gentype = name_to_gen[typename]
 
-    assembly = kwargs.get('assembly', False)
-    del kwargs['assembly']
+    assembly = kwargs.get("assembly", False)
+    del kwargs["assembly"]
 
     sys.stdout, saved_stdout = stringio.StringIO(), sys.stdout
+
     def new_exit(s):
         sys.stdout.seek(0)
         data = sys.stdout.read()
         sys.stdout = saved_stdout
-        print data
+        print(data)
         os._exit(s)
+
     sys.exit, saved_exit = new_exit, sys.exit
 
     name = gentype(params, **kwargs)