lib/ip: Add method to convert the format of Ipv4 or Ipv6

Signed-off-by: Shinpei Muraoka <shinpei.muraoka@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

ryu/lib/ip.py

@@ -64,3 +64,34 @@ def ipv6_to_str(ip):
     :return: IPv6 address string
     """
     return addrconv.ipv6.bin_to_text(ip)
+
+
+def text_to_bin(ip):
+    """
+    Converts human readable IPv4 or IPv6 string to binary representation.
+    :param str ip: IPv4 or IPv6 address string
+    :return: binary representation of IPv4 or IPv6 address
+    """
+
+    if ':' not in ip:
+        data = addrconv.ipv4.text_to_bin(ip)
+    else:
+        data = addrconv.ipv6.text_to_bin(ip)
+
+    return data
+
+
+def bin_to_text(ip):
+    """
+    Converts binary representation to human readable IPv4 or IPv6 string.
+    :param ip: binary representation of IPv4 or IPv6 address
+    :return: IPv4 or IPv6 address string
+    """
+    if len(ip) == 4:
+        data = addrconv.ipv4.bin_to_text(ip)
+    elif len(ip) == 16:
+        data = addrconv.ipv6.bin_to_text(ip)
+    else:
+        raise struct.error('Invalid ip address length: %s' % len(ip))
+
+    return data

ryu/tests/unit/lib/test_ip.py

@@ -86,3 +86,29 @@ class Test_ip(unittest.TestCase):
         res = ip.ipv6_to_str(ipv6_bin)
         print('%s %s' % (val, res))
         eq_(val, res)
+
+    def test_text_to_bin_from_ipv4_text(self):
+        ipv4_str = '10.28.197.1'
+        val = struct.pack('!4B', 10, 28, 197, 1)
+        res = ip.text_to_bin(ipv4_str)
+        eq_(val, res)
+
+    def test_text_to_bin_from_ipv6_text(self):
+        ipv6_str = '2013:da8:215:8f2:aa20:66ff:fe4c:9c3c'
+        val = struct.pack('!8H', 0x2013, 0xda8, 0x215, 0x8f2, 0xaa20,
+                          0x66ff, 0xfe4c, 0x9c3c)
+        res = ip.text_to_bin(ipv6_str)
+        eq_(val, res)
+
+    def test_bin_to_text_from_ipv4_text(self):
+        ipv4_bin = struct.pack('!4B', 10, 28, 197, 1)
+        val = '10.28.197.1'
+        res = ip.bin_to_text(ipv4_bin)
+        eq_(val, res)
+
+    def test_bin_to_text_from_ipv6_text(self):
+        ipv6_bin = struct.pack('!8H', 0x2013, 0xda8, 0x215, 0x8f2, 0xaa20,
+                               0x66ff, 0xfe4c, 0x9c3c)
+        val = '2013:da8:215:8f2:aa20:66ff:fe4c:9c3c'
+        res = ip.bin_to_text(ipv6_bin)
+        eq_(val, res)