1 files changed, 188 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/util/IPAddress.java b/core/src/main/java/org/spongycastle/util/IPAddress.java
new file mode 100644
index 00000000..14c49cad
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/util/IPAddress.java
@@ -0,0 +1,188 @@
+package org.spongycastle.util;
+
+public class IPAddress
+{
+    /**
+     * Validate the given IPv4 or IPv6 address.
+     *
+     * @param address the IP address as a String.
+     *
+     * @return true if a valid address, false otherwise
+     */
+    public static boolean isValid(
+        String address)
+    {
+        return isValidIPv4(address) || isValidIPv6(address);
+    }
+
+    /**
+     * Validate the given IPv4 or IPv6 address and netmask.
+     *
+     * @param address the IP address as a String.
+     *
+     * @return true if a valid address with netmask, false otherwise
+     */
+    public static boolean isValidWithNetMask(
+        String address)
+    {
+        return isValidIPv4WithNetmask(address) || isValidIPv6WithNetmask(address);
+    }
+
+    /**
+     * Validate the given IPv4 address.
+     * 
+     * @param address the IP address as a String.
+     *
+     * @return true if a valid IPv4 address, false otherwise
+     */
+    public static boolean isValidIPv4(
+        String address)
+    {
+        if (address.length() == 0)
+        {
+            return false;
+        }
+
+        int octet;
+        int octets = 0;
+        
+        String temp = address+".";
+
+        int pos;
+        int start = 0;
+        while (start < temp.length()
+            && (pos = temp.indexOf('.', start)) > start)
+        {
+            if (octets == 4)
+            {
+                return false;
+            }
+            try
+            {
+                octet = Integer.parseInt(temp.substring(start, pos));
+            }
+            catch (NumberFormatException ex)
+            {
+                return false;
+            }
+            if (octet < 0 || octet > 255)
+            {
+                return false;
+            }
+            start = pos + 1;
+            octets++;
+        }
+
+        return octets == 4;
+    }
+
+    public static boolean isValidIPv4WithNetmask(
+        String address)
+    {
+        int index = address.indexOf("/");
+        String mask = address.substring(index + 1);
+
+        return (index > 0) && isValidIPv4(address.substring(0, index))
+                           && (isValidIPv4(mask) || isMaskValue(mask, 32));
+    }
+
+    public static boolean isValidIPv6WithNetmask(
+        String address)
+    {
+        int index = address.indexOf("/");
+        String mask = address.substring(index + 1);
+
+        return (index > 0) && (isValidIPv6(address.substring(0, index))
+                           && (isValidIPv6(mask) || isMaskValue(mask, 128)));
+    }
+
+    private static boolean isMaskValue(String component, int size)
+    {
+        try
+        {
+            int value = Integer.parseInt(component);
+
+            return value >= 0 && value <= size;
+        }
+        catch (NumberFormatException e)
+        {
+            return false;
+        }
+    }
+
+    /**
+     * Validate the given IPv6 address.
+     *
+     * @param address the IP address as a String.
+     *
+     * @return true if a valid IPv4 address, false otherwise
+     */
+    public static boolean isValidIPv6(
+        String address)
+    {
+        if (address.length() == 0)
+        {
+            return false;
+        }
+
+        int octet;
+        int octets = 0;
+
+        String temp = address + ":";
+        boolean doubleColonFound = false;
+        int pos;
+        int start = 0;
+        while (start < temp.length()
+            && (pos = temp.indexOf(':', start)) >= start)
+        {
+            if (octets == 8)
+            {
+                return false;
+            }
+
+            if (start != pos)
+            {
+                String value = temp.substring(start, pos);
+
+                if (pos == (temp.length() - 1) && value.indexOf('.') > 0)
+                {
+                    if (!isValidIPv4(value))
+                    {
+                        return false;
+                    }
+
+                    octets++; // add an extra one as address covers 2 words.
+                }
+                else
+                {
+                    try
+                    {
+                        octet = Integer.parseInt(temp.substring(start, pos), 16);
+                    }
+                    catch (NumberFormatException ex)
+                    {
+                        return false;
+                    }
+                    if (octet < 0 || octet > 0xffff)
+                    {
+                        return false;
+                    }
+                }
+            }
+            else
+            {
+                if (pos != 1 && pos != temp.length() - 1 && doubleColonFound)
+                {
+                    return false;
+                }
+                doubleColonFound = true;
+            }
+            start = pos + 1;
+            octets++;
+        }
+
+        return octets == 8 || doubleColonFound;
+    }
+}
+
+