X-Git-Url: https://gerrit.onap.org/r/gitweb?a=blobdiff_plain;f=appc-core%2Fappc-common-bundle%2Fjava%2Forg%2Fonap%2Fappc%2Fencryption%2FHexHelper.java;fp=appc-core%2Fappc-common-bundle%2Fjava%2Forg%2Fonap%2Fappc%2Fencryption%2FHexHelper.java;h=9e975f84da3cd0a68bfe163bdd418ced42bcad58;hb=e35c3a0387e68bbeb3df8c5d614e0b99f5c4f743;hp=0000000000000000000000000000000000000000;hpb=344a44f3bb0762e5bc32a4ef760fb3b42ef4688d;p=appc.git

diff --git a/appc-core/appc-common-bundle/java/org/onap/appc/encryption/HexHelper.java b/appc-core/appc-common-bundle/java/org/onap/appc/encryption/HexHelper.java
new file mode 100644
index 000000000..9e975f84d
--- /dev/null
+++ b/appc-core/appc-common-bundle/java/org/onap/appc/encryption/HexHelper.java
@@ -0,0 +1,162 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP : APPC
+ * ================================================================================
+ * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Copyright (C) 2017 Amdocs
+ * =============================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.appc.encryption;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * HexHelper utility used for encryption/decryption
+ */
+public final class HexHelper {
+
+    @SuppressWarnings({
+        "javadoc", "nls"
+    })
+    public static final String CM_PATH = "@(#) [viewpath]/[item]";
+
+    @SuppressWarnings({
+        "nls", "javadoc"
+    })
+    public static final String CM_PROJECT = "@(#) [environment] [baseline]";
+
+    @SuppressWarnings({
+        "javadoc", "nls"
+    })
+    public static final String CM_VERSION = "@(#) [version] [crtime]";
+
+    private static final char[] HEX_TABLE = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D',
+        'E', 'F'};
+
+    /**
+     * The logger for this class.
+     */
+    private static final Logger LOG = LoggerFactory.getLogger(HexHelper.class);
+
+    private static Map<Character, Integer> textToHex;
+
+    static {
+        textToHex = new HashMap<>();
+        textToHex.put('0', 0);
+        textToHex.put('1', 1);
+        textToHex.put('2', 2);
+        textToHex.put('3', 3);
+        textToHex.put('4', 4);
+        textToHex.put('5', 5);
+        textToHex.put('6', 6);
+        textToHex.put('7', 7);
+        textToHex.put('8', 8);
+        textToHex.put('9', 9);
+        textToHex.put('A', 10);
+        textToHex.put('B', 11);
+        textToHex.put('C', 12);
+        textToHex.put('D', 13);
+        textToHex.put('E', 14);
+        textToHex.put('F', 15);
+    }
+
+    /**
+     * Default private constructor prevents instantiation
+     */
+    private HexHelper() {
+        // no-op
+    }
+
+    /**
+     * Converts an array of bytes to the equivalent string representation using hexadecimal notation
+     *
+     * @param bytes The bytes to be converted to a hexadecimal string
+     * @return The string representation
+     */
+    public static String convertBytesToHex(byte[] bytes) throws EncryptionException{
+
+        if (bytes == null)
+            throw new EncryptionException("Given byte array is null");
+
+        StringBuilder builder = new StringBuilder(bytes.length * 2);
+        for (byte aByte : bytes) {
+            char tempChar;
+            // Get the first 4 bits (high) Do bitwise logical AND to get rid of
+            // low nibble. Shift results to right by 4 and get char
+            // representation
+            tempChar = HEX_TABLE[(aByte & 0xf0) >>> 4];
+            builder.append(tempChar);
+
+            // Get the last 4 bits (low) Do bitwise logical AND to get rid of
+            // high nibble. Get char representation
+            tempChar = HEX_TABLE[aByte & 0x0f];
+            builder.append(tempChar);
+        }
+        return builder.toString();
+    }
+
+    /**
+     * Converts a hexadecimal string representation of a binary value to an array of bytes
+     *
+     * @param hexValue The hex representation string to be converted
+     * @return The array of bytes that contains the binary value
+     */
+    @SuppressWarnings("nls")
+    public static byte[] convertHexToBytes(String hexValue) throws EncryptionException {
+
+        if (hexValue ==null)
+            throw new EncryptionException("Given hex value is null");
+
+        byte[] bytes;
+        byte high;
+        byte low;
+        char hexChar;
+
+        StringBuilder builder = new StringBuilder(hexValue.toUpperCase());
+        if (builder.length() % 2 != 0) {
+            LOG.warn("Invalid HEX value length. The length of the value has to be a multiple of 2."
+                + " Prepending '0' value.");
+            builder.insert(0, '0');
+        }
+        int hexLength = builder.length();
+        int byteLength = hexLength / 2;
+
+        bytes = new byte[byteLength];
+        try {
+            for (int index = 0; index < hexLength; index += 2) {
+                hexChar = builder.charAt(index);
+                high = textToHex.get(hexChar).byteValue();
+                high = (byte) (high << 4);
+                hexChar = builder.charAt(index + 1);
+                low = textToHex.get(hexChar).byteValue();
+                high = (byte) (high | low);
+                bytes[index / 2] = high;
+            }
+        }
+        catch (NullPointerException e){
+            LOG.error("Given string contains not hexadecimal values", e);
+            throw new EncryptionException("Given string contains not hexadecimal values");
+        }
+
+        return bytes;
+    }
+}