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-/*******************************************************************************
- * ============LICENSE_START====================================================
- * * org.onap.aaf
- * * ===========================================================================
- * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
- * * ===========================================================================
- * * 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====================================================
- * *
- * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
- * *
- ******************************************************************************/
-package org.onap.aaf.cadi;
-
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.security.SecureRandom;
-import java.util.ArrayList;
-import java.util.Random;
-
-import javax.crypto.CipherInputStream;
-import javax.crypto.CipherOutputStream;
-
-import org.onap.aaf.cadi.Access.Level;
-import org.onap.aaf.cadi.config.Config;
-
-/**
- * Key Conversion, primarily "Base64"
- *
- * Base64 is required for "Basic Authorization", which is an important part of the overall CADI Package.
- *
- * Note: This author found that there is not a "standard" library for Base64 conversion within Java.
- * The source code implementations available elsewhere were surprisingly inefficient, requiring, for
- * instance, multiple string creation, on a transaction pass. Integrating other packages that might be
- * efficient enough would put undue Jar File Dependencies given this Framework should have none-but-Java
- * dependencies.
- *
- * The essential algorithm is good for a symmetrical key system, as Base64 is really just
- * a symmetrical key that everyone knows the values.
- *
- * This code is quite fast, taking about .016 ms for encrypting, decrypting and even .08 for key
- * generation. The speed quality, especially of key generation makes this a candidate for a short term token
- * used for identity.
- *
- * It may be used to easily avoid placing Clear-Text passwords in configurations, etc. and contains
- * supporting functions such as 2048 keyfile generation (see keygen). This keyfile should, of course,
- * be set to "400" (Unix) and protected as any other mechanism requires.
- *
- * However, this algorithm has not been tested against hackers. Until such a time, utilize more tested
- * packages to protect Data, especially sensitive data at rest (long term).
- *
- */
-public class Symm {
- private static final byte[] DOUBLE_EQ = new byte[] {'=','='};
- public static final String ENC = "enc:";
- private static final SecureRandom random = new SecureRandom();
-
- public final char[] codeset;
- private final int splitLinesAt;
- private final String encoding;
- private final Convert convert;
- private final boolean endEquals;
- //Note: AES Encryption is not Thread Safe. It is Synchronized
- private static AES aes = null; // only initialized from File, and only if needed for Passwords
-
- /**
- * This is the standard base64 Key Set.
- * RFC 2045
- */
- public static final Symm base64 = new Symm(
- "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray()
- ,76, Config.UTF_8,true);
-
- public static final Symm base64noSplit = new Symm(
- "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray()
- ,Integer.MAX_VALUE, Config.UTF_8,true);
-
- /**
- * This is the standard base64 set suitable for URLs and Filenames
- * RFC 4648
- */
- public static final Symm base64url = new Symm(
- "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_".toCharArray()
- ,76, Config.UTF_8,true);
-
- /**
- * A Password set, using US-ASCII
- * RFC 4648
- */
- public static final Symm encrypt = new Symm(base64url.codeset,1024, "US-ASCII", false);
-
- /**
- * A typical set of Password Chars
- * Note, this is too large to fit into the algorithm. Only use with PassGen
- */
- private static char passChars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+!@#$%^&*(){}[]?:;,.".toCharArray();
-
-
-
- /**
- * Use this to create special case Case Sets and/or Line breaks
- *
- * If you don't know why you need this, use the Singleton Method
- *
- * @param codeset
- * @param split
- */
- public Symm(char[] codeset, int split, String charset, boolean useEndEquals) {
- this.codeset = codeset;
- splitLinesAt = split;
- encoding = charset;
- endEquals = useEndEquals;
- char prev = 0, curr=0, first = 0;
- int offset=Integer.SIZE; // something that's out of range for integer array
-
- // There can be time efficiencies gained when the underlying keyset consists mainly of ordered
- // data (i.e. abcde...). Therefore, we'll quickly analyze the keyset. If it proves to have
- // too much entropy, the "Unordered" algorithm, which is faster in such cases is used.
- ArrayList<int[]> la = new ArrayList<int[]>();
- for(int i=0;i<codeset.length;++i) {
- curr = codeset[i];
- if(prev+1==curr) { // is next character in set
- prev = curr;
- } else {
- if(offset!=Integer.SIZE) { // add previous range
- la.add(new int[]{first,prev,offset});
- }
- first = prev = curr;
- offset = curr-i;
- }
- }
- la.add(new int[]{first,curr,offset});
- if(la.size()>codeset.length/3) {
- convert = new Unordered(codeset);
- } else { // too random to get speed enhancement from range algorithm
- int[][] range = new int[la.size()][];
- la.toArray(range);
- convert = new Ordered(range);
- }
- }
-
- public Symm copy(int lines) {
- return new Symm(codeset,lines,encoding,endEquals);
- }
-
- // Only used by keygen, which is intentionally randomized. Therefore, always use unordered
- private Symm(char[] codeset, Symm parent) {
- this.codeset = codeset;
- splitLinesAt = parent.splitLinesAt;
- endEquals = parent.endEquals;
- encoding = parent.encoding;
- convert = new Unordered(codeset);
- }
-
- /**
- * Obtain the base64() behavior of this class, for use in standard BASIC AUTH mechanism, etc.
- * @return
- */
- @Deprecated
- public static final Symm base64() {
- return base64;
- }
-
- /**
- * Obtain the base64() behavior of this class, for use in standard BASIC AUTH mechanism, etc.
- * No Line Splitting
- * @return
- */
- @Deprecated
- public static final Symm base64noSplit() {
- return base64noSplit;
- }
-
- /**
- * Obtain the base64 "URL" behavior of this class, for use in File Names, etc. (no "/")
- */
- @Deprecated
- public static final Symm base64url() {
- return base64url;
- }
-
- /**
- * Obtain a special ASCII version for Scripting, with base set of base64url use in File Names, etc. (no "/")
- */
- public static final Symm baseCrypt() {
- return encrypt;
- }
-
- /*
- * Note: AES Encryption is NOT thread-safe. Must surround entire use with synchronized
- */
- private synchronized void exec(AESExec exec) throws IOException {
- if(aes == null) {
- try {
- byte[] bytes = new byte[AES.AES_KEY_SIZE/8];
- int offset = (Math.abs(codeset[0])+47)%(codeset.length-bytes.length);
- for(int i=0;i<bytes.length;++i) {
- bytes[i] = (byte)codeset[i+offset];
- }
- aes = new AES(bytes,0,bytes.length);
- } catch (Exception e) {
- throw new IOException(e);
- }
- }
- exec.exec(aes);
- }
-
- private static interface AESExec {
- public void exec(AES aes) throws IOException;
- }
-
- public byte[] encode(byte[] toEncrypt) throws IOException {
- ByteArrayOutputStream baos = new ByteArrayOutputStream((int)(toEncrypt.length*1.25));
- encode(new ByteArrayInputStream(toEncrypt),baos);
- return baos.toByteArray();
- }
-
- public byte[] decode(byte[] encrypted) throws IOException {
- ByteArrayOutputStream baos = new ByteArrayOutputStream((int)(encrypted.length*1.25));
- decode(new ByteArrayInputStream(encrypted),baos);
- return baos.toByteArray();
- }
-
- /**
- * Helper function for String API of "Encode"
- * use "getBytes" with appropriate char encoding, etc.
- *
- * @param str
- * @return
- * @throws IOException
- */
- public String encode(String str) throws IOException {
- byte[] array;
- try {
- array = str.getBytes(encoding);
- } catch (IOException e) {
- array = str.getBytes(); // take default
- }
- // Calculate expected size to avoid any buffer expansion copies within the ByteArrayOutput code
- ByteArrayOutputStream baos = new ByteArrayOutputStream((int)(array.length*1.363)); // account for 4 bytes for 3 and a byte or two more
-
- encode(new ByteArrayInputStream(array),baos);
- return baos.toString(encoding);
- }
-
- /**
- * Helper function for the String API of "Decode"
- * use "getBytes" with appropriate char encoding, etc.
- * @param str
- * @return
- * @throws IOException
- */
- public String decode(String str) throws IOException {
- byte[] array;
- try {
- array = str.getBytes(encoding);
- } catch (IOException e) {
- array = str.getBytes(); // take default
- }
- // Calculate expected size to avoid any buffer expansion copies within the ByteArrayOutput code
- ByteArrayOutputStream baos = new ByteArrayOutputStream((int)(array.length*.76)); // Decoding is 3 bytes for 4. Allocate slightly more than 3/4s
- decode(new ByteArrayInputStream(array), baos);
- return baos.toString(encoding);
- }
-
- /**
- * Convenience Function
- *
- * encode String into InputStream and call encode(InputStream, OutputStream)
- *
- * @param string
- * @param out
- * @throws IOException
- */
- public void encode(String string, OutputStream out) throws IOException {
- encode(new ByteArrayInputStream(string.getBytes()),out);
- }
-
- /**
- * Convenience Function
- *
- * encode String into InputStream and call decode(InputStream, OutputStream)
- *
- * @param string
- * @param out
- * @throws IOException
- */
- public void decode(String string, OutputStream out) throws IOException {
- decode(new ByteArrayInputStream(string.getBytes()),out);
- }
-
- public void encode(InputStream is, OutputStream os, byte[] prefix) throws IOException {
- os.write(prefix);
- encode(is,os);
- }
-
- /**
- * encode InputStream onto Output Stream
- *
- * @param is
- * @param estimate
- * @return
- * @throws IOException
- */
- public void encode(InputStream is, OutputStream os) throws IOException {
- // StringBuilder sb = new StringBuilder((int)(estimate*1.255)); // try to get the right size of StringBuilder from start.. slightly more than 1.25 times
- int prev=0;
- int read, idx=0, line=0;
- boolean go;
- do {
- read = is.read();
- if(go = read>=0) {
- if(line>=splitLinesAt) {
- os.write('\n');
- line = 0;
- }
- switch(++idx) { // 1 based reading, slightly faster ++
- case 1: // ptr is the first 6 bits of read
- os.write(codeset[read>>2]);
- prev = read;
- break;
- case 2: // ptr is the last 2 bits of prev followed by the first 4 bits of read
- os.write(codeset[((prev & 0x03)<<4) | (read>>4)]);
- prev = read;
- break;
- default: //(3+)
- // Char 1 is last 4 bits of prev plus the first 2 bits of read
- // Char 2 is the last 6 bits of read
- os.write(codeset[(((prev & 0xF)<<2) | (read>>6))]);
- if(line==splitLinesAt) { // deal with line splitting for two characters
- os.write('\n');
- line=0;
- }
- os.write(codeset[(read & 0x3F)]);
- ++line;
- idx = 0;
- prev = 0;
- }
- ++line;
- } else { // deal with any remaining bits from Prev, then pad
- switch(idx) {
- case 1: // just the last 2 bits of prev
- os.write(codeset[(prev & 0x03)<<4]);
- if(endEquals)os.write(DOUBLE_EQ);
- break;
- case 2: // just the last 4 bits of prev
- os.write(codeset[(prev & 0xF)<<2]);
- if(endEquals)os.write('=');
- break;
- }
- idx = 0;
- }
-
- } while(go);
- }
-
- public void decode(InputStream is, OutputStream os, int skip) throws IOException {
- is.skip(skip);
- decode(is,os);
- }
-
- /**
- * Decode InputStream onto OutputStream
- * @param is
- * @param os
- * @throws IOException
- */
- public void decode(InputStream is, OutputStream os) throws IOException {
- int read, idx=0;
- int prev=0, index;
- while((read = is.read())>=0) {
- index = convert.convert(read);
- if(index>=0) {
- switch(++idx) { // 1 based cases, slightly faster ++
- case 1: // index goes into first 6 bits of prev
- prev = index<<2;
- break;
- case 2: // write second 2 bits of into prev, write byte, last 4 bits go into prev
- os.write((byte)(prev|(index>>4)));
- prev = index<<4;
- break;
- case 3: // first 4 bits of index goes into prev, write byte, last 2 bits go into prev
- os.write((byte)(prev|(index>>2)));
- prev = index<<6;
- break;
- default: // (3+) | prev and last six of index
- os.write((byte)(prev|(index&0x3F)));
- idx = prev = 0;
- }
- }
- };
- os.flush();
- }
-
- /**
- * Interface to allow this class to choose which algorithm to find index of character in Key
- *
- */
- private interface Convert {
- public int convert(int read) throws IOException;
- }
-
- /**
- * Ordered uses a range of orders to compare against, rather than requiring the investigation
- * of every character needed.
- *
- */
- private static final class Ordered implements Convert {
- private int[][] range;
- public Ordered(int[][] range) {
- this.range = range;
- }
- public int convert(int read) throws IOException {
- switch(read) {
- case -1:
- case '=':
- case '\n':
- return -1;
- }
- for(int i=0;i<range.length;++i) {
- if(read >= range[i][0] && read<=range[i][1]) {
- return read-range[i][2];
- }
- }
- throw new IOException("Unacceptable Character in Stream");
- }
- }
-
- /**
- * Unordered, i.e. the key is purposely randomized, simply has to investigate each character
- * until we find a match.
- *
- */
- private static final class Unordered implements Convert {
- private char[] codec;
- public Unordered(char[] codec) {
- this.codec = codec;
- }
- public int convert(int read) throws IOException {
- switch(read) {
- case -1:
- case '=':
- case '\n':
- return -1;
- }
- for(int i=0;i<codec.length;++i) {
- if(codec[i]==read)return i;
- }
- // don't give clue in Encryption mode
- throw new IOException("Unacceptable Character in Stream");
- }
- }
-
- /**
- * Generate a 2048 based Key from which we extract our code base
- *
- * @return
- * @throws IOException
- */
- public byte[] keygen() throws IOException {
- byte inkey[] = new byte[0x600];
- new SecureRandom().nextBytes(inkey);
- ByteArrayOutputStream baos = new ByteArrayOutputStream(0x800);
- base64url.encode(new ByteArrayInputStream(inkey), baos);
- return baos.toByteArray();
- }
-
- // A class allowing us to be less predictable about significant digits (i.e. not picking them up from the
- // beginning, and not picking them up in an ordered row. Gives a nice 2048 with no visible patterns.
- private class Obtain {
- private int last;
- private int skip;
- private int length;
- private byte[] key;
-
- private Obtain(Symm b64, byte[] key) {
- skip = Math.abs(key[key.length-13]%key.length);
- if((key.length&0x1) == (skip&0x1)) { // if both are odd or both are even
- ++skip;
- }
- length = b64.codeset.length;
- last = 17+length%59; // never start at beginning
- this.key = key;
- }
-
- private int next() {
- return Math.abs(key[(++last*skip)%key.length])%length;
- }
- };
-
- /**
- * Obtain a Symm from "keyfile" (Config.KEYFILE) property
- *
- * @param acesss
- * @return
- */
- public static Symm obtain(Access access) {
- Symm symm = Symm.baseCrypt();
-
- String keyfile = access.getProperty(Config.CADI_KEYFILE,null);
- if(keyfile!=null) {
- File file = new File(keyfile);
- try {
- access.log(Level.INIT, Config.CADI_KEYFILE,"points to",file.getCanonicalPath());
- } catch (IOException e1) {
- access.log(Level.INIT, Config.CADI_KEYFILE,"points to",file.getAbsolutePath());
- }
- if(file.exists()) {
- try {
- FileInputStream fis = new FileInputStream(file);
- try {
- symm = Symm.obtain(fis);
- } finally {
- try {
- fis.close();
- } catch (IOException e) {
- }
- }
- } catch (IOException e) {
- access.log(e, "Cannot load keyfile");
- }
- }
- }
- return symm;
- }
- /**
- * Create a new random key
- */
- public Symm obtain() throws IOException {
- byte inkey[] = new byte[0x800];
- new SecureRandom().nextBytes(inkey);
- return obtain(inkey);
- }
-
- /**
- * Obtain a Symm from 2048 key from a String
- *
- * @param key
- * @return
- * @throws IOException
- */
- public static Symm obtain(String key) throws IOException {
- return obtain(new ByteArrayInputStream(key.getBytes()));
- }
-
- /**
- * Obtain a Symm from 2048 key from a Stream
- *
- * @param is
- * @return
- * @throws IOException
- */
- public static Symm obtain(InputStream is) throws IOException {
- ByteArrayOutputStream baos = new ByteArrayOutputStream();
- try {
- base64url.decode(is, baos);
- } catch (IOException e) {
- // don't give clue
- throw new IOException("Invalid Key");
- }
- byte[] bkey = baos.toByteArray();
- if(bkey.length<0x88) { // 2048 bit key
- throw new IOException("Invalid key");
- }
- return baseCrypt().obtain(bkey);
- }
-
- /**
- * Convenience for picking up Keyfile
- *
- * @param f
- * @return
- * @throws IOException
- */
- public static Symm obtain(File f) throws IOException {
- FileInputStream fis = new FileInputStream(f);
- try {
- return obtain(fis);
- } finally {
- fis.close();
- }
- }
- /**
- * Decrypt into a String
- *
- * Convenience method
- *
- * @param password
- * @return
- * @throws IOException
- */
- public String enpass(String password) throws IOException {
- ByteArrayOutputStream baos = new ByteArrayOutputStream();
- enpass(password,baos);
- return new String(baos.toByteArray());
- }
-
- /**
- * Create an encrypted password, making sure that even short passwords have a minimum length.
- *
- * @param password
- * @param os
- * @throws IOException
- */
- public void enpass(final String password, final OutputStream os) throws IOException {
- final ByteArrayOutputStream baos = new ByteArrayOutputStream();
- DataOutputStream dos = new DataOutputStream(baos);
- byte[] bytes = password.getBytes();
- if(this.getClass().getSimpleName().startsWith("base64")) { // don't expose randomization
- dos.write(bytes);
- } else {
-
- Random r = new SecureRandom();
- int start = 0;
- byte b;
- for(int i=0;i<3;++i) {
- dos.writeByte(b=(byte)r.nextInt());
- start+=Math.abs(b);
- }
- start%=0x7;
- for(int i=0;i<start;++i) {
- dos.writeByte(r.nextInt());
- }
- dos.writeInt((int)System.currentTimeMillis());
- int minlength = Math.min(0x9,bytes.length);
- dos.writeByte(minlength); // expect truncation
- if(bytes.length<0x9) {
- for(int i=0;i<bytes.length;++i) {
- dos.writeByte(r.nextInt());
- dos.writeByte(bytes[i]);
- }
- // make sure it's long enough
- for(int i=bytes.length;i<0x9;++i) {
- dos.writeByte(r.nextInt());
- }
- } else {
- dos.write(bytes);
- }
- }
-
- // 7/21/2016 jg add AES Encryption to the mix
- exec(new AESExec() {
- @Override
- public void exec(AES aes) throws IOException {
- CipherInputStream cis = aes.inputStream(new ByteArrayInputStream(baos.toByteArray()), true);
- try {
- encode(cis,os);
- } finally {
- os.flush();
- cis.close();
- }
- }
- });
- synchronized(ENC) {
- }
- }
-
- /**
- * Decrypt a password into a String
- *
- * Convenience method
- *
- * @param password
- * @return
- * @throws IOException
- */
- public String depass(String password) throws IOException {
- if(password==null)return null;
- ByteArrayOutputStream baos = new ByteArrayOutputStream();
- depass(password,baos);
- return new String(baos.toByteArray());
- }
-
- /**
- * Decrypt a password
- *
- * Skip Symm.ENC
- *
- * @param password
- * @param os
- * @return
- * @throws IOException
- */
- public long depass(final String password, final OutputStream os) throws IOException {
- int offset = password.startsWith(ENC)?4:0;
- final ByteArrayOutputStream baos = new ByteArrayOutputStream();
- final ByteArrayInputStream bais = new ByteArrayInputStream(password.getBytes(),offset,password.length()-offset);
- exec(new AESExec() {
- @Override
- public void exec(AES aes) throws IOException {
- CipherOutputStream cos = aes.outputStream(baos, false);
- decode(bais,cos);
- cos.close(); // flush
- }
- });
- byte[] bytes = baos.toByteArray();
- DataInputStream dis = new DataInputStream(new ByteArrayInputStream(bytes));
- long time;
- if(this.getClass().getSimpleName().startsWith("base64")) { // don't expose randomization
- os.write(bytes);
- time = 0L;
- } else {
- int start=0;
- for(int i=0;i<3;++i) {
- start+=Math.abs(dis.readByte());
- }
- start%=0x7;
- for(int i=0;i<start;++i) {
- dis.readByte();
- }
- time = (dis.readInt() & 0xFFFF)|(System.currentTimeMillis()&0xFFFF0000);
- int minlength = dis.readByte();
- if(minlength<0x9){
- DataOutputStream dos = new DataOutputStream(os);
- for(int i=0;i<minlength;++i) {
- dis.readByte();
- dos.writeByte(dis.readByte());
- }
- } else {
- int pre =((Byte.SIZE*3+Integer.SIZE+Byte.SIZE)/Byte.SIZE)+start;
- os.write(bytes, pre, bytes.length-pre);
- }
- }
- return time;
- }
-
- public static String randomGen(int numBytes) {
- return randomGen(passChars,numBytes);
- }
-
- public static String randomGen(char[] chars ,int numBytes) {
- int rint;
- StringBuilder sb = new StringBuilder(numBytes);
- for(int i=0;i<numBytes;++i) {
- rint = random.nextInt(chars.length);
- sb.append(chars[rint]);
- }
- return sb.toString();
- }
- // Internal mechanism for helping to randomize placement of characters within a Symm codeset
- // Based on an incoming data stream (originally created randomly, but can be recreated within
- // 2048 key), go after a particular place in the new codeset. If that codeset spot is used, then move
- // right or left (depending on iteration) to find the next available slot. In this way, key generation
- // is speeded up by only enacting N iterations, but adds a spreading effect of the random number stream, so that keyset is also
- // shuffled for a good spread. It is, however, repeatable, given the same number set, allowing for
- // quick recreation when the official stream is actually obtained.
- public Symm obtain(byte[] key) throws IOException {
- try {
- byte[] bytes = new byte[AES.AES_KEY_SIZE/8];
- int offset = (Math.abs(key[(47%key.length)])+137)%(key.length-bytes.length);
- for(int i=0;i<bytes.length;++i) {
- bytes[i] = key[i+offset];
- }
-
- aes = new AES(bytes,0,bytes.length);
- } catch (Exception e) {
- throw new IOException(e);
- }
- int filled = codeset.length;
- char[] seq = new char[filled];
- int end = filled--;
-
- boolean right = true;
- int index;
- Obtain o = new Obtain(this,key);
-
- while(filled>=0) {
- index = o.next();
- if(index<0 || index>=codeset.length) {
- System.out.println("uh, oh");
- }
- if(right) { // alternate going left or right to find the next open slot (keeps it from taking too long to hit something)
- for(int j=index;j<end;++j) {
- if(seq[j]==0) {
- seq[j]=codeset[filled];
- --filled;
- break;
- }
- }
- right = false;
- } else {
- for(int j=index;j>=0;--j) {
- if(seq[j]==0) {
- seq[j]=codeset[filled];
- --filled;
- break;
- }
- }
- right = true;
- }
- }
- return new Symm(seq,this);
- }
-}