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Posted to dev@mina.apache.org by Emmanuel Lécharny <el...@gmail.com> on 2013/12/03 16:29:47 UTC

Re: git commit: [SSHD-259] Provide Base64 in sshd

Hi Guillaume,

any reason not to use the mina-core class instead of copying it in sshd ?


Le 12/3/13 3:43 PM, gnodet@apache.org a écrit :
> Updated Branches:
>   refs/heads/master 9a27e7284 -> 11415ce63
>
>
> [SSHD-259] Provide Base64 in sshd
>
> Project: http://git-wip-us.apache.org/repos/asf/mina-sshd/repo
> Commit: http://git-wip-us.apache.org/repos/asf/mina-sshd/commit/11415ce6
> Tree: http://git-wip-us.apache.org/repos/asf/mina-sshd/tree/11415ce6
> Diff: http://git-wip-us.apache.org/repos/asf/mina-sshd/diff/11415ce6
>
> Branch: refs/heads/master
> Commit: 11415ce63ff993c42a10e4a48f39092f6042a941
> Parents: 9a27e72
> Author: Guillaume Nodet <gn...@apache.org>
> Authored: Tue Dec 3 15:43:23 2013 +0100
> Committer: Guillaume Nodet <gn...@apache.org>
> Committed: Tue Dec 3 15:43:23 2013 +0100
>
> ----------------------------------------------------------------------
>  .../org/apache/sshd/common/util/Base64.java     | 491 +++++++++++++++++++
>  1 file changed, 491 insertions(+)
> ----------------------------------------------------------------------
>
>
> http://git-wip-us.apache.org/repos/asf/mina-sshd/blob/11415ce6/sshd-core/src/main/java/org/apache/sshd/common/util/Base64.java
> ----------------------------------------------------------------------
> diff --git a/sshd-core/src/main/java/org/apache/sshd/common/util/Base64.java b/sshd-core/src/main/java/org/apache/sshd/common/util/Base64.java
> new file mode 100644
> index 0000000..ffc476c
> --- /dev/null
> +++ b/sshd-core/src/main/java/org/apache/sshd/common/util/Base64.java
> @@ -0,0 +1,491 @@
> +/*
> + *  Licensed to the Apache Software Foundation (ASF) under one
> + *  or more contributor license agreements.  See the NOTICE file
> + *  distributed with this work for additional information
> + *  regarding copyright ownership.  The ASF licenses this file
> + *  to you 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.
> + *
> + */
> +package org.apache.sshd.common.util;
> +
> +import java.security.InvalidParameterException;
> +
> +/**
> + * Provides Base64 encoding and decoding as defined by RFC 2045.
> + *
> + * <p>This class implements section <cite>6.8. Base64 Content-Transfer-Encoding</cite> 
> + * from RFC 2045 <cite>Multipurpose Internet Mail Extensions (MIME) Part One: 
> + * Format of Internet Message Bodies</cite> by Freed and Borenstein.</p> 
> + *
> + * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>
> + *
> + *  This class was 
> + * @author Apache Software Foundation commons codec (http://commons.apache.org/codec/)
> + * @author <a href="http://mina.apache.org">Apache MINA Project</a>
> + */
> +public class Base64 {
> +
> +    /**
> +     * Chunk size per RFC 2045 section 6.8.
> +     *
> +     * <p>The {@value} character limit does not count the trailing CRLF, but counts 
> +     * all other characters, including any equal signs.</p>
> +     *
> +     * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 6.8</a>
> +     */
> +    static final int CHUNK_SIZE = 76;
> +
> +    /**
> +     * Chunk separator per RFC 2045 section 2.1.
> +     *
> +     * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 2.1</a>
> +     */
> +    static final byte[] CHUNK_SEPARATOR = "\r\n".getBytes();
> +
> +    /**
> +     * The base length.
> +     */
> +    static final int BASELENGTH = 255;
> +
> +    /**
> +     * Lookup length.
> +     */
> +    static final int LOOKUPLENGTH = 64;
> +
> +    /**
> +     * Used to calculate the number of bits in a byte.
> +     */
> +    static final int EIGHTBIT = 8;
> +
> +    /**
> +     * Used when encoding something which has fewer than 24 bits.
> +     */
> +    static final int SIXTEENBIT = 16;
> +
> +    /**
> +     * Used to determine how many bits data contains.
> +     */
> +    static final int TWENTYFOURBITGROUP = 24;
> +
> +    /**
> +     * Used to get the number of Quadruples.
> +     */
> +    static final int FOURBYTE = 4;
> +
> +    /**
> +     * Used to test the sign of a byte.
> +     */
> +    static final int SIGN = -128;
> +
> +    /**
> +     * Byte used to pad output.
> +     */
> +    static final byte PAD = (byte) '=';
> +
> +    // Create arrays to hold the base64 characters and a 
> +    // lookup for base64 chars
> +    private static byte[] base64Alphabet = new byte[BASELENGTH];
> +
> +    private static byte[] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
> +
> +    // Populating the lookup and character arrays
> +    static {
> +        for (int i = 0; i < BASELENGTH; i++) {
> +            base64Alphabet[i] = (byte) -1;
> +        }
> +        for (int i = 'Z'; i >= 'A'; i--) {
> +            base64Alphabet[i] = (byte) (i - 'A');
> +        }
> +        for (int i = 'z'; i >= 'a'; i--) {
> +            base64Alphabet[i] = (byte) (i - 'a' + 26);
> +        }
> +        for (int i = '9'; i >= '0'; i--) {
> +            base64Alphabet[i] = (byte) (i - '0' + 52);
> +        }
> +
> +        base64Alphabet['+'] = 62;
> +        base64Alphabet['/'] = 63;
> +
> +        for (int i = 0; i <= 25; i++) {
> +            lookUpBase64Alphabet[i] = (byte) ('A' + i);
> +        }
> +
> +        for (int i = 26, j = 0; i <= 51; i++, j++) {
> +            lookUpBase64Alphabet[i] = (byte) ('a' + j);
> +        }
> +
> +        for (int i = 52, j = 0; i <= 61; i++, j++) {
> +            lookUpBase64Alphabet[i] = (byte) ('0' + j);
> +        }
> +
> +        lookUpBase64Alphabet[62] = (byte) '+';
> +        lookUpBase64Alphabet[63] = (byte) '/';
> +    }
> +
> +    private static boolean isBase64(byte octect) {
> +        if (octect == PAD) {
> +            return true;
> +        } else if (base64Alphabet[octect] == -1) {
> +            return false;
> +        } else {
> +            return true;
> +        }
> +    }
> +
> +    /**
> +     * Tests a given byte array to see if it contains
> +     * only valid characters within the Base64 alphabet.
> +     *
> +     * @param arrayOctect byte array to test
> +     * @return true if all bytes are valid characters in the Base64
> +     *         alphabet or if the byte array is empty; false, otherwise
> +     */
> +    public static boolean isArrayByteBase64(byte[] arrayOctect) {
> +
> +        arrayOctect = discardWhitespace(arrayOctect);
> +
> +        int length = arrayOctect.length;
> +        if (length == 0) {
> +            // shouldn't a 0 length array be valid base64 data?
> +            return true;
> +        }
> +        for (int i = 0; i < length; i++) {
> +            if (!isBase64(arrayOctect[i])) {
> +                return false;
> +            }
> +        }
> +        return true;
> +    }
> +
> +    /**
> +     * Encodes binary data using the base64 algorithm but
> +     * does not chunk the output.
> +     *
> +     * @param binaryData binary data to encode
> +     * @return Base64 characters
> +     */
> +    public static byte[] encodeBase64(byte[] binaryData) {
> +        return encodeBase64(binaryData, false);
> +    }
> +
> +    /**
> +     * Encodes binary data using the base64 algorithm and chunks
> +     * the encoded output into 76 character blocks
> +     *
> +     * @param binaryData binary data to encode
> +     * @return Base64 characters chunked in 76 character blocks
> +     */
> +    public static byte[] encodeBase64Chunked(byte[] binaryData) {
> +        return encodeBase64(binaryData, true);
> +    }
> +
> +    /**
> +     * Decodes an Object using the base64 algorithm.  This method
> +     * is provided in order to satisfy the requirements of the
> +     * Decoder interface, and will throw a DecoderException if the
> +     * supplied object is not of type byte[].
> +     *
> +     * @param pObject Object to decode
> +     * @return An object (of type byte[]) containing the 
> +     *         binary data which corresponds to the byte[] supplied.
> +     * @throws InvalidParameterException if the parameter supplied is not
> +     *                          of type byte[]
> +     */
> +    public Object decode(Object pObject) {
> +        if (!(pObject instanceof byte[])) {
> +            throw new InvalidParameterException("Parameter supplied to Base64 decode is not a byte[]");
> +        }
> +        return decode((byte[]) pObject);
> +    }
> +
> +    /**
> +     * Decodes a byte[] containing containing
> +     * characters in the Base64 alphabet.
> +     *
> +     * @param pArray A byte array containing Base64 character data
> +     * @return a byte array containing binary data
> +     */
> +    public byte[] decode(byte[] pArray) {
> +        return decodeBase64(pArray);
> +    }
> +
> +    /**
> +     * Encodes binary data using the base64 algorithm, optionally
> +     * chunking the output into 76 character blocks.
> +     *
> +     * @param binaryData Array containing binary data to encode.
> +     * @param isChunked if isChunked is true this encoder will chunk
> +     *                  the base64 output into 76 character blocks
> +     * @return Base64-encoded data.
> +     */
> +    public static byte[] encodeBase64(byte[] binaryData, boolean isChunked) {
> +        int lengthDataBits = binaryData.length * EIGHTBIT;
> +        int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
> +        int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
> +        byte encodedData[] = null;
> +        int encodedDataLength = 0;
> +        int nbrChunks = 0;
> +
> +        if (fewerThan24bits != 0) {
> +            //data not divisible by 24 bit
> +            encodedDataLength = (numberTriplets + 1) * 4;
> +        } else {
> +            // 16 or 8 bit
> +            encodedDataLength = numberTriplets * 4;
> +        }
> +
> +        // If the output is to be "chunked" into 76 character sections, 
> +        // for compliance with RFC 2045 MIME, then it is important to 
> +        // allow for extra length to account for the separator(s)
> +        if (isChunked) {
> +
> +            nbrChunks = (CHUNK_SEPARATOR.length == 0 ? 0 : (int) Math.ceil((float) encodedDataLength / CHUNK_SIZE));
> +            encodedDataLength += nbrChunks * CHUNK_SEPARATOR.length;
> +        }
> +
> +        encodedData = new byte[encodedDataLength];
> +
> +        byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
> +
> +        int encodedIndex = 0;
> +        int dataIndex = 0;
> +        int i = 0;
> +        int nextSeparatorIndex = CHUNK_SIZE;
> +        int chunksSoFar = 0;
> +
> +        for (i = 0; i < numberTriplets; i++) {
> +            dataIndex = i * 3;
> +            b1 = binaryData[dataIndex];
> +            b2 = binaryData[dataIndex + 1];
> +            b3 = binaryData[dataIndex + 2];
> +
> +            l = (byte) (b2 & 0x0f);
> +            k = (byte) (b1 & 0x03);
> +
> +            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
> +            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
> +            byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);
> +
> +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
> +            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[val2 | (k << 4)];
> +            encodedData[encodedIndex + 2] = lookUpBase64Alphabet[(l << 2) | val3];
> +            encodedData[encodedIndex + 3] = lookUpBase64Alphabet[b3 & 0x3f];
> +
> +            encodedIndex += 4;
> +
> +            // If we are chunking, let's put a chunk separator down.
> +            if (isChunked) {
> +                // this assumes that CHUNK_SIZE % 4 == 0
> +                if (encodedIndex == nextSeparatorIndex) {
> +                    System.arraycopy(CHUNK_SEPARATOR, 0, encodedData, encodedIndex, CHUNK_SEPARATOR.length);
> +                    chunksSoFar++;
> +                    nextSeparatorIndex = (CHUNK_SIZE * (chunksSoFar + 1)) + (chunksSoFar * CHUNK_SEPARATOR.length);
> +                    encodedIndex += CHUNK_SEPARATOR.length;
> +                }
> +            }
> +        }
> +
> +        // form integral number of 6-bit groups
> +        dataIndex = i * 3;
> +
> +        if (fewerThan24bits == EIGHTBIT) {
> +            b1 = binaryData[dataIndex];
> +            k = (byte) (b1 & 0x03);
> +            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
> +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
> +            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[k << 4];
> +            encodedData[encodedIndex + 2] = PAD;
> +            encodedData[encodedIndex + 3] = PAD;
> +        } else if (fewerThan24bits == SIXTEENBIT) {
> +
> +            b1 = binaryData[dataIndex];
> +            b2 = binaryData[dataIndex + 1];
> +            l = (byte) (b2 & 0x0f);
> +            k = (byte) (b1 & 0x03);
> +
> +            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
> +            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
> +
> +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
> +            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[val2 | (k << 4)];
> +            encodedData[encodedIndex + 2] = lookUpBase64Alphabet[l << 2];
> +            encodedData[encodedIndex + 3] = PAD;
> +        }
> +
> +        if (isChunked) {
> +            // we also add a separator to the end of the final chunk.
> +            if (chunksSoFar < nbrChunks) {
> +                System.arraycopy(CHUNK_SEPARATOR, 0, encodedData, encodedDataLength - CHUNK_SEPARATOR.length,
> +                        CHUNK_SEPARATOR.length);
> +            }
> +        }
> +
> +        return encodedData;
> +    }
> +
> +    /**
> +     * Decodes Base64 data into octects
> +     *
> +     * @param base64Data Byte array containing Base64 data
> +     * @return Array containing decoded data.
> +     */
> +    public static byte[] decodeBase64(byte[] base64Data) {
> +        // RFC 2045 requires that we discard ALL non-Base64 characters
> +        base64Data = discardNonBase64(base64Data);
> +
> +        // handle the edge case, so we don't have to worry about it later
> +        if (base64Data.length == 0) {
> +            return new byte[0];
> +        }
> +
> +        int numberQuadruple = base64Data.length / FOURBYTE;
> +        byte decodedData[] = null;
> +        byte b1 = 0, b2 = 0, b3 = 0, b4 = 0, marker0 = 0, marker1 = 0;
> +
> +        // Throw away anything not in base64Data
> +
> +        int encodedIndex = 0;
> +        int dataIndex = 0;
> +        {
> +            // this sizes the output array properly - rlw
> +            int lastData = base64Data.length;
> +            // ignore the '=' padding
> +            while (base64Data[lastData - 1] == PAD) {
> +                if (--lastData == 0) {
> +                    return new byte[0];
> +                }
> +            }
> +            decodedData = new byte[lastData - numberQuadruple];
> +        }
> +
> +        for (int i = 0; i < numberQuadruple; i++) {
> +            dataIndex = i * 4;
> +            marker0 = base64Data[dataIndex + 2];
> +            marker1 = base64Data[dataIndex + 3];
> +
> +            b1 = base64Alphabet[base64Data[dataIndex]];
> +            b2 = base64Alphabet[base64Data[dataIndex + 1]];
> +
> +            if (marker0 != PAD && marker1 != PAD) {
> +                //No PAD e.g 3cQl
> +                b3 = base64Alphabet[marker0];
> +                b4 = base64Alphabet[marker1];
> +
> +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
> +                decodedData[encodedIndex + 1] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
> +                decodedData[encodedIndex + 2] = (byte) (b3 << 6 | b4);
> +            } else if (marker0 == PAD) {
> +                //Two PAD e.g. 3c[Pad][Pad]
> +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
> +            } else if (marker1 == PAD) {
> +                //One PAD e.g. 3cQ[Pad]
> +                b3 = base64Alphabet[marker0];
> +
> +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
> +                decodedData[encodedIndex + 1] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
> +            }
> +            encodedIndex += 3;
> +        }
> +        return decodedData;
> +    }
> +
> +    /**
> +     * Discards any whitespace from a base-64 encoded block.
> +     *
> +     * @param data The base-64 encoded data to discard the whitespace
> +     * from.
> +     * @return The data, less whitespace (see RFC 2045).
> +     */
> +    static byte[] discardWhitespace(byte[] data) {
> +        byte groomedData[] = new byte[data.length];
> +        int bytesCopied = 0;
> +
> +        for (int i = 0; i < data.length; i++) {
> +            switch (data[i]) {
> +                case (byte) ' ':
> +                case (byte) '\n':
> +                case (byte) '\r':
> +                case (byte) '\t':
> +                    break;
> +                default:
> +                    groomedData[bytesCopied++] = data[i];
> +            }
> +        }
> +
> +        byte packedData[] = new byte[bytesCopied];
> +
> +        System.arraycopy(groomedData, 0, packedData, 0, bytesCopied);
> +
> +        return packedData;
> +    }
> +
> +    /**
> +     * Discards any characters outside of the base64 alphabet, per
> +     * the requirements on page 25 of RFC 2045 - "Any characters
> +     * outside of the base64 alphabet are to be ignored in base64
> +     * encoded data."
> +     *
> +     * @param data The base-64 encoded data to groom
> +     * @return The data, less non-base64 characters (see RFC 2045).
> +     */
> +    static byte[] discardNonBase64(byte[] data) {
> +        byte groomedData[] = new byte[data.length];
> +        int bytesCopied = 0;
> +
> +        for (int i = 0; i < data.length; i++) {
> +            if (isBase64(data[i])) {
> +                groomedData[bytesCopied++] = data[i];
> +            }
> +        }
> +
> +        byte packedData[] = new byte[bytesCopied];
> +
> +        System.arraycopy(groomedData, 0, packedData, 0, bytesCopied);
> +
> +        return packedData;
> +    }
> +
> +    // Implementation of the Encoder Interface
> +
> +    /**
> +     * Encodes an Object using the base64 algorithm.  This method
> +     * is provided in order to satisfy the requirements of the
> +     * Encoder interface, and will throw an EncoderException if the
> +     * supplied object is not of type byte[].
> +     *
> +     * @param pObject Object to encode
> +     * @return An object (of type byte[]) containing the 
> +     *         base64 encoded data which corresponds to the byte[] supplied.
> +     * @throws InvalidParameterException if the parameter supplied is not
> +     *                          of type byte[]
> +     */
> +    public Object encode(Object pObject) {
> +        if (!(pObject instanceof byte[])) {
> +            throw new InvalidParameterException("Parameter supplied to Base64 encode is not a byte[]");
> +        }
> +        return encode((byte[]) pObject);
> +    }
> +
> +    /**
> +     * Encodes a byte[] containing binary data, into a byte[] containing
> +     * characters in the Base64 alphabet.
> +     *
> +     * @param pArray a byte array containing binary data
> +     * @return A byte array containing only Base64 character data
> +     */
> +    public byte[] encode(byte[] pArray) {
> +        return encodeBase64(pArray, false);
> +    }
> +
> +}
> \ No newline at end of file
>


-- 
Regards,
Cordialement,
Emmanuel Lécharny
www.iktek.com 


Re: git commit: [SSHD-259] Provide Base64 in sshd

Posted by Emmanuel Lécharny <el...@gmail.com>.
Le 12/3/13 4:29 PM, Emmanuel Lécharny a écrit :
> Hi Guillaume,
>
> any reason not to use the mina-core class instead of copying it in sshd ?

Sorry, just read SSHD-259. So it makes sense...


-- 
Regards,
Cordialement,
Emmanuel Lécharny
www.iktek.com