Base64.java
- /*
- * 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.commons.codec.binary;
- import java.math.BigInteger;
- /**
- * Provides Base64 encoding and decoding as defined by <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>.
- *
- * <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>
- * <p>
- * The class can be parameterized in the following manner with various constructors:
- * </p>
- * <ul>
- * <li>URL-safe mode: Default off.</li>
- * <li>Line length: Default 76. Line length that aren't multiples of 4 will still essentially end up being multiples of
- * 4 in the encoded data.
- * <li>Line separator: Default is CRLF ("\r\n")</li>
- * </ul>
- * <p>
- * The URL-safe parameter is only applied to encode operations. Decoding seamlessly handles both modes.
- * </p>
- * <p>
- * Since this class operates directly on byte streams, and not character streams, it is hard-coded to only
- * encode/decode character encodings which are compatible with the lower 127 ASCII chart (ISO-8859-1, Windows-1252,
- * UTF-8, etc).
- * </p>
- * <p>
- * This class is thread-safe.
- * </p>
- *
- * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>
- * @since 1.0
- * @version $Id: Base64.java 1789158 2017-03-28 15:04:58Z sebb $
- */
- public class Base64 extends BaseNCodec {
- /**
- * BASE32 characters are 6 bits in length.
- * They are formed by taking a block of 3 octets to form a 24-bit string,
- * which is converted into 4 BASE64 characters.
- */
- private static final int BITS_PER_ENCODED_BYTE = 6;
- private static final int BYTES_PER_UNENCODED_BLOCK = 3;
- private static final int BYTES_PER_ENCODED_BLOCK = 4;
- /**
- * Chunk separator per RFC 2045 section 2.1.
- *
- * <p>
- * N.B. The next major release may break compatibility and make this field private.
- * </p>
- *
- * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 2.1</a>
- */
- static final byte[] CHUNK_SEPARATOR = {'\r', '\n'};
- /**
- * This array is a lookup table that translates 6-bit positive integer index values into their "Base64 Alphabet"
- * equivalents as specified in Table 1 of RFC 2045.
- *
- * Thanks to "commons" project in ws.apache.org for this code.
- * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
- */
- private static final byte[] STANDARD_ENCODE_TABLE = {
- 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
- 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
- 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
- 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
- '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
- };
- /**
- * This is a copy of the STANDARD_ENCODE_TABLE above, but with + and /
- * changed to - and _ to make the encoded Base64 results more URL-SAFE.
- * This table is only used when the Base64's mode is set to URL-SAFE.
- */
- private static final byte[] URL_SAFE_ENCODE_TABLE = {
- 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
- 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
- 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
- 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
- '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '-', '_'
- };
- /**
- * This array is a lookup table that translates Unicode characters drawn from the "Base64 Alphabet" (as specified
- * in Table 1 of RFC 2045) into their 6-bit positive integer equivalents. Characters that are not in the Base64
- * alphabet but fall within the bounds of the array are translated to -1.
- *
- * Note: '+' and '-' both decode to 62. '/' and '_' both decode to 63. This means decoder seamlessly handles both
- * URL_SAFE and STANDARD base64. (The encoder, on the other hand, needs to know ahead of time what to emit).
- *
- * Thanks to "commons" project in ws.apache.org for this code.
- * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
- */
- private static final byte[] DECODE_TABLE = {
- // 0 1 2 3 4 5 6 7 8 9 A B C D E F
- -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 00-0f
- -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 10-1f
- -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, 62, -1, 63, // 20-2f + - /
- 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, // 30-3f 0-9
- -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, // 40-4f A-O
- 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, 63, // 50-5f P-Z _
- -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, // 60-6f a-o
- 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 // 70-7a p-z
- };
- /**
- * Base64 uses 6-bit fields.
- */
- /** Mask used to extract 6 bits, used when encoding */
- private static final int MASK_6BITS = 0x3f;
- // The static final fields above are used for the original static byte[] methods on Base64.
- // The private member fields below are used with the new streaming approach, which requires
- // some state be preserved between calls of encode() and decode().
- /**
- * Encode table to use: either STANDARD or URL_SAFE. Note: the DECODE_TABLE above remains static because it is able
- * to decode both STANDARD and URL_SAFE streams, but the encodeTable must be a member variable so we can switch
- * between the two modes.
- */
- private final byte[] encodeTable;
- // Only one decode table currently; keep for consistency with Base32 code
- private final byte[] decodeTable = DECODE_TABLE;
- /**
- * Line separator for encoding. Not used when decoding. Only used if lineLength > 0.
- */
- private final byte[] lineSeparator;
- /**
- * Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
- * <code>decodeSize = 3 + lineSeparator.length;</code>
- */
- private final int decodeSize;
- /**
- * Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
- * <code>encodeSize = 4 + lineSeparator.length;</code>
- */
- private final int encodeSize;
- /**
- * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
- * <p>
- * When encoding the line length is 0 (no chunking), and the encoding table is STANDARD_ENCODE_TABLE.
- * </p>
- *
- * <p>
- * When decoding all variants are supported.
- * </p>
- */
- public Base64() {
- this(0);
- }
- /**
- * Creates a Base64 codec used for decoding (all modes) and encoding in the given URL-safe mode.
- * <p>
- * When encoding the line length is 76, the line separator is CRLF, and the encoding table is STANDARD_ENCODE_TABLE.
- * </p>
- *
- * <p>
- * When decoding all variants are supported.
- * </p>
- *
- * @param urlSafe
- * if <code>true</code>, URL-safe encoding is used. In most cases this should be set to
- * <code>false</code>.
- * @since 1.4
- */
- public Base64(final boolean urlSafe) {
- this(MIME_CHUNK_SIZE, CHUNK_SEPARATOR, urlSafe);
- }
- /**
- * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
- * <p>
- * When encoding the line length is given in the constructor, the line separator is CRLF, and the encoding table is
- * STANDARD_ENCODE_TABLE.
- * </p>
- * <p>
- * Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
- * </p>
- * <p>
- * When decoding all variants are supported.
- * </p>
- *
- * @param lineLength
- * Each line of encoded data will be at most of the given length (rounded down to nearest multiple of
- * 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when
- * decoding.
- * @since 1.4
- */
- public Base64(final int lineLength) {
- this(lineLength, CHUNK_SEPARATOR);
- }
- /**
- * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
- * <p>
- * When encoding the line length and line separator are given in the constructor, and the encoding table is
- * STANDARD_ENCODE_TABLE.
- * </p>
- * <p>
- * Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
- * </p>
- * <p>
- * When decoding all variants are supported.
- * </p>
- *
- * @param lineLength
- * Each line of encoded data will be at most of the given length (rounded down to nearest multiple of
- * 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when
- * decoding.
- * @param lineSeparator
- * Each line of encoded data will end with this sequence of bytes.
- * @throws IllegalArgumentException
- * Thrown when the provided lineSeparator included some base64 characters.
- * @since 1.4
- */
- public Base64(final int lineLength, final byte[] lineSeparator) {
- this(lineLength, lineSeparator, false);
- }
- /**
- * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
- * <p>
- * When encoding the line length and line separator are given in the constructor, and the encoding table is
- * STANDARD_ENCODE_TABLE.
- * </p>
- * <p>
- * Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
- * </p>
- * <p>
- * When decoding all variants are supported.
- * </p>
- *
- * @param lineLength
- * Each line of encoded data will be at most of the given length (rounded down to nearest multiple of
- * 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when
- * decoding.
- * @param lineSeparator
- * Each line of encoded data will end with this sequence of bytes.
- * @param urlSafe
- * Instead of emitting '+' and '/' we emit '-' and '_' respectively. urlSafe is only applied to encode
- * operations. Decoding seamlessly handles both modes.
- * <b>Note: no padding is added when using the URL-safe alphabet.</b>
- * @throws IllegalArgumentException
- * The provided lineSeparator included some base64 characters. That's not going to work!
- * @since 1.4
- */
- public Base64(final int lineLength, final byte[] lineSeparator, final boolean urlSafe) {
- super(BYTES_PER_UNENCODED_BLOCK, BYTES_PER_ENCODED_BLOCK,
- lineLength,
- lineSeparator == null ? 0 : lineSeparator.length);
- // TODO could be simplified if there is no requirement to reject invalid line sep when length <=0
- // @see test case Base64Test.testConstructors()
- if (lineSeparator != null) {
- if (containsAlphabetOrPad(lineSeparator)) {
- final String sep = StringUtils.newStringUtf8(lineSeparator);
- throw new IllegalArgumentException("lineSeparator must not contain base64 characters: [" + sep + "]");
- }
- if (lineLength > 0){ // null line-sep forces no chunking rather than throwing IAE
- this.encodeSize = BYTES_PER_ENCODED_BLOCK + lineSeparator.length;
- this.lineSeparator = new byte[lineSeparator.length];
- System.arraycopy(lineSeparator, 0, this.lineSeparator, 0, lineSeparator.length);
- } else {
- this.encodeSize = BYTES_PER_ENCODED_BLOCK;
- this.lineSeparator = null;
- }
- } else {
- this.encodeSize = BYTES_PER_ENCODED_BLOCK;
- this.lineSeparator = null;
- }
- this.decodeSize = this.encodeSize - 1;
- this.encodeTable = urlSafe ? URL_SAFE_ENCODE_TABLE : STANDARD_ENCODE_TABLE;
- }
- /**
- * Returns our current encode mode. True if we're URL-SAFE, false otherwise.
- *
- * @return true if we're in URL-SAFE mode, false otherwise.
- * @since 1.4
- */
- public boolean isUrlSafe() {
- return this.encodeTable == URL_SAFE_ENCODE_TABLE;
- }
- /**
- * <p>
- * Encodes all of the provided data, starting at inPos, for inAvail bytes. Must be called at least twice: once with
- * the data to encode, and once with inAvail set to "-1" to alert encoder that EOF has been reached, to flush last
- * remaining bytes (if not multiple of 3).
- * </p>
- * <p><b>Note: no padding is added when encoding using the URL-safe alphabet.</b></p>
- * <p>
- * Thanks to "commons" project in ws.apache.org for the bitwise operations, and general approach.
- * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
- * </p>
- *
- * @param in
- * byte[] array of binary data to base64 encode.
- * @param inPos
- * Position to start reading data from.
- * @param inAvail
- * Amount of bytes available from input for encoding.
- * @param context
- * the context to be used
- */
- @Override
- void encode(final byte[] in, int inPos, final int inAvail, final Context context) {
- if (context.eof) {
- return;
- }
- // inAvail < 0 is how we're informed of EOF in the underlying data we're
- // encoding.
- if (inAvail < 0) {
- context.eof = true;
- if (0 == context.modulus && lineLength == 0) {
- return; // no leftovers to process and not using chunking
- }
- final byte[] buffer = ensureBufferSize(encodeSize, context);
- final int savedPos = context.pos;
- switch (context.modulus) { // 0-2
- case 0 : // nothing to do here
- break;
- case 1 : // 8 bits = 6 + 2
- // top 6 bits:
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 2) & MASK_6BITS];
- // remaining 2:
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea << 4) & MASK_6BITS];
- // URL-SAFE skips the padding to further reduce size.
- if (encodeTable == STANDARD_ENCODE_TABLE) {
- buffer[context.pos++] = pad;
- buffer[context.pos++] = pad;
- }
- break;
- case 2 : // 16 bits = 6 + 6 + 4
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 10) & MASK_6BITS];
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 4) & MASK_6BITS];
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea << 2) & MASK_6BITS];
- // URL-SAFE skips the padding to further reduce size.
- if (encodeTable == STANDARD_ENCODE_TABLE) {
- buffer[context.pos++] = pad;
- }
- break;
- default:
- throw new IllegalStateException("Impossible modulus "+context.modulus);
- }
- context.currentLinePos += context.pos - savedPos; // keep track of current line position
- // if currentPos == 0 we are at the start of a line, so don't add CRLF
- if (lineLength > 0 && context.currentLinePos > 0) {
- System.arraycopy(lineSeparator, 0, buffer, context.pos, lineSeparator.length);
- context.pos += lineSeparator.length;
- }
- } else {
- for (int i = 0; i < inAvail; i++) {
- final byte[] buffer = ensureBufferSize(encodeSize, context);
- context.modulus = (context.modulus+1) % BYTES_PER_UNENCODED_BLOCK;
- int b = in[inPos++];
- if (b < 0) {
- b += 256;
- }
- context.ibitWorkArea = (context.ibitWorkArea << 8) + b; // BITS_PER_BYTE
- if (0 == context.modulus) { // 3 bytes = 24 bits = 4 * 6 bits to extract
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 18) & MASK_6BITS];
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 12) & MASK_6BITS];
- buffer[context.pos++] = encodeTable[(context.ibitWorkArea >> 6) & MASK_6BITS];
- buffer[context.pos++] = encodeTable[context.ibitWorkArea & MASK_6BITS];
- context.currentLinePos += BYTES_PER_ENCODED_BLOCK;
- if (lineLength > 0 && lineLength <= context.currentLinePos) {
- System.arraycopy(lineSeparator, 0, buffer, context.pos, lineSeparator.length);
- context.pos += lineSeparator.length;
- context.currentLinePos = 0;
- }
- }
- }
- }
- }
- /**
- * <p>
- * Decodes all of the provided data, starting at inPos, for inAvail bytes. Should be called at least twice: once
- * with the data to decode, and once with inAvail set to "-1" to alert decoder that EOF has been reached. The "-1"
- * call is not necessary when decoding, but it doesn't hurt, either.
- * </p>
- * <p>
- * Ignores all non-base64 characters. This is how chunked (e.g. 76 character) data is handled, since CR and LF are
- * silently ignored, but has implications for other bytes, too. This method subscribes to the garbage-in,
- * garbage-out philosophy: it will not check the provided data for validity.
- * </p>
- * <p>
- * Thanks to "commons" project in ws.apache.org for the bitwise operations, and general approach.
- * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
- * </p>
- *
- * @param in
- * byte[] array of ascii data to base64 decode.
- * @param inPos
- * Position to start reading data from.
- * @param inAvail
- * Amount of bytes available from input for encoding.
- * @param context
- * the context to be used
- */
- @Override
- void decode(final byte[] in, int inPos, final int inAvail, final Context context) {
- if (context.eof) {
- return;
- }
- if (inAvail < 0) {
- context.eof = true;
- }
- for (int i = 0; i < inAvail; i++) {
- final byte[] buffer = ensureBufferSize(decodeSize, context);
- final byte b = in[inPos++];
- if (b == pad) {
- // We're done.
- context.eof = true;
- break;
- }
- if (b >= 0 && b < DECODE_TABLE.length) {
- final int result = DECODE_TABLE[b];
- if (result >= 0) {
- context.modulus = (context.modulus+1) % BYTES_PER_ENCODED_BLOCK;
- context.ibitWorkArea = (context.ibitWorkArea << BITS_PER_ENCODED_BYTE) + result;
- if (context.modulus == 0) {
- buffer[context.pos++] = (byte) ((context.ibitWorkArea >> 16) & MASK_8BITS);
- buffer[context.pos++] = (byte) ((context.ibitWorkArea >> 8) & MASK_8BITS);
- buffer[context.pos++] = (byte) (context.ibitWorkArea & MASK_8BITS);
- }
- }
- }
- }
- // Two forms of EOF as far as base64 decoder is concerned: actual
- // EOF (-1) and first time '=' character is encountered in stream.
- // This approach makes the '=' padding characters completely optional.
- if (context.eof && context.modulus != 0) {
- final byte[] buffer = ensureBufferSize(decodeSize, context);
- // We have some spare bits remaining
- // Output all whole multiples of 8 bits and ignore the rest
- switch (context.modulus) {
- // case 0 : // impossible, as excluded above
- case 1 : // 6 bits - ignore entirely
- // TODO not currently tested; perhaps it is impossible?
- break;
- case 2 : // 12 bits = 8 + 4
- context.ibitWorkArea = context.ibitWorkArea >> 4; // dump the extra 4 bits
- buffer[context.pos++] = (byte) ((context.ibitWorkArea) & MASK_8BITS);
- break;
- case 3 : // 18 bits = 8 + 8 + 2
- context.ibitWorkArea = context.ibitWorkArea >> 2; // dump 2 bits
- buffer[context.pos++] = (byte) ((context.ibitWorkArea >> 8) & MASK_8BITS);
- buffer[context.pos++] = (byte) ((context.ibitWorkArea) & MASK_8BITS);
- break;
- default:
- throw new IllegalStateException("Impossible modulus "+context.modulus);
- }
- }
- }
- /**
- * Tests a given byte array to see if it contains only valid characters within the Base64 alphabet. Currently the
- * method treats whitespace as valid.
- *
- * @param arrayOctet
- * byte array to test
- * @return <code>true</code> if all bytes are valid characters in the Base64 alphabet or if the byte array is empty;
- * <code>false</code>, otherwise
- * @deprecated 1.5 Use {@link #isBase64(byte[])}, will be removed in 2.0.
- */
- @Deprecated
- public static boolean isArrayByteBase64(final byte[] arrayOctet) {
- return isBase64(arrayOctet);
- }
- /**
- * Returns whether or not the <code>octet</code> is in the base 64 alphabet.
- *
- * @param octet
- * The value to test
- * @return <code>true</code> if the value is defined in the the base 64 alphabet, <code>false</code> otherwise.
- * @since 1.4
- */
- public static boolean isBase64(final byte octet) {
- return octet == PAD_DEFAULT || (octet >= 0 && octet < DECODE_TABLE.length && DECODE_TABLE[octet] != -1);
- }
- /**
- * Tests a given String to see if it contains only valid characters within the Base64 alphabet. Currently the
- * method treats whitespace as valid.
- *
- * @param base64
- * String to test
- * @return <code>true</code> if all characters in the String are valid characters in the Base64 alphabet or if
- * the String is empty; <code>false</code>, otherwise
- * @since 1.5
- */
- public static boolean isBase64(final String base64) {
- return isBase64(StringUtils.getBytesUtf8(base64));
- }
- /**
- * Tests a given byte array to see if it contains only valid characters within the Base64 alphabet. Currently the
- * method treats whitespace as valid.
- *
- * @param arrayOctet
- * byte array to test
- * @return <code>true</code> if all bytes are valid characters in the Base64 alphabet or if the byte array is empty;
- * <code>false</code>, otherwise
- * @since 1.5
- */
- public static boolean isBase64(final byte[] arrayOctet) {
- for (int i = 0; i < arrayOctet.length; i++) {
- if (!isBase64(arrayOctet[i]) && !isWhiteSpace(arrayOctet[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 byte[] containing Base64 characters in their UTF-8 representation.
- */
- public static byte[] encodeBase64(final byte[] binaryData) {
- return encodeBase64(binaryData, false);
- }
- /**
- * Encodes binary data using the base64 algorithm but does not chunk the output.
- *
- * NOTE: We changed the behaviour of this method from multi-line chunking (commons-codec-1.4) to
- * single-line non-chunking (commons-codec-1.5).
- *
- * @param binaryData
- * binary data to encode
- * @return String containing Base64 characters.
- * @since 1.4 (NOTE: 1.4 chunked the output, whereas 1.5 does not).
- */
- public static String encodeBase64String(final byte[] binaryData) {
- return StringUtils.newStringUsAscii(encodeBase64(binaryData, false));
- }
- /**
- * Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output. The
- * url-safe variation emits - and _ instead of + and / characters.
- * <b>Note: no padding is added.</b>
- * @param binaryData
- * binary data to encode
- * @return byte[] containing Base64 characters in their UTF-8 representation.
- * @since 1.4
- */
- public static byte[] encodeBase64URLSafe(final byte[] binaryData) {
- return encodeBase64(binaryData, false, true);
- }
- /**
- * Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output. The
- * url-safe variation emits - and _ instead of + and / characters.
- * <b>Note: no padding is added.</b>
- * @param binaryData
- * binary data to encode
- * @return String containing Base64 characters
- * @since 1.4
- */
- public static String encodeBase64URLSafeString(final byte[] binaryData) {
- return StringUtils.newStringUsAscii(encodeBase64(binaryData, false, true));
- }
- /**
- * 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(final byte[] binaryData) {
- return encodeBase64(binaryData, true);
- }
- /**
- * 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 <code>true</code> this encoder will chunk the base64 output into 76 character blocks
- * @return Base64-encoded data.
- * @throws IllegalArgumentException
- * Thrown when the input array needs an output array bigger than {@link Integer#MAX_VALUE}
- */
- public static byte[] encodeBase64(final byte[] binaryData, final boolean isChunked) {
- return encodeBase64(binaryData, isChunked, false);
- }
- /**
- * 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 <code>true</code> this encoder will chunk the base64 output into 76 character blocks
- * @param urlSafe
- * if <code>true</code> this encoder will emit - and _ instead of the usual + and / characters.
- * <b>Note: no padding is added when encoding using the URL-safe alphabet.</b>
- * @return Base64-encoded data.
- * @throws IllegalArgumentException
- * Thrown when the input array needs an output array bigger than {@link Integer#MAX_VALUE}
- * @since 1.4
- */
- public static byte[] encodeBase64(final byte[] binaryData, final boolean isChunked, final boolean urlSafe) {
- return encodeBase64(binaryData, isChunked, urlSafe, Integer.MAX_VALUE);
- }
- /**
- * 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 <code>true</code> this encoder will chunk the base64 output into 76 character blocks
- * @param urlSafe
- * if <code>true</code> this encoder will emit - and _ instead of the usual + and / characters.
- * <b>Note: no padding is added when encoding using the URL-safe alphabet.</b>
- * @param maxResultSize
- * The maximum result size to accept.
- * @return Base64-encoded data.
- * @throws IllegalArgumentException
- * Thrown when the input array needs an output array bigger than maxResultSize
- * @since 1.4
- */
- public static byte[] encodeBase64(final byte[] binaryData, final boolean isChunked,
- final boolean urlSafe, final int maxResultSize) {
- if (binaryData == null || binaryData.length == 0) {
- return binaryData;
- }
- // Create this so can use the super-class method
- // Also ensures that the same roundings are performed by the ctor and the code
- final Base64 b64 = isChunked ? new Base64(urlSafe) : new Base64(0, CHUNK_SEPARATOR, urlSafe);
- final long len = b64.getEncodedLength(binaryData);
- if (len > maxResultSize) {
- throw new IllegalArgumentException("Input array too big, the output array would be bigger (" +
- len +
- ") than the specified maximum size of " +
- maxResultSize);
- }
- return b64.encode(binaryData);
- }
- /**
- * Decodes a Base64 String into octets.
- * <p>
- * <b>Note:</b> this method seamlessly handles data encoded in URL-safe or normal mode.
- * </p>
- *
- * @param base64String
- * String containing Base64 data
- * @return Array containing decoded data.
- * @since 1.4
- */
- public static byte[] decodeBase64(final String base64String) {
- return new Base64().decode(base64String);
- }
- /**
- * Decodes Base64 data into octets.
- * <p>
- * <b>Note:</b> this method seamlessly handles data encoded in URL-safe or normal mode.
- * </p>
- *
- * @param base64Data
- * Byte array containing Base64 data
- * @return Array containing decoded data.
- */
- public static byte[] decodeBase64(final byte[] base64Data) {
- return new Base64().decode(base64Data);
- }
- // Implementation of the Encoder Interface
- // Implementation of integer encoding used for crypto
- /**
- * Decodes a byte64-encoded integer according to crypto standards such as W3C's XML-Signature.
- *
- * @param pArray
- * a byte array containing base64 character data
- * @return A BigInteger
- * @since 1.4
- */
- public static BigInteger decodeInteger(final byte[] pArray) {
- return new BigInteger(1, decodeBase64(pArray));
- }
- /**
- * Encodes to a byte64-encoded integer according to crypto standards such as W3C's XML-Signature.
- *
- * @param bigInt
- * a BigInteger
- * @return A byte array containing base64 character data
- * @throws NullPointerException
- * if null is passed in
- * @since 1.4
- */
- public static byte[] encodeInteger(final BigInteger bigInt) {
- if (bigInt == null) {
- throw new NullPointerException("encodeInteger called with null parameter");
- }
- return encodeBase64(toIntegerBytes(bigInt), false);
- }
- /**
- * Returns a byte-array representation of a <code>BigInteger</code> without sign bit.
- *
- * @param bigInt
- * <code>BigInteger</code> to be converted
- * @return a byte array representation of the BigInteger parameter
- */
- static byte[] toIntegerBytes(final BigInteger bigInt) {
- int bitlen = bigInt.bitLength();
- // round bitlen
- bitlen = ((bitlen + 7) >> 3) << 3;
- final byte[] bigBytes = bigInt.toByteArray();
- if (((bigInt.bitLength() % 8) != 0) && (((bigInt.bitLength() / 8) + 1) == (bitlen / 8))) {
- return bigBytes;
- }
- // set up params for copying everything but sign bit
- int startSrc = 0;
- int len = bigBytes.length;
- // if bigInt is exactly byte-aligned, just skip signbit in copy
- if ((bigInt.bitLength() % 8) == 0) {
- startSrc = 1;
- len--;
- }
- final int startDst = bitlen / 8 - len; // to pad w/ nulls as per spec
- final byte[] resizedBytes = new byte[bitlen / 8];
- System.arraycopy(bigBytes, startSrc, resizedBytes, startDst, len);
- return resizedBytes;
- }
- /**
- * Returns whether or not the <code>octet</code> is in the Base64 alphabet.
- *
- * @param octet
- * The value to test
- * @return <code>true</code> if the value is defined in the the Base64 alphabet <code>false</code> otherwise.
- */
- @Override
- protected boolean isInAlphabet(final byte octet) {
- return octet >= 0 && octet < decodeTable.length && decodeTable[octet] != -1;
- }
- }