/* | |
* 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; | |
import org.apache.commons.codec.BinaryDecoder; | |
import org.apache.commons.codec.BinaryEncoder; | |
import org.apache.commons.codec.DecoderException; | |
import org.apache.commons.codec.EncoderException; | |
/** | |
* 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> | |
* <p> | |
* The class can be parameterized in the following manner with various constructors: | |
* <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> | |
* <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> | |
* | |
* @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a> | |
* @author Apache Software Foundation | |
* @since 1.0 | |
* @version $Id: Base64.java 801706 2009-08-06 16:27:06Z niallp $ | |
*/ | |
public class Base64Codec implements BinaryEncoder, BinaryDecoder { | |
private static final int DEFAULT_BUFFER_RESIZE_FACTOR = 2; | |
private static final int DEFAULT_BUFFER_SIZE = 8192; | |
/** | |
* 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. | |
* | |
* <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', '-', '_' | |
}; | |
/** | |
* Byte used to pad output. | |
*/ | |
private static final byte PAD = '='; | |
/** | |
* 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 = { | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, 62, -1, 63, 52, 53, 54, | |
55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, | |
5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, | |
24, 25, -1, -1, -1, -1, 63, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, | |
35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 | |
}; | |
/** Mask used to extract 6 bits, used when encoding */ | |
private static final int MASK_6BITS = 0x3f; | |
/** Mask used to extract 8 bits, used in decoding base64 bytes */ | |
private static final int MASK_8BITS = 0xff; | |
// 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; | |
/** | |
* Line length for encoding. Not used when decoding. A value of zero or less implies no chunking of the base64 | |
* encoded data. | |
*/ | |
private final int lineLength; | |
/** | |
* 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; | |
/** | |
* Buffer for streaming. | |
*/ | |
private byte[] buffer; | |
/** | |
* Position where next character should be written in the buffer. | |
*/ | |
private int pos; | |
/** | |
* Position where next character should be read from the buffer. | |
*/ | |
private int readPos; | |
/** | |
* Variable tracks how many characters have been written to the current line. Only used when encoding. We use it to | |
* make sure each encoded line never goes beyond lineLength (if lineLength > 0). | |
*/ | |
private int currentLinePos; | |
/** | |
* Writes to the buffer only occur after every 3 reads when encoding, an every 4 reads when decoding. This variable | |
* helps track that. | |
*/ | |
private int modulus; | |
/** | |
* Boolean flag to indicate the EOF has been reached. Once EOF has been reached, this Base64 object becomes useless, | |
* and must be thrown away. | |
*/ | |
private boolean eof; | |
/** | |
* Place holder for the 3 bytes we're dealing with for our base64 logic. Bitwise operations store and extract the | |
* base64 encoding or decoding from this variable. | |
*/ | |
private int x; | |
/** | |
* Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe 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> | |
*/ | |
public Base64Codec() { | |
this(false); | |
} | |
/** | |
* 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 Base64Codec(boolean urlSafe) { | |
this(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 Base64Codec(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 Base64Codec(int lineLength, 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. | |
* @throws IllegalArgumentException | |
* The provided lineSeparator included some base64 characters. That's not going to work! | |
* @since 1.4 | |
*/ | |
public Base64Codec(int lineLength, byte[] lineSeparator, boolean urlSafe) { | |
if (lineSeparator == null) { | |
lineLength = 0; // disable chunk-separating | |
lineSeparator = CHUNK_SEPARATOR; // this just gets ignored | |
} | |
this.lineLength = lineLength > 0 ? (lineLength / 4) * 4 : 0; | |
this.lineSeparator = new byte[lineSeparator.length]; | |
System.arraycopy(lineSeparator, 0, this.lineSeparator, 0, lineSeparator.length); | |
if (lineLength > 0) { | |
this.encodeSize = 4 + lineSeparator.length; | |
} else { | |
this.encodeSize = 4; | |
} | |
this.decodeSize = this.encodeSize - 1; | |
if (containsBase64Byte(lineSeparator)) { | |
String sep = StringUtils.newStringUtf8(lineSeparator); | |
throw new IllegalArgumentException("lineSeperator must not contain base64 characters: [" + sep + "]"); | |
} | |
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; | |
} | |
/** | |
* Returns true if this Base64 object has buffered data for reading. | |
* | |
* @return true if there is Base64 object still available for reading. | |
*/ | |
boolean hasData() { | |
return this.buffer != null; | |
} | |
/** | |
* Returns the amount of buffered data available for reading. | |
* | |
* @return The amount of buffered data available for reading. | |
*/ | |
int avail() { | |
return buffer != null ? pos - readPos : 0; | |
} | |
/** Doubles our buffer. */ | |
private void resizeBuffer() { | |
if (buffer == null) { | |
buffer = new byte[DEFAULT_BUFFER_SIZE]; | |
pos = 0; | |
readPos = 0; | |
} else { | |
byte[] b = new byte[buffer.length * DEFAULT_BUFFER_RESIZE_FACTOR]; | |
System.arraycopy(buffer, 0, b, 0, buffer.length); | |
buffer = b; | |
} | |
} | |
/** | |
* Extracts buffered data into the provided byte[] array, starting at position bPos, up to a maximum of bAvail | |
* bytes. Returns how many bytes were actually extracted. | |
* | |
* @param b | |
* byte[] array to extract the buffered data into. | |
* @param bPos | |
* position in byte[] array to start extraction at. | |
* @param bAvail | |
* amount of bytes we're allowed to extract. We may extract fewer (if fewer are available). | |
* @return The number of bytes successfully extracted into the provided byte[] array. | |
*/ | |
int readResults(byte[] b, int bPos, int bAvail) { | |
if (buffer != null) { | |
int len = Math.min(avail(), bAvail); | |
if (buffer != b) { | |
System.arraycopy(buffer, readPos, b, bPos, len); | |
readPos += len; | |
if (readPos >= pos) { | |
buffer = null; | |
} | |
} else { | |
// Re-using the original consumer's output array is only | |
// allowed for one round. | |
buffer = null; | |
} | |
return len; | |
} | |
return eof ? -1 : 0; | |
} | |
/** | |
* Sets the streaming buffer. This is a small optimization where we try to buffer directly to the consumer's output | |
* array for one round (if the consumer calls this method first) instead of starting our own buffer. | |
* | |
* @param out | |
* byte[] array to buffer directly to. | |
* @param outPos | |
* Position to start buffering into. | |
* @param outAvail | |
* Amount of bytes available for direct buffering. | |
*/ | |
void setInitialBuffer(byte[] out, int outPos, int outAvail) { | |
// We can re-use consumer's original output array under | |
// special circumstances, saving on some System.arraycopy(). | |
if (out != null && out.length == outAvail) { | |
buffer = out; | |
pos = outPos; | |
readPos = outPos; | |
} | |
} | |
/** | |
* <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, so flush last | |
* remaining bytes (if not multiple of 3). | |
* </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. | |
*/ | |
void encode(byte[] in, int inPos, int inAvail) { | |
if (eof) { | |
return; | |
} | |
// inAvail < 0 is how we're informed of EOF in the underlying data we're | |
// encoding. | |
if (inAvail < 0) { | |
eof = true; | |
if (buffer == null || buffer.length - pos < encodeSize) { | |
resizeBuffer(); | |
} | |
switch (modulus) { | |
case 1 : | |
buffer[pos++] = encodeTable[(x >> 2) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[(x << 4) & MASK_6BITS]; | |
// URL-SAFE skips the padding to further reduce size. | |
if (encodeTable == STANDARD_ENCODE_TABLE) { | |
buffer[pos++] = PAD; | |
buffer[pos++] = PAD; | |
} | |
break; | |
case 2 : | |
buffer[pos++] = encodeTable[(x >> 10) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[(x >> 4) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[(x << 2) & MASK_6BITS]; | |
// URL-SAFE skips the padding to further reduce size. | |
if (encodeTable == STANDARD_ENCODE_TABLE) { | |
buffer[pos++] = PAD; | |
} | |
break; | |
} | |
if (lineLength > 0 && pos > 0) { | |
System.arraycopy(lineSeparator, 0, buffer, pos, lineSeparator.length); | |
pos += lineSeparator.length; | |
} | |
} else { | |
for (int i = 0; i < inAvail; i++) { | |
if (buffer == null || buffer.length - pos < encodeSize) { | |
resizeBuffer(); | |
} | |
modulus = (++modulus) % 3; | |
int b = in[inPos++]; | |
if (b < 0) { | |
b += 256; | |
} | |
x = (x << 8) + b; | |
if (0 == modulus) { | |
buffer[pos++] = encodeTable[(x >> 18) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[(x >> 12) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[(x >> 6) & MASK_6BITS]; | |
buffer[pos++] = encodeTable[x & MASK_6BITS]; | |
currentLinePos += 4; | |
if (lineLength > 0 && lineLength <= currentLinePos) { | |
System.arraycopy(lineSeparator, 0, buffer, pos, lineSeparator.length); | |
pos += lineSeparator.length; | |
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. | |
*/ | |
void decode(byte[] in, int inPos, int inAvail) { | |
if (eof) { | |
return; | |
} | |
if (inAvail < 0) { | |
eof = true; | |
} | |
for (int i = 0; i < inAvail; i++) { | |
if (buffer == null || buffer.length - pos < decodeSize) { | |
resizeBuffer(); | |
} | |
byte b = in[inPos++]; | |
if (b == PAD) { | |
// We're done. | |
eof = true; | |
break; | |
} else { | |
if (b >= 0 && b < DECODE_TABLE.length) { | |
int result = DECODE_TABLE[b]; | |
if (result >= 0) { | |
modulus = (++modulus) % 4; | |
x = (x << 6) + result; | |
if (modulus == 0) { | |
buffer[pos++] = (byte) ((x >> 16) & MASK_8BITS); | |
buffer[pos++] = (byte) ((x >> 8) & MASK_8BITS); | |
buffer[pos++] = (byte) (x & 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 (eof && modulus != 0) { | |
x = x << 6; | |
switch (modulus) { | |
case 2 : | |
x = x << 6; | |
buffer[pos++] = (byte) ((x >> 16) & MASK_8BITS); | |
break; | |
case 3 : | |
buffer[pos++] = (byte) ((x >> 16) & MASK_8BITS); | |
buffer[pos++] = (byte) ((x >> 8) & MASK_8BITS); | |
break; | |
} | |
} | |
} | |
/** | |
* 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(byte octet) { | |
return octet == PAD || (octet >= 0 && octet < DECODE_TABLE.length && DECODE_TABLE[octet] != -1); | |
} | |
/** | |
* 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; | |
* false, otherwise | |
*/ | |
public static boolean isArrayByteBase64(byte[] arrayOctet) { | |
for (int i = 0; i < arrayOctet.length; i++) { | |
if (!isBase64(arrayOctet[i]) && !isWhiteSpace(arrayOctet[i])) { | |
return false; | |
} | |
} | |
return true; | |
} | |
/** | |
* Tests a given byte array to see if it contains only valid characters within the Base64 alphabet. | |
* | |
* @param arrayOctet | |
* byte array to test | |
* @return <code>true</code> if any byte is a valid character in the Base64 alphabet; false herwise | |
*/ | |
private static boolean containsBase64Byte(byte[] arrayOctet) { | |
for (int i = 0; i < arrayOctet.length; i++) { | |
if (isBase64(arrayOctet[i])) { | |
return true; | |
} | |
} | |
return false; | |
} | |
/** | |
* 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(byte[] binaryData) { | |
return encodeBase64(binaryData, false); | |
} | |
/** | |
* Encodes binary data using the base64 algorithm into 76 character blocks separated by CRLF. | |
* | |
* @param binaryData | |
* binary data to encode | |
* @return String containing Base64 characters. | |
* @since 1.4 | |
*/ | |
public static String encodeBase64String(byte[] binaryData) { | |
return StringUtils.newStringUtf8(encodeBase64(binaryData, 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. | |
* | |
* @param binaryData | |
* binary data to encode | |
* @return byte[] containing Base64 characters in their UTF-8 representation. | |
* @since 1.4 | |
*/ | |
public static byte[] encodeBase64URLSafe(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. | |
* | |
* @param binaryData | |
* binary data to encode | |
* @return String containing Base64 characters | |
* @since 1.4 | |
*/ | |
public static String encodeBase64URLSafeString(byte[] binaryData) { | |
return StringUtils.newStringUtf8(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(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[] or String. | |
* | |
* @param pObject | |
* Object to decode | |
* @return An object (of type byte[]) containing the binary data which corresponds to the byte[] or String supplied. | |
* @throws DecoderException | |
* if the parameter supplied is not of type byte[] | |
*/ | |
public Object decode(Object pObject) throws DecoderException { | |
if (pObject instanceof byte[]) { | |
return decode((byte[]) pObject); | |
} else if (pObject instanceof String) { | |
return decode((String) pObject); | |
} else { | |
throw new DecoderException("Parameter supplied to Base64 decode is not a byte[] or a String"); | |
} | |
} | |
/** | |
* Decodes a String containing containing characters in the Base64 alphabet. | |
* | |
* @param pArray | |
* A String containing Base64 character data | |
* @return a byte array containing binary data | |
* @since 1.4 | |
*/ | |
public byte[] decode(String pArray) { | |
return decode(StringUtils.getBytesUtf8(pArray)); | |
} | |
/** | |
* 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) { | |
reset(); | |
if (pArray == null || pArray.length == 0) { | |
return pArray; | |
} | |
long len = (pArray.length * 3) / 4; | |
byte[] buf = new byte[(int) len]; | |
setInitialBuffer(buf, 0, buf.length); | |
decode(pArray, 0, pArray.length); | |
decode(pArray, 0, -1); // Notify decoder of EOF. | |
// Would be nice to just return buf (like we sometimes do in the encode | |
// logic), but we have no idea what the line-length was (could even be | |
// variable). So we cannot determine ahead of time exactly how big an | |
// array is necessary. Hence the need to construct a 2nd byte array to | |
// hold the final result: | |
byte[] result = new byte[pos]; | |
readResults(result, 0, result.length); | |
return result; | |
} | |
/** | |
* 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(byte[] binaryData, 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. | |
* @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(byte[] binaryData, boolean isChunked, 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. | |
* @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(byte[] binaryData, boolean isChunked, boolean urlSafe, int maxResultSize) { | |
if (binaryData == null || binaryData.length == 0) { | |
return binaryData; | |
} | |
long len = getEncodeLength(binaryData, CHUNK_SIZE, CHUNK_SEPARATOR); | |
if (len > maxResultSize) { | |
throw new IllegalArgumentException("Input array too big, the output array would be bigger (" + | |
len + | |
") than the specified maxium size of " + | |
maxResultSize); | |
} | |
Base64Codec b64 = isChunked ? new Base64Codec(urlSafe) : new Base64Codec(0, CHUNK_SEPARATOR, urlSafe); | |
return b64.encode(binaryData); | |
} | |
/** | |
* Decodes a Base64 String into octets | |
* | |
* @param base64String | |
* String containing Base64 data | |
* @return Array containing decoded data. | |
* @since 1.4 | |
*/ | |
public static byte[] decodeBase64(String base64String) { | |
return new Base64Codec().decode(base64String); | |
} | |
/** | |
* Decodes Base64 data into octets | |
* | |
* @param base64Data | |
* Byte array containing Base64 data | |
* @return Array containing decoded data. | |
*/ | |
public static byte[] decodeBase64(byte[] base64Data) { | |
return new Base64Codec().decode(base64Data); | |
} | |
/** | |
* 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). | |
* @deprecated This method is no longer needed | |
*/ | |
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 ' ' : | |
case '\n' : | |
case '\r' : | |
case '\t' : | |
break; | |
default : | |
groomedData[bytesCopied++] = data[i]; | |
} | |
} | |
byte packedData[] = new byte[bytesCopied]; | |
System.arraycopy(groomedData, 0, packedData, 0, bytesCopied); | |
return packedData; | |
} | |
/** | |
* Checks if a byte value is whitespace or not. | |
* | |
* @param byteToCheck | |
* the byte to check | |
* @return true if byte is whitespace, false otherwise | |
*/ | |
private static boolean isWhiteSpace(byte byteToCheck) { | |
switch (byteToCheck) { | |
case ' ' : | |
case '\n' : | |
case '\r' : | |
case '\t' : | |
return true; | |
default : | |
return false; | |
} | |
} | |
// 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 EncoderException | |
* if the parameter supplied is not of type byte[] | |
*/ | |
public Object encode(Object pObject) throws EncoderException { | |
if (!(pObject instanceof byte[])) { | |
throw new EncoderException("Parameter supplied to Base64 encode is not a byte[]"); | |
} | |
return encode((byte[]) pObject); | |
} | |
/** | |
* Encodes a byte[] containing binary data, into a String containing characters in the Base64 alphabet. | |
* | |
* @param pArray | |
* a byte array containing binary data | |
* @return A String containing only Base64 character data | |
* @since 1.4 | |
*/ | |
public String encodeToString(byte[] pArray) { | |
return StringUtils.newStringUtf8(encode(pArray)); | |
} | |
/** | |
* 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) { | |
reset(); | |
if (pArray == null || pArray.length == 0) { | |
return pArray; | |
} | |
long len = getEncodeLength(pArray, lineLength, lineSeparator); | |
byte[] buf = new byte[(int) len]; | |
setInitialBuffer(buf, 0, buf.length); | |
encode(pArray, 0, pArray.length); | |
encode(pArray, 0, -1); // Notify encoder of EOF. | |
// Encoder might have resized, even though it was unnecessary. | |
if (buffer != buf) { | |
readResults(buf, 0, buf.length); | |
} | |
// In URL-SAFE mode we skip the padding characters, so sometimes our | |
// final length is a bit smaller. | |
if (isUrlSafe() && pos < buf.length) { | |
byte[] smallerBuf = new byte[pos]; | |
System.arraycopy(buf, 0, smallerBuf, 0, pos); | |
buf = smallerBuf; | |
} | |
return buf; | |
} | |
/** | |
* Pre-calculates the amount of space needed to base64-encode the supplied array. | |
* | |
* @param pArray byte[] array which will later be encoded | |
* @param chunkSize line-length of the output (<= 0 means no chunking) between each | |
* chunkSeparator (e.g. CRLF). | |
* @param chunkSeparator the sequence of bytes used to separate chunks of output (e.g. CRLF). | |
* | |
* @return amount of space needed to encoded the supplied array. Returns | |
* a long since a max-len array will require Integer.MAX_VALUE + 33%. | |
*/ | |
private static long getEncodeLength(byte[] pArray, int chunkSize, byte[] chunkSeparator) { | |
// base64 always encodes to multiples of 4. | |
chunkSize = (chunkSize / 4) * 4; | |
long len = (pArray.length * 4) / 3; | |
long mod = len % 4; | |
if (mod != 0) { | |
len += 4 - mod; | |
} | |
if (chunkSize > 0) { | |
boolean lenChunksPerfectly = len % chunkSize == 0; | |
len += (len / chunkSize) * chunkSeparator.length; | |
if (!lenChunksPerfectly) { | |
len += chunkSeparator.length; | |
} | |
} | |
return len; | |
} | |
// 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(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(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(BigInteger bigInt) { | |
int bitlen = bigInt.bitLength(); | |
// round bitlen | |
bitlen = ((bitlen + 7) >> 3) << 3; | |
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--; | |
} | |
int startDst = bitlen / 8 - len; // to pad w/ nulls as per spec | |
byte[] resizedBytes = new byte[bitlen / 8]; | |
System.arraycopy(bigBytes, startSrc, resizedBytes, startDst, len); | |
return resizedBytes; | |
} | |
/** | |
* Resets this Base64 object to its initial newly constructed state. | |
*/ | |
private void reset() { | |
buffer = null; | |
pos = 0; | |
readPos = 0; | |
currentLinePos = 0; | |
modulus = 0; | |
eof = false; | |
} | |
} |