300 lines
13 KiB
Java
300 lines
13 KiB
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.tomcat.util.buf;
|
|
|
|
import java.nio.ByteBuffer;
|
|
import java.nio.CharBuffer;
|
|
import java.nio.charset.CharsetDecoder;
|
|
import java.nio.charset.CoderResult;
|
|
import java.nio.charset.StandardCharsets;
|
|
|
|
/**
|
|
* Decodes bytes to UTF-8. Extracted from Apache Harmony and modified to reject
|
|
* code points from U+D800 to U+DFFF as per RFC3629. The standard Java decoder
|
|
* does not reject these. It has also been modified to reject code points
|
|
* greater than U+10FFFF which the standard Java decoder rejects but the harmony
|
|
* one does not.
|
|
*/
|
|
public class Utf8Decoder extends CharsetDecoder {
|
|
|
|
// The next table contains information about UTF-8 charset and
|
|
// correspondence of 1st byte to the length of sequence
|
|
// For information please visit http://www.ietf.org/rfc/rfc3629.txt
|
|
//
|
|
// Please note, o means 0, actually.
|
|
// -------------------------------------------------------------------
|
|
// 0 1 2 3 Value
|
|
// -------------------------------------------------------------------
|
|
// oxxxxxxx 00000000 00000000 0xxxxxxx
|
|
// 11oyyyyy 1oxxxxxx 00000000 00000yyy yyxxxxxx
|
|
// 111ozzzz 1oyyyyyy 1oxxxxxx 00000000 zzzzyyyy yyxxxxxx
|
|
// 1111ouuu 1ouuzzzz 1oyyyyyy 1oxxxxxx 000uuuuu zzzzyyyy yyxxxxxx
|
|
private static final int remainingBytes[] = {
|
|
// 1owwwwww
|
|
-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, -1, -1, -1, -1, -1,
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
// 11oyyyyy
|
|
-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,
|
|
// 111ozzzz
|
|
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
|
|
// 1111ouuu
|
|
3, 3, 3, 3, 3, -1, -1, -1,
|
|
// > 11110111
|
|
-1, -1, -1, -1, -1, -1, -1, -1};
|
|
private static final int remainingNumbers[] = {0, // 0 1 2 3
|
|
4224, // (01o00000b << 6)+(1o000000b)
|
|
401536, // (011o0000b << 12)+(1o000000b << 6)+(1o000000b)
|
|
29892736 // (0111o000b << 18)+(1o000000b << 12)+(1o000000b <<
|
|
// 6)+(1o000000b)
|
|
};
|
|
private static final int lowerEncodingLimit[] = {-1, 0x80, 0x800, 0x10000};
|
|
|
|
|
|
public Utf8Decoder() {
|
|
super(StandardCharsets.UTF_8, 1.0f, 1.0f);
|
|
}
|
|
|
|
|
|
@Override
|
|
protected CoderResult decodeLoop(ByteBuffer in, CharBuffer out) {
|
|
if (in.hasArray() && out.hasArray()) {
|
|
return decodeHasArray(in, out);
|
|
}
|
|
return decodeNotHasArray(in, out);
|
|
}
|
|
|
|
|
|
private CoderResult decodeNotHasArray(ByteBuffer in, CharBuffer out) {
|
|
int outRemaining = out.remaining();
|
|
int pos = in.position();
|
|
int limit = in.limit();
|
|
try {
|
|
while (pos < limit) {
|
|
if (outRemaining == 0) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
int jchar = in.get();
|
|
if (jchar < 0) {
|
|
jchar = jchar & 0x7F;
|
|
int tail = remainingBytes[jchar];
|
|
if (tail == -1) {
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
if (limit - pos < 1 + tail) {
|
|
// No early test for invalid sequences here as peeking
|
|
// at the next byte is harder
|
|
return CoderResult.UNDERFLOW;
|
|
}
|
|
int nextByte;
|
|
for (int i = 0; i < tail; i++) {
|
|
nextByte = in.get() & 0xFF;
|
|
if ((nextByte & 0xC0) != 0x80) {
|
|
return CoderResult.malformedForLength(1 + i);
|
|
}
|
|
jchar = (jchar << 6) + nextByte;
|
|
}
|
|
jchar -= remainingNumbers[tail];
|
|
if (jchar < lowerEncodingLimit[tail]) {
|
|
// Should have been encoded in a fewer octets
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
pos += tail;
|
|
}
|
|
// Apache Tomcat added test
|
|
if (jchar >= 0xD800 && jchar <= 0xDFFF) {
|
|
return CoderResult.unmappableForLength(3);
|
|
}
|
|
// Apache Tomcat added test
|
|
if (jchar > 0x10FFFF) {
|
|
return CoderResult.unmappableForLength(4);
|
|
}
|
|
if (jchar <= 0xffff) {
|
|
out.put((char) jchar);
|
|
outRemaining--;
|
|
} else {
|
|
if (outRemaining < 2) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
out.put((char) ((jchar >> 0xA) + 0xD7C0));
|
|
out.put((char) ((jchar & 0x3FF) + 0xDC00));
|
|
outRemaining -= 2;
|
|
}
|
|
pos++;
|
|
}
|
|
return CoderResult.UNDERFLOW;
|
|
} finally {
|
|
in.position(pos);
|
|
}
|
|
}
|
|
|
|
|
|
private CoderResult decodeHasArray(ByteBuffer in, CharBuffer out) {
|
|
int outRemaining = out.remaining();
|
|
int pos = in.position();
|
|
int limit = in.limit();
|
|
final byte[] bArr = in.array();
|
|
final char[] cArr = out.array();
|
|
final int inIndexLimit = limit + in.arrayOffset();
|
|
int inIndex = pos + in.arrayOffset();
|
|
int outIndex = out.position() + out.arrayOffset();
|
|
// if someone would change the limit in process,
|
|
// he would face consequences
|
|
for (; inIndex < inIndexLimit && outRemaining > 0; inIndex++) {
|
|
int jchar = bArr[inIndex];
|
|
if (jchar < 0) {
|
|
jchar = jchar & 0x7F;
|
|
// If first byte is invalid, tail will be set to -1
|
|
int tail = remainingBytes[jchar];
|
|
if (tail == -1) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// Additional checks to detect invalid sequences ASAP
|
|
// Checks derived from Unicode 6.2, Chapter 3, Table 3-7
|
|
// Check 2nd byte
|
|
int tailAvailable = inIndexLimit - inIndex - 1;
|
|
if (tailAvailable > 0) {
|
|
// First byte C2..DF, second byte 80..BF
|
|
if (jchar > 0x41 && jchar < 0x60 &&
|
|
(bArr[inIndex + 1] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte E0, second byte A0..BF
|
|
if (jchar == 0x60 && (bArr[inIndex + 1] & 0xE0) != 0xA0) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte E1..EC, second byte 80..BF
|
|
if (jchar > 0x60 && jchar < 0x6D &&
|
|
(bArr[inIndex + 1] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte ED, second byte 80..9F
|
|
if (jchar == 0x6D && (bArr[inIndex + 1] & 0xE0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte EE..EF, second byte 80..BF
|
|
if (jchar > 0x6D && jchar < 0x70 &&
|
|
(bArr[inIndex + 1] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte F0, second byte 90..BF
|
|
if (jchar == 0x70 &&
|
|
((bArr[inIndex + 1] & 0xFF) < 0x90 ||
|
|
(bArr[inIndex + 1] & 0xFF) > 0xBF)) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte F1..F3, second byte 80..BF
|
|
if (jchar > 0x70 && jchar < 0x74 &&
|
|
(bArr[inIndex + 1] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
// First byte F4, second byte 80..8F
|
|
if (jchar == 0x74 &&
|
|
(bArr[inIndex + 1] & 0xF0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
}
|
|
// Check third byte if present and expected
|
|
if (tailAvailable > 1 && tail > 1) {
|
|
if ((bArr[inIndex + 2] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(2);
|
|
}
|
|
}
|
|
// Check fourth byte if present and expected
|
|
if (tailAvailable > 2 && tail > 2) {
|
|
if ((bArr[inIndex + 3] & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(3);
|
|
}
|
|
}
|
|
if (tailAvailable < tail) {
|
|
break;
|
|
}
|
|
for (int i = 0; i < tail; i++) {
|
|
int nextByte = bArr[inIndex + i + 1] & 0xFF;
|
|
if ((nextByte & 0xC0) != 0x80) {
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1 + i);
|
|
}
|
|
jchar = (jchar << 6) + nextByte;
|
|
}
|
|
jchar -= remainingNumbers[tail];
|
|
if (jchar < lowerEncodingLimit[tail]) {
|
|
// Should have been encoded in fewer octets
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
inIndex += tail;
|
|
}
|
|
// Apache Tomcat added test
|
|
if (jchar >= 0xD800 && jchar <= 0xDFFF) {
|
|
return CoderResult.unmappableForLength(3);
|
|
}
|
|
// Apache Tomcat added test
|
|
if (jchar > 0x10FFFF) {
|
|
return CoderResult.unmappableForLength(4);
|
|
}
|
|
if (jchar <= 0xffff) {
|
|
cArr[outIndex++] = (char) jchar;
|
|
outRemaining--;
|
|
} else {
|
|
if (outRemaining < 2) {
|
|
// Encoded with 4 bytes. inIndex currently points
|
|
// to the final byte. Move it back to first byte.
|
|
inIndex -= 3;
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
cArr[outIndex++] = (char) ((jchar >> 0xA) + 0xD7C0);
|
|
cArr[outIndex++] = (char) ((jchar & 0x3FF) + 0xDC00);
|
|
outRemaining -= 2;
|
|
}
|
|
}
|
|
in.position(inIndex - in.arrayOffset());
|
|
out.position(outIndex - out.arrayOffset());
|
|
return (outRemaining == 0 && inIndex < inIndexLimit) ?
|
|
CoderResult.OVERFLOW :
|
|
CoderResult.UNDERFLOW;
|
|
}
|
|
}
|