| /* |
| * 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.compress.archivers.tar; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.UncheckedIOException; |
| import java.math.BigInteger; |
| import java.nio.ByteBuffer; |
| import java.nio.charset.Charset; |
| import java.nio.charset.StandardCharsets; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| import org.apache.commons.compress.archivers.zip.ZipEncoding; |
| import org.apache.commons.compress.archivers.zip.ZipEncodingHelper; |
| import org.apache.commons.compress.utils.CharsetNames; |
| import org.apache.commons.compress.utils.IOUtils; |
| import org.apache.commons.compress.utils.ParsingUtils; |
| |
| /** |
| * This class provides static utility methods to work with byte streams. |
| * |
| * @Immutable |
| */ |
| // CheckStyle:HideUtilityClassConstructorCheck OFF (bc) |
| public class TarUtils { |
| |
| private static final int BYTE_MASK = 255; |
| |
| static final ZipEncoding DEFAULT_ENCODING = ZipEncodingHelper.getZipEncoding(Charset.defaultCharset()); |
| |
| /** |
| * Encapsulates the algorithms used up to Commons Compress 1.3 as ZipEncoding. |
| */ |
| static final ZipEncoding FALLBACK_ENCODING = new ZipEncoding() { |
| |
| @Override |
| public boolean canEncode(final String name) { |
| return true; |
| } |
| |
| @Override |
| public String decode(final byte[] buffer) { |
| final int length = buffer.length; |
| final StringBuilder result = new StringBuilder(length); |
| for (final byte b : buffer) { |
| if (b == 0) { // Trailing null |
| break; |
| } |
| result.append((char) (b & 0xFF)); // Allow for sign-extension |
| } |
| return result.toString(); |
| } |
| |
| @Override |
| public ByteBuffer encode(final String name) { |
| final int length = name.length(); |
| final byte[] buf = new byte[length]; |
| // copy until end of input or output is reached. |
| for (int i = 0; i < length; ++i) { |
| buf[i] = (byte) name.charAt(i); |
| } |
| return ByteBuffer.wrap(buf); |
| } |
| }; |
| |
| /** |
| * Computes the checksum of a tar entry header. |
| * |
| * @param buf The tar entry's header buffer. |
| * @return The computed checksum. |
| */ |
| public static long computeCheckSum(final byte[] buf) { |
| long sum = 0; |
| for (final byte element : buf) { |
| sum += BYTE_MASK & element; |
| } |
| return sum; |
| } |
| |
| // Helper method to generate the exception message |
| private static String exceptionMessage(final byte[] buffer, final int offset, final int length, final int current, final byte currentByte) { |
| // default charset is good enough for an exception message, |
| // |
| // the alternative was to modify parseOctal and |
| // parseOctalOrBinary to receive the ZipEncoding of the |
| // archive (deprecating the existing public methods, of |
| // course) and dealing with the fact that ZipEncoding#decode |
| // can throw an IOException which parseOctal* doesn't declare |
| String string = new String(buffer, offset, length, Charset.defaultCharset()); |
| |
| string = string.replace("\0", "{NUL}"); // Replace NULs to allow string to be printed |
| return "Invalid byte " + currentByte + " at offset " + (current - offset) + " in '" + string + "' len=" + length; |
| } |
| |
| private static void formatBigIntegerBinary(final long value, final byte[] buf, final int offset, final int length, final boolean negative) { |
| final BigInteger val = BigInteger.valueOf(value); |
| final byte[] b = val.toByteArray(); |
| final int len = b.length; |
| if (len > length - 1) { |
| throw new IllegalArgumentException("Value " + value + " is too large for " + length + " byte field."); |
| } |
| final int off = offset + length - len; |
| System.arraycopy(b, 0, buf, off, len); |
| final byte fill = (byte) (negative ? 0xff : 0); |
| for (int i = offset + 1; i < off; i++) { |
| buf[i] = fill; |
| } |
| } |
| |
| /** |
| * Writes an octal value into a buffer. |
| * |
| * Uses {@link #formatUnsignedOctalString} to format the value as an octal string with leading zeros. The converted number is followed by NUL and then |
| * space. |
| * |
| * @param value The value to convert |
| * @param buf The destination buffer |
| * @param offset The starting offset into the buffer. |
| * @param length The size of the buffer. |
| * @return The updated value of offset, i.e. offset+length |
| * @throws IllegalArgumentException if the value (and trailer) will not fit in the buffer |
| */ |
| public static int formatCheckSumOctalBytes(final long value, final byte[] buf, final int offset, final int length) { |
| int idx = length - 2; // for NUL and space |
| formatUnsignedOctalString(value, buf, offset, idx); |
| buf[offset + idx++] = 0; // Trailing null |
| buf[offset + idx] = (byte) ' '; // Trailing space |
| return offset + length; |
| } |
| |
| private static void formatLongBinary(final long value, final byte[] buf, final int offset, final int length, final boolean negative) { |
| final int bits = (length - 1) * 8; |
| final long max = 1L << bits; |
| long val = Math.abs(value); // Long.MIN_VALUE stays Long.MIN_VALUE |
| if (val < 0 || val >= max) { |
| throw new IllegalArgumentException("Value " + value + " is too large for " + length + " byte field."); |
| } |
| if (negative) { |
| val ^= max - 1; |
| val++; |
| val |= 0xffL << bits; |
| } |
| for (int i = offset + length - 1; i >= offset; i--) { |
| buf[i] = (byte) val; |
| val >>= 8; |
| } |
| } |
| |
| /** |
| * Writes an octal long integer into a buffer. |
| * |
| * Uses {@link #formatUnsignedOctalString} to format the value as an octal string with leading zeros. The converted number is followed by a space. |
| * |
| * @param value The value to write as octal |
| * @param buf The destinationbuffer. |
| * @param offset The starting offset into the buffer. |
| * @param length The length of the buffer |
| * @return The updated offset |
| * @throws IllegalArgumentException if the value (and trailer) will not fit in the buffer |
| */ |
| public static int formatLongOctalBytes(final long value, final byte[] buf, final int offset, final int length) { |
| final int idx = length - 1; // For space |
| formatUnsignedOctalString(value, buf, offset, idx); |
| buf[offset + idx] = (byte) ' '; // Trailing space |
| return offset + length; |
| } |
| |
| /** |
| * Writes a long integer into a buffer as an octal string if this will fit, or as a binary number otherwise. |
| * |
| * Uses {@link #formatUnsignedOctalString} to format the value as an octal string with leading zeros. The converted number is followed by a space. |
| * |
| * @param value The value to write into the buffer. |
| * @param buf The destination buffer. |
| * @param offset The starting offset into the buffer. |
| * @param length The length of the buffer. |
| * @return The updated offset. |
| * @throws IllegalArgumentException if the value (and trailer) will not fit in the buffer. |
| * @since 1.4 |
| */ |
| public static int formatLongOctalOrBinaryBytes(final long value, final byte[] buf, final int offset, final int length) { |
| // Check whether we are dealing with UID/GID or SIZE field |
| final long maxAsOctalChar = length == TarConstants.UIDLEN ? TarConstants.MAXID : TarConstants.MAXSIZE; |
| final boolean negative = value < 0; |
| if (!negative && value <= maxAsOctalChar) { // OK to store as octal chars |
| return formatLongOctalBytes(value, buf, offset, length); |
| } |
| if (length < 9) { |
| formatLongBinary(value, buf, offset, length, negative); |
| } else { |
| formatBigIntegerBinary(value, buf, offset, length, negative); |
| } |
| buf[offset] = (byte) (negative ? 0xff : 0x80); |
| return offset + length; |
| } |
| |
| /** |
| * Copies a name into a buffer. Copies characters from the name into the buffer starting at the specified offset. If the buffer is longer than the name, the |
| * buffer is filled with trailing NULs. If the name is longer than the buffer, the output is truncated. |
| * |
| * @param name The header name from which to copy the characters. |
| * @param buf The buffer where the name is to be stored. |
| * @param offset The starting offset into the buffer |
| * @param length The maximum number of header bytes to copy. |
| * @return The updated offset, i.e. offset + length |
| */ |
| public static int formatNameBytes(final String name, final byte[] buf, final int offset, final int length) { |
| try { |
| return formatNameBytes(name, buf, offset, length, DEFAULT_ENCODING); |
| } catch (final IOException ex) { // NOSONAR |
| try { |
| return formatNameBytes(name, buf, offset, length, FALLBACK_ENCODING); |
| } catch (final IOException ex2) { |
| // impossible |
| throw new UncheckedIOException(ex2); // NOSONAR |
| } |
| } |
| } |
| |
| /** |
| * Copies a name into a buffer. Copies characters from the name into the buffer starting at the specified offset. If the buffer is longer than the name, the |
| * buffer is filled with trailing NULs. If the name is longer than the buffer, the output is truncated. |
| * |
| * @param name The header name from which to copy the characters. |
| * @param buf The buffer where the name is to be stored. |
| * @param offset The starting offset into the buffer |
| * @param length The maximum number of header bytes to copy. |
| * @param encoding name of the encoding to use for file names |
| * @since 1.4 |
| * @return The updated offset, i.e. offset + length |
| * @throws IOException on error |
| */ |
| public static int formatNameBytes(final String name, final byte[] buf, final int offset, final int length, final ZipEncoding encoding) throws IOException { |
| int len = name.length(); |
| ByteBuffer b = encoding.encode(name); |
| while (b.limit() > length && len > 0) { |
| b = encoding.encode(name.substring(0, --len)); |
| } |
| final int limit = b.limit() - b.position(); |
| System.arraycopy(b.array(), b.arrayOffset(), buf, offset, limit); |
| // Pad any remaining output bytes with NUL |
| for (int i = limit; i < length; ++i) { |
| buf[offset + i] = 0; |
| } |
| return offset + length; |
| } |
| |
| /** |
| * Writes an octal integer into a buffer. |
| * |
| * Uses {@link #formatUnsignedOctalString} to format the value as an octal string with leading zeros. The converted number is followed by space and NUL |
| * |
| * @param value The value to write |
| * @param buf The buffer to receive the output |
| * @param offset The starting offset into the buffer |
| * @param length The size of the output buffer |
| * @return The updated offset, i.e. offset+length |
| * @throws IllegalArgumentException if the value (and trailer) will not fit in the buffer |
| */ |
| public static int formatOctalBytes(final long value, final byte[] buf, final int offset, final int length) { |
| int idx = length - 2; // For space and trailing null |
| formatUnsignedOctalString(value, buf, offset, idx); |
| buf[offset + idx++] = (byte) ' '; // Trailing space |
| buf[offset + idx] = 0; // Trailing null |
| return offset + length; |
| } |
| |
| /** |
| * Fills a buffer with unsigned octal number, padded with leading zeroes. |
| * |
| * @param value number to convert to octal - treated as unsigned |
| * @param buffer destination buffer |
| * @param offset starting offset in buffer |
| * @param length length of buffer to fill |
| * @throws IllegalArgumentException if the value will not fit in the buffer |
| */ |
| public static void formatUnsignedOctalString(final long value, final byte[] buffer, final int offset, final int length) { |
| int remaining = length; |
| remaining--; |
| if (value == 0) { |
| buffer[offset + remaining--] = (byte) '0'; |
| } else { |
| long val = value; |
| for (; remaining >= 0 && val != 0; --remaining) { |
| // CheckStyle:MagicNumber OFF |
| buffer[offset + remaining] = (byte) ((byte) '0' + (byte) (val & 7)); |
| val = val >>> 3; |
| // CheckStyle:MagicNumber ON |
| } |
| if (val != 0) { |
| throw new IllegalArgumentException(value + "=" + Long.toOctalString(value) + " will not fit in octal number buffer of length " + length); |
| } |
| } |
| |
| for (; remaining >= 0; --remaining) { // leading zeros |
| buffer[offset + remaining] = (byte) '0'; |
| } |
| } |
| |
| private static long parseBinaryBigInteger(final byte[] buffer, final int offset, final int length, final boolean negative) { |
| final byte[] remainder = new byte[length - 1]; |
| System.arraycopy(buffer, offset + 1, remainder, 0, length - 1); |
| BigInteger val = new BigInteger(remainder); |
| if (negative) { |
| // 2's complement |
| val = val.add(BigInteger.valueOf(-1)).not(); |
| } |
| if (val.bitLength() > 63) { |
| throw new IllegalArgumentException("At offset " + offset + ", " + length + " byte binary number exceeds maximum signed long value"); |
| } |
| return negative ? -val.longValue() : val.longValue(); |
| } |
| |
| private static long parseBinaryLong(final byte[] buffer, final int offset, final int length, final boolean negative) { |
| if (length >= 9) { |
| throw new IllegalArgumentException("At offset " + offset + ", " + length + " byte binary number exceeds maximum signed long value"); |
| } |
| long val = 0; |
| for (int i = 1; i < length; i++) { |
| val = (val << 8) + (buffer[offset + i] & 0xff); |
| } |
| if (negative) { |
| // 2's complement |
| val--; |
| val ^= (long) Math.pow(2.0, (length - 1) * 8.0) - 1; |
| } |
| return negative ? -val : val; |
| } |
| |
| /** |
| * Parses a boolean byte from a buffer. Leading spaces and NUL are ignored. The buffer may contain trailing spaces or NULs. |
| * |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @return The boolean value of the bytes. |
| * @throws IllegalArgumentException if an invalid byte is detected. |
| */ |
| public static boolean parseBoolean(final byte[] buffer, final int offset) { |
| return buffer[offset] == 1; |
| } |
| |
| /** |
| * For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map GNU.sparse.map Map of non-null data chunks. It is a string |
| * consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * |
| * @param sparseMap the sparse map string consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * @return unmodifiable list of sparse headers parsed from sparse map |
| * @throws IOException Corrupted TAR archive. |
| * @since 1.21 |
| */ |
| protected static List<TarArchiveStructSparse> parseFromPAX01SparseHeaders(final String sparseMap) throws IOException { |
| final List<TarArchiveStructSparse> sparseHeaders = new ArrayList<>(); |
| final String[] sparseHeaderStrings = sparseMap.split(","); |
| if (sparseHeaderStrings.length % 2 == 1) { |
| throw new IOException("Corrupted TAR archive. Bad format in GNU.sparse.map PAX Header"); |
| } |
| for (int i = 0; i < sparseHeaderStrings.length; i += 2) { |
| final long sparseOffset = ParsingUtils.parseLongValue(sparseHeaderStrings[i]); |
| if (sparseOffset < 0) { |
| throw new IOException("Corrupted TAR archive. Sparse struct offset contains negative value"); |
| } |
| final long sparseNumbytes = ParsingUtils.parseLongValue(sparseHeaderStrings[i + 1]); |
| if (sparseNumbytes < 0) { |
| throw new IOException("Corrupted TAR archive. Sparse struct numbytes contains negative value"); |
| } |
| sparseHeaders.add(new TarArchiveStructSparse(sparseOffset, sparseNumbytes)); |
| } |
| return Collections.unmodifiableList(sparseHeaders); |
| } |
| |
| /** |
| * Parses an entry name from a buffer. Parsing stops when a NUL is found or the buffer length is reached. |
| * |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @param length The maximum number of bytes to parse. |
| * @return The entry name. |
| */ |
| public static String parseName(final byte[] buffer, final int offset, final int length) { |
| try { |
| return parseName(buffer, offset, length, DEFAULT_ENCODING); |
| } catch (final IOException ex) { // NOSONAR |
| try { |
| return parseName(buffer, offset, length, FALLBACK_ENCODING); |
| } catch (final IOException ex2) { |
| // impossible |
| throw new UncheckedIOException(ex2); // NOSONAR |
| } |
| } |
| } |
| |
| /** |
| * Parses an entry name from a buffer. Parsing stops when a NUL is found or the buffer length is reached. |
| * |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @param length The maximum number of bytes to parse. |
| * @param encoding name of the encoding to use for file names |
| * @since 1.4 |
| * @return The entry name. |
| * @throws IOException on error |
| */ |
| public static String parseName(final byte[] buffer, final int offset, final int length, final ZipEncoding encoding) throws IOException { |
| int len = 0; |
| for (int i = offset; len < length && buffer[i] != 0; i++) { |
| len++; |
| } |
| if (len > 0) { |
| final byte[] b = new byte[len]; |
| System.arraycopy(buffer, offset, b, 0, len); |
| return encoding.decode(b); |
| } |
| return ""; |
| } |
| |
| /** |
| * Parses an octal string from a buffer. |
| * |
| * <p> |
| * Leading spaces are ignored. The buffer must contain a trailing space or NUL, and may contain an additional trailing space or NUL. |
| * </p> |
| * |
| * <p> |
| * The input buffer is allowed to contain all NULs, in which case the method returns 0L (this allows for missing fields). |
| * </p> |
| * |
| * <p> |
| * To work-around some tar implementations that insert a leading NUL this method returns 0 if it detects a leading NUL since Commons Compress 1.4. |
| * </p> |
| * |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @param length The maximum number of bytes to parse - must be at least 2 bytes. |
| * @return The long value of the octal string. |
| * @throws IllegalArgumentException if the trailing space/NUL is missing or if an invalid byte is detected. |
| */ |
| public static long parseOctal(final byte[] buffer, final int offset, final int length) { |
| long result = 0; |
| int end = offset + length; |
| int start = offset; |
| if (length < 2) { |
| throw new IllegalArgumentException("Length " + length + " must be at least 2"); |
| } |
| if (buffer[start] == 0) { |
| return 0L; |
| } |
| // Skip leading spaces |
| while (start < end) { |
| if (buffer[start] != ' ') { |
| break; |
| } |
| start++; |
| } |
| // Trim all trailing NULs and spaces. |
| // The ustar and POSIX tar specs require a trailing NUL or |
| // space but some implementations use the extra digit for big |
| // sizes/uids/gids ... |
| byte trailer = buffer[end - 1]; |
| while (start < end && (trailer == 0 || trailer == ' ')) { |
| end--; |
| trailer = buffer[end - 1]; |
| } |
| for (; start < end; start++) { |
| final byte currentByte = buffer[start]; |
| // CheckStyle:MagicNumber OFF |
| if (currentByte < '0' || currentByte > '7') { |
| throw new IllegalArgumentException(exceptionMessage(buffer, offset, length, start, currentByte)); |
| } |
| result = (result << 3) + (currentByte - '0'); // convert from ASCII |
| // CheckStyle:MagicNumber ON |
| } |
| return result; |
| } |
| |
| /** |
| * Computes the value contained in a byte buffer. If the most significant bit of the first byte in the buffer is set, this bit is ignored and the rest of |
| * the buffer is interpreted as a binary number. Otherwise, the buffer is interpreted as an octal number as per the parseOctal function above. |
| * |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @param length The maximum number of bytes to parse. |
| * @return The long value of the octal or binary string. |
| * @throws IllegalArgumentException if the trailing space/NUL is missing or an invalid byte is detected in an octal number, or if a binary number would |
| * exceed the size of a signed long 64-bit integer. |
| * @since 1.4 |
| */ |
| public static long parseOctalOrBinary(final byte[] buffer, final int offset, final int length) { |
| if ((buffer[offset] & 0x80) == 0) { |
| return parseOctal(buffer, offset, length); |
| } |
| final boolean negative = buffer[offset] == (byte) 0xff; |
| if (length < 9) { |
| return parseBinaryLong(buffer, offset, length, negative); |
| } |
| return parseBinaryBigInteger(buffer, offset, length, negative); |
| } |
| |
| /** |
| * For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map |
| * |
| * <p> |
| * <em>GNU.sparse.map</em>: Map of non-null data chunks. It is a string consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * </p> |
| * <p> |
| * Will internally invoke {@link #parseFromPAX01SparseHeaders} and map IOExceptions to a RzuntimeException, You should use |
| * {@link #parseFromPAX01SparseHeaders} directly instead. |
| * </p> |
| * |
| * @param sparseMap the sparse map string consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * @return sparse headers parsed from sparse map |
| * @deprecated use #parseFromPAX01SparseHeaders instead |
| */ |
| @Deprecated |
| protected static List<TarArchiveStructSparse> parsePAX01SparseHeaders(final String sparseMap) { |
| try { |
| return parseFromPAX01SparseHeaders(sparseMap); |
| } catch (final IOException ex) { |
| throw new UncheckedIOException(ex.getMessage(), ex); |
| } |
| } |
| |
| /** |
| * For PAX Format 1.X: The sparse map itself is stored in the file data block, preceding the actual file data. It consists of a series of decimal numbers |
| * delimited by newlines. The map is padded with nulls to the nearest block boundary. The first number gives the number of entries in the map. Following are |
| * map entries, each one consisting of two numbers giving the offset and size of the data block it describes. |
| * |
| * @param inputStream parsing source. |
| * @param recordSize The size the TAR header |
| * @return sparse headers |
| * @throws IOException if an I/O error occurs. |
| */ |
| protected static List<TarArchiveStructSparse> parsePAX1XSparseHeaders(final InputStream inputStream, final int recordSize) throws IOException { |
| // for 1.X PAX Headers |
| final List<TarArchiveStructSparse> sparseHeaders = new ArrayList<>(); |
| long bytesRead = 0; |
| long[] readResult = readLineOfNumberForPax1X(inputStream); |
| long sparseHeadersCount = readResult[0]; |
| if (sparseHeadersCount < 0) { |
| // overflow while reading number? |
| throw new IOException("Corrupted TAR archive. Negative value in sparse headers block"); |
| } |
| bytesRead += readResult[1]; |
| while (sparseHeadersCount-- > 0) { |
| readResult = readLineOfNumberForPax1X(inputStream); |
| final long sparseOffset = readResult[0]; |
| if (sparseOffset < 0) { |
| throw new IOException("Corrupted TAR archive. Sparse header block offset contains negative value"); |
| } |
| bytesRead += readResult[1]; |
| |
| readResult = readLineOfNumberForPax1X(inputStream); |
| final long sparseNumbytes = readResult[0]; |
| if (sparseNumbytes < 0) { |
| throw new IOException("Corrupted TAR archive. Sparse header block numbytes contains negative value"); |
| } |
| bytesRead += readResult[1]; |
| sparseHeaders.add(new TarArchiveStructSparse(sparseOffset, sparseNumbytes)); |
| } |
| // skip the rest of this record data |
| final long bytesToSkip = recordSize - bytesRead % recordSize; |
| org.apache.commons.io.IOUtils.skip(inputStream, bytesToSkip); |
| return sparseHeaders; |
| } |
| |
| /** |
| * For PAX Format 0.0, the sparse headers(GNU.sparse.offset and GNU.sparse.numbytes) may appear multi times, and they look like: |
| * |
| * <pre> |
| * GNU.sparse.size=size |
| * GNU.sparse.numblocks=numblocks |
| * repeat numblocks times |
| * GNU.sparse.offset=offset |
| * GNU.sparse.numbytes=numbytes |
| * end repeat |
| * </pre> |
| * <p> |
| * For PAX Format 0.1, the sparse headers are stored in a single variable: GNU.sparse.map |
| * </p> |
| * <p> |
| * <em>GNU.sparse.map</em>: Map of non-null data chunks. It is a string consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * </p> |
| * |
| * @param inputStream input stream to read keys and values |
| * @param sparseHeaders used in PAX Format 0.0 & 0.1, as it may appear multiple times, the sparse headers need to be stored in an array, not a map |
| * @param globalPaxHeaders global PAX headers of the tar archive |
| * @return map of PAX headers values found inside the current (local or global) PAX headers tar entry. |
| * @throws IOException if an I/O error occurs. |
| * @deprecated use the four-arg version instead |
| */ |
| @Deprecated |
| protected static Map<String, String> parsePaxHeaders(final InputStream inputStream, final List<TarArchiveStructSparse> sparseHeaders, |
| final Map<String, String> globalPaxHeaders) throws IOException { |
| return parsePaxHeaders(inputStream, sparseHeaders, globalPaxHeaders, -1); |
| } |
| |
| /** |
| * For PAX Format 0.0, the sparse headers(GNU.sparse.offset and GNU.sparse.numbytes) may appear multi times, and they look like: |
| * |
| * <pre> |
| * GNU.sparse.size=size |
| * GNU.sparse.numblocks=numblocks |
| * repeat numblocks times |
| * GNU.sparse.offset=offset |
| * GNU.sparse.numbytes=numbytes |
| * end repeat |
| * </pre> |
| * <p> |
| * For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map |
| * </p> |
| * <p> |
| * <em>GNU.sparse.map</em>: Map of non-null data chunks. It is a string consisting of comma-separated values "offset,size[,offset-1,size-1...]" |
| * </p> |
| * |
| * @param inputStream input stream to read keys and values |
| * @param sparseHeaders used in PAX Format 0.0 & 0.1, as it may appear multiple times, the sparse headers need to be stored in an array, not a map |
| * @param globalPaxHeaders global PAX headers of the tar archive |
| * @param headerSize total size of the PAX header, will be ignored if negative |
| * @return map of PAX headers values found inside the current (local or global) PAX headers tar entry. |
| * @throws IOException if an I/O error occurs. |
| * @since 1.21 |
| */ |
| protected static Map<String, String> parsePaxHeaders(final InputStream inputStream, final List<TarArchiveStructSparse> sparseHeaders, |
| final Map<String, String> globalPaxHeaders, final long headerSize) throws IOException { |
| final Map<String, String> headers = new HashMap<>(globalPaxHeaders); |
| Long offset = null; |
| // Format is "length keyword=value\n"; |
| int totalRead = 0; |
| while (true) { // get length |
| int ch; |
| int len = 0; |
| int read = 0; |
| while ((ch = inputStream.read()) != -1) { |
| read++; |
| totalRead++; |
| if (ch == '\n') { // blank line in header |
| break; |
| } |
| if (ch == ' ') { // End of length string |
| // Get keyword |
| final ByteArrayOutputStream coll = new ByteArrayOutputStream(); |
| while ((ch = inputStream.read()) != -1) { |
| read++; |
| totalRead++; |
| if (totalRead < 0 || headerSize >= 0 && totalRead >= headerSize) { |
| break; |
| } |
| if (ch == '=') { // end of keyword |
| final String keyword = coll.toString(CharsetNames.UTF_8); |
| // Get rest of entry |
| final int restLen = len - read; |
| if (restLen <= 1) { // only NL |
| headers.remove(keyword); |
| } else if (headerSize >= 0 && restLen > headerSize - totalRead) { |
| throw new IOException("Paxheader value size " + restLen + " exceeds size of header record"); |
| } else { |
| final byte[] rest = IOUtils.readRange(inputStream, restLen); |
| final int got = rest.length; |
| if (got != restLen) { |
| throw new IOException("Failed to read Paxheader. Expected " + restLen + " bytes, read " + got); |
| } |
| totalRead += restLen; |
| // Drop trailing NL |
| if (rest[restLen - 1] != '\n') { |
| throw new IOException("Failed to read Paxheader." + "Value should end with a newline"); |
| } |
| final String value = new String(rest, 0, restLen - 1, StandardCharsets.UTF_8); |
| headers.put(keyword, value); |
| |
| // for 0.0 PAX Headers |
| if (keyword.equals(TarGnuSparseKeys.OFFSET)) { |
| if (offset != null) { |
| // previous GNU.sparse.offset header but no numBytes |
| sparseHeaders.add(new TarArchiveStructSparse(offset, 0)); |
| } |
| try { |
| offset = Long.valueOf(value); |
| } catch (final NumberFormatException ex) { |
| throw new IOException("Failed to read Paxheader." + TarGnuSparseKeys.OFFSET + " contains a non-numeric value"); |
| } |
| if (offset < 0) { |
| throw new IOException("Failed to read Paxheader." + TarGnuSparseKeys.OFFSET + " contains negative value"); |
| } |
| } |
| |
| // for 0.0 PAX Headers |
| if (keyword.equals(TarGnuSparseKeys.NUMBYTES)) { |
| if (offset == null) { |
| throw new IOException( |
| "Failed to read Paxheader." + TarGnuSparseKeys.OFFSET + " is expected before GNU.sparse.numbytes shows up."); |
| } |
| final long numbytes = ParsingUtils.parseLongValue(value); |
| if (numbytes < 0) { |
| throw new IOException("Failed to read Paxheader." + TarGnuSparseKeys.NUMBYTES + " contains negative value"); |
| } |
| sparseHeaders.add(new TarArchiveStructSparse(offset, numbytes)); |
| offset = null; |
| } |
| } |
| break; |
| } |
| coll.write((byte) ch); |
| } |
| break; // Processed single header |
| } |
| // COMPRESS-530 : throw if we encounter a non-number while reading length |
| if (ch < '0' || ch > '9') { |
| throw new IOException("Failed to read Paxheader. Encountered a non-number while reading length"); |
| } |
| len *= 10; |
| len += ch - '0'; |
| } |
| if (ch == -1) { // EOF |
| break; |
| } |
| } |
| if (offset != null) { |
| // offset but no numBytes |
| sparseHeaders.add(new TarArchiveStructSparse(offset, 0)); |
| } |
| return headers; |
| } |
| |
| /** |
| * Parses the content of a PAX 1.0 sparse block. |
| * |
| * @since 1.20 |
| * @param buffer The buffer from which to parse. |
| * @param offset The offset into the buffer from which to parse. |
| * @return a parsed sparse struct |
| */ |
| public static TarArchiveStructSparse parseSparse(final byte[] buffer, final int offset) { |
| final long sparseOffset = parseOctalOrBinary(buffer, offset, TarConstants.SPARSE_OFFSET_LEN); |
| final long sparseNumbytes = parseOctalOrBinary(buffer, offset + TarConstants.SPARSE_OFFSET_LEN, TarConstants.SPARSE_NUMBYTES_LEN); |
| return new TarArchiveStructSparse(sparseOffset, sparseNumbytes); |
| } |
| |
| /** |
| * For 1.X PAX Format, the sparse headers are stored in the file data block, preceding the actual file data. It consists of a series of decimal numbers |
| * delimited by newlines. |
| * |
| * @param inputStream the input stream of the tar file |
| * @return the decimal number delimited by '\n', and the bytes read from input stream |
| * @throws IOException |
| */ |
| private static long[] readLineOfNumberForPax1X(final InputStream inputStream) throws IOException { |
| int number; |
| long result = 0; |
| long bytesRead = 0; |
| while ((number = inputStream.read()) != '\n') { |
| bytesRead += 1; |
| if (number == -1) { |
| throw new IOException("Unexpected EOF when reading parse information of 1.X PAX format"); |
| } |
| if (number < '0' || number > '9') { |
| throw new IOException("Corrupted TAR archive. Non-numeric value in sparse headers block"); |
| } |
| result = result * 10 + (number - '0'); |
| } |
| bytesRead += 1; |
| return new long[] { result, bytesRead }; |
| } |
| |
| /** |
| * @since 1.21 |
| */ |
| static List<TarArchiveStructSparse> readSparseStructs(final byte[] buffer, final int offset, final int entries) throws IOException { |
| final List<TarArchiveStructSparse> sparseHeaders = new ArrayList<>(); |
| for (int i = 0; i < entries; i++) { |
| try { |
| final TarArchiveStructSparse sparseHeader = parseSparse(buffer, |
| offset + i * (TarConstants.SPARSE_OFFSET_LEN + TarConstants.SPARSE_NUMBYTES_LEN)); |
| if (sparseHeader.getOffset() < 0) { |
| throw new IOException("Corrupted TAR archive, sparse entry with negative offset"); |
| } |
| if (sparseHeader.getNumbytes() < 0) { |
| throw new IOException("Corrupted TAR archive, sparse entry with negative numbytes"); |
| } |
| sparseHeaders.add(sparseHeader); |
| } catch (final IllegalArgumentException ex) { |
| // thrown internally by parseOctalOrBinary |
| throw new IOException("Corrupted TAR archive, sparse entry is invalid", ex); |
| } |
| } |
| return Collections.unmodifiableList(sparseHeaders); |
| } |
| |
| /** |
| * Wikipedia <a href="https://en.wikipedia.org/wiki/Tar_(computing)#File_header">says</a>: <blockquote> The checksum is calculated by taking the sum of the |
| * unsigned byte values of the header block with the eight checksum bytes taken to be ASCII spaces (decimal value 32). It is stored as a six digit octal |
| * number with leading zeroes followed by a NUL and then a space. Various implementations do not adhere to this format. For better compatibility, ignore |
| * leading and trailing whitespace, and get the first six digits. In addition, some historic tar implementations treated bytes as signed. Implementations |
| * typically calculate the checksum both ways, and treat it as good if either the signed or unsigned sum matches the included checksum. </blockquote> |
| * <p> |
| * The return value of this method should be treated as a best-effort heuristic rather than an absolute and final truth. The checksum verification logic may |
| * well evolve over time as more special cases are encountered. |
| * </p> |
| * |
| * @param header tar header |
| * @return whether the checksum is reasonably good |
| * @see <a href="https://issues.apache.org/jira/browse/COMPRESS-191">COMPRESS-191</a> |
| * @since 1.5 |
| */ |
| public static boolean verifyCheckSum(final byte[] header) { |
| final long storedSum = parseOctal(header, TarConstants.CHKSUM_OFFSET, TarConstants.CHKSUMLEN); |
| long unsignedSum = 0; |
| long signedSum = 0; |
| for (int i = 0; i < header.length; i++) { |
| byte b = header[i]; |
| if (TarConstants.CHKSUM_OFFSET <= i && i < TarConstants.CHKSUM_OFFSET + TarConstants.CHKSUMLEN) { |
| b = ' '; |
| } |
| unsignedSum += 0xff & b; |
| signedSum += b; |
| } |
| return storedSum == unsignedSum || storedSum == signedSum; |
| } |
| |
| /** Prevents instantiation. */ |
| private TarUtils() { |
| } |
| |
| } |
