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19 package org.apache.commons.compress.archivers.ar;
20
21 import java.io.EOFException;
22 import java.io.IOException;
23 import java.io.InputStream;
24 import java.nio.charset.StandardCharsets;
25 import java.util.Arrays;
26 import java.util.regex.Pattern;
27
28 import org.apache.commons.compress.archivers.ArchiveInputStream;
29 import org.apache.commons.compress.utils.ArchiveUtils;
30 import org.apache.commons.compress.utils.IOUtils;
31 import org.apache.commons.compress.utils.ParsingUtils;
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38 public class ArArchiveInputStream extends ArchiveInputStream<ArArchiveEntry> {
39
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41 private static final int NAME_OFFSET = 0;
42 private static final int NAME_LEN = 16;
43 private static final int LAST_MODIFIED_OFFSET = NAME_LEN;
44
45 private static final int LAST_MODIFIED_LEN = 12;
46
47 private static final int USER_ID_OFFSET = LAST_MODIFIED_OFFSET + LAST_MODIFIED_LEN;
48
49 private static final int USER_ID_LEN = 6;
50
51 private static final int GROUP_ID_OFFSET = USER_ID_OFFSET + USER_ID_LEN;
52 private static final int GROUP_ID_LEN = 6;
53 private static final int FILE_MODE_OFFSET = GROUP_ID_OFFSET + GROUP_ID_LEN;
54 private static final int FILE_MODE_LEN = 8;
55 private static final int LENGTH_OFFSET = FILE_MODE_OFFSET + FILE_MODE_LEN;
56 private static final int LENGTH_LEN = 10;
57 static final String BSD_LONGNAME_PREFIX = "#1/";
58 private static final int BSD_LONGNAME_PREFIX_LEN = BSD_LONGNAME_PREFIX.length();
59 private static final Pattern BSD_LONGNAME_PATTERN = Pattern.compile("^" + BSD_LONGNAME_PREFIX + "\\d+");
60 private static final String GNU_STRING_TABLE_NAME = "//";
61 private static final Pattern GNU_LONGNAME_PATTERN = Pattern.compile("^/\\d+");
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85 private static boolean isBSDLongName(final String name) {
86 return name != null && BSD_LONGNAME_PATTERN.matcher(name).matches();
87 }
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103 private static boolean isGNUStringTable(final String name) {
104 return GNU_STRING_TABLE_NAME.equals(name);
105 }
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114 public static boolean matches(final byte[] signature, final int length) {
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117 return length >= 8 &&
118 signature[0] == 0x21 &&
119 signature[1] == 0x3c &&
120 signature[2] == 0x61 &&
121 signature[3] == 0x72 &&
122 signature[4] == 0x63 &&
123 signature[5] == 0x68 &&
124 signature[6] == 0x3e &&
125 signature[7] == 0x0a;
126
127 }
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129 private long offset;
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131 private boolean closed;
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136 private ArArchiveEntry currentEntry;
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139 private byte[] namebuffer;
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144 private long entryOffset = -1;
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147 private final byte[] metaData = new byte[NAME_LEN + LAST_MODIFIED_LEN + USER_ID_LEN + GROUP_ID_LEN + FILE_MODE_LEN + LENGTH_LEN];
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154 public ArArchiveInputStream(final InputStream inputStream) {
155 super(inputStream, StandardCharsets.US_ASCII.name());
156 }
157
158 private int asInt(final byte[] byteArray, final int offset, final int len) throws IOException {
159 return asInt(byteArray, offset, len, 10, false);
160 }
161
162 private int asInt(final byte[] byteArray, final int offset, final int len, final boolean treatBlankAsZero) throws IOException {
163 return asInt(byteArray, offset, len, 10, treatBlankAsZero);
164 }
165
166 private int asInt(final byte[] byteArray, final int offset, final int len, final int base) throws IOException {
167 return asInt(byteArray, offset, len, base, false);
168 }
169
170 private int asInt(final byte[] byteArray, final int offset, final int len, final int base, final boolean treatBlankAsZero) throws IOException {
171 final String string = ArchiveUtils.toAsciiString(byteArray, offset, len).trim();
172 if (string.isEmpty() && treatBlankAsZero) {
173 return 0;
174 }
175 return ParsingUtils.parseIntValue(string, base);
176 }
177
178 private long asLong(final byte[] byteArray, final int offset, final int len) throws IOException {
179 return ParsingUtils.parseLongValue(ArchiveUtils.toAsciiString(byteArray, offset, len).trim());
180 }
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187 @Override
188 public void close() throws IOException {
189 if (!closed) {
190 closed = true;
191 in.close();
192 }
193 currentEntry = null;
194 }
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202 private String getBSDLongName(final String bsdLongName) throws IOException {
203 final int nameLen = ParsingUtils.parseIntValue(bsdLongName.substring(BSD_LONGNAME_PREFIX_LEN));
204 final byte[] name = IOUtils.readRange(in, nameLen);
205 final int read = name.length;
206 trackReadBytes(read);
207 if (read != nameLen) {
208 throw new EOFException(bsdLongName);
209 }
210 return ArchiveUtils.toAsciiString(name);
211 }
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220 private String getExtendedName(final int offset) throws IOException {
221 if (namebuffer == null) {
222 throw new IOException("Cannot process GNU long file name as no // record was found");
223 }
224 for (int i = offset; i < namebuffer.length; i++) {
225 if (namebuffer[i] == '\012' || namebuffer[i] == 0) {
226
227 if (i == 0) {
228 break;
229 }
230 if (namebuffer[i - 1] == '/') {
231 i--;
232 }
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234 if (i - offset > 0) {
235 return ArchiveUtils.toAsciiString(namebuffer, offset, i - offset);
236 }
237 break;
238 }
239 }
240 throw new IOException("Failed to read entry: " + offset);
241 }
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250 @Deprecated
251 public ArArchiveEntry getNextArEntry() throws IOException {
252 if (currentEntry != null) {
253 final long entryEnd = entryOffset + currentEntry.getLength();
254 final long skipped = org.apache.commons.io.IOUtils.skip(in, entryEnd - offset);
255 trackReadBytes(skipped);
256 currentEntry = null;
257 }
258 if (offset == 0) {
259 final byte[] expected = ArchiveUtils.toAsciiBytes(ArArchiveEntry.HEADER);
260 final byte[] realized = IOUtils.readRange(in, expected.length);
261 final int read = realized.length;
262 trackReadBytes(read);
263 if (read != expected.length) {
264 throw new IOException("Failed to read header. Occurred at byte: " + getBytesRead());
265 }
266 if (!Arrays.equals(expected, realized)) {
267 throw new IOException("Invalid header " + ArchiveUtils.toAsciiString(realized));
268 }
269 }
270 if (offset % 2 != 0) {
271 if (in.read() < 0) {
272
273 return null;
274 }
275 trackReadBytes(1);
276 }
277 {
278 final int read = IOUtils.readFully(in, metaData);
279 trackReadBytes(read);
280 if (read == 0) {
281 return null;
282 }
283 if (read < metaData.length) {
284 throw new IOException("Truncated ar archive");
285 }
286 }
287 {
288 final byte[] expected = ArchiveUtils.toAsciiBytes(ArArchiveEntry.TRAILER);
289 final byte[] realized = IOUtils.readRange(in, expected.length);
290 final int read = realized.length;
291 trackReadBytes(read);
292 if (read != expected.length) {
293 throw new IOException("Failed to read entry trailer. Occurred at byte: " + getBytesRead());
294 }
295 if (!Arrays.equals(expected, realized)) {
296 throw new IOException("Invalid entry trailer. not read the content? Occurred at byte: " + getBytesRead());
297 }
298 }
299
300 entryOffset = offset;
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303 String temp = ArchiveUtils.toAsciiString(metaData, NAME_OFFSET, NAME_LEN).trim();
304 if (isGNUStringTable(temp)) {
305 currentEntry = readGNUStringTable(metaData, LENGTH_OFFSET, LENGTH_LEN);
306 return getNextArEntry();
307 }
308 long len;
309 try {
310 len = asLong(metaData, LENGTH_OFFSET, LENGTH_LEN);
311 } catch (final NumberFormatException ex) {
312 throw new IOException("Broken archive, unable to parse ar_size field as a number", ex);
313 }
314 if (temp.endsWith("/")) {
315 temp = temp.substring(0, temp.length() - 1);
316 } else if (isGNULongName(temp)) {
317 final int off = ParsingUtils.parseIntValue(temp.substring(1));
318 temp = getExtendedName(off);
319 } else if (isBSDLongName(temp)) {
320 temp = getBSDLongName(temp);
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324 final int nameLen = temp.length();
325 len -= nameLen;
326 entryOffset += nameLen;
327 }
328 if (len < 0) {
329 throw new IOException("broken archive, entry with negative size");
330 }
331 try {
332 currentEntry = new ArArchiveEntry(temp, len, asInt(metaData, USER_ID_OFFSET, USER_ID_LEN, true),
333 asInt(metaData, GROUP_ID_OFFSET, GROUP_ID_LEN, true), asInt(metaData, FILE_MODE_OFFSET, FILE_MODE_LEN, 8),
334 asLong(metaData, LAST_MODIFIED_OFFSET, LAST_MODIFIED_LEN));
335 return currentEntry;
336 } catch (final NumberFormatException ex) {
337 throw new IOException("Broken archive, unable to parse entry metadata fields as numbers", ex);
338 }
339 }
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346 @Override
347 public ArArchiveEntry getNextEntry() throws IOException {
348 return getNextArEntry();
349 }
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356 private boolean isGNULongName(final String name) {
357 return name != null && GNU_LONGNAME_PATTERN.matcher(name).matches();
358 }
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365 @Override
366 public int read(final byte[] b, final int off, final int len) throws IOException {
367 if (len == 0) {
368 return 0;
369 }
370 if (currentEntry == null) {
371 throw new IllegalStateException("No current ar entry");
372 }
373 final long entryEnd = entryOffset + currentEntry.getLength();
374 if (len < 0 || offset >= entryEnd) {
375 return -1;
376 }
377 final int toRead = (int) Math.min(len, entryEnd - offset);
378 final int ret = this.in.read(b, off, toRead);
379 trackReadBytes(ret);
380 return ret;
381 }
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388 private ArArchiveEntry readGNUStringTable(final byte[] length, final int offset, final int len) throws IOException {
389 final int bufflen;
390 try {
391 bufflen = asInt(length, offset, len);
392 } catch (final NumberFormatException ex) {
393 throw new IOException("Broken archive, unable to parse GNU string table length field as a number", ex);
394 }
395 namebuffer = IOUtils.readRange(in, bufflen);
396 final int read = namebuffer.length;
397 trackReadBytes(read);
398 if (read != bufflen) {
399 throw new IOException("Failed to read complete // record: expected=" + bufflen + " read=" + read);
400 }
401 return new ArArchiveEntry(GNU_STRING_TABLE_NAME, bufflen);
402 }
403
404 private void trackReadBytes(final long read) {
405 count(read);
406 if (read > 0) {
407 offset += read;
408 }
409 }
410 }