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GT-2912 - fix CPIO filesystem infinite loop when opening bad file.

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Also improve "getinfo" to show info elements that it should have been
showing but were lost.
This commit is contained in:
dev747368 2019-06-13 13:53:02 -04:00
parent 7bece24cae
commit 56a53cb7f7
1 changed files with 57 additions and 51 deletions
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96
Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/cpio/CpioFileSystem.java
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@ -48,32 +48,19 @@ public class CpioFileSystem extends GFileSystemBase {
public void open(TaskMonitor monitor) throws IOException, CryptoException, CancelledException {
monitor.setMessage("Opening CPIO...");
byte[] bytes = provider.readBytes(0, provider.length());
InputStream inputStream = new ByteArrayInputStream(bytes);
try (CpioArchiveInputStream cpioInputStream = new CpioArchiveInputStream(inputStream)) {
while (!monitor.isCancelled()) {
/* TODO is this check needed?
if ( cpioInputStream.available() == 0 ) {
break;
}
*/
try {
CpioArchiveEntry entry = cpioInputStream.getNextCPIOEntry();
if (entry == null) {
break;
}
readEntryContents(cpioInputStream, monitor);//ignore contents now, but it must be read from stream
try (CpioArchiveInputStream cpioInputStream =
new CpioArchiveInputStream(provider.getInputStream(0))) {
CpioArchiveEntry entry;
while ((entry = cpioInputStream.getNextCPIOEntry()) != null) {
skipEntryContents(cpioInputStream, monitor);
storeEntry(entry, monitor);
}
}
catch (EOFException e) {
break;
// silently ignore EOFExceptions
}
catch (Exception e) {
FSUtilities.displayException(this, null, "Error While Opening CPIO",
e.getMessage(), e);
}
}
FSUtilities.displayException(this, null, "Error While Opening CPIO", e.getMessage(), e);
}
}
@ -112,22 +99,32 @@ public class CpioFileSystem extends GFileSystemBase {
StringBuilder buffer = new StringBuilder();
try {
buffer.append("Name: " + entry.getName() + "\n");
buffer.append("Checksum: " + Long.toHexString(entry.getChksum()) + "\n");
buffer.append("Format: " + Long.toHexString(entry.getFormat()) + "\n");
buffer.append("GID: " + Long.toHexString(entry.getGID()) + "\n");
buffer.append("Inode: " + Long.toHexString(entry.getInode()) + "\n");
buffer.append("Last Modified: " + entry.getLastModifiedDate() + "\n");
buffer.append("Links: " + Long.toHexString(entry.getNumberOfLinks()) + "\n");
buffer.append("Mode: " + Long.toHexString(entry.getMode()) + "\n");
buffer.append("Remote Device: " + Long.toHexString(entry.getRemoteDevice()) + "\n");
buffer.append("Size: " + Long.toHexString(entry.getSize()) + "\n");
buffer.append("Time: " + new Date(entry.getTime()) + "\n");
buffer.append("UID: " + Long.toHexString(entry.getUID()) + "\n");
buffer.append("Device ID: " + Long.toHexString(entry.getDevice()) + "\n");
}
catch (Exception e) {
// ignore
}
try {
buffer.append("Device ID: " + Long.toHexString(entry.getDevice()) + "\n");
buffer.append("Remote Device: " + Long.toHexString(entry.getRemoteDevice()) + "\n");
}
catch (Exception e) {
// ignore old format missing exception
}
try {
buffer.append("Checksum: " + Long.toHexString(entry.getChksum()) + "\n");
}
catch (Exception e) {
// ignore new format missing exception
}
return buffer.toString();
}
@ -138,28 +135,22 @@ public class CpioFileSystem extends GFileSystemBase {
if (!fileEntry.isRegularFile()) {
throw new IOException("CPIO entry " + file.getName() + " is not a regular file.");
}
byte[] bytes = provider.readBytes(0, provider.length());
InputStream inputStream = new ByteArrayInputStream(bytes);
CpioArchiveInputStream cpioInputStream = new CpioArchiveInputStream(inputStream);
try {
while (true) {
if (monitor.isCancelled()) {
break;
}
CpioArchiveEntry entry = cpioInputStream.getNextCPIOEntry();
if (entry == null) {
break;
try (CpioArchiveInputStream cpioInputStream =
new CpioArchiveInputStream(provider.getInputStream(0));) {
CpioArchiveEntry entry;
while ((entry = cpioInputStream.getNextCPIOEntry()) != null) {
if (!entry.equals(fileEntry)) {
skipEntryContents(cpioInputStream, monitor);
}
else {
byte[] entryBytes = readEntryContents(cpioInputStream, monitor);
if (entry.equals(fileEntry)) {
return new ByteArrayInputStream(entryBytes);
}
}
}
catch (IllegalArgumentException e) {//unknown MODES..
}
finally {
cpioInputStream.close();
catch (IllegalArgumentException e) {
//unknown MODES..
}
return null;
}
@ -189,18 +180,33 @@ public class CpioFileSystem extends GFileSystemBase {
}
private byte[] readEntryContents(CpioArchiveInputStream cpioInputStream, TaskMonitor monitor)
throws IOException {
throws IOException, CancelledException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] buffer = new byte[64 * 1024];
while (true) {
if (monitor.isCancelled()) {
return null;
throw new CancelledException();
}
int b = cpioInputStream.read();
if (b == -1) {
int bytesRead = cpioInputStream.read(buffer);
if (bytesRead <= 0) {
break;
}
out.write(b);
out.write(buffer, 0, bytesRead);
}
return out.toByteArray();
}
private void skipEntryContents(CpioArchiveInputStream cpioInputStream, TaskMonitor monitor)
throws IOException, CancelledException {
byte[] buffer = new byte[64 * 1024];
while (true) {
if (monitor.isCancelled()) {
throw new CancelledException();
}
int bytesRead = cpioInputStream.read(buffer);
if (bytesRead <= 0) {
break;
}
}
}
}