*
* @author Roland Haeder <webmaster@ship-simu.org>
* @version 0.0.0
- * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2011 Hub Developer Team
+ * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 Hub Developer Team
* @license GNU GPL 3.0 or any newer version
* @link http://www.ship-simu.org
*
* Stacker for chunks with final EOP
*/
const STACKER_NAME_CHUNKS_WITH_FINAL_EOP = 'final_chunks';
+ const STACKER_NAME_CHUNKS_WITHOUT_FINAL = 'pending_chunks';
+ const STACKER_NAME_ASSEMBLED_RAW_DATA = 'chunk_raw_data';
+
+ /**
+ * Chunk splits:
+ * 0 = Hash
+ * 1 = Serial number
+ * 2 = Raw data
+ */
+ const CHUNK_SPLITS_INDEX_HASH = 0;
+ const CHUNK_SPLITS_INDEX_SERIAL = 1;
+ const CHUNK_SPLITS_INDEX_RAW_DATA = 2;
+
+ /**
+ * The final array for assembling the original package back together
+ */
+ private $finalPackageChunks = array();
+
+ /**
+ * Array of chunk hashes
+ */
+ private $chunkHashes = array();
+
+ /**
+ * Raw EOP chunk data in an array:
+ *
+ * 0 = Final hash,
+ * 1 = Hash of last chunk
+ */
+ private $eopChunk = array();
+
+ /**
+ * Raw package data
+ */
+ private $rawPackageData = '';
/**
* Protected constructor
// Set handler name
$this->setHandlerName('chunk');
+
+ // Initialize handler
+ $this->initHandler();
}
/**
$stackerInstance = ObjectFactory::createObjectByConfiguredName('chunk_handler_stacker_class');
// Init all stacker
- $stackerInstance->initStacker(self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP);
+ $stackerInstance->initStacks(array(
+ self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP,
+ self::STACKER_NAME_CHUNKS_WITHOUT_FINAL,
+ self::STACKER_NAME_ASSEMBLED_RAW_DATA
+ ));
// Set the stacker in this handler
$handlerInstance->setStackerInstance($stackerInstance);
// ... and set it in this handler
$handlerInstance->setCryptoInstance($cryptoInstance);
+ // Get a fragmenter instance for later verification of serial numbers (e.g. if all are received)
+ $fragmenterInstance = FragmenterFactory::createFragmenterInstance('package');
+
+ // Set it in this handler
+ $handlerInstance->setFragmenterInstance($fragmenterInstance);
+
// Return the prepared instance
return $handlerInstance;
}
+ /**
+ * Initializes the handler
+ *
+ * @return void
+ */
+ private function initHandler () {
+ // Init finalPackageChunks
+ $this->finalPackageChunks = array(
+ // Array for package content
+ 'content' => array(),
+ // ... and for the hashes
+ 'hashes' => array(),
+ // ... marker for that the final array is complete for assembling all chunks
+ 'is_complete' => FALSE,
+ // ... steps done to assemble all chunks
+ 'assemble_steps' => 0,
+ );
+
+ // ... chunkHashes:
+ $this->chunkHashes = array();
+
+ // ... eopChunk:
+ $this->eopChunk = array(
+ 0 => 'INVALID',
+ 1 => 'INVALID',
+ );
+ }
+
+ /**
+ * Checks whether the hash generated from package content is the same ("valid") as given
+ *
+ * @param $chunkSplits An array from a splitted chunk
+ * @return $isValid Whether the hash is "valid"
+ */
+ private function isChunkHashValid (array $chunkSplits) {
+ // Now hash the raw data again
+ $chunkHash = $this->getCryptoInstance()->hashString($chunkSplits[self::CHUNK_SPLITS_INDEX_RAW_DATA], $chunkSplits[self::CHUNK_SPLITS_INDEX_HASH], FALSE);
+
+ // Debug output
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: chunkHash=' . $chunkHash . ',chunkSplits[chunk_hash]=' . $chunkSplits[self::CHUNK_SPLITS_INDEX_HASH] . ',chunkSplits[serial]=' . $chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL] . ',chunkSplits[raw_data]=' . $chunkSplits[self::CHUNK_SPLITS_INDEX_RAW_DATA]);
+
+ // Check it
+ $isValid = ($chunkSplits[self::CHUNK_SPLITS_INDEX_HASH] === $chunkHash);
+
+ // ... and return it
+ return $isValid;
+ }
+
+ /**
+ * Checks whether the given serial number is valid
+ *
+ * @param $serialNumber A serial number from a chunk
+ * @return $isValid Whether the serial number is valid
+ */
+ private function isSerialNumberValid ($serialNumber) {
+ // Check it
+ $isValid = ((strlen($serialNumber) == PackageFragmenter::MAX_SERIAL_LENGTH) && ($this->hexval($serialNumber, FALSE) === $serialNumber));
+
+ // Return result
+ return $isValid;
+ }
+
+ /**
+ * Adds the chunk to the final array which will be used for the final step
+ * which will be to assemble all chunks back to the original package content
+ * and for the final hash check.
+ *
+ * This method may throw an exception if a chunk with the same serial number
+ * has already been added to avoid mixing chunks from different packages.
+ *
+ * @param $chunkSplits An array from a splitted chunk
+ * @return void
+ */
+ private function addChunkToFinalArray (array $chunkSplits) {
+ // Is the serial number (index 1) already been added?
+ if (isset($this->finalPackageChunks[$chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL]])) {
+ // Then throw an exception
+ throw new ChunkAlreadyAssembledException(array($this, $chunkSplits), self::EXCEPTION_CHUNK_ALREADY_ASSEMBLED);
+ } // END - if
+
+ // Debug message
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: serialNumber=' . $chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL] . ',hash=' . $chunkSplits[self::CHUNK_SPLITS_INDEX_HASH]);
+
+ // Add the chunk data (index 2) to the final array and use the serial number as index
+ $this->finalPackageChunks['content'][$chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL]] = $chunkSplits[self::CHUNK_SPLITS_INDEX_RAW_DATA];
+
+ // ... and the hash as well
+ $this->finalPackageChunks['hashes'][$chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL]] = $chunkSplits[self::CHUNK_SPLITS_INDEX_HASH];
+ }
+
+ /**
+ * Marks the final array as completed, do only this if you really have all
+ * chunks together including EOP and "hash chunk".
+ *
+ * @return void
+ */
+ private function markFinalArrayAsCompleted () {
+ /*
+ * As for now, just set the array element. If any further steps are
+ * being added, this should always be the last step.
+ */
+ $this->finalPackageChunks['is_complete'] = TRUE;
+ }
+
+ /**
+ * Sorts the chunks array by using the serial number as a sorting key. In
+ * most situations a call of ksort() is enough to accomblish this. So this
+ * method may only call ksort() on the chunks array.
+ *
+ * This method sorts 'content' and 'hashes' so both must have used the
+ * serial numbers as array indexes.
+ *
+ * @return void
+ */
+ private function sortChunksArray () {
+ // Sort 'content' first
+ ksort($this->finalPackageChunks['content']);
+
+ // ... then 'hashes'
+ ksort($this->finalPackageChunks['hashes']);
+ }
+
+ /**
+ * Prepares the package assemble by removing last chunks (last shall be
+ * hash chunk, pre-last shall be EOP chunk) and verify that all serial
+ * numbers are valid (same as PackageFragmenter class would generate).
+ *
+ * @return void
+ */
+ private function preparePackageAssmble () {
+ // Make sure both arrays have same count (this however should always be TRUE)
+ assert(count($this->finalPackageChunks['hashes']) == count($this->finalPackageChunks['content']));
+ //* DIE: */ exit(__METHOD__ . ':finalPackageChunks='.print_r($this->finalPackageChunks['content'], TRUE));
+
+ /*
+ * Remove last element (hash chunk) from 'hashes'. This hash will never
+ * be needed, so ignore it.
+ */
+ array_pop($this->finalPackageChunks['hashes']);
+
+ // ... and from 'content' as well but save it for later use
+ $this->chunkHashes = explode(PackageFragmenter::CHUNK_HASH_SEPARATOR, substr(array_pop($this->finalPackageChunks['content']), strlen(PackageFragmenter::HASH_CHUNK_IDENTIFIER)));
+
+ // Remove EOP chunk and keep a copy of it
+ array_pop($this->finalPackageChunks['hashes']);
+ $this->eopChunk = explode(PackageFragmenter::CHUNK_HASH_SEPARATOR, substr(array_pop($this->finalPackageChunks['content']), strlen(PackageFragmenter::END_OF_PACKAGE_IDENTIFIER)));
+
+ // Verify all serial numbers
+ $this->verifyChunkSerialNumbers();
+ }
+
+ /**
+ * Verifies all chunk serial numbers by using a freshly initialized
+ * fragmenter instance. Do ALWAYS sort the array and array_pop() the hash
+ * chunk before calling this method to avoid re-requests of many chunks.
+ *
+ * @return void
+ */
+ private function verifyChunkSerialNumbers () {
+ // Reset the serial number generator
+ $this->getFragmenterInstance()->resetSerialNumber();
+
+ // "Walk" through all (content) chunks
+ foreach ($this->finalPackageChunks['content'] as $serialNumber => $content) {
+ // Get next serial number
+ $nextSerial = $this->getFragmenterInstance()->getNextHexSerialNumber();
+
+ // Debug output
+ //* NOISY-DEBUG */ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: serialNumber=' . $serialNumber . ',nextSerial=' . $nextSerial);
+
+ // Is it not the same? Then re-request it
+ if ($serialNumber != $nextSerial) {
+ // This is invalid, so remove it
+ unset($this->finalPackageChunks['content'][$serialNumber]);
+ unset($this->finalPackageChunks['hashes'][$serialNumber]);
+
+ // And re-request it with valid serial number (and hash chunk)
+ $this->rerequestChunkBySerialNumber($nextSerial);
+ } // END - if
+ } // END - foreach
+ }
+
+ /**
+ * Assembles and verifies ("final check") chunks back together to the
+ * original package (raw data for the start). This method should only be
+ * called AFTER the EOP and final-chunk chunk have been removed.
+ *
+ * @return void
+ */
+ private function assembleAllChunksToPackage () {
+ // If chunkHashes is not filled, don't continue
+ assert(count($this->chunkHashes) > 0);
+
+ // Init raw package data string
+ $this->rawPackageData = '';
+
+ // That went well, so start assembling all chunks
+ foreach ($this->finalPackageChunks['content'] as $serialNumber => $content) {
+ // Debug message
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: serialNumber=' . $serialNumber . ' - validating ...');
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('finalPackageChunks=' . print_r($this->finalPackageChunks, TRUE) . 'chunkHashes=' . print_r($this->chunkHashes, TRUE));
+
+ // Is this chunk valid? This should be the case
+ assert($this->isChunkHashValid(array(
+ self::CHUNK_SPLITS_INDEX_HASH => $this->finalPackageChunks['hashes'][$serialNumber],
+ self::CHUNK_SPLITS_INDEX_RAW_DATA => $content
+ )));
+
+ // ... and is also in the hash chunk?
+ assert(in_array($this->finalPackageChunks['hashes'][$serialNumber], $this->chunkHashes));
+
+ // Verification okay, add it to the raw data
+ $this->rawPackageData .= $content;
+ } // END - foreach
+
+ // Debug output
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: eopChunk[1]=' . $this->eopChunk[1] . ',' . chr(10) . 'index=' . (count($this->chunkHashes) - 2) . ',' . chr(10) . 'chunkHashes='.print_r($this->chunkHashes, TRUE));
+
+ // The last chunk hash must match with the one from eopChunk[1]
+ assert($this->eopChunk[1] == $this->chunkHashes[count($this->chunkHashes) - 2]);
+ }
+
+ /**
+ * Verifies the finally assembled raw package data by comparing it against
+ * the final hash.
+ *
+ * @return void
+ */
+ private function verifyRawPackageData () {
+ // Hash the raw package data for final verification
+ $finalHash = $this->getCryptoInstance()->hashString($this->rawPackageData, $this->eopChunk[0], FALSE);
+
+ // Is it the same?
+ assert($finalHash == $this->eopChunk[0]);
+ }
+
/**
* Adds all chunks if the last one verifies as a 'final chunk'.
*
* @throws FinalChunkVerificationException If the final chunk does not start with 'EOP:'
*/
public function addAllChunksWithFinal (array $chunks) {
- // Validate final chunk
- if (!$this->isValidFinalChunk($chunks)) {
+ // Try to validate the final chunk
+ try {
+ // Validate final chunk
+ $this->isValidFinalChunk($chunks);
+ } catch (AssertionException $e) {
// Last chunk is not valid
- throw new FinalChunkVerificationException(array($this, $chunks), BaseListener::EXCEPTION_FINAL_CHUNK_VERIFICATION);
- } // END - if
+ throw new FinalChunkVerificationException(array($this, $chunks, $e), BaseListener::EXCEPTION_FINAL_CHUNK_VERIFICATION);
+ }
+
+ // Do we have some pending chunks (no final)?
+ while (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_CHUNKS_WITHOUT_FINAL)) {
+ // Then get it first and add it before the EOP chunks
+ array_unshift($chunks, $this->getStackerInstance()->popNamed(self::STACKER_NAME_CHUNKS_WITHOUT_FINAL));
+ } // END - while
// Add all chunks to the FIFO stacker
foreach ($chunks as $chunk) {
} // END - foreach
}
+ /**
+ * Adds all chunks and wait for more (e.g. incomplete transmission)
+ *
+ * @param $chunks An array with chunks, the last one should be a 'final'
+ * @return void
+ */
+ public function addAllChunksWait (array $chunks) {
+ // Add all chunks to the FIFO stacker
+ foreach ($chunks as $chunk) {
+ // Add the chunk
+ $this->getStackerInstance()->pushNamed(self::STACKER_NAME_CHUNKS_WITHOUT_FINAL, $chunk);
+ } // END - foreach
+ }
+
/**
* Checks whether unhandled chunks are available
*
* @return $unhandledChunks Whether unhandled chunks are left
*/
- public function ifUnhandledChunksAvailable () {
+ public function ifUnhandledChunksWithFinalAvailable () {
// Simply check if the stacker is not empty
- $unhandledChunks = $this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP) === false;
+ $unhandledChunks = $this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP) === FALSE;
// Return result
return $unhandledChunks;
*
* @return void
*/
- public function handleAvailableChunks () {
+ public function handleAvailableChunksWithFinal () {
// First check if there are undhandled chunks available
- assert($this->ifUnhandledChunksAvailable());
+ assert($this->ifUnhandledChunksWithFinalAvailable());
// Get an entry from the stacker
$chunk = $this->getStackerInstance()->popNamed(self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP);
*/
assert(count($chunkSplits) == 3);
- // Now hash the raw data again
- $chunkHash = $this->getCryptoInstance()->hashString($chunkSplits[2], $chunkSplits[0], false);
+ // Is the generated hash from data same ("valid") as given hash?
+ if (!$this->isChunkHashValid($chunkSplits)) {
+ // Do some logging
+ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: Chunk content is not validating against given hash.');
- // Debug output
- /* NOISY-DEBUG: */ $this->debugOutput('CHUNK-HANDLER: chunkHash=' . $chunkHash . ',chunkSplits[0]=' . $chunkSplits[0] . ',chunkSplits[1]=' . $chunkSplits[1]);
-
- // Is it the same?
- if ($chunkSplits[0] != $chunkHash) {
// Re-request this chunk (trust the hash in index # 0)
$this->rerequestChunkBySplitsArray($chunkSplits);
// Don't process this chunk
return;
} // END - if
- die('chunk=' . $chunk . chr(10));
+
+ // Is the serial number valid (chars 0-9, length equals PackageFragmenter::MAX_SERIAL_LENGTH)?
+ if (!$this->isSerialNumberValid($chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL])) {
+ // Do some logging
+ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: Chunk serial number ' . $chunkSplits[self::CHUNK_SPLITS_INDEX_SERIAL] . ' for hash ' . $chunkSplits[self::CHUNK_SPLITS_INDEX_HASH] . ' is invalid.');
+
+ // Re-request this chunk
+ $this->rerequestChunkBySplitsArray($chunkSplits);
+
+ // Don't process this chunk
+ return;
+ } // END - if
+
+ /*
+ * It is now known that (as long as the hash algorithm has no
+ * collisions) the content is the same as the sender sends it to this
+ * peer.
+ *
+ * And also the serial number is valid (basicly) at this point. Now the
+ * chunk can be added to the final array.
+ */
+ $this->addChunkToFinalArray($chunkSplits);
+
+ // Is the stack now empty?
+ if ($this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_CHUNKS_WITH_FINAL_EOP)) {
+ // Then mark the final array as complete
+ $this->markFinalArrayAsCompleted();
+ } // END - if
+ }
+
+ /**
+ * Checks whether unassembled chunks are available (ready) in final array
+ *
+ * @return $unassembledChunksAvailable Whether unassembled chunks are available
+ */
+ public function ifUnassembledChunksAvailable () {
+ // For now do only check the array element 'is_complete'
+ $unassembledChunksAvailable = ($this->finalPackageChunks['is_complete'] === TRUE);
+
+ // Return status
+ return $unassembledChunksAvailable;
+ }
+
+ /**
+ * Assembles all chunks (except EOP and "hash chunk") back together to the original package data.
+ *
+ * This is done by the following steps:
+ *
+ * 1) Sort the final array with ksort(). This will bring the "hash
+ * chunk" up to the last array index and the EOP chunk to the
+ * pre-last array index
+ * 2) Assemble all chunks except two last (see above step)
+ * 3) While so, do the final check on all hashes
+ * 4) If the package is assembled back together, hash it again for
+ * the very final verification.
+ *
+ * @return void
+ */
+ public function assembleChunksFromFinalArray () {
+ // Make sure the final array is really completed
+ assert($this->ifUnassembledChunksAvailable());
+
+ // Count up stepping
+ $this->finalPackageChunks['assemble_steps']++;
+
+ // Do the next step
+ switch ($this->finalPackageChunks['assemble_steps']) {
+ case 1: // Sort the chunks array (the serial number shall act as a sorting key)
+ $this->sortChunksArray();
+ break;
+
+ case 2: // Prepare the assemble by removing last two indexes
+ $this->preparePackageAssmble();
+ break;
+
+ case 3: // Assemble all chunks back together to the original package
+ $this->assembleAllChunksToPackage();
+ break;
+
+ case 4: // Verify the raw data by hashing it again
+ $this->verifyRawPackageData();
+ break;
+
+ case 5: // Re-initialize handler to reset it to the old state
+ $this->initHandler();
+ break;
+
+ default: // Invalid step found
+ self::createDebugInstance(__CLASS__)->debugOutput('CHUNK-HANDLER[' . __LINE__ . ']: Invalid step ' . $this->finalPackageChunks['assemble_steps'] . ' detected.');
+ break;
+ } // END - switch
+ }
+
+ /**
+ * Checks whether the raw package data has been assembled back together.
+ * This can be safely assumed when rawPackageData is not empty and the
+ * collection of all chunks is FALSE (because initHandler() will reset it).
+ *
+ * @return $isRawPackageDataAvailable Whether raw package data is available
+ */
+ public function ifRawPackageDataIsAvailable () {
+ // Check it
+ $isRawPackageDataAvailable = ((!empty($this->rawPackageData)) && (!$this->ifUnassembledChunksAvailable()));
+
+ // Return it
+ return $isRawPackageDataAvailable;
+ }
+
+ /**
+ * Handles the finally assembled raw package data by feeding it into another
+ * stacker for further decoding/processing.
+ *
+ * @return void
+ */
+ public function handledAssembledRawPackageData () {
+ // Assert to make sure that there is raw package data available
+ assert($this->ifRawPackageDataIsAvailable());
+
+ // Then feed it into the next stacker
+ $this->getStackerInstance()->pushNamed(self::STACKER_NAME_ASSEMBLED_RAW_DATA, $this->rawPackageData);
+
+ // ... and reset it
+ $this->rawPackageData = '';
}
}