fix: check $pos before decode

closed: #13

Author: Rhilip

src/Bencode.php

@@ -56,7 +56,11 @@ public static function decode($data, &$pos = 0)
     {
         $start_decode = ($pos === 0);   // If it is the root call ?
         if ($start_decode && (!is_string($data) || strlen($data) == 0)) {
-            throw new ParseException('Decode Input is not valid String.');
+            throw new ParseException('Decode Input is not valid String');
+        }
+
+        if ($pos >= strlen($data)) {
+            throw new ParseException('Unterminated bencode string literal');
         }
 
         if ($data[$pos] === 'd') {
@@ -69,7 +73,7 @@ public static function decode($data, &$pos = 0)
                     break;
                 }
                 if (!is_string($key)) {
-                    throw new ParseException('Non string key found in the dictionary.');
+                    throw new ParseException('Non string key found in the dictionary');
                 } elseif (array_key_exists($key, $return)) {
                     throw new ParseException('Duplicate Dictionary key exist before: ' . $key);
                 }

src/TorrentFile.php

@@ -53,7 +53,7 @@ class TorrentFile
     protected static function checkTorrentDict($dict, $key, $type = null)
     {
         if (!is_array($dict)) {
-            throw new ParseException('Checking non-dictionary value.');
+            throw new ParseException('Checking non-dictionary value');
         }
 
         if (!isset($dict[$key])) {
@@ -578,7 +578,7 @@ public function parse()
             if ($this->getProtocol() === self::PROTOCOL_V1) {  // Do what we do in protocol v1
                 $pieces = self::checkTorrentDict($info, 'pieces', 'string');
                 if (strlen($pieces) % 20 != 0) {
-                    throw new ParseException('Invalid pieces length.');
+                    throw new ParseException('Invalid pieces length');
                 }
 
                 if ($this->getFileMode() === self::FILEMODE_SINGLE) {
@@ -596,7 +596,7 @@ public function parse()
 
                         foreach ($paths as $path) {
                             if (!is_string($path)) {
-                                throw new ParseException('Invalid path with non-string value.');
+                                throw new ParseException('Invalid path with non-string value');
                             }
                         }
 
@@ -635,15 +635,14 @@ public function parse()
                         $length = self::checkTorrentDict($file, 'length', 'integer');
                         if ($length > $pieceLength) {  // check pieces root of large file is exist in $root['picec layers'] or not
                             if (!array_key_exists($piecesRoot, $pieceLayers)) {
-                                throw new ParseException('Pieces not exist in piece layers.');
+                                throw new ParseException('Pieces not exist in piece layers');
                             }
                         }
 
                         $addFile($paths, $length);
                         $merkleTree = $length;  // rewrite merkleTree to size, it's safe since it not affect $data['info']['file tree']
                     } else {
                         $parent_path = $paths;  // store parent paths
-                        /** @noinspection PhpParameterByRefIsNotUsedAsReferenceInspection */
                         foreach ($merkleTree as $k => &$v) {  // Loop tree
                             $paths[] = $k;   // push current path into paths
                             $loopMerkleTree($v, $paths);  // Loop check

tests/DecodeTest.php

@@ -218,7 +218,7 @@ public function testDecodeDictionarySorted()
     public function testDecodeDictionaryKeyNotString()
     {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Non string key found in the dictionary.');
+        $this->expectExceptionMessage('Non string key found in the dictionary');
 
         Bencode::decode('di123ei321ee');
     }
@@ -263,7 +263,7 @@ public function testDecodeTorrent()
     public function testDecodeNothing()
     {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Decode Input is not valid String.');
+        $this->expectExceptionMessage('Decode Input is not valid String');
 
         Bencode::decode('');
     }
@@ -274,7 +274,7 @@ public function testDecodeNothing()
     public function testDecodeNull()
     {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Decode Input is not valid String.');
+        $this->expectExceptionMessage('Decode Input is not valid String');
 
         Bencode::decode(null);
     }

tests/TorrentV1MultiTest.php

@@ -60,7 +60,7 @@ public function testFilesPathNotArray() {
 
     public function testFilesPathEntityNotString() {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Invalid path with non-string value.');
+        $this->expectExceptionMessage('Invalid path with non-string value');
 
         $files = $this->torrent->getInfoField('files');
         $files[0]['path'][0] = 123;

tests/traits/TorrentFileV1Trait.php

@@ -10,9 +10,9 @@ trait TorrentFileV1Trait
 
     public function testV1WithWrongPieces() {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Invalid pieces length.');
+        $this->expectExceptionMessage('Invalid pieces length');
 
         $this->torrent->setInfoField('pieces', $this->torrent->getRootField('pieces') . 'somestring');
         $this->torrent->parse();
     }
-}
+}

tests/traits/TorrentFileV2Trait.php

@@ -60,12 +60,12 @@ public function testInvalidNodeLength() {
 
     public function testNodePiecesRootNotExistInPieceLayer() {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('Pieces not exist in piece layers.');
+        $this->expectExceptionMessage('Pieces not exist in piece layers');
 
         $fileTree = $this->torrent->getInfoField('file tree');
         $fileTree['file1.dat']['']['pieces root'] = hash('sha256', 'adfadsfasd',true);
 
         $this->torrent->setInfoField('file tree', $fileTree);
         $this->torrent->parse();
     }
-}
+}