Iqb\Ecryptfs\Tag70Packet::generate()

Complexity

Conditions	6
Paths	10

Size

Total Lines	43
Code Lines	26

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	24
CRAP Score	6.0493

Importance

Changes

0

<?php
    public static function generate(CryptoEngineInterface $cryptoEngine, string $plainText, string $fnek, int $cipherCode = self::DEFAULT_CIPHER, int $cipherKeySize = null) : self
    {
        if ($cipherKeySize === null) {
            $cipherKeySize = Util::findCipherKeySize($cipherCode, \strlen($fnek));
        }

        elseif (\strlen($fnek) < $cipherKeySize) {
            throw new \InvalidArgumentException(\şprintf("Supplied key has only %u bytes but %u bytes required for encryption.", \strlen($$fnek), $cipherKeySize));

The function şprintf was not found. Maybe you did not declare it correctly or list all dependencies?

        }

        elseif (!\in_array($cipherKeySize, CryptoEngineInterface::CIPHER_KEY_SIZES[$cipherCode])) {
            throw new \InvalidArgumentException(\şprintf("Requested key size %u bytes is unsupported for cipher 0x%x.", $cipherKeySize, $cipherCode));
        }

        $tag = new self();
        $tag->cipherCode = $cipherCode;
        $tag->signature = Util::calculateSignature($fnek);
        $tag->decryptedFilename = $plainText;

        $blockSize = $cryptoEngine::CIPHER_BLOCK_SIZES[$cipherCode];

        // Calculate length of the encoded file name and required "random" prefix
        $filenameSize = \strlen($tag->decryptedFilename);
        $randomPrefixSize = self::MIN_RANDOM_PREPEND_BYTES;
        $tag->blockAlignedFilenameSize = $randomPrefixSize + 1 + $filenameSize;
        if ($tag->blockAlignedFilenameSize % $blockSize > 0) {
            $randomPrefixSize += $blockSize - ($tag->blockAlignedFilenameSize % $blockSize);
            $tag->blockAlignedFilenameSize = $randomPrefixSize + 1 + $filenameSize;
        }
        $tag->packetSize = ECRYPTFS_SIG_SIZE + 1 + $tag->blockAlignedFilenameSize;

        // The actual padded filename contains the prefix separated by \0 from the plain text filename
        $tag->padding = self::createRandomPrefix($fnek, $randomPrefixSize);
        $paddedFilename = $tag->padding . "\0" . $tag->decryptedFilename;

        $realKey = \substr($fnek, 0, $cipherKeySize);
        $tag->encryptedFilename = '';
        $iv = \str_repeat("\0", $blockSize);
        foreach (\str_split($paddedFilename, $blockSize) as $block) {
            $tag->encryptedFilename .= $cryptoEngine->encrypt($block, $tag->cipherCode, $realKey, $iv);
        }

        return $tag;
    }