Bug #73812 [Nab]: openssl_error_string() dubious when decrypting aes-128-ccm

Edit report at https://bugs.php.net/bug.php?id=73812&edit=1 ID: 73812 Updated by: bukka@php.net Reported by: anthon dot pang at gmail dot com Summary: openssl_error_string() dubious when decrypting aes-128-ccm Status: Not a bug Type: Bug Package: OpenSSL related PHP Version: 7.1.0 Assigned To: bukka Block user comment: N Private report: N New Comment: Actually missed that you pass digest. In that case it means that $digest needs to be 16 bytes (strlen($digest) === 16)... ;) Previous Comments: ------------------------------------------------------------------------ [2017-01-15 21:16:30] bukka@php.net I mean that in your example $password needs to by 16 bytes (128 bits as it's the block size of aes-128) ------------------------------------------------------------------------ [2017-01-09 20:12:39] anthon dot pang at gmail dot com In the context of my example, do you mean $password or $digest needs to match the block length? ------------------------------------------------------------------------ [2017-01-09 18:53:16] bukka@php.net Yeah this is expected. It is due to fact that you supplied password that doesn't match the exact block length so it's either filled with 0 bytes (if short) or trimmed (if long). This behaviour cannot be changed due to BC concern. ------------------------------------------------------------------------ [2016-12-25 19:04:16] anthon dot pang at gmail dot com Description: ------------ openssl_error_string() returns a dubious message, "error:0607A082:digital envelope routines:EVP_CIPHER_CTX_set_key_length:invalid key length" when decrypting even though the payload was successfully decrypted (In the test script, the payload was produced using sjcl.) Test script: --------------- <?php $password = 'password'; $input = json_decode('{"iv":"A0DOQPxWAlJ5LHjoyg==","v":1,"iter":1000,"ks":128,"ts":64,"mode":"ccm","adata":"","cipher":"aes","salt":"Kk+ws1Xj0Xo=","ct":"NCPpLCHLLO5mBOGpSUpHdXPgKZA="}', true); $digest = hash_pbkdf2('sha256', $password, base64_decode($input['salt']), $input['iter'], 0, true); $cipher = $input['cipher'] . '-' . $input['ks'] . '-' . $input['mode']; $ct = substr(base64_decode($input['ct']), 0, - $input['ts'] / 8); $tag = substr(base64_decode($input['ct']), - $input['ts'] / 8); $iv = base64_decode($input['iv']); $adata = $input['adata']; $dt = openssl_decrypt($ct, $cipher, $digest, OPENSSL_RAW_DATA, $iv, $tag, $adata); var_dump($dt); while ($msg = openssl_error_string()) { echo $msg . "\n"; } Expected result: ---------------- string(12) "Hello World!" Actual result: -------------- string(12) "Hello World!" error:0607A082:digital envelope routines:EVP_CIPHER_CTX_set_key_length:invalid key length ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=73812&edit=1