(PHP 4 >= 4.0.2, PHP 5, PHP 7)
mcrypt_encrypt — Encrypts plaintext with given parameters
$cipher
, string $key
, string $data
, string $mode
[, string $iv
] )Encrypts the data and returns it.
cipherEine der Konstanten von MCRYPT_ciphername oder der Name eines Algorithmus als Zeichenkette.
key
The key with which the data will be encrypted. If the provided key size is
not supported by the cipher, the function will emit a warning and return FALSE
data
The data that will be encrypted with the given cipher
and mode. If the size of the data is not n * blocksize,
the data will be padded with '\0'.
The returned crypttext can be larger than the size of the data that was
given by data.
modeEine der Konstanten von MCRYPT_MODE_modename oder eine der folgenden Zeichenketten: "ecb", "cbc", "cfb", "ofb", "nofb" oder "stream".
ivWird für die Initialisierung in den Modi CBC, CFB oder OFB und von einigen Algorithmen im STREAM-Modus verwendet. Wird die Länge des angegebenen IV vom betriebsmodus nicht unterstützt, oder wurde kein IV angegeben aber der Betriebsmodus benötigt einen, so wird diese Funktion eine Warnung ausgeben und FALSE zurückgeben.
Returns the encrypted data as a string Im Fehlerfall wird FALSE zurückgegeben..
| Version | Beschreibung |
|---|---|
| 5.6.0 |
Invalid key and iv sizes
are no longer accepted. mcrypt_encrypt() will now throw
a warning and return FALSE if the inputs are invalid. Previously keys and
IVs were padded with '\0' bytes to the next valid size.
|
Beispiel #1 mcrypt_encrypt() Example
<?php
# --- ENCRYPTION ---
# the key should be random binary, use scrypt, bcrypt or PBKDF2 to
# convert a string into a key
# key is specified using hexadecimal
$key = pack('H*', "bcb04b7e103a0cd8b54763051cef08bc55abe029fdebae5e1d417e2ffb2a00a3");
# show key size use either 16, 24 or 32 byte keys for AES-128, 192
# and 256 respectively
$key_size = strlen($key);
echo "Key size: " . $key_size . "\n";
$plaintext = "This string was AES-256 / CBC / ZeroBytePadding encrypted.";
# create a random IV to use with CBC encoding
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
# creates a cipher text compatible with AES (Rijndael block size = 128)
# to keep the text confidential
# only suitable for encoded input that never ends with value 00h
# (because of default zero padding)
$ciphertext = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key,
$plaintext, MCRYPT_MODE_CBC, $iv);
# prepend the IV for it to be available for decryption
$ciphertext = $iv . $ciphertext;
# encode the resulting cipher text so it can be represented by a string
$ciphertext_base64 = base64_encode($ciphertext);
echo $ciphertext_base64 . "\n";
# === WARNING ===
# Resulting cipher text has no integrity or authenticity added
# and is not protected against padding oracle attacks.
# --- DECRYPTION ---
$ciphertext_dec = base64_decode($ciphertext_base64);
# retrieves the IV, iv_size should be created using mcrypt_get_iv_size()
$iv_dec = substr($ciphertext_dec, 0, $iv_size);
# retrieves the cipher text (everything except the $iv_size in the front)
$ciphertext_dec = substr($ciphertext_dec, $iv_size);
# may remove 00h valued characters from end of plain text
$plaintext_dec = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key,
$ciphertext_dec, MCRYPT_MODE_CBC, $iv_dec);
echo $plaintext_dec . "\n";
?>
Das oben gezeigte Beispiel erzeugt folgende Ausgabe:
Key size: 32 ENJW8mS2KaJoNB5E5CoSAAu0xARgsR1bdzFWpEn+poYw45q+73az5kYi4j+0haevext1dGrcW8Qi59txfCBV8BBj3bzRP3dFCp3CPQSJ8eU= This string was AES-256 / CBC / ZeroBytePadding encrypted.