OpenSSL PHP example for asymmetric encryption and symmetric encryption

Make sure the php OpenSSL extension is turned on: Extension=php_openssl.dll

<?php/**
* @file
* Author: Yunke url:http://blog.csdn.net/u011474028
*
*/
Header ("content-type:text/html; Charset=utf-8 ");

$key _file = "Yunkeserver.key"; Private
$publickey _file = "YUNKESERVER.CRT"; Certificate file
$publickey _file= "SERVER.CRT";//and the private key does not match the certificate file
$data _file = "Msg.txt"; Data files to be encrypted

$private _key = Openssl_get_privatekey (file_get_contents ($key _file)); Get private key non string type is resource type
echo "Private key is:<br>". $private _key. "<br><br>";
$public _key = Openssl_get_publickey (file_get_contents ($publickey _file)); Get public key non-string type is resource type
echo "Public key is:<br>." $public _key. "<br><br>";

/*
$str _key = '; String representation of key
if (Openssl_pkey_export ($private _key, $str _key)) {//The openssl.cnf file needs to be properly configured to succeed
echo "The string representation of the key is:<br>". $str _key. "<br><br>";
} else {
echo "string failure:<br> of key";
while ($msg = openssl_error_string ()) {
Echo $msg. "<br/>\n";
}
echo "<br/>";
}
*/
Print_r (Openssl_pkey_get_details ($public _key)); Output key details Here you can see that the private key contains the public key

$data = file_get_contents ($data _file);
echo "PlainText data is:<br>". $data. "<br><br>";

$crypted _data = null; Ciphertext
if (Openssl_private_encrypt ($data, $crypted _data, $private _key)) {
echo "The following is the secret key encrypted ciphertext:<br>". $crypted _data. "<br><br>";
} else {
echo "Cryptographic failure:<br>";
while ($msg = openssl_error_string ()) {
Echo $msg. "<br/>\n";
}
}
$decrypted _data = null; Encrypted plaintext after restore
if (Openssl_public_decrypt ($crypted _data, $decrypted _data, $public _key)) {
echo "Below is a clear:<br> after the public key has been decrypted." $decrypted _data. "<br><br>";
} else {
echo "Decryption failure:<br>";
while ($msg = openssl_error_string ()) {
Echo $msg. "<br/>\n";
}
}




Above for asymmetric encryption the following demonstrates symmetric encryption

$key = "123456"; Set a shared password
$cipher = ';//encryption algorithm
$arr =openssl_get_cipher_methods (); Gets the key and value of the array of supported cryptographic algorithms that do not have a corresponding relationship
$cipher = $arr [20];
echo "Selected encryption algorithm is: $cipher <br>\n";
$value =openssl_encrypt ($data, $cipher, $key); IV parameter Openssl_raw_data output RAW data
echo "Encrypted ciphertext is:<br>". $value. " <br><br> ";
$old _data=openssl_decrypt ($value, $cipher, $key);
echo "Decrypts the restored plaintext:<br>". $old _data. " <br><br> ";

Print_r ($arr);