怎么在php中使用openssl实现一个rsa加密解密功能

，具体如下：

<?php
$config = array(
//"config" =>"D:/phpserver/Lighttpd/openssl.cnf",
//'config' =>'D:/phpStudy/Lighttpd/OpenSSL.cnf',
'private_key_bits' => 1024,  // Size of Key.
'private_key_type' => OPENSSL_KEYTYPE_RSA
);
//$res = openssl_pkey_new();
$res = openssl_pkey_new($config);
// Get private key
// openssl_pkey_export($res, $privkey, "PassPhrase number 1" );
openssl_pkey_export($res, $privkey);
var_dump($privkey);
// Get public key
$pubkey=openssl_pkey_get_details($res);
// echo "------------><br />";
// print_r($pubkey["rsa"]);
// $bin_str=$pubkey["rsa"]["n"];
// print_r($bin_str);
// echo "<br />";
// //echo $bin_hex_str = pack("H*" , bin2hex($bin_str));
// echo $bin_hex_str = bin2hex($bin_str);
// echo "<br />------------<<br />";
 $pubkey=$pubkey["key"];
// var_dump($privkey);
// var_dump($pubkey);
echo $privkey."<br /><br />";
echo $pubkey."<br /><br />";
?>

<?php
$private_key = '-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----';
//$private_key ='-----BEGIN RSA PRIVATE KEY-----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//-----END RSA PRIVATE KEY-----';
$public_key = '-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDNSQ4AmPZE01MpEO9dabRDsS0X
wxKekEFUoWJneFG+NA6P52JsISw79QYNfQwM7akIaPpzU0+kkWjTSXiDqFUv5y2v
aA3W2Tre5N51uCwUK6/LfzHXBg0d+Bnlzy6Kb6bpgPgvbhAkNbvjbCS0V9h5v3WU
TLR9QauJ05Q8qe70sQIDAQAB
-----END PUBLIC KEY-----';
//$private_key=$privkey;
//$public_key=$pubkey;
$fp=fopen("private_key","w");
fwrite($fp,$private_key);
fclose($fp);
$fp=fopen("public_key","w");
fwrite($fp,$public_key);
fclose($fp);
//echo $private_key;
$pi_key = openssl_pkey_get_private($private_key);//这个函数可用来判断私钥是否是可用的，可用返回资源id Resource id
$pu_key = openssl_pkey_get_public($public_key);//这个函数可用来判断公钥是否是可用的
print_r($pi_key);echo "\n";
print_r($pu_key);echo "\n";
echo "<br />----------------------<br />";
$data = "woshizhu";//原始数据
$encrypted = ""; 
$decrypted = "";
echo "source data:",$data,"<br />";
echo "private key encrypt:\n";
openssl_private_encrypt($data,$encrypted,$pi_key);//私钥加密
$encrypted = base64_encode($encrypted);//加密后的内容通常含有特殊字符，需要编码转换下，在网络间通过url传输时要注意base64编码是否是url安全的
echo "<br />----------私钥加密------------<br />";
echo $encrypted,"<br />";
echo "<br />----------私钥加密------------<br />";
echo "public key decrypt:\n";
$decrypted="";
openssl_public_decrypt(base64_decode($encrypted),$decrypted,$pu_key);//私钥加密的内容通过公钥可用解密出来
echo $decrypted,"\n";
echo "---------------------------------------\n";
echo "public key encrypt:\n";
openssl_public_encrypt($data,$encrypted,$pu_key);//公钥加密
$encrypted = base64_encode($encrypted);
echo $encrypted,"\n";
$decrypted="";
//$encrypted="JBeapcp9iWWYJYElgqtrZxfxM4wVkCaSn/oJZ7NjfR23o76fdbxEXpf+PGWACw3PeTdObwL4108wR3ihKmy2iYkIExGjBYyvx2w9aHies8ZsOIP3LjiMHYTm93Rr8Sc5XxHWQc3Dhbq16JWHYZ2d+RrOpHd4x84GF3JXwivrGO4=";
echo "private key decrypt:\n";
openssl_private_decrypt(base64_decode($encrypted),$decrypted,$pi_key);//私钥解密
echo "--->:".$decrypted,"\n";
?>