首先,关于RSA的加密介绍文章,就不多说了。直接看这个网页吧(作者写的计算机科普文章是极好的)
http://www.ruanyifeng.com/blog/2013/06/rsa_algorithm_part_one.html
我要实现的功能就是通过这对公钥和密钥,实现客户端软件对密码进行加密(采用公钥),然后网站端(php)采用密钥进行解密验证。
开始吧。
php服务端利用内置函数生成公钥和密钥。记得这需要php服务器安装了openssl扩展。先生成cer文件和pfx文件。cer文件相当于公钥(可以发给客户端),pfx是密钥(必须严格保存于服务器端不能泄露)。
$dn = array( "countryName" => 'zh', //所在国家名称 "stateOrProvinceName" => 'GuangDong', //所在省份名称 "localityName" => 'ShenZhen', //所在城市名称 "organizationName" => 'baibai', //注册人姓名 "organizationalUnitName" => 'company', //组织名称 "commonName" => 'bbb', //公共名称 "emailAddress" => '123@.qq.com' //邮箱 ); $privkeypass = 'cf'; //私钥密码 $numberofdays = 3650; //有效时长 $cerpath = "./test.cer"; //生成证书路径 $pfxpath = "./test.pfx"; //密钥文件路径//生成证书 $privkey = openssl_pkey_new(); $csr = openssl_csr_new($dn, $privkey); $sscert = openssl_csr_sign($csr, null, $privkey, $numberofdays); openssl_x509_export_to_file($sscert, $cerpath); //导出证书到文件 //openssl_pkcs12_export_to_file($sscert, $pfxpath, $privkey, $privkeypass); //生成密钥文件 openssl_pkey_export_to_file($privkey, $pfxpath); //生成密钥文件
以下是是php端进行简单测试的代码:
/*
//私钥加密
$cer_key = file_get_contents($pfxpath); //获取密钥内容
openssl_pkcs12_read($cer_key, $certs, $privkeypass);
openssl_sign($data, $signMsg, $certs['pkey'],OPENSSL_ALGO_SHA1); //注册生成加密信息
$signMsg = base64_encode($signMsg); //base64转码加密信息
//echo $signMsg;
//公钥解密
$cer_key = file_get_contents($cerpath); //获取证书内容
$unsignMsg=base64_decode($signMsg);//base64解码加密信息
$cer = openssl_x509_read($cer_key); //读取公钥
$res = openssl_verify($data, $unsignMsg, $cer); //验证
echo $res; //输出验证结果,1:验证成功,0:验证失败
*/
$data = "123456";
$crypted = "";
$key = file_get_contents($cerpath);
//公钥加密
openssl_public_encrypt($data, $crypted, $key);
echo base64_encode($crypted)."<br>";
//echo $crypted."<br>";
//私钥解密
$decrypted = "";
$s = file_get_contents($pfxpath);
//echo "<br>$s<br>";
$key2 = openssl_pkey_get_private(file_get_contents($pfxpath));
if(openssl_private_decrypt($crypted, $decrypted, $key2)){
echo $decrypted;
}
else{
echo "failed";
}
客户端通过加载cer文件,将要加密的文本用公钥加密。以下是一个函数
//通过读取本地的cer文件,得到公钥,然后对文本内容加密,返回加密后的文本,最后传到服务器端,与密钥进行比对
public static String getRSAText(Context context,String strText){
try {
//读取证书文件
InputStream inStream = context.getResources().getAssets().open("test.cer");
//创建X509工厂类
CertificateFactory cf = CertificateFactory.getInstance("X.509");
//创建证书对象
X509Certificate cert = (X509Certificate)cf.generateCertificate(inStream);
inStream.close();
Cipher c1 = Cipher.getInstance("RSA/None/PKCS1Padding");
c1.init(Cipher.PUBLIC_KEY, cert);
byte[] cipherText = c1.doFinal(strText.getBytes());
//base64转换一下,方便传输
String res = Base64.encodeToString(cipherText,Base64.DEFAULT);
return res;
}
catch (InvalidKeyException e){
}
catch (IOException e){
}
catch (CertificateException e){
}
catch (NoSuchPaddingException e){
}
catch (IllegalBlockSizeException e){
}
catch (BadPaddingException e){
}
catch (NoSuchAlgorithmException e){
}
return "";
}
下边是php端用pfx文件(里边放有密钥)进行解密的代码。我改写成了一个函数。参数是pfx文件路径,pfx文件名,要解密的字符串
function getPassword( $path,$pfx_file_name,$str ){
$pfxpath = $path . "/public/$pfx_file_name"; //密钥文件路径
//$cerpath = "./test.cer"; //生成证书路径
//私钥解密
$decrypted = "";
$key2 = openssl_pkey_get_private(file_get_contents($pfxpath));
$res = openssl_private_decrypt(base64_decode($str), $decrypted, $key2);
if($res){
return $decrypted;
}
else{
return "";
}
}