PHP RSA加密解密实例

PHP服务端与客户端交互、提供开放api时，通常需要对敏感的部分api数据传输进行数据加密，这时候rsa非对称加密就能派上用处了，下面通过一个例子来说明如何用php来实现数据的加密解密

 

1、加密解密的第一步是生成公钥、私钥对，私钥加密的内容能通过公钥解密（反过来亦可以）

下载开源RSA密钥生成工具openssl（通常Linux系统都自带该程序），解压缩至独立的文件夹，进入其中的bin目录，执行以下命令：

openssl genrsa -out rsa_private_key.pem 1024
openssl pkcs8 -topk8 -inform PEM -in rsa_private_key.pem -outform PEM -nocrypt -out private_key.pem
openssl rsa -in rsa_private_key.pem -pubout -out rsa_public_key.pem

 

第一条命令生成原始 RSA私钥文件 rsa_private_key.pem，第二条命令将原始 RSA私钥转换为 pkcs8格式，第三条生成RSA公钥 rsa_public_key.pem
从上面看出通过私钥能生成对应的公钥，因此我们将私钥private_key.pem用在服务器端，公钥发放给Android跟iOS等前端

 

2、php中用生成的公钥、私钥进行加密解密，直接上代码

<?php  
$private_key = '-----BEGIN RSA PRIVATE KEY-----  
MIICXQIBAAKBgQC3//sR2tXw0wrC2DySx8vNGlqt3Y7ldU9+LBLI6e1KS5lfc5jl  
TGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2klBd6h4wrbbHA2XE1sq21ykja/  
Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o2n1vP1D+tD3amHsK7QIDAQAB  
AoGBAKH14bMitESqD4PYwODWmy7rrrvyFPEnJJTECLjvKB7IkrVxVDkp1XiJnGKH  
2h5syHQ5qslPSGYJ1M/XkDnGINwaLVHVD3BoKKgKg1bZn7ao5pXT+herqxaVwWs6  
ga63yVSIC8jcODxiuvxJnUMQRLaqoF6aUb/2VWc2T5MDmxLhAkEA3pwGpvXgLiWL  
3h7QLYZLrLrbFRuRN4CYl4UYaAKokkAvZly04Glle8ycgOc2DzL4eiL4l/+x/gaq  
deJU/cHLRQJBANOZY0mEoVkwhU4bScSdnfM6usQowYBEwHYYh/OTv1a3SqcCE1f+  
qbAclCqeNiHajCcDmgYJ53LfIgyv0wCS54kCQAXaPkaHclRkQlAdqUV5IWYyJ25f  
oiq+Y8SgCCs73qixrU1YpJy9yKA/meG9smsl4Oh9IOIGI+zUygh9YdSmEq0CQQC2  
4G3IP2G3lNDRdZIm5NZ7PfnmyRabxk/UgVUWdk47IwTZHFkdhxKfC8QepUhBsAHL  
QjifGXY4eJKUBm3FpDGJAkAFwUxYssiJjvrHwnHFbg0rFkvvY63OSmnRxiL4X6EY  
yI9lblCsyfpl25l7l5zmJrAHn45zAiOoBrWqpM5edu7c  
-----END RSA PRIVATE KEY-----';  
  
$public_key = '-----BEGIN PUBLIC KEY-----  
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC3//sR2tXw0wrC2DySx8vNGlqt  
3Y7ldU9+LBLI6e1KS5lfc5jlTGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2kl  
Bd6h4wrbbHA2XE1sq21ykja/Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o  
2n1vP1D+tD3amHsK7QIDAQAB  
-----END PUBLIC KEY-----';  
  
//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";  
  
  
$data = "aassssasssddd";//原始数据  
$encrypted = "";   
$decrypted = "";   
  
echo "source data:",$data,"\n";  
  
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 $encrypted,"\n";  
  
echo "public key decrypt:\n";  
  
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";  
  
echo "private key decrypt:\n";  
openssl_private_decrypt(base64_decode($encrypted),$decrypted,$pi_key);//私钥解密  
echo $decrypted,"\n";  

 

转自：http://blog.csdn.net/clh604/article/details/20224735