PHP RSA encryption and decryption example

Reprinted from: http://orangeholic.iteye.com/blog/2161771
Reference: http://blog.csdn.net/clh604/article/details/20224735
1. Generate key and public key
You need to prepare the openssl environment before starting
Linux needs to install openssl tool package, portal
http://www.openssl.org/source/
You need to install openssl program under window, portal
http://slproweb.com/products/Win32OpenSSL.html
If you don't want to install it, you can use the key and public key provided in this example for testing.

Key generation
openssl genrsa is used to generate rsa private key files. The private key length and password protection can be specified during generation. Please refer to the documentation for specific parameters.

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
The first command generates the original RSA private key file rsa_private_key.pem. The second command converts the original RSA private key to pkcs8 format and outputs the private key with the file name private_key.pem. The third command generates the corresponding RSA based on the private key. Public key rsa_public_key.pem
It can be seen from the above that the corresponding public key can be generated through the private key, so we use the private key private_key.pem on the server side, and the public key is issued to front-ends such as android and ios, and vice versa. When copying, only copy the openssl backend. content.

2.PHP uses RSA encryption and decryption
Before starting, you need to prepare the php openssl environment, enable the PHP openssl extension, and change the
in the php configuration file php.ini in the window. ;extension=php_openssl.dll
Change to
extension=php_openssl.dll

The code is as follows:

<code><span><span><?php</span><span>$private_key</span> = <span>'-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----'</span>;

<span>$public_key</span> = <span>'-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC3//sR2tXw0wrC2DySx8vNGlqt
3Y7ldU9+LBLI6e1KS5lfc5jlTGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2kl
Bd6h4wrbbHA2XE1sq21ykja/Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o
2n1vP1D+tD3amHsK7QIDAQAB
-----END PUBLIC KEY-----'</span>;

<span>//echo $private_key;</span><span>$pi_key</span> =  openssl_pkey_get_private(<span>$private_key</span>);<span>//这个函数可用来判断私钥是否是可用的，可用返回资源id Resource id</span><span>$pu_key</span> = openssl_pkey_get_public(<span>$public_key</span>);<span>//这个函数可用来判断公钥是否是可用的</span>
print_r(<span>$pi_key</span>);<span>echo</span><span>"\n"</span>;
print_r(<span>$pu_key</span>);<span>echo</span><span>"\n"</span>;


<span>$data</span> = <span>"aassssasssddd"</span>;<span>//原始数据</span><span>$encrypted</span> = <span>""</span>; 
<span>$decrypted</span> = <span>""</span>; 

<span>echo</span><span>"source data:"</span>,<span>$data</span>,<span>"\n"</span>;

<span>echo</span><span>"private key encrypt:\n"</span>;

openssl_private_encrypt(<span>$data</span>,<span>$encrypted</span>,<span>$pi_key</span>);<span>//私钥加密</span><span>$encrypted</span> = base64_encode(<span>$encrypted</span>);<span>//加密后的内容通常含有特殊字符，需要编码转换下，在网络间通过url传输时要注意base64编码是否是url安全的</span><span>echo</span><span>$encrypted</span>,<span>"\n"</span>;

<span>echo</span><span>"public key decrypt:\n"</span>;

openssl_public_decrypt(base64_decode(<span>$encrypted</span>),<span>$decrypted</span>,<span>$pu_key</span>);<span>//私钥加密的内容通过公钥可用解密出来</span><span>echo</span><span>$decrypted</span>,<span>"\n"</span>;

<span>echo</span><span>"---------------------------------------\n"</span>;
<span>echo</span><span>"public key encrypt:\n"</span>;

openssl_public_encrypt(<span>$data</span>,<span>$encrypted</span>,<span>$pu_key</span>);<span>//公钥加密</span><span>$encrypted</span> = base64_encode(<span>$encrypted</span>);
<span>echo</span><span>$encrypted</span>,<span>"\n"</span>;

<span>echo</span><span>"private key decrypt:\n"</span>;
openssl_private_decrypt(base64_decode(<span>$encrypted</span>),<span>$decrypted</span>,<span>$pi_key</span>);<span>//私钥解密</span><span>echo</span><span>$decrypted</span>,<span>"\n"</span>;</span></code>

Result:

<code>原数据为<span>:</span>我的帐号是<span>:shiki</span>,密码是<span>:matata</span>
加密成功，加密后数据(base64_encode后)为<span>:X6q/u/hUW4o7z0tETaWuRt3ahvgT9/m+yiqABDDs9ccHRekB0YU9UAv5zA/VZawLoDVhiyl9bAc3WHeRIexz+gybUJKkI69RFkWHL5n3llfCeTdnSXIQ4Aa+ysfmCicxXwMeP2vUWZBcxJiRVLiGGe1shJjw/TxvmocOlaFRVnQ=</span>
解密成功，解密后数据为<span>:</span>我的帐号是<span>:shiki</span>,密码是<span>:matata</span></code>

The above introduces the PHP RSA encryption and decryption example, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.