php rsa加密解密執行個體

1、加密解密的第一步是產生公開金鑰、私密金鑰對，私密金鑰加密的內容能通過公開金鑰解密（反過來亦可以）

下載開源RSA密鑰產生工具openssl（通常Linux系統都內建該程式），解壓縮至獨立的檔案夾，進入其中的bin目錄，執行以下命令：

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

第一條命令產生原始 RSA私密金鑰檔案 rsa_private_key.pem，第二條命令將原始 RSA私密金鑰轉換為 pkcs8格式，第三條產生RSA公開金鑰 rsa_public_key.pem
從上面看出通過私密金鑰能產生對應的公開金鑰，因此我們將私密金鑰private_key.pem用在伺服器端，公開金鑰發放給android跟ios等前端

2、php中用產生的公開金鑰、私密金鑰進行加密解密，直接上代碼

1. $private_key = '-----BEGIN RSA PRIVATE KEY-----
2. MIICXQIBAAKBgQC3//sR2tXw0wrC2DySx8vNGlqt3Y7ldU9+LBLI6e1KS5lfc5jl
3. TGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2klBd6h4wrbbHA2XE1sq21ykja/
4. Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o2n1vP1D+tD3amHsK7QIDAQAB
5. AoGBAKH14bMitESqD4PYwODWmy7rrrvyFPEnJJTECLjvKB7IkrVxVDkp1XiJnGKH
6. 2h5syHQ5qslPSGYJ1M/XkDnGINwaLVHVD3BoKKgKg1bZn7ao5pXT+herqxaVwWs6
7. ga63yVSIC8jcODxiuvxJnUMQRLaqoF6aUb/2VWc2T5MDmxLhAkEA3pwGpvXgLiWL
8. 3h7QLYZLrLrbFRuRN4CYl4UYaAKokkAvZly04Glle8ycgOc2DzL4eiL4l/+x/gaq
9. deJU/cHLRQJBANOZY0mEoVkwhU4bScSdnfM6usQowYBEwHYYh/OTv1a3SqcCE1f+
10. qbAclCqeNiHajCcDmgYJ53LfIgyv0wCS54kCQAXaPkaHclRkQlAdqUV5IWYyJ25f
11. oiq+Y8SgCCs73qixrU1YpJy9yKA/meG9smsl4Oh9IOIGI+zUygh9YdSmEq0CQQC2
12. 4G3IP2G3lNDRdZIm5NZ7PfnmyRabxk/UgVUWdk47IwTZHFkdhxKfC8QepUhBsAHL
13. QjifGXY4eJKUBm3FpDGJAkAFwUxYssiJjvrHwnHFbg0rFkvvY63OSmnRxiL4X6EY
14. yI9lblCsyfpl25l7l5zmJrAHn45zAiOoBrWqpM5edu7c
15. -----END RSA PRIVATE KEY-----';
17. $public_key = '-----BEGIN PUBLIC KEY-----
18. MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC3//sR2tXw0wrC2DySx8vNGlqt
19. 3Y7ldU9+LBLI6e1KS5lfc5jlTGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2kl
20. Bd6h4wrbbHA2XE1sq21ykja/Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o
21. 2n1vP1D+tD3amHsK7QIDAQAB
22. -----END PUBLIC KEY-----';

//echo $private_key;
$pi_key=openssl_pkey_get_private($private_key);//這個函數可用來判斷私密金鑰是否是可用的，可用返回資源id Resource id
$pu_key=openssl_pkey_get_public($public_key);//這個函數可用來判斷公開金鑰是否是可用的

print_r($pi_key);echo "\n"; echo "
";
print_r($pu_key);echo "\n"; echo "
";
echo "";

$data='php ras密碼編譯演算法';
$encrypted = "";
$decrypted = "";

echo "加密的來源資料:".$data."\n"; echo "
";
echo "private key encrypt:\n"; echo "
";
openssl_private_encrypt($data,$encrypted,$pi_key);//私密金鑰加密
$encrypted = base64_encode($encrypted);//加密後的內容通常含有特殊字元，需要編碼轉換下，在網路間通過url傳輸時要注意base64編碼是否是url安全的
echo '私密金鑰加密後：'.$encrypted."\n"; echo "
";echo "
";

echo "public key decrypt:\n"; echo "
";
openssl_public_decrypt(base64_decode($encrypted),$decrypted,$pu_key);//私密金鑰加密的內容通過公開金鑰可用解密出來
echo '公開金鑰解密後：'.$decrypted."\n"; echo "
";
echo "";

echo "public key encrypt:\n"; echo "
";
openssl_public_encrypt($data,$encrypted,$pu_key);//公開金鑰加密
$encrypted = base64_encode($encrypted);
echo $encrypted,"\n"; echo "
";

echo "private key decrypt:\n"; echo "
";
openssl_private_decrypt(base64_decode($encrypted),$decrypted,$pi_key);//私密金鑰解密
echo $decrypted,"\n"; echo "
";

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