Example of PHP implementing RSA encryption and decryption algorithm (a method to generate a key bit number of 1024 bits)

/**
  * RSA private key encryption
  * @param string $private_key private key
  * @param string $data string to encrypt
  * @return string $encrypted Returns the encrypted string
  * @author mosishu
  */
function privateEncrypt($private_key,$data){
 $encrypted = '';
 $pi_key = openssl_pkey_get_private($private_key);//This function can be used to determine whether the private key is available, and can return the resource id Resource id //The maximum allowable encryption length is 117, and the score is encrypted in segments $plainData = str_split($data, 100);//The number of key bits generated is 1024 bit key foreach($plainData as $chunk){
  $partialEncrypted = '';
  $encryptionOk = openssl_private_encrypt($chunk,$partialEncrypted,$pi_key);//Private key encryption  if($encryptionOk === false){
   return false;
  }
  $encrypted .= $partialEncrypted;
 }
 
 $encrypted = base64_encode($encrypted);//The encrypted content usually contains special characters, and it needs to be encoded and converted. When transmitting through urls between the network, you should pay attention to whether base64 encoding is url-safe. return $encrypted;
}

/**
  * RSA public key decryption (the contents encrypted by the private key can be decrypted through the public key)
  * @param string $public_key public key
  * @param string $data string encrypted by private key
  * @return string $decrypted Returns the decrypted string
  * @author mosishu
  */
function publicDecrypt($public_key,$data){
 $decrypted = '';
 $pu_key = openssl_pkey_get_public($public_key);//This function can be used to determine whether the public key is available $plainData = str_split(base64_decode($data), 128);//The number of key bits generated is 1024 bit key foreach($plainData as $chunk){
  $str = '';
  $decryptionOk = openssl_public_decrypt($chunk,$str,$pu_key);//Public key decryption  if($decryptionOk === false){
   return false;
  }
  $decrypted .= $str;
 }
 return $decrypted;
}

//RSA public key encryptionfunction publicEncrypt($public_key,$data){
 $encrypted = '';
 $pu_key = openssl_pkey_get_public($public_key);
 $plainData = str_split($data, 100);
 foreach($plainData as $chunk){
  $partialEncrypted = '';
  $encryptionOk = openssl_public_encrypt($chunk,$partialEncrypted,$pu_key);//Public key encryption  if($encryptionOk === false){
   return false;
  }
  $encrypted .= $partialEncrypted;
 }
 $encrypted = base64_encode($encrypted);
 return $encrypted;
}

//RSA private key decryptionfunction privateDecrypt($private_key,$data){
 $decrypted = '';
 $pi_key = openssl_pkey_get_private($private_key);
 $plainData = str_split(base64_decode($data), 128); 
 foreach($plainData as $chunk){
  $str = '';
  $decryptionOk = openssl_private_decrypt($chunk,$str,$pi_key);//Decrypt the private key  if($decryptionOk === false){
   return false;
  }
  $decrypted .= $str;
 }
 return $decrypted;
}