PHP RSA签名(公钥、私钥)

1、公钥、私钥格式化（加上前后戳、每64位进行换行）

/**********************************私钥格式化*************************************/

 1 function formatPriKey($priKey) {
 2     $fKey = "-----BEGIN PRIVATE KEY-----\n";
 3     $len = strlen($priKey);
 4     for($i = 0; $i < $len; ) {
 5         $fKey = $fKey . substr($priKey, $i, 64) . "\n";
 6         $i += 64;
 7     }
 8     $fKey .= "-----END PRIVATE KEY-----";
 9     return $fKey;
10 }

/**********************************公钥格式化*************************************/

 1 function formatPubKey($pubKey) {
 2     $fKey = "-----BEGIN PUBLIC KEY-----\n";
 3     $len = strlen($pubKey);
 4     for($i = 0; $i < $len; ) {
 5         $fKey = $fKey . substr($pubKey, $i, 64) . "\n";
 6         $i += 64;
 7     }
 8     $fKey .= "-----END PUBLIC KEY-----";
 9     return $fKey;
10 }

2、私钥签名、公钥验签

/**********************************私钥签名*************************************/

 1 /**
 2  * 生成签名
 3  * @param    string     $signString 待签名字符串
 4  * @param    [type]     $priKey     私钥
 5  * @return   string     base64结果值
 6  */
 7 function getSign($signString,$priKey){
 8     $privKeyId = openssl_pkey_get_private($priKey);
 9     $signature = ‘‘;
10     openssl_sign($signString, $signature, $privKeyId);
11     openssl_free_key($privKeyId);
12     return base64_encode($signature);
13 }

/**********************************公钥验签*************************************/

 1 /**
 2  * 校验签名
 3  * @param    string     $pubKey 公钥
 4  * @param    string     $sign   签名
 5  * @param    string     $toSign 待签名字符串
 6  * @param    string     $signature_alg 签名方式 比如 sha1WithRSAEncryption 或者sha512
 7  * @return   bool
 8  */
 9 function checkSign($pubKey,$sign,$toSign,$signature_alg=OPENSSL_ALGO_SHA1){
10     $publicKeyId = openssl_pkey_get_public($pubKey);
11     $result = openssl_verify($toSign, base64_decode($sign), $publicKeyId,$signature_alg);
12     openssl_free_key($publicKeyId);
13     return $result === 1 ? true : false;
14 }

3、公钥加密、私钥解密

/**********************************公钥加密*************************************/

 1 /**
 2  *公钥加密
 3   *@param    string     $sign_str   待加密字符串
 4   *@param    string     $public_key  公钥
 5   *@param    string     $signature_alg 加密方式
 6   *@return    string
 7 */
 8  function get_public_sign($sign_str,$public_key,$signature_alg=OPENSSL_ALGO_SHA1){
 9      $public_key = openssl_pkey_get_public($public_key);//加载密钥
10      openssl_sign($sign_str,$signature,$public_key,$signature_alg);//生成签名
11     $signature = base64_encode($signature);
12     openssl_free_key($public);
13     return $signature;
14  }

/**********************************私钥解密**************************************/

 1  /**
 2   *私钥解密
 3   *@param    string     $sign_str   待加密字符串
 4   *@param    string     $sign sign
 5   *@param    string     $private_key 私钥
 6   *@param    string     $signature_alg 加密方式
 7   *@return     bool
 8 */
 9
10  function private_verify($sign_str,$sign,$private_key,$signature_alg=OPENSSL_ALGO_SHA1){
11     $private_key = openssl_get_privatekey($private_key);
12     $verify = openssl_verify($sign_str, base64_decode($sign), $private_key, $signature_alg);
13     openssl_free_key($private_key);
14     return $verify==1;//false or true
15 }

示例代码如下（私钥签名公钥验签）：

<?php

$pubKey = ‘-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDr6H/ictALLsV9/63lPFSYDPQK
gRwEM2FiewfR/BYaPGfpgdl8lelNYqFxnqBRKbGnbFOwOxOu7oiiPYaJxcSU94hI
d3S0/UsSXyRfTaHT8ZZv+5luikQAG62hwkxqcSdL3aEMbqsHRfQ9RXiFAneiJJwZ
1D0nHPANfBA4UN+OXQIDAQAB
-----END PUBLIC KEY-----‘;

$priKey = ‘-----BEGIN PRIVATE KEY-----
MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBAOvof+Jy0AsuxX3/
reU8VJgM9AqBHAQzYWJ7B9H8Fho8Z+mB2XyV6U1ioXGeoFEpsadsU7A7E67uiKI9
honFxJT3iEh3dLT9SxJfJF9NodPxlm/7mW6KRAAbraHCTGpxJ0vdoQxuqwdF9D1F
eIUCd6IknBnUPScc8A18EDhQ345dAgMBAAECgYEAoNlVIQShn45TcBa97dhV4Zqr
ZuIjRSX3V5uFeIKGW3smastzjAP3ICGI7Jx4uP5RuFMfOMD/Kb5QgTasHhIvdwe0
kuMdUqd8YCLgZaV1u02GWkp5I7bG2HRKAqfrpaExeOJt3Iqmggt208P3BNQLTOa2
NFtNqT+onI1dGwbC120CQQD2BbkrXPv+wGAKkcqIK77Bkrwpg7Iqj91uyVHBAleW
AgfWDFA3rJb8jDCARHte2ehMImmhbsQmVBjdI1DNdYWLAkEA9XnEoVVIL5IA09s0
XtL/Na065loDTJsQZiumdi6VMn6zWafu6GFhS0w5DQdkjtA7qhwpftjVRaWtK0DX
4qpItwJAKxGrbfT0RI/HAHKvYxFNbrPSbu4YNa1D1Y422rQfQyqN1qIHNQfo0sN0
BjB27I73RMTNey5Z9l/IjoYNMjq9qwJABChZ0jm1jUi1xuDRlEGSnQAgHUKtB6Eg
t/pJSXskf8RxmTUk8L6lfTb/SF81rs2MFSeA9GsLwbA6rJ7eiTJFJQJBAJnixcdp
F6knRxyOUDhWoa8uYmnUdcyrfo4dnNyliJbNTTSw0LJAGZsCbo9EDqQIxDrqDa9X
qj0yz6UT1JM37Tk=
-----END PRIVATE KEY-----‘;

//$priKey = formatPriKey($priKey);
//$pubKey = formatPubKey($pubKey);
$params = [
    "merchant_id"=>"1",
    "uid"=>"2122334455",
    "out_trade_id"=>"13423423423",
    "amount"=>"88",
    "subject"=>"活动红包"
];

//获取预处理字符串
$signString = getSignString($params);
//预处理字符串为
//amount=88&merchant_id=1&out_trade_id=13423423423&subject=活动红包&uid=2122334455

//获取签名
$sign = getSign($signString,$priKey);

//生成的签名为
//k8DMuhe+q9rDVDgzAk8lFQEE+tZAahXLiZWExmiYl83vJpZlnKTBghLd1DM8itNzw3JYGhxR8ueHCIkkGyVh0BiPuKYmXFyrCwLVif9sMWCu2DFoEDFARZClDRCfE5rV+IDmumCBfVyxFY/uW/DIMS7AO7GlrydW5aVZ6xYKtBw=

//验证签名
$res = checkSign($pubKey,$sign,$signString);
var_dump($res);//结果为 true

/**
 * 生成签名
 * @param    string     $signString 待签名字符串
 * @param    [type]     $priKey     私钥
 * @return   string     base64结果值
 */
function getSign($signString,$priKey){
    $privKeyId = openssl_pkey_get_private($priKey);
    $signature = ‘‘;
    openssl_sign($signString, $signature, $privKeyId);
    openssl_free_key($privKeyId);
    return base64_encode($signature);
}

/**
 * 校验签名
 * @param    string     $pubKey 公钥
 * @param    string     $sign   签名
 * @param    string     $toSign 待签名字符串
 * @param    string     $signature_alg 签名方式 比如 sha1WithRSAEncryption 或者sha512
 * @return   bool
 */
function checkSign($pubKey,$sign,$toSign,$signature_alg=OPENSSL_ALGO_SHA1){
    $publicKeyId = openssl_pkey_get_public($pubKey);
    $result = openssl_verify($toSign, base64_decode($sign), $publicKeyId,$signature_alg);
    openssl_free_key($publicKeyId);
    return $result === 1 ? true : false;
}

/**
 * 获取待签名字符串
 * @param    array     $params 参数数组
 * @return   string
 */
function getSignString($params){
    unset($params[‘sign‘]);
    ksort($params);
    reset($params);

    $pairs = array();
    foreach ($params as $k => $v) {
        if(!empty($v)){
            $pairs[] = "$k=$v";
        }
    }

    return implode(‘&‘, $pairs);
}

/**
 * 格式化私钥
 */
function formatPriKey($priKey) {
    $fKey = "-----BEGIN PRIVATE KEY-----\n";
    $len = strlen($priKey);
    for($i = 0; $i < $len; ) {
        $fKey = $fKey . substr($priKey, $i, 64) . "\n";
        $i += 64;
    }
    $fKey .= "-----END PRIVATE KEY-----";
    return $fKey;
}

/**
 * 格式化公钥
 */
function formatPubKey($pubKey) {
    $fKey = "-----BEGIN PUBLIC KEY-----\n";
    $len = strlen($pubKey);
    for($i = 0; $i < $len; ) {
        $fKey = $fKey . substr($pubKey, $i, 64) . "\n";
        $i += 64;
    }
    $fKey .= "-----END PUBLIC KEY-----";
    return $fKey;
}
?>

原文地址：https://www.cnblogs.com/changning0822/p/9964258.html