openssl_sign

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

openssl_sign — 生成签名

说明

function openssl_sign(
    string $data,
    string &$signature,
    #[\SensitiveParameter]OpenSSLAsymmetricKey|OpenSSLCertificate|array|string $private_key,
    string|int $algorithm = OPENSSL_ALGO_SHA1,
    int $padding = 0
): bool

openssl_sign() 使用与 private_key 关联的私钥为指定的 data 生成加密数字签名。注意数据本身并未被加密。

参数

data

要签名的数据字符串。

signature

如果调用成功，签名将返回到 signature 中。

private_key

OpenSSLAsymmetricKey - 一个密钥，通过 openssl_get_privatekey() 函数返回。

string - 一个 PEM 格式的密钥。

algorithm

int - 以下签名算法之一。

string - 由 openssl_get_md_methods() 函数返回的有效字符串，例如 "sha256WithRSAEncryption" 或 "sha384"。

padding

RSA PSS 填充方案。

返回值

成功时返回 true，或者在失败时返回 false。

更新日志

版本	说明
8.5.0	添加了可选参数 `padding`。
8.0.0	`private_key` 现在接受 OpenSSLAsymmetricKey 或 OpenSSLCertificate 实例；之前接受类型 `OpenSSL key` 或 `OpenSSL X.509` 的 resource。

示例

示例 #1 openssl_sign() 示例

<?php
// $data is assumed to contain the data to be signed

// fetch private key from file and ready it
$pkeyid = openssl_pkey_get_private("file://src/openssl-0.9.6/demos/sign/key.pem");

// compute signature
openssl_sign($data, $signature, $pkeyid);

// free the key from memory
openssl_free_key($pkeyid);
?>

示例 #2 openssl_sign() 示例

<?php
//data you want to sign
$data = 'my data';

//create new private and public key
$new_key_pair = openssl_pkey_new(array(
    "private_key_bits" => 2048,
    "private_key_type" => OPENSSL_KEYTYPE_RSA,
));
openssl_pkey_export($new_key_pair, $private_key_pem);

$details = openssl_pkey_get_details($new_key_pair);
$public_key_pem = $details['key'];

//create signature
openssl_sign($data, $signature, $private_key_pem, OPENSSL_ALGO_SHA256);

//save for later
file_put_contents('private_key.pem', $private_key_pem);
file_put_contents('public_key.pem', $public_key_pem);
file_put_contents('signature.dat', $signature);

//verify signature
$r = openssl_verify($data, $signature, $public_key_pem, "sha256WithRSAEncryption");
var_dump($r);
?>

参见

openssl_verify() - 验证签名

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＋添加备注

用户贡献的备注 3 notes

down

edmarw at yahoo dot com ¶

18 years ago

This may help if you just want a real-simple private/public key pair:

<?php

$data = "Beeeeer is really good.. hic...";

// You can get a simple private/public key pair using:
// openssl genrsa 512 >private_key.txt
// openssl rsa -pubout <private_key.txt >public_key.txt

// IMPORTANT: The key pair below is provided for testing only. 
// For security reasons you must get a new key pair
// for production use, obviously.

$private_key = <<<EOD
-----BEGIN RSA PRIVATE KEY-----
MIIBOgIBAAJBANDiE2+Xi/WnO+s120NiiJhNyIButVu6zxqlVzz0wy2j4kQVUC4Z
RZD80IY+4wIiX2YxKBZKGnd2TtPkcJ/ljkUCAwEAAQJAL151ZeMKHEU2c1qdRKS9
sTxCcc2pVwoAGVzRccNX16tfmCf8FjxuM3WmLdsPxYoHrwb1LFNxiNk1MXrxjH3R
6QIhAPB7edmcjH4bhMaJBztcbNE1VRCEi/bisAwiPPMq9/2nAiEA3lyc5+f6DEIJ
h1y6BWkdVULDSM+jpi1XiV/DevxuijMCIQCAEPGqHsF+4v7Jj+3HAgh9PU6otj2n
Y79nJtCYmvhoHwIgNDePaS4inApN7omp7WdXyhPZhBmulnGDYvEoGJN66d0CIHra
I2SvDkQ5CmrzkW5qPaE2oO7BSqAhRZxiYpZFb5CI
-----END RSA PRIVATE KEY-----
EOD;
$public_key = <<<EOD
-----BEGIN PUBLIC KEY-----
MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANDiE2+Xi/WnO+s120NiiJhNyIButVu6
zxqlVzz0wy2j4kQVUC4ZRZD80IY+4wIiX2YxKBZKGnd2TtPkcJ/ljkUCAwEAAQ==
-----END PUBLIC KEY-----
EOD;

$binary_signature = "";

// At least with PHP 5.2.2 / OpenSSL 0.9.8b (Fedora 7)
// there seems to be no need to call openssl_get_privatekey or similar.
// Just pass the key as defined above
openssl_sign($data, $binary_signature, $private_key, OPENSSL_ALGO_SHA1);

// Check signature
$ok = openssl_verify($data, $binary_signature, $public_key, OPENSSL_ALGO_SHA1);
echo "check #1: ";
if ($ok == 1) {
    echo "signature ok (as it should be)\n";
} elseif ($ok == 0) {
    echo "bad (there's something wrong)\n";
} else {
    echo "ugly, error checking signature\n";
}

$ok = openssl_verify('tampered'.$data, $binary_signature, $public_key, OPENSSL_ALGO_SHA1);
echo "check #2: ";
if ($ok == 1) {
    echo "ERROR: Data has been tampered, but signature is still valid! Argh!\n";
} elseif ($ok == 0) {
    echo "bad signature (as it should be, since data has beent tampered)\n";
} else {
    echo "ugly, error checking signature\n";
}

?>

down

tim at remitone dot com ¶

3 years ago

It should be noted that the default signature algorithm used by openssl_sign() and openssl_verify (OPENSSL_ALGO_SHA1) is no longer supported by default in OpenSSL Version 3 series.

With an up to date OpenSSL library, one has to run
"update-crypto-policies --set LEGACY"
on the server where the library resides in order to allow these functions to work without the optional alternative algorithm argument.

down

sageptr at gmail dot com ¶

10 months ago

Note: to use openssl_sign with ed25519 key in PHP 8.4 (and probably later versions), you need to explicitly pass 0 as algorithm identifier. Omitting this parameter will not work (because this parameter defaults to SHA1), but for some reason there is currently no OPENSSL_ALGO_xxxxx constant for the default signature algorithm.
<?php
  $pkey = openssl_pkey_new(['private_key_type' => OPENSSL_KEYTYPE_ED25519]);
  if (openssl_sign('text', $sig, $pkey, 0)) {
    echo 'Signature successful: ' . bin2hex($sig);
  } else {
    echo 'Signature failed!';
  }
?>