OpenSSL 函数
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PHP手册

openssl_sign

(PHP 4 >= 4.0.4, PHP 5)

openssl_sign — Generate signature

说明

bool openssl_sign ( string $data , string &$signature , mixed $priv_key_id [, int $signature_alg = OPENSSL_ALGO_SHA1 ] )

openssl_sign() computes a signature for the specified data by using SHA1 for hashing followed by encryption using the private key associated with priv_key_id. Note that the data itself is not encrypted.

参数

data

signature

If the call was successful the signature is returned in signature.

priv_key_id

signature_alg

For more information see the list of Signature Algorithms.

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
5.0.0 The signature_alg parameter was added.

范例

Example #1 openssl_sign() example

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

// fetch private key from file and ready it
$fp = fopen("/src/openssl-0.9.6/demos/sign/key.pem", "r");
$priv_key = fread($fp, 8192);
fclose($fp);
$pkeyid = openssl_get_privatekey($priv_key);

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

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

参见

OpenSSL 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: Generate signature

用户评论:

Chris Kistner (20-Jul-2010 01:53)

The list of Signature Algorithms (constants) is very limited! Fortunately the newer versions of php/openssl allow you to specify the signature algorithm as a string.

You can use the 'openssl_get_md_methods' method to get a list of digest methods. Only some of them may be used to sign with RSA private keys.

Those that can be used to sign with RSA private keys are: md4, md5, ripemd160, sha, sha1, sha224, sha256, sha384, sha512

Here's the modified Example #1 with SHA-512 hash:
<?php
// $data is assumed to contain the data to be signed

// fetch private key from file and ready it
$fp = fopen("/src/openssl-0.9.6/demos/sign/key.pem", "r");
$priv_key = fread($fp, 8192);
fclose($fp);
$pkeyid = openssl_get_privatekey($priv_key);

// compute signature with SHA-512
openssl_sign($data, $signature, $pkeyid, "sha512");

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

edmarw at yahoo dot com (04-Sep-2007 05:22)

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";
}

?>

adam dot mansfeld at gmail dot com (19-Oct-2005 08:50)

Hello,

the fourth parameter 'signature_alg' to choose the signature algorithm can be one of:

OPENSSL_ALGO_SHA1
OPENSSL_ALGO_MD5
OPENSSL_ALGO_MD4
OPENSSL_ALGO_MD2

Just for the case that somebody needs this.

Regards