openssl_sign
(PHP 4 >= 4.0.4, PHP 5)
openssl_sign — Generate signature
Description
$data
, string &$signature
, mixed $priv_key_id
[, mixed $signature_alg = OPENSSL_ALGO_SHA1
] )
openssl_sign() computes a signature for the
specified data by generating a cryptographic
digital signature using the private key associated with
priv_key_id. Note that the data itself is
not encrypted.
Parameters
-
data -
The string of data you wish to sign
-
signature -
If the call was successful the signature is returned in
signature. -
priv_key_id -
resource - a key, returned by openssl_get_privatekey()
string - a PEM formatted key
-
signature_alg -
int - one of these Signature Algorithms.
string - a valid string returned by openssl_get_md_methods() example, "sha256WithRSAEncryption" or "sha384".
Return Values
Returns TRUE on success or FALSE on failure.
Changelog
| Version | Description |
|---|---|
| 5.0.0 |
The signature_alg parameter was added.
|
Examples
Example #1 openssl_sign() example
<?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);
?>
Example #2 openssl_sign() example
<?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);
?>
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Криптографические расширения
- OpenSSL
- openssl_cipher_iv_length
- openssl_csr_export_to_file
- openssl_csr_export
- openssl_csr_get_public_key
- openssl_csr_get_subject
- openssl_csr_new
- openssl_csr_sign
- openssl_decrypt
- openssl_dh_compute_key
- openssl_digest
- openssl_encrypt
- openssl_error_string
- openssl_free_key
- openssl_get_cert_locations
- openssl_get_cipher_methods
- openssl_get_md_methods
- openssl_get_privatekey
- openssl_get_publickey
- openssl_open
- openssl_pbkdf2
- openssl_pkcs12_export_to_file
- openssl_pkcs12_export
- openssl_pkcs12_read
- openssl_pkcs7_decrypt
- openssl_pkcs7_encrypt
- openssl_pkcs7_sign
- openssl_pkcs7_verify
- openssl_pkey_export_to_file
- openssl_pkey_export
- openssl_pkey_free
- openssl_pkey_get_details
- openssl_pkey_get_private
- openssl_pkey_get_public
- openssl_pkey_new
- openssl_private_decrypt
- openssl_private_encrypt
- openssl_public_decrypt
- openssl_public_encrypt
- openssl_random_pseudo_bytes
- openssl_seal
- openssl_sign
- openssl_spki_export_challenge
- openssl_spki_export
- openssl_spki_new
- openssl_spki_verify
- openssl_verify
- openssl_x509_check_private_key
- openssl_x509_checkpurpose
- openssl_x509_export_to_file
- openssl_x509_export
- openssl_x509_fingerprint
- openssl_x509_free
- openssl_x509_parse
- openssl_x509_read
Коментарии
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";
}
?>
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.