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Last updated: Tue, 19 Sep 2006


(PHP 4 >= 4.0.4, PHP 5)

openssl_sign -- Generate signature


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

Returns TRUE on success or FALSE on failure. If successful the signature is returned in signature.

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.

Note: Optional 4th parameter signature_alg was added in version 5.0.0. Its default value is OPENSSL_ALGO_SHA1. For more information see the list of Signature Algorithms.

Example 1. openssl_sign() example

// $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);
$pkeyid = openssl_get_privatekey($priv_key);

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

// free the key from memory

See also openssl_verify().

Last updated: Tue, 19 Sep 2006