function get_signature($str, $key)
{
$signature = "";
if (function_exists('hash_hmac')) {
$signature = hash_hmac("sha1", $str, $key);
} else {
$signature = custom_hmac("sha1", $str, $key);
}
return $signature;
}
private function __cram_md5_generate($plaintext)
{
#http://hg.dovecot.org/dovecot-1.2/file/84373d238073/src/lib/hmac-md5.c
#http://hg.dovecot.org/dovecot-1.2/file/84373d238073/src/auth/password-scheme.c cram_md5_generate
#am i right that the hmac salt is the plaintext password itself?
$salt = $plaintext;
if (function_exists('hash_hmac')) {
//Some providers doesn't offers hash access.
return hash_hmac('md5', $plaintext, $salt);
} else {
return custom_hmac('md5', $plaintext, $salt);
}
}
public function build_signature($request, $consumer, $token)
{
global $OAuth_last_computed_signature;
$OAuth_last_computed_signature = false;
$base_string = $request->get_signature_base_string();
$request->base_string = $base_string;
$key_parts = array($consumer->secret, $token ? $token->secret : "");
$key_parts = OAuthUtil::urlencode_rfc3986($key_parts);
$key = implode('&', $key_parts);
if (function_exists("hash_hmac")) {
$computed_signature = base64_encode(hash_hmac('sha1', $base_string, $key, true));
} else {
$computed_signature = base64_encode(custom_hmac('sha1', $base_string, $key, true));
}
$OAuth_last_computed_signature = $computed_signature;
return $computed_signature;
}
<?php
set_include_path(dirname(dirname(__FILE__)) . '/lib/');
echo hash_hmac('sha1', $data, $key, false), "\n";
echo custom_hmac('sha1', $data, $key, false), "\n";
function custom_hmac($algo, $data, $key, $raw_output = false)
{
$algo = strtolower($algo);
$pack = 'H' . strlen($algo('test'));
$size = 64;
$opad = str_repeat(chr(0x5c), $size);
$ipad = str_repeat(chr(0x36), $size);
if (strlen($key) > $size) {
$key = str_pad(pack($pack, $algo($key)), $size, chr(0x0));
} else {
$key = str_pad($key, $size, chr(0x0));
}
for ($i = 0; $i < strlen($key) - 1; $i++) {
$opad[$i] = $opad[$i] ^ $key[$i];
$ipad[$i] = $ipad[$i] ^ $key[$i];
}
$output = $algo($opad . pack($pack, $algo($ipad . $data)));
return $raw_output ? pack($pack, $output) : $output;
}
