sign.php

<?php

$ip = 'dev.uc-itcom.ru';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://' . $ip . '/app/index.php/gateway/ofdApi/sign');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, '<xml>
    <login>semenov_278</login>
    <password>x8XUo6z0</password>
    <base64Data>cGFzc3dvcmQ=</base64Data>
    <type>CAdES</type>
    <idItk>278</idItk>
</xml>');

curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);

$out = curl_exec($ch);

if ($out === false) {
    $errot = curl_error($ch);
    throw new Exception('Ошибка CURL: ' . curl_error($ch), 500);
}


$data = simplexml_load_string($out);

var_dump($data->result);