function testMajority($results, $signedData, $myPair = null, $inGroup = null, $error = true)
{
// Get the set of root public keys, indexed by endpoint. Note that they are raw bytes:
$publicKeys = getRootKeys($inGroup);
// How many are there?
$nodesInRoot = count($publicKeys);
if ($nodesInRoot < 3) {
// This root isn't big enough. It's not able to obtain a majority.
return false;
}
// The number of root nodes that we have successfully verified a response from.
// The JSON to forward to other nodes. This only occurs when myPair is not null (which indicates
// that this server is 'leading' the majority process).
$fullSet = '';
if ($myPair == NULL) {
// We start with 0 - we have to verify all signatures, including our own.
$verifiedCount = 0;
} else {
global $thisEntity;
// It starts with 1 because we know at least this ones signature was successful.
$verifiedCount = 1;
// This route also generates JSON to forward to other nodes too.
$fullSet = '{"' . $thisEntity['Endpoint'] . '":' . $myPair;
}
foreach ($results as $endPoint => $result) {
// Get this endpoints public key (bytes):
if (!isset($publicKeys[$endPoint])) {
continue;
}
// Get the key:
$endpointKey = $publicKeys[$endPoint];
if (is_array($result)) {
// JSON is already loaded.
$resultJson =& $result;
// Encode it to a string:
$result = json_encode($resultJson);
} else {
// Load the JSON:
$resultJson = json_decode($result, true);
}
// Get the signature (base64):
$resultSig = $resultJson['signature'];
// Verify it:
if (verify($resultSig, $resultJson['challenge'] . $signedData, $endpointKey)) {
// Increase the count!
$verifiedCount++;
if ($fullSet != '') {
// Output the end point plus the JSON response:
$fullSet .= ',"' . $endPoint . '":' . $result;
}
}
}
// Finish the full set:
if ($fullSet != '') {
$fullSet .= '}';
}
// The important check occurs here - do we have a majority? Must be greater than half.
if ($verifiedCount > $nodesInRoot / 2) {
// Majority formed!
if ($fullSet == '') {
return true;
}
return $fullSet;
} else {
if ($error) {
// No majority formed.
error('majority/notformed');
}
}
// No majority formed (silent error).
return false;
}
function sendToRoot($payload, $pHeader, $decodeJson = false, $location = null, $rootGroup = null)
{
global $thisEntity, $path, $dz, $rootKeys;
if ($location == null) {
// Use the current path as the location (used by forwarding):
$location = $path;
}
// Build the message:
$message = '{"header":{"entity":"' . $thisEntity['Endpoint'] . '"},"protected":"' . $pHeader . '","payload":"' . $payload . '","signature":"' . base64_encode(sign($pHeader . '.' . $payload)) . '"}';
// Forward to all other root nodes in my group.
$group = $thisEntity['Group'];
// The responses:
$responses = array();
// Are we using this group or another one?
if ($rootGroup == null) {
// Get the local root keys:
if ($rootKeys == null) {
// Root keys holds a mapping of endpoint to key.
// We'll use it here to get those endpoints.
getRootKeys();
}
// Use this group:
$keySet = $rootKeys;
} else {
// Sending to some other root group.
// Only need to send to one node here.
// (If we send to all of them, it defeats the object of having groups!)
// Get a random node:
$randomRow = randomRoot($rootGroup);
// Create the set:
$keySet = array();
// Add our single entry to it:
$keySet[$randomRow['Endpoint']] = $randomRow['Key'];
}
global $rootErrors;
// Clear root errors:
$rootErrors = null;
// For each one..
foreach ($keySet as $endPoint => $rootKey) {
if ($endPoint == $thisEntity['Endpoint']) {
// Don't send to myself!
continue;
}
// Send it a message:
// Warning! This will take a while with crowded roots
// as it does the requests one after another. Use parallel requests instead.
$error;
$response = post('https://' . $endPoint . '/' . $location, $message, $error);
// Got a response?
if ($error) {
// The remote node emitted an error.
if (!$rootErrors) {
$rootErrors = array();
}
// Add the error:
array_push($rootErrors, $error);
} else {
if ($decodeJson) {
// Add to result:
$responses[$endPoint] = json_decode($response, true);
} else {
// Add to result as-is (default):
$responses[$endPoint] = $response;
}
}
}
// Return the responses:
return $responses;
}
