Check non-onion hostnames & IP addresses against client port flags

Check NoDNSRequest, NoIPv4Traffic, and NoIPv6Traffic before
attaching a stream.

NoDNSRequest refuses connections to all non-onion hostnames,
but permits IP addresses.
NoIPv4Traffic refuses connections to IPv4 addresses, but resolves
hostnames.
NoIPv6Traffic refuses connections to IPv6 addresses, but resolves
hostnames.

Combined, they refuse all non-onion hostnames and IP addresses.
This commit is contained in:
teor (Tim Wilson-Brown)
2016-04-01 00:22:17 +11:00
committed by David Goulet
parent 45b4e63519
commit b311f82026
+47
View File
@@ -1474,6 +1474,53 @@ connection_ap_handshake_rewrite_and_attach(entry_connection_t *conn,
}
#endif
/* socks->address is a non-onion hostname or IP address.
* If we can't do any non-onion requests, refuse the connection.
* If we have a hostname but can't do DNS, refuse the connection.
* If we have an IP address, but we can't use that address family,
* refuse the connection.
*
* If we can do DNS requests, and we can use at least one address family,
* then we have to resolve the address first. Then we'll know if it
* resolves to a usable address family. */
/* First, check if all non-onion traffic is disabled */
if (!conn->entry_cfg.dns_request && !conn->entry_cfg.ipv4_traffic
&& !conn->entry_cfg.ipv6_traffic) {
log_warn(LD_APP, "Refusing to connect to non-hidden-service hostname "
"or IP address %s because Port has OnionTrafficOnly set (or "
"NoDNSRequest, NoIPv4Traffic, and NoIPv6Traffic).",
safe_str_client(socks->address));
connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
return -1;
}
/* Then check if we have a hostname or IP address, and whether DNS or
* the IP address family are permitted */
tor_addr_t dummy_addr;
int socks_family = tor_addr_parse(&dummy_addr, socks->address);
/* family will be -1 for a non-onion hostname that's not an IP */
if (socks_family == -1 && !conn->entry_cfg.dns_request) {
log_warn(LD_APP, "Refusing to connect to hostname %s "
"because Port has NoDNSRequest set.",
safe_str_client(socks->address));
connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
return -1;
} else if (socks_family == AF_INET && !conn->entry_cfg.ipv4_traffic) {
log_warn(LD_APP, "Refusing to connect to IPv4 address %s because "
"Port has NoIPv4Traffic set.",
safe_str_client(socks->address));
connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
return -1;
} else if (socks_family == AF_INET6 && !conn->entry_cfg.ipv6_traffic) {
log_warn(LD_APP, "Refusing to connect to IPv6 address %s because "
"Port has NoIPv6Traffic set.",
safe_str_client(socks->address));
connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
return -1;
}
/* No else, we've covered all possible returned value. */
/* See if this is a hostname lookup that we can answer immediately.
* (For example, an attempt to look up the IP address for an IP address.)
*/