commit 8314fa5e5c8d300323589ff97599f8f93b847b78 Author: Nick Mathewson nickm@torproject.org Date: Fri Jul 8 15:54:30 2011 -0400
Implement sensible isolation for tunneled directory conns
One-hop dirconn streams all share a session group, and get the ISO_SESSIONGRP flag: they may share circuits with each other and nothing else.
Anonymized dirconn streams get a new internal-use-only ISO_STREAM flag: they may not share circuits with anything, including each other. --- src/or/config.c | 6 +++--- src/or/connection.c | 2 +- src/or/connection_edge.c | 18 ++++++++++++++++-- src/or/connection_edge.h | 2 ++ src/or/directory.c | 8 +++++++- src/or/or.h | 9 +++++++++ 6 files changed, 38 insertions(+), 7 deletions(-)
diff --git a/src/or/config.c b/src/or/config.c index 14acf59..86ccb92 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -4973,7 +4973,7 @@ parse_client_port_config(smartlist_t *out, cfg->type = listener_type; cfg->port = port ? port : defaultport; tor_addr_copy(&cfg->addr, &addr); - cfg->session_group = -1; + cfg->session_group = SESSION_GROUP_UNSET; cfg->isolation_flags = ISO_DEFAULT; smartlist_add(out, cfg); } @@ -4992,7 +4992,7 @@ parse_client_port_config(smartlist_t *out, cfg->type = listener_type; cfg->port = defaultport; tor_addr_from_str(&cfg->addr, defaultaddr); - cfg->session_group = -1; + cfg->session_group = SESSION_GROUP_UNSET; cfg->isolation_flags = ISO_DEFAULT; smartlist_add(out, cfg); } @@ -5006,7 +5006,7 @@ parse_client_port_config(smartlist_t *out, for (; ports; ports = ports->next) { tor_addr_t addr; int port; - int sessiongroup = -1; + int sessiongroup = SESSION_GROUP_UNSET; unsigned isolation = ISO_DEFAULT;
char *addrport; diff --git a/src/or/connection.c b/src/or/connection.c index 5e5abca..0fae11e 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -868,7 +868,7 @@ connection_create_listener(const struct sockaddr *listensockaddr, tor_socket_t s; /* the socket we're going to make */ uint16_t usePort = 0, gotPort = 0; int start_reading = 0; - static int global_next_session_group = -2; + static int global_next_session_group = SESSION_GROUP_FIRST_AUTO;
if (get_n_open_sockets() >= get_options()->_ConnLimit-1) { warn_too_many_conns(); diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index cfa6a3d..42f74b7 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -2497,7 +2497,9 @@ connection_ap_handshake_send_resolve(edge_connection_t *ap_conn) edge_connection_t * connection_ap_make_link(connection_t *partner, char *address, uint16_t port, - const char *digest, int use_begindir, int want_onehop) + const char *digest, + int session_group, int isolation_flags, + int use_begindir, int want_onehop) { edge_connection_t *conn;
@@ -2515,7 +2517,6 @@ connection_ap_make_link(connection_t *partner, conn->socks_request->has_finished = 0; /* waiting for 'connected' */ strlcpy(conn->socks_request->address, address, sizeof(conn->socks_request->address)); - conn->original_dest_address = tor_strdup(address); conn->socks_request->port = port; conn->socks_request->command = SOCKS_COMMAND_CONNECT; conn->want_onehop = want_onehop; @@ -2528,6 +2529,11 @@ connection_ap_make_link(connection_t *partner, digest, DIGEST_LEN); }
+ /* Populate isolation fields. */ + conn->original_dest_address = tor_strdup(address); + conn->session_group = session_group; + conn->isolation_flags = isolation_flags; + conn->_base.address = tor_strdup("(Tor_internal)"); tor_addr_make_unspec(&conn->_base.addr); conn->_base.port = 0; @@ -3291,6 +3297,9 @@ connection_edge_streams_are_compatible(const edge_connection_t *a, tor_strdup(a->socks_request->address); }
+ if (iso & ISO_STREAM) + return 0; + if ((iso & ISO_DESTPORT) && a->socks_request->port != b->socks_request->port) return 0; if ((iso & ISO_DESTADDR) && @@ -3350,6 +3359,11 @@ connection_edge_compatible_with_circuit(const edge_connection_t *conn, tor_strdup(conn->socks_request->address); }
+ /* If isolation_values_set, then the circuit is not compatible with + * any new ISO_STREAM stream. */ + if (iso & ISO_STREAM) + return 0; + if ((iso & ISO_DESTPORT) && conn->socks_request->port != circ->dest_port) return 0; if ((iso & ISO_DESTADDR) && diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h index 8bd308d..85293a0 100644 --- a/src/or/connection_edge.h +++ b/src/or/connection_edge.h @@ -36,6 +36,8 @@ int connection_ap_handshake_send_resolve(edge_connection_t *ap_conn); edge_connection_t *connection_ap_make_link(connection_t *partner, char *address, uint16_t port, const char *digest, + int session_group, + int isolation_flags, int use_begindir, int want_onehop); void connection_ap_handshake_socks_reply(edge_connection_t *conn, char *reply, size_t replylen, diff --git a/src/or/directory.c b/src/or/directory.c index 2667f12..744bc12 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -973,6 +973,10 @@ directory_initiate_command_rend(const char *address, const tor_addr_t *_addr, } } else { /* we want to connect via a tor connection */ edge_connection_t *linked_conn; + /* Anonymized tunneled connections can never share a circuit. + * One-hop directory connections can share circuits with each other + * but nothing else. */ + int iso_flags = anonymized_connection ? ISO_STREAM : ISO_SESSIONGRP;
/* If it's an anonymized connection, remember the fact that we * wanted it for later: maybe we'll want it again soon. */ @@ -988,7 +992,9 @@ directory_initiate_command_rend(const char *address, const tor_addr_t *_addr, linked_conn = connection_ap_make_link(TO_CONN(conn), conn->_base.address, conn->_base.port, - digest, use_begindir, conn->dirconn_direct); + digest, + SESSION_GROUP_DIRCONN, iso_flags, + use_begindir, conn->dirconn_direct); if (!linked_conn) { log_warn(LD_NET,"Making tunnel to dirserver failed."); connection_mark_for_close(TO_CONN(conn)); diff --git a/src/or/or.h b/src/or/or.h index ace92ce..26e9970 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -2642,11 +2642,20 @@ typedef enum invalid_router_usage_t { #define ISO_SESSIONGRP (1u<<5) /** Isolate based on newnym epoch (always on). */ #define ISO_NYM_EPOCH (1u<<6) +/** Isolate all streams (Internal only). */ +#define ISO_STREAM (1u<<7) /**@}*/
/** Default isolation level for ports. */ #define ISO_DEFAULT (ISO_CLIENTADDR|ISO_SOCKSAUTH|ISO_SESSIONGRP|ISO_NYM_EPOCH)
+/** Indicates that we haven't yet set a session group on a port_cfg_t. */ +#define SESSION_GROUP_UNSET -1 +/** Session group reserved for directory connections */ +#define SESSION_GROUP_DIRCONN -2 +/** First automatically allocated session group number */ +#define SESSION_GROUP_FIRST_AUTO -3 + /** Configuration for a single port that we're listening on. */ typedef struct port_cfg_t { tor_addr_t addr; /**< The actual IP to listen on, if !is_unix_addr. */