Merge remote-tracking branch 'ahf-github/asn/bugs4700_2'

3 files changed, 56 insertions, 0 deletions

diff --git a/src/core/or/connection_edge.c b/src/core/or/connection_edge.c
index 40772670ee..d0fad67009 100644
--- a/src/core/or/connection_edge.c
+++ b/src/core/or/connection_edge.c
@@ -839,6 +839,46 @@ connected_cell_format_payload(uint8_t *payload_out,
   return connected_payload_len;
 }
 
+/* This is an onion service client connection: Export the client circuit ID
+ * according to the HAProxy proxy protocol. */
+STATIC void
+export_hs_client_circuit_id(edge_connection_t *edge_conn,
+                            hs_circuit_id_protocol_t protocol)
+{
+  /* We only support HAProxy right now. */
+  if (protocol != HS_CIRCUIT_ID_PROTOCOL_HAPROXY)
+    return;
+
+  char *buf = NULL;
+  const char dst_ipv6[] = "::1";
+  /* See RFC4193 regarding fc00::/7 */
+  const char src_ipv6_prefix[] = "fc00:dead:beef:4dad:";
+  uint16_t dst_port = 0;
+  uint16_t src_port = 1; /* default value */
+  uint32_t gid = 0; /* default value */
+
+  /* Generate a GID and source port for this client */
+  if (edge_conn->on_circuit != NULL) {
+    gid = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit)->global_identifier;
+    src_port = gid & 0x0000ffff;
+  }
+
+  /* Grab the original dest port from the hs ident */
+  if (edge_conn->hs_ident) {
+    dst_port = edge_conn->hs_ident->orig_virtual_port;
+  }
+
+  /* Build the string */
+  tor_asprintf(&buf, "PROXY TCP6 %s:%x:%x %s %d %d\r\n",
+               src_ipv6_prefix,
+               gid >> 16, gid & 0x0000ffff,
+               dst_ipv6, src_port, dst_port);
+
+  connection_buf_add(buf, strlen(buf), TO_CONN(edge_conn));
+
+  tor_free(buf);
+}
+
 /** Connected handler for exit connections: start writing pending
  * data, deliver 'CONNECTED' relay cells as appropriate, and check
  * any pending data that may have been received. */
@@ -859,6 +899,7 @@ connection_edge_finished_connecting(edge_connection_t *edge_conn)
   rep_hist_note_exit_stream_opened(conn->port);
 
   conn->state = EXIT_CONN_STATE_OPEN;
+
   connection_watch_events(conn, READ_EVENT); /* stop writing, keep reading */
   if (connection_get_outbuf_len(conn)) /* in case there are any queued relay
                                         * cells */
@@ -3652,6 +3693,14 @@ handle_hs_exit_conn(circuit_t *circ, edge_connection_t *conn)
 
   hs_inc_rdv_stream_counter(origin_circ);
 
+  /* If it's an onion service connection, we might want to include the proxy
+   * protocol header: */
+  if (conn->hs_ident) {
+    hs_circuit_id_protocol_t circuit_id_protocol =
+      hs_service_exports_circuit_id(&conn->hs_ident->identity_pk);
+    export_hs_client_circuit_id(conn, circuit_id_protocol);
+  }
+
   /* Connect tor to the hidden service destination. */
   connection_exit_connect(conn);
 
diff --git a/src/core/or/connection_edge.h b/src/core/or/connection_edge.h
index 71ea95d6e5..6dee93f1f9 100644
--- a/src/core/or/connection_edge.h
+++ b/src/core/or/connection_edge.h
@@ -14,6 +14,8 @@
 
 #include "lib/testsupport/testsupport.h"
 
+#include "feature/hs/hs_service.h"
+
 edge_connection_t *TO_EDGE_CONN(connection_t *);
 entry_connection_t *TO_ENTRY_CONN(connection_t *);
 entry_connection_t *EDGE_TO_ENTRY_CONN(edge_connection_t *);
@@ -260,6 +262,10 @@ STATIC void connection_ap_handshake_rewrite(entry_connection_t *conn,
                                             rewrite_result_t *out);
 
 STATIC int connection_ap_process_http_connect(entry_connection_t *conn);
+STATIC void
+export_hs_client_circuit_id(edge_connection_t *edge_conn,
+                            hs_circuit_id_protocol_t protocol);
+
 #endif /* defined(CONNECTION_EDGE_PRIVATE) */
 
 #endif /* !defined(TOR_CONNECTION_EDGE_H) */
diff --git a/src/core/or/or.h b/src/core/or/or.h
index 4d8b6d7871..7557c1321e 100644
--- a/src/core/or/or.h
+++ b/src/core/or/or.h
@@ -26,6 +26,7 @@
 #include "lib/cc/compat_compiler.h"
 #include "lib/cc/torint.h"
 #include "lib/container/map.h"
+#include "lib/container/buffers.h"
 #include "lib/container/smartlist.h"
 #include "lib/crypt_ops/crypto_cipher.h"
 #include "lib/crypt_ops/crypto_rsa.h"