r16409@catbus: nickm | 2007-11-05 10:38:25 -0500

 Split handshake state into its own structure.  Revise versions and netinfo code to use this structure.


svn:r12380

1 files changed, 64 insertions, 28 deletions

diff --git a/src/or/command.c b/src/or/command.c
index c449e6c0a0..e667d5e0a6 100644
--- a/src/or/command.c
+++ b/src/or/command.c
@@ -396,12 +396,14 @@ command_process_versions_cell(cell_t *cell, or_connection_t *conn)
   int highest_supported_version = 0;
   const char *cp, *end;
   if (conn->link_proto != 0 ||
-      conn->_base.state != OR_CONN_STATE_WAITING_FOR_VERSIONS) {
+      conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING ||
+      (conn->handshake_state && conn->handshake_state->received_versions)) {
     log_fn(LOG_PROTOCOL_WARN, LD_OR,
            "Received a VERSIONS cell on a connection with its version "
            "already set to %d; dropping", (int) conn->link_proto);
     return;
   }
+  tor_assert(conn->handshake_state);
   versionslen = ntohs(get_uint16(cell->payload));
   end = cell->payload + 2 + versionslen;
   if (end > cell->payload + CELL_PAYLOAD_SIZE)
@@ -416,12 +418,12 @@ command_process_versions_cell(cell_t *cell, or_connection_t *conn)
   if (!highest_supported_version) {
     log_fn(LOG_PROTOCOL_WARN, LD_OR,
            "Couldn't find a version in common; defaulting to v1.");
-    /*XXXX020 or just break the connection?*/
+    /*XXXX020 just break the connection?*/
     conn->link_proto = 1;
     return;
   }
   conn->link_proto = highest_supported_version;
-  conn->_base.state = OR_CONN_STATE_OPEN;
+  conn->handshake_state->received_versions = 1;
 
   if (highest_supported_version >= 2)
     connection_or_send_netinfo(conn);
@@ -438,46 +440,42 @@ command_process_netinfo_cell(cell_t *cell, or_connection_t *conn)
   const char *cp, *end;
   uint8_t n_other_addrs;
   time_t now = time(NULL);
-
-  /*XXXX020 reject duplicate netinfos. */
-
-  if (conn->link_proto < 2 || conn->_base.state != OR_CONN_STATE_OPEN) {
+  if (conn->link_proto < 2) {
     log_fn(LOG_PROTOCOL_WARN, LD_OR,
            "Received a NETINFO cell on %s connection; dropping.",
            conn->link_proto == 0 ? "non-versioned" : "a v1");
     return;
   }
+  if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING) {
+    log_fn(LOG_PROTOCOL_WARN, LD_OR,
+           "Received a NETINFO cell on a non-handshaking; dropping.");
+    return;
+  }
+  tor_assert(conn->handshake_state &&
+             conn->handshake_state->received_versions);
+  if (conn->handshake_state->received_netinfo) {
+    log_fn(LOG_PROTOCOL_WARN, LD_OR,
+           "Received a duplicate NETINFO cell; dropping.");
+    return;
+  }
   /* Decode the cell. */
   timestamp = ntohl(get_uint32(cell->payload));
+  if (abs(now - conn->handshake_state->sent_versions_at) < 180) {
+    conn->handshake_state->apparent_skew = now - timestamp;
+  }
+
   my_addr_type = (uint8_t) cell->payload[4];
   my_addr_len = (uint8_t) cell->payload[5];
   my_addr_ptr = cell->payload + 6;
-  /* Possibly learn my address. XXXX020 */
   end = cell->payload + CELL_PAYLOAD_SIZE;
   cp = cell->payload + 6 + my_addr_len;
   if (cp >= end) {
     log_fn(LOG_PROTOCOL_WARN, LD_OR,
            "Address too long in netinfo cell; dropping.");
+    /*XXXX020 reject and break OR conn! */
     return;
-  }
-
-  /*XXXX020 magic number 3600 */
-  if (abs(timestamp - now) > 3600 &&
-      router_get_by_digest(conn->identity_digest)) {
-    long delta = now - timestamp;
-    char dbuf[64];
-    /*XXXX020 not always warn!*/
-    format_time_interval(dbuf, sizeof(dbuf), delta);
-    log_fn(LOG_WARN, LD_HTTP, "Received NETINFO cell with skewed time from "
-           "server at %s:%d.  It seems that our clock is %s by %s, or "
-           "that theirs is %s. Tor requires an accurate clock to work: "
-           "please check your time and date settings.",
-           conn->_base.address, (int)conn->_base.port,
-           delta>0 ? "ahead" : "behind", dbuf,
-           delta>0 ? "behind" : "ahead");
-    control_event_general_status(LOG_WARN,
-                                 "CLOCK_SKEW SKEW=%ld SOURCE=OR:%s:%d",
-                                 delta, conn->_base.address, conn->_base.port);
+  } else if (my_addr_type == RESOLVED_TYPE_IPV4 && my_addr_len == 4) {
+    conn->handshake_state->my_apparent_addr = ntohl(get_uint32(my_addr_ptr));
   }
 
   n_other_addrs = (uint8_t) *cp++;
@@ -491,12 +489,50 @@ command_process_netinfo_cell(cell_t *cell, or_connection_t *conn)
     if (other_addr_type == RESOLVED_TYPE_IPV4 && other_addr_len == 4) {
       uint32_t addr = ntohl(get_uint32(cp));
       if (addr == conn->real_addr) {
-        conn->is_canonical = 1;
+        conn->handshake_state->apparently_canonical = 1;
         break;
       }
     }
     cp += other_addr_len;
     --n_other_addrs;
   }
+
+  conn->handshake_state->received_netinfo = 1;
 }
 
+/** DOCDOC Called when we're done authenticating; act on stuff we
+ * learned in netinfo. */
+void
+connection_or_act_on_netinfo(or_connection_t *conn)
+{
+  long delta;
+  if (!conn->handshake_state)
+    return;
+
+  tor_assert(conn->handshake_state->authenticated != 0);
+
+  delta = conn->handshake_state->apparent_skew;
+  /*XXXX020 magic number 3600 */
+  if (abs(delta) > 3600 &&
+      router_get_by_digest(conn->identity_digest)) {
+    char dbuf[64];
+    /*XXXX020 not always warn!*/
+    format_time_interval(dbuf, sizeof(dbuf), delta);
+    log_fn(LOG_WARN, LD_HTTP, "Received NETINFO cell with skewed time from "
+           "server at %s:%d.  It seems that our clock is %s by %s, or "
+           "that theirs is %s. Tor requires an accurate clock to work: "
+           "please check your time and date settings.",
+           conn->_base.address, (int)conn->_base.port,
+           delta>0 ? "ahead" : "behind", dbuf,
+           delta>0 ? "behind" : "ahead");
+    control_event_general_status(LOG_WARN,
+                                 "CLOCK_SKEW SKEW=%ld SOURCE=OR:%s:%d",
+                                 delta, conn->_base.address, conn->_base.port);
+  }
+
+  /* XXX020 possibly, learn my address from my_apparent_addr */
+
+  if (conn->handshake_state->apparently_canonical) {
+    conn->is_canonical = 1;
+  }
+}