Merge abc9ff2 into 0a86f14

changes/bug29034

@@ -0,0 +1,5 @@
+  o Major bugfixes (Onion service reachability):
+    - Properly clean up the introduction point map and associated state when
+      circuits change purpose from onion service circuits to pathbias,
+      measurement, or other circuit types. This should fix some instances of
+      introduction point failure. Fixes bug 29034; bugfix on 0.3.2.1-alpha.

scripts/maint/practracker/exceptions.txt

@@ -92,7 +92,7 @@ problem function-size /src/core/or/circuitlist.c:circuits_handle_oom() 117
 problem function-size /src/core/or/circuitmux.c:circuitmux_set_policy() 110
 problem function-size /src/core/or/circuitmux.c:circuitmux_attach_circuit() 114
 problem function-size /src/core/or/circuitstats.c:circuit_build_times_parse_state() 124
-problem file-size /src/core/or/circuituse.c 3156
+problem file-size /src/core/or/circuituse.c 3162
 problem function-size /src/core/or/circuituse.c:circuit_is_acceptable() 133
 problem function-size /src/core/or/circuituse.c:circuit_expire_building() 394
 problem function-size /src/core/or/circuituse.c:circuit_log_ancient_one_hop_circuits() 126

src/core/or/circuituse.c

@@ -3068,6 +3068,12 @@ circuit_change_purpose(circuit_t *circ, uint8_t new_purpose)
 
   if (circ->purpose == new_purpose) return;
 
+  /* Take specific actions if we are repurposing a hidden service circuit. */
+  if (circuit_purpose_is_hidden_service(circ->purpose) &&
+      !circuit_purpose_is_hidden_service(new_purpose)) {
+    hs_circ_repurpose(circ);
+  }
+
   if (CIRCUIT_IS_ORIGIN(circ)) {
     char old_purpose_desc[80] = "";
 

src/feature/hs/hs_circuit.c

@@ -25,6 +25,7 @@
 #include "feature/nodelist/describe.h"
 #include "feature/nodelist/nodelist.h"
 #include "feature/rend/rendservice.h"
+#include "feature/rend/rendcommon.h"
 #include "feature/stats/rephist.h"
 #include "lib/crypt_ops/crypto_dh.h"
 #include "lib/crypt_ops/crypto_rand.h"
@@ -1192,3 +1193,33 @@ hs_circ_cleanup(circuit_t *circ)
     hs_circuitmap_remove_circuit(circ);
   }
 }
+
+/* The given circuit will be repurposed so take the appropriate actions. A
+ * cleanup from the HS maps and of all HS related structures is done.
+ *
+ * Once this function returns, the circuit can be safely repurposed. */
+void
+hs_circ_repurpose(circuit_t *circ)
+{
+  origin_circuit_t *origin_circ;
+
+  tor_assert(circ);
+
+  /* Only repurposing an origin circuit is possible for HS. */
+  if (!CIRCUIT_IS_ORIGIN(circ)) {
+    return;
+  }
+  origin_circ = TO_ORIGIN_CIRCUIT(circ);
+
+  /* First, cleanup the circuit from the HS maps. */
+  hs_circ_cleanup(circ);
+
+  /* Depending on the version, different cleanup is done. */
+  if (origin_circ->rend_data) {
+    /* v2. */
+    rend_circ_cleanup(origin_circ);
+  } else if (origin_circ->hs_ident) {
+    /* v3. */
+    hs_ident_circuit_free(origin_circ->hs_ident);
+  }
+}

src/feature/hs/hs_circuit.h

@@ -16,6 +16,7 @@
 
 /* Cleanup function when the circuit is closed or/and freed. */
 void hs_circ_cleanup(circuit_t *circ);
+void hs_circ_repurpose(circuit_t *circ);
 
 /* Circuit API. */
 int hs_circ_service_intro_has_opened(hs_service_t *service,

src/feature/rend/rendcommon.c

@@ -1046,3 +1046,14 @@ rend_circuit_pk_digest_eq(const origin_circuit_t *ocirc,
  match:
   return 1;
 }
+
+/* Cleanup the given circuit of all HS v2 data structure. */
+void
+rend_circ_cleanup(origin_circuit_t *circ)
+{
+  tor_assert(circ);
+
+  /* Both fields are set to NULL with these. */
+  crypto_pk_free(circ->intro_key);
+  rend_data_free(circ->rend_data);
+}

src/feature/rend/rendcommon.h

@@ -71,6 +71,8 @@ int rend_non_anonymous_mode_enabled(const or_options_t *options);
 void assert_circ_anonymity_ok(const origin_circuit_t *circ,
                               const or_options_t *options);
 
+void rend_circ_cleanup(origin_circuit_t *circ);
+
 #ifdef RENDCOMMON_PRIVATE
 
 STATIC int