prop224: Add client-side rend circuit support to HS circuitmap

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/or/hs_circuitmap.c

@@ -5,8 +5,10 @@
  * \file hs_circuitmap.c
  *
  * \brief Hidden service circuitmap: A hash table that maps binary tokens to
- *  introduction and rendezvous circuits; it's used both by relays acting as
+ *  introduction and rendezvous circuits; it's used:
- *  intro points and rendezvous points, and also by hidden services themselves.
+ *  (a) by relays acting as intro points and rendezvous points
+ *  (b) by hidden services to find intro and rend circuits and
+ *  (c) by HS clients to find rendezvous circuits.
  **/
 
 #define HS_CIRCUITMAP_PRIVATE
@@ -404,6 +406,29 @@ hs_circuitmap_get_rend_circ_service_side(const uint8_t *cookie)
   return circ;
 }
 
+/* Public function: Return client-side rendezvous circuit with rendezvous
+ * <b>cookie</b>. It will first lookup for the CIRCUIT_PURPOSE_C_REND_READY
+ * purpose and then try for CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED.
+ *
+ * Return NULL if no such circuit is found in the circuitmap. */
+origin_circuit_t *
+hs_circuitmap_get_rend_circ_client_side(const uint8_t *cookie)
+{
+  origin_circuit_t *circ = NULL;
+
+  circ = hs_circuitmap_get_origin_circuit(HS_TOKEN_REND_CLIENT_SIDE,
+                                          REND_TOKEN_LEN, cookie,
+                                          CIRCUIT_PURPOSE_C_REND_READY);
+  if (circ) {
+    return circ;
+  }
+
+  circ = hs_circuitmap_get_origin_circuit(HS_TOKEN_REND_CLIENT_SIDE,
+                                          REND_TOKEN_LEN, cookie,
+                                 CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED);
+  return circ;
+}
+
 /**** Public servide-side setters: */
 
 /* Public function: Register v2 intro circuit with key <b>digest</b> to the
@@ -439,6 +464,22 @@ hs_circuitmap_register_rend_circ_service_side(origin_circuit_t *circ,
                                  REND_TOKEN_LEN, cookie);
 }
 
+/* Public function: Register rendezvous circuit with key <b>cookie</b> to the
+ * client-side circuitmap. */
+void
+hs_circuitmap_register_rend_circ_client_side(origin_circuit_t *or_circ,
+                                             const uint8_t *cookie)
+{
+  circuit_t *circ = TO_CIRCUIT(or_circ);
+  { /* Basic circ purpose sanity checking */
+    tor_assert_nonfatal(circ->purpose == CIRCUIT_PURPOSE_C_REND_READY ||
+                    circ->purpose == CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED);
+  }
+
+  hs_circuitmap_register_circuit(circ, HS_TOKEN_REND_CLIENT_SIDE,
+                                 REND_TOKEN_LEN, cookie);
+}
+
 /**** Misc public functions: */
 
 /** Public function: Remove this circuit from the HS circuitmap. Clear its HS

src/or/hs_circuitmap.h

@@ -43,6 +43,8 @@ struct origin_circuit_t *
 hs_circuitmap_get_intro_circ_v2_service_side(const uint8_t *digest);
 struct origin_circuit_t *
 hs_circuitmap_get_rend_circ_service_side(const uint8_t *cookie);
+struct origin_circuit_t *
+hs_circuitmap_get_rend_circ_client_side(const uint8_t *cookie);
 
 void hs_circuitmap_register_intro_circ_v2_service_side(
                                         struct origin_circuit_t *circ,
@@ -53,6 +55,9 @@ void hs_circuitmap_register_intro_circ_v3_service_side(
 void hs_circuitmap_register_rend_circ_service_side(
                                         struct origin_circuit_t *circ,
                                         const uint8_t *cookie);
+void hs_circuitmap_register_rend_circ_client_side(
+                                      struct origin_circuit_t *circ,
+                                      const uint8_t *cookie);
 
 void hs_circuitmap_remove_circuit(struct circuit_t *circ);
 
@@ -76,6 +81,9 @@ typedef enum {
   HS_TOKEN_INTRO_V2_SERVICE_SIDE,
   /** A v3 introduction point pubkey on a hidden service (256bit) */
   HS_TOKEN_INTRO_V3_SERVICE_SIDE,
+
+  /** A rendezvous cookie on the client side (128bit) */
+  HS_TOKEN_REND_CLIENT_SIDE,
 } hs_token_type_t;
 
 /** Represents a token used in the HS protocol. Each such token maps to a

src/test/test_circuitlist.c

@@ -180,6 +180,7 @@ static void
 test_rend_token_maps(void *arg)
 {
   or_circuit_t *c1, *c2, *c3, *c4;
+  origin_circuit_t *c5;
   const uint8_t tok1[REND_TOKEN_LEN] = "The cat can't tell y";
   const uint8_t tok2[REND_TOKEN_LEN] = "ou its name, and it ";
   const uint8_t tok3[REND_TOKEN_LEN] = "doesn't really care.";
@@ -194,6 +195,7 @@ test_rend_token_maps(void *arg)
   c2 = or_circuit_new(0, NULL);
   c3 = or_circuit_new(0, NULL);
   c4 = or_circuit_new(0, NULL);
+  c5 = origin_circuit_new();
 
   /* Make sure we really filled up the tok* variables */
   tt_int_op(tok1[REND_TOKEN_LEN-1], OP_EQ, 'y');
@@ -264,6 +266,13 @@ test_rend_token_maps(void *arg)
   tt_ptr_op(TO_CIRCUIT(c4)->hs_token, OP_EQ, NULL);
   tt_ptr_op(NULL, OP_EQ, hs_circuitmap_get_intro_circ_v2_relay_side(tok3));
 
+  /* Now let's do a check for the client-side rend circuitmap */
+  c5->base_.purpose = CIRCUIT_PURPOSE_C_REND_READY;
+  hs_circuitmap_register_rend_circ_client_side(c5, tok1);
+
+  tt_ptr_op(c5, OP_EQ, hs_circuitmap_get_rend_circ_client_side(tok1));
+  tt_ptr_op(NULL, OP_EQ, hs_circuitmap_get_rend_circ_client_side(tok2));
+
  done:
   if (c1)
     circuit_free(TO_CIRCUIT(c1));
@@ -273,6 +282,8 @@ test_rend_token_maps(void *arg)
     circuit_free(TO_CIRCUIT(c3));
   if (c4)
     circuit_free(TO_CIRCUIT(c4));
+  if (c5)
+    circuit_free(TO_CIRCUIT(c5));
 }
 
 static void