From 588794771fdaf7cd129efb2043fb58572c8b04ca Mon Sep 17 00:00:00 2001
From: David Goulet <dgoulet@torproject.org>
Date: Wed, 30 Oct 2019 14:26:21 -0400
Subject: [PATCH] circ: Add hidden service helper functions

Functions to correctly identify HS circuit type and version.

Part of #32020

Signed-off-by: David Goulet <dgoulet@torproject.org>
---
 src/core/or/circuituse.c | 66 +++++++++++++++++++++++++++++++---------
 src/core/or/circuituse.h |  9 ++++++
 2 files changed, 61 insertions(+), 14 deletions(-)

diff --git a/src/core/or/circuituse.c b/src/core/or/circuituse.c
index a74ecbfd54..8a667024dc 100644
--- a/src/core/or/circuituse.c
+++ b/src/core/or/circuituse.c
@@ -1965,23 +1965,61 @@ have_enough_path_info(int need_exit)
 int
 circuit_purpose_is_hidden_service(uint8_t purpose)
 {
-   if (purpose == CIRCUIT_PURPOSE_HS_VANGUARDS) {
-     return 1;
-   }
+  /* HS Vanguard purpose. */
+  if (circuit_purpose_is_hs_vanguards(purpose)) {
+    return 1;
+  }
 
-   /* Client-side purpose */
-   if (purpose >= CIRCUIT_PURPOSE_C_HS_MIN_ &&
-       purpose <= CIRCUIT_PURPOSE_C_HS_MAX_) {
-     return 1;
-   }
+  /* Client-side purpose */
+  if (circuit_purpose_is_hs_client(purpose)) {
+    return 1;
+  }
 
-   /* Service-side purpose */
-   if (purpose >= CIRCUIT_PURPOSE_S_HS_MIN_ &&
-       purpose <= CIRCUIT_PURPOSE_S_HS_MAX_) {
-     return 1;
-   }
+  /* Service-side purpose */
+  if (circuit_purpose_is_hs_service(purpose)) {
+    return 1;
+  }
 
-   return 0;
+  return 0;
+}
+
+/** Retrun true iff the given circuit is an HS client circuit. */
+bool
+circuit_purpose_is_hs_client(const uint8_t purpose)
+{
+  return (purpose >= CIRCUIT_PURPOSE_C_HS_MIN_ &&
+          purpose <= CIRCUIT_PURPOSE_C_HS_MAX_);
+}
+
+/** Retrun true iff the given circuit is an HS service circuit. */
+bool
+circuit_purpose_is_hs_service(const uint8_t purpose)
+{
+  return (purpose >= CIRCUIT_PURPOSE_S_HS_MIN_ &&
+          purpose <= CIRCUIT_PURPOSE_S_HS_MAX_);
+}
+
+/** Retrun true iff the given circuit is an HS Vanguards circuit. */
+bool
+circuit_purpose_is_hs_vanguards(const uint8_t purpose)
+{
+  return (purpose == CIRCUIT_PURPOSE_HS_VANGUARDS);
+}
+
+/** Retrun true iff the given circuit is an HS v2 circuit. */
+bool
+circuit_is_hs_v2(const circuit_t *circ)
+{
+  return (CIRCUIT_IS_ORIGIN(circ) &&
+          (CONST_TO_ORIGIN_CIRCUIT(circ)->rend_data != NULL));
+}
+
+/** Retrun true iff the given circuit is an HS v3 circuit. */
+bool
+circuit_is_hs_v3(const circuit_t *circ)
+{
+  return (CIRCUIT_IS_ORIGIN(circ) &&
+          (CONST_TO_ORIGIN_CIRCUIT(circ)->hs_ident != NULL));
 }
 
 /**
diff --git a/src/core/or/circuituse.h b/src/core/or/circuituse.h
index 25588dbb11..8709d74b81 100644
--- a/src/core/or/circuituse.h
+++ b/src/core/or/circuituse.h
@@ -64,6 +64,15 @@ int hostname_in_track_host_exits(const or_options_t *options,
 void mark_circuit_unusable_for_new_conns(origin_circuit_t *circ);
 
 int circuit_purpose_is_hidden_service(uint8_t);
+
+/* Series of helper functions for hidden services. */
+bool circuit_purpose_is_hs_client(const uint8_t purpose);
+bool circuit_purpose_is_hs_service(const uint8_t purpose);
+bool circuit_purpose_is_hs_vanguards(const uint8_t purpose);
+
+bool circuit_is_hs_v2(const circuit_t *circ);
+bool circuit_is_hs_v3(const circuit_t *circ);
+
 int circuit_should_use_vanguards(uint8_t);
 void circuit_sent_valid_data(origin_circuit_t *circ, uint16_t relay_body_len);
 void circuit_read_valid_data(origin_circuit_t *circ, uint16_t relay_body_len);