protover: Support Relay=5 for Conflux (prop329)

Closes #40721

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

src/core/or/or.h

@@ -731,6 +731,9 @@ typedef struct protover_summary_flags_t {
   /** True iff this router supports congestion control.
    * Requires both FlowCtrl=2 *and* Relay=4 */
   unsigned int supports_congestion_control : 1;
+
+  /** True iff this router supports conflux. Requires Relay=5 */
+  unsigned int supports_conflux : 1;
 } protover_summary_flags_t;
 
 typedef struct routerinfo_t routerinfo_t;

src/core/or/protover.c

@@ -55,6 +55,7 @@ static const struct {
   { PRT_PADDING, "Padding"},
   { PRT_CONS, "Cons" },
   { PRT_FLOWCTRL, "FlowCtrl"},
+  { PRT_CONFLUX, "Conflux"},
 };
 
 #define N_PROTOCOL_NAMES ARRAY_LENGTH(PROTOCOL_NAMES)
@@ -386,6 +387,7 @@ protocol_list_supports_protocol_or_later(const char *list,
  * XXX START OF HAZARDOUS ZONE XXX
  */
 /* All protocol version that this relay version supports. */
+#define PR_CONFLUX_V   "1"
 #define PR_CONS_V      "1-2"
 #define PR_DESC_V      "1-2"
 #define PR_DIRCACHE_V  "2"
@@ -409,6 +411,7 @@ const char *
 protover_get_supported(const protocol_type_t type)
 {
   switch (type) {
+  case PRT_CONFLUX: return PR_CONFLUX_V;
   case PRT_CONS: return PR_CONS_V;
   case PRT_DESC: return PR_DESC_V;
   case PRT_DIRCACHE: return PR_DIRCACHE_V;
@@ -471,6 +474,7 @@ protover_get_supported_protocols(void)
    */
 
   return
+    "Conflux=" PR_CONFLUX_V " "
     "Cons=" PR_CONS_V " "
     "Desc=" PR_DESC_V " "
     "DirCache=" PR_DIRCACHE_V " "

src/core/or/protover.h

@@ -37,6 +37,8 @@ struct smartlist_t;
 #define PROTOVER_RELAY_CANONICAL_IPV6 3
 /** The protover version number where relays can accept ntorv3 */
 #define PROTOVER_RELAY_NTOR_V3 4
+/** The protover that signals conflux support. */
+#define PROTOVER_CONFLUX_V1 1
 
 /** The protover version number that signifies HSv3 intro point support */
 #define PROTOVER_HS_INTRO_V3 4
@@ -72,6 +74,7 @@ typedef enum protocol_type_t {
   PRT_CONS      = 9,
   PRT_PADDING   = 10,
   PRT_FLOWCTRL  = 11,
+  PRT_CONFLUX   = 12,
 } protocol_type_t;
 
 bool protover_list_is_invalid(const char *s);

src/core/or/versions.c

@@ -488,6 +488,13 @@ memoize_protover_summary(protover_summary_flags_t *out,
     protocol_list_supports_protocol(protocols, PRT_RELAY,
                                     PROTOVER_RELAY_NTOR_V3);
 
+  /* Conflux requires congestion control. */
+  out->supports_conflux =
+    protocol_list_supports_protocol(protocols, PRT_FLOWCTRL,
+                                    PROTOVER_FLOWCTRL_CC) &&
+    protocol_list_supports_protocol(protocols, PRT_CONFLUX,
+                                    PROTOVER_CONFLUX_V1);
+
   protover_summary_flags_t *new_cached = tor_memdup(out, sizeof(*out));
   cached = strmap_set(protover_summary_map, protocols, new_cached);
   tor_assert(!cached);

src/feature/nodelist/nodelist.c

@@ -1205,7 +1205,7 @@ node_ed25519_id_matches(const node_t *node, const ed25519_public_key_t *id)
 /** Dummy object that should be unreturnable.  Used to ensure that
  * node_get_protover_summary_flags() always returns non-NULL. */
 static const protover_summary_flags_t zero_protover_flags = {
-  0,0,0,0,0,0,0,0,0,0,0,0,0
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0
 };
 
 /** Return the protover_summary_flags for a given node. */
@@ -1341,6 +1341,15 @@ node_supports_accepting_ipv6_extends(const node_t *node,
   }
 }
 
+/** Return true iff the given node supports conflux (Relay=5) */
+bool
+node_supports_conflux(const node_t *node)
+{
+  tor_assert(node);
+
+  return node_get_protover_summary_flags(node)->supports_conflux;
+}
+
 /** Return the RSA ID key's SHA1 digest for the provided node. */
 const uint8_t *
 node_get_rsa_id_digest(const node_t *node)

src/feature/nodelist/nodelist.h

@@ -84,6 +84,7 @@ bool node_supports_establish_intro_dos_extension(const node_t *node);
 bool node_supports_initiating_ipv6_extends(const node_t *node);
 bool node_supports_accepting_ipv6_extends(const node_t *node,
                                           bool need_canonical_ipv6_conn);
+bool node_supports_conflux(const node_t *node);
 
 const uint8_t *node_get_rsa_id_digest(const node_t *node);
 MOCK_DECL(smartlist_t *,node_get_link_specifier_smartlist,(const node_t *node,