[tor-commits] [tor/master] Extract code to summarize protocol versions into new function

[nickm at torproject.org]

commit 7792be2d446a35ad71d0c67fb762f868ae07b99c
Author: Nick Mathewson <nickm at torproject.org>
Date:   Wed Jan 24 13:38:01 2018 -0500

    Extract code to summarize protocol versions into new function
    
    This will let us put this summary into routerinfo_t too.
    
    No behavior change.
---
 src/or/routerparse.c | 93 ++++++++++++++++++++++++++++++++--------------------
 1 file changed, 57 insertions(+), 36 deletions(-)

diff --git a/src/or/routerparse.c b/src/or/routerparse.c
index b8f7e166a..1cbbb1728 100644
--- a/src/or/routerparse.c
+++ b/src/or/routerparse.c
@@ -2530,6 +2530,50 @@ routerstatus_parse_guardfraction(const char *guardfraction_str,
   return 0;
 }
 
+/** Summarize the protocols listed in <b>protocols</b> into <b>out</b>,
+ * falling back or correcting them based on <b>version</b> as appropriate.
+ */
+static void
+summarize_protover_flags(protover_summary_flags_t *out,
+                         const char *protocols,
+                         const char *version)
+{
+  tor_assert(out);
+  memset(out, 0, sizeof(*out));
+  if (protocols) {
+    out->protocols_known = 1;
+    out->supports_extend2_cells =
+      protocol_list_supports_protocol(protocols, PRT_RELAY, 2);
+    out->supports_ed25519_link_handshake_compat =
+      protocol_list_supports_protocol(protocols, PRT_LINKAUTH, 3);
+    out->supports_ed25519_link_handshake_any =
+      protocol_list_supports_protocol_or_later(protocols, PRT_LINKAUTH, 3);
+    out->supports_ed25519_hs_intro =
+      protocol_list_supports_protocol(protocols, PRT_HSINTRO, 4);
+    out->supports_v3_hsdir =
+      protocol_list_supports_protocol(protocols, PRT_HSDIR,
+                                      PROTOVER_HSDIR_V3);
+    out->supports_v3_rendezvous_point =
+      protocol_list_supports_protocol(protocols, PRT_HSDIR,
+                                      PROTOVER_HS_RENDEZVOUS_POINT_V3);
+  }
+  if (version && !strcmpstart(version, "Tor ")) {
+    if (!out->protocols_known) {
+      /* The version is a "Tor" version, and where there is no
+       * list of protocol versions that we should be looking at instead. */
+
+      out->supports_extend2_cells =
+        tor_version_as_new_as(version, "0.2.4.8-alpha");
+      out->protocols_known = 1;
+    } else {
+      /* Bug #22447 forces us to filter on this version. */
+      if (!tor_version_as_new_as(version, "0.3.0.8")) {
+        out->supports_v3_hsdir = 0;
+      }
+    }
+  }
+}
+
 /** Given a string at *<b>s</b>, containing a routerstatus object, and an
  * empty smartlist at <b>tokens</b>, parse and return the first router status
  * object in the string, and advance *<b>s</b> to just after the end of the
@@ -2695,44 +2739,21 @@ routerstatus_parse_entry_from_string(memarea_t *area,
     if (consensus_method >= MIN_METHOD_FOR_EXCLUDING_INVALID_NODES)
       rs->is_valid = 1;
   }
-  int found_protocol_list = 0;
-  if ((tok = find_opt_by_keyword(tokens, K_PROTO))) {
-    found_protocol_list = 1;
-    rs->pv.protocols_known = 1;
-    rs->pv.supports_extend2_cells =
-      protocol_list_supports_protocol(tok->args[0], PRT_RELAY, 2);
-    rs->pv.supports_ed25519_link_handshake_compat =
-      protocol_list_supports_protocol(tok->args[0], PRT_LINKAUTH, 3);
-    rs->pv.supports_ed25519_link_handshake_any =
-      protocol_list_supports_protocol_or_later(tok->args[0], PRT_LINKAUTH, 3);
-    rs->pv.supports_ed25519_hs_intro =
-      protocol_list_supports_protocol(tok->args[0], PRT_HSINTRO, 4);
-    rs->pv.supports_v3_hsdir =
-      protocol_list_supports_protocol(tok->args[0], PRT_HSDIR,
-                                      PROTOVER_HSDIR_V3);
-    rs->pv.supports_v3_rendezvous_point =
-      protocol_list_supports_protocol(tok->args[0], PRT_HSDIR,
-                                      PROTOVER_HS_RENDEZVOUS_POINT_V3);
-  }
-  if ((tok = find_opt_by_keyword(tokens, K_V))) {
-    tor_assert(tok->n_args == 1);
-    if (!strcmpstart(tok->args[0], "Tor ") && !found_protocol_list) {
-      /* We only do version checks like this in the case where
-       * the version is a "Tor" version, and where there is no
-       * list of protocol versions that we should be looking at instead. */
-      rs->pv.supports_extend2_cells =
-        tor_version_as_new_as(tok->args[0], "0.2.4.8-alpha");
-      rs->pv.protocols_known = 1;
-    }
-    if (!strcmpstart(tok->args[0], "Tor ") && found_protocol_list) {
-      /* Bug #22447 forces us to filter on this version. */
-      if (!tor_version_as_new_as(tok->args[0], "0.3.0.8")) {
-        rs->pv.supports_v3_hsdir = 0;
+  {
+    const char *protocols = NULL, *version = NULL;
+    if ((tok = find_opt_by_keyword(tokens, K_PROTO))) {
+      tor_assert(tok->n_args == 1);
+      protocols = tok->args[0];
+    }
+    if ((tok = find_opt_by_keyword(tokens, K_V))) {
+      tor_assert(tok->n_args == 1);
+      version = tok->args[0];
+      if (vote_rs) {
+        vote_rs->version = tor_strdup(tok->args[0]);
       }
     }
-    if (vote_rs) {
-      vote_rs->version = tor_strdup(tok->args[0]);
-    }
+
+    summarize_protover_flags(&rs->pv, protocols, version);
   }
 
   /* handle weighting/bandwidth info */