Commit b3178134 authored by Nick Mathewson's avatar Nick Mathewson 🥔
Browse files

Make GETINFO entry-guards work again with prop271 

This is not a great solution, but it's as close to
backward-compatible as possible.  A better GETINFO API should expose
more information.
parent ded98be4

src/or/entrynodes.c

+90 −41
Original line number Diff line number Diff line
@@ -4746,46 +4746,22 @@ entry_guards_update_state(or_state_t *state) 
  entry_guards_dirty = 0;

}



/** If <b>question</b> is the string "entry-guards", then dump

 * to *<b>answer</b> a newly allocated string describing all of

 * the nodes in the global entry_guards list. See control-spec.txt

 * for details.

 * For backward compatibility, we also handle the string "helper-nodes".

 *

 * XXX this should be totally redesigned after prop 271 too, and that's

 * going to take some control spec work.

 * */

int

getinfo_helper_entry_guards(control_connection_t *conn,

                            const char *question, char **answer,

                            const char **errmsg)

/**

 * Format a single entry guard in the format expected by the controller.

 * Return a newly allocated string.

 */

STATIC char *

getinfo_helper_format_single_entry_guard(const entry_guard_t *e,

                                         int legacy_guard)

{

  guard_selection_t *gs = get_guard_selection_info();



  tor_assert(gs != NULL);

#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

  tor_assert(gs->chosen_entry_guards != NULL);

#else

  // XXXX

  (void)question;

  (void)answer;

#endif



  (void) conn;

  (void) errmsg;



#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

  if (!strcmp(question,"entry-guards") ||

      !strcmp(question,"helper-nodes")) {

    smartlist_t *sl = smartlist_new();

    char tbuf[ISO_TIME_LEN+1];

    char nbuf[MAX_VERBOSE_NICKNAME_LEN+1];



    SMARTLIST_FOREACH_BEGIN(gs->chosen_entry_guards, entry_guard_t *, e) {

  const char *status = NULL;

  time_t when = 0;

  const node_t *node;

  char tbuf[ISO_TIME_LEN+1];

  char nbuf[MAX_VERBOSE_NICKNAME_LEN+1];



  if (legacy_guard) {

#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

    if (!e->made_contact) {

      status = "never-connected";

    } else if (e->bad_since) {
@@ -4797,8 +4773,32 @@ getinfo_helper_entry_guards(control_connection_t *conn, 
    } else {

      status = "up";

    }

#else

    tor_assert_nonfatal_unreached();

    status = "BUG";

#endif

  } else {

    /* modern case.  This is going to be a bit tricky, since the status

     * codes above weren't really intended for prop271 guards.

     *

     * XXXX use a more appropriate format for exporting this information

     */

    if (e->confirmed_idx < 0) {

      status = "never-connected";

    } else if (! e->currently_listed) {

      when = e->unlisted_since_date;

      status = "unusable";

    } else if (! e->is_filtered_guard) {

      status = "unusable";

    } else if (e->is_reachable == GUARD_REACHABLE_NO) {

      when = e->failing_since;

      status = "down";

    } else {

      status = "up";

    }

  }



        node = node_get_by_id(e->identity);

  node = entry_guard_find_node(e);

  if (node) {

    node_get_verbose_nickname(node, nbuf);

  } else {
@@ -4808,18 +4808,67 @@ getinfo_helper_entry_guards(control_connection_t *conn, 
     * this router any longer; don't include it. */

  }



  char *result = NULL;

  if (when) {

    format_iso_time(tbuf, when);

          smartlist_add_asprintf(sl, "%s %s %s\n", nbuf, status, tbuf);

    tor_asprintf(&result, "%s %s %s\n", nbuf, status, tbuf);

  } else {

    tor_asprintf(&result, "%s %s\n", nbuf, status);

  }

  return result;

}



/** If <b>question</b> is the string "entry-guards", then dump

 * to *<b>answer</b> a newly allocated string describing all of

 * the nodes in the global entry_guards list. See control-spec.txt

 * for details.

 * For backward compatibility, we also handle the string "helper-nodes".

 *

 * XXX this should be totally redesigned after prop 271 too, and that's

 * going to take some control spec work.

 * */

int

getinfo_helper_entry_guards(control_connection_t *conn,

                            const char *question, char **answer,

                            const char **errmsg)

{

  guard_selection_t *gs = get_guard_selection_info();



  tor_assert(gs != NULL);

#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

  tor_assert(gs->chosen_entry_guards != NULL);

#endif



  (void) conn;

  (void) errmsg;



  if (!strcmp(question,"entry-guards") ||

      !strcmp(question,"helper-nodes")) {

    const smartlist_t *guards;

    int legacy_mode;

    if (gs->type == GS_TYPE_LEGACY) {

#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

      guards = gs->chosen_entry_guards;

      legacy_mode = 1;

#else

      tor_assert_nonfatal_unreached();

      return 0;

#endif

    } else {

          smartlist_add_asprintf(sl, "%s %s\n", nbuf, status);

      guards = gs->sampled_entry_guards;

      legacy_mode = 0;

    }



    smartlist_t *sl = smartlist_new();



    SMARTLIST_FOREACH_BEGIN(guards, const entry_guard_t *, e) {

      char *cp = getinfo_helper_format_single_entry_guard(e, legacy_mode);

      smartlist_add(sl, cp);

    } SMARTLIST_FOREACH_END(e);

    *answer = smartlist_join_strings(sl, "", 0, NULL);

    SMARTLIST_FOREACH(sl, char *, c, tor_free(c));

    smartlist_free(sl);

  }

#endif

  return 0;

}

src/or/entrynodes.h

+2 −1
Original line number Diff line number Diff line
@@ -610,7 +610,8 @@ STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs, 
                                                entry_guard_t *guard,

                                                unsigned old_state);

STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b);



STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e,

                                                      int is_legacy);

#ifdef ENABLE_LEGACY_GUARD_ALGORITHM

// ---------- XXXX this stuff is pre-prop271.