control.c

关于tor匿名通信的源代码

  } else if (!strcmp(question, "desc/all-recent")) {
    routerlist_t *routerlist = router_get_routerlist();
    smartlist_t *sl = smartlist_create();
    if (routerlist && routerlist->routers) {
      SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, ri,
      {
        const char *body = signed_descriptor_get_body(&ri->cache_info);
        if (body)
          smartlist_add(sl,
                  tor_strndup(body, ri->cache_info.signed_descriptor_len));
      });
    }
    *answer = smartlist_join_strings(sl, "", 0, NULL);
    SMARTLIST_FOREACH(sl, char *, c, tor_free(c));
    smartlist_free(sl);
  } else if (!strcmp(question, "desc/all-recent-extrainfo-hack")) {
    /* XXXX Remove this once Torstat asks for extrainfos. */
    routerlist_t *routerlist = router_get_routerlist();
    smartlist_t *sl = smartlist_create();
    if (routerlist && routerlist->routers) {
      SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, ri,
      {
        const char *body = signed_descriptor_get_body(&ri->cache_info);
        signed_descriptor_t *ei = extrainfo_get_by_descriptor_digest(
                                     ri->cache_info.extra_info_digest);
        if (ei && body) {
          smartlist_add(sl, munge_extrainfo_into_routerinfo(body,
                                                        &ri->cache_info, ei));
        } else if (body) {
          smartlist_add(sl,
                  tor_strndup(body, ri->cache_info.signed_descriptor_len));
        }
      });
    }
    *answer = smartlist_join_strings(sl, "", 0, NULL);
    SMARTLIST_FOREACH(sl, char *, c, tor_free(c));
    smartlist_free(sl);
  } else if (!strcmpstart(question, "desc-annotations/id/")) {
    routerinfo_t *ri = router_get_by_hexdigest(question+
                                               strlen("desc-annotations/id/"));
    if (ri) {
      const char *annotations =
        signed_descriptor_get_annotations(&ri->cache_info);
      if (annotations)
        *answer = tor_strndup(annotations,
                              ri->cache_info.annotations_len);
    }
  } else if (!strcmpstart(question, "dir/server/")) {
    size_t answer_len = 0, url_len = strlen(question)+2;
    char *url = tor_malloc(url_len);
    smartlist_t *descs = smartlist_create();
    const char *msg;
    int res;
    char *cp;
    tor_snprintf(url, url_len, "/tor/%s", question+4);
    res = dirserv_get_routerdescs(descs, url, &msg);
    if (res) {
      log_warn(LD_CONTROL, "getinfo '%s': %s", question, msg);
      smartlist_free(descs);
      return -1;
    }
    SMARTLIST_FOREACH(descs, signed_descriptor_t *, sd,
                      answer_len += sd->signed_descriptor_len);
    cp = *answer = tor_malloc(answer_len+1);
    SMARTLIST_FOREACH(descs, signed_descriptor_t *, sd,
                      {
                        memcpy(cp, signed_descriptor_get_body(sd),
                               sd->signed_descriptor_len);
                        cp += sd->signed_descriptor_len;
                      });
    *cp = '\0';
    tor_free(url);
    smartlist_free(descs);
  } else if (!strcmpstart(question, "dir/status/")) {
    if (directory_permits_controller_requests(get_options())) {
      size_t len=0;
      char *cp;
      smartlist_t *status_list = smartlist_create();
      dirserv_get_networkstatus_v2(status_list,
                                   question+strlen("dir/status/"));
      SMARTLIST_FOREACH(status_list, cached_dir_t *, d, len += d->dir_len);
      cp = *answer = tor_malloc(len+1);
      SMARTLIST_FOREACH(status_list, cached_dir_t *, d, {
          memcpy(cp, d->dir, d->dir_len);
          cp += d->dir_len;
        });
      *cp = '\0';
      smartlist_free(status_list);
    } else {
      smartlist_t *fp_list = smartlist_create();
      smartlist_t *status_list = smartlist_create();
      dirserv_get_networkstatus_v2_fingerprints(
                             fp_list, question+strlen("dir/status/"));
      SMARTLIST_FOREACH(fp_list, const char *, fp, {
          char *s;
          char *fname = networkstatus_get_cache_filename(fp);
          s = read_file_to_str(fname, 0, NULL);
          if (s)
            smartlist_add(status_list, s);
          tor_free(fname);
        });
      SMARTLIST_FOREACH(fp_list, char *, fp, tor_free(fp));
      smartlist_free(fp_list);
      *answer = smartlist_join_strings(status_list, "", 0, NULL);
      SMARTLIST_FOREACH(status_list, char *, s, tor_free(s));
      smartlist_free(status_list);
    }
  } else if (!strcmp(question, "network-status")) {
    routerlist_t *routerlist = router_get_routerlist();
    int verbose = control_conn->use_long_names;
    if (!routerlist || !routerlist->routers ||
        list_server_status_v1(routerlist->routers, answer,
                              verbose ? 2 : 1) < 0) {
      return -1;
    }
  } else if (!strcmpstart(question, "extra-info/digest/")) {
    question += strlen("extra-info/digest/");
    if (strlen(question) == HEX_DIGEST_LEN) {
      char d[DIGEST_LEN];
      signed_descriptor_t *sd = NULL;
      if (base16_decode(d, sizeof(d), question, strlen(question))==0) {
        /* XXXX this test should move into extrainfo_get_by_descriptor_digest,
         * but I don't want to risk affecting other parts of the code,
         * especially since the rules for using our own extrainfo (including
         * when it might be freed) are different from those for using one
         * we have downloaded. */
        if (router_extrainfo_digest_is_me(d))
          sd = &(router_get_my_extrainfo()->cache_info);
        else
          sd = extrainfo_get_by_descriptor_digest(d);
      }
      if (sd) {
        const char *body = signed_descriptor_get_body(sd);
        if (body)
          *answer = tor_strndup(body, sd->signed_descriptor_len);
      }
    }
  }

  return 0;
}

/** Implementation helper for GETINFO: knows how to generate summaries of the
 * current states of things we send events about. */
static int
getinfo_helper_events(control_connection_t *control_conn,
                      const char *question, char **answer)
{
  if (!strcmp(question, "circuit-status")) {
    circuit_t *circ;
    smartlist_t *status = smartlist_create();
    for (circ = _circuit_get_global_list(); circ; circ = circ->next) {
      char *s, *path;
      size_t slen;
      const char *state;
      if (! CIRCUIT_IS_ORIGIN(circ) || circ->marked_for_close)
        continue;
      if (control_conn->use_long_names)
        path = circuit_list_path_for_controller(TO_ORIGIN_CIRCUIT(circ));
      else
        path = circuit_list_path(TO_ORIGIN_CIRCUIT(circ),0);
      if (circ->state == CIRCUIT_STATE_OPEN)
        state = "BUILT";
      else if (strlen(path))
        state = "EXTENDED";
      else
        state = "LAUNCHED";

      slen = strlen(path)+strlen(state)+20;
      s = tor_malloc(slen+1);
      tor_snprintf(s, slen, "%lu %s%s%s",
                   (unsigned long)TO_ORIGIN_CIRCUIT(circ)->global_identifier,
                   state, *path ? " " : "", path);
      smartlist_add(status, s);
      tor_free(path);
    }
    *answer = smartlist_join_strings(status, "\r\n", 0, NULL);
    SMARTLIST_FOREACH(status, char *, cp, tor_free(cp));
    smartlist_free(status);
  } else if (!strcmp(question, "stream-status")) {
    smartlist_t *conns = get_connection_array();
    smartlist_t *status = smartlist_create();
    char buf[256];
    SMARTLIST_FOREACH(conns, connection_t *, base_conn,
    {
      const char *state;
      edge_connection_t *conn;
      char *s;
      size_t slen;
      circuit_t *circ;
      origin_circuit_t *origin_circ = NULL;
      if (base_conn->type != CONN_TYPE_AP ||
          base_conn->marked_for_close ||
          base_conn->state == AP_CONN_STATE_SOCKS_WAIT ||
          base_conn->state == AP_CONN_STATE_NATD_WAIT)
        continue;
      conn = TO_EDGE_CONN(base_conn);
      switch (conn->_base.state)
        {
        case AP_CONN_STATE_CONTROLLER_WAIT:
        case AP_CONN_STATE_CIRCUIT_WAIT:
          if (conn->socks_request &&
              SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command))
            state = "NEWRESOLVE";
          else
            state = "NEW";
          break;
        case AP_CONN_STATE_RENDDESC_WAIT:
        case AP_CONN_STATE_CONNECT_WAIT:
          state = "SENTCONNECT"; break;
        case AP_CONN_STATE_RESOLVE_WAIT:
          state = "SENTRESOLVE"; break;
        case AP_CONN_STATE_OPEN:
          state = "SUCCEEDED"; break;
        default:
          log_warn(LD_BUG, "Asked for stream in unknown state %d",
                   conn->_base.state);
          continue;
        }
      circ = circuit_get_by_edge_conn(conn);
      if (circ && CIRCUIT_IS_ORIGIN(circ))
        origin_circ = TO_ORIGIN_CIRCUIT(circ);
      write_stream_target_to_buf(conn, buf, sizeof(buf));
      slen = strlen(buf)+strlen(state)+32;
      s = tor_malloc(slen+1);
      tor_snprintf(s, slen, "%lu %s %lu %s",
                   (unsigned long) conn->global_identifier,state,
                   origin_circ?
                         (unsigned long)origin_circ->global_identifier : 0ul,
                   buf);
      smartlist_add(status, s);
    });
    *answer = smartlist_join_strings(status, "\r\n", 0, NULL);
    SMARTLIST_FOREACH(status, char *, cp, tor_free(cp));
    smartlist_free(status);
  } else if (!strcmp(question, "orconn-status")) {
    smartlist_t *conns = get_connection_array();
    smartlist_t *status = smartlist_create();
    SMARTLIST_FOREACH(conns, connection_t *, base_conn,
    {
      const char *state;
      char *s;
      char name[128];
      size_t slen;
      or_connection_t *conn;
      if (base_conn->type != CONN_TYPE_OR || base_conn->marked_for_close)
        continue;
      conn = TO_OR_CONN(base_conn);
      if (conn->_base.state == OR_CONN_STATE_OPEN)
        state = "CONNECTED";
      else if (conn->nickname)
        state = "LAUNCHED";
      else
        state = "NEW";
      orconn_target_get_name(control_conn->use_long_names, name, sizeof(name),
                             conn);
      slen = strlen(name)+strlen(state)+2;
      s = tor_malloc(slen+1);
      tor_snprintf(s, slen, "%s %s", name, state);
      smartlist_add(status, s);
    });
    *answer = smartlist_join_strings(status, "\r\n", 0, NULL);
    SMARTLIST_FOREACH(status, char *, cp, tor_free(cp));
    smartlist_free(status);
  } else if (!strcmpstart(question, "addr-mappings/") ||
             !strcmpstart(question, "address-mappings/")) {
    /* XXXX021 Warn about deprecated addr-mappings variant. */
    time_t min_e, max_e;
    smartlist_t *mappings;
    int want_expiry = !strcmpstart(question, "address-mappings/");
    question += strlen(want_expiry ? "address-mappings/"
                                   : "addr-mappings/");
    if (!strcmp(question, "all")) {
      min_e = 0; max_e = TIME_MAX;
    } else if (!strcmp(question, "cache")) {
      min_e = 2; max_e = TIME_MAX;
    } else if (!strcmp(question, "config")) {
      min_e = 0; max_e = 0;
    } else if (!strcmp(question, "control")) {
      min_e = 1; max_e = 1;
    } else {
      return 0;
    }
    mappings = smartlist_create();
    addressmap_get_mappings(mappings, min_e, max_e, want_expiry);
    *answer = smartlist_join_strings(mappings, "\r\n", 0, NULL);
    SMARTLIST_FOREACH(mappings, char *, cp, tor_free(cp));
    smartlist_free(mappings);
  } else if (!strcmpstart(question, "status/")) {
    /* Note that status/ is not a catch-all for events; there's only supposed
     * to be a status GETINFO if there's a corresponding STATUS event. */
    if (!strcmp(question, "status/circuit-established")) {
      *answer = tor_strdup(has_completed_circuit ? "1" : "0");
    } else if (!strcmp(question, "status/enough-dir-info")) {
      *answer = tor_strdup(router_have_minimum_dir_info() ? "1" : "0");
    } else if (!strcmp(question, "status/good-server-descriptor")) {
      *answer = tor_strdup(directories_have_accepted_server_descriptor()
                           ? "1" : "0");
    } else if (!strcmp(question, "status/reachability-succeeded/or")) {
      *answer = tor_strdup(check_whether_orport_reachable() ? "1" : "0");
    } else if (!strcmp(question, "status/reachability-succeeded/dir")) {
      *answer = tor_strdup(check_whether_dirport_reachable() ? "1" : "0");
    } else if (!strcmp(question, "status/reachability-succeeded")) {
      *answer = tor_malloc(16);
      tor_snprintf(*answer, 16, "OR=%d DIR=%d",
                   check_whether_orport_reachable() ? 1 : 0,
                   check_whether_dirport_reachable() ? 1 : 0);
    } else if (!strcmpstart(question, "status/version/")) {
      int is_server = server_mode(get_options());
      networkstatus_t *c = networkstatus_get_latest_consensus();
      version_status_t status;
      const char *recommended;
      if (c) {
        recommended = is_server ? c->server_versions : c->client_versions;
        status = tor_version_is_obsolete(VERSION, recommended);
      } else {
        recommended = "?";
        status = VS_UNKNOWN;
      }

      if (!strcmp(question, "status/version/recommended")) {
        *answer = tor_strdup(recommended);
        return 0;
      }
      if (!strcmp(question, "status/version/current")) {
        switch (status)
          {
          case VS_RECOMMENDED: *answer = tor_strdup("recommended"); break;
          case VS_OLD: *answer = tor_strdup("obsolete"); break;
          case VS_NEW: *answer = tor_strdup("new"); break;
          case VS_NEW_IN_SERIES: *answer = tor_strdup("new in series"); break;
          case VS_UNRECOMMENDED: *answer = tor_strdup("unrecommended"); break;
          case VS_EMPTY: *answer = tor_strdup("none recommended"); break;
          case VS_UNKNOWN: *answer = tor_strdup("unknown"); break;
          default: tor_fragile_assert();
          }
      } else if (!strcmp(question, "status/version/num-versioning") ||
                 !strcmp(question, "status/version/num-concurring")) {
        char s[33];
        tor_snprintf(s, sizeof(s), "%d", get_n_authorities(V3_AUTHORITY));
        *answer = tor_strdup(s);
        log_warn(LD_GENERAL, "%s is deprecated; it no longer gives useful "
                 "information", question);
      }
    } else {
      return 0;
    }
  }
  return 0;
}

/** Callback function for GETINFO: on a given control connection, try to
 * answer the question <b>q</b> and store the newly-allocated answer in
 * *<b>a</b>.  If there's no answer, or an error occurs, just don't set
 * <b>a</b>.  Return 0.
 */
typedef int (*getinfo_helper_t)(control_connection_t *,
                                const char *q, char **a);

/** A single item for the GETINFO question-to-answer-function table. */
typedef struct getinfo_item_t {
  const char *varname; /**< The value (or prefix) of the question. */
  getinfo_helper_t fn; /**< The function that knows the answer: