Downgrade IP version warnings to avoid filling logs

Downgrade logs and backtraces about IP versions to
info-level. Only log backtraces once each time tor runs.

Assists in diagnosing bug 18351; bugfix on c3cc8e16e in
tor-0.2.8.1-alpha.

Reported by "sysrqb" and "Christian", patch by "teor".

3 files changed, 28 insertions, 10 deletions

diff --git a/src/or/connection.c b/src/or/connection.c
index 4e915f1213..fc9ec13c41 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -1793,11 +1793,15 @@ connection_connect_log_client_use_ip_version(const connection_t *conn)
   /* Check if we broke a mandatory address family restriction */
   if ((must_ipv4 && tor_addr_family(&real_addr) == AF_INET6)
       || (must_ipv6 && tor_addr_family(&real_addr) == AF_INET)) {
-    log_warn(LD_BUG, "%s connection to %s violated ClientUseIPv%s 0.",
+    static int logged_backtrace = 0;
+    log_info(LD_BUG, "%s connection to %s violated ClientUseIPv%s 0.",
              conn->type == CONN_TYPE_OR ? "OR" : "Dir",
              fmt_addr(&real_addr),
              options->ClientUseIPv4 == 0 ? "4" : "6");
-    log_backtrace(LOG_WARN, LD_BUG, "Address came from");
+    if (!logged_backtrace) {
+      log_backtrace(LOG_INFO, LD_BUG, "Address came from");
+      logged_backtrace = 1;
+    }
   }
 
   /* Bridges are allowed to break IPv4/IPv6 ORPort preferences to connect to
diff --git a/src/or/directory.c b/src/or/directory.c
index e4feda44fc..c95944b6f2 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -674,13 +674,17 @@ directory_choose_address_routerstatus(const routerstatus_t *status,
 
   /* We rejected both addresses. This isn't great. */
   if (!have_or && !have_dir) {
-    log_warn(LD_BUG, "Rejected all OR and Dir addresses from %s when "
+    static int logged_backtrace = 0;
+    log_info(LD_BUG, "Rejected all OR and Dir addresses from %s when "
              "launching a directory connection to: IPv4 %s OR %d Dir %d "
              "IPv6 %s OR %d Dir %d", routerstatus_describe(status),
              fmt_addr32(status->addr), status->or_port,
              status->dir_port, fmt_addr(&status->ipv6_addr),
              status->ipv6_orport, status->dir_port);
-    log_backtrace(LOG_WARN, LD_BUG, "Addresses came from");
+    if (!logged_backtrace) {
+      log_backtrace(LOG_INFO, LD_BUG, "Addresses came from");
+      logged_backtrace = 1;
+    }
     return -1;
   }
 
@@ -1100,14 +1104,21 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port,
 
   if (or_connection && (!or_addr_port->port
                         || tor_addr_is_null(&or_addr_port->addr))) {
+    static int logged_backtrace = 0;
     log_warn(LD_DIR, "Cannot make an OR connection without an OR port.");
-    log_backtrace(LOG_WARN, LD_BUG, "Address came from");
+    if (!logged_backtrace) {
+      log_backtrace(LOG_INFO, LD_BUG, "Address came from");
+      logged_backtrace = 1;
+    }
     return;
   } else if (!or_connection && (!dir_addr_port->port
                                 || tor_addr_is_null(&dir_addr_port->addr))) {
+    static int logged_backtrace = 0;
     log_warn(LD_DIR, "Cannot make a Dir connection without a Dir port.");
-    log_backtrace(LOG_WARN, LD_BUG, "Address came from");
-
+    if (!logged_backtrace) {
+      log_backtrace(LOG_INFO, LD_BUG, "Address came from");
+      logged_backtrace = 1;
+    }
     return;
   }
 
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index bc5e2e9133..f065c3c202 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -1560,9 +1560,13 @@ router_picked_poor_directory_log(const routerstatus_t *rs)
   /* We couldn't find a node, or the one we have doesn't fit our preferences.
    * This might be a bug. */
   if (!rs) {
-    log_warn(LD_BUG, "Firewall denied all OR and Dir addresses for all relays "
+    static int logged_backtrace = 0;
+    log_info(LD_BUG, "Firewall denied all OR and Dir addresses for all relays "
              "when searching for a directory.");
-    log_backtrace(LOG_WARN, LD_BUG, "Node search initiated by");
+    if (!logged_backtrace) {
+      log_backtrace(LOG_INFO, LD_BUG, "Node search initiated by");
+      logged_backtrace = 1;
+    }
   } else if (!fascist_firewall_allows_rs(rs, FIREWALL_OR_CONNECTION, 1)
              && !fascist_firewall_allows_rs(rs, FIREWALL_DIR_CONNECTION, 1)
              ) {
@@ -1573,7 +1577,6 @@ router_picked_poor_directory_log(const routerstatus_t *rs)
              fmt_addr32(rs->addr), rs->or_port,
              rs->dir_port, fmt_addr(&rs->ipv6_addr),
              rs->ipv6_orport, rs->dir_port);
-    log_backtrace(LOG_INFO, LD_BUG, "Node search initiated by");
   }
 }