Add host name resolution information to pg_hba.conf error messages

This is to be able to analyze issues with host names in pg_hba.conf.

diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index d1538809f85c4b4b48367e5c29355529c729d49b..1b6399d91da577bd32405b46b28e95aa799c2a10 100644 (file)
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -439,6 +439,17 @@ ClientAuthentication(Port *port)
                                   NULL, 0,
                                   NI_NUMERICHOST);
 
+#define HOSTNAME_LOOKUP_DETAIL(port) \
+               (port->remote_hostname                \
+                ? (port->remote_hostname_resolv == +1                  \
+                   ? errdetail_log("Client IP address resolved to \"%s\", forward lookup matches.", port->remote_hostname) \
+                   : (port->remote_hostname_resolv == 0                \
+                      ? errdetail_log("Client IP address resolved to \"%s\", forward lookup not checked.", port->remote_hostname) \
+                      : (port->remote_hostname_resolv == -1            \
+                         ? errdetail_log("Client IP address resolved to \"%s\", forward lookup does not match.", port->remote_hostname) \
+                         : 0)))                                        \
+                : 0)
+
                if (am_walsender)
                {
 #ifdef USE_SSL
@@ -446,12 +457,14 @@ ClientAuthentication(Port *port)
                       (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
                        errmsg("no pg_hba.conf entry for replication connection from host \"%s\", user \"%s\", %s",
                               hostinfo, port->user_name,
-                              port->ssl ? _("SSL on") : _("SSL off"))));
+                              port->ssl ? _("SSL on") : _("SSL off")),
+                       HOSTNAME_LOOKUP_DETAIL(port)));
 #else
                    ereport(FATAL,
                       (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
                        errmsg("no pg_hba.conf entry for replication connection from host \"%s\", user \"%s\"",
-                              hostinfo, port->user_name)));
+                              hostinfo, port->user_name),
+                       HOSTNAME_LOOKUP_DETAIL(port)));
 #endif
                }
                else
@@ -462,13 +475,15 @@ ClientAuthentication(Port *port)
                        errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\", %s",
                               hostinfo, port->user_name,
                               port->database_name,
-                              port->ssl ? _("SSL on") : _("SSL off"))));
+                              port->ssl ? _("SSL on") : _("SSL off")),
+                       HOSTNAME_LOOKUP_DETAIL(port)));
 #else
                    ereport(FATAL,
                       (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
                        errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\"",
                               hostinfo, port->user_name,
-                              port->database_name)));
+                              port->database_name),
+                       HOSTNAME_LOOKUP_DETAIL(port)));
 #endif
                }
                break;