Line data    Source code

       1              : /* -------------------------------------------------------------------------
       2              :  *
       3              :  * auth_delay.c
       4              :  *
       5              :  * Copyright (c) 2010-2026, PostgreSQL Global Development Group
       6              :  *
       7              :  * IDENTIFICATION
       8              :  *      contrib/auth_delay/auth_delay.c
       9              :  *
      10              :  * -------------------------------------------------------------------------
      11              :  */
      12              : #include "postgres.h"
      13              : 
      14              : #include <limits.h>
      15              : 
      16              : #include "libpq/auth.h"
      17              : #include "utils/guc.h"
      18              : 
      19            0 : PG_MODULE_MAGIC_EXT(
      20              :                     .name = "auth_delay",
      21              :                     .version = PG_VERSION
      22              : );
      23              : 
      24              : /* GUC Variables */
      25              : static int  auth_delay_milliseconds = 0;
      26              : 
      27              : /* Original Hook */
      28              : static ClientAuthentication_hook_type original_client_auth_hook = NULL;
      29              : 
      30              : /*
      31              :  * Check authentication
      32              :  */
      33              : static void
      34            0 : auth_delay_checks(Port *port, int status)
      35              : {
      36              :     /*
      37              :      * Any other plugins which use ClientAuthentication_hook.
      38              :      */
      39            0 :     if (original_client_auth_hook)
      40            0 :         original_client_auth_hook(port, status);
      41              : 
      42              :     /*
      43              :      * Inject a short delay if authentication failed.
      44              :      */
      45            0 :     if (status != STATUS_OK)
      46              :     {
      47            0 :         pg_usleep(1000L * auth_delay_milliseconds);
      48              :     }
      49            0 : }
      50              : 
      51              : /*
      52              :  * Module Load Callback
      53              :  */
      54              : void
      55            0 : _PG_init(void)
      56              : {
      57              :     /* Define custom GUC variables */
      58            0 :     DefineCustomIntVariable("auth_delay.milliseconds",
      59              :                             "Milliseconds to delay before reporting authentication failure",
      60              :                             NULL,
      61              :                             &auth_delay_milliseconds,
      62              :                             0,
      63              :                             0, INT_MAX / 1000,
      64              :                             PGC_SIGHUP,
      65              :                             GUC_UNIT_MS,
      66              :                             NULL,
      67              :                             NULL,
      68              :                             NULL);
      69              : 
      70            0 :     MarkGUCPrefixReserved("auth_delay");
      71              : 
      72              :     /* Install Hooks */
      73            0 :     original_client_auth_hook = ClientAuthentication_hook;
      74            0 :     ClientAuthentication_hook = auth_delay_checks;
      75            0 : }