/*
**   PostgreSQL Password Checking Medusa Module
**
**   ------------------------------------------------------------------------
**    Copyright (C) 2009 Joe Mondloch
**    JoMo-Kun / jmk@foofus.net
**
**    This program is free software; you can redistribute it and/or modify
**    it under the terms of the GNU General Public License version 2,
**    as published by the Free Software Foundation
**
**    This program is distributed in the hope that it will be useful,
**    but WITHOUT ANY WARRANTY; without even the implied warranty of
**    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**    GNU General Public License for more details.
**
**    http://www.gnu.org/licenses/gpl.txt
**
**    This program is released under the GPL with the additional exemption
**    that compiling, linking, and/or using OpenSSL is allowed.
**
**   ------------------------------------------------------------------------
**
**
*/

#include <sys/types.h>
#include <libgen.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "module.h"

#define MODULE_NAME    "postgres.mod"
#define MODULE_AUTHOR  "JoMo-Kun <jmk@foofus.net>"
#define MODULE_SUMMARY_USAGE  "Brute force module for PostgreSQL sessions"
#define MODULE_VERSION    "2.0"
#define MODULE_VERSION_SVN "$Id: postgres.c 9217 2015-05-07 18:07:03Z jmk $"
#define MODULE_SUMMARY_FORMAT  "%s : version %s"
#define MODULE_SUMMARY_FORMAT_WARN  "%s : version %s (%s)"
#define LIBPQ_WARNING "No usable LIBPQ. Module disabled."

#ifdef HAVE_LIBPQ

#include "libpq-fe.h"

#define PORT_POSTGRESQL 5432

typedef struct __POSTGRESQL_DATA {
  char *szDB;
} _POSTGRESQL_DATA;


// Tells us whether we are to continue processing or not
enum MODULE_STATE
{
  MSTATE_NEW,
  MSTATE_RUNNING,
  MSTATE_EXITING,
  MSTATE_COMPLETE
};

// Forward declarations
int tryLogin(sLogin** login, _POSTGRESQL_DATA* _psSessionData, char* szLogin, char* szPassword);
int initModule(sLogin* login, _POSTGRESQL_DATA *_psSessionData);

// Tell medusa how many parameters this module allows
int getParamNumber()
{
  return 0;    // we don't need no stinking parameters
}

// Displays information about the module and how it must be used
void summaryUsage(char **ppszSummary)
{
  // Memory for ppszSummary will be allocated here - caller is responsible for freeing it
  int  iLength = 0;

  if (*ppszSummary == NULL)
  {
    iLength = strlen(MODULE_SUMMARY_USAGE) + strlen(MODULE_VERSION) + strlen(MODULE_SUMMARY_FORMAT) + 1;
    *ppszSummary = (char*)malloc(iLength);
    memset(*ppszSummary, 0, iLength);
    snprintf(*ppszSummary, iLength, MODULE_SUMMARY_FORMAT, MODULE_SUMMARY_USAGE, MODULE_VERSION);
  } 
  else 
  {
    writeError(ERR_ERROR, "%s reports an error in summaryUsage() : ppszSummary must be NULL when called", MODULE_NAME);
  }
}

/* Display module usage information */
void showUsage()
{
  writeVerbose(VB_NONE, "%s (%s) %s :: %s\n", MODULE_NAME, MODULE_VERSION, MODULE_AUTHOR, MODULE_SUMMARY_USAGE);
  writeVerbose(VB_NONE, "Available module options:");
  writeVerbose(VB_NONE, "  DB:? ");
  writeVerbose(VB_NONE, "    Sets target database name.");
  writeVerbose(VB_NONE, "");
  writeVerbose(VB_NONE, "  Usage example: \"-M postgres -m DB:some_db\"");
  writeVerbose(VB_NONE, "");
}

// The "main" of the medusa module world - this is what gets called to actually do the work
int go(sLogin* logins, int argc, char *argv[])
{
  int i;
  char *strtok_ptr, *pOpt, *pOptTmp;
  _POSTGRESQL_DATA *psSessionData;
  
  psSessionData = malloc(sizeof(_POSTGRESQL_DATA));
  memset(psSessionData, 0, sizeof(_POSTGRESQL_DATA));

  if ((argc < 0) || (argc > 1))
  {
    writeError(ERR_ERROR, "%s: Incorrect number of parameters passed to module (%d). Use \"-q\" option to display module usage.", MODULE_NAME, argc);
    return FAILURE;
  }
  else 
  {
    writeError(ERR_DEBUG_MODULE, "OMG teh %s module has been called!!", MODULE_NAME);

    for (i=0; i<argc; i++) {
      pOptTmp = malloc( strlen(argv[i]) + 1);
      memset(pOptTmp, 0, strlen(argv[i]) + 1);
      strncpy(pOptTmp, argv[i], strlen(argv[i]));
      writeError(ERR_DEBUG_MODULE, "Processing complete option: %s", pOptTmp);
      pOpt = strtok_r(pOptTmp, ":", &strtok_ptr);
      writeError(ERR_DEBUG_MODULE, "Processing option: %s", pOpt);

      if (strcmp(pOpt, "DB") == 0)
      {
        pOpt = strtok_r(NULL, "\0", &strtok_ptr);
        writeError(ERR_DEBUG_MODULE, "Processing option parameter: %s", pOpt);

        if ( pOpt )
        {
          psSessionData->szDB = malloc(strlen(pOpt) + 1);
          memset(psSessionData->szDB, 0, strlen(pOpt) + 1);
          strncpy((char *)psSessionData->szDB, pOpt, strlen(pOpt));
        }
        else
          writeError(ERR_WARNING, "Method DB requires value to be set.");
      }
      else
         writeError(ERR_WARNING, "Invalid method: %s.", pOpt);

      free(pOptTmp);
    }

    initModule(logins, psSessionData);
  }  

  FREE(psSessionData);
  return SUCCESS;
}

int initModule(sLogin* psLogin, _POSTGRESQL_DATA *_psSessionData)
{
  int hSocket = -1;
  enum MODULE_STATE nState = MSTATE_NEW;
  sCredentialSet *psCredSet = NULL;
  sConnectParams params;

  psCredSet = malloc( sizeof(sCredentialSet) );
  memset(psCredSet, 0, sizeof(sCredentialSet));

  if (getNextCredSet(psLogin, psCredSet) == FAILURE)
  {
    writeError(ERR_ERROR, "[%s] Error retrieving next credential set to test.", MODULE_NAME);
    nState = MSTATE_COMPLETE;
  }
  else if (psCredSet->psUser)
  {
    writeError(ERR_DEBUG_MODULE, "[%s] module started for host: %s user: %s", MODULE_NAME, psLogin->psServer->pHostIP, psCredSet->psUser->pUser);
  }
  else
  {
    writeError(ERR_DEBUG_MODULE, "[%s] module started for host: %s - no more available users to test.", MODULE_NAME);
    nState = MSTATE_COMPLETE;
  }

  memset(&params, 0, sizeof(sConnectParams));
  params.nPort = PORT_POSTGRESQL;
  initConnectionParams(psLogin, &params);

  /* set database name, if not specified by user */
  if (_psSessionData->szDB == NULL)
  {
    _psSessionData->szDB = malloc(10);
    memset(_psSessionData->szDB, 0, 10);
    sprintf(_psSessionData->szDB, "template1");
  }
  
  writeError(ERR_DEBUG_MODULE, "[%s] Set database name: %s", MODULE_NAME, _psSessionData->szDB);

  while (nState != MSTATE_COMPLETE)
  {  
    switch(nState)
    {
      case MSTATE_NEW:
        if (hSocket > 0)
          medusaDisconnect(hSocket);

        if (psLogin->psServer->psHost->iUseSSL > 0)
          hSocket = medusaConnectSSL(&params);
        else
          hSocket = medusaConnect(&params);

        if (hSocket < 0) 
        {
          writeError(ERR_NOTICE, "%s: failed to connect, port %d was not open on %s", MODULE_NAME, params.nPort, psLogin->psServer->pHostIP);
          psLogin->iResult = LOGIN_RESULT_UNKNOWN;
          return FAILURE;
        }

        writeError(ERR_DEBUG_MODULE, "Connected");
        nState = MSTATE_RUNNING;

        break;
      case MSTATE_RUNNING:
        nState = tryLogin(&psLogin, _psSessionData, psCredSet->psUser->pUser, psCredSet->pPass);

        if (psLogin->iResult != LOGIN_RESULT_UNKNOWN)
        {
          if (getNextCredSet(psLogin, psCredSet) == FAILURE)
          {
            writeError(ERR_ERROR, "[%s] Error retrieving next credential set to test.", MODULE_NAME);
            nState = MSTATE_EXITING;
          }
          else
          {
            if (psCredSet->iStatus == CREDENTIAL_DONE)
            {
              writeError(ERR_DEBUG_MODULE, "[%s] No more available credential sets to test.", MODULE_NAME);
              nState = MSTATE_EXITING;
            }
            else if (psCredSet->iStatus == CREDENTIAL_NEW_USER)
            {
              writeError(ERR_DEBUG_MODULE, "[%s] Starting testing for new user: %s.", MODULE_NAME, psCredSet->psUser->pUser);
              nState = MSTATE_NEW;
            }
            else
              writeError(ERR_DEBUG_MODULE, "[%s] Next credential set - user: %s password: %s", MODULE_NAME, psCredSet->psUser->pUser, psCredSet->pPass);
          }
        }
        break;
      case MSTATE_EXITING:
        if (hSocket > 0)
          medusaDisconnect(hSocket);
        hSocket = -1;
        nState = MSTATE_COMPLETE;
        break;
      default:
        writeError(ERR_CRITICAL, "Unknown %s module state %d", MODULE_NAME, nState);
        if (hSocket > 0)
          medusaDisconnect(hSocket);
        hSocket = -1;
        psLogin->iResult = LOGIN_RESULT_UNKNOWN;
        return FAILURE;
    }  
  }

  FREE(psCredSet);
  return SUCCESS;
}

/* Module Specific Functions */

int tryLogin(sLogin** psLogin, _POSTGRESQL_DATA* _psSessionData, char* szLogin, char* szPassword)
{
  char *szConnectionString;
  int iRet;

  szConnectionString = malloc(strlen((*psLogin)->psServer->pHostIP) + strlen(szLogin) + strlen(szPassword) + strlen(_psSessionData->szDB) + 47);
  memset(szConnectionString, 0, strlen((*psLogin)->psServer->pHostIP) + strlen(szLogin) + strlen(szPassword) + strlen(_psSessionData->szDB) + 47);
  
  sprintf(szConnectionString, "host = '%s' dbname = '%s' user = '%s' password = '%s' ", (*psLogin)->psServer->pHostIP, _psSessionData->szDB, szLogin, szPassword);

  if (PQstatus(PQconnectdb(szConnectionString)) == CONNECTION_OK)
  {
    writeError(ERR_DEBUG_MODULE, "%s : Login attempt successful.", MODULE_NAME);
    (*psLogin)->iResult = LOGIN_RESULT_SUCCESS;
    iRet = MSTATE_EXITING;
  }
  else
  {
    writeError(ERR_DEBUG_MODULE, "%s : Login attempt failed.", MODULE_NAME);
    (*psLogin)->iResult = LOGIN_RESULT_FAIL;
    iRet = MSTATE_NEW;
  }
  
  setPassResult((*psLogin), szPassword);

  free(szConnectionString);
  return(iRet);
}

#else

void summaryUsage(char **ppszSummary)
{
  // Memory for ppszSummary will be allocated here - caller is responsible for freeing it
  int  iLength = 0;


  if (*ppszSummary == NULL)
  {
    iLength = strlen(MODULE_SUMMARY_USAGE) + strlen(MODULE_VERSION) + strlen(MODULE_SUMMARY_FORMAT) + strlen(LIBPQ_WARNING) + 1;
    *ppszSummary = (char*)malloc(iLength);
    memset(*ppszSummary, 0, iLength);
    snprintf(*ppszSummary, iLength, MODULE_SUMMARY_FORMAT_WARN, MODULE_SUMMARY_USAGE, MODULE_VERSION, LIBPQ_WARNING);
  }
  else
  {
    writeError(ERR_ERROR, "%s reports an error in summaryUsage() : ppszSummary must be NULL when called", MODULE_NAME);
  }
}

void showUsage()
{
  writeVerbose(VB_NONE, "%s (%s) %s :: %s\n", MODULE_NAME, MODULE_VERSION, MODULE_AUTHOR, MODULE_SUMMARY_USAGE);
  writeVerbose(VB_NONE, "** Module was not properly built. Is LIBPQ installed correctly? **");
  writeVerbose(VB_NONE, "");
}

int go(sLogin* logins, int argc, char *argv[])
{
  writeVerbose(VB_NONE, "%s (%s) %s :: %s\n", MODULE_NAME, MODULE_VERSION, MODULE_AUTHOR, MODULE_SUMMARY_USAGE);
  writeVerbose(VB_NONE, "** Module was not properly built. Is LIBPQ installed correctly? **");
  writeVerbose(VB_NONE, "");
  return FAILURE;
}

#endif

