/* ====================================================================
 * Copyright (c) 1995 The Apache Group.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the Apache Group
 *    for use in the Apache HTTP server project (http://www.apache.org/)."
 *
 * 4. The names "Apache Server" and "Apache Group" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission.
 *
 * 5. Redistributions of any form whatsoever must retain the following
 * acknowledgment:
 *    "This product includes software developed by the Apache Group
 *    for use in the Apache HTTP server project (http://www.apache.org/)."
 *
 * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE APACHE GROUP OR
 * IT'S CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Group and was originally based
 * on public domain software written at the National Center for
 * Supercomputing Applications, University of Illinois, Urbana-Champaign.
 * For more information on the Apache Group and the Apache HTTP server
 * project, please see <http://www.apache.org/>.
 *
 */

/* ====================================================================
 * accessCookie Module
 * ====================================================================
 * Author:  Jürgen eT Mangler
 * eMail:   juergen.mangler@univie.ac.at, et@wkv.at
 *
 * Version: 0.4 (Clueless)
 * Date:    27 Sep 2003
 *
 */

#include "httpd.h"
#include "http_core.h"
#include "http_config.h"
#include "http_log.h"
#include "http_request.h"
#include "mysql.h"

typedef struct {
  int   Engine;
  int   Timetrack;
  int   Timetrack_Distance;
  char *Server;
  char *Database;
  char *Table;
  char *Username;
  char *Password; 
  char *Name;
  int   Method;
  char *where;
} accessCookie_conf;

module MODULE_VAR_EXPORT accessCookie_module;

static void *create_accessCookie_dir_config(pool *p, char *dummy) {
  accessCookie_conf* conf = (accessCookie_conf *) ap_pcalloc(p, sizeof(accessCookie_conf));
  conf->Engine             = 0;
  conf->Timetrack          = 0;
  conf->Timetrack_Distance = 0;
  conf->Server             = NULL;
  conf->Database           = NULL;
  conf->Table              = NULL;
  conf->Username           = NULL;
  conf->Password           = NULL;
  conf->Name               = NULL;
  conf->Method             = 0;
  conf->where              = NULL;
  return (void *) conf;
}

static const int checkDigit(cmd_parms *cmd, char *eTest) {
  return (!strcmp(ap_psprintf(cmd->pool,"%i",atoi(eTest)),eTest) ? atoi(eTest) : 0);
}

static const char *accessCookie_timetrack (cmd_parms *cmd, void *dv, char *arg) {
  accessCookie_conf *conf = (accessCookie_conf *) dv;

  switch (*((int *)cmd->info)) {
    case 1:
      if      (!(strcasecmp(arg, "off")))      { conf->Timetrack = 0; }
      else if (!(strcasecmp(arg, "static")))   { conf->Timetrack = 1; }
      else if (!(strcasecmp(arg, "distance"))) { conf->Timetrack = 2; }
      else {
        return "accessCookie_Timetrack takes one argument, off|static|distance";    
      }
      break;
    case 2:
      conf->Timetrack_Distance = checkDigit(cmd,arg);
      if (!conf->Timetrack_Distance) {
        return "accessCookie_Timetrack_Distance takes one argument, a digit > 0";
      }
      break;
  }    

  return NULL;
}

static const char *accessCookie_engine (cmd_parms *cmd, void *dv, char *arg) {
  accessCookie_conf *conf = (accessCookie_conf *) dv;

  if      (!(strcasecmp(arg, "on")))  { conf->Engine = 1; }
  else if (!(strcasecmp(arg, "off"))) { conf->Engine = 0; }
  else {
    return "accessCookie_Engine takes one argument, on|off";    
  } 

  return NULL;
}

static const char *accessCookie_str (cmd_parms *cmd, void *dv, char *arg) {
  accessCookie_conf *conf = (accessCookie_conf *) dv;

  switch (*((int *)cmd->info)) {
    case 1: conf->Server   = arg;break;
    case 2: conf->Database = arg;break;
    case 3: conf->Table    = arg;break;
    case 4: conf->Username = arg;break;
    case 5: conf->Password = arg;break;
    case 6: conf->Name     = arg;break;
  }
  
  return NULL;
}

static const char *accessCookie_data (cmd_parms *cmd, void *dv, char *arg1, char *arg2) {
  accessCookie_conf  *conf = (accessCookie_conf *) dv;

  if ((!strcasecmp(arg1, "use")) && (!strcasecmp(arg2, "all"))) {
    conf->Method = 1;
    return NULL;
  }
  else if ((!strcasecmp(arg1, "use")) && (!strcasecmp(arg2, "none"))) {
    conf->Method = 2;
    return NULL;
  }
  else if ((!strcasecmp(arg1, "keep")) && (!strcasecmp(arg2, "alive"))) {
    conf->Method = 4;
    return NULL;
  }
  else if (!strcasecmp(arg1, "where")) {
    conf->Method = 3;
    conf->where  = arg2;
    return NULL;
  }

  return "allowCookie takes two arguments, [use all|none] | [where mySQL-WHERE-Statement]";
}

static int accessCookie_Server             = 1;
static int accessCookie_Database           = 2;
static int accessCookie_Table              = 3;
static int accessCookie_Username           = 4;
static int accessCookie_Password           = 5;
static int accessCookie_Name               = 6;
static int accessCookie_Timetrack          = 1;
static int accessCookie_Timetrack_Distance = 2;

static const command_rec access_cmds[] = {
    {"accessCookie_Engine",             accessCookie_engine,    NULL,                             OR_LIMIT, TAKE1, "on|off"},
    {"accessCookie_Server",             accessCookie_str,       &accessCookie_Server,             OR_LIMIT, TAKE1, "Server-Name"},
    {"accessCookie_Database",           accessCookie_str,       &accessCookie_Database,           OR_LIMIT, TAKE1, "Database-Name"},
    {"accessCookie_Table",              accessCookie_str,       &accessCookie_Table,              OR_LIMIT, TAKE1, "Table-Name"},
    {"accessCookie_Username",           accessCookie_str,       &accessCookie_Username,           OR_LIMIT, TAKE1, "Username"},
    {"accessCookie_Password",           accessCookie_str,       &accessCookie_Password,           OR_LIMIT, TAKE1, "Password"},
    {"accessCookie_Name",               accessCookie_str,       &accessCookie_Name,               OR_LIMIT, TAKE1, "Name of Cookie"},
    {"accessCookie_Timetrack",          accessCookie_timetrack, &accessCookie_Timetrack,          OR_LIMIT, TAKE1, "off|static|distance"},    
    {"accessCookie_Timetrack_Distance", accessCookie_timetrack, &accessCookie_Timetrack_Distance, OR_LIMIT, TAKE1, "a digit > 0"},
    {"allowCookie",                     accessCookie_data,      NULL,                             OR_LIMIT, TAKE2, "[use all|none] | [keep alive] | [where mySQL-WHERE-Statement]"},
    {NULL}
};

static void addEnvir (MYSQL_RES *result, table *env, pool *p) {
  MYSQL_ROW currow  = mysql_fetch_row (result);
  MYSQL_FIELD *curfield;
  int i = 0;

  for (i=0; i < mysql_num_fields(result); i++) {
    curfield = mysql_fetch_field_direct(result,i);
    if (!strncmp("accessCookie_", curfield->name ,13)) {
      ap_table_setn (env,ap_pstrdup(p,curfield->name),ap_pstrdup(p,currow[i]));
    }
  }
}

static int getQuery (char *query, accessCookie_conf *conf, table *env, pool *p) {
  MYSQL      connection;
  MYSQL_RES *results;
  int        ret;
  
  mysql_init(&connection);
  if (!mysql_real_connect (&connection,conf->Server,conf->Username,conf->Password,conf->Database,0,NULL,0)) {
    ret=1;goto retA;
  }
  if (mysql_query (&connection, query)) {
    ret=2;goto retB;
  }
  if (!(results = mysql_store_result (&connection))) {
    ret=3;goto retB;
  }
  if      (mysql_num_rows(results) == 0) ret=4;
  else if (mysql_num_rows(results) > 1)  ret=5;
  else { 
    ret=6;
    addEnvir(results,env,p);
  }

  mysql_free_result(results);

retB:
  mysql_close(&connection);
retA:
  return ret;
}

static int setDistance (accessCookie_conf *conf, char *eWhere, pool *rPool) {
  MYSQL  connection;
  char  *query = ap_pstrcat(rPool, "update ", conf->Table, " set eTIME=DATE_ADD(NOW(),INTERVAL ", ap_psprintf(rPool, "%i",conf->Timetrack_Distance), " SECOND)", eWhere, ";", NULL);
  int    ret   = 0;

  mysql_init(&connection);
  if (!mysql_real_connect (&connection,conf->Server,conf->Username,conf->Password,conf->Database,0,NULL,0)) goto retA;
  if (mysql_query (&connection, query)) goto retB;
  ret=1;

retB:
  mysql_close(&connection);
retA:
  return ret;
}

static char *getCookie(request_rec *r,char *name) {
  char *cookie;
  char *part;
  char *value = "";

  if (!(cookie = (char *)ap_table_get(r->headers_in, "Cookie"))) { return NULL; }
  part = ap_pstrcat (r->pool, cookie, ";", NULL);

  for (part=strtok(part, " ;\n\r\t\f"); (part); part=strtok(NULL, " ;\n\r\t\f")) {
    while (part && !(value = strchr (part, (int) '='))) {
      part = strtok (NULL, " ;\n\r\t\f");
    }  
    if (++value) {
      if (!strcasecmp(ap_getword(r->pool,(const char **)&part,'='), name)) {
         return value;
      }
    }
  }

  return NULL;  
}

static int check_dir_accessCookie(request_rec *r) {
  accessCookie_conf  *conf   = (accessCookie_conf *) ap_get_module_config(r->per_dir_config, &accessCookie_module);
  char               *eQuery = "select * from ";
  char               *eWhere; 
  char               *value;
  char               *errText = "";
  
  if (conf->Engine == 0) return OK;
  if (conf->Method == 2) {
    errText = "%s: accessCookie - client denied";
    goto errOut;
  }
  if ((conf->Server   == NULL) || 
      (conf->Database == NULL) || 
      (conf->Table    == NULL) || 
      (conf->Username == NULL) || 
      (conf->Password == NULL) ||
      (conf->Name     == NULL) ||
      (conf->Method   == 0)) {
    errText = "%s: accessCookie - missing parameters";
    goto errOut;
  }

/*************************************************************************
 * inititalize                                                           *
 *************************************************************************/
  value  = getCookie(r,conf->Name);
  eQuery = ap_pstrcat(r->pool, eQuery, conf->Table, NULL);
  eWhere = ap_pstrcat(r->pool, " where COOKIE='", value , "'", NULL);
  if (conf->Timetrack) {
    eWhere = ap_pstrcat(r->pool, eWhere, " and eTIME>=NOW()", conf->where,  NULL);
  }

/*************************************************************************
 * keep alive                                                            *
 *************************************************************************/
  if (conf->Method == 4) {
    if (conf->Timetrack == 2) {
      if (!value) {
        ap_table_setn (r->subprocess_env,ap_pstrdup(r->pool,"accessCookie_ALIVE"),ap_pstrdup(r->pool,"0"));
        return OK;
      }  
    } else {
      errText = "%s: accessCookie - Works only in Timetrack distance mode";
      goto errOut;
    }  
  }
  
/*************************************************************************
 * use all, where                                                        *
 *************************************************************************/
  if (!value) {
    errText = "%s: accessCookie - missing cookie";
    goto errOut;
  }
  if (conf->Method == 3) { 
    eWhere = ap_pstrcat(r->pool, eWhere, " and ", conf->where,  NULL); 
  }
  
  switch (getQuery(ap_pstrcat(r->pool, eQuery, eWhere, ";", NULL),conf,r->subprocess_env,r->pool)) {
    case 1: errText = "%s: accessCookie - can't connect to server/database";goto errOut;
    case 2: errText = "%s: accessCookie - can't execute query";goto errOut;
    case 3: errText = "%s: accessCookie - can't get results from database";goto errOut;
    case 4: 
      if (conf->Method == 4) {
        ap_table_setn (r->subprocess_env,ap_pstrdup(r->pool,"accessCookie_ALIVE"),ap_pstrdup(r->pool,"0"));
        return OK;
      } else {  
        errText = "%s: accessCookie - client denied";
        goto errOut;
      }  
    case 5: errText = "%s: accessCookie - holy shit, more than one matching cookie";goto errOut;
    case 6: 
      if (conf->Timetrack == 2) {
        if (!conf->Timetrack_Distance) {
           errText = "%s: accessCookie - Timtrack_Distance not set";
           goto errOut;
        }
        if (!setDistance(conf,eWhere,r->pool)) {
          errText = "%s: accessCookie - can't update eTIME";
          goto errOut;
        }
        if (conf->Method == 4) {
          ap_table_setn (r->subprocess_env,ap_pstrdup(r->pool,"accessCookie_ALIVE"),ap_pstrdup(r->pool,"1"));
        }  
      }
      return OK;
  }

/*************************************************************************
 * forbidden                                                             *
 *************************************************************************/
errOut:
  ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, r, errText , r->filename);  
  return FORBIDDEN;
}

module MODULE_VAR_EXPORT accessCookie_module = {
    STANDARD_MODULE_STUFF,
    NULL,			                      /* initializer */
    create_accessCookie_dir_config,	/* dir config creater */
    NULL,			                      /* dir merger --- default is to override */
    NULL,			                      /* server config */
    NULL,		     	                  /* merge server config */
    access_cmds,                    /* Command Array */
    NULL,		     	                  /* handlers */
    NULL,			                      /* filename translation */
    NULL,			                      /* check_user_id */
    NULL,			                      /* check auth */
    check_dir_accessCookie,         /* check access */
    NULL, 			                    /* type_checker */
    NULL,	  		                    /* fixups */
    NULL,		 	                      /* logger */
    NULL,		 	                      /* header parser */
    NULL,		 	                      /* child_init */
    NULL,		 	                      /* child_exit */
    NULL		  	                    /* post read-request */
};