src/modules/rlm_sqlcounter/rlm_sqlcounter.c

   1 /*
   2  * rlm_sqlcounter.c
   3  *
   4  * Version:  $Id$
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  * Copyright 2001  The FreeRADIUS server project
  21  * Copyright 2001  Alan DeKok <aland@ox.org>
  22  * Copyright 2001  Kostas Kalevras <kkalev@noc.ntua.gr>
  23  */
  24
  25 /* This module is based directly on the rlm_counter module */
  26
  27
  28 #include "config.h"
  29 #include "autoconf.h"
  30 #include "libradius.h"
  31
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <ctype.h>
  36
  37 #include "radiusd.h"
  38 #include "modules.h"
  39 #include "conffile.h"
  40
  41 #include <time.h>
  42
  43
  44 static const char rcsid[] = "$Id$";
  45
  46 /*
  47  *      Define a structure for our module configuration.
  48  *
  49  *      These variables do not need to be in a structure, but it's
  50  *      a lot cleaner to do so, and a pointer to the structure can
  51  *      be used as the instance handle.
  52  */
  53 typedef struct rlm_sqlcounter_t {
  54         char *counter_name;     /* Daily-Session-Time */
  55         char *check_name;       /* Max-Daily-Session */
  56         char *key_name;         /* User-Name */
  57         char *sqlmod_inst;      /* instance of SQL module to use, usually just 'sql' */
  58         char *query;            /* SQL query to retrieve current session time */
  59         char *reset;            /* daily, weekly, monthly, never or user defined */
  60         time_t reset_time;
  61         time_t last_reset;
  62         int  key_attr;          /* attribute number for key field */
  63         int  dict_attr;         /* attribute number for the counter. */
  64 } rlm_sqlcounter_t;
  65
  66 /*
  67  *      A mapping of configuration file names to internal variables.
  68  *
  69  *      Note that the string is dynamically allocated, so it MUST
  70  *      be freed.  When the configuration file parse re-reads the string,
  71  *      it free's the old one, and strdup's the new one, placing the pointer
  72  *      to the strdup'd string into 'config.string'.  This gets around
  73  *      buffer over-flows.
  74  */
  75 static CONF_PARSER module_config[] = {
  76   { "counter-name", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,counter_name), NULL,  NULL },
  77   { "check-name", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,check_name), NULL, NULL },
  78   { "key", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,key_name), NULL, NULL },
  79   { "sqlmod-inst", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,sqlmod_inst), NULL, NULL },
  80   { "query", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,query), NULL, NULL },
  81   { "reset", PW_TYPE_STRING_PTR, offsetof(rlm_sqlcounter_t,reset), NULL,  NULL },
  82   { NULL, -1, 0, NULL, NULL }
  83 };
  84
  85
  86 static int find_next_reset(rlm_sqlcounter_t *data, time_t timeval)
  87 {
  88         int ret=0;
  89         unsigned int num=1;
  90         char last = 0;
  91         struct tm *tm, s_tm;
  92
  93         tm = localtime_r(&timeval, &s_tm);
  94         tm->tm_sec = tm->tm_min = 0;
  95
  96         if (data->reset == NULL)
  97                 return -1;
  98         if (isdigit(data->reset[0])){
  99                 unsigned int len=0;
 100
 101                 len = strlen(data->reset);
 102                 if (len == 0)
 103                         return -1;
 104                 last = data->reset[len - 1];
 105                 if (!isalpha(last))
 106                         last = 'd';
 107                 num = atoi(data->reset);
 108                 DEBUG("rlm_sqlcounter: num=%d, last=%c",num,last);
 109         }
 110         if (strcmp(data->reset, "hourly") == 0 || last == 'h') {
 111                 /*
 112                  *  Round up to the next nearest hour.
 113                  */
 114                 tm->tm_hour += num;
 115                 data->reset_time = mktime(tm);
 116         } else if (strcmp(data->reset, "daily") == 0 || last == 'd') {
 117                 /*
 118                  *  Round up to the next nearest day.
 119                  */
 120                 tm->tm_hour = 0;
 121                 tm->tm_mday += num;
 122                 data->reset_time = mktime(tm);
 123         } else if (strcmp(data->reset, "weekly") == 0 || last == 'w') {
 124                 /*
 125                  *  Round up to the next nearest week.
 126                  */
 127                 tm->tm_hour = 0;
 128                 tm->tm_mday += (7 - tm->tm_wday) +(7*(num-1));
 129                 data->reset_time = mktime(tm);
 130         } else if (strcmp(data->reset, "monthly") == 0 || last == 'm') {
 131                 tm->tm_hour = 0;
 132                 tm->tm_mday = 1;
 133                 tm->tm_mon += num;
 134                 data->reset_time = mktime(tm);
 135         } else if (strcmp(data->reset, "never") == 0) {
 136                 data->reset_time = 0;
 137         } else {
 138                 radlog(L_ERR, "rlm_sqlcounter: Unknown reset timer \"%s\"",
 139                         data->reset);
 140                 return -1;
 141         }
 142         DEBUG2("rlm_sqlcounter: Current Time: %d, Next reset %d",
 143                 (int)timeval,(int)data->reset_time);
 144
 145         return ret;
 146 }
 147
 148
 149 /*  I don't believe that this routine handles Daylight Saving Time adjustments
 150     properly.  Any suggestions?
 151 */
 152
 153 static int find_prev_reset(rlm_sqlcounter_t *data, time_t timeval)
 154 {
 155         int ret=0;
 156         unsigned int num=1;
 157         char last = 0;
 158         struct tm *tm, s_tm;
 159
 160         tm = localtime_r(&timeval, &s_tm);
 161         tm->tm_sec = tm->tm_min = 0;
 162
 163         if (data->reset == NULL)
 164                 return -1;
 165         if (isdigit(data->reset[0])){
 166                 unsigned int len=0;
 167
 168                 len = strlen(data->reset);
 169                 if (len == 0)
 170                         return -1;
 171                 last = data->reset[len - 1];
 172                 if (!isalpha(last))
 173                         last = 'd';
 174                 num = atoi(data->reset);
 175                 DEBUG("rlm_sqlcounter: num=%d, last=%c",num,last);
 176         }
 177         if (strcmp(data->reset, "hourly") == 0 || last == 'h') {
 178                 /*
 179                  *  Round down to the prev nearest hour.
 180                  */
 181                 tm->tm_hour -= num - 1;
 182                 data->last_reset = mktime(tm);
 183         } else if (strcmp(data->reset, "daily") == 0 || last == 'd') {
 184                 /*
 185                  *  Round down to the prev nearest day.
 186                  */
 187                 tm->tm_hour = 0;
 188                 tm->tm_mday -= num - 1;
 189                 data->last_reset = mktime(tm);
 190         } else if (strcmp(data->reset, "weekly") == 0 || last == 'w') {
 191                 /*
 192                  *  Round down to the prev nearest week.
 193                  */
 194                 tm->tm_hour = 0;
 195                 tm->tm_mday -= (7 - tm->tm_wday) +(7*(num-1));
 196                 data->last_reset = mktime(tm);
 197         } else if (strcmp(data->reset, "monthly") == 0 || last == 'm') {
 198                 tm->tm_hour = 0;
 199                 tm->tm_mday = 1;
 200                 tm->tm_mon -= num - 1;
 201                 data->last_reset = mktime(tm);
 202         } else if (strcmp(data->reset, "never") == 0) {
 203                 data->reset_time = 0;
 204         } else {
 205                 radlog(L_ERR, "rlm_sqlcounter: Unknown reset timer \"%s\"",
 206                         data->reset);
 207                 return -1;
 208         }
 209         DEBUG2("rlm_sqlcounter: Current Time: %d, Prev reset %d",
 210                 (int)timeval,(int)data->last_reset);
 211
 212         return ret;
 213 }
 214
 215
 216 /*
 217  *      Replace %<whatever> in a string.
 218  *
 219  *      %b      last_reset
 220  *      %e      reset_time
 221  *      %k      key_name
 222  *      %S      sqlmod_inst
 223  *
 224  */
 225
 226 static int sqlcounter_expand(char *out, int outlen, const char *fmt, void *instance)
 227 {
 228         rlm_sqlcounter_t *data = (rlm_sqlcounter_t *) instance;
 229         int c,freespace;
 230         const char *p;
 231         char *q;
 232         char tmpdt[40]; /* For temporary storing of dates */
 233         int openbraces=0;
 234
 235         q = out;
 236         for (p = fmt; *p ; p++) {
 237         /* Calculate freespace in output */
 238         freespace = outlen - (q - out);
 239                 if (freespace <= 1)
 240                         break;
 241                 c = *p;
 242                 if ((c != '%') && (c != '$') && (c != '\\')) {
 243                         /*
 244                          * We check if we're inside an open brace.  If we are
 245                          * then we assume this brace is NOT literal, but is
 246                          * a closing brace and apply it
 247                          */
 248                         if((c == '}') && openbraces) {
 249                                 openbraces--;
 250                                 continue;
 251                         }
 252                         *q++ = *p;
 253                         continue;
 254                 }
 255                 if (*++p == '\0') break;
 256                 if (c == '\\') switch(*p) {
 257                         case '\\':
 258                                 *q++ = *p;
 259                                 break;
 260                         case 't':
 261                                 *q++ = '\t';
 262                                 break;
 263                         case 'n':
 264                                 *q++ = '\n';
 265                                 break;
 266                         default:
 267                                 *q++ = c;
 268                                 *q++ = *p;
 269                                 break;
 270
 271                 } else if (c == '%') switch(*p) {
 272
 273                         case '%':
 274                                 *q++ = *p;
 275                         case 'b': /* last_reset */
 276                                 sprintf(tmpdt, "%lu", data->last_reset);
 277                                 strNcpy(q, tmpdt, freespace);
 278                                 q += strlen(q);
 279                                 break;
 280                         case 'e': /* reset_time */
 281                                 sprintf(tmpdt, "%lu", data->reset_time);
 282                                 strNcpy(q, tmpdt, freespace);
 283                                 q += strlen(q);
 284                                 break;
 285                         case 'k': /* Key Name */
 286                                 strNcpy(q, data->key_name, freespace);
 287                                 q += strlen(q);
 288                                 break;
 289                         case 'S': /* SQL module instance */
 290                                 strNcpy(q, data->sqlmod_inst, freespace);
 291                                 q += strlen(q);
 292                                 break;
 293                         default:
 294                                 *q++ = '%';
 295                                 *q++ = *p;
 296                                 break;
 297                 }
 298         }
 299         *q = '\0';
 300
 301         DEBUG2("sqlcounter_expand:  '%s'", out);
 302
 303         return strlen(out);
 304 }
 305
 306
 307 /*
 308  *      See if the counter matches.
 309  */
 310 static int sqlcounter_cmp(void *instance, REQUEST *req, VALUE_PAIR *request, VALUE_PAIR *check,
 311                 VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 312 {
 313         rlm_sqlcounter_t *data = (rlm_sqlcounter_t *) instance;
 314         int counter;
 315         char querystr[MAX_STRING_LEN];
 316         char responsestr[MAX_STRING_LEN];
 317
 318         check_pairs = check_pairs; /* shut the compiler up */
 319         reply_pairs = reply_pairs;
 320
 321         /* first, expand %k, %b and %e in query */
 322         sqlcounter_expand(querystr, MAX_STRING_LEN, data->query, instance);
 323
 324         /* second, xlat any request attribs in query */
 325         radius_xlat(responsestr, MAX_STRING_LEN, querystr, req, NULL);
 326
 327         /* third, wrap query with sql module call & expand */
 328         sprintf(querystr, "%%{%%S:%s}", responsestr);
 329         sqlcounter_expand(responsestr, MAX_STRING_LEN, querystr, instance);
 330
 331         /* Finally, xlat resulting SQL query */
 332         radius_xlat(querystr, MAX_STRING_LEN, responsestr, req, NULL);
 333
 334         counter = atoi(querystr);
 335
 336         return counter - check->lvalue;
 337 }
 338
 339
 340 /*
 341  *      Do any per-module initialization that is separate to each
 342  *      configured instance of the module.  e.g. set up connections
 343  *      to external databases, read configuration files, set up
 344  *      dictionary entries, etc.
 345  *
 346  *      If configuration information is given in the config section
 347  *      that must be referenced in later calls, store a handle to it
 348  *      in *instance otherwise put a null pointer there.
 349  */
 350 static int sqlcounter_instantiate(CONF_SECTION *conf, void **instance)
 351 {
 352         rlm_sqlcounter_t *data;
 353         DICT_ATTR *dattr;
 354         ATTR_FLAGS flags;
 355         time_t now;
 356
 357         /*
 358          *      Set up a storage area for instance data
 359          */
 360         data = rad_malloc(sizeof(*data));
 361
 362         /*
 363          *      If the configuration parameters can't be parsed, then
 364          *      fail.
 365          */
 366         if (cf_section_parse(conf, data, module_config) < 0) {
 367                 free(data);
 368                 return -1;
 369         }
 370
 371         /*
 372          *      Discover the attribute number of the key.
 373          */
 374         if (data->key_name == NULL) {
 375                 radlog(L_ERR, "rlm_sqlcounter: 'key' must be set.");
 376                 exit(0);
 377         }
 378         dattr = dict_attrbyname(data->key_name);
 379         if (dattr == NULL) {
 380                 radlog(L_ERR, "rlm_sqlcounter: No such attribute %s",
 381                                 data->key_name);
 382                 return -1;
 383         }
 384         data->key_attr = dattr->attr;
 385
 386
 387         /*
 388          *  Create a new attribute for the counter.
 389          */
 390         if (data->counter_name == NULL) {
 391                 radlog(L_ERR, "rlm_sqlcounter: 'counter-name' must be set.");
 392                 exit(0);
 393         }
 394
 395         memset(&flags, 0, sizeof(flags));
 396         dict_addattr(data->counter_name, 0, PW_TYPE_INTEGER, -1, flags);
 397         dattr = dict_attrbyname(data->counter_name);
 398         if (dattr == NULL) {
 399                 radlog(L_ERR, "rlm_sqlcounter: Failed to create counter attribute %s",
 400                                 data->counter_name);
 401                 return -1;
 402         }
 403         data->dict_attr = dattr->attr;
 404         DEBUG2("rlm_sqlcounter: Counter attribute %s is number %d",
 405                         data->counter_name, data->dict_attr);
 406
 407         /*
 408          * Create a new attribute for the check item.
 409          */
 410         if (data->check_name == NULL) {
 411                 radlog(L_ERR, "rlm_sqlcounter: 'check-name' must be set.");
 412                 exit(0);
 413         }
 414         dict_addattr(data->check_name, 0, PW_TYPE_INTEGER, -1, flags);
 415         dattr = dict_attrbyname(data->check_name);
 416         if (dattr == NULL) {
 417                 radlog(L_ERR, "rlm_sqlcounter: Failed to create check attribute %s",
 418                                 data->counter_name);
 419                 return -1;
 420         }
 421         DEBUG2("rlm_sqlcounter: Check attribute %s is number %d",
 422                         data->check_name, dattr->attr);
 423
 424         /*
 425          *  Discover the end of the current time period.
 426          */
 427         if (data->reset == NULL) {
 428                 radlog(L_ERR, "rlm_sqlcounter: 'reset' must be set.");
 429                 exit(0);
 430         }
 431         now = time(NULL);
 432         data->reset_time = 0;
 433
 434         if (find_next_reset(data,now) == -1)
 435                 return -1;
 436
 437         /*
 438          *  Discover the beginning of the current time period.
 439          */
 440         data->last_reset = 0;
 441
 442         if (find_prev_reset(data,now) == -1)
 443                 return -1;
 444
 445
 446         /*
 447          *      Register the counter comparison operation.
 448          */
 449         paircompare_register(data->dict_attr, 0, sqlcounter_cmp, data);
 450
 451         *instance = data;
 452
 453         return 0;
 454 }
 455
 456 /*
 457  *      Find the named user in this modules database.  Create the set
 458  *      of attribute-value pairs to check and reply with for this user
 459  *      from the database. The authentication code only needs to check
 460  *      the password, the rest is done here.
 461  */
 462 static int sqlcounter_authorize(void *instance, REQUEST *request)
 463 {
 464         rlm_sqlcounter_t *data = (rlm_sqlcounter_t *) instance;
 465         int ret=RLM_MODULE_NOOP;
 466         int counter=0;
 467         int res=0;
 468         DICT_ATTR *dattr;
 469         VALUE_PAIR *key_vp, *check_vp;
 470         VALUE_PAIR *reply_item;
 471         char msg[128];
 472         char querystr[MAX_STRING_LEN];
 473         char responsestr[MAX_STRING_LEN];
 474
 475         /* quiet the compiler */
 476         instance = instance;
 477         request = request;
 478
 479         /*
 480          *      Before doing anything else, see if we have to reset
 481          *      the counters.
 482          */
 483         if (data->reset_time && (data->reset_time <= request->timestamp)) {
 484
 485                 /*
 486                  *      Re-set the next time and prev_time for this counters range
 487                  */
 488                 data->last_reset = data->reset_time;
 489                 find_next_reset(data,request->timestamp);
 490         }
 491
 492
 493         /*
 494          *      Look for the key.  User-Name is special.  It means
 495          *      The REAL username, after stripping.
 496          */
 497         DEBUG2("rlm_sqlcounter: Entering module authorize code");
 498         key_vp = (data->key_attr == PW_USER_NAME) ? request->username : pairfind(request->packet->vps, data->key_attr);
 499         if (key_vp == NULL) {
 500                 DEBUG2("rlm_sqlcounter: Could not find Key value pair");
 501                 return ret;
 502         }
 503
 504         /*
 505          *      Look for the check item
 506          */
 507         if ((dattr = dict_attrbyname(data->check_name)) == NULL) {
 508                 return ret;
 509         }
 510         /* DEBUG2("rlm_sqlcounter: Found Check item attribute %d", dattr->attr); */
 511         if ((check_vp= pairfind(request->config_items, dattr->attr)) == NULL) {
 512                 DEBUG2("rlm_sqlcounter: Could not find Check item value pair");
 513                 return ret;
 514         }
 515
 516         /* first, expand %k, %b and %e in query */
 517         sqlcounter_expand(querystr, MAX_STRING_LEN, data->query, instance);
 518
 519         /* second, xlat any request attribs in query */
 520         radius_xlat(responsestr, MAX_STRING_LEN, querystr, request, NULL);
 521
 522         /* third, wrap query with sql module & expand */
 523         sprintf(querystr, "%%{%%S:%s}", responsestr);
 524         sqlcounter_expand(responsestr, MAX_STRING_LEN, querystr, instance);
 525
 526         /* Finally, xlat resulting SQL query */
 527         radius_xlat(querystr, MAX_STRING_LEN, responsestr, request, NULL);
 528
 529         counter = atoi(querystr);
 530
 531
 532         /*
 533          * Check if check item > counter
 534          */
 535         res=check_vp->lvalue - counter;
 536         if (res > 0) {
 537                 DEBUG2("rlm_sqlcounter: (Check item - counter) is greater than zero");
 538                 /*
 539                  *      We are assuming that simultaneous-use=1. But
 540                  *      even if that does not happen then our user
 541                  *      could login at max for 2*max-usage-time Is
 542                  *      that acceptable?
 543                  */
 544
 545                 /*
 546                  *      User is allowed, but set Session-Timeout.
 547                  *      Stolen from main/auth.c
 548                  */
 549
 550                 /*
 551                  *      If we are near a reset then add the next
 552                  *      limit, so that the user will not need to
 553                  *      login again
 554                  */
 555                 if (data->reset_time && (
 556                         res >= (data->reset_time - request->timestamp))) {
 557                         res += check_vp->lvalue;
 558                 }
 559
 560                 if ((reply_item = pairfind(request->reply->vps, PW_SESSION_TIMEOUT)) != NULL) {
 561                         if (reply_item->lvalue > res)
 562                                 reply_item->lvalue = res;
 563                 } else {
 564                         if ((reply_item = paircreate(PW_SESSION_TIMEOUT, PW_TYPE_INTEGER)) == NULL) {
 565                                 radlog(L_ERR|L_CONS, "no memory");
 566                                 return RLM_MODULE_NOOP;
 567                         }
 568                         reply_item->lvalue = res;
 569                         pairadd(&request->reply->vps, reply_item);
 570                 }
 571
 572                 ret=RLM_MODULE_OK;
 573
 574                 DEBUG2("rlm_sqlcounter: Authorized user %s, check_item=%d, counter=%d",
 575                                 key_vp->strvalue,check_vp->lvalue,counter);
 576                 DEBUG2("rlm_sqlcounter: Sent Reply-Item for user %s, Type=Session-Timeout, value=%d",
 577                                 key_vp->strvalue,reply_item->lvalue);
 578         }
 579         else{
 580                 char module_fmsg[MAX_STRING_LEN];
 581                 VALUE_PAIR *module_fmsg_vp;
 582
 583                 DEBUG2("rlm_sqlcounter: (Check item - counter) is less than zero");
 584
 585                 /*
 586                  * User is denied access, send back a reply message
 587                 */
 588                 sprintf(msg, "Your maximum %s usage time has been reached", data->reset);
 589                 reply_item=pairmake("Reply-Message", msg, T_OP_EQ);
 590                 pairadd(&request->reply->vps, reply_item);
 591
 592                 snprintf(module_fmsg, sizeof(module_fmsg), "rlm_sqlcounter: Maximum %s usage time reached", data->reset);
 593                 module_fmsg_vp = pairmake("Module-Failure-Message", module_fmsg, T_OP_EQ);
 594                 pairadd(&request->packet->vps, module_fmsg_vp);
 595
 596                 ret=RLM_MODULE_REJECT;
 597
 598                 DEBUG2("rlm_sqlcounter: Rejected user %s, check_item=%d, counter=%d",
 599                                 key_vp->strvalue,check_vp->lvalue,counter);
 600         }
 601
 602         return ret;
 603 }
 604
 605 static int sqlcounter_detach(void *instance)
 606 {
 607         rlm_sqlcounter_t *data = (rlm_sqlcounter_t *) instance;
 608
 609         paircompare_unregister(data->dict_attr, sqlcounter_cmp);
 610         free(data->reset);
 611         free(data->query);
 612         free(data->check_name);
 613         free(data->sqlmod_inst);
 614         free(data->counter_name);
 615
 616         free(instance);
 617         return 0;
 618 }
 619
 620 /*
 621  *      The module name should be the only globally exported symbol.
 622  *      That is, everything else should be 'static'.
 623  *
 624  *      If the module needs to temporarily modify it's instantiation
 625  *      data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 626  *      The server will then take care of ensuring that the module
 627  *      is single-threaded.
 628  */
 629 module_t rlm_sqlcounter = {
 630         "SQL Counter",
 631         RLM_TYPE_THREAD_SAFE,           /* type */
 632         NULL,                           /* initialization */
 633         sqlcounter_instantiate,         /* instantiation */
 634         {
 635                 NULL,                   /* authentication */
 636                 sqlcounter_authorize,   /* authorization */
 637                 NULL,                   /* preaccounting */
 638                 NULL,                   /* accounting */
 639                 NULL                    /* checksimul */
 640         },
 641         sqlcounter_detach,              /* detach */
 642         NULL,                           /* destroy */
 643 };
 644