src/modules/rlm_attr_rewrite/rlm_attr_rewrite.c

   1 /*
   2  * rlm_attr_rewrite.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 2002  The FreeRADIUS server project
  21  * Copyright 2002  Kostas Kalevras <kkalev@noc.ntua.gr>
  22  */
  23
  24 #include "config.h"
  25 #include "autoconf.h"
  26 #include "libradius.h"
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include "config.h"
  32 #ifdef HAVE_REGEX_H
  33 #       include <regex.h>
  34 #endif
  35
  36 #include "radiusd.h"
  37 #include "modules.h"
  38 #include "conffile.h"
  39
  40 #define RLM_REGEX_INPACKET 0
  41 #define RLM_REGEX_INCONFIG 1
  42 #define RLM_REGEX_INREPLY  2
  43 #define RLM_REGEX_INPROXY 3
  44 #define RLM_REGEX_INPROXYREPLY 4
  45
  46 static const char rcsid[] = "$Id$";
  47
  48 typedef struct rlm_attr_rewrite_t {
  49         char *attribute;        /* The attribute to search for */
  50         int  attr_num;          /* The attribute number */
  51         char *search;           /* The pattern to search for */
  52         int search_len;         /* The length of the search pattern */
  53         char *searchin_str;     /* The VALUE_PAIR list to search in. Can be either packet,reply,proxy,proxy_reply or config */
  54         char searchin;          /* The same as above just coded as a number for speed */
  55         char *replace;          /* The replacement */
  56         int replace_len;        /* The length of the replacement string */
  57         int  append;            /* Switch to control append mode (1,0) */
  58         int  nocase;            /* Ignore case */
  59         int  new_attr;          /* Boolean. Do we create a new attribute or not? */
  60         int  num_matches;       /* Maximum number of matches */
  61         char *name;             /* The module name */
  62 } rlm_attr_rewrite_t;
  63
  64
  65 static CONF_PARSER module_config[] = {
  66   { "attribute", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,attribute), NULL, NULL },
  67   { "searchfor", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,search), NULL, NULL },
  68   { "searchin",  PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,searchin_str), NULL, "packet" },
  69   { "replacewith", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,replace), NULL, NULL },
  70   { "append", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,append),NULL, "no" },
  71   { "ignore_case", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,nocase), NULL, "yes" },
  72   { "new_attribute", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,new_attr), NULL, "no" },
  73   { "max_matches", PW_TYPE_INTEGER, offsetof(rlm_attr_rewrite_t,num_matches), NULL, "10" },
  74   { NULL, -1, 0, NULL, NULL }
  75 };
  76
  77
  78 static int attr_rewrite_instantiate(CONF_SECTION *conf, void **instance)
  79 {
  80         rlm_attr_rewrite_t *data;
  81         DICT_ATTR *dattr;
  82         char *instance_name = NULL;
  83
  84         /*
  85          *      Set up a storage area for instance data
  86          */
  87         data = rad_malloc(sizeof(*data));
  88         if (!data) {
  89                 return -1;
  90         }
  91         memset(data, 0, sizeof(*data));
  92
  93         /*
  94          *      If the configuration parameters can't be parsed, then
  95          *      fail.
  96          */
  97         if (cf_section_parse(conf, data, module_config) < 0) {
  98                 free(data);
  99                 return -1;
 100         }
 101
 102         /*
 103          *      Discover the attribute number of the key.
 104          */
 105         if (data->attribute == NULL) {
 106                 radlog(L_ERR, "rlm_attr_rewrite: 'attribute' must be set.");
 107                 return -1;
 108         }
 109         if (data->search == NULL || data->replace == NULL) {
 110                 radlog(L_ERR, "rlm_attr_rewrite: search/replace strings must be set.");
 111                 return -1;
 112         }
 113         data->search_len = strlen(data->search);
 114         data->replace_len = strlen(data->replace);
 115
 116         if (data->replace_len == 0 && data->new_attr){
 117                 radlog(L_ERR, "rlm_attr_rewrite: replace string must not be zero length in order to create new attribute.");
 118                 return -1;
 119         }
 120
 121         if (data->num_matches < 1 || data->num_matches > MAX_STRING_LEN) {
 122                 radlog(L_ERR, "rlm_attr_rewrite: Illegal range for match number.");
 123                 return -1;
 124         }
 125         if (data->searchin_str == NULL) {
 126                 radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 127                 data->searchin = RLM_REGEX_INPACKET;
 128         }
 129         else{
 130                 if (strcmp(data->searchin_str, "packet") == 0)
 131                         data->searchin = RLM_REGEX_INPACKET;
 132                 else if (strcmp(data->searchin_str, "config") == 0)
 133                         data->searchin = RLM_REGEX_INCONFIG;
 134                 else if (strcmp(data->searchin_str, "reply") == 0)
 135                         data->searchin = RLM_REGEX_INREPLY;
 136                 else if (strcmp(data->searchin_str, "proxy") == 0)
 137                         data->searchin = RLM_REGEX_INPROXY;
 138                 else if (strcmp(data->searchin_str, "proxy_reply") == 0)
 139                         data->searchin = RLM_REGEX_INPROXYREPLY;
 140                 else {
 141                         radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 142                         data->searchin = RLM_REGEX_INPACKET;
 143                 }
 144                 free((char *)data->searchin_str);
 145         }
 146         dattr = dict_attrbyname(data->attribute);
 147         if (dattr == NULL) {
 148                 radlog(L_ERR, "rlm_attr_rewrite: No such attribute %s",
 149                                 data->attribute);
 150                 return -1;
 151         }
 152         data->attr_num = dattr->attr;
 153         /* Add the module instance name */
 154         data->name = NULL;
 155         instance_name = cf_section_name2(conf);
 156         if (instance_name != NULL)
 157                 data->name = strdup(instance_name);
 158
 159
 160         *instance = data;
 161
 162         return 0;
 163 }
 164
 165 static int do_attr_rewrite(void *instance, REQUEST *request)
 166 {
 167         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 168         int ret = RLM_MODULE_NOOP;
 169         VALUE_PAIR *attr_vp = NULL;
 170         VALUE_PAIR *tmp = NULL;
 171         regex_t preg;
 172         regmatch_t pmatch;
 173         int cflags = 0;
 174         int err = 0;
 175         char done_xlat = 0;
 176         unsigned int len = 0;
 177         char err_msg[MAX_STRING_LEN];
 178         unsigned int i = 0;
 179         unsigned int counter = 0;
 180         char new_str[MAX_STRING_LEN];
 181         char *ptr, *ptr2;
 182         char search_STR[MAX_STRING_LEN];
 183         char replace_STR[MAX_STRING_LEN];
 184         int replace_len = 0;
 185
 186         if ((attr_vp = pairfind(request->config_items, PW_REWRITE_RULE)) != NULL){
 187                 if (data->name == NULL || strcmp(data->name,attr_vp->strvalue))
 188                         return RLM_MODULE_NOOP;
 189         }
 190
 191         if (!data->new_attr){
 192                 switch (data->searchin) {
 193                         case RLM_REGEX_INPACKET:
 194                                 if (data->attr_num == PW_USER_NAME)
 195                                         attr_vp = request->username;
 196                                 else if (data->attr_num == PW_PASSWORD)
 197                                         attr_vp = request->password;
 198                                 else
 199                                         tmp = request->packet->vps;
 200                                 break;
 201                         case RLM_REGEX_INCONFIG:
 202                                 tmp = request->config_items;
 203                                 break;
 204                         case RLM_REGEX_INREPLY:
 205                                 tmp = request->reply->vps;
 206                                 break;
 207                         case RLM_REGEX_INPROXY:
 208                                 tmp = request->proxy_reply->vps;
 209                                 break;
 210                         case RLM_REGEX_INPROXYREPLY:
 211                                 tmp = request->proxy->vps;
 212                                 break;
 213                         default:
 214                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 215                                 data->searchin = RLM_REGEX_INPACKET;
 216                                 attr_vp = pairfind(request->packet->vps, data->attr_num);
 217                                 break;
 218                 }
 219 do_again:
 220                 if (tmp != NULL)
 221                         attr_vp = pairfind(tmp, data->attr_num);
 222                 if (attr_vp == NULL) {
 223                         DEBUG2("rlm_attr_rewrite: Could not find value pair for attribute %s",data->attribute);
 224                         return ret;
 225                 }
 226                 if (attr_vp->strvalue == NULL || attr_vp->length == 0){
 227                         DEBUG2("rlm_attr_rewrite: Attribute %s string value NULL or of zero length",data->attribute);
 228                         return ret;
 229                 }
 230                 cflags |= REG_EXTENDED;
 231                 if (data->nocase)
 232                         cflags |= REG_ICASE;
 233
 234                 if (!radius_xlat(search_STR, sizeof(search_STR), data->search, request, NULL) && data->search_len != 0) {
 235                         DEBUG2("rlm_attr_rewrite: xlat on search string failed.");
 236                         return ret;
 237                 }
 238         }
 239         if (data->new_attr){
 240                 if (!radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL)) {
 241                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 242                         return ret;
 243                 }
 244                 replace_len = strlen(replace_STR);
 245         }
 246
 247         if (!data->new_attr){
 248                 if ((err = regcomp(&preg,search_STR,cflags))) {
 249                         regerror(err, &preg, err_msg, MAX_STRING_LEN);
 250                         DEBUG2("rlm_attr_rewrite: regcomp() returned error: %s",err_msg);
 251                         return ret;
 252                 }
 253                 ptr = new_str;
 254                 ptr2 = attr_vp->strvalue;
 255                 counter = 0;
 256
 257                 for ( i = 0 ;i < (unsigned)data->num_matches; i++) {
 258                         err = regexec(&preg, ptr2, 1, &pmatch, 0);
 259                         if (err == REG_NOMATCH) {
 260                                 if (i == 0) {
 261                                         DEBUG2("rlm_attr_rewrite: No match found for attribute %s with value '%s'",
 262                                                         data->attribute, attr_vp->strvalue);
 263                                         regfree(&preg);
 264                                         goto to_do_again;
 265                                 } else
 266                                         break;
 267                         }
 268                         if (err != 0) {
 269                                 regfree(&preg);
 270                                 radlog(L_ERR, "rlm_attr_rewrite: match failure for attribute %s with value '%s'",
 271                                                 data->attribute, attr_vp->strvalue);
 272                                 return ret;
 273                         }
 274                         if (pmatch.rm_so == -1)
 275                                 break;
 276                         len = pmatch.rm_so;
 277                         if (data->append) {
 278                                 len = len + (pmatch.rm_eo - pmatch.rm_so);
 279                         }
 280                         counter += len;
 281                         if (counter >= MAX_STRING_LEN) {
 282                                 regfree(&preg);
 283                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 284                                                 data->attribute, attr_vp->strvalue);
 285                                 return ret;
 286                         }
 287
 288                         strncpy(ptr, ptr2,len);
 289                         ptr += len;
 290                         ptr2 += pmatch.rm_eo;
 291
 292                         if (!done_xlat){
 293                                 if (data->replace_len != 0 &&
 294                                 radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL) == 0) {
 295                                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 296                                         return ret;
 297                                 }
 298                                 replace_len = (data->replace_len != 0) ? strlen(replace_STR) : 0;
 299                                 done_xlat = 1;
 300                         }
 301
 302                         counter += replace_len;
 303                         if (counter >= MAX_STRING_LEN) {
 304                                 regfree(&preg);
 305                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 306                                                 data->attribute, attr_vp->strvalue);
 307                                 return ret;
 308                         }
 309                         if (replace_len){
 310                                 strncpy(ptr, replace_STR, replace_len);
 311                                 ptr += replace_len;
 312                         }
 313                 }
 314                 regfree(&preg);
 315                 len = strlen(ptr2) + 1;         /* We add the ending NULL */
 316                 counter += len;
 317                 if (counter >= MAX_STRING_LEN){
 318                         DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 319                                         data->attribute, attr_vp->strvalue);
 320                         return ret;
 321                 }
 322                 strncpy(ptr, ptr2, len);
 323
 324                 DEBUG2("rlm_attr_rewrite: Changed value for attribute %s from '%s' to '%s'",
 325                                 data->attribute, attr_vp->strvalue, new_str);
 326                 attr_vp->length = strlen(new_str);
 327                 strncpy(attr_vp->strvalue, new_str, (attr_vp->length + 1));
 328
 329 to_do_again:
 330                 ret = RLM_MODULE_OK;
 331
 332                 if (tmp != NULL){
 333                         tmp = attr_vp->next;
 334                         if (tmp != NULL)
 335                                 goto do_again;
 336                 }
 337         }
 338         else{
 339                 attr_vp = pairmake(data->attribute,replace_STR,0);
 340                 switch(data->searchin){
 341                         case RLM_REGEX_INPACKET:
 342                                 pairadd(&request->packet->vps,attr_vp);
 343                                 break;
 344                         case RLM_REGEX_INCONFIG:
 345                                 pairadd(&request->config_items,attr_vp);
 346                                 break;
 347                         case RLM_REGEX_INREPLY:
 348                                 pairadd(&request->reply->vps,attr_vp);
 349                                 break;
 350                         default:
 351                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 352                                 data->searchin = RLM_REGEX_INPACKET;
 353                                 pairadd(&request->packet->vps,attr_vp);
 354                                 break;
 355                 }
 356                 DEBUG2("rlm_attr_rewrite: Added attribute %s with value '%s'",data->attribute,replace_STR);
 357                 ret = RLM_MODULE_OK;
 358         }
 359
 360
 361         return ret;
 362 }
 363
 364
 365 static int attr_rewrite_accounting(void *instance, REQUEST *request)
 366 {
 367         return do_attr_rewrite(instance, request);
 368 }
 369
 370 static int attr_rewrite_authorize(void *instance, REQUEST *request)
 371 {
 372         return do_attr_rewrite(instance, request);
 373 }
 374 static int attr_rewrite_authenticate(void *instance, REQUEST *request)
 375 {
 376         return do_attr_rewrite(instance, request);
 377 }
 378 static int attr_rewrite_preacct(void *instance, REQUEST *request)
 379 {
 380         return do_attr_rewrite(instance, request);
 381 }
 382 static int attr_rewrite_ismul(void *instance, REQUEST *request)
 383 {
 384         return do_attr_rewrite(instance, request);
 385 }
 386
 387 static int attr_rewrite_preproxy(void *instance, REQUEST *request)
 388 {
 389         return do_attr_rewrite(instance, request);
 390 }
 391
 392 static int attr_rewrite_postproxy(void *instance, REQUEST *request)
 393 {
 394         return do_attr_rewrite(instance, request);
 395 }
 396
 397 static int attr_rewrite_postauth(void *instance, REQUEST *request)
 398 {
 399         return do_attr_rewrite(instance, request);
 400 }
 401
 402 static int attr_rewrite_detach(void *instance)
 403 {
 404         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 405
 406         if (data->attribute)
 407                 free(data->attribute);
 408         if (data->search)
 409                 free(data->search);
 410         if (data->replace)
 411                 free(data->replace);
 412         if (data->name)
 413                 free(data->name);
 414
 415         free(instance);
 416         return 0;
 417 }
 418
 419 /*
 420  *      The module name should be the only globally exported symbol.
 421  *      That is, everything else should be 'static'.
 422  *
 423  *      If the module needs to temporarily modify it's instantiation
 424  *      data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 425  *      The server will then take care of ensuring that the module
 426  *      is single-threaded.
 427  */
 428 module_t rlm_attr_rewrite = {
 429         "attr_rewrite",
 430         RLM_TYPE_THREAD_UNSAFE,         /* type */
 431         NULL,                           /* initialization */
 432         attr_rewrite_instantiate,               /* instantiation */
 433         {
 434                 attr_rewrite_authenticate,      /* authentication */
 435                 attr_rewrite_authorize,         /* authorization */
 436                 attr_rewrite_preacct,           /* preaccounting */
 437                 attr_rewrite_accounting,        /* accounting */
 438                 attr_rewrite_ismul,             /* checksimul */
 439                 attr_rewrite_preproxy,          /* pre-proxy */
 440                 attr_rewrite_postproxy,         /* post-proxy */
 441                 attr_rewrite_postauth           /* post-auth */
 442         },
 443         attr_rewrite_detach,                    /* detach */
 444         NULL,                           /* destroy */
 445 };