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 "autoconf.h"
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #ifdef HAVE_REGEX_H
  30 #       include <regex.h>
  31 #endif
  32
  33 #include "radiusd.h"
  34 #include "modules.h"
  35 #include "conffile.h"
  36
  37 #define RLM_REGEX_INPACKET 0
  38 #define RLM_REGEX_INCONFIG 1
  39 #define RLM_REGEX_INREPLY  2
  40 #define RLM_REGEX_INPROXY 3
  41 #define RLM_REGEX_INPROXYREPLY 4
  42
  43 static const char rcsid[] = "$Id$";
  44
  45 typedef struct rlm_attr_rewrite_t {
  46         char *attribute;        /* The attribute to search for */
  47         int  attr_num;          /* The attribute number */
  48         char *search;           /* The pattern to search for */
  49         int search_len;         /* The length of the search pattern */
  50         char *searchin_str;     /* The VALUE_PAIR list to search in. Can be either packet,reply,proxy,proxy_reply or config */
  51         char searchin;          /* The same as above just coded as a number for speed */
  52         char *replace;          /* The replacement */
  53         int replace_len;        /* The length of the replacement string */
  54         int  append;            /* Switch to control append mode (1,0) */
  55         int  nocase;            /* Ignore case */
  56         int  new_attr;          /* Boolean. Do we create a new attribute or not? */
  57         int  num_matches;       /* Maximum number of matches */
  58         char *name;             /* The module name */
  59 } rlm_attr_rewrite_t;
  60
  61
  62 static const CONF_PARSER module_config[] = {
  63   { "attribute", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,attribute), NULL, NULL },
  64   { "searchfor", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,search), NULL, NULL },
  65   { "searchin",  PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,searchin_str), NULL, "packet" },
  66   { "replacewith", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,replace), NULL, NULL },
  67   { "append", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,append),NULL, "no" },
  68   { "ignore_case", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,nocase), NULL, "yes" },
  69   { "new_attribute", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,new_attr), NULL, "no" },
  70   { "max_matches", PW_TYPE_INTEGER, offsetof(rlm_attr_rewrite_t,num_matches), NULL, "10" },
  71   { NULL, -1, 0, NULL, NULL }
  72 };
  73
  74
  75 static int attr_rewrite_instantiate(CONF_SECTION *conf, void **instance)
  76 {
  77         rlm_attr_rewrite_t *data;
  78         DICT_ATTR *dattr;
  79         char *instance_name = NULL;
  80
  81         /*
  82          *      Set up a storage area for instance data
  83          */
  84         data = rad_malloc(sizeof(*data));
  85         if (!data) {
  86                 return -1;
  87         }
  88         memset(data, 0, sizeof(*data));
  89
  90         /*
  91          *      If the configuration parameters can't be parsed, then
  92          *      fail.
  93          */
  94         if (cf_section_parse(conf, data, module_config) < 0) {
  95                 free(data);
  96                 return -1;
  97         }
  98
  99         /*
 100          *      Discover the attribute number of the key.
 101          */
 102         if (data->attribute == NULL) {
 103                 radlog(L_ERR, "rlm_attr_rewrite: 'attribute' must be set.");
 104                 return -1;
 105         }
 106         if (data->search == NULL || data->replace == NULL) {
 107                 radlog(L_ERR, "rlm_attr_rewrite: search/replace strings must be set.");
 108                 return -1;
 109         }
 110         data->search_len = strlen(data->search);
 111         data->replace_len = strlen(data->replace);
 112
 113         if (data->replace_len == 0 && data->new_attr){
 114                 radlog(L_ERR, "rlm_attr_rewrite: replace string must not be zero length in order to create new attribute.");
 115                 return -1;
 116         }
 117
 118         if (data->num_matches < 1 || data->num_matches > MAX_STRING_LEN) {
 119                 radlog(L_ERR, "rlm_attr_rewrite: Illegal range for match number.");
 120                 return -1;
 121         }
 122         if (data->searchin_str == NULL) {
 123                 radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 124                 data->searchin = RLM_REGEX_INPACKET;
 125         }
 126         else{
 127                 if (strcmp(data->searchin_str, "packet") == 0)
 128                         data->searchin = RLM_REGEX_INPACKET;
 129                 else if (strcmp(data->searchin_str, "config") == 0)
 130                         data->searchin = RLM_REGEX_INCONFIG;
 131                 else if (strcmp(data->searchin_str, "reply") == 0)
 132                         data->searchin = RLM_REGEX_INREPLY;
 133                 else if (strcmp(data->searchin_str, "proxy") == 0)
 134                         data->searchin = RLM_REGEX_INPROXY;
 135                 else if (strcmp(data->searchin_str, "proxy_reply") == 0)
 136                         data->searchin = RLM_REGEX_INPROXYREPLY;
 137                 else {
 138                         radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 139                         data->searchin = RLM_REGEX_INPACKET;
 140                 }
 141                 free((char *)data->searchin_str);
 142         }
 143         dattr = dict_attrbyname(data->attribute);
 144         if (dattr == NULL) {
 145                 radlog(L_ERR, "rlm_attr_rewrite: No such attribute %s",
 146                                 data->attribute);
 147                 return -1;
 148         }
 149         data->attr_num = dattr->attr;
 150         /* Add the module instance name */
 151         data->name = NULL;
 152         instance_name = cf_section_name2(conf);
 153         if (instance_name != NULL)
 154                 data->name = strdup(instance_name);
 155
 156
 157         *instance = data;
 158
 159         return 0;
 160 }
 161
 162 static int do_attr_rewrite(void *instance, REQUEST *request)
 163 {
 164         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 165         int ret = RLM_MODULE_NOOP;
 166         VALUE_PAIR *attr_vp = NULL;
 167         VALUE_PAIR *tmp = NULL;
 168         regex_t preg;
 169         regmatch_t pmatch[9];
 170         int cflags = 0;
 171         int err = 0;
 172         char done_xlat = 0;
 173         unsigned int len = 0;
 174         char err_msg[MAX_STRING_LEN];
 175         unsigned int i = 0;
 176         unsigned int j = 0;
 177         unsigned int counter = 0;
 178         char new_str[MAX_STRING_LEN];
 179         char *ptr, *ptr2;
 180         char search_STR[MAX_STRING_LEN];
 181         char replace_STR[MAX_STRING_LEN];
 182         int replace_len = 0;
 183
 184         if ((attr_vp = pairfind(request->config_items, PW_REWRITE_RULE)) != NULL){
 185                 if (data->name == NULL || strcmp(data->name,attr_vp->strvalue))
 186                         return RLM_MODULE_NOOP;
 187         }
 188
 189         if (data->new_attr){
 190                 /* new_attribute = yes */
 191                 if (!radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL)) {
 192                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 193                         return ret;
 194                 }
 195                 replace_len = strlen(replace_STR);
 196                 attr_vp = pairmake(data->attribute,replace_STR,0);
 197                 if (attr_vp == NULL){
 198                         DEBUG2("rlm_attr_rewrite: Could not add new attribute %s with value '%s'",
 199                                 data->attribute,replace_STR);
 200                         return ret;
 201                 }
 202                 switch(data->searchin){
 203                         case RLM_REGEX_INPACKET:
 204                                 pairadd(&request->packet->vps,attr_vp);
 205                                 break;
 206                         case RLM_REGEX_INCONFIG:
 207                                 pairadd(&request->config_items,attr_vp);
 208                                 break;
 209                         case RLM_REGEX_INREPLY:
 210                                 pairadd(&request->reply->vps,attr_vp);
 211                                 break;
 212                         case RLM_REGEX_INPROXY:
 213                                 if (!request->proxy) {
 214                                         pairbasicfree(attr_vp);
 215                                         return RLM_MODULE_NOOP;
 216                                 }
 217                                 pairadd(&request->proxy->vps, attr_vp);
 218                                 break;
 219                         case RLM_REGEX_INPROXYREPLY:
 220                                 if (!request->proxy_reply) {
 221                                         pairbasicfree(attr_vp);
 222                                         return RLM_MODULE_NOOP;
 223                                 }
 224                                 pairadd(&request->proxy_reply->vps, attr_vp);
 225                                 break;
 226                         default:
 227                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 228                                 data->searchin = RLM_REGEX_INPACKET;
 229                                 pairadd(&request->packet->vps,attr_vp);
 230                                 break;
 231                 }
 232                 DEBUG2("rlm_attr_rewrite: Added attribute %s with value '%s'",data->attribute,replace_STR);
 233                 ret = RLM_MODULE_OK;
 234         } else {
 235                 /* new_attribute = no */
 236                 switch (data->searchin) {
 237                         case RLM_REGEX_INPACKET:
 238                                 if (data->attr_num == PW_USER_NAME)
 239                                         attr_vp = request->username;
 240                                 else if (data->attr_num == PW_PASSWORD)
 241                                         attr_vp = request->password;
 242                                 else
 243                                         tmp = request->packet->vps;
 244                                 break;
 245                         case RLM_REGEX_INCONFIG:
 246                                 tmp = request->config_items;
 247                                 break;
 248                         case RLM_REGEX_INREPLY:
 249                                 tmp = request->reply->vps;
 250                                 break;
 251                         case RLM_REGEX_INPROXYREPLY:
 252                                 if (!request->proxy_reply)
 253                                         return RLM_MODULE_NOOP;
 254                                 tmp = request->proxy_reply->vps;
 255                                 break;
 256                         case RLM_REGEX_INPROXY:
 257                                 if (!request->proxy)
 258                                         return RLM_MODULE_NOOP;
 259                                 tmp = request->proxy->vps;
 260                                 break;
 261                         default:
 262                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 263                                 data->searchin = RLM_REGEX_INPACKET;
 264                                 attr_vp = pairfind(request->packet->vps, data->attr_num);
 265                                 break;
 266                 }
 267 do_again:
 268                 if (tmp != NULL)
 269                         attr_vp = pairfind(tmp, data->attr_num);
 270                 if (attr_vp == NULL) {
 271                         DEBUG2("rlm_attr_rewrite: Could not find value pair for attribute %s",data->attribute);
 272                         return ret;
 273                 }
 274                 if (attr_vp->strvalue == NULL || attr_vp->length == 0){
 275                         DEBUG2("rlm_attr_rewrite: Attribute %s string value NULL or of zero length",data->attribute);
 276                         return ret;
 277                 }
 278                 cflags |= REG_EXTENDED;
 279                 if (data->nocase)
 280                         cflags |= REG_ICASE;
 281
 282                 if (!radius_xlat(search_STR, sizeof(search_STR), data->search, request, NULL) && data->search_len != 0) {
 283                         DEBUG2("rlm_attr_rewrite: xlat on search string failed.");
 284                         return ret;
 285                 }
 286
 287                 if ((err = regcomp(&preg,search_STR,cflags))) {
 288                         regerror(err, &preg, err_msg, MAX_STRING_LEN);
 289                         DEBUG2("rlm_attr_rewrite: regcomp() returned error: %s",err_msg);
 290                         return ret;
 291                 }
 292                 ptr = new_str;
 293                 ptr2 = attr_vp->strvalue;
 294                 counter = 0;
 295
 296                 for ( i = 0 ;i < (unsigned)data->num_matches; i++) {
 297                         err = regexec(&preg, ptr2, REQUEST_MAX_REGEX, pmatch, 0);
 298                         if (err == REG_NOMATCH) {
 299                                 if (i == 0) {
 300                                         DEBUG2("rlm_attr_rewrite: No match found for attribute %s with value '%s'",
 301                                                         data->attribute, attr_vp->strvalue);
 302                                         regfree(&preg);
 303                                         goto to_do_again;
 304                                 } else
 305                                         break;
 306                         }
 307                         if (err != 0) {
 308                                 regfree(&preg);
 309                                 radlog(L_ERR, "rlm_attr_rewrite: match failure for attribute %s with value '%s'",
 310                                                 data->attribute, attr_vp->strvalue);
 311                                 return ret;
 312                         }
 313                         if (pmatch[0].rm_so == -1)
 314                                 break;
 315                         len = pmatch[0].rm_so;
 316                         if (data->append) {
 317                                 len = len + (pmatch[0].rm_eo - pmatch[0].rm_so);
 318                         }
 319                         counter += len;
 320                         if (counter >= MAX_STRING_LEN) {
 321                                 regfree(&preg);
 322                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 323                                                 data->attribute, attr_vp->strvalue);
 324                                 return ret;
 325                         }
 326
 327                         strncpy(ptr, ptr2,len);
 328                         ptr += len;
 329                         ptr2 += pmatch[0].rm_eo;
 330
 331                         if (i == 0){
 332                                 /*
 333                                  * We only run on the first match, sorry
 334                                  */
 335                                 for(j = 0; j <= REQUEST_MAX_REGEX; j++){
 336                                         char *p;
 337                                         char buffer[sizeof(attr_vp->strvalue)];
 338
 339                                         /*
 340                                          * Stolen from src/main/valuepair.c, paircmp()
 341                                          */
 342
 343                                         /*
 344                                          * Delete old matches if the corresponding match does not
 345                                          * exist in the current regex
 346                                          */
 347                                         if (pmatch[j].rm_so == -1){
 348                                                 p = request_data_get(request,request,REQUEST_DATA_REGEX | j);
 349                                                 if (p){
 350                                                         free(p);
 351                                                         continue;
 352                                                 }
 353                                                 break;
 354                                         }
 355                                         memcpy(buffer,
 356                                                attr_vp->strvalue + pmatch[j].rm_so,
 357                                                pmatch[j].rm_eo - pmatch[j].rm_so);
 358                                         buffer[pmatch[j].rm_eo - pmatch[j].rm_so] = '\0';
 359                                         p = strdup(buffer);
 360                                         request_data_add(request,request,REQUEST_DATA_REGEX | j,p,free);
 361                                 }
 362                         }
 363
 364                         if (!done_xlat){
 365                                 if (data->replace_len != 0 &&
 366                                 radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL) == 0) {
 367                                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 368                                         return ret;
 369                                 }
 370                                 replace_len = (data->replace_len != 0) ? strlen(replace_STR) : 0;
 371                                 done_xlat = 1;
 372                         }
 373
 374                         counter += replace_len;
 375                         if (counter >= MAX_STRING_LEN) {
 376                                 regfree(&preg);
 377                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 378                                                 data->attribute, attr_vp->strvalue);
 379                                 return ret;
 380                         }
 381                         if (replace_len){
 382                                 strncpy(ptr, replace_STR, replace_len);
 383                                 ptr += replace_len;
 384                         }
 385                 }
 386                 regfree(&preg);
 387                 len = strlen(ptr2) + 1;         /* We add the ending NULL */
 388                 counter += len;
 389                 if (counter >= MAX_STRING_LEN){
 390                         DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 391                                         data->attribute, attr_vp->strvalue);
 392                         return ret;
 393                 }
 394                 strncpy(ptr, ptr2, len);
 395
 396                 DEBUG2("rlm_attr_rewrite: Changed value for attribute %s from '%s' to '%s'",
 397                                 data->attribute, attr_vp->strvalue, new_str);
 398                 if (pairparsevalue(attr_vp, new_str) == NULL) {
 399                         DEBUG2("rlm_attr_rewrite: Could not write value '%s' into attribute %s: %s", new_str, data->attribute, librad_errstr);
 400                         return ret;
 401                 }
 402
 403 to_do_again:
 404                 ret = RLM_MODULE_OK;
 405
 406                 if (tmp != NULL){
 407                         tmp = attr_vp->next;
 408                         if (tmp != NULL)
 409                                 goto do_again;
 410                 }
 411         }
 412
 413         return ret;
 414 }
 415
 416
 417 static int attr_rewrite_accounting(void *instance, REQUEST *request)
 418 {
 419         return do_attr_rewrite(instance, request);
 420 }
 421
 422 static int attr_rewrite_authorize(void *instance, REQUEST *request)
 423 {
 424         return do_attr_rewrite(instance, request);
 425 }
 426 static int attr_rewrite_authenticate(void *instance, REQUEST *request)
 427 {
 428         return do_attr_rewrite(instance, request);
 429 }
 430 static int attr_rewrite_preacct(void *instance, REQUEST *request)
 431 {
 432         return do_attr_rewrite(instance, request);
 433 }
 434 static int attr_rewrite_ismul(void *instance, REQUEST *request)
 435 {
 436         return do_attr_rewrite(instance, request);
 437 }
 438
 439 static int attr_rewrite_preproxy(void *instance, REQUEST *request)
 440 {
 441         return do_attr_rewrite(instance, request);
 442 }
 443
 444 static int attr_rewrite_postproxy(void *instance, REQUEST *request)
 445 {
 446         return do_attr_rewrite(instance, request);
 447 }
 448
 449 static int attr_rewrite_postauth(void *instance, REQUEST *request)
 450 {
 451         return do_attr_rewrite(instance, request);
 452 }
 453
 454 static int attr_rewrite_detach(void *instance)
 455 {
 456         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 457
 458         if (data->attribute)
 459                 free(data->attribute);
 460         if (data->search)
 461                 free(data->search);
 462         if (data->replace)
 463                 free(data->replace);
 464         if (data->name)
 465                 free(data->name);
 466
 467         free(instance);
 468         return 0;
 469 }
 470
 471 /*
 472  *      The module name should be the only globally exported symbol.
 473  *      That is, everything else should be 'static'.
 474  *
 475  *      If the module needs to temporarily modify it's instantiation
 476  *      data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 477  *      The server will then take care of ensuring that the module
 478  *      is single-threaded.
 479  */
 480 module_t rlm_attr_rewrite = {
 481         "attr_rewrite",
 482         RLM_TYPE_THREAD_UNSAFE,         /* type */
 483         NULL,                           /* initialization */
 484         attr_rewrite_instantiate,               /* instantiation */
 485         {
 486                 attr_rewrite_authenticate,      /* authentication */
 487                 attr_rewrite_authorize,         /* authorization */
 488                 attr_rewrite_preacct,           /* preaccounting */
 489                 attr_rewrite_accounting,        /* accounting */
 490                 attr_rewrite_ismul,             /* checksimul */
 491                 attr_rewrite_preproxy,          /* pre-proxy */
 492                 attr_rewrite_postproxy,         /* post-proxy */
 493                 attr_rewrite_postauth           /* post-auth */
 494         },
 495         attr_rewrite_detach,                    /* detach */
 496         NULL,                           /* destroy */
 497 };