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 #include "libradius.h"
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #ifdef HAVE_REGEX_H
  31 #       include <regex.h>
  32 #endif
  33
  34 #include "radiusd.h"
  35 #include "modules.h"
  36 #include "conffile.h"
  37
  38 #define RLM_REGEX_INPACKET 0
  39 #define RLM_REGEX_INCONFIG 1
  40 #define RLM_REGEX_INREPLY  2
  41 #define RLM_REGEX_INPROXY 3
  42 #define RLM_REGEX_INPROXYREPLY 4
  43
  44 static const char rcsid[] = "$Id$";
  45
  46 typedef struct rlm_attr_rewrite_t {
  47         char *attribute;        /* The attribute to search for */
  48         int  attr_num;          /* The attribute number */
  49         char *search;           /* The pattern to search for */
  50         int search_len;         /* The length of the search pattern */
  51         char *searchin_str;     /* The VALUE_PAIR list to search in. Can be either packet,reply,proxy,proxy_reply or config */
  52         char searchin;          /* The same as above just coded as a number for speed */
  53         char *replace;          /* The replacement */
  54         int replace_len;        /* The length of the replacement string */
  55         int  append;            /* Switch to control append mode (1,0) */
  56         int  nocase;            /* Ignore case */
  57         int  new_attr;          /* Boolean. Do we create a new attribute or not? */
  58         int  num_matches;       /* Maximum number of matches */
  59         char *name;             /* The module name */
  60 } rlm_attr_rewrite_t;
  61
  62
  63 static CONF_PARSER module_config[] = {
  64   { "attribute", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,attribute), NULL, NULL },
  65   { "searchfor", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,search), NULL, NULL },
  66   { "searchin",  PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,searchin_str), NULL, "packet" },
  67   { "replacewith", PW_TYPE_STRING_PTR, offsetof(rlm_attr_rewrite_t,replace), NULL, NULL },
  68   { "append", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,append),NULL, "no" },
  69   { "ignore_case", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,nocase), NULL, "yes" },
  70   { "new_attribute", PW_TYPE_BOOLEAN, offsetof(rlm_attr_rewrite_t,new_attr), NULL, "no" },
  71   { "max_matches", PW_TYPE_INTEGER, offsetof(rlm_attr_rewrite_t,num_matches), NULL, "10" },
  72   { NULL, -1, 0, NULL, NULL }
  73 };
  74
  75
  76 static int attr_rewrite_instantiate(CONF_SECTION *conf, void **instance)
  77 {
  78         rlm_attr_rewrite_t *data;
  79         DICT_ATTR *dattr;
  80         char *instance_name = NULL;
  81
  82         /*
  83          *      Set up a storage area for instance data
  84          */
  85         data = rad_malloc(sizeof(*data));
  86         if (!data) {
  87                 return -1;
  88         }
  89         memset(data, 0, sizeof(*data));
  90
  91         /*
  92          *      If the configuration parameters can't be parsed, then
  93          *      fail.
  94          */
  95         if (cf_section_parse(conf, data, module_config) < 0) {
  96                 free(data);
  97                 return -1;
  98         }
  99
 100         /*
 101          *      Discover the attribute number of the key.
 102          */
 103         if (data->attribute == NULL) {
 104                 radlog(L_ERR, "rlm_attr_rewrite: 'attribute' must be set.");
 105                 return -1;
 106         }
 107         if (data->search == NULL || data->replace == NULL) {
 108                 radlog(L_ERR, "rlm_attr_rewrite: search/replace strings must be set.");
 109                 return -1;
 110         }
 111         data->search_len = strlen(data->search);
 112         data->replace_len = strlen(data->replace);
 113
 114         if (data->replace_len == 0 && data->new_attr){
 115                 radlog(L_ERR, "rlm_attr_rewrite: replace string must not be zero length in order to create new attribute.");
 116                 return -1;
 117         }
 118
 119         if (data->num_matches < 1 || data->num_matches > MAX_STRING_LEN) {
 120                 radlog(L_ERR, "rlm_attr_rewrite: Illegal range for match number.");
 121                 return -1;
 122         }
 123         if (data->searchin_str == NULL) {
 124                 radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 125                 data->searchin = RLM_REGEX_INPACKET;
 126         }
 127         else{
 128                 if (strcmp(data->searchin_str, "packet") == 0)
 129                         data->searchin = RLM_REGEX_INPACKET;
 130                 else if (strcmp(data->searchin_str, "config") == 0)
 131                         data->searchin = RLM_REGEX_INCONFIG;
 132                 else if (strcmp(data->searchin_str, "reply") == 0)
 133                         data->searchin = RLM_REGEX_INREPLY;
 134                 else if (strcmp(data->searchin_str, "proxy") == 0)
 135                         data->searchin = RLM_REGEX_INPROXY;
 136                 else if (strcmp(data->searchin_str, "proxy_reply") == 0)
 137                         data->searchin = RLM_REGEX_INPROXYREPLY;
 138                 else {
 139                         radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 140                         data->searchin = RLM_REGEX_INPACKET;
 141                 }
 142                 free((char *)data->searchin_str);
 143         }
 144         dattr = dict_attrbyname(data->attribute);
 145         if (dattr == NULL) {
 146                 radlog(L_ERR, "rlm_attr_rewrite: No such attribute %s",
 147                                 data->attribute);
 148                 return -1;
 149         }
 150         data->attr_num = dattr->attr;
 151         /* Add the module instance name */
 152         data->name = NULL;
 153         instance_name = cf_section_name2(conf);
 154         if (instance_name != NULL)
 155                 data->name = strdup(instance_name);
 156
 157
 158         *instance = data;
 159
 160         return 0;
 161 }
 162
 163 static int do_attr_rewrite(void *instance, REQUEST *request)
 164 {
 165         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 166         int ret = RLM_MODULE_NOOP;
 167         VALUE_PAIR *attr_vp = NULL;
 168         VALUE_PAIR *tmp = NULL;
 169         regex_t preg;
 170         regmatch_t pmatch[9];
 171         int cflags = 0;
 172         int err = 0;
 173         char done_xlat = 0;
 174         unsigned int len = 0;
 175         char err_msg[MAX_STRING_LEN];
 176         unsigned int i = 0;
 177         unsigned int j = 0;
 178         unsigned int counter = 0;
 179         char new_str[MAX_STRING_LEN];
 180         char *ptr, *ptr2;
 181         char search_STR[MAX_STRING_LEN];
 182         char replace_STR[MAX_STRING_LEN];
 183         int replace_len = 0;
 184
 185         if ((attr_vp = pairfind(request->config_items, PW_REWRITE_RULE)) != NULL){
 186                 if (data->name == NULL || strcmp(data->name,attr_vp->strvalue))
 187                         return RLM_MODULE_NOOP;
 188         }
 189
 190         if (data->new_attr){
 191                 /* new_attribute = yes */
 192                 if (!radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL)) {
 193                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 194                         return ret;
 195                 }
 196                 replace_len = strlen(replace_STR);
 197                 attr_vp = pairmake(data->attribute,replace_STR,0);
 198                 if (attr_vp == NULL){
 199                         DEBUG2("rlm_attr_rewrite: Could not add new attribute %s with value '%s'",
 200                                 data->attribute,replace_STR);
 201                         return ret;
 202                 }
 203                 switch(data->searchin){
 204                         case RLM_REGEX_INPACKET:
 205                                 pairadd(&request->packet->vps,attr_vp);
 206                                 break;
 207                         case RLM_REGEX_INCONFIG:
 208                                 pairadd(&request->config_items,attr_vp);
 209                                 break;
 210                         case RLM_REGEX_INREPLY:
 211                                 pairadd(&request->reply->vps,attr_vp);
 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                                 pairadd(&request->packet->vps,attr_vp);
 217                                 break;
 218                 }
 219                 DEBUG2("rlm_attr_rewrite: Added attribute %s with value '%s'",data->attribute,replace_STR);
 220                 ret = RLM_MODULE_OK;
 221         } else {
 222                 /* new_attribute = no */
 223                 switch (data->searchin) {
 224                         case RLM_REGEX_INPACKET:
 225                                 if (data->attr_num == PW_USER_NAME)
 226                                         attr_vp = request->username;
 227                                 else if (data->attr_num == PW_PASSWORD)
 228                                         attr_vp = request->password;
 229                                 else
 230                                         tmp = request->packet->vps;
 231                                 break;
 232                         case RLM_REGEX_INCONFIG:
 233                                 tmp = request->config_items;
 234                                 break;
 235                         case RLM_REGEX_INREPLY:
 236                                 tmp = request->reply->vps;
 237                                 break;
 238                         case RLM_REGEX_INPROXYREPLY:
 239                                 if (!request->proxy_reply)
 240                                         return RLM_MODULE_NOOP;
 241                                 tmp = request->proxy_reply->vps;
 242                                 break;
 243                         case RLM_REGEX_INPROXY:
 244                                 if (!request->proxy)
 245                                         return RLM_MODULE_NOOP;
 246                                 tmp = request->proxy->vps;
 247                                 break;
 248                         default:
 249                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 250                                 data->searchin = RLM_REGEX_INPACKET;
 251                                 attr_vp = pairfind(request->packet->vps, data->attr_num);
 252                                 break;
 253                 }
 254 do_again:
 255                 if (tmp != NULL)
 256                         attr_vp = pairfind(tmp, data->attr_num);
 257                 if (attr_vp == NULL) {
 258                         DEBUG2("rlm_attr_rewrite: Could not find value pair for attribute %s",data->attribute);
 259                         return ret;
 260                 }
 261                 if (attr_vp->strvalue == NULL || attr_vp->length == 0){
 262                         DEBUG2("rlm_attr_rewrite: Attribute %s string value NULL or of zero length",data->attribute);
 263                         return ret;
 264                 }
 265                 cflags |= REG_EXTENDED;
 266                 if (data->nocase)
 267                         cflags |= REG_ICASE;
 268
 269                 if (!radius_xlat(search_STR, sizeof(search_STR), data->search, request, NULL) && data->search_len != 0) {
 270                         DEBUG2("rlm_attr_rewrite: xlat on search string failed.");
 271                         return ret;
 272                 }
 273
 274                 if ((err = regcomp(&preg,search_STR,cflags))) {
 275                         regerror(err, &preg, err_msg, MAX_STRING_LEN);
 276                         DEBUG2("rlm_attr_rewrite: regcomp() returned error: %s",err_msg);
 277                         return ret;
 278                 }
 279                 ptr = new_str;
 280                 ptr2 = attr_vp->strvalue;
 281                 counter = 0;
 282
 283                 for ( i = 0 ;i < (unsigned)data->num_matches; i++) {
 284                         err = regexec(&preg, ptr2, 9, pmatch, 0);
 285                         if (err == REG_NOMATCH) {
 286                                 if (i == 0) {
 287                                         DEBUG2("rlm_attr_rewrite: No match found for attribute %s with value '%s'",
 288                                                         data->attribute, attr_vp->strvalue);
 289                                         regfree(&preg);
 290                                         goto to_do_again;
 291                                 } else
 292                                         break;
 293                         }
 294                         if (err != 0) {
 295                                 regfree(&preg);
 296                                 radlog(L_ERR, "rlm_attr_rewrite: match failure for attribute %s with value '%s'",
 297                                                 data->attribute, attr_vp->strvalue);
 298                                 return ret;
 299                         }
 300                         if (pmatch[0].rm_so == -1)
 301                                 break;
 302                         len = pmatch[0].rm_so;
 303                         if (data->append) {
 304                                 len = len + (pmatch[0].rm_eo - pmatch[0].rm_so);
 305                         }
 306                         counter += len;
 307                         if (counter >= MAX_STRING_LEN) {
 308                                 regfree(&preg);
 309                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 310                                                 data->attribute, attr_vp->strvalue);
 311                                 return ret;
 312                         }
 313
 314                         strncpy(ptr, ptr2,len);
 315                         ptr += len;
 316                         ptr2 += pmatch[0].rm_eo;
 317
 318                         if (i == 0){
 319                                 /*
 320                                  * We only run on the first match, sorry
 321                                  */
 322                                 for(j = 0; j <= 8; j++){
 323                                         char *p;
 324                                         char buffer[sizeof(attr_vp->strvalue)];
 325
 326                                         /*
 327                                          * Stolen from src/main/valuepair.c, paircmp()
 328                                          */
 329
 330                                         /*
 331                                          * Delete old matches if the corresponding match does not
 332                                          * exist in the current regex
 333                                          */
 334                                         if (pmatch[j].rm_so == -1){
 335                                                 p = request_data_get(request,request,REQUEST_DATA_REGEX | j);
 336                                                 if (p){
 337                                                         free(p);
 338                                                         continue;
 339                                                 }
 340                                                 break;
 341                                         }
 342                                         memcpy(buffer,
 343                                                 attr_vp->strvalue + pmatch[j].rm_so,pmatch[j].rm_eo);
 344                                         buffer[pmatch[j].rm_eo] = '\0';
 345                                         p = strdup(buffer);
 346                                         request_data_add(request,request,REQUEST_DATA_REGEX | j,p,free);
 347                                 }
 348                         }
 349
 350                         if (!done_xlat){
 351                                 if (data->replace_len != 0 &&
 352                                 radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL) == 0) {
 353                                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 354                                         return ret;
 355                                 }
 356                                 replace_len = (data->replace_len != 0) ? strlen(replace_STR) : 0;
 357                                 done_xlat = 1;
 358                         }
 359
 360                         counter += replace_len;
 361                         if (counter >= MAX_STRING_LEN) {
 362                                 regfree(&preg);
 363                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 364                                                 data->attribute, attr_vp->strvalue);
 365                                 return ret;
 366                         }
 367                         if (replace_len){
 368                                 strncpy(ptr, replace_STR, replace_len);
 369                                 ptr += replace_len;
 370                         }
 371                 }
 372                 regfree(&preg);
 373                 len = strlen(ptr2) + 1;         /* We add the ending NULL */
 374                 counter += len;
 375                 if (counter >= MAX_STRING_LEN){
 376                         DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 377                                         data->attribute, attr_vp->strvalue);
 378                         return ret;
 379                 }
 380                 strncpy(ptr, ptr2, len);
 381
 382                 DEBUG2("rlm_attr_rewrite: Changed value for attribute %s from '%s' to '%s'",
 383                                 data->attribute, attr_vp->strvalue, new_str);
 384                 attr_vp->length = strlen(new_str);
 385                 strncpy(attr_vp->strvalue, new_str, (attr_vp->length + 1));
 386
 387 to_do_again:
 388                 ret = RLM_MODULE_OK;
 389
 390                 if (tmp != NULL){
 391                         tmp = attr_vp->next;
 392                         if (tmp != NULL)
 393                                 goto do_again;
 394                 }
 395         }
 396
 397         return ret;
 398 }
 399
 400
 401 static int attr_rewrite_accounting(void *instance, REQUEST *request)
 402 {
 403         return do_attr_rewrite(instance, request);
 404 }
 405
 406 static int attr_rewrite_authorize(void *instance, REQUEST *request)
 407 {
 408         return do_attr_rewrite(instance, request);
 409 }
 410 static int attr_rewrite_authenticate(void *instance, REQUEST *request)
 411 {
 412         return do_attr_rewrite(instance, request);
 413 }
 414 static int attr_rewrite_preacct(void *instance, REQUEST *request)
 415 {
 416         return do_attr_rewrite(instance, request);
 417 }
 418 static int attr_rewrite_ismul(void *instance, REQUEST *request)
 419 {
 420         return do_attr_rewrite(instance, request);
 421 }
 422
 423 static int attr_rewrite_preproxy(void *instance, REQUEST *request)
 424 {
 425         return do_attr_rewrite(instance, request);
 426 }
 427
 428 static int attr_rewrite_postproxy(void *instance, REQUEST *request)
 429 {
 430         return do_attr_rewrite(instance, request);
 431 }
 432
 433 static int attr_rewrite_postauth(void *instance, REQUEST *request)
 434 {
 435         return do_attr_rewrite(instance, request);
 436 }
 437
 438 static int attr_rewrite_detach(void *instance)
 439 {
 440         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 441
 442         if (data->attribute)
 443                 free(data->attribute);
 444         if (data->search)
 445                 free(data->search);
 446         if (data->replace)
 447                 free(data->replace);
 448         if (data->name)
 449                 free(data->name);
 450
 451         free(instance);
 452         return 0;
 453 }
 454
 455 /*
 456  *      The module name should be the only globally exported symbol.
 457  *      That is, everything else should be 'static'.
 458  *
 459  *      If the module needs to temporarily modify it's instantiation
 460  *      data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 461  *      The server will then take care of ensuring that the module
 462  *      is single-threaded.
 463  */
 464 module_t rlm_attr_rewrite = {
 465         "attr_rewrite",
 466         RLM_TYPE_THREAD_UNSAFE,         /* type */
 467         NULL,                           /* initialization */
 468         attr_rewrite_instantiate,               /* instantiation */
 469         {
 470                 attr_rewrite_authenticate,      /* authentication */
 471                 attr_rewrite_authorize,         /* authorization */
 472                 attr_rewrite_preacct,           /* preaccounting */
 473                 attr_rewrite_accounting,        /* accounting */
 474                 attr_rewrite_ismul,             /* checksimul */
 475                 attr_rewrite_preproxy,          /* pre-proxy */
 476                 attr_rewrite_postproxy,         /* post-proxy */
 477                 attr_rewrite_postauth           /* post-auth */
 478         },
 479         attr_rewrite_detach,                    /* detach */
 480         NULL,                           /* destroy */
 481 };