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
  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 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 {
 135                         radlog(L_ERR, "rlm_attr_rewrite: Illegal searchin directive given. Assuming packet.");
 136                         data->searchin = RLM_REGEX_INPACKET;
 137                 }
 138                 free((char *)data->searchin_str);
 139         }
 140         dattr = dict_attrbyname(data->attribute);
 141         if (dattr == NULL) {
 142                 radlog(L_ERR, "rlm_attr_rewrite: No such attribute %s",
 143                                 data->attribute);
 144                 return -1;
 145         }
 146         data->attr_num = dattr->attr;
 147         /* Add the module instance name */
 148         data->name = NULL;
 149         instance_name = cf_section_name2(conf);
 150         if (instance_name != NULL)
 151                 data->name = strdup(instance_name);
 152
 153
 154         *instance = data;
 155
 156         return 0;
 157 }
 158
 159 static int do_attr_rewrite(void *instance, REQUEST *request)
 160 {
 161         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 162         int ret = RLM_MODULE_NOOP;
 163         VALUE_PAIR *attr_vp = NULL;
 164         VALUE_PAIR *tmp = NULL;
 165         regex_t preg;
 166         regmatch_t pmatch;
 167         int cflags = 0;
 168         int err = 0;
 169         char done_xlat = 0;
 170         unsigned int len = 0;
 171         char err_msg[MAX_STRING_LEN];
 172         unsigned int i = 0;
 173         unsigned int counter = 0;
 174         char new_str[MAX_STRING_LEN];
 175         char *ptr, *ptr2;
 176         char search_STR[MAX_STRING_LEN];
 177         char replace_STR[MAX_STRING_LEN];
 178         int replace_len = 0;
 179
 180         if ((attr_vp = pairfind(request->config_items, PW_REWRITE_RULE)) != NULL){
 181                 if (data->name == NULL || strcmp(data->name,attr_vp->strvalue))
 182                         return RLM_MODULE_NOOP;
 183         }
 184
 185         if (!data->new_attr){
 186                 switch (data->searchin) {
 187                         case RLM_REGEX_INPACKET:
 188                                 if (data->attr_num == PW_USER_NAME)
 189                                         attr_vp = request->username;
 190                                 else if (data->attr_num == PW_PASSWORD)
 191                                         attr_vp = request->password;
 192                                 else
 193                                         tmp = request->packet->vps;
 194                                 break;
 195                         case RLM_REGEX_INCONFIG:
 196                                 tmp = request->config_items;
 197                                 break;
 198                         case RLM_REGEX_INREPLY:
 199                                 tmp = request->reply->vps;
 200                                 break;
 201                         default:
 202                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 203                                 data->searchin = RLM_REGEX_INPACKET;
 204                                 attr_vp = pairfind(request->packet->vps, data->attr_num);
 205                                 break;
 206                 }
 207 do_again:
 208                 if (tmp != NULL)
 209                         attr_vp = pairfind(tmp, data->attr_num);
 210                 if (attr_vp == NULL) {
 211                         DEBUG2("rlm_attr_rewrite: Could not find value pair for attribute %s",data->attribute);
 212                         return ret;
 213                 }
 214                 if (attr_vp->strvalue == NULL || attr_vp->length == 0){
 215                         DEBUG2("rlm_attr_rewrite: Attribute %s string value NULL or of zero length",data->attribute);
 216                         return ret;
 217                 }
 218                 cflags |= REG_EXTENDED;
 219                 if (data->nocase)
 220                         cflags |= REG_ICASE;
 221
 222                 if (!radius_xlat(search_STR, sizeof(search_STR), data->search, request, NULL) && data->search_len != 0) {
 223                         DEBUG2("rlm_attr_rewrite: xlat on search string failed.");
 224                         return ret;
 225                 }
 226         }
 227         if (data->new_attr){
 228                 if (!radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL)) {
 229                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 230                         return ret;
 231                 }
 232                 replace_len = strlen(replace_STR);
 233         }
 234
 235         if (!data->new_attr){
 236                 if ((err = regcomp(&preg,search_STR,cflags))) {
 237                         regerror(err, &preg, err_msg, MAX_STRING_LEN);
 238                         DEBUG2("rlm_attr_rewrite: regcomp() returned error: %s",err_msg);
 239                         return ret;
 240                 }
 241                 ptr = new_str;
 242                 ptr2 = attr_vp->strvalue;
 243                 counter = 0;
 244
 245                 for ( i = 0 ;i < (unsigned)data->num_matches; i++) {
 246                         err = regexec(&preg, ptr2, 1, &pmatch, 0);
 247                         if (err == REG_NOMATCH) {
 248                                 if (i == 0) {
 249                                         DEBUG2("rlm_attr_rewrite: No match found for attribute %s with value '%s'",
 250                                                         data->attribute, attr_vp->strvalue);
 251                                         regfree(&preg);
 252                                         goto to_do_again;
 253                                 } else
 254                                         break;
 255                         }
 256                         if (err != 0) {
 257                                 regfree(&preg);
 258                                 radlog(L_ERR, "rlm_attr_rewrite: match failure for attribute %s with value '%s'",
 259                                                 data->attribute, attr_vp->strvalue);
 260                                 return ret;
 261                         }
 262                         if (pmatch.rm_so == -1)
 263                                 break;
 264                         len = pmatch.rm_so;
 265                         if (data->append) {
 266                                 len = len + (pmatch.rm_eo - pmatch.rm_so);
 267                         }
 268                         counter += len;
 269                         if (counter >= MAX_STRING_LEN) {
 270                                 regfree(&preg);
 271                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 272                                                 data->attribute, attr_vp->strvalue);
 273                                 return ret;
 274                         }
 275
 276                         strncpy(ptr, ptr2,len);
 277                         ptr += len;
 278                         ptr2 += pmatch.rm_eo;
 279
 280                         if (!done_xlat){
 281                                 if (data->replace_len != 0 &&
 282                                 radius_xlat(replace_STR, sizeof(replace_STR), data->replace, request, NULL) == 0) {
 283                                         DEBUG2("rlm_attr_rewrite: xlat on replace string failed.");
 284                                         return ret;
 285                                 }
 286                                 replace_len = (data->replace_len != 0) ? strlen(replace_STR) : 0;
 287                                 done_xlat = 1;
 288                         }
 289
 290                         counter += replace_len;
 291                         if (counter >= MAX_STRING_LEN) {
 292                                 regfree(&preg);
 293                                 DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 294                                                 data->attribute, attr_vp->strvalue);
 295                                 return ret;
 296                         }
 297                         if (replace_len){
 298                                 strncpy(ptr, replace_STR, replace_len);
 299                                 ptr += replace_len;
 300                         }
 301                 }
 302                 regfree(&preg);
 303                 len = strlen(ptr2) + 1;         /* We add the ending NULL */
 304                 counter += len;
 305                 if (counter >= MAX_STRING_LEN){
 306                         DEBUG2("rlm_attr_rewrite: Replacement out of limits for attribute %s with value '%s'",
 307                                         data->attribute, attr_vp->strvalue);
 308                         return ret;
 309                 }
 310                 strncpy(ptr, ptr2, len);
 311
 312                 DEBUG2("rlm_attr_rewrite: Changed value for attribute %s from '%s' to '%s'",
 313                                 data->attribute, attr_vp->strvalue, new_str);
 314                 attr_vp->length = strlen(new_str);
 315                 strncpy(attr_vp->strvalue, new_str, (attr_vp->length + 1));
 316
 317 to_do_again:
 318                 ret = RLM_MODULE_OK;
 319
 320                 if (tmp != NULL){
 321                         tmp = attr_vp->next;
 322                         if (tmp != NULL)
 323                                 goto do_again;
 324                 }
 325         }
 326         else{
 327                 attr_vp = pairmake(data->attribute,replace_STR,0);
 328                 switch(data->searchin){
 329                         case RLM_REGEX_INPACKET:
 330                                 pairadd(&request->packet->vps,attr_vp);
 331                                 break;
 332                         case RLM_REGEX_INCONFIG:
 333                                 pairadd(&request->config_items,attr_vp);
 334                                 break;
 335                         case RLM_REGEX_INREPLY:
 336                                 pairadd(&request->reply->vps,attr_vp);
 337                                 break;
 338                         default:
 339                                 radlog(L_ERR, "rlm_attr_rewrite: Illegal value for searchin. Changing to packet.");
 340                                 data->searchin = RLM_REGEX_INPACKET;
 341                                 pairadd(&request->packet->vps,attr_vp);
 342                                 break;
 343                 }
 344                 DEBUG2("rlm_attr_rewrite: Added attribute %s with value '%s'",data->attribute,attr_vp->strvalue);
 345                 ret = RLM_MODULE_OK;
 346         }
 347
 348
 349         return ret;
 350 }
 351
 352
 353 static int attr_rewrite_accounting(void *instance, REQUEST *request)
 354 {
 355         return do_attr_rewrite(instance, request);
 356 }
 357
 358 static int attr_rewrite_authorize(void *instance, REQUEST *request)
 359 {
 360         return do_attr_rewrite(instance, request);
 361 }
 362 static int attr_rewrite_authenticate(void *instance, REQUEST *request)
 363 {
 364         return do_attr_rewrite(instance, request);
 365 }
 366 static int attr_rewrite_preacct(void *instance, REQUEST *request)
 367 {
 368         return do_attr_rewrite(instance, request);
 369 }
 370 static int attr_rewrite_ismul(void *instance, REQUEST *request)
 371 {
 372         return do_attr_rewrite(instance, request);
 373 }
 374
 375 static int attr_rewrite_preproxy(void *instance, REQUEST *request)
 376 {
 377         return do_attr_rewrite(instance, request);
 378 }
 379
 380 static int attr_rewrite_postproxy(void *instance, REQUEST *request)
 381 {
 382         return do_attr_rewrite(instance, request);
 383 }
 384
 385 static int attr_rewrite_postauth(void *instance, REQUEST *request)
 386 {
 387         return do_attr_rewrite(instance, request);
 388 }
 389
 390 static int attr_rewrite_detach(void *instance)
 391 {
 392         rlm_attr_rewrite_t *data = (rlm_attr_rewrite_t *) instance;
 393
 394         if (data->attribute)
 395                 free(data->attribute);
 396         if (data->search)
 397                 free(data->search);
 398         if (data->replace)
 399                 free(data->replace);
 400         if (data->name)
 401                 free(data->name);
 402
 403         free(instance);
 404         return 0;
 405 }
 406
 407 /*
 408  *      The module name should be the only globally exported symbol.
 409  *      That is, everything else should be 'static'.
 410  *
 411  *      If the module needs to temporarily modify it's instantiation
 412  *      data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 413  *      The server will then take care of ensuring that the module
 414  *      is single-threaded.
 415  */
 416 module_t rlm_attr_rewrite = {
 417         "attr_rewrite",
 418         RLM_TYPE_THREAD_UNSAFE,         /* type */
 419         NULL,                           /* initialization */
 420         attr_rewrite_instantiate,               /* instantiation */
 421         {
 422                 attr_rewrite_authenticate,      /* authentication */
 423                 attr_rewrite_authorize,         /* authorization */
 424                 attr_rewrite_preacct,           /* preaccounting */
 425                 attr_rewrite_accounting,        /* accounting */
 426                 attr_rewrite_ismul,             /* checksimul */
 427                 attr_rewrite_preproxy,          /* pre-proxy */
 428                 attr_rewrite_postproxy,         /* post-proxy */
 429                 attr_rewrite_postauth           /* post-auth */
 430         },
 431         attr_rewrite_detach,                    /* detach */
 432         NULL,                           /* destroy */
 433 };