src/main/valuepair.c

   1 /*
   2  * valuepair.c  Valuepair functions that are radiusd-specific
   3  *              and as such do not belong in the library.
   4  *
   5  * Version:     $Id$
   6  *
   7  *   This program is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License as published by
   9  *   the Free Software Foundation; either version 2 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This program is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with this program; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  * Copyright 2000  The FreeRADIUS server project
  22  * Copyright 2000  Alan DeKok <aland@ox.org>
  23  */
  24
  25 static const char rcsid[] = "$Id$";
  26
  27 #include "autoconf.h"
  28 #include "libradius.h"
  29
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33
  34 #ifdef HAVE_NETINET_IN_H
  35 #       include <netinet/in.h>
  36 #endif
  37
  38 #ifdef HAVE_REGEX_H
  39 #       include <regex.h>
  40
  41 /*
  42  *  For POSIX Regular expressions.
  43  *  (0) Means no extended regular expressions.
  44  *  REG_EXTENDED means use extended regular expressions.
  45  */
  46 #ifndef REG_EXTENDED
  47 #define REG_EXTENDED (0)
  48 #endif
  49
  50 #ifndef REG_NOSUB
  51 #define REG_NOSUB (0)
  52 #endif
  53 #endif
  54
  55 #include "radiusd.h"
  56
  57 struct cmp {
  58         int attribute;
  59         int otherattr;
  60         void *instance; /* module instance */
  61         RAD_COMPARE_FUNC compare;
  62         struct cmp *next;
  63 };
  64 static struct cmp *cmp;
  65
  66
  67 /*
  68  *      Compare 2 attributes. May call the attribute compare function.
  69  */
  70 static int paircompare(REQUEST *req, VALUE_PAIR *request, VALUE_PAIR *check,
  71                        VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
  72 {
  73         int ret = -2;
  74         struct cmp *c;
  75
  76         /*
  77          *      Sanity check.
  78          */
  79 #if 0
  80         if (request->attribute != check->attribute)
  81                 return -2;
  82 #endif
  83
  84         /*
  85          *      Check for =* and !* and return appropriately
  86          */
  87         if( check->operator == T_OP_CMP_TRUE )
  88                  return 0;  /* always return 0/EQUAL */
  89         if( check->operator == T_OP_CMP_FALSE )
  90                  return 1;  /* always return 1/NOT EQUAL */
  91
  92         /*
  93          *      See if there is a special compare function.
  94          */
  95         for (c = cmp; c; c = c->next)
  96                 if (c->attribute == check->attribute)
  97                         return (c->compare)(c->instance, req, request, check,
  98                                 check_pairs, reply_pairs);
  99
 100         switch(check->type) {
 101 #ifdef ASCEND_BINARY
 102                 /*
 103                  *      Ascend binary attributes can be treated
 104                  *      as opaque objects, I guess...
 105                  */
 106                 case PW_TYPE_ABINARY:
 107 #endif
 108                 case PW_TYPE_OCTETS:
 109                         if (request->length != check->length) {
 110                                 ret = 1; /* NOT equal */
 111                                 break;
 112                         }
 113                         ret = memcmp(request->strvalue, check->strvalue,
 114                                         request->length);
 115                         break;
 116                 case PW_TYPE_STRING:
 117                         ret = strcmp((char *)request->strvalue,
 118                                         (char *)check->strvalue);
 119                         break;
 120                 case PW_TYPE_INTEGER:
 121                 case PW_TYPE_DATE:
 122                         ret = request->lvalue - check->lvalue;
 123                         break;
 124                 case PW_TYPE_IPADDR:
 125                         ret = ntohl(request->lvalue) - ntohl(check->lvalue);
 126                         break;
 127                 default:
 128                         break;
 129         }
 130
 131         return ret;
 132 }
 133
 134
 135 /*
 136  *      See what attribute we want to compare with.
 137  */
 138 static int otherattr(int attr)
 139 {
 140         struct cmp      *c;
 141
 142         for (c = cmp; c; c = c->next) {
 143                 if (c->attribute == attr)
 144                         return c->otherattr;
 145         }
 146
 147         return attr;
 148 }
 149
 150 /*
 151  *      Register a function as compare function.
 152  *      compare_attr is the attribute in the request we want to
 153  *      compare with. Normally this is the same as "attr".
 154  *      You can set this to:
 155  *
 156  *      -1   the same as "attr"
 157  *      0    always call compare function, not tied to request attribute
 158  *      >0   Attribute to compare with.
 159  *
 160  *      For example, PW_GROUP in a check item needs to be compared
 161  *      with PW_USER_NAME in the incoming request.
 162  */
 163 int paircompare_register(int attr, int compare_attr, RAD_COMPARE_FUNC fun, void *instance)
 164 {
 165         struct cmp      *c;
 166
 167         paircompare_unregister(attr, fun);
 168
 169         c = rad_malloc(sizeof(struct cmp));
 170
 171         if (compare_attr < 0)
 172                 compare_attr = attr;
 173         c->compare = fun;
 174         c->attribute = attr;
 175         c->otherattr = compare_attr;
 176         c->instance = instance;
 177         c->next = cmp;
 178         cmp = c;
 179
 180         return 0;
 181 }
 182
 183 /*
 184  *      Unregister a function.
 185  */
 186 void paircompare_unregister(int attr, RAD_COMPARE_FUNC fun)
 187 {
 188         struct cmp      *c, *last;
 189
 190         last = NULL;
 191         for (c = cmp; c; c = c->next) {
 192                 if (c->attribute == attr && c->compare == fun)
 193                         break;
 194                 last = c;
 195         }
 196
 197         if (c == NULL) return;
 198
 199         if (last != NULL)
 200                 last->next = c->next;
 201         else
 202                 cmp = c->next;
 203
 204         free(c);
 205 }
 206
 207 /*
 208  *      Compare two pair lists except for the password information.
 209  *      For every element in "check" at least one matching copy must
 210  *      be present in "reply".
 211  *
 212  *      Return 0 on match.
 213  */
 214 int paircmp(REQUEST *req, VALUE_PAIR *request, VALUE_PAIR *check, VALUE_PAIR **reply)
 215 {
 216         VALUE_PAIR *check_item;
 217         VALUE_PAIR *auth_item;
 218         int result = 0;
 219         int compare;
 220         int other;
 221 #ifdef HAVE_REGEX_H
 222         regex_t reg;
 223 #endif
 224
 225         for (check_item = check; check_item != NULL; check_item = check_item->next) {
 226                 /*
 227                  *      If the user is setting a configuration value,
 228                  *      then don't bother comparing it to any attributes
 229                  *      sent to us by the user.  It ALWAYS matches.
 230                  */
 231                 if ((check_item->operator == T_OP_SET) ||
 232                     (check_item->operator == T_OP_ADD)) {
 233                         continue;
 234                 }
 235
 236                 switch (check_item->attribute) {
 237                         /*
 238                          *      Attributes we skip during comparison.
 239                          *      These are "server" check items.
 240                          */
 241                         case PW_CRYPT_PASSWORD:
 242                         case PW_AUTH_TYPE:
 243                         case PW_AUTZ_TYPE:
 244                         case PW_ACCT_TYPE:
 245                         case PW_SESSION_TYPE:
 246                         case PW_STRIP_USER_NAME:
 247                                 continue;
 248                                 break;
 249
 250                         /*
 251                          *      IF the password attribute exists, THEN
 252                          *      we can do comparisons against it.  If not,
 253                          *      then the request did NOT contain a
 254                          *      User-Password attribute, so we CANNOT do
 255                          *      comparisons against it.
 256                          *
 257                          *      This hack makes CHAP-Password work..
 258                          */
 259                         case PW_PASSWORD:
 260                                 if (pairfind(request, PW_PASSWORD) == NULL) {
 261                                         continue;
 262                                 }
 263                                 break;
 264                 }
 265
 266                 /*
 267                  *      See if this item is present in the request.
 268                  */
 269                 other = otherattr(check_item->attribute);
 270
 271                 auth_item = request;
 272         try_again:
 273                 for (; auth_item != NULL; auth_item = auth_item->next) {
 274                         if (auth_item->attribute == other || other == 0)
 275                                 break;
 276                 }
 277
 278                 /*
 279                  *      Not found, it's not a match.
 280                  */
 281                 if (auth_item == NULL) {
 282                         /*
 283                          *      Didn't find it.  If we were *trying*
 284                          *      to not find it, then we succeeded.
 285                          */
 286                         if (check_item->operator == T_OP_CMP_FALSE)
 287                                 return 0;
 288                         else
 289                                 return -1;
 290                 }
 291
 292                 /*
 293                  *      Else we found it, but we were trying to not
 294                  *      find it, so we failed.
 295                  */
 296                 if (check_item->operator == T_OP_CMP_FALSE)
 297                         return -1;
 298
 299
 300                 /*
 301                  *      We've got to xlat the string before doing
 302                  *      the comparison.
 303                  */
 304                 if (check_item->flags.do_xlat) {
 305                         int rcode;
 306                         char buffer[sizeof(check_item->strvalue)];
 307
 308                         check_item->flags.do_xlat = 0;
 309                         rcode = radius_xlat(buffer, sizeof(buffer),
 310                                             check_item->strvalue,
 311                                             req, NULL);
 312
 313                         /*
 314                          *      Parse the string into a new value.
 315                          */
 316                         pairparsevalue(check_item, buffer);
 317                 }
 318
 319                 /*
 320                  *      OK it is present now compare them.
 321                  */
 322                 compare = paircompare(req, auth_item, check_item, check, reply);
 323
 324                 switch (check_item->operator) {
 325                         case T_OP_EQ:
 326                         default:
 327                                 radlog(L_ERR,  "Invalid operator for item %s: "
 328                                                 "reverting to '=='", check_item->name);
 329                                 /*FALLTHRU*/
 330                         case T_OP_CMP_TRUE:    /* compare always == 0 */
 331                         case T_OP_CMP_FALSE:   /* compare always == 1 */
 332                         case T_OP_CMP_EQ:
 333                                 if (compare != 0) result = -1;
 334                                 break;
 335
 336                         case T_OP_NE:
 337                                 if (compare == 0) result = -1;
 338                                 break;
 339
 340                         case T_OP_LT:
 341                                 if (compare >= 0) result = -1;
 342                                 break;
 343
 344                         case T_OP_GT:
 345                                 if (compare <= 0) result = -1;
 346                                 break;
 347
 348                         case T_OP_LE:
 349                                 if (compare > 0) result = -1;
 350                                 break;
 351
 352                         case T_OP_GE:
 353                                 if (compare < 0) result = -1;
 354                                 break;
 355
 356 #ifdef HAVE_REGEX_H
 357                         case T_OP_REG_EQ:
 358                         {
 359                                 int i;
 360                                 regmatch_t rxmatch[9];
 361
 362                                 /*
 363                                  *      Include substring matches.
 364                                  */
 365                                 regcomp(&reg, (char *)check_item->strvalue,
 366                                         REG_EXTENDED);
 367                                 compare = regexec(&reg,
 368                                                   (char *)auth_item->strvalue,
 369                                                   16, rxmatch, 0);
 370                                 regfree(&reg);
 371
 372                                 /*
 373                                  *      Add %{0}, %{1}, etc.
 374                                  */
 375                                 for (i = 0; i <= 8; i++) {
 376                                         char *p;
 377                                         char buffer[sizeof(check_item->strvalue)];
 378
 379                                         /*
 380                                          *      Didn't match: delete old
 381                                          *      match, if it existed.
 382                                          */
 383                                         if ((compare != 0) ||
 384                                             (rxmatch[i].rm_so == -1)) {
 385                                                 p = request_data_get(req, req,
 386                                                                      REQUEST_DATA_REGEX | i);
 387                                                 if (p) {
 388                                                         free(p);
 389                                                         continue;
 390                                                 }
 391
 392                                                 /*
 393                                                  *      No previous match
 394                                                  *      to delete, stop.
 395                                                  */
 396                                                 break;
 397                                         }
 398
 399                                         /*
 400                                          *      Copy substring into buffer.
 401                                          */
 402                                         memcpy(buffer,
 403                                                auth_item->strvalue + rxmatch[i].rm_so,
 404                                                rxmatch[i].rm_eo - rxmatch[i].rm_so);
 405                                         buffer[rxmatch[i].rm_eo - rxmatch[i].rm_so] = '\0';
 406
 407                                         /*
 408                                          *      Copy substring, and add it to
 409                                          *      the request.
 410                                          *
 411                                          *      Note that we don't check
 412                                          *      for out of memory, which is
 413                                          *      the only error we can get...
 414                                          */
 415                                         p = strdup(buffer);
 416                                         request_data_add(req,
 417                                                          req,
 418                                                          REQUEST_DATA_REGEX | i,
 419                                                          p, free);
 420                                 }
 421                         }
 422                                 if (compare != 0) result = -1;
 423                                 break;
 424
 425                         case T_OP_REG_NE:
 426                                 regcomp(&reg, (char *)check_item->strvalue, REG_EXTENDED|REG_NOSUB);
 427                                 compare = regexec(&reg, (char *)auth_item->strvalue,
 428                                                 0, NULL, 0);
 429                                 regfree(&reg);
 430                                 if (compare == 0) result = -1;
 431                                 break;
 432 #endif
 433
 434                 } /* switch over the operator of the check item */
 435
 436                 /*
 437                  *      This attribute didn't match, but maybe there's
 438                  *      another of the same attribute, which DOES match.
 439                  */
 440                 if (result != 0) {
 441                         auth_item = auth_item->next;
 442                         result = 0;
 443                         goto try_again;
 444                 }
 445
 446         } /* for every entry in the check item list */
 447
 448         return 0;               /* it matched */
 449 }
 450
 451 /*
 452  *      Compare two attributes simply.  Calls paircompare.
 453  */
 454
 455 int simplepaircmp(REQUEST *req, VALUE_PAIR *first, VALUE_PAIR *second)
 456 {
 457         return paircompare( req, first, second, NULL, NULL );
 458 }
 459
 460
 461 /*
 462  *      Compare a Connect-Info and a Connect-Rate
 463  */
 464 static int connectcmp(void *instance,
 465                       REQUEST *req UNUSED,
 466                       VALUE_PAIR *request,
 467                       VALUE_PAIR *check,
 468                       VALUE_PAIR *check_pairs,
 469                       VALUE_PAIR **reply_pairs)
 470 {
 471         int rate;
 472
 473         instance = instance;
 474         check_pairs = check_pairs; /* shut the compiler up */
 475         reply_pairs = reply_pairs;
 476
 477         rate = atoi((char *)request->strvalue);
 478         return rate - check->lvalue;
 479 }
 480
 481
 482 /*
 483  *      Compare a portno with a range.
 484  */
 485 static int portcmp(void *instance,
 486                    REQUEST *req UNUSED, VALUE_PAIR *request, VALUE_PAIR *check,
 487         VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 488 {
 489         char buf[MAX_STRING_LEN];
 490         char *s, *p;
 491         uint32_t lo, hi;
 492         uint32_t port = request->lvalue;
 493
 494         instance = instance;
 495         check_pairs = check_pairs; /* shut the compiler up */
 496         reply_pairs = reply_pairs;
 497
 498         if ((strchr((char *)check->strvalue, ',') == NULL) &&
 499                         (strchr((char *)check->strvalue, '-') == NULL)) {
 500                 return (request->lvalue - check->lvalue);
 501         }
 502
 503         /* Same size */
 504         strcpy(buf, (char *)check->strvalue);
 505         s = strtok(buf, ",");
 506
 507         while (s != NULL) {
 508                 if ((p = strchr(s, '-')) != NULL)
 509                         p++;
 510                 else
 511                         p = s;
 512                 lo = strtoul(s, NULL, 10);
 513                 hi = strtoul(p, NULL, 10);
 514                 if (lo <= port && port <= hi) {
 515                         return 0;
 516                 }
 517                 s = strtok(NULL, ",");
 518         }
 519
 520         return -1;
 521 }
 522
 523 /*
 524  *      Compare prefix/suffix.
 525  *
 526  *      If they compare:
 527  *      - if PW_STRIP_USER_NAME is present in check_pairs,
 528  *        strip the username of prefix/suffix.
 529  *      - if PW_STRIP_USER_NAME is not present in check_pairs,
 530  *        add a PW_STRIPPED_USER_NAME to the request.
 531  */
 532 static int presufcmp(void *instance,
 533                      REQUEST *req UNUSED,
 534                      VALUE_PAIR *request, VALUE_PAIR *check,
 535         VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 536 {
 537         VALUE_PAIR *vp;
 538         char *name = (char *)request->strvalue;
 539         char rest[MAX_STRING_LEN];
 540         int len, namelen;
 541         int ret = -1;
 542
 543         instance = instance;
 544         reply_pairs = reply_pairs; /* shut the compiler up */
 545
 546 #if 0 /* DEBUG */
 547         printf("Comparing %s and %s, check->attr is %d\n",
 548                 name, check->strvalue, check->attribute);
 549 #endif
 550
 551         len = strlen((char *)check->strvalue);
 552         switch (check->attribute) {
 553                 case PW_PREFIX:
 554                         ret = strncmp(name, (char *)check->strvalue, len);
 555                         if (ret == 0 && rest)
 556                                 strcpy(rest, name + len);
 557                         break;
 558                 case PW_SUFFIX:
 559                         namelen = strlen(name);
 560                         if (namelen < len)
 561                                 break;
 562                         ret = strcmp(name + namelen - len,
 563                                         (char *)check->strvalue);
 564                         if (ret == 0 && rest) {
 565                                 strNcpy(rest, name, namelen - len + 1);
 566                         }
 567                         break;
 568         }
 569         if (ret != 0)
 570                 return ret;
 571
 572         if (pairfind(check_pairs, PW_STRIP_USER_NAME)) {
 573                 /*
 574                  *      I don't think we want to update the User-Name
 575                  *      attribute in place... - atd
 576                  */
 577                 strcpy((char *)request->strvalue, rest);
 578                 request->length = strlen(rest);
 579         } else {
 580                 if ((vp = pairfind(check_pairs, PW_STRIPPED_USER_NAME)) != NULL){
 581                         strcpy((char *)vp->strvalue, rest);
 582                         vp->length = strlen(rest);
 583                 } else if ((vp = paircreate(PW_STRIPPED_USER_NAME,
 584                                 PW_TYPE_STRING)) != NULL) {
 585                         strcpy((char *)vp->strvalue, rest);
 586                         vp->length = strlen(rest);
 587                         pairadd(&request, vp);
 588                 } /* else no memory! Die, die!: FIXME!! */
 589         }
 590
 591         return ret;
 592 }
 593
 594
 595 /*
 596  *      Compare the current time to a range.
 597  */
 598 static int timecmp(void *instance,
 599                    REQUEST *req UNUSED,
 600                    VALUE_PAIR *request, VALUE_PAIR *check,
 601         VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 602 {
 603         instance = instance;
 604         request = request;      /* shut the compiler up */
 605         check_pairs = check_pairs;
 606         reply_pairs = reply_pairs;
 607
 608         if (timestr_match((char *)check->strvalue,
 609                           req ? req->timestamp : time(NULL)) >= 0) {
 610                 return 0;
 611         }
 612         return -1;
 613 }
 614
 615 /*
 616  *      Matches if there is NO SUCH ATTRIBUTE as the one named
 617  *      in check->strvalue.  If there IS such an attribute, it
 618  *      doesn't match.
 619  *
 620  *      This is ugly, and definitely non-optimal.  We should be
 621  *      doing the lookup only ONCE, and storing the result
 622  *      in check->lvalue...
 623  */
 624 static int attrcmp(void *instance,
 625                    REQUEST *req UNUSED,
 626                    VALUE_PAIR *request, VALUE_PAIR *check,
 627                    VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 628 {
 629         VALUE_PAIR *pair;
 630         DICT_ATTR  *dict;
 631         int attr;
 632
 633         instance = instance;
 634         check_pairs = check_pairs; /* shut the compiler up */
 635         reply_pairs = reply_pairs;
 636
 637         if (check->lvalue == 0) {
 638                 dict = dict_attrbyname((char *)check->strvalue);
 639                 if (dict == NULL) {
 640                         return -1;
 641                 }
 642                 attr = dict->attr;
 643         } else {
 644                 attr = check->lvalue;
 645         }
 646
 647         /*
 648          *      If there's no such attribute, then return MATCH,
 649          *      else FAILURE.
 650          */
 651         pair = pairfind(request, attr);
 652         if (pair == NULL) {
 653                 return 0;
 654         }
 655
 656         return -1;
 657 }
 658
 659 /*
 660  *      Compare the expiration date.
 661  */
 662 static int expirecmp(void *instance, REQUEST *req UNUSED,
 663                      VALUE_PAIR *request, VALUE_PAIR *check,
 664                      VALUE_PAIR *check_pairs, VALUE_PAIR **reply_pairs)
 665 {
 666         time_t now;
 667
 668         instance = instance;
 669         request = request;      /* shut the compiler up */
 670         check_pairs = check_pairs;
 671         reply_pairs = reply_pairs;
 672
 673         /*
 674          *  FIXME!  This should be request->timestamp!
 675          */
 676         now = time(NULL);
 677
 678         if (now <= (signed)check->lvalue) {
 679                 return 0;
 680         }
 681
 682         return +1;
 683 }
 684
 685 /*
 686  *      Compare the request packet type.
 687  */
 688 static int packetcmp(void *instance UNUSED, REQUEST *req,
 689                      VALUE_PAIR *request UNUSED,
 690                      VALUE_PAIR *check,
 691                      VALUE_PAIR *check_pairs UNUSED,
 692                      VALUE_PAIR **reply_pairs UNUSED)
 693 {
 694         if (req->packet->code == check->lvalue) {
 695                 return 0;
 696         }
 697
 698         return 1;
 699 }
 700
 701 /*
 702  *      Compare the response packet type.
 703  */
 704 static int responsecmp(void *instance UNUSED,
 705                        REQUEST *req,
 706                        VALUE_PAIR *request UNUSED,
 707                        VALUE_PAIR *check,
 708                        VALUE_PAIR *check_pairs UNUSED,
 709                        VALUE_PAIR **reply_pairs UNUSED)
 710 {
 711         if (req->reply->code == check->lvalue) {
 712                 return 0;
 713         }
 714
 715         return 1;
 716 }
 717
 718 /*
 719  *      Register server-builtin special attributes.
 720  */
 721 void pair_builtincompare_init(void)
 722 {
 723         paircompare_register(PW_NAS_PORT, -1, portcmp, NULL);
 724         paircompare_register(PW_PREFIX, PW_USER_NAME, presufcmp, NULL);
 725         paircompare_register(PW_SUFFIX, PW_USER_NAME, presufcmp, NULL);
 726         paircompare_register(PW_CONNECT_RATE, PW_CONNECT_INFO, connectcmp, NULL);
 727         paircompare_register(PW_CURRENT_TIME, 0, timecmp, NULL);
 728         paircompare_register(PW_NO_SUCH_ATTRIBUTE, 0, attrcmp, NULL);
 729         paircompare_register(PW_EXPIRATION, 0, expirecmp, NULL);
 730         paircompare_register(PW_PACKET_TYPE, 0, packetcmp, NULL);
 731         paircompare_register(PW_RESPONSE_PACKET_TYPE, 0, responsecmp, NULL);
 732 }
 733
 734 /*
 735  *      Move pairs, replacing/over-writing them, and doing xlat.
 736  */
 737 /*
 738  *      Move attributes from one list to the other
 739  *      if not already present.
 740  */
 741 void pairxlatmove(REQUEST *req, VALUE_PAIR **to, VALUE_PAIR **from)
 742 {
 743         VALUE_PAIR **tailto, *i, *j, *next;
 744         VALUE_PAIR *tailfrom = NULL;
 745         VALUE_PAIR *found;
 746
 747         /*
 748          *      Point "tailto" to the end of the "to" list.
 749          */
 750         tailto = to;
 751         for(i = *to; i; i = i->next) {
 752                 tailto = &i->next;
 753         }
 754
 755         /*
 756          *      Loop over the "from" list.
 757          */
 758         for(i = *from; i; i = next) {
 759                 next = i->next;
 760
 761                 /*
 762                  *      Don't move 'fallthrough' over.
 763                  */
 764                 if (i->attribute == PW_FALL_THROUGH) {
 765                         continue;
 766                 }
 767
 768                 /*
 769                  *      We've got to xlat the string before moving
 770                  *      it over.
 771                  */
 772                 if (i->flags.do_xlat) {
 773                         int rcode;
 774                         char buffer[sizeof(i->strvalue)];
 775
 776                         i->flags.do_xlat = 0;
 777                         rcode = radius_xlat(buffer, sizeof(buffer),
 778                                             i->strvalue,
 779                                             req, NULL);
 780
 781                         /*
 782                          *      Parse the string into a new value.
 783                          */
 784                         pairparsevalue(i, buffer);
 785                 }
 786
 787                 found = pairfind(*to, i->attribute);
 788                 switch (i->operator) {
 789
 790                         /*
 791                          *  If a similar attribute is found,
 792                          *  delete it.
 793                          */
 794                 case T_OP_SUB:          /* -= */
 795                         if (found) {
 796                                 if (!i->strvalue[0] ||
 797                                     (strcmp((char *)found->strvalue,
 798                                             (char *)i->strvalue) == 0)){
 799                                         pairdelete(to, found->attribute);
 800
 801                                         /*
 802                                          *      'tailto' may have been
 803                                          *      deleted...
 804                                          */
 805                                         tailto = to;
 806                                         for(j = *to; j; j = j->next) {
 807                                                 tailto = &j->next;
 808                                         }
 809                                 }
 810                         }
 811                         tailfrom = i;
 812                         continue;
 813                         break;
 814
 815                         /*
 816                          *  Add it, if it's not already there.
 817                          */
 818                 case T_OP_EQ:           /* = */
 819                         if (found) {
 820                                 tailfrom = i;
 821                                 continue; /* with the loop */
 822                         }
 823                         break;
 824
 825                         /*
 826                          *  If a similar attribute is found,
 827                          *  replace it with the new one.  Otherwise,
 828                          *  add the new one to the list.
 829                          */
 830                 case T_OP_SET:          /* := */
 831                         if (found) {
 832                                 VALUE_PAIR *vp;
 833
 834                                 vp = found->next;
 835                                 memcpy(found, i, sizeof(*found));
 836                                 found->next = vp;
 837                                 continue;
 838                         }
 839                         break;
 840
 841                         /*
 842                          *  FIXME: Add support for <=, >=, <, >
 843                          *
 844                          *  which will mean (for integers)
 845                          *  'make the attribute the smaller, etc'
 846                          */
 847
 848                         /*
 849                          *  Add the new element to the list, even
 850                          *  if similar ones already exist.
 851                          */
 852                 default:
 853                 case T_OP_ADD:          /* += */
 854                         break;
 855                 }
 856
 857                 if (tailfrom)
 858                         tailfrom->next = next;
 859                 else
 860                         *from = next;
 861
 862                 /*
 863                  *      If ALL of the 'to' attributes have been deleted,
 864                  *      then ensure that the 'tail' is updated to point
 865                  *      to the head.
 866                  */
 867                 if (!*to) {
 868                         tailto = to;
 869                 }
 870                 *tailto = i;
 871                 if (i) {
 872                         i->next = NULL;
 873                         tailto = &i->next;
 874                 }
 875         } /* loop over the 'from' list */
 876 }