src/modules/rlm_policy/evaluate.c

   1 /*
   2  * evaluate.c           Evaluate a policy language
   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  * Copyright 2004  Alan DeKok <aland@ox.org>
  21  * Copyright 2006  The FreeRADIUS server project
  22  */
  23
  24 #include <freeradius-devel/ident.h>
  25 RCSID("$Id$")
  26
  27 #include "rlm_policy.h"
  28
  29 #ifdef HAVE_REGEX_H
  30 #include <regex.h>
  31 #endif
  32
  33 #define debug_evaluate if (0) printf
  34
  35 /*
  36  *      Print stuff we've parsed
  37  */
  38 static void policy_print(const policy_item_t *item, int indent)
  39 {
  40         if (!item) {
  41                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
  42                 fprintf(fr_log_fp, "[NULL]\n");
  43                 return;
  44         }
  45
  46         while (item) {
  47                 switch (item->type) {
  48                 case POLICY_TYPE_BAD:
  49                         if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
  50                         fprintf(fr_log_fp, "[BAD STATEMENT]");
  51                         break;
  52
  53                 case POLICY_TYPE_PRINT:
  54                         if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
  55                         {
  56                                 const policy_print_t *this;
  57
  58                                 this = (const policy_print_t *) item;
  59
  60                                 if (this->rhs_type == POLICY_LEX_BARE_WORD) {
  61                                         fprintf(fr_log_fp, "print %s\n", this->rhs);
  62                                 } else {
  63                                         fprintf(fr_log_fp, "print \"%s\"\n", this->rhs);
  64                                 }
  65                         }
  66                         break;
  67
  68                 case POLICY_TYPE_ASSIGNMENT:
  69                         {
  70                                 const policy_assignment_t *assign;
  71
  72                                 assign = (const policy_assignment_t *) item;
  73                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
  74
  75                                 fprintf(fr_log_fp, "\t%s %s ", assign->lhs,
  76                                        fr_int2str(rlm_policy_tokens,
  77                                                     assign->assign, "?"));
  78                                 if (assign->rhs_type == POLICY_LEX_BARE_WORD) {
  79                                         fprintf(fr_log_fp, "%s\n", assign->rhs);
  80                                 } else {
  81                                         /*
  82                                          *      FIXME: escape "
  83                                          */
  84                                         fprintf(fr_log_fp, "\"%s\"\n", assign->rhs);
  85                                 }
  86                         }
  87                         break;
  88
  89                 case POLICY_TYPE_CONDITIONAL: /* no indentation here */
  90                         {
  91                                 const policy_condition_t *condition;
  92
  93                                 condition = (const policy_condition_t *) item;
  94
  95                                 fprintf(fr_log_fp, "(");
  96
  97                                 if (condition->sense) {
  98                                         fprintf(fr_log_fp, "!");
  99                                 }
 100
 101                                 /*
 102                                  *      Nested conditions.
 103                                  */
 104                                 if (condition->compare == POLICY_LEX_L_BRACKET) {
 105                                         policy_print(condition->child, indent);
 106                                         fprintf(fr_log_fp, ")");
 107                                         break;
 108                                 }
 109
 110                                 if (condition->compare == POLICY_LEX_L_NOT) {
 111                                         fprintf(fr_log_fp, "!");
 112                                         policy_print(condition->child, indent);
 113                                         fprintf(fr_log_fp, ")");
 114                                         break;
 115                                 }
 116
 117                                 if (condition->compare == POLICY_LEX_CMP_TRUE) {
 118                                         fprintf(fr_log_fp, "%s)", condition->lhs);
 119                                         break;
 120                                 }
 121
 122                                 if (condition->lhs_type == POLICY_LEX_FUNCTION) {
 123                                         fprintf(fr_log_fp, "%s()", condition->lhs);
 124                                 } else {
 125                                         /*
 126                                          *      FIXME: escape ",
 127                                          *      and move all of this logic
 128                                          *      to a function.
 129                                          */
 130                                         fprintf(fr_log_fp, "\"%s\"", condition->lhs);
 131                                 }
 132
 133                                 /*
 134                                  *      We always print this condition.
 135                                  */
 136                                 fprintf(fr_log_fp, " %s ", fr_int2str(rlm_policy_tokens,
 137                                                             condition->compare,
 138                                                             "?"));
 139                                 if (condition->rhs_type == POLICY_LEX_BARE_WORD) {
 140                                         fprintf(fr_log_fp, "%s", condition->rhs);
 141                                 } else {
 142                                         /*
 143                                          *      FIXME: escape ",
 144                                          *      and move all of this logic
 145                                          *      to a function.
 146                                          */
 147                                         fprintf(fr_log_fp, "\"%s\"", condition->rhs);
 148                                 }
 149                                 fprintf(fr_log_fp, ")");
 150
 151                                 if ((condition->child_condition != POLICY_LEX_BAD) &&
 152                                     (condition->child_condition != POLICY_LEX_BARE_WORD)) {
 153                                         fprintf(fr_log_fp, " %s ", fr_int2str(rlm_policy_tokens, condition->child_condition, "?"));
 154                                         policy_print(condition->child, indent);
 155                                 }
 156                         }
 157                         break;
 158
 159                 case POLICY_TYPE_IF:
 160                         {
 161                                 const policy_if_t *statement;
 162
 163                                 statement = (const policy_if_t *) item;
 164
 165                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 166                                 fprintf(fr_log_fp, "if ");
 167                                 policy_print(statement->condition, indent);
 168                                 fprintf(fr_log_fp, " {\n");
 169                                 policy_print(statement->if_true, indent + 1);
 170                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 171                                 if (statement->if_false) {
 172                                         fprintf(fr_log_fp, "} else ");
 173                                         if (statement->if_false->type == POLICY_TYPE_ASSIGNMENT) {
 174                                                 fprintf(fr_log_fp, " { ");
 175                                                 policy_print(statement->if_false, indent + 1);
 176                                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 177                                                 fprintf(fr_log_fp, " }");
 178                                         } else {
 179                                                 policy_print(statement->if_false, indent + 1);
 180                                         }
 181                                 } else {
 182                                         fprintf(fr_log_fp, "}\n");
 183                                 }
 184                         }
 185                         break;
 186
 187                 case POLICY_TYPE_ATTRIBUTE_LIST:
 188                         {
 189                                 const policy_attributes_t *this;
 190
 191                                 this = (const policy_attributes_t *) item;
 192
 193                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 194                                 fprintf(fr_log_fp, "%s %s {\n",
 195                                        fr_int2str(policy_reserved_words,
 196                                                     this->where, "?"),
 197                                        fr_int2str(rlm_policy_tokens,
 198                                                     this->how, "?"));
 199                                 policy_print(this->attributes, indent + 1);
 200                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 201                                 fprintf(fr_log_fp, "}\n");
 202                         }
 203                         break;
 204
 205                 case POLICY_TYPE_NAMED_POLICY:
 206                         {
 207                                 const policy_named_t *this;
 208
 209                                 this = (const policy_named_t *) item;
 210                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 211                                 fprintf(fr_log_fp, "policy %s {\n", this->name);
 212                                 policy_print(this->policy, indent + 1);
 213                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 214                                 fprintf(fr_log_fp, "}\n");
 215                         }
 216                         break;
 217
 218                 case POLICY_TYPE_CALL:
 219                         {
 220                                 const policy_call_t *this;
 221
 222                                 this = (const policy_call_t *) item;
 223                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 224                                 fprintf(fr_log_fp, "call %s\n", this->name);
 225                         }
 226                         break;
 227
 228                 case POLICY_TYPE_RETURN:
 229                         {
 230                                 const policy_return_t *this;
 231
 232                                 this = (const policy_return_t *) item;
 233                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 234                                 fprintf(fr_log_fp, "return %s\n",
 235                                        fr_int2str(policy_return_codes,
 236                                                     this->rcode, "???"));
 237                         }
 238                         break;
 239
 240                 case POLICY_TYPE_MODULE:
 241                         {
 242                                 const policy_module_t *this;
 243
 244                                 this = (const policy_module_t *) item;
 245                                 if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 246                                 fprintf(fr_log_fp, "module %s <stuff>\n",
 247                                        fr_int2str(policy_component_names,
 248                                                     this->component, "???"));
 249                         }
 250                         break;
 251
 252                 default:
 253                         if (indent) fprintf(fr_log_fp, "%*s", indent, " ");
 254                         fprintf(fr_log_fp, "[HUH?]\n");
 255                         break;
 256
 257                 }
 258
 259                 item = item->next;
 260         }
 261 }
 262
 263
 264 void rlm_policy_print(const policy_item_t *item)
 265 {
 266         if (!fr_log_fp) return;
 267
 268         fprintf(fr_log_fp, "# rlm_policy \n");
 269         policy_print(item, 0);
 270 }
 271
 272 /*
 273  *      Internal stack of things to do.  This lets us have function
 274  *      calls...
 275  *
 276  *      Yes, we should learn lex, yacc, etc.
 277  */
 278 #define POLICY_MAX_STACK 16
 279 typedef struct policy_state_t {
 280         rlm_policy_t    *inst;
 281         REQUEST         *request; /* so it's not passed on the C stack */
 282         int             rcode;  /* for functions, etc. */
 283         int             component; /* for calling other modules */
 284         int             depth;
 285         const policy_item_t *stack[POLICY_MAX_STACK];
 286 } policy_state_t;
 287
 288
 289 static int policy_evaluate_name(policy_state_t *state, const char *name);
 290
 291 /*
 292  *      Push an item onto the state.
 293  */
 294 static int policy_stack_push(policy_state_t *state, const policy_item_t *item)
 295 {
 296         rad_assert(state->depth >= 0);
 297
 298         /*
 299          *      Asked to push nothing.  Don't push it.
 300          */
 301         if (!item) return 1;
 302
 303         /*
 304          *      State is full.  Die.
 305          */
 306         if (state->depth >= POLICY_MAX_STACK) {
 307                 return 0;
 308         }
 309
 310         /*
 311          *      Walk back up the stack, looking for previous ocurrances
 312          *      of this name.  If found, we have infinite recursion,
 313          *      which we stop dead in the water!
 314          *
 315          *      This isn't strictly necessary right now, as we look up
 316          *      policies by name when they're first referenced.  This
 317          *      means that ALL references are backwards (to the start
 318          *      of the file), which means that there are no circular
 319          *      references.
 320          */
 321         if (item->type == POLICY_TYPE_NAMED_POLICY) {
 322                 int i;
 323
 324                 for (i = 0; i < state->depth; i++) {
 325                         /*
 326                          *      Check for circular references, by seeing
 327                          *      if the function is already on the stack.
 328                          *
 329                          *      Hmmm... do we want to do this for any type?
 330                          */
 331                         if (state->stack[i] == item) {
 332                                 debug_evaluate("Circular call to policy %s\n",
 333                                                ((const policy_named_t *) item)->name);
 334                                 return 0;
 335                         }
 336                 }
 337         }
 338
 339         debug_evaluate("push %d %p\n", state->depth, item);
 340
 341         state->stack[state->depth] = item;
 342         state->depth++;         /* points to unused entry */
 343
 344         return 1;
 345 }
 346
 347
 348 /*
 349  *      Pop an item from the state.
 350  */
 351 static int policy_stack_pop(policy_state_t *state, const policy_item_t **pitem)
 352 {
 353         rad_assert(pitem != NULL);
 354         rad_assert(state->depth >= 0);
 355
 356  redo:
 357         if (state->depth == 0) {
 358                 *pitem = NULL;
 359                 return 0;
 360         }
 361
 362         *pitem = state->stack[state->depth - 1];
 363
 364         /*
 365          *      Named policies are on the stack for catching recursion.
 366          */
 367         if ((*pitem)->type == POLICY_TYPE_NAMED_POLICY) {
 368                 state->depth--;
 369                 goto redo;
 370         }
 371
 372         /*
 373          *      Process the whole item list.
 374          */
 375         if ((*pitem)->next) {
 376                 state->stack[state->depth - 1] = (*pitem)->next;
 377                 debug_evaluate("pop/push %d %p\n", state->depth - 1, *pitem);
 378         } else {
 379                 state->depth--;         /* points to unused entry */
 380                 debug_evaluate("pop %d %p\n", state->depth, *pitem);
 381         }
 382
 383         return 1;
 384 }
 385
 386
 387 /*
 388  *      Evaluate a print statement
 389  */
 390 static int evaluate_print(policy_state_t *state, const policy_item_t *item)
 391 {
 392         const policy_print_t *this;
 393
 394         if (!fr_log_fp) return 1;
 395
 396         this = (const policy_print_t *) item;
 397
 398         if (this->rhs_type == POLICY_LEX_BARE_WORD) {
 399                 fprintf(fr_log_fp, "%s\n", this->rhs);
 400         } else {
 401                 char buffer[1024];
 402
 403                 radius_xlat(buffer, sizeof(buffer), this->rhs,
 404                             state->request, NULL);
 405                 fprintf(fr_log_fp, "%s", buffer);
 406                 if (!strchr(buffer, '\n')) fprintf(fr_log_fp, "\n");
 407         }
 408
 409         /*
 410          *      Doesn't change state->rcode
 411          */
 412
 413         return 1;
 414 }
 415
 416 /*
 417  *      Return a VALUE_PAIR, given an attribute name.
 418  *
 419  *      FIXME: Have it return the N'th one, too, like
 420  *      doc/variables.txt?
 421  *
 422  *      The amount of duplicated code is getting annoying...
 423  */
 424 static VALUE_PAIR *find_vp(REQUEST *request, const char *name)
 425 {
 426         const char *p;
 427         const DICT_ATTR *dattr;
 428         VALUE_PAIR *vps;
 429
 430         p = name;
 431         vps = request->packet->vps;;
 432
 433         /*
 434          *      FIXME: use names from reserved word list?
 435          */
 436         if (strncasecmp(name, "request:", 8) == 0) {
 437                 p += 8;
 438         } else if (strncasecmp(name, "reply:", 6) == 0) {
 439                 p += 6;
 440                 vps = request->reply->vps;
 441         } else if (strncasecmp(name, "proxy-request:", 14) == 0) {
 442                 p += 14;
 443                 if (request->proxy) {
 444                         vps = request->proxy->vps;
 445                 }
 446         } else if (strncasecmp(name, "proxy-reply:", 12) == 0) {
 447                 p += 12;
 448                 if (request->proxy_reply) {
 449                         vps = request->proxy_reply->vps;
 450                 }
 451         } else if (strncasecmp(name, "control:", 8) == 0) {
 452                 p += 8;
 453                 vps = request->config_items;
 454         } /* else it must be a bare attribute name */
 455
 456         if (!vps) {
 457                 return NULL;
 458         }
 459
 460         dattr = dict_attrbyname(p);
 461         if (!dattr) {
 462                 fprintf(stderr, "No such attribute %s\n", p);
 463                 return NULL;    /* no such attribute */
 464         }
 465
 466         return pairfind(vps, dattr->attr, dattr->vendor);
 467 }
 468
 469
 470 /*
 471  *      Evaluate an assignment
 472  *
 473  *      Not really used much...
 474  */
 475 static int evaluate_assignment(UNUSED policy_state_t *state, const policy_item_t *item)
 476 {
 477         const policy_assignment_t *this;
 478 #if 0
 479         const DICT_ATTR *dattr;
 480 #endif
 481
 482         this = (const policy_assignment_t *) item;
 483
 484         rad_assert(this->lhs != NULL);
 485         rad_assert(this->rhs != NULL);
 486
 487 #if 0
 488         dattr = dict_attrbyname(this->lhs);
 489         if (!dattr) {
 490                 fprintf(stderr, "HUH?\n");
 491                 return 0;
 492         }
 493 #endif
 494
 495         return 1;
 496 }
 497
 498
 499 /*
 500  *      Evaluate a condition
 501  */
 502 static int evaluate_condition(policy_state_t *state, const policy_item_t *item)
 503 {
 504         int rcode;
 505         const policy_condition_t *this;
 506         VALUE_PAIR *vp = NULL;
 507         const char *data = NULL;
 508         int compare;
 509 #ifdef HAVE_REGEX_H
 510         regex_t reg;
 511 #endif
 512         char buffer[256];
 513         char lhs_buffer[2048];
 514
 515         this = (const policy_condition_t *) item;
 516
 517  redo:
 518         /*
 519          *      FIXME: Don't always do this...
 520          */
 521         if (this->compare != POLICY_LEX_L_BRACKET) {
 522                 if (this->lhs_type == POLICY_LEX_FUNCTION) {
 523                         /*
 524                          *      We can't call evaluate_call here,
 525                          *      because that just pushes stuff onto
 526                          *      the stack, and we want to actually
 527                          *      evaluate all of it...
 528                          */
 529                         rcode = policy_evaluate_name(state, this->lhs);
 530                         data = fr_int2str(policy_return_codes, rcode, "???");
 531                         strlcpy(lhs_buffer, data, sizeof(lhs_buffer)); /* FIXME: yuck */
 532                 } else if (this->lhs_type == POLICY_LEX_DOUBLE_QUOTED_STRING) {
 533                         if (radius_xlat(lhs_buffer, sizeof(lhs_buffer), this->lhs,
 534                                         state->request, NULL) > 0) {
 535                                 data = lhs_buffer;
 536                         }
 537                 }
 538         }
 539
 540         switch (this->compare) {
 541         case POLICY_LEX_L_BRACKET: /* nested brackets are a special case */
 542                 rcode = evaluate_condition(state, this->child);
 543                 break;
 544
 545         case POLICY_LEX_L_NOT:
 546                 rcode = evaluate_condition(state, this->child);
 547                 rcode = (rcode == FALSE); /* reverse sense of test */
 548                 break;
 549
 550         case POLICY_LEX_CMP_FALSE: /* non-existence */
 551                 if (this->lhs_type == POLICY_LEX_BARE_WORD) {
 552                         vp = find_vp(state->request, this->lhs);
 553                         rcode = (vp == NULL);
 554                 } else {
 555                         rcode = (data == NULL);
 556                 }
 557                 break;
 558
 559         case POLICY_LEX_CMP_TRUE: /* existence */
 560                 if (this->lhs_type == POLICY_LEX_BARE_WORD) {
 561                         vp = find_vp(state->request, this->lhs);
 562                         rcode = (vp != NULL);
 563                 } else {
 564                         rcode = (data != NULL);
 565                 }
 566                 break;
 567
 568         default:                /* process other comparisons */
 569                 if ((this->compare != POLICY_LEX_CMP_EQUALS) &&
 570 #ifdef HAVE_REGEX_H
 571                     (this->compare != POLICY_LEX_RX_EQUALS) &&
 572                     (this->compare != POLICY_LEX_RX_NOT_EQUALS) &&
 573 #endif
 574                     (this->compare != POLICY_LEX_LT) &&
 575                     (this->compare != POLICY_LEX_GT) &&
 576                     (this->compare != POLICY_LEX_LE) &&
 577                     (this->compare != POLICY_LEX_GE) &&
 578                     (this->compare != POLICY_LEX_CMP_NOT_EQUALS)) {
 579                         fprintf(stderr, "%d: bad comparison\n",
 580                                 this->item.lineno);
 581                         return FALSE;
 582                 }
 583
 584                 if (this->lhs_type == POLICY_LEX_BARE_WORD) {
 585                         VALUE_PAIR *myvp;
 586
 587                         vp = find_vp(state->request, this->lhs);
 588
 589                         /*
 590                          *      A op B is FALSE if A doesn't
 591                          *      exist.
 592                          */
 593                         if (!vp) {
 594                                 rcode = FALSE;
 595                                 break;
 596                         }
 597
 598                         /*
 599                          *      FIXME: Move sanity checks to
 600                          *      post-parse code, so we don't do
 601                          *      it on every packet.
 602                          */
 603                         vp_prints_value(buffer, sizeof(buffer), vp, 0);
 604                         myvp = pairmake(vp->name, this->rhs, T_OP_EQ);
 605                         if (!myvp) return FALSE; /* memory failure */
 606                         data = buffer;
 607
 608                         /*
 609                          *      FIXME: What to do about comparisons
 610                          *      where vp doesn't exist?  Right now,
 611                          *      "simplepaircmp" returns -1, which is
 612                          *      probably a bad idea.  it should
 613                          *      instead take an operator, a pointer to
 614                          *      the comparison result, and return
 615                          *      "true/false" for "comparions
 616                          *      succeeded/failed", which are different
 617                          *      error codes than "comparison is less
 618                          *      than, equal to, or greater than zero".
 619                          */
 620                         compare = radius_callback_compare(state->request,
 621                                                           vp, myvp, NULL, NULL);
 622                         pairfree(&myvp);
 623
 624                 } else {
 625                         /*
 626                          *      FIXME: Do something for RHS type?
 627                          */
 628                         fr_printf_log("CMP %s %s\n", lhs_buffer, this->rhs);
 629                         compare = strcmp(lhs_buffer, this->rhs);
 630                 }
 631
 632                 debug_evaluate("CONDITION COMPARE %d\n", compare);
 633
 634                 switch (this->compare) {
 635                 case POLICY_LEX_CMP_EQUALS:
 636                         rcode = (compare == 0);
 637                         break;
 638
 639                 case POLICY_LEX_CMP_NOT_EQUALS:
 640                         rcode = (compare != 0);
 641                         break;
 642
 643                 case POLICY_LEX_LT:
 644                         rcode = (compare < 0);
 645                         break;
 646
 647                 case POLICY_LEX_GT:
 648                         rcode = (compare > 0);
 649                         break;
 650
 651                 case POLICY_LEX_LE:
 652                         rcode =(compare <= 0);
 653                         break;
 654
 655                 case POLICY_LEX_GE:
 656                         rcode = (compare >= 0);
 657                         break;
 658
 659 #ifdef HAVE_REGEX_H
 660                 case POLICY_LEX_RX_EQUALS:
 661                 { /* FIXME: copied from src/main/valuepair.c */
 662                         int i;
 663                         regmatch_t rxmatch[REQUEST_MAX_REGEX + 1];
 664
 665                         /*
 666                          *      Include substring matches.
 667                          */
 668                         if (regcomp(&reg, this->rhs,
 669                                     REG_EXTENDED) != 0) {
 670                                 /* FIXME: print error */
 671                                 return FALSE;
 672                         }
 673                         rad_assert(data != NULL);
 674                         rcode = regexec(&reg, data,
 675                                         REQUEST_MAX_REGEX + 1,
 676                                         rxmatch, 0);
 677                         rcode = (rcode == 0);
 678                         regfree(&reg);
 679
 680                         /*
 681                          *      Add %{0}, %{1}, etc.
 682                          */
 683                         for (i = 0; i <= REQUEST_MAX_REGEX; i++) {
 684                                 char *p;
 685                                 char rxbuffer[256];
 686
 687                                 /*
 688                                  *      Didn't match: delete old
 689                                  *      match, if it existed.
 690                                  */
 691                                 if (!rcode ||
 692                                     (rxmatch[i].rm_so == -1)) {
 693                                         p = request_data_get(state->request, state->request,
 694                                                              REQUEST_DATA_REGEX | i);
 695                                         if (p) {
 696                                                 free(p);
 697                                                 continue;
 698                                         }
 699
 700                                         /*
 701                                          *      No previous match
 702                                          *      to delete, stop.
 703                                          */
 704                                         break;
 705                                 }
 706
 707                                 /*
 708                                  *      Copy substring into buffer.
 709                                  */
 710                                 memcpy(rxbuffer,
 711                                        data + rxmatch[i].rm_so,
 712                                        rxmatch[i].rm_eo - rxmatch[i].rm_so);
 713                                 rxbuffer[rxmatch[i].rm_eo - rxmatch[i].rm_so] = '\0';
 714
 715                                 /*
 716                                  *      Copy substring, and add it to
 717                                  *      the request.
 718                                  *
 719                                  *      Note that we don't check
 720                                  *      for out of memory, which is
 721                                  *      the only error we can get...
 722                                  */
 723                                 p = strdup(rxbuffer);
 724                                 request_data_add(state->request,
 725                                                  state->request,
 726                                                  REQUEST_DATA_REGEX | i,
 727                                                  p, free);
 728                         }
 729
 730                 }
 731                 break;
 732
 733                 case POLICY_LEX_RX_NOT_EQUALS:
 734                         regcomp(&reg, this->rhs, REG_EXTENDED|REG_NOSUB);
 735                         rad_assert(data != NULL);
 736                         rcode = regexec(&reg, data,
 737                                         0, NULL, 0);
 738                         rcode = (rcode != 0);
 739                         regfree(&reg);
 740                                 break;
 741 #endif /* HAVE_REGEX_H */
 742                 default:
 743                         rcode = FALSE;
 744                         break;
 745                 } /* switch over comparison operators */
 746                 break;          /* default from first switch over compare */
 747         }
 748
 749         if (this->sense) rcode = (rcode == FALSE); /* reverse sense of test */
 750
 751         /*
 752          *      No trailing &&, ||
 753          */
 754         switch (this->child_condition) {
 755         default:
 756                 return rcode;
 757
 758         case POLICY_LEX_L_AND:
 759                 if (!rcode) return rcode; /* FALSE && x == FALSE */
 760                 break;
 761
 762         case POLICY_LEX_L_OR:
 763                 if (rcode) return rcode; /* TRUE && x == TRUE */
 764                 break;
 765         }
 766
 767         /*
 768          *      Tail recursion.
 769          */
 770         this = (const policy_condition_t *) this->child;
 771         goto redo;
 772
 773         return 1;               /* should never reach here */
 774 }
 775
 776
 777 /*
 778  *      Evaluate an 'if' statement
 779  */
 780 static int evaluate_if(policy_state_t *state, const policy_item_t *item)
 781 {
 782         int rcode;
 783         const policy_if_t *this;
 784
 785         this = (const policy_if_t *) item;
 786
 787         /*
 788          *      evaluate_condition calls itself recursively.
 789          *      We should probably allocate a new state, instead.
 790          */
 791         rcode = evaluate_condition(state, this->condition);
 792         debug_evaluate("IF condition returned %s\n",
 793                rcode ? "true" : "false");
 794         if (rcode) {
 795                 rcode = policy_stack_push(state, this->if_true);
 796                 if (!rcode) return rcode;
 797         } else if (this->if_false) {
 798                 rcode = policy_stack_push(state, this->if_false);
 799                 if (!rcode) return rcode;
 800         }
 801
 802         /*
 803          *      'if' can fail, if the block it's processing fails.
 804          */
 805         return 1;;
 806 }
 807
 808
 809 /*
 810  *      Make a VALUE_PAIR from a policy_assignment_t*
 811  *
 812  *      The assignment operator has to be '='.
 813  */
 814 static VALUE_PAIR *assign2vp(REQUEST *request,
 815                              const policy_assignment_t *assign)
 816 {
 817         VALUE_PAIR *vp;
 818         FR_TOKEN operator = T_OP_EQ;
 819         const char *value = assign->rhs;
 820         char buffer[2048];
 821
 822         if ((assign->rhs_type == POLICY_LEX_DOUBLE_QUOTED_STRING) &&
 823             (strchr(assign->rhs, '%') != NULL)) {
 824                 radius_xlat(buffer, sizeof(buffer), assign->rhs,
 825                             request, NULL);
 826                 value = buffer;
 827         }
 828
 829         /*
 830          *      This is crappy.. fix it.
 831          */
 832         switch (assign->assign) {
 833         case POLICY_LEX_ASSIGN:
 834                 operator = T_OP_EQ;
 835                 break;
 836
 837         case POLICY_LEX_SET_EQUALS:
 838                 operator = T_OP_SET;
 839                 break;
 840
 841         case POLICY_LEX_PLUS_EQUALS:
 842                 operator = T_OP_ADD;
 843                 break;
 844
 845         default:
 846                 fprintf(stderr, "Expected '=' for operator, not '%s' at line %d\n",
 847                         fr_int2str(rlm_policy_tokens,
 848                                      assign->assign, "?"),
 849                         assign->item.lineno);
 850                 return NULL;
 851         }
 852
 853         vp = pairmake(assign->lhs, value, operator);
 854         if (!vp) {
 855                 fprintf(stderr, "Failed creating pair: %s %s\n", value, fr_strerror());
 856         }
 857
 858         return vp;
 859 }
 860
 861
 862 /*
 863  *      Evaluate a 'packet .= {attrs}' statement
 864  */
 865 static int evaluate_attr_list(policy_state_t *state, const policy_item_t *item)
 866 {
 867         const policy_attributes_t *this;
 868         VALUE_PAIR **vps = NULL;
 869         VALUE_PAIR *vp, *head, **tail;
 870         const policy_item_t *attr;
 871         policy_lex_t this_how;
 872
 873         this = (const policy_attributes_t *) item;
 874
 875         switch (this->where) {
 876         case POLICY_RESERVED_CONTROL:
 877                 vps = &(state->request->config_items);
 878                 break;
 879
 880         case POLICY_RESERVED_REQUEST:
 881                 vps = &(state->request->packet->vps);
 882                 break;
 883
 884         case POLICY_RESERVED_REPLY:
 885                 vps = &(state->request->reply->vps);
 886                 break;
 887
 888         case POLICY_RESERVED_PROXY_REQUEST:
 889                 if (!state->request->proxy) return 0; /* FIXME: print error */
 890                 vps = &(state->request->proxy->vps);
 891                 break;
 892
 893         case POLICY_RESERVED_PROXY_REPLY:
 894                 if (!state->request->proxy_reply) return 0; /* FIXME: print error */
 895                 vps = &(state->request->proxy_reply->vps);
 896                 break;
 897
 898         default:
 899                 return 0;
 900         }
 901
 902         head = NULL;
 903         tail = &head;
 904
 905         for (attr = this->attributes; attr != NULL; attr = attr->next) {
 906                 if (attr->type != POLICY_TYPE_ASSIGNMENT) {
 907                         fprintf(stderr, "bad assignment in attribute list at line %d\n", attr->lineno);
 908                         pairfree(&head);
 909                         return 0;
 910                 }
 911
 912                 vp = assign2vp(state->request, (const policy_assignment_t *) attr);
 913                 if (!vp) {
 914                         fprintf(stderr, "Failed to allocate VP\n");
 915                         pairfree(&head);
 916                         return 0;
 917                 }
 918                 *tail = vp;
 919                 tail = &(vp->next);
 920         }
 921
 922         this_how = this->how;
 923  retry_how:
 924         switch (this_how) {
 925         case POLICY_LEX_SET_EQUALS: /* dangerous: removes all previous things! */
 926                 pairfree(vps);
 927                 *vps = head;
 928                 break;
 929
 930         case POLICY_LEX_AFTER_TAIL_ASSIGN:
 931                 pairmove(vps, &head);
 932                 pairfree(&head);
 933                 break;
 934
 935         case POLICY_LEX_ASSIGN: /* 'union' */
 936                 pairmove(vps, &head);
 937                 pairfree(&head);
 938                 break;
 939
 940         case POLICY_LEX_BEFORE_HEAD_ASSIGN:
 941                 pairmove(&head, vps);
 942                 pairfree(vps);
 943                 *vps = head;
 944                 break;
 945
 946         case POLICY_LEX_AFTER_TAIL_EQUALS:
 947         case POLICY_LEX_CONCAT_EQUALS:
 948                 pairadd(vps, head);
 949                 break;
 950
 951         case POLICY_LEX_BEFORE_HEAD_EQUALS:
 952                 pairadd(&head, *vps);
 953                 *vps = head;
 954                 break;
 955
 956         case POLICY_LEX_BEFORE_WHERE_EQUALS:
 957         case POLICY_LEX_AFTER_WHERE_EQUALS:
 958         case POLICY_LEX_BEFORE_WHERE_ASSIGN:
 959         case POLICY_LEX_AFTER_WHERE_ASSIGN:
 960                 /* find location*/
 961                 {
 962                         VALUE_PAIR *vpprev = NULL, *vpnext = NULL, *lvp;
 963
 964                         for(lvp = *vps; lvp; vpprev = lvp, lvp = lvp->next) {
 965                                 vpnext = lvp->next;
 966                                 lvp->next = NULL;
 967                                 if (evaluate_condition(state, this->where_loc))
 968                                         break;
 969                                 lvp->next = vpnext;
 970                         }
 971
 972                         if (lvp) {
 973                                 switch(this_how) {
 974                                 case POLICY_LEX_BEFORE_WHERE_EQUALS:
 975                                 case POLICY_LEX_BEFORE_WHERE_ASSIGN:
 976                                         if (vpprev) {
 977                                                 lvp->next = vpnext;
 978                                                 vpnext = lvp;
 979                                                 vpprev->next = NULL;
 980                                                 lvp = vpprev;
 981                                         }
 982                                 default: /* always reached */
 983                                         break;
 984                                 }
 985
 986                                 switch(this_how) {
 987                                 case POLICY_LEX_BEFORE_WHERE_EQUALS:
 988                                         if (vpprev)
 989                                                 pairadd(&lvp, head);
 990                                         else
 991                                                 *vps = lvp = head;
 992                                         break;
 993                                 case POLICY_LEX_AFTER_WHERE_EQUALS:
 994                                         pairadd(&lvp, head);
 995                                         break;
 996                                 case POLICY_LEX_BEFORE_WHERE_ASSIGN:
 997                                         if (vpprev) {
 998                                                 pairmove(&lvp, &head);
 999                                                 pairfree(&head);
1000                                         }
1001                                         else
1002                                                 *vps = lvp = head;
1003                                         break;
1004                                 case POLICY_LEX_AFTER_WHERE_ASSIGN:
1005                                         pairmove(&lvp, &head);
1006                                         pairfree(&head);
1007                                         break;
1008                                 default:/*never reached*/
1009                                         break;
1010                                 }
1011                                 for( ; lvp && lvp->next; lvp = lvp->next);
1012                                 if (lvp)
1013                                         lvp->next = vpnext;
1014                                 break;
1015                         }
1016
1017                         switch(this_how) {
1018                                 case POLICY_LEX_BEFORE_WHERE_EQUALS:
1019                                         this_how = POLICY_LEX_BEFORE_HEAD_EQUALS;
1020                                         break;
1021                                 case POLICY_LEX_AFTER_WHERE_EQUALS:
1022                                         this_how = POLICY_LEX_AFTER_TAIL_EQUALS;
1023                                         break;
1024                                 case POLICY_LEX_BEFORE_WHERE_ASSIGN:
1025                                         this_how = POLICY_LEX_BEFORE_HEAD_ASSIGN;
1026                                         break;
1027                                 case POLICY_LEX_AFTER_WHERE_ASSIGN:
1028                                         this_how = POLICY_LEX_AFTER_TAIL_ASSIGN;
1029                                         break;
1030                                 default: /*never reached*/
1031                                         break;
1032                         }
1033                         goto retry_how;
1034                 }
1035                 /* FALL-THROUGH */
1036
1037         default:
1038                 fprintf(stderr, "HUH?\n");
1039                 pairfree(&head);
1040                 return 0;
1041         }
1042
1043         state->rcode = RLM_MODULE_UPDATED; /* we did stuff */
1044
1045         return 1;
1046 }
1047
1048
1049 /*
1050  *      Evaluate a reference call to a module.
1051  */
1052 static int evaluate_call(policy_state_t *state, const policy_item_t *item)
1053 {
1054         int rcode;
1055         const policy_call_t *this;
1056         const policy_named_t *policy;
1057
1058         this = (const policy_call_t *) item;
1059
1060         policy = rlm_policy_find(state->inst->policies, this->name);
1061         if (!policy) return 0;  /* not found... */
1062
1063         DEBUG2("rlm_policy: Evaluating policy %s", this->name);
1064
1065         rad_assert(policy->policy->type != POLICY_TYPE_BAD);
1066         rad_assert(policy->policy->type < POLICY_TYPE_NUM_TYPES);
1067
1068         /*
1069          *      Push the name of the function onto the stack,
1070          *      so that we can catch recursive calls.
1071          *
1072          *      The "pop" function will skip over it when it sees it.
1073          */
1074         rcode = policy_stack_push(state, (const policy_item_t *) policy);
1075         if (!rcode) {
1076                 return rcode;
1077         }
1078
1079         /*
1080          *      Push it onto the stack.  Other code will take care of
1081          *      calling it.
1082          */
1083         rcode = policy_stack_push(state, policy->policy);
1084         if (!rcode) {
1085                 return rcode;
1086         }
1087
1088         return 1;
1089 }
1090
1091
1092 /*
1093  *      Evaluate a return statement
1094  */
1095 static int evaluate_return(policy_state_t *state, const policy_item_t *item)
1096 {
1097         const policy_return_t *this;
1098
1099         this = (const policy_return_t *) item;
1100         state->rcode = this->rcode;
1101
1102         return 1;               /* we succeeded */
1103 }
1104
1105
1106 /*
1107  *      Evaluate a module statement
1108  */
1109 static int evaluate_module(policy_state_t *state, const policy_item_t *item)
1110 {
1111         const policy_module_t *this;
1112
1113         this = (const policy_module_t *) item;
1114
1115         /*
1116          *      Just to be paranoid.  Maybe we want to loosen this
1117          *      restriction in the future?
1118          */
1119         if (this->component != state->component) {
1120                 DEBUG2("rlm_policy: Cannot mix & match components");
1121                 return 0;
1122         }
1123
1124         DEBUG2("rlm_policy: begin nested call");
1125         state->rcode = modcall(this->component, this->mc, state->request);
1126         DEBUG2("rlm_policy: end nested call");
1127
1128         return 1;               /* we succeeded */
1129 }
1130
1131
1132 /*
1133  *      State machine stuff.
1134  */
1135 typedef int (*policy_evaluate_type_t)(policy_state_t *, const policy_item_t *);
1136
1137
1138 /*
1139  *      MUST be kept in sync with policy_type_t
1140  */
1141 static policy_evaluate_type_t evaluate_functions[POLICY_TYPE_NUM_TYPES] = {
1142         NULL,                   /* POLICY_TYPE_BAD */
1143         evaluate_if,
1144         evaluate_condition,
1145         evaluate_assignment,
1146         evaluate_attr_list,
1147         evaluate_print,
1148         NULL,                   /* define a named policy.. */
1149         evaluate_call,
1150         evaluate_return,
1151         evaluate_module
1152 };
1153
1154
1155 /*
1156  *      Evaluate a policy, keyed by name.
1157  */
1158 static int policy_evaluate_name(policy_state_t *state, const char *name)
1159 {
1160         int rcode;
1161         const policy_item_t *this;
1162         policy_named_t mypolicy, *policy;
1163
1164         mypolicy.name = name;
1165         policy = rbtree_finddata(state->inst->policies, &mypolicy);
1166         if (!policy) return RLM_MODULE_FAIL;
1167
1168         DEBUG2("rlm_policy: Evaluating policy %s", name);
1169
1170         rad_assert(policy->item.type != POLICY_TYPE_BAD);
1171         rad_assert(policy->item.type < POLICY_TYPE_NUM_TYPES);
1172
1173         rcode = policy_stack_push(state, policy->policy);
1174         if (!rcode) {
1175                 return RLM_MODULE_FAIL;
1176         }
1177
1178         /*
1179          *      FIXME: Look for magic keywords like "return",
1180          *      where the packet gets accepted/rejected/whatever
1181          */
1182         while (policy_stack_pop(state, &this)) {
1183                 rad_assert(this != NULL);
1184                 rad_assert(this->type != POLICY_TYPE_BAD);
1185                 rad_assert(this->type < POLICY_TYPE_NUM_TYPES);
1186
1187                 debug_evaluate("Evaluating at line %d\n",
1188                                this->lineno);
1189                 rcode = (*evaluate_functions[this->type])(state,
1190                                                           this);
1191                 if (!rcode) {
1192                         return RLM_MODULE_FAIL;
1193                 }
1194         } /* loop until the stack is empty */
1195
1196         return state->rcode;
1197 }
1198
1199
1200 /*
1201  *      Evaluate, which is pretty close to print, but we look at what
1202  *      we're printing.
1203  */
1204 int rlm_policy_evaluate(rlm_policy_t *inst, REQUEST *request, const char *name)
1205 {
1206         int rcode;
1207         policy_state_t *state;
1208
1209         state = rad_malloc(sizeof(*state));
1210         memset(state, 0, sizeof(*state));
1211         state->request = request;
1212         state->inst = inst;
1213         state->rcode = RLM_MODULE_OK;
1214         state->component = fr_str2int(policy_component_names, name,
1215                                         RLM_COMPONENT_COUNT);
1216
1217         rcode = policy_evaluate_name(state, name);
1218
1219         free(state);
1220
1221         return rcode;           /* evaluated OK. */
1222 }