1 | /***************************************
2 | $Revision: 1.9 $
3 |
4 | Radix tree (rx). rx_node.c - functions to operate on nodes of the tree
5 | (creation/deletion).
6 |
7 | Status: NOT REVUED, TESTED, INCOMPLETE
8 |
9 | Design and implementation by: Marek Bukowy
10 |
11 | ******************/ /******************
12 | Copyright (c) 1999 RIPE NCC
13 |
14 | All Rights Reserved
15 |
16 | Permission to use, copy, modify, and distribute this software and its
17 | documentation for any purpose and without fee is hereby granted,
18 | provided that the above copyright notice appear in all copies and that
19 | both that copyright notice and this permission notice appear in
20 | supporting documentation, and that the name of the author not be
21 | used in advertising or publicity pertaining to distribution of the
22 | software without specific, written prior permission.
23 |
24 | THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
25 | ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL
26 | AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
27 | DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
28 | AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
29 | OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
30 | ***************************************/
31 |
32 | #include <erroutines.h>
33 | #include <rxroutines.h>
34 | #include <memwrap.h>
35 | #include <stubs.h>
36 | #include <glib.h>
37 |
38 | #include <comparisons.h>
39 |
40 | /***************************************************************************/
41 | /*++++++++++++++++
42 | rx_creat_node = create a new data node
43 | (empty{glue} nodes get created automatically).
44 |
45 | Takes a pointer to the (already allocated) data leaf to be included
46 | in the list of data nodes (presumably empty as the node is only now being
47 | created).
48 |
49 | Requires a stack of nodes created in CREAT mode (with glue nodes,
50 | until deep enough and the last node being non-glue).
51 |
52 | MT notes: requires the tree to be locked.
53 |
54 | Returns: RX_OK or error code.
55 |
56 | +++++++++++++++++*/
57 | static
58 | er_ret_t
59 | rx_creat_node (
60 | ip_prefix_t *newpref, /*+ prefix of the node to be added +*/
61 | rx_tree_t *tree, /*+ tree the new node goes to +*/
62 | rx_dataleaf_t *dataleaf, /*+ dataleaf to attach at this node+*/
63 | rx_nodcpy_t stack[], /*+ stack==array of node_copies +*/
64 | int stackdepth /*+ length of the stack +*/
65 | )
66 | {
67 | rx_node_t *newnode, *curnode, *memnode, *gluenode;
68 | int chk_bit, dif_bit, link, curpos;
69 | char buf[1024];
70 | er_ret_t err;
71 |
72 | // assume no such node yet. Will die if there is one.
73 |
74 | // calloc, because parent/child keys and child ptrs are not always set.
75 |
76 | if( (err=wr_calloc( (void **) & newnode, 1, sizeof(rx_node_t))) != UT_OK) {
77 | return err;
78 | }
79 |
80 | // increment the number of nodes in the tree
81 | tree -> num_nodes ++;
82 |
83 | newnode -> prefix = *newpref;
84 |
85 | // attach the leaf to a (presumably empty?! hence NULL) list...
86 | newnode->leaves_ptr = g_list_prepend(NULL, dataleaf);
87 | newnode->glue = 0;
88 |
89 | // OK, so take a look at the tree
90 |
91 | if ( tree -> num_nodes == 1 ) {
92 | // The tree was empty. Create a new top node.
93 |
94 | tree -> top_ptr = newnode;
95 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT, "Created as the top node");
96 | return RX_OK;
97 | }
98 |
99 | // OK, there is at least one node in the tree. Take a look at the stack.
100 |
101 | // we've got a real node there (not a glue), but we may be too deep.
102 | // (it's not a glue, because glues have always two children.
103 | // we had to go that deep because from a glue alone one doesn't know
104 | // what it glues)
105 | // GO UP.
106 | // take the first differing bit from comparing
107 | // the new and the found nodes' prefixes.
108 | // (not deeper than the shorter of the two)
109 |
110 | curpos = stackdepth-1;
111 | curnode = & stack[curpos].cpy;
112 |
113 | chk_bit = smaller(curnode->prefix.bits, newpref->bits );
114 |
115 | for(dif_bit = 0; dif_bit < chk_bit; dif_bit++) {
116 | // break the loop when the first different bit is found
117 |
118 | if( IP_addr_bit_get( & curnode->prefix.ip, dif_bit)
119 | != IP_addr_bit_get( & newpref->ip, dif_bit) ) {
120 | break;
121 | }
122 | }
123 |
124 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_DET,
125 | "cur = %d, new = %d, chk_bit = %d, dif_bit = %d",
126 | curnode->prefix.bits, newpref->bits, chk_bit, dif_bit );
127 |
128 | if(dif_bit == IP_sizebits(newpref->ip.space)) die; // it mustn't happen!!!
129 |
130 | // go up to that level (watch the head of the tree!)
131 |
132 | while( curpos > 0 && stack[curpos-1].cpy.prefix.bits >= dif_bit) {
133 | curpos--;
134 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_DET,
135 | "up to level %d", curpos );
136 | }
137 |
138 | /*
139 | if the bit lenghts of the node, new prefix and the diffbit are equal
140 | {
141 | YOU'VE GOT THE NODE where the new one will be attached.
142 | Either it has data (and will be moved accordingly),
143 | or is a glue (and will be turned into a regular node).
144 | }
145 | */
146 |
147 | curnode = & stack[curpos].cpy;
148 |
149 | // RAM: set a pointer to the real node in memory
150 | memnode = stack[curpos].srcptr;
151 |
152 | if( dif_bit == newpref->bits
153 | && dif_bit == curnode->prefix.bits ) {
154 |
155 | // such node already exists, nothing to change in the tree!!!
156 | // this should be checked before calling this function, so..
157 |
158 | die;
159 | }
160 | /*
161 | else ** the branch ends here; we must create a new node... **
162 | {
163 | OK, how is the new node's prefix length w.r.t the dif_bit ?
164 | longer -> make it a child of the node found
165 | shorter -> make it the parent of the node found and take its place
166 | equal -> make a glue node the parent of both
167 | }
168 |
169 | WHEN ATTACHING THE NODE, VALUES FROM THE STACK ARE USED,
170 | TO PREVENT EXCESSIVE LOOKUPS AGAIN.
171 |
172 | */
173 | else {
174 |
175 | // **** attach it.
176 | if( ER_is_traced(FAC_RX, ASP_RX_NODCRE_DET) ) {
177 | rx_nod_print(curnode, buf, 1024);
178 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_DET, "Looking at node %s", buf);
179 | }
180 |
181 | if( curnode -> prefix.bits == dif_bit ) {
182 |
183 | // attach here as a child of the node found
184 | link = IP_addr_bit_get( &newpref->ip, dif_bit );
185 |
186 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT, "attaching as child %d", link);
187 |
188 | if( memnode -> child_ptr[link] != NULL ) {
189 | die;
190 | }
191 |
192 | memnode -> child_ptr[link] = newnode;
193 | newnode -> parent_ptr = memnode;
194 | }
195 | else if ( newpref->bits == dif_bit ) {
196 | // make it the parent of the node found and take its place,
197 | // moving it down.
198 |
199 | // set the link from the NEW node to the OLD one (different than before)
200 |
201 | link = IP_addr_bit_get( &curnode->prefix.ip, dif_bit );
202 |
203 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT, "shifting down as child %d", link);
204 |
205 | // PARENT<->NEW LINKS
206 | // see if the node was the top_node
207 | if (curnode -> parent_ptr == NULL) {
208 | // update tree struct
209 | tree -> top_ptr = newnode;
210 | } else {
211 | // no - fix the child link at the parent.
212 | // at the link where it was attached
213 | int link = (curnode->parent_ptr->child_ptr[1] == memnode);
214 | memnode -> parent_ptr -> child_ptr[link] = newnode;
215 | }
216 | memnode -> parent_ptr = newnode;
217 |
218 | // NEW<->CHILD LINKS
219 | newnode -> parent_ptr = curnode->parent_ptr;
220 | newnode -> child_ptr[link] = memnode;
221 | }
222 | else {
223 | // create a glue and shift the curnode below the glue,
224 | // then attach the new node at the glue
225 |
226 | // calloc, because parent/child keys are not set.
227 |
228 | if( (err=wr_calloc( (void **)& gluenode, 1, sizeof(rx_node_t))) != UT_OK) {
229 | return err; // die;
230 | }
231 | tree -> num_nodes ++;
232 |
233 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT, "created glue node at %p", gluenode);
234 |
235 | gluenode -> prefix.bits = dif_bit;
236 |
237 | // fill in the address. The glue node should get the prefix
238 | // shorter by one than the shorter of the two prefixes that are glued
239 | // (difbit)
240 | //
241 |
242 | gluenode -> prefix.ip = newpref->ip;
243 | gluenode -> prefix.bits = dif_bit;
244 |
245 | // the ip in this prefix is probably incorrect. Fix it.
246 | IP_pref_bit_fix( & gluenode -> prefix );
247 |
248 | gluenode -> leaves_ptr = NULL;
249 | gluenode -> glue = 1;
250 |
251 | // 1. Fix the link to and from the parent to the gluenode.
252 |
253 | gluenode -> parent_ptr = curnode->parent_ptr;
254 | if (gluenode->parent_ptr == NULL) {
255 | tree -> top_ptr = gluenode;
256 | }
257 | else {
258 | // fix the child link in the parent.
259 | // if it was at 1, then let fix the link 1, 0 otherwise
260 |
261 | link = (curnode->parent_ptr->child_ptr[1] == memnode);
262 |
263 | memnode->parent_ptr->child_ptr[link] = gluenode;
264 | }
265 |
266 | // 2. Fix the links between gluenode and the OLD node
267 |
268 | link = IP_addr_bit_get( &newpref->ip, dif_bit );
269 |
270 | gluenode -> child_ptr[ ! link ] = memnode;
271 | memnode->parent_ptr = gluenode;
272 |
273 | // 3. Fix the links between gluenode and the NEW node
274 |
275 | gluenode -> child_ptr[ link ] = newnode;
276 | newnode -> parent_ptr = gluenode;
277 | }
278 | return RX_OK;
279 | }
280 | die;
281 | return -1; //this is just to calm down the compiler
282 | }
283 |
284 |
285 | /***************************************************************************/
286 | /*+ hook for g_list_foreach to free a list element +*/
287 |
288 | void
289 | rx_free_list_element(void *cpy, void *trash)
290 | {
291 | wr_free(cpy);
292 | }
293 |
294 | /***************************************************************************/
295 | /*+++++++++++++++++++
296 |
297 | General function to operate on dataleaves attached to a single node
298 | (create / modify / delete).
299 |
300 | searches tree, finds and creates (modifies/deletes) a node,
301 | copies modified nodes to disk using rx_sql_node_set (not yet implemented).
302 | Updates memory rollback info.
303 |
304 | Currently only creation is implemented.
305 |
306 | Add a dataleaf at node defined by prefix. Create a new node if it doesn't
307 | exist yet.
308 |
309 | MT notes: requires the tree to be locked.
310 |
311 | Returns: RX_OK or error code.
312 |
313 | Errors from:
314 | rx_bin_search,
315 | memory alloc routines.
316 |
317 | - no such node (if not in create mode)
318 |
319 | - too many nodes found (strange).
320 |
321 | +++++++++++++++++*/
322 |
323 | er_ret_t
324 | RX_bin_node (
325 | rx_oper_mt mode, /*+ MODE={cre|mod|del} +*/
326 | ip_prefix_t *newpref, /*+ prefix of the node +*/
327 | rx_tree_t *tree, /*+ pointer to the tree structure +*/
328 | rx_dataleaf_t *dataleaf /*+ dataleaf to attach at the node +*/
329 | )
330 |
331 | {
332 | GList *nodlist = NULL;
333 | int nodesfound, stackdepth;
334 | int glue;
335 | rx_nodcpy_t *curcpy;
336 | rx_node_t *curnode;
337 | rx_nodcpy_t *stack;
338 | er_ret_t err;
339 | char bbf[IP_PREFSTR_MAX];
340 |
341 |
342 | if( ER_is_traced( FAC_RX, ASP_RX_NODCRE_BOT)) {
343 | IP_pref_b2a( newpref , bbf, IP_PREFSTR_MAX);
344 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT,
345 | "rx_bin_node: new %s in spc %d /fam %d /reg %d",
346 | bbf, tree->space, tree->family, tree->reg_id);
347 | }
348 |
349 | // first check: are we using the correct tree ???
350 | if( tree->space != newpref->ip.space ) {
351 | /* trying to insert a prefix of space %d into a tree of space %d\n",
352 | tree->space,
353 | newpref->ip.space);
354 | */
355 | die;
356 | }
357 |
358 | assert( newpref->bits <= IP_sizebits(tree->space) );
359 |
360 | // fix the prefix, to make sure all insignificant bits are 0
361 | IP_pref_bit_fix( newpref );
362 |
363 | if( (err=wr_malloc( (void **) &stack,
364 | sizeof(rx_nodcpy_t) * IP_sizebits(tree->space))) != UT_OK) {
365 | return err; //die;
366 | }
367 |
368 | if( (err=rx_build_stack(stack, &stackdepth,
369 | tree, newpref, RX_STK_CREAT) != RX_OK )) {
370 | return err; //die
371 | }
372 |
373 | // rx_stk_print(stack, stackdepth);
374 |
375 | // perform a search on the stack. The result is a list, and it must
376 | // be properly deleted after use!!
377 |
378 | if( rx_nod_search(RX_SRCH_CREAT, 0, 0,
379 | tree, newpref, stack, stackdepth,
380 | &nodlist, RX_ANS_ALL) != RX_OK ) {
381 | return err; // die;
382 | }
383 |
384 |
385 | // count number of nodes in the answer
386 | nodesfound = g_list_length (nodlist);
387 |
388 | switch( nodesfound ) {
389 | case 0:
390 | /* no such node (yet). See what we're up to.
391 | if( mode==cre ) create, else - program error, die */
392 |
393 | if( mode != RX_OPER_CRE) {
394 | die;
395 | }
396 |
397 | /* C R E A T I O N */
398 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT,
399 | "Creating a new node ");
400 | rx_creat_node( newpref, tree, dataleaf, stack, stackdepth );
401 | break;
402 | case 1: /* found */
403 | switch( mode ) {
404 | case RX_OPER_CRE:
405 | // attach the data at the node that was found;
406 |
407 | curcpy = g_list_nth_data(nodlist, 0);
408 |
409 | curnode = curcpy->srcptr;
410 | // was it glue ?
411 | glue = curnode->glue;
412 |
413 | curnode->leaves_ptr = g_list_prepend(curnode->leaves_ptr, dataleaf);
414 | // not it's not a glue anymore
415 | curnode->glue = 0;
416 |
417 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT, "Appended data to a %s node",
418 | glue ? "glue" : "data");
419 |
420 | break;
421 | case RX_OPER_MOD:
422 | // put new data in;
423 | break;
424 | case RX_OPER_DEL:
425 | break;
426 | // fine, check the number of children:
427 | // 0 - just delete,
428 | // 1 - copy the child's link to parent. then delete
429 | // 2 - turn into a glue
430 | }
431 | break;
432 | default:
433 | /* too many nodes found! from an exact/exact-less-1 search.
434 | this cannot happen. Call Ghostbusters now.
435 | */
436 | die;
437 | }
438 |
439 | g_list_foreach(nodlist, rx_free_list_element, NULL);
440 |
441 | wr_free(stack);
442 | return RX_OK;
443 | }
444 |
445 | /***************************************************************************/
446 | /*+++++++++++++++
447 | performs the actual update for inetnums (possibly composed of many prefixes).
448 | Decomposes the ranges into prefixes and then falls back to rx_bin_node
449 | to perform changes at the nodes.
450 |
451 | Requires/returns - practically the same as rx_bin_node.
452 | ++++++++++++++++*/
453 |
454 | er_ret_t
455 | RX_inum_node( rx_oper_mt mode, /*+ MODE={cre|mod|del} +*/
456 | ip_range_t *rang, /*+ range of IP addresses +*/
457 | rx_tree_t *tree, /*+ pointer to the tree structure +*/
458 | rx_dataleaf_t *leafptr /*+ dataleaf to attach at the node +*/
459 | )
460 | {
461 | int i, prefcount;
462 | GList *preflist = NULL;
463 | char buf[IP_RANGSTR_MAX];
464 |
465 | if( ER_is_traced( FAC_RX, ASP_RX_NODCRE_BOT)) {
466 | IP_rang_b2a(rang, buf, IP_RANGSTR_MAX );
467 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT,
468 | "rx_inum_node: adding %s", buf);
469 | }
470 |
471 | // decompose, put links to the data leaf into every prefix
472 | // that makes up this range.
473 | IP_rang_decomp(rang, &preflist);
474 |
475 | // see if there is more than 1 prefix, set the composed flag
476 | prefcount = g_list_length(preflist);
477 | leafptr->composed = (prefcount > 1) ;
478 |
479 | leafptr->iprange = *rang;
480 |
481 | for(i=0; i < prefcount; i++) {
482 | ip_prefix_t *mypref = g_list_nth_data(preflist, i);
483 |
484 | RX_bin_node(mode, mypref, tree, leafptr);
485 | }
486 |
487 | // free the storage from decomposition
488 | g_list_foreach(preflist, rx_free_list_element, NULL);
489 | g_list_free(preflist);
490 |
491 | return RX_OK;
492 | }
493 |
494 |
495 | /***************************************************************************/
496 | /*+++++++++++++++
497 | translates ranges/prefixes into binary prefixes.
498 | finds tree, locks it.
499 | initiates memory rollback structure (???)
500 |
501 | builds a dataleaf and puts into the node(s),
502 | calling rx_bin_node for every prefix.
503 |
504 | checks rollback condition and (possibly) rolls back ???
505 |
506 | MT-note: locks/unlocks the tree.
507 |
508 | Possible errors
509 | - all errors from:
510 | ip_asc_2_bin,
511 | rx_get_tree,
512 | rx_bin_node,
513 | wr_free
514 |
515 | +++++++++++++++++*/
516 | er_ret_t
517 | RX_asc_node ( rx_oper_mt mode, /*+ MODE={cre|mod|del} +*/
518 | char *rangstr, /*+ string prefix/range/IP +*/
519 | rx_regid_t reg_id, /*+ id of the registry +*/
520 | ip_space_t spc_id, /*+ type of space (ipv4/ipv6) +*/
521 | rx_fam_t fam_id, /*+ family of objects (route/inetnum) +*/
522 | void *data /*+ pointer to the payload +*/
523 | )
524 |
525 | {
526 |
527 | /*
528 | For creation of a new node:
529 |
530 | READ-LOCK THE FOREST
531 |
532 | get the root tree for this space (rx_get_tree)
533 | got it ? good. No ? error!!!
534 |
535 | Check if any of the prefixes spans more than one subtree...
536 | Check if they all exist already..
537 |
538 | if any is missing
539 | then
540 | WRITE-LOCK THE FOREST
541 | fi
542 |
543 | for all missing subtrees
544 | create missing trees
545 | rof
546 |
547 | UNLOCK THE FOREST
548 |
549 | **now start writing the data:**
550 |
551 | put *data* records in memory and sql table
552 |
553 | for all matchind [sub]trees (in order of the list)
554 | WRITE-LOCK the in-memory [sub]tree
555 | WRITE-LOCK the sql-table for it
556 |
557 | for(all prefixes in memory that match this tree)
558 | create a node in the tree pointing to the data
559 | rof
560 | UNLOCK the tree
561 | rof
562 |
563 |
564 | */
565 |
566 |
567 | ip_range_t myrang;
568 | ip_prefix_t mypref;
569 | rx_dataleaf_t *leafptr;
570 | rx_tree_t *mytree;
571 | int rang_ok;
572 |
573 | if( RX_get_tree ( &mytree, reg_id, spc_id, fam_id) != RX_OK ) {
574 | die;
575 | }
576 |
577 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT,
578 | "rx_asc_node: inserting object %s", rangstr);
579 |
580 | // set the data leaf values
581 | if( wr_calloc( (void **)& leafptr, sizeof(rx_dataleaf_t), 1)
582 | != UT_OK) {
583 | die;
584 | }
585 |
586 | leafptr->data_ptr = data;
587 |
588 | switch( fam_id )
589 | {
590 | case RX_FAM_IN:
591 | rang_ok = 1;
592 |
593 | if( IP_rang_e2b(&myrang, rangstr) == IP_OK ) {
594 | // that's nice. everything is set.
595 | } else {
596 | // see if's a valid IP, maybe it's an IPv4 classful range
597 | if( IP_addr_e2b( &myrang.begin, rangstr ) == IP_OK ) {
598 | if( IP_rang_classful( &myrang , &myrang.begin ) != IP_OK ) {
599 | rang_ok = 0;
600 | }
601 | }
602 | else {
603 | // sorry. we don't accept that.
604 | rang_ok = 0;
605 | }
606 | }
607 |
608 | if( rang_ok == 1 ) {
609 | return RX_inum_node( mode, &myrang, mytree, leafptr );
610 | }
611 | // else: fall through to the end of the function. (unrecognized arg)
612 |
613 | break;
614 |
615 | case RX_FAM_RT:
616 | if( IP_pref_e2b(&mypref, rangstr) == IP_OK ) {
617 | return RX_bin_node(RX_OPER_CRE, &mypref, mytree, leafptr);
618 | }
619 | }
620 |
621 | ER_dbg_va(FAC_RX, ASP_RX_NODCRE_BOT,
622 | "can't understand the key, discarding the OBJECT.");
623 | wr_free(data);
624 | wr_free(leafptr);
625 |
626 | return RX_BADKEY;
627 | }
628 |