2 * This program is is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License, version 2 if the
4 * License as published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * You should have received a copy of the GNU General Public License
12 * along with this program; if not, write to the Free Software
13 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
19 * @brief Cache values and merge them back into future requests.
21 * @copyright 2012-2013 The FreeRADIUS server project
25 #include <freeradius-devel/radiusd.h>
26 #include <freeradius-devel/modules.h>
27 #include <freeradius-devel/heap.h>
28 #include <freeradius-devel/rad_assert.h>
30 #define PW_CACHE_TTL 1140
31 #define PW_CACHE_STATUS_ONLY 1141
32 #define PW_CACHE_MERGE 1142
33 #define PW_CACHE_ENTRY_HITS 1143
36 * Define a structure for our module configuration.
38 * These variables do not need to be in a structure, but it's
39 * a lot cleaner to do so, and a pointer to the structure can
40 * be used as the instance handle.
42 typedef struct rlm_cache_t {
43 char const *xlat_name;
53 value_pair_map_t *maps; //!< Attribute map applied to users
56 pthread_mutex_t cache_mutex;
60 typedef struct rlm_cache_entry_t {
72 #define PTHREAD_MUTEX_LOCK pthread_mutex_lock
73 #define PTHREAD_MUTEX_UNLOCK pthread_mutex_unlock
75 #define PTHREAD_MUTEX_LOCK(_x)
76 #define PTHREAD_MUTEX_UNLOCK(_x)
79 #define MAX_ATTRMAP 128
82 * Compare two entries by key. There may only be one entry with
85 static int cache_entry_cmp(void const *one, void const *two)
87 rlm_cache_entry_t const *a = one;
88 rlm_cache_entry_t const *b = two;
90 return strcmp(a->key, b->key);
93 static void cache_entry_free(void *data)
95 rlm_cache_entry_t *c = data;
97 pairfree(&c->control);
105 * Compare two entries by expiry time. There may be multiple
106 * entries with the same expiry time.
108 static int cache_heap_cmp(void const *one, void const *two)
110 rlm_cache_entry_t const *a = one;
111 rlm_cache_entry_t const *b = two;
113 if (a->expires < b->expires) return -1;
114 if (a->expires > b->expires) return +1;
120 * Merge a cached entry into a REQUEST.
122 static void cache_merge(rlm_cache_t *inst, REQUEST *request,
123 rlm_cache_entry_t *c)
127 rad_assert(request != NULL);
128 rad_assert(c != NULL);
130 vp = pairfind(request->config_items, PW_CACHE_MERGE, 0, TAG_ANY);
131 if (vp && (vp->vp_integer == 0)) {
132 RDEBUG2("Told not to merge entry into request");
137 RDEBUG2("Merging cached control list:");
138 rdebug_pair_list(2, request, c->control);
140 pairadd(&request->config_items, paircopy(request, c->control));
143 if (c->packet && request->packet) {
144 RDEBUG2("Merging cached request list:");
145 rdebug_pair_list(2, request, c->packet);
147 pairadd(&request->packet->vps,
148 paircopy(request->packet, c->packet));
151 if (c->reply && request->reply) {
152 RDEBUG2("Merging cached reply list:");
153 rdebug_pair_list(2, request, c->reply);
155 pairadd(&request->reply->vps,
156 paircopy(request->reply, c->reply));
160 vp = paircreate(request->packet, PW_CACHE_ENTRY_HITS, 0);
161 rad_assert(vp != NULL);
163 vp->vp_integer = c->hits;
165 pairadd(&request->packet->vps, vp);
171 * Find a cached entry.
173 static rlm_cache_entry_t *cache_find(rlm_cache_t *inst, REQUEST *request,
177 rlm_cache_entry_t *c, my_c;
181 * Look at the expiry heap.
183 c = fr_heap_peek(inst->heap);
185 rad_assert(rbtree_num_elements(inst->cache) == 0);
190 * If it's time to expire an old entry, do so now.
192 if (c->expires < request->timestamp) {
193 fr_heap_extract(inst->heap, c);
194 rbtree_deletebydata(inst->cache, c);
198 * Is there an entry for this key?
201 c = rbtree_finddata(inst->cache, &my_c);
205 * Yes, but it expired, OR the "forget all" epoch has
206 * passed. Delete it, and pretend it doesn't exist.
208 if ((c->expires < request->timestamp) ||
209 (c->created < inst->epoch)) {
211 RDEBUG("Entry has expired, removing");
213 fr_heap_extract(inst->heap, c);
214 rbtree_deletebydata(inst->cache, c);
219 RDEBUG("Found entry for \"%s\"", key);
222 * Update the expiry time based on the TTL.
223 * A TTL of 0 means "delete from the cache".
225 vp = pairfind(request->config_items, PW_CACHE_TTL, 0, TAG_ANY);
227 if (vp->vp_integer == 0) goto delete;
229 ttl = vp->vp_integer;
230 c->expires = request->timestamp + ttl;
231 RDEBUG("Adding %d to the TTL", ttl);
240 * Add an entry to the cache.
242 static rlm_cache_entry_t *cache_add(rlm_cache_t *inst, REQUEST *request,
246 VALUE_PAIR *vp, *found, **to_req, **to_cache, **from;
252 value_pair_map_t const *map;
254 rlm_cache_entry_t *c;
257 if (rbtree_num_elements(inst->cache) >= inst->max_entries) {
258 RDEBUG("Cache is full: %d entries", inst->max_entries);
263 * TTL of 0 means "don't cache this entry"
265 vp = pairfind(request->config_items, PW_CACHE_TTL, 0, TAG_ANY);
266 if (vp && (vp->vp_integer == 0)) return NULL;
268 c = talloc_zero(inst, rlm_cache_entry_t);
269 c->key = talloc_typed_strdup(c, key);
270 c->created = c->expires = request->timestamp;
273 * Use per-entry TTL, or globally defined one.
276 ttl = vp->vp_integer;
282 RDEBUG("Creating entry for \"%s\"", key);
285 * Check to see if we need to merge the entry into the request
287 vp = pairfind(request->config_items, PW_CACHE_MERGE, 0, TAG_ANY);
288 if (vp && (vp->vp_integer == 0)) {
290 RDEBUG2("Told not to merge new entry into request");
293 for (map = inst->maps; map != NULL; map = map->next) {
294 rad_assert(map->dst && map->src);
297 * Specifying inner/outer request doesn't work here
298 * but there's no easy fix...
300 switch (map->dst->vpt_list) {
301 case PAIR_LIST_REQUEST:
302 to_cache = &c->packet;
305 case PAIR_LIST_REPLY:
306 to_cache = &c->reply;
309 case PAIR_LIST_CONTROL:
310 to_cache = &c->control;
319 * Resolve the destination in the current request.
320 * We need to add the to_cache there too if any of these
323 * - Map specifies an xlat'd string.
324 * - Map specifies a literal string.
325 * - Map src and dst lists differ.
326 * - Map src and dst attributes differ
329 if (merge && (!map->src->vpt_da ||
330 (map->src->vpt_list != map->dst->vpt_list) ||
331 (map->src->vpt_da != map->dst->vpt_da))) {
334 * It's ok if the list isn't valid here...
335 * It might be valid later when we merge
338 if (radius_request(&context, map->dst->vpt_request) == 0) {
339 to_req = radius_list(context, map->dst->vpt_list);
344 * We infer that src was an attribute ref from the fact
347 RDEBUG4(":: dst is \"%s\" src is \"%s\"",
348 fr_int2str(vpt_types, map->dst->type, "<INVALID>"),
349 fr_int2str(vpt_types, map->src->type, "<INVALID>"));
351 switch (map->src->type) {
357 da = map->src->vpt_da;
359 if (radius_request(&context, map->src->vpt_request) == 0) {
360 from = radius_list(context, map->src->vpt_list);
364 * Can't add the attribute if the list isn't
369 fr_cursor_init(&cursor, from);
370 found = fr_cursor_next_by_num(&cursor, da->attr, da->vendor, TAG_ANY);
372 RWDEBUG("\"%s\" not found, skipping",
377 RDEBUG("\t%s %s %s", map->dst->name,
378 fr_int2str(fr_tokens, map->op, "<INVALID>"),
385 vp = map->dst->type == VPT_TYPE_LIST ?
386 paircopyvp(c, found) :
387 paircopyvpdata(c, map->dst->vpt_da, found);
391 pairadd(to_cache, vp);
394 vp = paircopyvp(request, vp);
395 radius_pairmove(request, to_req, vp, false);
401 vp = map->dst->type == VPT_TYPE_LIST ?
402 paircopyvp(c, found) :
403 paircopyvpdata(c, map->dst->vpt_da, found);
407 pairadd(to_cache, vp);
410 vp = paircopyvp(request, vp);
411 radius_pairmove(request, to_req, vp, false);
414 } while ((found = fr_cursor_next_by_num(&cursor, da->attr, da->vendor, TAG_ANY)));
428 rad_assert(map->src->type == VPT_TYPE_LIST);
432 if (radius_request(&context, map->src->vpt_request) == 0) {
433 from = radius_list(context, map->src->vpt_list);
438 fr_cursor_init(&out, &found);
439 for (i = fr_cursor_init(&in, from);
441 i = fr_cursor_next(&in)) {
443 * Prevent cache control attributes being added to the cache.
445 switch (i->da->attr) {
447 case PW_CACHE_STATUS_ONLY:
449 case PW_CACHE_ENTRY_HITS:
450 RDEBUG("\tskipping %s", i->da->name);
456 vp = paircopyvp(c, i);
461 RDEBUG("\t%s %s %s:%s", map->dst->name,
462 fr_int2str(fr_tokens, map->op, "<INVALID>"),
463 fr_int2str(pair_lists, map->src->vpt_list, "<INVALID>"), vp->da->name);
465 fr_cursor_insert(&out, vp);
468 pairadd(to_cache, found);
470 vp = paircopy(request, found);
471 radius_pairmove(request, to_req, vp, false);
477 * It was most likely a double quoted string that now
478 * needs to be expanded.
481 if (radius_xlat(buffer, sizeof(buffer), request, map->src->name, NULL, NULL) <= 0) {
485 RDEBUG("\t%s %s \"%s\"", map->dst->name,
486 fr_int2str(fr_tokens, map->op, "<INVALID>"),
489 vp = pairalloc(map->dst, map->dst->vpt_da);
493 if (!pairparsevalue(vp, buffer)) {
498 pairadd(to_cache, vp);
501 vp = paircopyvp(request, vp);
502 radius_pairmove(request, to_req, vp, false);
509 case VPT_TYPE_LITERAL:
510 RDEBUG("\t%s %s '%s'", map->dst->name,
511 fr_int2str(fr_tokens, map->op, "<INVALID>"),
514 vp = pairalloc(map->dst, map->dst->vpt_da);
518 if (!pairparsevalue(vp, map->src->name)) {
523 pairadd(to_cache, vp);
526 vp = paircopyvp(request, vp);
527 radius_pairmove(request, to_req, vp, false);
538 if (!rbtree_insert(inst->cache, c)) {
539 REDEBUG("FAILED adding entry for key %s", key);
544 if (!fr_heap_insert(inst->heap, c)) {
545 REDEBUG("FAILED adding entry for key %s", key);
546 rbtree_deletebydata(inst->cache, c);
550 RDEBUG("Inserted entry, TTL %d seconds", ttl);
556 * Verify that the cache section makes sense.
558 static int cache_verify(rlm_cache_t *inst, value_pair_map_t **head)
560 value_pair_map_t *map;
562 if (radius_attrmap(cf_section_sub_find(inst->cs, "update"),
563 head, PAIR_LIST_REQUEST,
564 PAIR_LIST_REQUEST, MAX_ATTRMAP) < 0) {
569 cf_log_err_cs(inst->cs,
570 "Cache config must contain an update section, and "
571 "that section must not be empty");
576 for (map = *head; map != NULL; map = map->next) {
577 if ((map->dst->type != VPT_TYPE_ATTR) &&
578 (map->dst->type != VPT_TYPE_LIST)) {
579 cf_log_err(map->ci, "Left operand must be an attribute "
586 * Can't copy an xlat expansion or literal into a list,
587 * we don't know what type of attribute we'd need
590 * The only exception is where were using a unary
593 if ((map->dst->type == VPT_TYPE_LIST) &&
594 (map->op != T_OP_CMP_FALSE) &&
595 ((map->src->type == VPT_TYPE_XLAT) || (map->src->type == VPT_TYPE_LITERAL))) {
596 cf_log_err(map->ci, "Can't copy value into list (we don't know which attribute to create)");
601 switch (map->src->type) {
603 cf_log_err(map->ci, "Exec values are not allowed");
608 * Only =, :=, += and -= operators are supported for
611 case VPT_TYPE_LITERAL:
613 * @fixme: This should be moved into a common function
614 * with the check in do_compile_modupdate.
616 if (map->dst->type == VPT_TYPE_ATTR) {
620 MEM(vp = pairalloc(map->dst, map->dst->vpt_da));
623 ret = pairparsevalue(vp, map->src->name);
626 cf_log_err(map->ci, "%s", fr_strerror());
642 cf_log_err(map->ci, "Operator \"%s\" not "
643 "allowed for %s values",
644 fr_int2str(fr_tokens, map->op,
646 fr_int2str(vpt_types, map->src->type,
658 * Allow single attribute values to be retrieved from the cache.
660 static ssize_t cache_xlat(void *instance, REQUEST *request,
661 char const *fmt, char *out, size_t freespace)
663 rlm_cache_entry_t *c;
664 rlm_cache_t *inst = instance;
665 VALUE_PAIR *vp, *vps;
667 DICT_ATTR const *target;
672 list = radius_list_name(&p, PAIR_LIST_REQUEST);
674 target = dict_attrbyname(p);
676 REDEBUG("Unknown attribute \"%s\"", p);
680 PTHREAD_MUTEX_LOCK(&inst->cache_mutex);
681 c = cache_find(inst, request, fmt);
684 RDEBUG("No cache entry for key \"%s\"", fmt);
690 case PAIR_LIST_REQUEST:
694 case PAIR_LIST_REPLY:
698 case PAIR_LIST_CONTROL:
702 case PAIR_LIST_UNKNOWN:
703 PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
704 REDEBUG("Unknown list qualifier in \"%s\"", fmt);
708 PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
709 REDEBUG("Unsupported list \"%s\"",
710 fr_int2str(pair_lists, list, "¿Unknown?"));
714 vp = pairfind(vps, target->attr, target->vendor, TAG_ANY);
716 RDEBUG("No instance of this attribute has been cached");
721 len = vp_prints_value(out, freespace, vp, 0);
722 if (is_truncated(len, freespace)) {
723 PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
724 REDEBUG("Insufficient buffer space to write cached value");
728 PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
734 * A mapping of configuration file names to internal variables.
736 * Note that the string is dynamically allocated, so it MUST
737 * be freed. When the configuration file parse re-reads the string,
738 * it free's the old one, and strdup's the new one, placing the pointer
739 * to the strdup'd string into 'config.string'. This gets around
742 static const CONF_PARSER module_config[] = {
743 { "key", PW_TYPE_STRING_PTR | PW_TYPE_REQUIRED,
744 offsetof(rlm_cache_t, key), NULL, NULL},
745 { "ttl", PW_TYPE_INTEGER,
746 offsetof(rlm_cache_t, ttl), NULL, "500" },
747 { "max_entries", PW_TYPE_INTEGER,
748 offsetof(rlm_cache_t, max_entries), NULL, "16384" },
749 { "epoch", PW_TYPE_INTEGER,
750 offsetof(rlm_cache_t, epoch), NULL, "0" },
751 { "add_stats", PW_TYPE_BOOLEAN,
752 offsetof(rlm_cache_t, stats), NULL, "no" },
754 { NULL, -1, 0, NULL, NULL } /* end the list */
759 * Only free memory we allocated. The strings allocated via
760 * cf_section_parse() do not need to be freed.
762 static int mod_detach(void *instance)
764 rlm_cache_t *inst = instance;
766 talloc_free(inst->maps);
768 fr_heap_delete(inst->heap);
769 rbtree_free(inst->cache);
771 #ifdef HAVE_PTHREAD_H
772 pthread_mutex_destroy(&inst->cache_mutex);
779 * Instantiate the module.
781 static int mod_instantiate(CONF_SECTION *conf, void *instance)
783 rlm_cache_t *inst = instance;
787 inst->xlat_name = cf_section_name2(conf);
788 if (!inst->xlat_name) {
789 inst->xlat_name = cf_section_name1(conf);
793 * Register the cache xlat function
795 xlat_register(inst->xlat_name, cache_xlat, NULL, inst);
797 rad_assert(inst->key && *inst->key);
799 if (inst->ttl == 0) {
800 cf_log_err_cs(conf, "Must set 'ttl' to non-zero");
804 if (inst->epoch != 0) {
805 cf_log_err_cs(conf, "Must not set 'epoch' in the configuration files");
809 #ifdef HAVE_PTHREAD_H
810 if (pthread_mutex_init(&inst->cache_mutex, NULL) < 0) {
811 EDEBUG("Failed initializing mutex: %s",
820 inst->cache = rbtree_create(cache_entry_cmp, cache_entry_free, 0);
822 EDEBUG("Failed to create cache");
827 * The heap of entries to expire.
829 inst->heap = fr_heap_create(cache_heap_cmp,
830 offsetof(rlm_cache_entry_t, offset));
832 EDEBUG("Failed to create heap for the cache");
837 * Make sure the users don't screw up too badly.
839 if (cache_verify(inst, &inst->maps) < 0) {
847 * Do caching checks. Since we can update ANY VP list, we do
848 * exactly the same thing for all sections (autz / auth / etc.)
850 * If you want to cache something different in different sections,
851 * configure another cache module.
853 static rlm_rcode_t cache_it(void *instance, REQUEST *request)
855 rlm_cache_entry_t *c;
856 rlm_cache_t *inst = instance;
861 if (radius_xlat(buffer, sizeof(buffer), request, inst->key, NULL, NULL) < 0) {
862 return RLM_MODULE_FAIL;
865 PTHREAD_MUTEX_LOCK(&inst->cache_mutex);
866 c = cache_find(inst, request, buffer);
869 * If yes, only return whether we found a valid cache entry
871 vp = pairfind(request->config_items, PW_CACHE_STATUS_ONLY, 0, TAG_ANY);
872 if (vp && vp->vp_integer) {
873 rcode = c ? RLM_MODULE_OK:
879 cache_merge(inst, request, c);
881 rcode = RLM_MODULE_OK;
885 c = cache_add(inst, request, buffer);
887 rcode = RLM_MODULE_NOOP;
891 rcode = RLM_MODULE_UPDATED;
894 PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
900 * The module name should be the only globally exported symbol.
901 * That is, everything else should be 'static'.
903 * If the module needs to temporarily modify it's instantiation
904 * data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
905 * The server will then take care of ensuring that the module
906 * is single-threaded.
908 module_t rlm_cache = {
914 mod_instantiate, /* instantiation */
915 mod_detach, /* detach */
917 NULL, /* authentication */
918 cache_it, /* authorization */
919 cache_it, /* preaccounting */
920 cache_it, /* accounting */
921 NULL, /* checksimul */
922 cache_it, /* pre-proxy */
923 cache_it, /* post-proxy */
924 cache_it, /* post-auth */