util_ldap_cache_mgr.c revision 2669b0829aa4efffd095ec93e41890d142fb74f0
/* Copyright 2001-2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* util_ldap_cache_mgr.c: LDAP cache manager things
*
* Original code from auth_ldap module for Apache v1.3:
* Copyright 1998, 1999 Enbridge Pipelines Inc.
* Copyright 1999-2001 Dave Carrigan
*/
#include <apr_ldap.h>
#include "util_ldap.h"
#include "util_ldap_cache.h"
#include <apr_strings.h>
#if APR_HAS_LDAP
/* only here until strdup is gone */
#include <string.h>
/* here till malloc is gone */
#include <stdlib.h>
static const unsigned long primes[] =
{
11,
19,
37,
73,
109,
163,
251,
367,
557,
823,
1237,
1861,
2777,
4177,
6247,
9371,
14057,
21089,
31627,
47431,
71143,
106721,
160073,
240101,
360163,
540217,
810343,
1215497,
1823231,
2734867,
4102283,
6153409,
9230113,
13845163,
0
};
void util_ald_free(util_ald_cache_t *cache, const void *ptr)
{
#if APR_HAS_SHARED_MEMORY
if (cache->rmm_addr) {
if (ptr)
/* Free in shared memory */
apr_rmm_free(cache->rmm_addr, apr_rmm_offset_get(cache->rmm_addr, (void *)ptr));
}
else {
if (ptr)
/* Cache shm is not used */
free((void *)ptr);
}
#else
if (ptr)
free((void *)ptr);
#endif
}
void *util_ald_alloc(util_ald_cache_t *cache, unsigned long size)
{
if (0 == size)
return NULL;
#if APR_HAS_SHARED_MEMORY
if (cache->rmm_addr) {
/* allocate from shared memory */
apr_rmm_off_t block = apr_rmm_calloc(cache->rmm_addr, size);
return block ? (void *)apr_rmm_addr_get(cache->rmm_addr, block) : NULL;
}
else {
/* Cache shm is not used */
return (void *)calloc(sizeof(char), size);
}
#else
return (void *)calloc(sizeof(char), size);
#endif
}
const char *util_ald_strdup(util_ald_cache_t *cache, const char *s)
{
#if APR_HAS_SHARED_MEMORY
if (cache->rmm_addr) {
/* allocate from shared memory */
apr_rmm_off_t block = apr_rmm_calloc(cache->rmm_addr, strlen(s)+1);
char *buf = block ? (char *)apr_rmm_addr_get(cache->rmm_addr, block) : NULL;
if (buf) {
strcpy(buf, s);
return buf;
}
else {
return NULL;
}
} else {
/* Cache shm is not used */
return strdup(s);
}
#else
return strdup(s);
#endif
}
/*
* Computes the hash on a set of strings. The first argument is the number
* of strings to hash, the rest of the args are strings.
* Algorithm taken from glibc.
*/
unsigned long util_ald_hash_string(int nstr, ...)
{
int i;
va_list args;
unsigned long h=0, g;
char *str, *p;
va_start(args, nstr);
for (i=0; i < nstr; ++i) {
str = va_arg(args, char *);
for (p = str; *p; ++p) {
h = ( h << 4 ) + *p;
if ( ( g = h & 0xf0000000 ) ) {
h = h ^ (g >> 24);
h = h ^ g;
}
}
}
va_end(args);
return h;
}
/*
Purges a cache that has gotten full. We keep track of the time that we
added the entry that made the cache 3/4 full, then delete all entries
that were added before that time. It's pretty simplistic, but time to
purge is only O(n), which is more important.
*/
void util_ald_cache_purge(util_ald_cache_t *cache)
{
unsigned long i;
util_cache_node_t *p, *q, **pp;
apr_time_t t;
if (!cache)
return;
cache->last_purge = apr_time_now();
cache->npurged = 0;
cache->numpurges++;
for (i=0; i < cache->size; ++i) {
pp = cache->nodes + i;
p = *pp;
while (p != NULL) {
if (p->add_time < cache->marktime) {
q = p->next;
(*cache->free)(cache, p->payload);
util_ald_free(cache, p);
cache->numentries--;
cache->npurged++;
p = *pp = q;
}
else {
pp = &(p->next);
p = *pp;
}
}
}
t = apr_time_now();
cache->avg_purgetime =
((t - cache->last_purge) + (cache->avg_purgetime * (cache->numpurges-1))) /
cache->numpurges;
}
/*
* create caches
*/
util_url_node_t *util_ald_create_caches(util_ldap_state_t *st, const char *url)
{
util_url_node_t curl, *newcurl = NULL;
util_ald_cache_t *search_cache;
util_ald_cache_t *compare_cache;
util_ald_cache_t *dn_compare_cache;
/* create the three caches */
search_cache = util_ald_create_cache(st,
util_ldap_search_node_hash,
util_ldap_search_node_compare,
util_ldap_search_node_copy,
util_ldap_search_node_free,
util_ldap_search_node_display);
compare_cache = util_ald_create_cache(st,
util_ldap_compare_node_hash,
util_ldap_compare_node_compare,
util_ldap_compare_node_copy,
util_ldap_compare_node_free,
util_ldap_compare_node_display);
dn_compare_cache = util_ald_create_cache(st,
util_ldap_dn_compare_node_hash,
util_ldap_dn_compare_node_compare,
util_ldap_dn_compare_node_copy,
util_ldap_dn_compare_node_free,
util_ldap_dn_compare_node_display);
/* check that all the caches initialised successfully */
if (search_cache && compare_cache && dn_compare_cache) {
/* The contents of this structure will be duplicated in shared
memory during the insert. So use stack memory rather than
pool memory to avoid a memory leak. */
memset (&curl, 0, sizeof(util_url_node_t));
curl.url = url;
curl.search_cache = search_cache;
curl.compare_cache = compare_cache;
curl.dn_compare_cache = dn_compare_cache;
newcurl = util_ald_cache_insert(st->util_ldap_cache, &curl);
}
return newcurl;
}
util_ald_cache_t *util_ald_create_cache(util_ldap_state_t *st,
unsigned long (*hashfunc)(void *),
int (*comparefunc)(void *, void *),
void * (*copyfunc)(util_ald_cache_t *cache, void *),
void (*freefunc)(util_ald_cache_t *cache, void *),
void (*displayfunc)(request_rec *r, util_ald_cache_t *cache, void *))
{
util_ald_cache_t *cache;
unsigned long i;
if (st->search_cache_size <= 0)
return NULL;
#if APR_HAS_SHARED_MEMORY
if (!st->cache_rmm) {
return NULL;
}
else {
apr_rmm_off_t block = apr_rmm_calloc(st->cache_rmm, sizeof(util_ald_cache_t));
cache = block ? (util_ald_cache_t *)apr_rmm_addr_get(st->cache_rmm, block) : NULL;
}
#else
cache = (util_ald_cache_t *)calloc(sizeof(util_ald_cache_t), 1);
#endif
if (!cache)
return NULL;
#if APR_HAS_SHARED_MEMORY
cache->rmm_addr = st->cache_rmm;
cache->shm_addr = st->cache_shm;
#endif
cache->maxentries = st->search_cache_size;
cache->numentries = 0;
cache->size = st->search_cache_size / 3;
if (cache->size < 64) cache->size = 64;
for (i = 0; primes[i] && primes[i] < cache->size; ++i) ;
cache->size = primes[i]? primes[i] : primes[i-1];
cache->nodes = (util_cache_node_t **)util_ald_alloc(cache, cache->size * sizeof(util_cache_node_t *));
if (!cache->nodes) {
util_ald_free(cache, cache);
return NULL;
}
for (i=0; i < cache->size; ++i)
cache->nodes[i] = NULL;
cache->hash = hashfunc;
cache->compare = comparefunc;
cache->copy = copyfunc;
cache->free = freefunc;
cache->display = displayfunc;
cache->fullmark = cache->maxentries / 4 * 3;
cache->marktime = 0;
cache->avg_purgetime = 0.0;
cache->numpurges = 0;
cache->last_purge = 0;
cache->npurged = 0;
cache->fetches = 0;
cache->hits = 0;
cache->inserts = 0;
cache->removes = 0;
return cache;
}
void util_ald_destroy_cache(util_ald_cache_t *cache)
{
unsigned long i;
util_cache_node_t *p, *q;
if (cache == NULL)
return;
for (i = 0; i < cache->size; ++i) {
p = cache->nodes[i];
q = NULL;
while (p != NULL) {
q = p->next;
(*cache->free)(cache, p->payload);
util_ald_free(cache, p);
p = q;
}
}
util_ald_free(cache, cache->nodes);
util_ald_free(cache, cache);
}
void *util_ald_cache_fetch(util_ald_cache_t *cache, void *payload)
{
int hashval;
util_cache_node_t *p;
if (cache == NULL)
return NULL;
cache->fetches++;
hashval = (*cache->hash)(payload) % cache->size;
for (p = cache->nodes[hashval];
p && !(*cache->compare)(p->payload, payload);
p = p->next) ;
if (p != NULL) {
cache->hits++;
return p->payload;
}
else {
return NULL;
}
}
/*
* Insert an item into the cache.
* *** Does not catch duplicates!!! ***
*/
void *util_ald_cache_insert(util_ald_cache_t *cache, void *payload)
{
int hashval;
util_cache_node_t *node;
/* sanity check */
if (cache == NULL || payload == NULL) {
return NULL;
}
/* check if we are full - if so, try purge */
if (cache->numentries >= cache->maxentries) {
util_ald_cache_purge(cache);
if (cache->numentries >= cache->maxentries) {
/* if the purge was not effective, we leave now to avoid an overflow */
return NULL;
}
}
/* should be safe to add an entry */
if ((node = (util_cache_node_t *)util_ald_alloc(cache, sizeof(util_cache_node_t))) == NULL) {
return NULL;
}
/* populate the entry */
cache->inserts++;
hashval = (*cache->hash)(payload) % cache->size;
node->add_time = apr_time_now();
node->payload = (*cache->copy)(cache, payload);
node->next = cache->nodes[hashval];
cache->nodes[hashval] = node;
/* if we reach the full mark, note the time we did so
* for the benefit of the purge function
*/
if (++cache->numentries == cache->fullmark) {
cache->marktime=apr_time_now();
}
return node->payload;
}
void util_ald_cache_remove(util_ald_cache_t *cache, void *payload)
{
int hashval;
util_cache_node_t *p, *q;
if (cache == NULL)
return;
cache->removes++;
hashval = (*cache->hash)(payload) % cache->size;
for (p = cache->nodes[hashval], q=NULL;
p && !(*cache->compare)(p->payload, payload);
p = p->next) {
q = p;
}
/* If p is null, it means that we couldn't find the node, so just return */
if (p == NULL)
return;
if (q == NULL) {
/* We found the node, and it's the first in the list */
cache->nodes[hashval] = p->next;
}
else {
/* We found the node and it's not the first in the list */
q->next = p->next;
}
(*cache->free)(cache, p->payload);
util_ald_free(cache, p);
cache->numentries--;
}
char *util_ald_cache_display_stats(request_rec *r, util_ald_cache_t *cache, char *name, char *id)
{
unsigned long i;
int totchainlen = 0;
int nchains = 0;
double chainlen;
util_cache_node_t *n;
char *buf, *buf2;
apr_pool_t *p = r->pool;
if (cache == NULL) {
return "";
}
for (i=0; i < cache->size; ++i) {
if (cache->nodes[i] != NULL) {
nchains++;
for (n = cache->nodes[i];
n != NULL && n != n->next;
n = n->next) {
totchainlen++;
}
}
}
chainlen = nchains? (double)totchainlen / (double)nchains : 0;
if (id) {
buf2 = apr_psprintf(p,
"<a href=\"%s?%s\">%s</a>",
r->uri,
id,
name);
}
else {
buf2 = name;
}
buf = apr_psprintf(p,
"<tr valign='top'>"
"<td nowrap>%s</td>"
"<td align='right' nowrap>%lu (%.0f%% full)</td>"
"<td align='right'>%.1f</td>"
"<td align='right'>%lu/%lu</td>"
"<td align='right'>%.0f%%</td>"
"<td align='right'>%lu/%lu</td>",
buf2,
cache->numentries,
(double)cache->numentries / (double)cache->maxentries * 100.0,
chainlen,
cache->hits,
cache->fetches,
(cache->fetches > 0 ? (double)(cache->hits) / (double)(cache->fetches) * 100.0 : 100.0),
cache->inserts,
cache->removes);
if (cache->numpurges) {
char str_ctime[APR_CTIME_LEN];
apr_ctime(str_ctime, cache->last_purge);
buf = apr_psprintf(p,
"%s"
"<td align='right'>%lu</td>\n"
"<td align='right' nowrap>%s</td>\n",
buf,
cache->numpurges,
str_ctime);
}
else {
buf = apr_psprintf(p,
"%s<td colspan='2' align='center'>(none)</td>\n",
buf);
}
buf = apr_psprintf(p, "%s<td align='right'>%.2g</td>\n</tr>", buf, cache->avg_purgetime);
return buf;
}
char *util_ald_cache_display(request_rec *r, util_ldap_state_t *st)
{
unsigned long i,j;
char *buf, *t1, *t2, *t3;
char *id1, *id2, *id3;
char *argfmt = "cache=%s&id=%d&off=%d";
char *scanfmt = "cache=%4s&id=%u&off=%u%1s";
apr_pool_t *pool = r->pool;
util_cache_node_t *p = NULL;
util_url_node_t *n = NULL;
util_ald_cache_t *util_ldap_cache = st->util_ldap_cache;
if (!util_ldap_cache) {
return "<tr valign='top'><td nowrap colspan=7>Cache has not been enabled/initialised.</td></tr>";
}
if (r->args && strlen(r->args)) {
char cachetype[5], lint[2];
unsigned int id, off;
char date_str[APR_CTIME_LEN+1];
if ((3 == sscanf(r->args, scanfmt, cachetype, &id, &off, lint)) &&
(id < util_ldap_cache->size)) {
if ((p = util_ldap_cache->nodes[id]) != NULL) {
n = (util_url_node_t *)p->payload;
buf = (char*)n->url;
}
else {
buf = "";
}
ap_rputs(apr_psprintf(r->pool,
"<p>\n"
"<table border='0'>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Cache Name:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%s (%s)</b></font></td>"
"</tr>\n"
"</table>\n</p>\n",
buf,
cachetype[0] == 'm'? "Main" :
(cachetype[0] == 's' ? "Search" :
(cachetype[0] == 'c' ? "Compares" : "DNCompares"))), r);
switch (cachetype[0]) {
case 'm':
if (util_ldap_cache->marktime) {
apr_ctime(date_str, util_ldap_cache->marktime);
}
else
date_str[0] = 0;
ap_rputs(apr_psprintf(r->pool,
"<p>\n"
"<table border='0'>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Size:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%ld</b></font></td>"
"</tr>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Max Entries:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%ld</b></font></td>"
"</tr>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b># Entries:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%ld</b></font></td>"
"</tr>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Full Mark:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%ld</b></font></td>"
"</tr>\n"
"<tr>\n"
"<td bgcolor='#000000'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Full Mark Time:</b></font></td>"
"<td bgcolor='#ffffff'><font size='-1' face='Arial,Helvetica' color='#000000'><b>%s</b></font></td>"
"</tr>\n"
"</table>\n</p>\n",
util_ldap_cache->size,
util_ldap_cache->maxentries,
util_ldap_cache->numentries,
util_ldap_cache->fullmark,
date_str), r);
ap_rputs("<p>\n"
"<table border='0'>\n"
"<tr bgcolor='#000000'>\n"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>LDAP URL</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Size</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Max Entries</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b># Entries</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Full Mark</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Full Mark Time</b></font></td>"
"</tr>\n", r
);
for (i=0; i < util_ldap_cache->size; ++i) {
for (p = util_ldap_cache->nodes[i]; p != NULL; p = p->next) {
(*util_ldap_cache->display)(r, util_ldap_cache, p->payload);
}
}
ap_rputs("</table>\n</p>\n", r);
break;
case 's':
ap_rputs("<p>\n"
"<table border='0'>\n"
"<tr bgcolor='#000000'>\n"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>LDAP Filter</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>User Name</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Last Bind</b></font></td>"
"</tr>\n", r
);
for (i=0; i < n->search_cache->size; ++i) {
for (p = n->search_cache->nodes[i]; p != NULL; p = p->next) {
(*n->search_cache->display)(r, n->search_cache, p->payload);
}
}
ap_rputs("</table>\n</p>\n", r);
break;
case 'c':
ap_rputs("<p>\n"
"<table border='0'>\n"
"<tr bgcolor='#000000'>\n"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>DN</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Attribute</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Value</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Last Compare</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Result</b></font></td>"
"</tr>\n", r
);
for (i=0; i < n->compare_cache->size; ++i) {
for (p = n->compare_cache->nodes[i]; p != NULL; p = p->next) {
(*n->compare_cache->display)(r, n->compare_cache, p->payload);
}
}
ap_rputs("</table>\n</p>\n", r);
break;
case 'd':
ap_rputs("<p>\n"
"<table border='0'>\n"
"<tr bgcolor='#000000'>\n"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Require DN</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Actual DN</b></font></td>"
"</tr>\n", r
);
for (i=0; i < n->dn_compare_cache->size; ++i) {
for (p = n->dn_compare_cache->nodes[i]; p != NULL; p = p->next) {
(*n->dn_compare_cache->display)(r, n->dn_compare_cache, p->payload);
}
}
ap_rputs("</table>\n</p>\n", r);
break;
default:
break;
}
}
else {
buf = "";
}
}
else {
ap_rputs("<p>\n"
"<table border='0'>\n"
"<tr bgcolor='#000000'>\n"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Cache Name</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Entries</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Avg. Chain Len.</b></font></td>"
"<td colspan='2'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Hits</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Ins/Rem</b></font></td>"
"<td colspan='2'><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Purges</b></font></td>"
"<td><font size='-1' face='Arial,Helvetica' color='#ffffff'><b>Avg Purge Time</b></font></td>"
"</tr>\n", r
);
id1 = apr_psprintf(pool, argfmt, "main", 0, 0);
buf = util_ald_cache_display_stats(r, st->util_ldap_cache, "LDAP URL Cache", id1);
for (i=0; i < util_ldap_cache->size; ++i) {
for (p = util_ldap_cache->nodes[i],j=0; p != NULL; p = p->next,j++) {
n = (util_url_node_t *)p->payload;
t1 = apr_psprintf(pool, "%s (Searches)", n->url);
t2 = apr_psprintf(pool, "%s (Compares)", n->url);
t3 = apr_psprintf(pool, "%s (DNCompares)", n->url);
id1 = apr_psprintf(pool, argfmt, "srch", i, j);
id2 = apr_psprintf(pool, argfmt, "cmpr", i, j);
id3 = apr_psprintf(pool, argfmt, "dncp", i, j);
buf = apr_psprintf(pool, "%s\n\n"
"%s\n\n"
"%s\n\n"
"%s\n\n",
buf,
util_ald_cache_display_stats(r, n->search_cache, t1, id1),
util_ald_cache_display_stats(r, n->compare_cache, t2, id2),
util_ald_cache_display_stats(r, n->dn_compare_cache, t3, id3)
);
}
}
ap_rputs(buf, r);
ap_rputs("</table>\n</p>\n", r);
}
return buf;
}
#endif /* APR_HAS_LDAP */