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-rw-r--r--src/postscreen/postscreen_dict.c182
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diff --git a/src/postscreen/postscreen_dict.c b/src/postscreen/postscreen_dict.c
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+/*++
+/* NAME
+/* postscreen_dict 3
+/* SUMMARY
+/* postscreen table access wrappers
+/* SYNOPSIS
+/* #include <postscreen.h>
+/*
+/* int psc_addr_match_list_match(match_list, client_addr)
+/* ADDR_MATCH_LIST *match_list;
+/* const char *client_addr;
+/*
+/* const char *psc_cache_lookup(DICT_CACHE *cache, const char *key)
+/* DICT_CACHE *cache;
+/* const char *key;
+/*
+/* void psc_cache_update(cache, key, value)
+/* DICT_CACHE *cache;
+/* const char *key;
+/* const char *value;
+/*
+/* void psc_dict_get(dict, key)
+/* DICT *dict;
+/* const char *key;
+/*
+/* void psc_maps_find(maps, key, flags)
+/* MAPS *maps;
+/* const char *key;
+/* int flags;
+/* DESCRIPTION
+/* This module implements wrappers around time-critical table
+/* access functions. The functions log a warning when table
+/* access takes a non-trivial amount of time.
+/*
+/* psc_addr_match_list_match() is a wrapper around
+/* addr_match_list_match().
+/*
+/* psc_cache_lookup() and psc_cache_update() are wrappers around
+/* the corresponding dict_cache() methods.
+/*
+/* psc_dict_get() and psc_maps_find() are wrappers around
+/* dict_get() and maps_find(), respectively.
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <dict.h>
+
+/* Global library. */
+
+#include <maps.h>
+
+/* Application-specific. */
+
+#include <postscreen.h>
+
+ /*
+ * Monitor time-critical operations.
+ *
+ * XXX Averaging support was added during a stable release candidate, so it
+ * provides only the absolute minimum necessary. A complete implementation
+ * should maintain separate statistics for each table, and it should not
+ * complain when the access latency is less than the time between accesses.
+ */
+#define PSC_GET_TIME_BEFORE_LOOKUP { \
+ struct timeval _before, _after; \
+ DELTA_TIME _delta; \
+ double _new_delta_ms; \
+ GETTIMEOFDAY(&_before);
+
+#define PSC_DELTA_MS(d) ((d).dt_sec * 1000.0 + (d).dt_usec / 1000.0)
+
+#define PSC_AVERAGE(new, old) (0.1 * (new) + 0.9 * (old))
+
+#ifndef PSC_THRESHOLD_MS
+#define PSC_THRESHOLD_MS 100 /* nag if latency > 100ms */
+#endif
+
+#ifndef PSC_WARN_LOCKOUT_S
+#define PSC_WARN_LOCKOUT_S 60 /* don't nag for 60s */
+#endif
+
+ /*
+ * Shared warning lock, so that we don't spam the logfile when the system
+ * becomes slow.
+ */
+static time_t psc_last_warn = 0;
+
+#define PSC_CHECK_TIME_AFTER_LOOKUP(table, action, average) \
+ GETTIMEOFDAY(&_after); \
+ PSC_CALC_DELTA(_delta, _after, _before); \
+ _new_delta_ms = PSC_DELTA_MS(_delta); \
+ if ((average = PSC_AVERAGE(_new_delta_ms, average)) > PSC_THRESHOLD_MS \
+ && psc_last_warn < _after.tv_sec - PSC_WARN_LOCKOUT_S) { \
+ msg_warn("%s: %s %s average delay is %.0f ms", \
+ myname, (table), (action), average); \
+ psc_last_warn = _after.tv_sec; \
+ } \
+}
+
+/* psc_addr_match_list_match - time-critical address list lookup */
+
+int psc_addr_match_list_match(ADDR_MATCH_LIST *addr_list,
+ const char *addr_str)
+{
+ const char *myname = "psc_addr_match_list_match";
+ int result;
+ static double latency_ms;
+
+ PSC_GET_TIME_BEFORE_LOOKUP;
+ result = addr_match_list_match(addr_list, addr_str);
+ PSC_CHECK_TIME_AFTER_LOOKUP("address list", "lookup", latency_ms);
+ return (result);
+}
+
+/* psc_cache_lookup - time-critical cache lookup */
+
+const char *psc_cache_lookup(DICT_CACHE *cache, const char *key)
+{
+ const char *myname = "psc_cache_lookup";
+ const char *result;
+ static double latency_ms;
+
+ PSC_GET_TIME_BEFORE_LOOKUP;
+ result = dict_cache_lookup(cache, key);
+ PSC_CHECK_TIME_AFTER_LOOKUP(dict_cache_name(cache), "lookup", latency_ms);
+ return (result);
+}
+
+/* psc_cache_update - time-critical cache update */
+
+void psc_cache_update(DICT_CACHE *cache, const char *key, const char *value)
+{
+ const char *myname = "psc_cache_update";
+ static double latency_ms;
+
+ PSC_GET_TIME_BEFORE_LOOKUP;
+ dict_cache_update(cache, key, value);
+ PSC_CHECK_TIME_AFTER_LOOKUP(dict_cache_name(cache), "update", latency_ms);
+}
+
+/* psc_dict_get - time-critical table lookup */
+
+const char *psc_dict_get(DICT *dict, const char *key)
+{
+ const char *myname = "psc_dict_get";
+ const char *result;
+ static double latency_ms;
+
+ PSC_GET_TIME_BEFORE_LOOKUP;
+ result = dict_get(dict, key);
+ PSC_CHECK_TIME_AFTER_LOOKUP(dict->name, "lookup", latency_ms);
+ return (result);
+}
+
+/* psc_maps_find - time-critical table lookup */
+
+const char *psc_maps_find(MAPS *maps, const char *key, int flags)
+{
+ const char *myname = "psc_maps_find";
+ const char *result;
+ static double latency_ms;
+
+ PSC_GET_TIME_BEFORE_LOOKUP;
+ result = maps_find(maps, key, flags);
+ PSC_CHECK_TIME_AFTER_LOOKUP(maps->title, "lookup", latency_ms);
+ return (result);
+}