Refine LRU cache by clearing old objects

src/acl.c

@@ -56,6 +56,12 @@ remove_from_block_list(char *addr)
     return cache_remove(block_list, addr, addr_len);
 }
 
+void
+clear_block_list()
+{
+    cache_clear(block_list, 3600); // Clear items older than 1 hour
+}
+
 int
 check_block_list(char *addr, int err_level)
 {

src/acl.h

@@ -34,6 +34,7 @@
 
 int init_acl(const char *path);
 void free_acl(void);
+void clear_block_list(void);
 
 int acl_match_host(const char *ip);
 int acl_add_ip(const char *ip);

src/cache.c

@@ -94,7 +94,7 @@ cache_delete(struct cache *cache, int keep_data)
                 if (cache->free_cb) {
                     cache->free_cb(entry->data);
                 } else {
-                    ss_free(tmp->data);
+                    ss_free(entry->data);
                 }
             }
             ss_free(entry->key);
@@ -106,6 +106,45 @@ cache_delete(struct cache *cache, int keep_data)
     return 0;
 }
 
+/** Clear old cache object
+ *
+ *  @param cache
+ *  The cache object to clear
+ *
+ *  @param age
+ *  Clear only objects older than the age (sec)
+ *
+ *  @return EINVAL if cache is NULL, 0 otherwise
+ */
+int
+cache_clear(struct cache *cache, ev_tstamp age)
+{
+    struct cache_entry *entry, *tmp;
+
+    if (!cache) {
+        return EINVAL;
+    }
+
+    ev_tstamp now = ev_time();
+
+    HASH_ITER(hh, cache->entries, entry, tmp){
+        if (now - entry->ts > age) {
+            HASH_DEL(cache->entries, entry);
+            if (entry->data != NULL) {
+                if (cache->free_cb) {
+                    cache->free_cb(entry->data);
+                } else {
+                    ss_free(entry->data);
+                }
+            }
+            ss_free(entry->key);
+            ss_free(entry);
+        }
+    }
+
+    return 0;
+}
+
 /** Removes a cache entry
  *
  *  @param cache
@@ -179,6 +218,7 @@ cache_lookup(struct cache *cache, char *key, size_t key_len, void *result)
     HASH_FIND(hh, cache->entries, key, key_len, tmp);
     if (tmp) {
         HASH_DELETE(hh, cache->entries, tmp);
+        tmp->ts = ev_time();
         HASH_ADD_KEYPTR(hh, cache->entries, tmp->key, key_len, tmp);
         *dirty_hack = tmp->data;
     } else {
@@ -200,6 +240,7 @@ cache_key_exist(struct cache *cache, char *key, size_t key_len)
     HASH_FIND(hh, cache->entries, key, key_len, tmp);
     if (tmp) {
         HASH_DELETE(hh, cache->entries, tmp);
+        tmp->ts = ev_time();
         HASH_ADD_KEYPTR(hh, cache->entries, tmp->key, key_len, tmp);
         return 1;
     } else {
@@ -242,6 +283,7 @@ cache_insert(struct cache *cache, char *key, size_t key_len, void *data)
     entry->key = ss_malloc(key_len);
     memcpy(entry->key, key, key_len);
     entry->data = data;
+    entry->ts = ev_time();
     HASH_ADD_KEYPTR(hh, cache->entries, entry->key, key_len, entry);
 
     if (HASH_COUNT(cache->entries) >= cache->max_entries) {

src/cache.h

@@ -29,6 +29,7 @@
 #define _CACHE_
 
 #include "uthash.h"
+#include "ev.h"
 
 /**
  * A cache entry
@@ -36,6 +37,7 @@
 struct cache_entry {
     char *key;         /**<The key */
     void *data;        /**<Payload */
+    ev_tstamp ts;    /**<Timestamp */
     UT_hash_handle hh; /**<Hash Handle for uthash */
 };
 
@@ -48,12 +50,13 @@ struct cache {
     void (*free_cb) (void *element); /**<Callback function to free cache entries */
 };
 
-extern int cache_create(struct cache **dst, const size_t capacity,
+int cache_create(struct cache **dst, const size_t capacity,
                         void (*free_cb)(void *element));
-extern int cache_delete(struct cache *cache, int keep_data);
-extern int cache_lookup(struct cache *cache, char *key, size_t key_len, void *result);
-extern int cache_insert(struct cache *cache, char *key, size_t key_len, void *data);
-extern int cache_remove(struct cache *cache, char *key, size_t key_len);
-extern int cache_key_exist(struct cache *cache, char *key, size_t key_len);
+int cache_delete(struct cache *cache, int keep_data);
+int cache_clear(struct cache *cache, ev_tstamp age);
+int cache_lookup(struct cache *cache, char *key, size_t key_len, void *result);
+int cache_insert(struct cache *cache, char *key, size_t key_len, void *data);
+int cache_remove(struct cache *cache, char *key, size_t key_len);
+int cache_key_exist(struct cache *cache, char *key, size_t key_len);
 
 #endif

src/encrypt.c

@@ -1392,7 +1392,7 @@ enc_key_init(int method, const char *pass)
     if (sodium_init() == -1) {
         FATAL("Failed to initialize sodium");
     }
-    
+
     if (method == SALSA20 || method == CHACHA20 || method == CHACHA20IETF) {
         // Fake cipher
         cipher = (cipher_kt_t *)&cipher_info;
@@ -1469,8 +1469,8 @@ enc_init(const char *pass, const char *method)
                 break;
             }
         if (m >= CIPHER_NUM) {
-            LOGE("Invalid cipher name: %s, use table instead", method);
-            m = TABLE;
+            LOGE("Invalid cipher name: %s, use rc4-md5 instead", method);
+            m = RC4_MD5;
         }
     }
     if (m == TABLE) {

src/local.c

@@ -1316,7 +1316,7 @@ main(int argc, char **argv)
     }
 
     if (method == NULL) {
-        method = "table";
+        method = "rc4-md5";
     }
 
     if (timeout == NULL) {

src/redir.c

@@ -910,6 +910,10 @@ main(int argc, char **argv)
         exit(EXIT_FAILURE);
     }
 
+    if (method == NULL) {
+        method = "rc4-md5";
+    }
+
     if (timeout == NULL) {
         timeout = "60";
     }

src/server.c

@@ -91,6 +91,7 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents);
 static void remote_recv_cb(EV_P_ ev_io *w, int revents);
 static void remote_send_cb(EV_P_ ev_io *w, int revents);
 static void server_timeout_cb(EV_P_ ev_timer *watcher, int revents);
+static void block_list_clear_cb(EV_P_ ev_timer *watcher, int revents);
 
 static remote_t *new_remote(int fd);
 static server_t *new_server(int fd, listen_ctx_t *listener);
@@ -127,6 +128,7 @@ static char *manager_address = NULL;
 uint64_t tx                  = 0;
 uint64_t rx                  = 0;
 ev_timer stat_update_watcher;
+ev_timer block_list_watcher;
 
 static struct cork_dllist connections;
 
@@ -974,6 +976,12 @@ server_send_cb(EV_P_ ev_io *w, int revents)
     }
 }
 
+static void
+block_list_clear_cb(EV_P_ ev_timer *watcher, int revents)
+{
+    clear_block_list();
+}
+
 static void
 server_timeout_cb(EV_P_ ev_timer *watcher, int revents)
 {
@@ -1653,7 +1661,7 @@ main(int argc, char **argv)
     }
 
     if (method == NULL) {
-        method = "table";
+        method = "rc4-md5";
     }
 
     if (timeout == NULL) {
@@ -1793,6 +1801,9 @@ main(int argc, char **argv)
         ev_timer_start(EV_DEFAULT, &stat_update_watcher);
     }
 
+    ev_timer_init(&block_list_watcher, block_list_clear_cb, UPDATE_INTERVAL, UPDATE_INTERVAL);
+    ev_timer_start(EV_DEFAULT, &block_list_watcher);
+
     // setuid
     if (user != NULL) {
         run_as(user);
@@ -1811,6 +1822,7 @@ main(int argc, char **argv)
     if (manager_address != NULL) {
         ev_timer_stop(EV_DEFAULT, &stat_update_watcher);
     }
+    ev_timer_stop(EV_DEFAULT, &block_list_watcher);
 
     // Clean up
     for (int i = 0; i <= server_num; i++) {

src/tunnel.c

@@ -909,6 +909,10 @@ main(int argc, char **argv)
         exit(EXIT_FAILURE);
     }
 
+    if (method == NULL) {
+        method = "rc4-md5";
+    }
+
     if (timeout == NULL) {
         timeout = "60";
     }