ssl,dtls: split init/cleanup routines

Minor functional change: instead of an empty hash table, now the
ssl_session_hash and ssl_crandom_hash structures point will be set to
NULL when files are closed.

API change: drop the ssl_keylog_file parameter from ssl_common_init,
add a new ssl_common_cleanup parameter instead.

Change-Id: I65efe71f8347fe9685359f8ed70cfb9673712421
Reviewed-on: https://code.wireshark.org/review/9226
Reviewed-by: Michael Mann <mmann78@netscape.net>

epan/dissectors/packet-dtls.c

@@ -184,7 +184,7 @@ dtls_init(void)
   module_t *dtls_module = prefs_find_module("dtls");
   pref_t   *keys_list_pref;
 
-  ssl_common_init(&dtls_master_key_map, &dtls_keylog_file,
+  ssl_common_init(&dtls_master_key_map,
                   &dtls_decrypted_data, &dtls_compressed_data);
   reassembly_table_init (&dtls_reassembly_table, &addresses_ports_reassembly_table_functions);
 
@@ -197,6 +197,14 @@ dtls_init(void)
   }
 }
 
+static void
+dtls_cleanup(void)
+{
+  reassembly_table_destroy(&dtls_reassembly_table);
+  ssl_common_cleanup(&dtls_master_key_map, &dtls_keylog_file,
+                     &dtls_decrypted_data, &dtls_compressed_data);
+}
+
 /* parse dtls related preferences (private keys and ports association strings) */
 static void
 dtls_parse_uat(void)
@@ -1934,6 +1942,7 @@ proto_register_dtls(void)
   dtls_associations = g_tree_new(ssl_association_cmp);
 
   register_init_routine(dtls_init);
+  register_cleanup_routine(dtls_cleanup);
   ssl_lib_init();
   dtls_tap = register_tap("dtls");
   ssl_debug_printf("proto_register_dtls: registered tap %s:%d\n",

epan/dissectors/packet-ssl-utils.c

@@ -4367,34 +4367,28 @@ ssl_get_data_info(int proto, packet_info *pinfo, gint key)
 
 /* initialize/reset per capture state data (ssl sessions cache) */
 void
-ssl_common_init(ssl_master_key_map_t *mk_map, FILE **ssl_keylog_file,
+ssl_common_init(ssl_master_key_map_t *mk_map,
                 StringInfo *decrypted_data, StringInfo *compressed_data)
 {
-    if (mk_map->session)
-        g_hash_table_remove_all(mk_map->session);
-    else
-        mk_map->session = g_hash_table_new(ssl_hash, ssl_equal);
+    mk_map->session = g_hash_table_new(ssl_hash, ssl_equal);
+    mk_map->crandom = g_hash_table_new(ssl_hash, ssl_equal);
+    mk_map->pre_master = g_hash_table_new(ssl_hash, ssl_equal);
+    mk_map->pms = g_hash_table_new(ssl_hash, ssl_equal);
+    ssl_data_alloc(decrypted_data, 32);
+    ssl_data_alloc(compressed_data, 32);
+}
 
-    if (mk_map->crandom)
-        g_hash_table_remove_all(mk_map->crandom);
-    else
-        mk_map->crandom = g_hash_table_new(ssl_hash, ssl_equal);
-
-    if (mk_map->pre_master)
-        g_hash_table_remove_all(mk_map->pre_master);
-    else
-        mk_map->pre_master = g_hash_table_new(ssl_hash, ssl_equal);
-
-    if (mk_map->pms)
-        g_hash_table_remove_all(mk_map->pms);
-    else
-        mk_map->pms = g_hash_table_new(ssl_hash, ssl_equal);
+void
+ssl_common_cleanup(ssl_master_key_map_t *mk_map, FILE **ssl_keylog_file,
+                   StringInfo *decrypted_data, StringInfo *compressed_data)
+{
+    g_hash_table_destroy(mk_map->session);
+    g_hash_table_destroy(mk_map->crandom);
+    g_hash_table_destroy(mk_map->pre_master);
+    g_hash_table_destroy(mk_map->pms);
 
     g_free(decrypted_data->data);
-    ssl_data_alloc(decrypted_data, 32);
-
     g_free(compressed_data->data);
-    ssl_data_alloc(compressed_data, 32);
 
     /* close the previous keylog file now that the cache are cleared, this
      * allows the cache to be filled with the full keylog file contents. */

epan/dissectors/packet-ssl-utils.h

@@ -601,8 +601,11 @@ ssl_get_data_info(int proto, packet_info *pinfo, gint key);
 
 /* initialize/reset per capture state data (ssl sessions cache) */
 extern void
-ssl_common_init(ssl_master_key_map_t *master_key_map, FILE **ssl_keylog_file,
+ssl_common_init(ssl_master_key_map_t *master_key_map,
                 StringInfo *decrypted_data, StringInfo *compressed_data);
+extern void
+ssl_common_cleanup(ssl_master_key_map_t *master_key_map, FILE **ssl_keylog_file,
+                   StringInfo *decrypted_data, StringInfo *compressed_data);
 
 /* tries to update the secrets cache from the given filename */
 extern void

epan/dissectors/packet-ssl.c

@@ -333,12 +333,6 @@ void proto_reg_handoff_ssl(void);
 /* Desegmentation of SSL streams */
 /* table to hold defragmented SSL streams */
 static reassembly_table ssl_reassembly_table;
-static void
-ssl_fragment_init(void)
-{
-    reassembly_table_init(&ssl_reassembly_table,
-                          &addresses_ports_reassembly_table_functions);
-}
 
 /* initialize/reset per capture state data (ssl sessions cache) */
 static void
@@ -347,9 +341,10 @@ ssl_init(void)
     module_t *ssl_module = prefs_find_module("ssl");
     pref_t   *keys_list_pref;
 
-    ssl_common_init(&ssl_master_key_map, &ssl_keylog_file,
+    ssl_common_init(&ssl_master_key_map,
                     &ssl_decrypted_data, &ssl_compressed_data);
-    ssl_fragment_init();
+    reassembly_table_init(&ssl_reassembly_table,
+                          &addresses_ports_reassembly_table_functions);
     ssl_debug_flush();
 
     /* for "Export SSL Session Keys" */
@@ -365,6 +360,19 @@ ssl_init(void)
     }
 }
 
+static void
+ssl_cleanup(void)
+{
+    reassembly_table_destroy(&ssl_reassembly_table);
+    ssl_common_cleanup(&ssl_master_key_map, &ssl_keylog_file,
+                       &ssl_decrypted_data, &ssl_compressed_data);
+
+    /* should not be needed since the UI code prevents this from being accessed
+     * when no file is open. Clear it anyway just to be sure. */
+    ssl_session_hash = NULL;
+    ssl_crandom_hash = NULL;
+}
+
 /* parse ssl related preferences (private keys and ports association strings) */
 static void
 ssl_parse_uat(void)
@@ -4208,6 +4216,7 @@ proto_register_ssl(void)
     ssl_associations = g_tree_new(ssl_association_cmp);
 
     register_init_routine(ssl_init);
+    register_cleanup_routine(ssl_cleanup);
     ssl_lib_init();
     ssl_tap = register_tap("ssl");
     ssl_debug_printf("proto_register_ssl: registered tap %s:%d\n",