cleanups and several fixes(and speedups) in the resume DB

1 files changed, 69 insertions, 26 deletions

diff --git a/lib/gnutls_db.c b/lib/gnutls_db.c
index 6e1545e031..10cf405521 100644
--- a/lib/gnutls_db.c
+++ b/lib/gnutls_db.c
@@ -18,12 +18,21 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 
+/* This file contains functions that manipulate a database
+ * for resumed sessions. 
+ */
 #include <defines.h>
 #include "gnutls_int.h"
 #include "gnutls_errors.h"
 #include "gnutls_session.h"
+#include "debug.h"
+
 #ifdef HAVE_LIBGDBM
-#include <gdbm.h>
+# define GNUTLS_DBF state->gnutls_internals.db_reader
+# define GNUTLS_DBNAME state->gnutls_internals.db_name
+# define REOPEN_DB() if (GNUTLS_DBF!=NULL) \
+	gdbm_close( GNUTLS_DBF); \
+	GNUTLS_DBF = gdbm_open(GNUTLS_DBNAME, 0, GDBM_READER, 0600, NULL);
 #endif
 
 int gnutls_set_cache_expiration( GNUTLS_STATE state, int seconds) {
@@ -31,12 +40,32 @@ int gnutls_set_cache_expiration( GNUTLS_STATE state, int seconds) {
 	return 0;
 }
 
+/* creates the database specified by filename, 
+ * and opens it for reading.
+ */
 int gnutls_set_db_name( GNUTLS_STATE state, char* filename) {
 #ifdef HAVE_LIBGDBM
+GDBM_FILE dbf;
 
-	if (state->gnutls_internals.db_name!=NULL)
-		gnutls_free(state->gnutls_internals.db_name);
-	state->gnutls_internals.db_name = strdup(filename);
+	if (filename==NULL) return 0;
+
+	/* deallocate previous name */
+	if (GNUTLS_DBNAME!=NULL)
+		gnutls_free(GNUTLS_DBNAME);
+
+	/* set name */
+	GNUTLS_DBNAME = strdup(filename);
+	if (GNUTLS_DBNAME==NULL) return GNUTLS_E_MEMORY_ERROR;
+
+	/* create if it does not exist 
+	 */
+	dbf = gdbm_open( filename, 0, GDBM_WRCREAT, 0600, NULL);
+	if (dbf==NULL) return GNUTLS_E_DB_ERROR;
+	gdbm_close(dbf);
+
+	/* open for reader */
+	GNUTLS_DBF = gdbm_open(GNUTLS_DBNAME, 0, GDBM_READER, 0600, NULL);
+	if (GNUTLS_DBF==NULL) return GNUTLS_E_DB_ERROR;
 
 	return 0;
 #else
@@ -44,13 +73,18 @@ int gnutls_set_db_name( GNUTLS_STATE state, char* filename) {
 #endif
 }
 
+
+/* This function removes expired and invalid sessions from the
+ * database
+ */
 int gnutls_clean_db( GNUTLS_STATE state) {
 #ifdef HAVE_LIBGDBM
 GDBM_FILE dbf;
+int ret;
 datum key;
 time_t timestamp;
 
-	dbf = gdbm_open(state->gnutls_internals.db_name, 0, GDBM_WRCREAT, 0600, NULL);
+	dbf = gdbm_open(GNUTLS_DBNAME, 0, GDBM_WRITER, 0600, NULL);
 	if (dbf==NULL) return GNUTLS_E_AGAIN;
 	key = gdbm_firstkey(dbf);
 
@@ -66,8 +100,13 @@ time_t timestamp;
 		free(key.dptr);
 		key = gdbm_nextkey(dbf, key);
 	}
+	ret = gdbm_reorganize(dbf);
+	
 	gdbm_close(dbf);
-
+	REOPEN_DB();
+	
+	if (ret!=0) return GNUTLS_E_DB_ERROR;
+		
 	return 0;
 #else
 	return GNUTLS_E_UNIMPLEMENTED_FEATURE;
@@ -83,55 +122,59 @@ datum key = { state->security_parameters.session_id, state->security_parameters.
 datum content;
 int ret = 0;
 
-	if (state->gnutls_internals.resumable==RESUME_FALSE) {
+	if (state->gnutls_internals.resumable==RESUME_FALSE) 
 		return GNUTLS_E_INVALID_SESSION;
-	}
-	if (state->gnutls_internals.db_name==NULL) {
+
+	if (GNUTLS_DBNAME==NULL)
 		return GNUTLS_E_DB_ERROR;
-	}
-	if (state->security_parameters.session_id==NULL || state->security_parameters.session_id_size==0) {
+
+	if (state->security_parameters.session_id==NULL || state->security_parameters.session_id_size==0)
 		return GNUTLS_E_INVALID_SESSION;
-	}
+
 
 /* allocate space for data */
-	content.dptr = gnutls_malloc( sizeof(SecurityParameters) + state->gnutls_key->auth_info_size );
 	content.dsize = sizeof(SecurityParameters) + state->gnutls_key->auth_info_size;
+	content.dptr = gnutls_malloc( content.dsize);
+	if (content.dptr==NULL) return GNUTLS_E_MEMORY_ERROR;
 
 /* copy data */
 	memcpy( content.dptr, (void*)&state->security_parameters, sizeof(SecurityParameters));
 	memcpy( &content.dptr[sizeof(SecurityParameters)], state->gnutls_key->auth_info,  state->gnutls_key->auth_info_size);
 
-	dbf = gdbm_open(state->gnutls_internals.db_name, 0, GDBM_WRCREAT|GDBM_FAST, 0600, NULL);
-	if (dbf==NULL) return GNUTLS_E_AGAIN;
+	dbf = gdbm_open(GNUTLS_DBNAME, 0, GDBM_WRITER, 0600, NULL);
+	if (dbf==NULL) {
+		gnutls_free(content.dptr);
+		/* cannot open db for writing. This may happen if multiple
+		 * instances try to write. 
+		 */
+		return GNUTLS_E_AGAIN;
+	}
 	ret = gdbm_store( dbf, key, content, GDBM_INSERT);
 
 	gnutls_free( content.dptr);
 
 	gdbm_close(dbf);
-
 	return (ret == 0 ? ret : GNUTLS_E_UNKNOWN_ERROR);
 #else
 	return GNUTLS_E_UNIMPLEMENTED_FEATURE;
 #endif
 }
 
-
 int _gnutls_server_restore_session( GNUTLS_STATE state, uint8* session_id, int session_id_size)
 {
 #ifdef HAVE_LIBGDBM
-GDBM_FILE dbf;
 datum content;
 datum key = { session_id, session_id_size};
 int ret;
 
-	if (state->gnutls_internals.db_name==NULL) return GNUTLS_E_DB_ERROR;
+	if (GNUTLS_DBNAME==NULL) return GNUTLS_E_DB_ERROR;
 
-	dbf = gdbm_open(state->gnutls_internals.db_name, 0, GDBM_READER|GDBM_FAST, 0600, NULL);
-	if (dbf==NULL) return GNUTLS_E_AGAIN;
-	content = gdbm_fetch( dbf, key);
-	gdbm_close(dbf);
+	if (GNUTLS_DBF==NULL) return GNUTLS_E_DB_ERROR;
+	content = gdbm_fetch( GNUTLS_DBF, key);
 
-	if (content.dptr==NULL) return GNUTLS_E_INVALID_SESSION;
+	if (content.dptr==NULL) {
+		return GNUTLS_E_INVALID_SESSION;
+	}
 
 	/* expiration check is performed inside */
 	ret = gnutls_set_current_session( state, content.dptr, content.dsize);
@@ -150,9 +193,9 @@ GDBM_FILE dbf;
 datum key = { session_id, session_id_size};
 int ret;
 
-	if (state->gnutls_internals.db_name==NULL) return GNUTLS_E_DB_ERROR;
+	if (GNUTLS_DBNAME==NULL) return GNUTLS_E_DB_ERROR;
 
-	dbf = gdbm_open(state->gnutls_internals.db_name, 0, GDBM_READER|GDBM_FAST, 0600, NULL);
+	dbf = gdbm_open(GNUTLS_DBNAME, 0, GDBM_READER, 0600, NULL);
 	if (dbf==NULL) return GNUTLS_E_AGAIN;
 	ret = gdbm_delete( dbf, key);
 	gdbm_close(dbf);