ftp: fix direction of expectation for STOR command

Fix direction in active mode.

diff --git a/src/app-layer-ftp.c b/src/app-layer-ftp.c
index 8633bc37c3588dbf93565fef495ce7108c55b2b7..2810475d2b897085e4f0ca884f6b74c54f815e47 100644 (file)
--- a/src/app-layer-ftp.c
+++ b/src/app-layer-ftp.c
@@ -592,6 +592,16 @@ static AppLayerResult FTPParseRequest(Flow *f, void *ftp_state,
         tx->request_length = CopyCommandLine(&tx->request,
                 state->current_line, state->current_line_len);
 
+        /* change direction (default to server) so expectation will handle
+         * the correct message when expectation will match.
+         * For ftp active mode, data connection direction is opposite to
+         * control direction.
+         */
+        if ((state->active && state->command == FTP_COMMAND_STOR) ||
+                (!state->active && state->command == FTP_COMMAND_RETR)) {
+            direction = STREAM_TOCLIENT;
+        }
+
         switch (state->command) {
             case FTP_COMMAND_EPRT:
                 // fallthrough
@@ -616,10 +626,6 @@ static AppLayerResult FTPParseRequest(Flow *f, void *ftp_state,
                 state->port_line_len = state->current_line_len;
                 break;
             case FTP_COMMAND_RETR:
-                /* change direction (default to server) so expectation will handle
-                 * the correct message when expectation will match.
-                 */
-                direction = STREAM_TOCLIENT;
                 // fallthrough
             case FTP_COMMAND_STOR: {
                     /* Ensure that there is a negotiated dyn port and a file
@@ -647,8 +653,7 @@ static AppLayerResult FTPParseRequest(Flow *f, void *ftp_state,
                     memcpy(data->file_name, state->current_line + 5, file_name_len);
                     data->cmd = state->command;
                     data->flow_id = FlowGetId(f);
-                    int ret = AppLayerExpectationCreate(f,
-                                            state->active ? STREAM_TOSERVER : direction,
+                    int ret = AppLayerExpectationCreate(f, direction,
                                             0, state->dyn_port, ALPROTO_FTPDATA, data);
                     if (ret == -1) {
                         FtpTransferCmdFree(data);