[ftp] Cope with RETR completion prior to all data received

Based on a patch contributed by Sergey Vlasov <vsu@altlinux.ru> :

  In my testing with "qemu -net user" the 226 response to RETR was
  often received earlier than final packets of the data connection;
  this caused the received file to become truncated without any error
  indication.  Fix this by adding an intermediate state FTP_TRANSFER
  between FTP_RETR and FTP_QUIT, so that the transfer is considered to
  be complete only when both the end of data connection is encountered
  and the final reply to the RETR command is received.

diff --git a/src/net/tcp/ftp.c b/src/net/tcp/ftp.c
index ffb2fbffcfc7a117e1f965846415177d8facfe5d..9a12064e169c0b3abc0d774a9804a1d16886d16a 100644 (file)
--- a/src/net/tcp/ftp.c
+++ b/src/net/tcp/ftp.c
@@ -35,6 +35,7 @@ enum ftp_state {
        FTP_TYPE,
        FTP_PASV,
        FTP_RETR,
+       FTP_WAIT,
        FTP_QUIT,
        FTP_DONE,
 };
@@ -116,14 +117,15 @@ static void ftp_done ( struct ftp_request *ftp, int rc ) {
  * snprintf() call.
  */
 static const char * ftp_strings[] = {
-       [FTP_CONNECT]   = "",
+       [FTP_CONNECT]   = NULL,
        [FTP_USER]      = "USER anonymous\r\n",
        [FTP_PASS]      = "PASS etherboot@etherboot.org\r\n",
        [FTP_TYPE]      = "TYPE I\r\n",
        [FTP_PASV]      = "PASV\r\n",
-       [FTP_RETR]      = "RETR %s\r\n", 
+       [FTP_RETR]      = "RETR %s\r\n",
+       [FTP_WAIT]      = NULL,
        [FTP_QUIT]      = "QUIT\r\n",
-       [FTP_DONE]      = "",
+       [FTP_DONE]      = NULL,
 };
 
 /**
@@ -169,6 +171,27 @@ static void ftp_parse_value ( char **text, uint8_t *value, size_t len ) {
        } while ( --len );
 }
 
+/**
+ * Move to next state and send the appropriate FTP control string
+ *
+ * @v ftp              FTP request
+ *
+ */
+static void ftp_next_state ( struct ftp_request *ftp ) {
+
+       /* Move to next state */
+       if ( ftp->state < FTP_DONE )
+               ftp->state++;
+
+       /* Send control string if needed */
+       if ( ftp_strings[ftp->state] != NULL ) {
+               DBGC ( ftp, "FTP %p sending ", ftp );
+               DBGC ( ftp, ftp_strings[ftp->state], ftp->uri->path );
+               xfer_printf ( &ftp->control, ftp_strings[ftp->state],
+                             ftp->uri->path );
+       }       
+}
+
 /**
  * Handle an FTP control channel response
  *
@@ -223,17 +246,9 @@ static void ftp_reply ( struct ftp_request *ftp ) {
                }
        }
 
-       /* Move to next state */
-       if ( ftp->state < FTP_DONE )
-               ftp->state++;
-
-       /* Send control string */
-       if ( ftp->state < FTP_DONE ) {
-               DBGC ( ftp, "FTP %p sending ", ftp );
-               DBGC ( ftp, ftp_strings[ftp->state], ftp->uri->path );
-               xfer_printf ( &ftp->control, ftp_strings[ftp->state],
-                             ftp->uri->path );
-       }
+       /* Move to next state and send control string */
+       ftp_next_state ( ftp );
+       
 }
 
 /**
@@ -331,8 +346,11 @@ static void ftp_data_closed ( struct xfer_interface *data, int rc ) {
               ftp, strerror ( rc ) );
        
        /* If there was an error, close control channel and record status */
-       if ( rc )
+       if ( rc ) {
                ftp_done ( ftp, rc );
+       } else {
+               ftp_next_state ( ftp );
+       }
 }
 
 /**