bgpd: add flowspec utilities to decode, convert fs nlri

The FS nlri is depicted so as to be able to be in readable format,
either by human, or by some other ( remote daemon ?).
This work is a derived work from [0]. Initially done for validation
only, this work is extended.
The FS NLRI is able to decode addresses, numbers ( protocols, ports,
tcp values) combined ( or not) with operators. This makes possible
to have a NLRI entry for a set of ports, and/or for an other set of
value of port.
This implementation mainly brings the API visible. The API should be
consistent across the various usages.

[0] https://github.com/chinatelecom-sdn-group/quagga_flowspec/

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
Signed-off-by: jaydom <chinatelecom-sdn-group@github.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/bgpd/bgp_flowspec_util.h b/bgpd/bgp_flowspec_util.h
new file mode 100644
index 000000000..55a464a71
--- /dev/null
+++ b/bgpd/bgp_flowspec_util.h
@@ -0,0 +1,53 @@
+/* BGP Flowspec header for utilities
+ * Copyright (C) 2018 6WIND
+ *
+ * FRRouting is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * FRRouting is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef _FRR_BGP_FLOWSPEC_UTIL_H
+#define _FRR_BGP_FLOWSPEC_UTIL_H
+
+#include "zclient.h"
+
+#define BGP_FLOWSPEC_STRING_DISPLAY_MAX 512
+
+enum bgp_flowspec_util_nlri_t {
+	BGP_FLOWSPEC_VALIDATE_ONLY = 0,
+	BGP_FLOWSPEC_RETURN_STRING = 1,
+	BGP_FLOWSPEC_CONVERT_TO_NON_OPAQUE = 2
+};
+
+
+extern int bgp_flowspec_op_decode(enum bgp_flowspec_util_nlri_t type,
+				  uint8_t *nlri_ptr,
+				  uint32_t max_len,
+				  void *result, int *error);
+
+extern int bgp_flowspec_ip_address(enum bgp_flowspec_util_nlri_t type,
+				   uint8_t *nlri_ptr,
+				   uint32_t max_len,
+				   void *result, int *error);
+
+extern int bgp_flowspec_tcpflags_decode(enum bgp_flowspec_util_nlri_t type,
+					uint8_t *nlri_ptr,
+					uint32_t max_len,
+					void *result, int *error);
+
+extern int bgp_flowspec_fragment_type_decode(enum bgp_flowspec_util_nlri_t type,
+					     uint8_t *nlri_ptr,
+					     uint32_t max_len,
+					     void *result, int *error);
+
+#endif /* _FRR_BGP_FLOWSPEC_UTIL_H */