From 46126db9c86110e5fc1e369b9bb89735ddefdae4 Mon Sep 17 00:00:00 2001 From: Wojciech Drewek Date: Mon, 18 Jul 2022 14:18:10 +0200 Subject: flow_dissector: Add PPPoE dissectors Allow to dissect PPPoE specific fields which are: - session ID (16 bits) - ppp protocol (16 bits) - type (16 bits) - this is PPPoE ethertype, for now only ETH_P_PPP_SES is supported, possible ETH_P_PPP_DISC in the future The goal is to make the following TC command possible: # tc filter add dev ens6f0 ingress prio 1 protocol ppp_ses \ flower \ pppoe_sid 12 \ ppp_proto ip \ action drop Note that only PPPoE Session is supported. Signed-off-by: Wojciech Drewek Acked-by: Guillaume Nault Signed-off-by: Tony Nguyen --- include/linux/ppp_defs.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ppp_defs.h b/include/linux/ppp_defs.h index 9d2b388fae1a..b7e57fdbd413 100644 --- a/include/linux/ppp_defs.h +++ b/include/linux/ppp_defs.h @@ -11,4 +11,18 @@ #include #define PPP_FCS(fcs, c) crc_ccitt_byte(fcs, c) + +/** + * ppp_proto_is_valid - checks if PPP protocol is valid + * @proto: PPP protocol + * + * Assumes proto is not compressed. + * Protocol is valid if the value is odd and the least significant bit of the + * most significant octet is 0 (see RFC 1661, section 2). + */ +static inline bool ppp_proto_is_valid(u16 proto) +{ + return !!((proto & 0x0101) == 0x0001); +} + #endif /* _PPP_DEFS_H_ */ -- cgit v1.2.3