... IEEE 802.1ad (802.1QinQ) specifies architecture and bridge protocols to provide separate instances of the MAC services to multiple independent users of a Bridged Local Area Network in a manner that does not require cooperation among the users, and requires a minimum of cooperation between the users and the provider of the MAC service.
The idea is to provide, for example, the possibility for customers to run their own VLANs inside service provider's provided VLAN. This way the service provider can just configure one VLAN for the customer and customer can then treat that VLAN as if it was a trunk. ... http://en.wikipedia.org/wiki/802.1ad "Customer" VLAN - ether_type: 0x8100 Stored in: struct pkthdr { ... union { u_int16_t vt_vtag; /* Ethernet 802.1p+q vlan tag */ u_int16_t vt_nrecs; /* # of IGMPv3 records in this chain */ } PH_vt; SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */ }; #define ether_vtag PH_vt.vt_vtag "Service Provider" VLAN - ether_type: 0x88a8/0x8100/0x9100 How I can store it in packet? How to store tag for QinQinQ? VLAN tags store implementation (IMHO) Ethernet packet: | Dst_MAC | Src_MAC | 802.1Q_Tag2 | 802.1Q_Tag1 | 802.1Q_Tag0 | Ether_type/size | Payload | 802.1Q Tag0 = "Customer" VLAN - ether_type: 0x8100, stored in pkthdr.PH_vt.vt_vtag (now) (IEEE 802.1Q) 802.1Q Tag1 = "Service Provider" / MetroTag... (IEEE 802.1ad) 802.1Q Tag2 = SomeTag... (QinQinQ) I found part of old code in /usr/src/sys/dev/mxge/if_mxge.c: ... /* save the tag */ #ifdef MXGE_NEW_VLAN_API m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); #else { struct m_tag *mtag; mtag = m_tag_alloc(MTAG_VLAN, MTAG_VLAN_TAG, sizeof(u_int), M_NOWAIT); if (mtag == NULL) return; VLAN_TAG_VALUE(mtag) = ntohs(evl->evl_tag); m_tag_prepend(m, mtag); } #endif m->m_flags |= M_VLANTAG; ... 1. Compact scheme: #define MTAG_VLAN_T0 1035328035 /* m_tag_cookie */ #define MTAG_VLAN_T1 (MTAG_VLAN_T0 + 1) #define MTAG_VLAN_T2 (MTAG_VLAN_T1 + 1) #define MTAG_VLAN_T3 (MTAG_VLAN_T2 + 1) Store vt_vtag in m_tag_id ng_vlan / if_vlan will use for tag/untag one of MTAG_VLAN_Tx m_tag_cookie and tunable ether_type for vlan encapsulation: lower <-> ng_vlan(MTAG_VLAN_T0) <-> ng_vlan(MTAG_VLAN_T1) <-> ng_vlan(MTAG_VLAN_T2) <-> upper 2. OpenBSD compatible #ifdef <OPENBSD> #define MTAG_VLAN MTAG_ABI_COMPAT /* cookie */ #define MTAG_VLAN_TAG0 1035328035 #else #define MTAG_VLAN 1035328035 /* m_tag_cookie */ #define MTAG_VLAN_TAG0 0 /* tag of VLAN interface */ #endif #define MTAG_VLAN_TAG1 (MTAG_VLAN_TAG0 + 1) #define MTAG_VLAN_TAG2 (MTAG_VLAN_TAG1 + 1) #define MTAG_VLAN_TAG3 (MTAG_VLAN_TAG2 + 1) struct mv_tag { struct m_tag tag; u_int16_t vt_vtag; /* Ethernet 802.1p+q vlan tag */ }; ng_vlan / if_vlan will use for tag/untag one of MTAG_VLAN_TAGx m_tag_id and tunable ether_type for vlan encapsulation: lower <-> ng_vlan(MTAG_VLAN_TAG0) <-> ng_vlan(MTAG_VLAN_TAG1) <-> ng_vlan(MTAG_VLAN_TAG2) <-> upper 3. Extended Same as 2, but struct mv_tag { struct m_tag tag; u_int16_t vt_vtag; /* Ethernet 802.1p+q vlan tag */ u_int16_t ether_type; /* Ethernet type for TAG */ }; Major question is: were store 802.1Q Tag0 = "Customer" VLAN (ether_type: 0x8100, IEEE 802.1Q): in pkthdr.PH_vt.vt_vtag or in struct m_tag? ng_vlan modifications (I can make): + tunable ether_type for vlan encapsulation + tunable on/off encapsulation (to prevent network adapter encapsulation) + tunable m_tag identifier for VLAN tag ...??? Any comments before I start? PS: Trick: kern.ipc.max_linkhdr should be increased via sysctl: 20 - 1 VLAN tag (.Q) 24 - 2 VLAN tags (QinQ) 28 - 3 VLAN tags (QinQinQ) 32 - 4 VLAN tags (...) -- Rozhuk Ivan _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
