From 556d299fcb4af8f2e8eacf311c4eee352c746788 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 31 Oct 2016 13:21:02 +0100 Subject: [PATCH 1/4] net: pim: add common pimhdr struct and helpers Add the common pimhdr structure and helpers to access it, also cleanup the format of the header file. Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- include/linux/pim.h | 44 ++++++++++++++++++++++++++++++++++++-------- 1 file changed, 36 insertions(+), 8 deletions(-) diff --git a/include/linux/pim.h b/include/linux/pim.h index e1d756f81348..354235a2691b 100644 --- a/include/linux/pim.h +++ b/include/linux/pim.h @@ -1,6 +1,7 @@ #ifndef __LINUX_PIM_H #define __LINUX_PIM_H +#include #include /* Message types - V1 */ @@ -13,20 +14,47 @@ #define PIM_NULL_REGISTER cpu_to_be32(0x40000000) -static inline bool ipmr_pimsm_enabled(void) -{ - return IS_BUILTIN(CONFIG_IP_PIMSM_V1) || IS_BUILTIN(CONFIG_IP_PIMSM_V2); -} +/* RFC7761, sec 4.9: + * The PIM header common to all PIM messages is: + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |PIM Ver| Type | Reserved | Checksum | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ +struct pimhdr { + __u8 type; + __u8 reserved; + __be16 csum; +}; /* PIMv2 register message header layout (ietf-draft-idmr-pimvsm-v2-00.ps */ -struct pimreghdr -{ +struct pimreghdr { __u8 type; __u8 reserved; __be16 csum; __be32 flags; }; -struct sk_buff; -extern int pim_rcv_v1(struct sk_buff *); +int pim_rcv_v1(struct sk_buff *skb); + +static inline bool ipmr_pimsm_enabled(void) +{ + return IS_BUILTIN(CONFIG_IP_PIMSM_V1) || IS_BUILTIN(CONFIG_IP_PIMSM_V2); +} + +static inline struct pimhdr *pim_hdr(const struct sk_buff *skb) +{ + return (struct pimhdr *)skb_transport_header(skb); +} + +static inline u8 pim_hdr_version(const struct pimhdr *pimhdr) +{ + return pimhdr->type >> 4; +} + +static inline u8 pim_hdr_type(const struct pimhdr *pimhdr) +{ + return pimhdr->type & 0xf; +} #endif From 20bb6ce9879e19eee7539329eaa2408d12b00306 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 31 Oct 2016 13:21:03 +0100 Subject: [PATCH 2/4] net: pim: add a helper to check for IPv4 all pim routers address Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- include/linux/pim.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/pim.h b/include/linux/pim.h index 354235a2691b..1b6c0dbba94e 100644 --- a/include/linux/pim.h +++ b/include/linux/pim.h @@ -57,4 +57,10 @@ static inline u8 pim_hdr_type(const struct pimhdr *pimhdr) { return pimhdr->type & 0xf; } + +/* check if the address is 224.0.0.13, RFC7761 sec 4.3.1 */ +static inline bool pim_ipv4_all_pim_routers(__be32 addr) +{ + return addr == htonl(0xE000000D); +} #endif From 56245cae19f5ccb371fa63b09bb6b9ce7c0f1266 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 31 Oct 2016 13:21:04 +0100 Subject: [PATCH 3/4] net: pim: add all RFC7761 message types Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- include/linux/pim.h | 31 ++++++++++++++++++++++++++++++- net/ipv4/ipmr.c | 2 +- net/ipv6/ip6mr.c | 2 +- 3 files changed, 32 insertions(+), 3 deletions(-) diff --git a/include/linux/pim.h b/include/linux/pim.h index 1b6c0dbba94e..0e81b2778ae0 100644 --- a/include/linux/pim.h +++ b/include/linux/pim.h @@ -10,7 +10,36 @@ /* Message types - V2 */ #define PIM_VERSION 2 -#define PIM_REGISTER 1 + +/* RFC7761, sec 4.9: + * Type + * Types for specific PIM messages. PIM Types are: + * + * Message Type Destination + * --------------------------------------------------------------------- + * 0 = Hello Multicast to ALL-PIM-ROUTERS + * 1 = Register Unicast to RP + * 2 = Register-Stop Unicast to source of Register + * packet + * 3 = Join/Prune Multicast to ALL-PIM-ROUTERS + * 4 = Bootstrap Multicast to ALL-PIM-ROUTERS + * 5 = Assert Multicast to ALL-PIM-ROUTERS + * 6 = Graft (used in PIM-DM only) Unicast to RPF'(S) + * 7 = Graft-Ack (used in PIM-DM only) Unicast to source of Graft + * packet + * 8 = Candidate-RP-Advertisement Unicast to Domain's BSR + */ +enum { + PIM_TYPE_HELLO, + PIM_TYPE_REGISTER, + PIM_TYPE_REGISTER_STOP, + PIM_TYPE_JOIN_PRUNE, + PIM_TYPE_BOOTSTRAP, + PIM_TYPE_ASSERT, + PIM_TYPE_GRAFT, + PIM_TYPE_GRAFT_ACK, + PIM_TYPE_CANDIDATE_RP_ADV +}; #define PIM_NULL_REGISTER cpu_to_be32(0x40000000) diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 5f006e13de56..51d71a70fbbe 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -2053,7 +2053,7 @@ static int pim_rcv(struct sk_buff *skb) goto drop; pim = (struct pimreghdr *)skb_transport_header(skb); - if (pim->type != ((PIM_VERSION << 4) | (PIM_REGISTER)) || + if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) || (pim->flags & PIM_NULL_REGISTER) || (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && csum_fold(skb_checksum(skb, 0, skb->len, 0)))) diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index 7f4265b1649b..52101b37ad6e 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -636,7 +636,7 @@ static int pim6_rcv(struct sk_buff *skb) goto drop; pim = (struct pimreghdr *)skb_transport_header(skb); - if (pim->type != ((PIM_VERSION << 4) | PIM_REGISTER) || + if (pim->type != ((PIM_VERSION << 4) | PIM_TYPE_REGISTER) || (pim->flags & PIM_NULL_REGISTER) || (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, sizeof(*pim), IPPROTO_PIM, From 91b02d3d133bbb101466325cdd9a6007cd9ec5a8 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 31 Oct 2016 13:21:05 +0100 Subject: [PATCH 4/4] bridge: mcast: add router port on PIM hello message When we receive a PIM Hello message on a port we can consider that it has a multicast router attached, thus it is correct to add it to the router list. The only catch is it shouldn't be considered for a querier. Using Daniel's description: leaf-11 leaf-12 leaf-13 \ | / bridge-1 / \ host-11 host-12 - all ports in bridge-1 are in a single vlan aware bridge - leaf-11 is the IGMP querier - leaf-13 is the PIM DR - host-11 TXes packets to 226.10.10.10 - bridge-1 only forwards the 226.10.10.10 traffic out the port to leaf-11, it should also forward this traffic out the port to leaf-13 Suggested-by: Daniel Walton Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 2136e45f5277..073d54afa056 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #if IS_ENABLED(CONFIG_IPV6) #include @@ -1638,6 +1639,21 @@ static void br_multicast_err_count(const struct net_bridge *br, u64_stats_update_end(&pstats->syncp); } +static void br_multicast_pim(struct net_bridge *br, + struct net_bridge_port *port, + const struct sk_buff *skb) +{ + unsigned int offset = skb_transport_offset(skb); + struct pimhdr *pimhdr, _pimhdr; + + pimhdr = skb_header_pointer(skb, offset, sizeof(_pimhdr), &_pimhdr); + if (!pimhdr || pim_hdr_version(pimhdr) != PIM_VERSION || + pim_hdr_type(pimhdr) != PIM_TYPE_HELLO) + return; + + br_multicast_mark_router(br, port); +} + static int br_multicast_ipv4_rcv(struct net_bridge *br, struct net_bridge_port *port, struct sk_buff *skb, @@ -1650,8 +1666,12 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br, err = ip_mc_check_igmp(skb, &skb_trimmed); if (err == -ENOMSG) { - if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr)) + if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr)) { BR_INPUT_SKB_CB(skb)->mrouters_only = 1; + } else if (pim_ipv4_all_pim_routers(ip_hdr(skb)->daddr)) { + if (ip_hdr(skb)->protocol == IPPROTO_PIM) + br_multicast_pim(br, port, skb); + } return 0; } else if (err < 0) { br_multicast_err_count(br, port, skb->protocol);