From 6afaae6d12f54accf194e73ece617d1f456e438d Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Sat, 10 Dec 2022 16:56:29 +0200 Subject: [PATCH] bridge: mcast: Allow user space to add (*, G) with a source list and filter mode Add new netlink attributes to the RTM_NEWMDB request that allow user space to add (*, G) with a source list and filter mode. The RTM_NEWMDB message can already dump such entries (created by the kernel) so there is no need to add dump support. However, the message contains a different set of attributes depending if it is a request or a response. The naming and structure of the new attributes try to follow the existing ones used in the response. Request: [ struct nlmsghdr ] [ struct br_port_msg ] [ MDBA_SET_ENTRY ] struct br_mdb_entry [ MDBA_SET_ENTRY_ATTRS ] [ MDBE_ATTR_SOURCE ] struct in_addr / struct in6_addr [ MDBE_ATTR_SRC_LIST ] // new [ MDBE_SRC_LIST_ENTRY ] [ MDBE_SRCATTR_ADDRESS ] struct in_addr / struct in6_addr [ ...] [ MDBE_ATTR_GROUP_MODE ] // new u8 Response: [ struct nlmsghdr ] [ struct br_port_msg ] [ MDBA_MDB ] [ MDBA_MDB_ENTRY ] [ MDBA_MDB_ENTRY_INFO ] struct br_mdb_entry [ MDBA_MDB_EATTR_TIMER ] u32 [ MDBA_MDB_EATTR_SOURCE ] struct in_addr / struct in6_addr [ MDBA_MDB_EATTR_RTPROT ] u8 [ MDBA_MDB_EATTR_SRC_LIST ] [ MDBA_MDB_SRCLIST_ENTRY ] [ MDBA_MDB_SRCATTR_ADDRESS ] struct in_addr / struct in6_addr [ MDBA_MDB_SRCATTR_TIMER ] u8 [...] [ MDBA_MDB_EATTR_GROUP_MODE ] u8 Signed-off-by: Ido Schimmel Acked-by: Nikolay Aleksandrov Signed-off-by: Jakub Kicinski --- include/uapi/linux/if_bridge.h | 20 +++++ net/bridge/br_mdb.c | 130 +++++++++++++++++++++++++++++++++ 2 files changed, 150 insertions(+) diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h index a86a7e7b811f..0d9fe73fc48c 100644 --- a/include/uapi/linux/if_bridge.h +++ b/include/uapi/linux/if_bridge.h @@ -723,10 +723,30 @@ enum { enum { MDBE_ATTR_UNSPEC, MDBE_ATTR_SOURCE, + MDBE_ATTR_SRC_LIST, + MDBE_ATTR_GROUP_MODE, __MDBE_ATTR_MAX, }; #define MDBE_ATTR_MAX (__MDBE_ATTR_MAX - 1) +/* per mdb entry source */ +enum { + MDBE_SRC_LIST_UNSPEC, + MDBE_SRC_LIST_ENTRY, + __MDBE_SRC_LIST_MAX, +}; +#define MDBE_SRC_LIST_MAX (__MDBE_SRC_LIST_MAX - 1) + +/* per mdb entry per source attributes + * these are embedded in MDBE_SRC_LIST_ENTRY + */ +enum { + MDBE_SRCATTR_UNSPEC, + MDBE_SRCATTR_ADDRESS, + __MDBE_SRCATTR_MAX, +}; +#define MDBE_SRCATTR_MAX (__MDBE_SRCATTR_MAX - 1) + /* Embedded inside LINK_XSTATS_TYPE_BRIDGE */ enum { BRIDGE_XSTATS_UNSPEC, diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c index e9a4b7e247e7..61d46b0a31b6 100644 --- a/net/bridge/br_mdb.c +++ b/net/bridge/br_mdb.c @@ -663,10 +663,25 @@ errout: rtnl_set_sk_err(net, RTNLGRP_MDB, err); } +static const struct nla_policy +br_mdbe_src_list_entry_pol[MDBE_SRCATTR_MAX + 1] = { + [MDBE_SRCATTR_ADDRESS] = NLA_POLICY_RANGE(NLA_BINARY, + sizeof(struct in_addr), + sizeof(struct in6_addr)), +}; + +static const struct nla_policy +br_mdbe_src_list_pol[MDBE_SRC_LIST_MAX + 1] = { + [MDBE_SRC_LIST_ENTRY] = NLA_POLICY_NESTED(br_mdbe_src_list_entry_pol), +}; + static const struct nla_policy br_mdbe_attrs_pol[MDBE_ATTR_MAX + 1] = { [MDBE_ATTR_SOURCE] = NLA_POLICY_RANGE(NLA_BINARY, sizeof(struct in_addr), sizeof(struct in6_addr)), + [MDBE_ATTR_GROUP_MODE] = NLA_POLICY_RANGE(NLA_U8, MCAST_EXCLUDE, + MCAST_INCLUDE), + [MDBE_ATTR_SRC_LIST] = NLA_POLICY_NESTED(br_mdbe_src_list_pol), }; static bool is_valid_mdb_entry(struct br_mdb_entry *entry, @@ -1051,6 +1066,76 @@ static int __br_mdb_add(const struct br_mdb_config *cfg, return ret; } +static int br_mdb_config_src_entry_init(struct nlattr *src_entry, + struct br_mdb_src_entry *src, + __be16 proto, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[MDBE_SRCATTR_MAX + 1]; + int err; + + err = nla_parse_nested(tb, MDBE_SRCATTR_MAX, src_entry, + br_mdbe_src_list_entry_pol, extack); + if (err) + return err; + + if (NL_REQ_ATTR_CHECK(extack, src_entry, tb, MDBE_SRCATTR_ADDRESS)) + return -EINVAL; + + if (!is_valid_mdb_source(tb[MDBE_SRCATTR_ADDRESS], proto, extack)) + return -EINVAL; + + src->addr.proto = proto; + nla_memcpy(&src->addr.src, tb[MDBE_SRCATTR_ADDRESS], + nla_len(tb[MDBE_SRCATTR_ADDRESS])); + + return 0; +} + +static int br_mdb_config_src_list_init(struct nlattr *src_list, + struct br_mdb_config *cfg, + struct netlink_ext_ack *extack) +{ + struct nlattr *src_entry; + int rem, err; + int i = 0; + + nla_for_each_nested(src_entry, src_list, rem) + cfg->num_src_entries++; + + if (cfg->num_src_entries >= PG_SRC_ENT_LIMIT) { + NL_SET_ERR_MSG_FMT_MOD(extack, "Exceeded maximum number of source entries (%u)", + PG_SRC_ENT_LIMIT - 1); + return -EINVAL; + } + + cfg->src_entries = kcalloc(cfg->num_src_entries, + sizeof(struct br_mdb_src_entry), GFP_KERNEL); + if (!cfg->src_entries) + return -ENOMEM; + + nla_for_each_nested(src_entry, src_list, rem) { + err = br_mdb_config_src_entry_init(src_entry, + &cfg->src_entries[i], + cfg->entry->addr.proto, + extack); + if (err) + goto err_src_entry_init; + i++; + } + + return 0; + +err_src_entry_init: + kfree(cfg->src_entries); + return err; +} + +static void br_mdb_config_src_list_fini(struct br_mdb_config *cfg) +{ + kfree(cfg->src_entries); +} + static int br_mdb_config_attrs_init(struct nlattr *set_attrs, struct br_mdb_config *cfg, struct netlink_ext_ack *extack) @@ -1070,6 +1155,44 @@ static int br_mdb_config_attrs_init(struct nlattr *set_attrs, __mdb_entry_to_br_ip(cfg->entry, &cfg->group, mdb_attrs); + if (mdb_attrs[MDBE_ATTR_GROUP_MODE]) { + if (!cfg->p) { + NL_SET_ERR_MSG_MOD(extack, "Filter mode cannot be set for host groups"); + return -EINVAL; + } + if (!br_multicast_is_star_g(&cfg->group)) { + NL_SET_ERR_MSG_MOD(extack, "Filter mode can only be set for (*, G) entries"); + return -EINVAL; + } + cfg->filter_mode = nla_get_u8(mdb_attrs[MDBE_ATTR_GROUP_MODE]); + } else { + cfg->filter_mode = MCAST_EXCLUDE; + } + + if (mdb_attrs[MDBE_ATTR_SRC_LIST]) { + if (!cfg->p) { + NL_SET_ERR_MSG_MOD(extack, "Source list cannot be set for host groups"); + return -EINVAL; + } + if (!br_multicast_is_star_g(&cfg->group)) { + NL_SET_ERR_MSG_MOD(extack, "Source list can only be set for (*, G) entries"); + return -EINVAL; + } + if (!mdb_attrs[MDBE_ATTR_GROUP_MODE]) { + NL_SET_ERR_MSG_MOD(extack, "Source list cannot be set without filter mode"); + return -EINVAL; + } + err = br_mdb_config_src_list_init(mdb_attrs[MDBE_ATTR_SRC_LIST], + cfg, extack); + if (err) + return err; + } + + if (!cfg->num_src_entries && cfg->filter_mode == MCAST_INCLUDE) { + NL_SET_ERR_MSG_MOD(extack, "Cannot add (*, G) INCLUDE with an empty source list"); + return -EINVAL; + } + return 0; } @@ -1162,6 +1285,11 @@ static int br_mdb_config_init(struct net *net, const struct nlmsghdr *nlh, return 0; } +static void br_mdb_config_fini(struct br_mdb_config *cfg) +{ + br_mdb_config_src_list_fini(cfg); +} + static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { @@ -1220,6 +1348,7 @@ static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, } out: + br_mdb_config_fini(&cfg); return err; } @@ -1295,6 +1424,7 @@ static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, err = __br_mdb_del(&cfg); } + br_mdb_config_fini(&cfg); return err; }