diff options
| -rw-r--r-- | include/net/genetlink.h | 5 | ||||
| -rw-r--r-- | net/netlink/genetlink.c | 59 |
2 files changed, 64 insertions, 0 deletions
diff --git a/include/net/genetlink.h b/include/net/genetlink.h index 38620da4aa7a..3ed31e5a445b 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -31,6 +31,9 @@ struct genl_info; * do additional, common, filtering and return an error * @post_doit: called after an operation's doit callback, it may * undo operations done by pre_doit, for example release locks + * @mcast_bind: a socket bound to the given multicast group (which + * is given as the offset into the groups array) + * @mcast_unbind: a socket was unbound from the given multicast group * @attrbuf: buffer to store parsed attributes * @family_list: family list * @mcgrps: multicast groups used by this family (private) @@ -53,6 +56,8 @@ struct genl_family { void (*post_doit)(const struct genl_ops *ops, struct sk_buff *skb, struct genl_info *info); + int (*mcast_bind)(int group); + void (*mcast_unbind)(int group); struct nlattr ** attrbuf; /* private */ const struct genl_ops * ops; /* private */ const struct genl_multicast_group *mcgrps; /* private */ diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 76393f2f4b22..05bf40bbd189 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -983,11 +983,70 @@ static struct genl_multicast_group genl_ctrl_groups[] = { { .name = "notify", }, }; +static int genl_bind(int group) +{ + int i, err; + bool found = false; + + down_read(&cb_lock); + for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { + struct genl_family *f; + + list_for_each_entry(f, genl_family_chain(i), family_list) { + if (group >= f->mcgrp_offset && + group < f->mcgrp_offset + f->n_mcgrps) { + int fam_grp = group - f->mcgrp_offset; + + if (f->mcast_bind) + err = f->mcast_bind(fam_grp); + else + err = 0; + found = true; + break; + } + } + } + up_read(&cb_lock); + + if (WARN_ON(!found)) + err = 0; + + return err; +} + +static void genl_unbind(int group) +{ + int i; + bool found = false; + + down_read(&cb_lock); + for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { + struct genl_family *f; + + list_for_each_entry(f, genl_family_chain(i), family_list) { + if (group >= f->mcgrp_offset && + group < f->mcgrp_offset + f->n_mcgrps) { + int fam_grp = group - f->mcgrp_offset; + + if (f->mcast_unbind) + f->mcast_unbind(fam_grp); + found = true; + break; + } + } + } + up_read(&cb_lock); + + WARN_ON(!found); +} + static int __net_init genl_pernet_init(struct net *net) { struct netlink_kernel_cfg cfg = { .input = genl_rcv, .flags = NL_CFG_F_NONROOT_RECV, + .bind = genl_bind, + .unbind = genl_unbind, }; /* we'll bump the group number right afterwards */ |