From ae243bee397102c51fbf9db440eca3b077e0e702 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 7 Jun 2012 14:19:42 +0200 Subject: netfilter: ctnetlink: add CTA_HELP_INFO attribute This attribute can be used to modify and to dump the internal protocol information. Signed-off-by: Pablo Neira Ayuso diff --git a/include/linux/netfilter/nfnetlink_conntrack.h b/include/linux/netfilter/nfnetlink_conntrack.h index e58e4b9..7688833 100644 --- a/include/linux/netfilter/nfnetlink_conntrack.h +++ b/include/linux/netfilter/nfnetlink_conntrack.h @@ -191,6 +191,7 @@ enum ctattr_expect_nat { enum ctattr_help { CTA_HELP_UNSPEC, CTA_HELP_NAME, + CTA_HELP_INFO, __CTA_HELP_MAX }; #define CTA_HELP_MAX (__CTA_HELP_MAX - 1) diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h index 061352f..84b24c3 100644 --- a/include/net/netfilter/nf_conntrack_helper.h +++ b/include/net/netfilter/nf_conntrack_helper.h @@ -39,6 +39,7 @@ struct nf_conntrack_helper { void (*destroy)(struct nf_conn *ct); + int (*from_nlattr)(struct nlattr *attr, struct nf_conn *ct); int (*to_nlattr)(struct sk_buff *skb, const struct nf_conn *ct); unsigned int expect_class_max; }; diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 8be0ab9..ae156df 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -902,7 +902,8 @@ static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = { }; static inline int -ctnetlink_parse_help(const struct nlattr *attr, char **helper_name) +ctnetlink_parse_help(const struct nlattr *attr, char **helper_name, + struct nlattr **helpinfo) { struct nlattr *tb[CTA_HELP_MAX+1]; @@ -913,6 +914,9 @@ ctnetlink_parse_help(const struct nlattr *attr, char **helper_name) *helper_name = nla_data(tb[CTA_HELP_NAME]); + if (tb[CTA_HELP_INFO]) + *helpinfo = tb[CTA_HELP_INFO]; + return 0; } @@ -1173,13 +1177,14 @@ ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[]) struct nf_conntrack_helper *helper; struct nf_conn_help *help = nfct_help(ct); char *helpname = NULL; + struct nlattr *helpinfo = NULL; int err; /* don't change helper of sibling connections */ if (ct->master) return -EBUSY; - err = ctnetlink_parse_help(cda[CTA_HELP], &helpname); + err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo); if (err < 0) return err; @@ -1214,8 +1219,12 @@ ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[]) } if (help) { - if (help->helper == helper) + if (help->helper == helper) { + /* update private helper data if allowed. */ + if (helper->from_nlattr && helpinfo) + helper->from_nlattr(helpinfo, ct); return 0; + } if (help->helper) return -EBUSY; /* need to zero data of old helper */ @@ -1411,8 +1420,9 @@ ctnetlink_create_conntrack(struct net *net, u16 zone, rcu_read_lock(); if (cda[CTA_HELP]) { char *helpname = NULL; - - err = ctnetlink_parse_help(cda[CTA_HELP], &helpname); + struct nlattr *helpinfo = NULL; + + err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo); if (err < 0) goto err2; @@ -1446,6 +1456,9 @@ ctnetlink_create_conntrack(struct net *net, u16 zone, err = -ENOMEM; goto err2; } + /* set private helper data if allowed. */ + if (helper->from_nlattr && helpinfo) + helper->from_nlattr(helpinfo, ct); /* not in hash table yet so not strictly necessary */ RCU_INIT_POINTER(help->helper, helper); -- cgit v0.10.2