It reworks the current atomic API: - proposes START/COMMIT/ABORT transaction messages - removes rule flags: rule manipalution is part of a transaction once one has been started - make use of nfnl socket user data: enables transaction per-nfnetlink connection --- include/net/netfilter/nf_tables.h | 9 ++ include/uapi/linux/netfilter/nf_tables.h | 11 +- net/netfilter/nf_tables_api.c | 170 +++++++++++++++++-------------- 3 files changed, 106 insertions(+), 84 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 69cb5ea..490acb0 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -354,6 +354,15 @@ struct nft_rule_update { struct net *net; }; +/** + * struct nft_transaction - nf_tables transaction + * + * @updates: list of rule updates for the current transaction + */ +struct nft_transaction { + struct list_head updates; +}; + static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule) { return (struct nft_expr *)&rule->data[0]; diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 76b215f..8f8d6a6 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -37,8 +37,9 @@ enum nf_tables_msg_types { NFT_MSG_NEWSETELEM, NFT_MSG_GETSETELEM, NFT_MSG_DELSETELEM, - NFT_MSG_COMMIT, - NFT_MSG_ABORT, + NFT_MSG_START_TRANSACTION, + NFT_MSG_COMMIT_TRANSACTION, + NFT_MSG_ABORT_TRANSACTION, NFT_MSG_MAX, }; @@ -88,18 +89,12 @@ enum nft_chain_attributes { }; #define NFTA_CHAIN_MAX (__NFTA_CHAIN_MAX - 1) -enum { - NFT_RULE_F_COMMIT = (1 << 0), - NFT_RULE_F_MASK = NFT_RULE_F_COMMIT, -}; - enum nft_rule_attributes { NFTA_RULE_UNSPEC, NFTA_RULE_TABLE, NFTA_RULE_CHAIN, NFTA_RULE_HANDLE, NFTA_RULE_EXPRESSIONS, - NFTA_RULE_FLAGS, NFTA_RULE_COMPAT, __NFTA_RULE_MAX }; diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index d2da5df..7d2cbd5 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1264,7 +1264,6 @@ static const struct nla_policy nft_rule_policy[NFTA_RULE_MAX + 1] = { .len = NFT_CHAIN_MAXNAMELEN - 1 }, [NFTA_RULE_HANDLE] = { .type = NLA_U64 }, [NFTA_RULE_EXPRESSIONS] = { .type = NLA_NESTED }, - [NFTA_RULE_FLAGS] = { .type = NLA_U32 }, [NFTA_RULE_COMPAT] = { .type = NLA_NESTED }, }; @@ -1518,16 +1517,12 @@ static void nf_tables_rule_destroy(struct nft_rule *rule) static struct nft_expr_info *info; -static int nf_tables_dirty_add(struct nft_rule *rule, const struct nft_ctx *ctx) +static int nf_tables_transaction_add(const struct nft_ctx *ctx, + struct nft_transaction *transaction, + struct nft_rule *rule) { struct nft_rule_update *rupd; - /* Another socket owns the dirty list? */ - if (!ctx->net->nft.pid_owner) - ctx->net->nft.pid_owner = ctx->nlh->nlmsg_pid; - else if (ctx->net->nft.pid_owner != ctx->nlh->nlmsg_pid) - return -EBUSY; - rupd = kmalloc(sizeof(struct nft_rule_update), GFP_KERNEL); if (rupd == NULL) return -ENOMEM; @@ -1536,7 +1531,7 @@ static int nf_tables_dirty_add(struct nft_rule *rule, const struct nft_ctx *ctx) rupd->table = ctx->table; rupd->rule = rule; rupd->net = ctx->net; - list_add(&rupd->list, &ctx->net->nft.dirty_rules); + list_add(&rupd->list, &transaction->updates); return 0; } @@ -1547,6 +1542,7 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, { const struct nfgenmsg *nfmsg = nlmsg_data(nlh); const struct nft_af_info *afi; + struct nft_transaction *transaction = nlsk->sk_user_data; struct net *net = sock_net(skb->sk); struct nft_table *table; struct nft_chain *chain; @@ -1557,7 +1553,6 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, unsigned int size, i, n; int err, rem; bool create; - u32 flags = 0; u64 handle; create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false; @@ -1616,15 +1611,6 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, if (rule == NULL) goto err1; - if (nla[NFTA_RULE_FLAGS]) { - flags = ntohl(nla_get_be32(nla[NFTA_RULE_FLAGS])); - if (flags & ~NFT_RULE_F_MASK) - return -EINVAL; - - if (flags & NFT_RULE_F_COMMIT) - nft_rule_activate_next(net, rule); - } - rule->handle = handle; rule->dlen = size; @@ -1637,8 +1623,11 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, expr = nft_expr_next(expr); } + if (transaction != NULL) + nft_rule_activate_next(net, rule); + if (nlh->nlmsg_flags & NLM_F_REPLACE) { - if (flags & NFT_RULE_F_COMMIT) { + if (transaction != NULL) { nft_rule_disactivate_next(net, old_rule); list_add_tail_rcu(&rule->list, &chain->rules); } else { @@ -1650,8 +1639,8 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, else list_add_rcu(&rule->list, &chain->rules); - if (flags & NFT_RULE_F_COMMIT) { - err = nf_tables_dirty_add(rule, &ctx); + if (transaction != NULL) { + err = nf_tables_transaction_add(&ctx, transaction, rule); if (err < 0) { list_del_rcu(&rule->list); goto err2; @@ -1659,7 +1648,8 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, } else { nf_tables_rule_notify(skb, nlh, table, chain, rule, NFT_MSG_NEWRULE, - nlh->nlmsg_flags & (NLM_F_APPEND | NLM_F_REPLACE), + nlh->nlmsg_flags & + (NLM_F_APPEND | NLM_F_REPLACE), nfmsg->nfgen_family); } return 0; @@ -1674,17 +1664,18 @@ err1: return err; } -static int -nf_tables_delrule_one(struct nft_ctx *ctx, struct nft_rule *rule, u32 flags) +static int nf_tables_delrule_one(struct nft_ctx *ctx, + struct nft_transaction *transaction, + struct nft_rule *rule) { int ret = 0; - if (flags & NFT_RULE_F_COMMIT) { + if (transaction != NULL) { /* Will be deleted already in the next generation */ if (!nft_rule_is_active_next(ctx->net, rule)) return -EBUSY; - ret = nf_tables_dirty_add(rule, ctx); + ret = nf_tables_transaction_add(ctx, transaction, rule); if (ret >= 0) nft_rule_disactivate_next(ctx->net, rule); } else { @@ -1703,13 +1694,13 @@ static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb, { const struct nfgenmsg *nfmsg = nlmsg_data(nlh); const struct nft_af_info *afi; + struct nft_transaction *transaction = nlsk->sk_user_data; struct net *net = sock_net(skb->sk); const struct nft_table *table; struct nft_chain *chain; struct nft_rule *rule, *tmp; int family = nfmsg->nfgen_family, err; struct nft_ctx ctx; - u32 flags = 0; afi = nf_tables_afinfo_lookup(net, family, false); if (IS_ERR(afi)) @@ -1725,44 +1716,59 @@ static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb, nft_ctx_init(&ctx, skb, nlh, afi, table, chain, nla); - if (nla[NFTA_RULE_FLAGS]) { - flags = ntohl(nla_get_be32(nla[NFTA_RULE_FLAGS])); - - if (flags & ~NFT_RULE_F_MASK) - return -EINVAL; - } - if (nla[NFTA_RULE_HANDLE]) { rule = nf_tables_rule_lookup(chain, nla[NFTA_RULE_HANDLE]); if (IS_ERR(rule)) return PTR_ERR(rule); - err = nf_tables_delrule_one(&ctx, rule, flags); + err = nf_tables_delrule_one(&ctx, transaction, rule); if (err < 0) return err; } else { /* Remove all rules in this chain */ list_for_each_entry_safe(rule, tmp, &chain->rules, list) - nf_tables_delrule_one(&ctx, rule, flags); + nf_tables_delrule_one(&ctx, transaction, rule); } return 0; } -static int nf_tables_commit(struct sock *nlsk, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nla[]) +static int nf_tables_start_transaction(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + struct nft_transaction *transaction; + + if (nlsk->sk_user_data != NULL) + return -EALREADY; + + transaction = kmalloc(sizeof(struct nft_transaction), GFP_KERNEL); + if (transaction == NULL) + return -ENOMEM; + + INIT_LIST_HEAD(&transaction->updates); + nlsk->sk_user_data = transaction; + + return 0; +} + +static int nf_tables_commit_transaction(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) { const struct nfgenmsg *nfmsg = nlmsg_data(nlh); const struct nft_af_info *afi; + struct nft_transaction *transaction = nlsk->sk_user_data; struct net *net = sock_net(skb->sk); struct nft_rule_update *rupd, *tmp; int family = nfmsg->nfgen_family; bool create; - /* Are you the owner of the dirty list? */ - if (nlh->nlmsg_pid != net->nft.pid_owner) - return -EBUSY; + if (transaction == NULL) + return -EINVAL; + + if (list_empty(&transaction->updates)) + goto done; create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false; @@ -1781,7 +1787,7 @@ static int nf_tables_commit(struct sock *nlsk, struct sk_buff *skb, */ synchronize_rcu(); - list_for_each_entry_safe(rupd, tmp, &net->nft.dirty_rules, list) { + list_for_each_entry_safe(rupd, tmp, &transaction->updates, list) { /* Delete this rule from the dirty list */ list_del(&rupd->list); @@ -1806,47 +1812,47 @@ static int nf_tables_commit(struct sock *nlsk, struct sk_buff *skb, nf_tables_rule_destroy(rupd->rule); kfree(rupd); } - /* Clear owner of this dirty list */ - net->nft.pid_owner = 0; + +done: + kfree(transaction); + nlsk->sk_user_data = NULL; return 0; } -static void nf_tables_abort_all(struct net *net) +static void nf_tables_abort_all(struct nft_transaction *transaction) { struct nft_rule_update *rupd, *tmp; - list_for_each_entry_safe(rupd, tmp, &net->nft.dirty_rules, list) { - /* Delete all rules from the dirty list */ + list_for_each_entry_safe(rupd, tmp, &transaction->updates, list) { + /* Delete all rules from the update list */ list_del(&rupd->list); - if (!nft_rule_is_active_next(rupd->net, rupd->rule)) { + if (nft_rule_is_active_next(rupd->net, rupd->rule)) { + list_del_rcu(&rupd->rule->list); + nf_tables_rule_destroy(rupd->rule); + } else nft_rule_clear(rupd->net, rupd->rule); - kfree(rupd); - return; - } - /* This rule is inactive, get rid of it */ - list_del_rcu(&rupd->rule->list); - nf_tables_rule_destroy(rupd->rule); kfree(rupd); } - /* Clear the owner of the dirty list */ - net->nft.pid_owner = 0; } -static int nf_tables_abort(struct sock *nlsk, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nla[]) +static int nf_tables_abort_transaction(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) { const struct nfgenmsg *nfmsg = nlmsg_data(nlh); const struct nft_af_info *afi; + struct nft_transaction *transaction = nlsk->sk_user_data; struct net *net = sock_net(skb->sk); bool create; - /* Are you the owner of the dirty list? */ - if (nlh->nlmsg_pid != net->nft.pid_owner) - return -EBUSY; + if (transaction == NULL) + return -EINVAL; + + if (list_empty(&transaction->updates)) + goto done; create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false; @@ -1854,24 +1860,31 @@ static int nf_tables_abort(struct sock *nlsk, struct sk_buff *skb, if (IS_ERR(afi)) return PTR_ERR(afi); - nf_tables_abort_all(net); + nf_tables_abort_all(transaction); + +done: + kfree(transaction); + nlsk->sk_user_data = NULL; return 0; } -static int -nf_tables_rcv_nl_event(struct notifier_block *this, - unsigned long event, void *ptr) +static int nf_tables_rcv_nl_event(struct notifier_block *this, + unsigned long event, void *ptr) { struct netlink_notify *n = ptr; + struct nft_transaction *transaction; if (event != NETLINK_URELEASE || n->protocol != NETLINK_NETFILTER) return NOTIFY_DONE; - if (n->portid != n->net->nft.pid_owner) - return NOTIFY_DONE; - - nf_tables_abort_all(n->net); + transaction = n->net->nfnl->sk_user_data; + if (transaction != NULL) { + if (!list_empty(&transaction->updates)) + nf_tables_abort_all(transaction); + kfree(transaction); + n->net->nfnl->sk_user_data = NULL; + } return NOTIFY_DONE; } @@ -2840,13 +2853,18 @@ static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = { .attr_count = NFTA_SET_ELEM_LIST_MAX, .policy = nft_set_elem_list_policy, }, - [NFT_MSG_COMMIT] = { - .call = nf_tables_commit, + [NFT_MSG_START_TRANSACTION] = { + .call = nf_tables_start_transaction, + .attr_count = NFTA_TABLE_MAX, + .policy = nft_rule_policy, + }, + [NFT_MSG_COMMIT_TRANSACTION] = { + .call = nf_tables_commit_transaction, .attr_count = NFTA_TABLE_MAX, .policy = nft_rule_policy, }, - [NFT_MSG_ABORT] = { - .call = nf_tables_abort, + [NFT_MSG_ABORT_TRANSACTION] = { + .call = nf_tables_abort_transaction, .attr_count = NFTA_TABLE_MAX, .policy = nft_rule_policy, }, -- 1.8.1.5 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html