diff options
Diffstat (limited to 'net/netfilter/nf_tables_api.c')
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 1078 |
1 files changed, 1070 insertions, 8 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 7d59c89..5092c81 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net> + * Copyright (c) 2007-2009 Patrick McHardy <kaber@trash.net> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -315,6 +315,7 @@ static int nf_tables_newtable(struct sock *nlsk, struct sk_buff *skb, nla_strlcpy(table->name, name, nla_len(name)); INIT_LIST_HEAD(&table->chains); + INIT_LIST_HEAD(&table->sets); list_add_tail(&table->list, &afi->tables); nf_tables_table_notify(skb, nlh, table, NFT_MSG_NEWTABLE, family); @@ -409,6 +410,7 @@ again: } table->flags |= NFT_TABLE_BUILTIN; + INIT_LIST_HEAD(&table->sets); list_add_tail(&table->list, &afi->tables); nf_tables_table_notify(NULL, NULL, table, NFT_MSG_NEWTABLE, family); list_for_each_entry(chain, &table->chains, list) @@ -820,10 +822,14 @@ static int nf_tables_delchain(struct sock *nlsk, struct sk_buff *skb, } static void nft_ctx_init(struct nft_ctx *ctx, + const struct sk_buff *skb, + const struct nlmsghdr *nlh, const struct nft_af_info *afi, const struct nft_table *table, const struct nft_chain *chain) { + ctx->skb = skb; + ctx->nlh = nlh; ctx->afi = afi; ctx->table = table; ctx->chain = chain; @@ -1301,7 +1307,7 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, rule->handle = handle; rule->dlen = size; - nft_ctx_init(&ctx, afi, table, chain); + nft_ctx_init(&ctx, skb, nlh, afi, table, chain); expr = nft_expr_first(rule); for (i = 0; i < n; i++) { err = nf_tables_newexpr(&ctx, &info[i], expr); @@ -1392,6 +1398,939 @@ static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb, return 0; } +/* + * Sets + */ + +static LIST_HEAD(nf_tables_set_ops); + +int nft_register_set(struct nft_set_ops *ops) +{ + nfnl_lock(NFNL_SUBSYS_NFTABLES); + list_add_tail(&ops->list, &nf_tables_set_ops); + nfnl_unlock(NFNL_SUBSYS_NFTABLES); + return 0; +} +EXPORT_SYMBOL_GPL(nft_register_set); + +void nft_unregister_set(struct nft_set_ops *ops) +{ + nfnl_lock(NFNL_SUBSYS_NFTABLES); + list_del(&ops->list); + nfnl_unlock(NFNL_SUBSYS_NFTABLES); +} +EXPORT_SYMBOL_GPL(nft_unregister_set); + +static const struct nft_set_ops *nft_select_set_ops(const struct nlattr * const nla[]) +{ + const struct nft_set_ops *ops; + u32 features; + +#ifdef CONFIG_MODULES + if (list_empty(&nf_tables_set_ops)) { + nfnl_unlock(NFNL_SUBSYS_NFTABLES); + request_module("nft-set"); + nfnl_lock(NFNL_SUBSYS_NFTABLES); + if (!list_empty(&nf_tables_set_ops)) + return ERR_PTR(-EAGAIN); + } +#endif + features = 0; + if (nla[NFTA_SET_FLAGS] != NULL) { + features = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS])); + features &= NFT_SET_INTERVAL | NFT_SET_MAP; + } + + // FIXME: implement selection properly + list_for_each_entry(ops, &nf_tables_set_ops, list) { + if ((ops->features & features) != features) + continue; + if (!try_module_get(ops->owner)) + continue; + return ops; + } + + return ERR_PTR(-EOPNOTSUPP); +} + +static const struct nla_policy nft_set_policy[NFTA_SET_MAX + 1] = { + [NFTA_SET_TABLE] = { .type = NLA_STRING }, + [NFTA_SET_NAME] = { .type = NLA_STRING }, + [NFTA_SET_FLAGS] = { .type = NLA_U32 }, + [NFTA_SET_KEY_TYPE] = { .type = NLA_U32 }, + [NFTA_SET_KEY_LEN] = { .type = NLA_U32 }, + [NFTA_SET_DATA_TYPE] = { .type = NLA_U32 }, + [NFTA_SET_DATA_LEN] = { .type = NLA_U32 }, +}; + +static int nft_ctx_init_from_setattr(struct nft_ctx *ctx, + const 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; + const struct nft_table *table = NULL; + + afi = nf_tables_afinfo_lookup(nfmsg->nfgen_family, false); + if (IS_ERR(afi)) + return PTR_ERR(afi); + + if (nla[NFTA_SET_TABLE] != NULL) { + table = nf_tables_table_lookup(afi, nla[NFTA_SET_TABLE], false); + if (IS_ERR(table)) + return PTR_ERR(table); + } + + nft_ctx_init(ctx, skb, nlh, afi, table, NULL); + return 0; +} + +struct nft_set *nf_tables_set_lookup(const struct nft_table *table, + const struct nlattr *nla) +{ + struct nft_set *set; + + if (nla == NULL) + return ERR_PTR(-EINVAL); + + list_for_each_entry(set, &table->sets, list) { + if (!nla_strcmp(nla, set->name)) + return set; + } + return ERR_PTR(-ENOENT); +} + +static int nf_tables_set_alloc_name(struct nft_ctx *ctx, struct nft_set *set, + const char *name) +{ + const struct nft_set *i; + const char *p; + unsigned long *inuse; + unsigned int n = 0; + + p = strnchr(name, IFNAMSIZ, '%'); + if (p != NULL) { + if (p[1] != 'd' || strchr(p + 2, '%')) + return -EINVAL; + + inuse = (unsigned long *)get_zeroed_page(GFP_KERNEL); + if (inuse == NULL) + return -ENOMEM; + + list_for_each_entry(i, &ctx->table->sets, list) { + if (!sscanf(i->name, name, &n)) + continue; + if (n < 0 || n > BITS_PER_LONG * PAGE_SIZE) + continue; + set_bit(n, inuse); + } + + n = find_first_zero_bit(inuse, BITS_PER_LONG * PAGE_SIZE); + free_page((unsigned long)inuse); + } + + snprintf(set->name, sizeof(set->name), name, n); + list_for_each_entry(i, &ctx->table->sets, list) { + if (!strcmp(set->name, i->name)) + return -ENFILE; + } + return 0; +} + +static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx, + const struct nft_set *set, u16 event, u16 flags) +{ + struct nfgenmsg *nfmsg; + struct nlmsghdr *nlh; + u32 portid = NETLINK_CB(ctx->skb).portid; + u32 seq = ctx->nlh->nlmsg_seq; + + event |= NFNL_SUBSYS_NFTABLES << 8; + nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), + flags); + if (nlh == NULL) + goto nla_put_failure; + + nfmsg = nlmsg_data(nlh); + nfmsg->nfgen_family = ctx->afi->family; + nfmsg->version = NFNETLINK_V0; + nfmsg->res_id = 0; + + if (nla_put_string(skb, NFTA_SET_TABLE, ctx->table->name)) + goto nla_put_failure; + if (nla_put_string(skb, NFTA_SET_NAME, set->name)) + goto nla_put_failure; + if (set->flags != 0) + if (nla_put_be32(skb, NFTA_SET_FLAGS, htonl(set->flags))) + goto nla_put_failure; + + if (nla_put_be32(skb, NFTA_SET_KEY_TYPE, htonl(set->ktype))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_SET_KEY_LEN, htonl(set->klen))) + goto nla_put_failure; + if (set->flags & NFT_SET_MAP) { + if (nla_put_be32(skb, NFTA_SET_DATA_TYPE, htonl(set->dtype))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_SET_DATA_LEN, htonl(set->dlen))) + goto nla_put_failure; + } + + return nlmsg_end(skb, nlh); + +nla_put_failure: + nlmsg_trim(skb, nlh); + return -1; +} + +static int nf_tables_set_notify(const struct nft_ctx *ctx, + const struct nft_set *set, + int event) +{ + struct sk_buff *skb; + u32 portid = NETLINK_CB(ctx->skb).portid; + struct net *net = sock_net(ctx->skb->sk); + bool report; + int err; + + report = nlmsg_report(ctx->nlh); + if (!report && !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES)) + return 0; + + err = -ENOBUFS; + skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + if (skb == NULL) + goto err; + + err = nf_tables_fill_set(skb, ctx, set, event, 0); + if (err < 0) { + kfree_skb(skb); + goto err; + } + + err = nfnetlink_send(skb, net, portid, NFNLGRP_NFTABLES, report, + GFP_KERNEL); +err: + if (err < 0) + nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, err); + return err; +} + +static int nf_tables_dump_sets_table(struct nft_ctx *ctx, struct sk_buff *skb, + struct netlink_callback *cb) +{ + const struct nft_set *set; + unsigned int idx = 0, s_idx = cb->args[0]; + + if (cb->args[1]) + return skb->len; + + list_for_each_entry(set, &ctx->table->sets, list) { + if (idx < s_idx) + goto cont; + if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET, + NLM_F_MULTI) < 0) { + cb->args[0] = idx; + goto done; + } +cont: + idx++; + } + cb->args[1] = 1; +done: + return skb->len; +} + +static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb, + struct netlink_callback *cb) +{ + const struct nft_set *set; + unsigned int idx = 0, s_idx = cb->args[0]; + struct nft_table *table, *cur_table = (struct nft_table *)cb->args[2]; + + if (cb->args[1]) + return skb->len; + + list_for_each_entry(table, &ctx->afi->tables, list) { + if (cur_table && cur_table != table) + continue; + + ctx->table = table; + list_for_each_entry(set, &ctx->table->sets, list) { + if (idx < s_idx) + goto cont; + if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET, + NLM_F_MULTI) < 0) { + cb->args[0] = idx; + cb->args[2] = (unsigned long) table; + goto done; + } +cont: + idx++; + } + } + cb->args[1] = 1; +done: + return skb->len; +} + +static int nf_tables_dump_sets(struct sk_buff *skb, struct netlink_callback *cb) +{ + const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh); + struct nlattr *nla[NFTA_SET_MAX + 1]; + struct nft_ctx ctx; + int err, ret; + + err = nlmsg_parse(cb->nlh, sizeof(*nfmsg), nla, NFTA_SET_MAX, + nft_set_policy); + if (err < 0) + return err; + + err = nft_ctx_init_from_setattr(&ctx, cb->skb, cb->nlh, (void *)nla); + if (err < 0) + return err; + + if (ctx.table == NULL) + ret = nf_tables_dump_sets_all(&ctx, skb, cb); + else + ret = nf_tables_dump_sets_table(&ctx, skb, cb); + + return ret; +} + +static int nf_tables_getset(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + const struct nft_set *set; + struct nft_ctx ctx; + struct sk_buff *skb2; + int err; + + /* Verify existance before starting dump */ + err = nft_ctx_init_from_setattr(&ctx, skb, nlh, nla); + if (err < 0) + return err; + + if (nlh->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .dump = nf_tables_dump_sets, + }; + return netlink_dump_start(nlsk, skb, nlh, &c); + } + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]); + if (IS_ERR(set)) + return PTR_ERR(set); + + skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); + if (skb2 == NULL) + return -ENOMEM; + + err = nf_tables_fill_set(skb2, &ctx, set, NFT_MSG_NEWSET, 0); + if (err < 0) + goto err; + + return nlmsg_unicast(nlsk, skb2, NETLINK_CB(skb).portid); + +err: + kfree_skb(skb2); + return err; +} + +static int nf_tables_newset(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_set_ops *ops; + const struct nft_af_info *afi; + struct nft_table *table; + struct nft_set *set; + struct nft_ctx ctx; + char name[IFNAMSIZ]; + unsigned int size; + bool create; + u32 ktype, klen, dlen, dtype, flags; + int err; + + if (nla[NFTA_SET_TABLE] == NULL || + nla[NFTA_SET_NAME] == NULL || + nla[NFTA_SET_KEY_LEN] == NULL) + return -EINVAL; + + ktype = NFT_DATA_VALUE; + if (nla[NFTA_SET_KEY_TYPE] != NULL) { + ktype = ntohl(nla_get_be32(nla[NFTA_SET_KEY_TYPE])); + if ((ktype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK) + return -EINVAL; + } + + klen = ntohl(nla_get_be32(nla[NFTA_SET_KEY_LEN])); + if (klen == 0 || klen > FIELD_SIZEOF(struct nft_data, data)) + return -EINVAL; + + flags = 0; + if (nla[NFTA_SET_FLAGS] != NULL) { + flags = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS])); + if (flags & ~(NFT_SET_ANONYMOUS | NFT_SET_CONSTANT | + NFT_SET_INTERVAL | NFT_SET_MAP)) + return -EINVAL; + } + + dtype = 0; + dlen = 0; + if (nla[NFTA_SET_DATA_TYPE] != NULL) { + if (!(flags & NFT_SET_MAP)) + return -EINVAL; + + dtype = ntohl(nla_get_be32(nla[NFTA_SET_DATA_TYPE])); + if ((dtype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK && + dtype != NFT_DATA_VERDICT) + return -EINVAL; + + if (dtype != NFT_DATA_VERDICT) { + if (nla[NFTA_SET_DATA_LEN] == NULL) + return -EINVAL; + dlen = ntohl(nla_get_be32(nla[NFTA_SET_DATA_LEN])); + if (dlen == 0 || + dlen > FIELD_SIZEOF(struct nft_data, data)) + return -EINVAL; + } else + dlen = sizeof(struct nft_data); + } else if (flags & NFT_SET_MAP) + return -EINVAL; + + create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false; + + afi = nf_tables_afinfo_lookup(nfmsg->nfgen_family, create); + if (IS_ERR(afi)) + return PTR_ERR(afi); + + table = nf_tables_table_lookup(afi, nla[NFTA_SET_TABLE], create); + if (IS_ERR(table)) + return PTR_ERR(table); + + nft_ctx_init(&ctx, skb, nlh, afi, table, NULL); + + set = nf_tables_set_lookup(table, nla[NFTA_SET_NAME]); + if (IS_ERR(set)) { + if (PTR_ERR(set) != -ENOENT) + return PTR_ERR(set); + set = NULL; + } + + if (set != NULL) { + if (nlh->nlmsg_flags & NLM_F_EXCL) + return -EEXIST; + if (nlh->nlmsg_flags & NLM_F_REPLACE) + return -EOPNOTSUPP; + return 0; + } + + if (!(nlh->nlmsg_flags & NLM_F_CREATE)) + return -ENOENT; + + ops = nft_select_set_ops(nla); + if (IS_ERR(ops)) + return PTR_ERR(ops); + + size = 0; + if (ops->privsize != NULL) + size = ops->privsize(nla); + + err = -ENOMEM; + set = kzalloc(sizeof(*set) + size, GFP_KERNEL); + if (set == NULL) + goto err1; + + nla_strlcpy(name, nla[NFTA_SET_NAME], sizeof(set->name)); + err = nf_tables_set_alloc_name(&ctx, set, name); + if (err < 0) + goto err2; + + INIT_LIST_HEAD(&set->bindings); + set->ops = ops; + set->ktype = ktype; + set->klen = klen; + set->dtype = dtype; + set->dlen = dlen; + set->flags = flags; + + err = ops->init(set, nla); + if (err < 0) + goto err2; + + list_add_tail(&set->list, &table->sets); + nf_tables_set_notify(&ctx, set, NFT_MSG_NEWSET); + return 0; + +err2: + kfree(set); +err1: + module_put(ops->owner); + return err; +} + +static void nf_tables_set_destroy(const struct nft_ctx *ctx, struct nft_set *set) +{ + list_del(&set->list); + if (!(set->flags & NFT_SET_ANONYMOUS)) + nf_tables_set_notify(ctx, set, NFT_MSG_DELSET); + + set->ops->destroy(set); + module_put(set->ops->owner); + kfree(set); +} + +static int nf_tables_delset(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + struct nft_set *set; + struct nft_ctx ctx; + int err; + + if (nla[NFTA_SET_TABLE] == NULL) + return -EINVAL; + + err = nft_ctx_init_from_setattr(&ctx, skb, nlh, nla); + if (err < 0) + return err; + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]); + if (IS_ERR(set)) + return PTR_ERR(set); + if (!list_empty(&set->bindings)) + return -EBUSY; + + nf_tables_set_destroy(&ctx, set); + return 0; +} + +static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx, + const struct nft_set *set, + const struct nft_set_iter *iter, + const struct nft_set_elem *elem) +{ + enum nft_registers dreg; + + dreg = nft_type_to_reg(set->dtype); + return nft_validate_data_load(ctx, dreg, &elem->data, set->dtype); +} + +int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set, + struct nft_set_binding *binding) +{ + struct nft_set_binding *i; + struct nft_set_iter iter; + + if (!list_empty(&set->bindings) && set->flags & NFT_SET_ANONYMOUS) + return -EBUSY; + + if (set->flags & NFT_SET_MAP) { + /* If the set is already bound to the same chain all + * jumps are already validated for that chain. + */ + list_for_each_entry(i, &set->bindings, list) { + if (i->chain == binding->chain) + goto bind; + } + + iter.skip = 0; + iter.count = 0; + iter.err = 0; + iter.fn = nf_tables_bind_check_setelem; + + set->ops->walk(ctx, set, &iter); + if (iter.err < 0) { + /* Destroy anonymous sets if binding fails */ + if (set->flags & NFT_SET_ANONYMOUS) + nf_tables_set_destroy(ctx, set); + + return iter.err; + } + } +bind: + binding->chain = ctx->chain; + list_add_tail(&binding->list, &set->bindings); + return 0; +} + +void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set, + struct nft_set_binding *binding) +{ + list_del(&binding->list); + + if (list_empty(&set->bindings) && set->flags & NFT_SET_ANONYMOUS) + nf_tables_set_destroy(ctx, set); +} + +/* + * Set elements + */ + +static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = { + [NFTA_SET_ELEM_KEY] = { .type = NLA_NESTED }, + [NFTA_SET_ELEM_DATA] = { .type = NLA_NESTED }, + [NFTA_SET_ELEM_FLAGS] = { .type = NLA_U32 }, +}; + +static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = { + [NFTA_SET_ELEM_LIST_TABLE] = { .type = NLA_STRING }, + [NFTA_SET_ELEM_LIST_SET] = { .type = NLA_STRING }, + [NFTA_SET_ELEM_LIST_ELEMENTS] = { .type = NLA_NESTED }, +}; + +static int nft_ctx_init_from_elemattr(struct nft_ctx *ctx, + const 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; + const struct nft_table *table; + + afi = nf_tables_afinfo_lookup(nfmsg->nfgen_family, false); + if (IS_ERR(afi)) + return PTR_ERR(afi); + + table = nf_tables_table_lookup(afi, nla[NFTA_SET_ELEM_LIST_TABLE], false); + if (IS_ERR(table)) + return PTR_ERR(table); + + nft_ctx_init(ctx, skb, nlh, afi, table, NULL); + return 0; +} + +static int nf_tables_fill_setelem(struct sk_buff *skb, + const struct nft_set *set, + const struct nft_set_elem *elem) +{ + unsigned char *b = skb_tail_pointer(skb); + struct nlattr *nest; + + nest = nla_nest_start(skb, NFTA_LIST_ELEM); + if (nest == NULL) + goto nla_put_failure; + + if (nft_data_dump(skb, NFTA_SET_ELEM_KEY, &elem->key, NFT_DATA_VALUE, + set->klen) < 0) + goto nla_put_failure; + + if (set->flags & NFT_SET_MAP && + !(elem->flags & NFT_SET_ELEM_INTERVAL_END) && + nft_data_dump(skb, NFTA_SET_ELEM_DATA, &elem->data, + set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE, + set->dlen) < 0) + goto nla_put_failure; + + if (elem->flags != 0) + if (nla_put_be32(skb, NFTA_SET_ELEM_FLAGS, htonl(elem->flags))) + goto nla_put_failure; + + nla_nest_end(skb, nest); + return 0; + +nla_put_failure: + nlmsg_trim(skb, b); + return -EMSGSIZE; +} + +struct nft_set_dump_args { + const struct netlink_callback *cb; + struct nft_set_iter iter; + struct sk_buff *skb; +}; + +static int nf_tables_dump_setelem(const struct nft_ctx *ctx, + const struct nft_set *set, + const struct nft_set_iter *iter, + const struct nft_set_elem *elem) +{ + struct nft_set_dump_args *args; + + args = container_of(iter, struct nft_set_dump_args, iter); + return nf_tables_fill_setelem(args->skb, set, elem); +} + +static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) +{ + const struct nft_set *set; + struct nft_set_dump_args args; + struct nft_ctx ctx; + struct nlattr *nla[NFTA_SET_ELEM_LIST_MAX + 1]; + struct nfgenmsg *nfmsg; + struct nlmsghdr *nlh; + struct nlattr *nest; + u32 portid, seq; + int event, err; + + nfmsg = nlmsg_data(cb->nlh); + err = nlmsg_parse(cb->nlh, sizeof(*nfmsg), nla, NFTA_SET_ELEM_LIST_MAX, + nft_set_elem_list_policy); + if (err < 0) + return err; + + err = nft_ctx_init_from_elemattr(&ctx, cb->skb, cb->nlh, (void *)nla); + if (err < 0) + return err; + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]); + if (IS_ERR(set)) + return PTR_ERR(set); + + event = NFT_MSG_NEWSETELEM; + event |= NFNL_SUBSYS_NFTABLES << 8; + portid = NETLINK_CB(cb->skb).portid; + seq = cb->nlh->nlmsg_seq; + + nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), + NLM_F_MULTI); + if (nlh == NULL) + goto nla_put_failure; + + nfmsg = nlmsg_data(nlh); + nfmsg->nfgen_family = NFPROTO_UNSPEC; + nfmsg->version = NFNETLINK_V0; + nfmsg->res_id = 0; + + if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, ctx.table->name)) + goto nla_put_failure; + if (nla_put_string(skb, NFTA_SET_ELEM_LIST_SET, set->name)) + goto nla_put_failure; + + nest = nla_nest_start(skb, NFTA_SET_ELEM_LIST_ELEMENTS); + if (nest == NULL) + goto nla_put_failure; + + args.cb = cb; + args.skb = skb; + args.iter.skip = cb->args[0]; + args.iter.count = 0; + args.iter.err = 0; + args.iter.fn = nf_tables_dump_setelem; + set->ops->walk(&ctx, set, &args.iter); + + nla_nest_end(skb, nest); + nlmsg_end(skb, nlh); + + if (args.iter.err && args.iter.err != -EMSGSIZE) + return args.iter.err; + if (args.iter.count == cb->args[0]) + return 0; + + cb->args[0] = args.iter.count; + return skb->len; + +nla_put_failure: + return -ENOSPC; +} + +static int nf_tables_getsetelem(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + const struct nft_set *set; + struct nft_ctx ctx; + int err; + + err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla); + if (err < 0) + return err; + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]); + if (IS_ERR(set)) + return PTR_ERR(set); + + if (nlh->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .dump = nf_tables_dump_set, + }; + return netlink_dump_start(nlsk, skb, nlh, &c); + } + return -EOPNOTSUPP; +} + +static int nft_add_set_elem(const struct nft_ctx *ctx, struct nft_set *set, + const struct nlattr *attr) +{ + struct nlattr *nla[NFTA_SET_ELEM_MAX + 1]; + struct nft_data_desc d1, d2; + struct nft_set_elem elem; + struct nft_set_binding *binding; + enum nft_registers dreg; + int err; + + err = nla_parse_nested(nla, NFTA_SET_ELEM_MAX, attr, + nft_set_elem_policy); + if (err < 0) + return err; + + if (nla[NFTA_SET_ELEM_KEY] == NULL) + return -EINVAL; + + elem.flags = 0; + if (nla[NFTA_SET_ELEM_FLAGS] != NULL) { + elem.flags = ntohl(nla_get_be32(nla[NFTA_SET_ELEM_FLAGS])); + if (elem.flags & ~NFT_SET_ELEM_INTERVAL_END) + return -EINVAL; + } + + if (set->flags & NFT_SET_MAP) { + if (nla[NFTA_SET_ELEM_DATA] == NULL && + !(elem.flags & NFT_SET_ELEM_INTERVAL_END)) + return -EINVAL; + } else { + if (nla[NFTA_SET_ELEM_DATA] != NULL) + return -EINVAL; + } + + err = nft_data_init(ctx, &elem.key, &d1, nla[NFTA_SET_ELEM_KEY]); + if (err < 0) + goto err1; + err = -EINVAL; + if (d1.type != NFT_DATA_VALUE || d1.len != set->klen) + goto err2; + + err = -EEXIST; + if (set->ops->get(set, &elem) == 0) + goto err2; + + if (nla[NFTA_SET_ELEM_DATA] != NULL) { + err = nft_data_init(ctx, &elem.data, &d2, nla[NFTA_SET_ELEM_DATA]); + if (err < 0) + goto err2; + + err = -EINVAL; + if (set->dtype != NFT_DATA_VERDICT && d2.len != set->dlen) + goto err3; + + dreg = nft_type_to_reg(set->dtype); + list_for_each_entry(binding, &set->bindings, list) { + struct nft_ctx bind_ctx = { + .afi = ctx->afi, + .table = ctx->table, + .chain = binding->chain, + }; + + err = nft_validate_data_load(&bind_ctx, dreg, + &elem.data, d2.type); + if (err < 0) + goto err3; + } + } + + err = set->ops->insert(set, &elem); + if (err < 0) + goto err3; + + return 0; + +err3: + if (nla[NFTA_SET_ELEM_DATA] != NULL) + nft_data_uninit(&elem.data, d2.type); +err2: + nft_data_uninit(&elem.key, d1.type); +err1: + return err; +} + +static int nf_tables_newsetelem(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + const struct nlattr *attr; + struct nft_set *set; + struct nft_ctx ctx; + int rem, err; + + err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla); + if (err < 0) + return err; + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]); + if (IS_ERR(set)) + return PTR_ERR(set); + if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT) + return -EBUSY; + + nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) { + err = nft_add_set_elem(&ctx, set, attr); + if (err < 0) + return err; + } + return 0; +} + +static int nft_del_setelem(const struct nft_ctx *ctx, struct nft_set *set, + const struct nlattr *attr) +{ + struct nlattr *nla[NFTA_SET_ELEM_MAX + 1]; + struct nft_data_desc desc; + struct nft_set_elem elem; + int err; + + err = nla_parse_nested(nla, NFTA_SET_ELEM_MAX, attr, + nft_set_elem_policy); + if (err < 0) + goto err1; + + err = -EINVAL; + if (nla[NFTA_SET_ELEM_KEY] == NULL) + goto err1; + + err = nft_data_init(ctx, &elem.key, &desc, nla[NFTA_SET_ELEM_KEY]); + if (err < 0) + goto err1; + + err = -EINVAL; + if (desc.type != NFT_DATA_VALUE || desc.len != set->klen) + goto err2; + + err = set->ops->get(set, &elem); + if (err < 0) + goto err2; + + set->ops->remove(set, &elem); + + nft_data_uninit(&elem.key, NFT_DATA_VALUE); + if (set->flags & NFT_SET_MAP) + nft_data_uninit(&elem.data, set->dtype); + +err2: + nft_data_uninit(&elem.key, desc.type); +err1: + return err; +} + +static int nf_tables_delsetelem(struct sock *nlsk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + const struct nlattr * const nla[]) +{ + const struct nlattr *attr; + struct nft_set *set; + struct nft_ctx ctx; + int rem, err; + + err = nft_ctx_init_from_elemattr(&ctx, skb, nlh, nla); + if (err < 0) + return err; + + set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET]); + if (IS_ERR(set)) + return PTR_ERR(set); + if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT) + return -EBUSY; + + nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) { + err = nft_del_setelem(&ctx, set, attr); + if (err < 0) + return err; + } + return 0; +} + static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = { [NFT_MSG_NEWTABLE] = { .call = nf_tables_newtable, @@ -1438,6 +2377,36 @@ static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = { .attr_count = NFTA_RULE_MAX, .policy = nft_rule_policy, }, + [NFT_MSG_NEWSET] = { + .call = nf_tables_newset, + .attr_count = NFTA_SET_MAX, + .policy = nft_set_policy, + }, + [NFT_MSG_GETSET] = { + .call = nf_tables_getset, + .attr_count = NFTA_SET_MAX, + .policy = nft_set_policy, + }, + [NFT_MSG_DELSET] = { + .call = nf_tables_delset, + .attr_count = NFTA_SET_MAX, + .policy = nft_set_policy, + }, + [NFT_MSG_NEWSETELEM] = { + .call = nf_tables_newsetelem, + .attr_count = NFTA_SET_ELEM_LIST_MAX, + .policy = nft_set_elem_list_policy, + }, + [NFT_MSG_GETSETELEM] = { + .call = nf_tables_getsetelem, + .attr_count = NFTA_SET_ELEM_LIST_MAX, + .policy = nft_set_elem_list_policy, + }, + [NFT_MSG_DELSETELEM] = { + .call = nf_tables_delsetelem, + .attr_count = NFTA_SET_ELEM_LIST_MAX, + .policy = nft_set_elem_list_policy, + }, }; static const struct nfnetlink_subsystem nf_tables_subsys = { @@ -1447,6 +2416,90 @@ static const struct nfnetlink_subsystem nf_tables_subsys = { .cb = nf_tables_cb, }; +/* + * Loop detection - walk through the ruleset beginning at the destination chain + * of a new jump until either the source chain is reached (loop) or all + * reachable chains have been traversed. + * + * The loop check is performed whenever a new jump verdict is added to an + * expression or verdict map or a verdict map is bound to a new chain. + */ + +static int nf_tables_check_loops(const struct nft_ctx *ctx, + const struct nft_chain *chain); + +static int nf_tables_loop_check_setelem(const struct nft_ctx *ctx, + const struct nft_set *set, + const struct nft_set_iter *iter, + const struct nft_set_elem *elem) +{ + switch (elem->data.verdict) { + case NFT_JUMP: + case NFT_GOTO: + return nf_tables_check_loops(ctx, elem->data.chain); + default: + return 0; + } +} + +static int nf_tables_check_loops(const struct nft_ctx *ctx, + const struct nft_chain *chain) +{ + const struct nft_rule *rule; + const struct nft_expr *expr, *last; + const struct nft_data *data; + const struct nft_set *set; + struct nft_set_binding *binding; + struct nft_set_iter iter; + int err; + + if (ctx->chain == chain) + return -ELOOP; + + list_for_each_entry(rule, &chain->rules, list) { + nft_rule_for_each_expr(expr, last, rule) { + if (!expr->ops->get_verdict) + continue; + + data = expr->ops->get_verdict(expr); + if (data == NULL) + break; + + switch (data->verdict) { + case NFT_JUMP: + case NFT_GOTO: + err = nf_tables_check_loops(ctx, data->chain); + if (err < 0) + return err; + default: + break; + } + } + } + + list_for_each_entry(set, &ctx->table->sets, list) { + if (!(set->flags & NFT_SET_MAP) || + set->dtype != NFT_DATA_VERDICT) + continue; + + list_for_each_entry(binding, &set->bindings, list) { + if (binding->chain != chain) + continue; + + iter.skip = 0; + iter.count = 0; + iter.err = 0; + iter.fn = nf_tables_loop_check_setelem; + + set->ops->walk(ctx, set, &iter); + if (iter.err < 0) + return iter.err; + } + } + + return 0; +} + /** * nft_validate_input_register - validate an expressions' input register * @@ -1500,11 +2553,25 @@ int nft_validate_data_load(const struct nft_ctx *ctx, enum nft_registers reg, const struct nft_data *data, enum nft_data_types type) { + int err; + switch (reg) { case NFT_REG_VERDICT: if (data == NULL || type != NFT_DATA_VERDICT) return -EINVAL; - // FIXME: do loop detection + + if (data->verdict == NFT_GOTO || data->verdict == NFT_JUMP) { + err = nf_tables_check_loops(ctx, data->chain); + if (err < 0) + return err; + + if (ctx->chain->level + 1 > data->chain->level) { + if (ctx->chain->level + 1 == NFT_JUMP_STACK_SIZE) + return -EMLINK; + data->chain->level = ctx->chain->level + 1; + } + } + return 0; default: if (data != NULL && type != NFT_DATA_VALUE) @@ -1555,11 +2622,6 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data, if (chain->flags & NFT_BASE_CHAIN) return -EOPNOTSUPP; - if (ctx->chain->level + 1 > chain->level) { - if (ctx->chain->level + 1 == 16) - return -EMLINK; - chain->level = ctx->chain->level + 1; - } chain->use++; data->chain = chain; desc->len = sizeof(data); |