netfilter: nf_tables: dump sets in all existing families

This patch allows you to dump all sets available in all of
the registered families. This allows you to use NFPROTO_UNSPEC
to dump all existing sets, similarly to other existing table,
chain and rule operations.

This patch is based on original patch from Arturo Borrero
González.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 78 insertions, 9 deletions

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 37f0e6988ec4..0d4b42df3350 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1904,12 +1904,14 @@ static int nft_ctx_init_from_setattr(struct nft_ctx *ctx,
 {
         struct net *net = sock_net(skb->sk);
         const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
-        const struct nft_af_info *afi;
+        const struct nft_af_info *afi = NULL;
         const struct nft_table *table = NULL;
 
-        afi = nf_tables_afinfo_lookup(net, nfmsg->nfgen_family, false);
-        if (IS_ERR(afi))
-                return PTR_ERR(afi);
+        if (nfmsg->nfgen_family != NFPROTO_UNSPEC) {
+                afi = nf_tables_afinfo_lookup(net, 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]);
@@ -2078,8 +2080,8 @@ done:
         return skb->len;
 }
 
-static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
-                                   struct netlink_callback *cb)
+static int nf_tables_dump_sets_family(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];
@@ -2111,6 +2113,61 @@ 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, s_idx = cb->args[0];
+        const struct nft_af_info *afi;
+        struct nft_table *table, *cur_table = (struct nft_table *)cb->args[2];
+        struct net *net = sock_net(skb->sk);
+        int cur_family = cb->args[3];
+
+        if (cb->args[1])
+                return skb->len;
+
+        list_for_each_entry(afi, &net->nft.af_info, list) {
+                if (cur_family) {
+                        if (afi->family != cur_family)
+                                continue;
+
+                        cur_family = 0;
+                }
+
+                list_for_each_entry(table, &afi->tables, list) {
+                        if (cur_table) {
+                                if (cur_table != table)
+                                        continue;
+
+                                cur_table = NULL;
+                        }
+
+                        ctx->table = table;
+                        ctx->afi = afi;
+                        idx = 0;
+                        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;
+                                        cb->args[3] = afi->family;
+                                        goto done;
+                                }
+cont:
+                                idx++;
+                        }
+                        if (s_idx)
+                                s_idx = 0;
+                }
+        }
+        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);
@@ -2127,9 +2184,12 @@ static int nf_tables_dump_sets(struct sk_buff *skb, struct netlink_callback *cb)
         if (err < 0)
                 return err;
 
-        if (ctx.table == NULL)
-                ret = nf_tables_dump_sets_all(&ctx, skb, cb);
-        else
+        if (ctx.table == NULL) {
+                if (ctx.afi == NULL)
+                        ret = nf_tables_dump_sets_all(&ctx, skb, cb);
+                else
+                        ret = nf_tables_dump_sets_family(&ctx, skb, cb);
+        } else
                 ret = nf_tables_dump_sets_table(&ctx, skb, cb);
 
         return ret;
@@ -2142,6 +2202,7 @@ static int nf_tables_getset(struct sock *nlsk, struct sk_buff *skb,
         const struct nft_set *set;
         struct nft_ctx ctx;
         struct sk_buff *skb2;
+        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
         int err;
 
         /* Verify existance before starting dump */
@@ -2156,6 +2217,10 @@ static int nf_tables_getset(struct sock *nlsk, struct sk_buff *skb,
                 return netlink_dump_start(nlsk, skb, nlh, &c);
         }
 
+        /* Only accept unspec with dump */
+        if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
+                return -EAFNOSUPPORT;
+
         set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]);
         if (IS_ERR(set))
                 return PTR_ERR(set);
@@ -2325,6 +2390,7 @@ static int nf_tables_delset(struct sock *nlsk, struct sk_buff *skb,
                             const struct nlmsghdr *nlh,
                             const struct nlattr * const nla[])
 {
+        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
         struct nft_set *set;
         struct nft_ctx ctx;
         int err;
@@ -2336,6 +2402,9 @@ static int nf_tables_delset(struct sock *nlsk, struct sk_buff *skb,
         if (err < 0)
                 return err;
 
+        if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
+                return -EAFNOSUPPORT;
+
         set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME]);
         if (IS_ERR(set))
                 return PTR_ERR(set);