netfilter: add helper function to set up the nfnetlink header and use it

This patch adds a helper function to set up the netlink and nfnetlink headers.
Update existing codebase to use it.

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

1 files changed, 27 insertions, 75 deletions

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index e894d70b5d5f..005f1c620fc0 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -707,18 +707,13 @@ static int nf_tables_fill_table_info(struct sk_buff *skb, struct net *net,
 				     int family, const struct nft_table *table)
 {
 	struct nlmsghdr *nlh;
-	struct nfgenmsg *nfmsg;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
+			   NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_TABLE_NAME, table->name) ||
 	    nla_put_be32(skb, NFTA_TABLE_FLAGS, htonl(table->flags)) ||
 	    nla_put_be32(skb, NFTA_TABLE_USE, htonl(table->use)) ||
@@ -1468,18 +1463,13 @@ static int nf_tables_fill_chain_info(struct sk_buff *skb, struct net *net,
 				     const struct nft_chain *chain)
 {
 	struct nlmsghdr *nlh;
-	struct nfgenmsg *nfmsg;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
+			   NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_CHAIN_TABLE, table->name))
 		goto nla_put_failure;
 	if (nla_put_be64(skb, NFTA_CHAIN_HANDLE, cpu_to_be64(chain->handle),
@@ -2825,20 +2815,15 @@ static int nf_tables_fill_rule_info(struct sk_buff *skb, struct net *net,
 				    const struct nft_rule *prule)
 {
 	struct nlmsghdr *nlh;
-	struct nfgenmsg *nfmsg;
 	const struct nft_expr *expr, *next;
 	struct nlattr *list;
 	u16 type = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
 
-	nlh = nlmsg_put(skb, portid, seq, type, sizeof(struct nfgenmsg), flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, type, flags, family, NFNETLINK_V0,
+			   nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_RULE_TABLE, table->name))
 		goto nla_put_failure;
 	if (nla_put_string(skb, NFTA_RULE_CHAIN, chain->name))
@@ -3809,7 +3794,6 @@ static int nf_tables_fill_set_concat(struct sk_buff *skb,
 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 = ctx->portid;
 	struct nlattr *nest;
@@ -3817,16 +3801,11 @@ static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
 	int i;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg),
-			flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, ctx->family,
+			   NFNETLINK_V0, nft_base_seq(ctx->net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= ctx->family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(ctx->net);
-
 	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))
@@ -4795,7 +4774,6 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
 	struct nft_set *set;
 	struct nft_set_dump_args args;
 	bool set_found = false;
-	struct nfgenmsg *nfmsg;
 	struct nlmsghdr *nlh;
 	struct nlattr *nest;
 	u32 portid, seq;
@@ -4828,16 +4806,11 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
 	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)
+	nlh = nfnl_msg_put(skb, portid, seq, event, NLM_F_MULTI,
+			   table->family, NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family = table->family;
-	nfmsg->version      = NFNETLINK_V0;
-	nfmsg->res_id	    = nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, table->name))
 		goto nla_put_failure;
 	if (nla_put_string(skb, NFTA_SET_ELEM_LIST_SET, set->name))
@@ -4894,22 +4867,16 @@ static int nf_tables_fill_setelem_info(struct sk_buff *skb,
 				       const struct nft_set *set,
 				       const struct nft_set_elem *elem)
 {
-	struct nfgenmsg *nfmsg;
 	struct nlmsghdr *nlh;
 	struct nlattr *nest;
 	int err;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg),
-			flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, ctx->family,
+			   NFNETLINK_V0, nft_base_seq(ctx->net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= ctx->family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(ctx->net);
-
 	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))
@@ -6227,19 +6194,14 @@ static int nf_tables_fill_obj_info(struct sk_buff *skb, struct net *net,
 				   int family, const struct nft_table *table,
 				   struct nft_object *obj, bool reset)
 {
-	struct nfgenmsg *nfmsg;
 	struct nlmsghdr *nlh;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
+			   NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_OBJ_TABLE, table->name) ||
 	    nla_put_string(skb, NFTA_OBJ_NAME, obj->key.name) ||
 	    nla_put_be32(skb, NFTA_OBJ_TYPE, htonl(obj->ops->type->type)) ||
@@ -7139,20 +7101,15 @@ static int nf_tables_fill_flowtable_info(struct sk_buff *skb, struct net *net,
 					 struct list_head *hook_list)
 {
 	struct nlattr *nest, *nest_devs;
-	struct nfgenmsg *nfmsg;
 	struct nft_hook *hook;
 	struct nlmsghdr *nlh;
 
 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), flags);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
+			   NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= family;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_string(skb, NFTA_FLOWTABLE_TABLE, flowtable->table->name) ||
 	    nla_put_string(skb, NFTA_FLOWTABLE_NAME, flowtable->name) ||
 	    nla_put_be32(skb, NFTA_FLOWTABLE_USE, htonl(flowtable->use)) ||
@@ -7385,19 +7342,14 @@ static int nf_tables_fill_gen_info(struct sk_buff *skb, struct net *net,
 				   u32 portid, u32 seq)
 {
 	struct nlmsghdr *nlh;
-	struct nfgenmsg *nfmsg;
 	char buf[TASK_COMM_LEN];
 	int event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWGEN);
 
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg), 0);
-	if (nlh == NULL)
+	nlh = nfnl_msg_put(skb, portid, seq, event, 0, AF_UNSPEC,
+			   NFNETLINK_V0, nft_base_seq(net));
+	if (!nlh)
 		goto nla_put_failure;
 
-	nfmsg = nlmsg_data(nlh);
-	nfmsg->nfgen_family	= AF_UNSPEC;
-	nfmsg->version		= NFNETLINK_V0;
-	nfmsg->res_id		= nft_base_seq(net);
-
 	if (nla_put_be32(skb, NFTA_GEN_ID, htonl(net->nft.base_seq)) ||
 	    nla_put_be32(skb, NFTA_GEN_PROC_PID, htonl(task_pid_nr(current))) ||
 	    nla_put_string(skb, NFTA_GEN_PROC_NAME, get_task_comm(buf, current)))