1 files changed, 89 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_tables_ipv4.h b/include/net/netfilter/nf_tables_ipv4.h
new file mode 100644
index 000000000..1f7bea39a
--- /dev/null
+++ b/include/net/netfilter/nf_tables_ipv4.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NF_TABLES_IPV4_H_
+#define _NF_TABLES_IPV4_H_
+
+#include <net/netfilter/nf_tables.h>
+#include <net/ip.h>
+
+static inline void nft_set_pktinfo_ipv4(struct nft_pktinfo *pkt,
+					struct sk_buff *skb)
+{
+	struct iphdr *ip;
+
+	ip = ip_hdr(pkt->skb);
+	pkt->tprot_set = true;
+	pkt->tprot = ip->protocol;
+	pkt->xt.thoff = ip_hdrlen(pkt->skb);
+	pkt->xt.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
+}
+
+static inline int __nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt,
+						  struct sk_buff *skb)
+{
+	struct iphdr *iph, _iph;
+	u32 len, thoff;
+
+	iph = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*iph),
+				 &_iph);
+	if (!iph)
+		return -1;
+
+	if (iph->ihl < 5 || iph->version != 4)
+		return -1;
+
+	len = ntohs(iph->tot_len);
+	thoff = iph->ihl * 4;
+	if (skb->len < len)
+		return -1;
+	else if (len < thoff)
+		return -1;
+
+	pkt->tprot_set = true;
+	pkt->tprot = iph->protocol;
+	pkt->xt.thoff = thoff;
+	pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET;
+
+	return 0;
+}
+
+static inline void nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt,
+						 struct sk_buff *skb)
+{
+	if (__nft_set_pktinfo_ipv4_validate(pkt, skb) < 0)
+		nft_set_pktinfo_unspec(pkt, skb);
+}
+
+static inline int nft_set_pktinfo_ipv4_ingress(struct nft_pktinfo *pkt,
+					       struct sk_buff *skb)
+{
+	struct iphdr *iph;
+	u32 len, thoff;
+
+	if (!pskb_may_pull(skb, sizeof(*iph)))
+		return -1;
+
+	iph = ip_hdr(skb);
+	if (iph->ihl < 5 || iph->version != 4)
+		goto inhdr_error;
+
+	len = ntohs(iph->tot_len);
+	thoff = iph->ihl * 4;
+	if (skb->len < len) {
+		__IP_INC_STATS(nft_net(pkt), IPSTATS_MIB_INTRUNCATEDPKTS);
+		return -1;
+	} else if (len < thoff) {
+		goto inhdr_error;
+	}
+
+	pkt->tprot_set = true;
+	pkt->tprot = iph->protocol;
+	pkt->xt.thoff = thoff;
+	pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET;
+
+	return 0;
+
+inhdr_error:
+	__IP_INC_STATS(nft_net(pkt), IPSTATS_MIB_INHDRERRORS);
+	return -1;
+}
+#endif