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Diffstat (limited to 'src/ebpf/xdp_drop_ebpf.c')
-rw-r--r--src/ebpf/xdp_drop_ebpf.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/src/ebpf/xdp_drop_ebpf.c b/src/ebpf/xdp_drop_ebpf.c
deleted file mode 100644
index a08edf58d..000000000
--- a/src/ebpf/xdp_drop_ebpf.c
+++ /dev/null
@@ -1,97 +0,0 @@
-#include <linux/bpf.h>
-#include <linux/if_ether.h>
-#include <linux/in.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-#include <linux/udp.h>
-
-#include <stdint.h>
-
-/* IP flags. */
-#define IP_CE 0x8000 /* Flag: "Congestion" */
-#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
-#define IP_MF 0x2000 /* Flag: "More Fragments" */
-#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
-
-#define SEC(NAME) __attribute__((section(NAME), used))
-
-#define htons(x) ((__be16)___constant_swab16((x)))
-#define htonl(x) ((__be32)___constant_swab32((x)))
-
-struct vlan_hdr {
- __be16 h_vlan_TCI;
- __be16 h_vlan_encapsulated_proto;
-};
-
-SEC("prog")
-int xdp_drop(struct xdp_md *ctx) {
- void *data_end = (void *)(long)ctx->data_end;
- void *data = (void *)(long)ctx->data;
- struct ethhdr *eth = data;
-
- uint64_t nh_off = sizeof(*eth);
- if (data + nh_off > data_end) {
- return XDP_PASS;
- }
-
- uint16_t h_proto = eth->h_proto;
- int i;
-
- /* Handle double VLAN tagged packet. See https://en.wikipedia.org/wiki/IEEE_802.1ad */
- for (i = 0; i < 2; i++) {
- if (h_proto == htons(ETH_P_8021Q) || h_proto == htons(ETH_P_8021AD)) {
- struct vlan_hdr *vhdr;
-
- vhdr = data + nh_off;
- nh_off += sizeof(struct vlan_hdr);
- if (data + nh_off > data_end) {
- return XDP_PASS;
- }
- h_proto = vhdr->h_vlan_encapsulated_proto;
- }
- }
-
- if (h_proto == htons(ETH_P_IP)) {
- struct iphdr *iph = data + nh_off;
- struct udphdr *udph = data + nh_off + sizeof(struct iphdr);
-
- uint32_t hostid = iph->daddr >> 24;
-
- if (udph + 1 > (struct udphdr *)data_end) {
- return XDP_PASS;
- }
- if (hostid == 0 || hostid == 255) {
- return XDP_DROP;
- }
- if (iph->frag_off & htons(IP_MF | IP_OFFSET)) {
- return XDP_DROP;
- }
- if (iph->protocol == IPPROTO_UDP) {
- __be16 dport = htons(udph->dest);
- __be16 sport = htons(udph->source);
-
- if (dport == 53 || sport == 53) {
- return XDP_DROP;
- }
- }
- } else if (h_proto == htons(ETH_P_IPV6)) {
- struct ipv6hdr *ip6h = data + nh_off;
- struct udphdr *udph = data + nh_off + sizeof(struct ipv6hdr);
-
- if (udph + 1 > (struct udphdr *)data_end) {
- return XDP_PASS;
- }
- if (ip6h->nexthdr == IPPROTO_UDP) {
- __be16 dport = htons(udph->dest);
- __be16 sport = htons(udph->source);
-
- if (dport == 53 || sport == 53) {
- return XDP_DROP;
- }
- }
- }
-
- return XDP_PASS;
-}
-
-char _license[] SEC("license") = "GPL";