Initial commitmain

Signed-off-by: Toni Uhlig <matzeton@googlemail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/xdp_manip.h b/xdp_manip.h
new file mode 100644
index 0000000..70eba28
--- /dev/null
+++ b/xdp_manip.h
@@ -0,0 +1,28 @@
+#ifndef XDP_MANIP_H
+#define XDP_MANIP_H 1
+
+#include <linux/if_ether.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+
+static __always_inline void swap_eth_addr(struct ethhdr *const ethhdr) {
+  unsigned char src_eth[ETH_ALEN];
+
+  __builtin_memcpy(src_eth, ethhdr->h_source, sizeof(ethhdr->h_source));
+  __builtin_memcpy(ethhdr->h_source, ethhdr->h_dest, sizeof(ethhdr->h_source));
+  __builtin_memcpy(ethhdr->h_dest, src_eth, sizeof(src_eth));
+}
+
+static __always_inline void swap_ip4_addr(struct iphdr *const iphdr) {
+  __be32 src_ip = iphdr->saddr;
+  iphdr->saddr = iphdr->daddr;
+  iphdr->daddr = src_ip;
+}
+
+static __always_inline void swap_udp_port(struct udphdr *const udphdr) {
+  __be16 src_port = udphdr->source;
+  udphdr->source = udphdr->dest;
+  udphdr->dest = src_port;
+}
+
+#endif