ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/samples/bpf/xdp_router_ipv4_kern.c b/marvell/linux/samples/bpf/xdp_router_ipv4_kern.c
new file mode 100644
index 0000000..bf11efc
--- /dev/null
+++ b/marvell/linux/samples/bpf/xdp_router_ipv4_kern.c
@@ -0,0 +1,186 @@
+/* Copyright (C) 2017 Cavium, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ */
+#define KBUILD_MODNAME "foo"
+#include <uapi/linux/bpf.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include "bpf_helpers.h"
+#include <linux/slab.h>
+#include <net/ip_fib.h>
+
+struct trie_value {
+ __u8 prefix[4];
+ __be64 value;
+ int ifindex;
+ int metric;
+ __be32 gw;
+};
+
+/* Key for lpm_trie*/
+union key_4 {
+ u32 b32[2];
+ u8 b8[8];
+};
+
+struct arp_entry {
+ __be64 mac;
+ __be32 dst;
+};
+
+struct direct_map {
+ struct arp_entry arp;
+ int ifindex;
+ __be64 mac;
+};
+
+/* Map for trie implementation*/
+struct {
+ __uint(type, BPF_MAP_TYPE_LPM_TRIE);
+ __uint(key_size, 8);
+ __uint(value_size, sizeof(struct trie_value));
+ __uint(max_entries, 50);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+} lpm_map SEC(".maps");
+
+/* Map for counter*/
+struct {
+ __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
+ __type(key, u32);
+ __type(value, u64);
+ __uint(max_entries, 256);
+} rxcnt SEC(".maps");
+
+/* Map for ARP table*/
+struct {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __type(key, __be32);
+ __type(value, __be64);
+ __uint(max_entries, 50);
+} arp_table SEC(".maps");
+
+/* Map to keep the exact match entries in the route table*/
+struct {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __type(key, __be32);
+ __type(value, struct direct_map);
+ __uint(max_entries, 50);
+} exact_match SEC(".maps");
+
+struct {
+ __uint(type, BPF_MAP_TYPE_DEVMAP);
+ __uint(key_size, sizeof(int));
+ __uint(value_size, sizeof(int));
+ __uint(max_entries, 100);
+} tx_port SEC(".maps");
+
+/* Function to set source and destination mac of the packet */
+static inline void set_src_dst_mac(void *data, void *src, void *dst)
+{
+ unsigned short *source = src;
+ unsigned short *dest = dst;
+ unsigned short *p = data;
+
+ __builtin_memcpy(p, dest, 6);
+ __builtin_memcpy(p + 3, source, 6);
+}
+
+/* Parse IPV4 packet to get SRC, DST IP and protocol */
+static inline int parse_ipv4(void *data, u64 nh_off, void *data_end,
+ __be32 *src, __be32 *dest)
+{
+ struct iphdr *iph = data + nh_off;
+
+ if (iph + 1 > data_end)
+ return 0;
+ *src = iph->saddr;
+ *dest = iph->daddr;
+ return iph->protocol;
+}
+
+SEC("xdp_router_ipv4")
+int xdp_router_ipv4_prog(struct xdp_md *ctx)
+{
+ void *data_end = (void *)(long)ctx->data_end;
+ __be64 *dest_mac = NULL, *src_mac = NULL;
+ void *data = (void *)(long)ctx->data;
+ struct trie_value *prefix_value;
+ int rc = XDP_DROP, forward_to;
+ struct ethhdr *eth = data;
+ union key_4 key4;
+ long *value;
+ u16 h_proto;
+ u32 ipproto;
+ u64 nh_off;
+
+ nh_off = sizeof(*eth);
+ if (data + nh_off > data_end)
+ return rc;
+
+ h_proto = eth->h_proto;
+
+ 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 rc;
+ h_proto = vhdr->h_vlan_encapsulated_proto;
+ }
+ if (h_proto == htons(ETH_P_ARP)) {
+ return XDP_PASS;
+ } else if (h_proto == htons(ETH_P_IP)) {
+ struct direct_map *direct_entry;
+ __be32 src_ip = 0, dest_ip = 0;
+
+ ipproto = parse_ipv4(data, nh_off, data_end, &src_ip, &dest_ip);
+ direct_entry = bpf_map_lookup_elem(&exact_match, &dest_ip);
+ /* Check for exact match, this would give a faster lookup*/
+ if (direct_entry && direct_entry->mac && direct_entry->arp.mac) {
+ src_mac = &direct_entry->mac;
+ dest_mac = &direct_entry->arp.mac;
+ forward_to = direct_entry->ifindex;
+ } else {
+ /* Look up in the trie for lpm*/
+ key4.b32[0] = 32;
+ key4.b8[4] = dest_ip & 0xff;
+ key4.b8[5] = (dest_ip >> 8) & 0xff;
+ key4.b8[6] = (dest_ip >> 16) & 0xff;
+ key4.b8[7] = (dest_ip >> 24) & 0xff;
+ prefix_value = bpf_map_lookup_elem(&lpm_map, &key4);
+ if (!prefix_value)
+ return XDP_DROP;
+ src_mac = &prefix_value->value;
+ if (!src_mac)
+ return XDP_DROP;
+ dest_mac = bpf_map_lookup_elem(&arp_table, &dest_ip);
+ if (!dest_mac) {
+ if (!prefix_value->gw)
+ return XDP_DROP;
+ dest_ip = prefix_value->gw;
+ dest_mac = bpf_map_lookup_elem(&arp_table, &dest_ip);
+ }
+ forward_to = prefix_value->ifindex;
+ }
+ } else {
+ ipproto = 0;
+ }
+ if (src_mac && dest_mac) {
+ set_src_dst_mac(data, src_mac, dest_mac);
+ value = bpf_map_lookup_elem(&rxcnt, &ipproto);
+ if (value)
+ *value += 1;
+ return bpf_redirect_map(&tx_port, forward_to, 0);
+ }
+ return rc;
+}
+
+char _license[] SEC("license") = "GPL";