linux-imx

/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com

 *

 * 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.

 */

#include <uapi/linux/bpf.h>

#include "bpf_helpers.h"

#include <uapi/linux/in.h>

#include <uapi/linux/if.h>

#include <uapi/linux/if_ether.h>

#include <uapi/linux/ip.h>

#include <uapi/linux/ipv6.h>

#include <uapi/linux/if_tunnel.h>

#include <uapi/linux/mpls.h>

#define IP_MF       0x2000

#define IP_OFFSET   0x1FFF

​

#define PROG(F) SEC("socket/"__stringify(F)) int bpf_func_##F

​

struct bpf_map_def SEC("maps") jmp_table = {

    .type = BPF_MAP_TYPE_PROG_ARRAY,

    .key_size = sizeof(u32),

    .value_size = sizeof(u32),

    .max_entries = 8,

};

​

#define PARSE_VLAN 1

#define PARSE_MPLS 2

#define PARSE_IP 3

#define PARSE_IPV6 4

​

/* protocol dispatch routine.

 * It tail-calls next BPF program depending on eth proto

 * Note, we could have used:

 * bpf_tail_call(skb, &jmp_table, proto);

 * but it would need large prog_array

 */

static inline void parse_eth_proto(struct __sk_buff *skb, u32 proto)

{

    switch (proto) {

    case ETH_P_8021Q:

    case ETH_P_8021AD:

        bpf_tail_call(skb, &jmp_table, PARSE_VLAN);

        break;

    case ETH_P_MPLS_UC:

    case ETH_P_MPLS_MC:

        bpf_tail_call(skb, &jmp_table, PARSE_MPLS);

        break;

    case ETH_P_IP:

        bpf_tail_call(skb, &jmp_table, PARSE_IP);

        break;

    case ETH_P_IPV6:

        bpf_tail_call(skb, &jmp_table, PARSE_IPV6);

        break;

    }

}

​

struct vlan_hdr {

    __be16 h_vlan_TCI;

    __be16 h_vlan_encapsulated_proto;

};

​

struct flow_key_record {

    __be32 src;

    __be32 dst;

    union {

        __be32 ports;

        __be16 port16[2];

    };

    __u32 ip_proto;

};

​

static inline int ip_is_fragment(struct __sk_buff *ctx, __u64 nhoff)

{

    return load_half(ctx, nhoff + offsetof(struct iphdr, frag_off))

        & (IP_MF | IP_OFFSET);

}

​

static inline __u32 ipv6_addr_hash(struct __sk_buff *ctx, __u64 off)

{

    __u64 w0 = load_word(ctx, off);

    __u64 w1 = load_word(ctx, off + 4);

    __u64 w2 = load_word(ctx, off + 8);

    __u64 w3 = load_word(ctx, off + 12);

​

    return (__u32)(w0 ^ w1 ^ w2 ^ w3);

}

​

struct globals {

    struct flow_key_record flow;

};