mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 01:54:09 +08:00
4d5d33a085
This fixes build error regarding redefinition:
CLANG-bpf samples/bpf/parse_varlen.o
samples/bpf/parse_varlen.c:111:8: error: redefinition of 'vlan_hdr'
struct vlan_hdr {
^
./include/linux/if_vlan.h:38:8: note: previous definition is here
So remove duplicate 'struct vlan_hdr' in sample code and include if_vlan.h
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
151 lines
3.4 KiB
C
151 lines
3.4 KiB
C
/* Copyright (c) 2016 Facebook
|
|
*
|
|
* 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 <linux/if_ether.h>
|
|
#include <linux/if_vlan.h>
|
|
#include <linux/ip.h>
|
|
#include <linux/ipv6.h>
|
|
#include <linux/in.h>
|
|
#include <linux/tcp.h>
|
|
#include <linux/udp.h>
|
|
#include <uapi/linux/bpf.h>
|
|
#include <net/ip.h>
|
|
#include "bpf_helpers.h"
|
|
|
|
#define DEFAULT_PKTGEN_UDP_PORT 9
|
|
#define DEBUG 0
|
|
|
|
static int tcp(void *data, uint64_t tp_off, void *data_end)
|
|
{
|
|
struct tcphdr *tcp = data + tp_off;
|
|
|
|
if (tcp + 1 > data_end)
|
|
return 0;
|
|
if (tcp->dest == htons(80) || tcp->source == htons(80))
|
|
return TC_ACT_SHOT;
|
|
return 0;
|
|
}
|
|
|
|
static int udp(void *data, uint64_t tp_off, void *data_end)
|
|
{
|
|
struct udphdr *udp = data + tp_off;
|
|
|
|
if (udp + 1 > data_end)
|
|
return 0;
|
|
if (udp->dest == htons(DEFAULT_PKTGEN_UDP_PORT) ||
|
|
udp->source == htons(DEFAULT_PKTGEN_UDP_PORT)) {
|
|
if (DEBUG) {
|
|
char fmt[] = "udp port 9 indeed\n";
|
|
|
|
bpf_trace_printk(fmt, sizeof(fmt));
|
|
}
|
|
return TC_ACT_SHOT;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int parse_ipv4(void *data, uint64_t nh_off, void *data_end)
|
|
{
|
|
struct iphdr *iph;
|
|
uint64_t ihl_len;
|
|
|
|
iph = data + nh_off;
|
|
if (iph + 1 > data_end)
|
|
return 0;
|
|
|
|
if (ip_is_fragment(iph))
|
|
return 0;
|
|
ihl_len = iph->ihl * 4;
|
|
|
|
if (iph->protocol == IPPROTO_IPIP) {
|
|
iph = data + nh_off + ihl_len;
|
|
if (iph + 1 > data_end)
|
|
return 0;
|
|
ihl_len += iph->ihl * 4;
|
|
}
|
|
|
|
if (iph->protocol == IPPROTO_TCP)
|
|
return tcp(data, nh_off + ihl_len, data_end);
|
|
else if (iph->protocol == IPPROTO_UDP)
|
|
return udp(data, nh_off + ihl_len, data_end);
|
|
return 0;
|
|
}
|
|
|
|
static int parse_ipv6(void *data, uint64_t nh_off, void *data_end)
|
|
{
|
|
struct ipv6hdr *ip6h;
|
|
struct iphdr *iph;
|
|
uint64_t ihl_len = sizeof(struct ipv6hdr);
|
|
uint64_t nexthdr;
|
|
|
|
ip6h = data + nh_off;
|
|
if (ip6h + 1 > data_end)
|
|
return 0;
|
|
|
|
nexthdr = ip6h->nexthdr;
|
|
|
|
if (nexthdr == IPPROTO_IPIP) {
|
|
iph = data + nh_off + ihl_len;
|
|
if (iph + 1 > data_end)
|
|
return 0;
|
|
ihl_len += iph->ihl * 4;
|
|
nexthdr = iph->protocol;
|
|
} else if (nexthdr == IPPROTO_IPV6) {
|
|
ip6h = data + nh_off + ihl_len;
|
|
if (ip6h + 1 > data_end)
|
|
return 0;
|
|
ihl_len += sizeof(struct ipv6hdr);
|
|
nexthdr = ip6h->nexthdr;
|
|
}
|
|
|
|
if (nexthdr == IPPROTO_TCP)
|
|
return tcp(data, nh_off + ihl_len, data_end);
|
|
else if (nexthdr == IPPROTO_UDP)
|
|
return udp(data, nh_off + ihl_len, data_end);
|
|
return 0;
|
|
}
|
|
|
|
SEC("varlen")
|
|
int handle_ingress(struct __sk_buff *skb)
|
|
{
|
|
void *data = (void *)(long)skb->data;
|
|
struct ethhdr *eth = data;
|
|
void *data_end = (void *)(long)skb->data_end;
|
|
uint64_t h_proto, nh_off;
|
|
|
|
nh_off = sizeof(*eth);
|
|
if (data + nh_off > data_end)
|
|
return 0;
|
|
|
|
h_proto = eth->h_proto;
|
|
|
|
if (h_proto == ETH_P_8021Q || h_proto == ETH_P_8021AD) {
|
|
struct vlan_hdr *vhdr;
|
|
|
|
vhdr = data + nh_off;
|
|
nh_off += sizeof(struct vlan_hdr);
|
|
if (data + nh_off > data_end)
|
|
return 0;
|
|
h_proto = vhdr->h_vlan_encapsulated_proto;
|
|
}
|
|
if (h_proto == ETH_P_8021Q || h_proto == ETH_P_8021AD) {
|
|
struct vlan_hdr *vhdr;
|
|
|
|
vhdr = data + nh_off;
|
|
nh_off += sizeof(struct vlan_hdr);
|
|
if (data + nh_off > data_end)
|
|
return 0;
|
|
h_proto = vhdr->h_vlan_encapsulated_proto;
|
|
}
|
|
if (h_proto == htons(ETH_P_IP))
|
|
return parse_ipv4(data, nh_off, data_end);
|
|
else if (h_proto == htons(ETH_P_IPV6))
|
|
return parse_ipv6(data, nh_off, data_end);
|
|
return 0;
|
|
}
|
|
char _license[] SEC("license") = "GPL";
|