forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
100 lines
2.5 KiB
100 lines
2.5 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* This module tests the blackhole_dev that is created during the |
|
* net subsystem initialization. The test this module performs is |
|
* by injecting an skb into the stack with skb->dev as the |
|
* blackhole_dev and expects kernel to behave in a sane manner |
|
* (in other words, *not crash*)! |
|
* |
|
* Copyright (c) 2018, Mahesh Bandewar <[email protected]> |
|
*/ |
|
|
|
#include <linux/init.h> |
|
#include <linux/module.h> |
|
#include <linux/printk.h> |
|
#include <linux/skbuff.h> |
|
#include <linux/netdevice.h> |
|
#include <linux/udp.h> |
|
#include <linux/ipv6.h> |
|
|
|
#include <net/dst.h> |
|
|
|
#define SKB_SIZE 256 |
|
#define HEAD_SIZE (14+40+8) /* Ether + IPv6 + UDP */ |
|
#define TAIL_SIZE 32 /* random tail-room */ |
|
|
|
#define UDP_PORT 1234 |
|
|
|
static int __init test_blackholedev_init(void) |
|
{ |
|
struct ipv6hdr *ip6h; |
|
struct sk_buff *skb; |
|
struct ethhdr *ethh; |
|
struct udphdr *uh; |
|
int data_len; |
|
int ret; |
|
|
|
skb = alloc_skb(SKB_SIZE, GFP_KERNEL); |
|
if (!skb) |
|
return -ENOMEM; |
|
|
|
/* Reserve head-room for the headers */ |
|
skb_reserve(skb, HEAD_SIZE); |
|
|
|
/* Add data to the skb */ |
|
data_len = SKB_SIZE - (HEAD_SIZE + TAIL_SIZE); |
|
memset(__skb_put(skb, data_len), 0xf, data_len); |
|
|
|
/* Add protocol data */ |
|
/* (Transport) UDP */ |
|
uh = (struct udphdr *)skb_push(skb, sizeof(struct udphdr)); |
|
skb_set_transport_header(skb, 0); |
|
uh->source = uh->dest = htons(UDP_PORT); |
|
uh->len = htons(data_len); |
|
uh->check = 0; |
|
/* (Network) IPv6 */ |
|
ip6h = (struct ipv6hdr *)skb_push(skb, sizeof(struct ipv6hdr)); |
|
skb_set_network_header(skb, 0); |
|
ip6h->hop_limit = 32; |
|
ip6h->payload_len = data_len + sizeof(struct udphdr); |
|
ip6h->nexthdr = IPPROTO_UDP; |
|
ip6h->saddr = in6addr_loopback; |
|
ip6h->daddr = in6addr_loopback; |
|
/* Ether */ |
|
ethh = (struct ethhdr *)skb_push(skb, sizeof(struct ethhdr)); |
|
skb_set_mac_header(skb, 0); |
|
|
|
skb->protocol = htons(ETH_P_IPV6); |
|
skb->pkt_type = PACKET_HOST; |
|
skb->dev = blackhole_netdev; |
|
|
|
/* Now attempt to send the packet */ |
|
ret = dev_queue_xmit(skb); |
|
|
|
switch (ret) { |
|
case NET_XMIT_SUCCESS: |
|
pr_warn("dev_queue_xmit() returned NET_XMIT_SUCCESS\n"); |
|
break; |
|
case NET_XMIT_DROP: |
|
pr_warn("dev_queue_xmit() returned NET_XMIT_DROP\n"); |
|
break; |
|
case NET_XMIT_CN: |
|
pr_warn("dev_queue_xmit() returned NET_XMIT_CN\n"); |
|
break; |
|
default: |
|
pr_err("dev_queue_xmit() returned UNKNOWN(%d)\n", ret); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void __exit test_blackholedev_exit(void) |
|
{ |
|
pr_warn("test_blackholedev module terminating.\n"); |
|
} |
|
|
|
module_init(test_blackholedev_init); |
|
module_exit(test_blackholedev_exit); |
|
|
|
MODULE_AUTHOR("Mahesh Bandewar <[email protected]>"); |
|
MODULE_LICENSE("GPL");
|
|
|