mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-27 13:05:03 +08:00
509e56b37c
Since this is not really a device with all capabilities, this test ensures that it has *enough* to make it through the data path without causing unwanted side-effects (read crash!). Signed-off-by: Mahesh Bandewar <maheshb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
101 lines
2.5 KiB
C
101 lines
2.5 KiB
C
// 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 <maheshb@google.com>
|
|
*/
|
|
|
|
#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 <maheshb@google.com>");
|
|
MODULE_LICENSE("GPL");
|