我的虛擬接口通過(guò)netif_rx傳包，上層協(xié)議似乎收不到

pqy330

1. #include <linux/module.h>
   
2. #include <linux/init.h>
   
3. #include <linux/device.h>
   
4. #include <linux/string.h>
   
5. #include <linux/slab.h>
   
6. #include <linux/module.h>
   
7. #include <linux/netdevice.h>
   
8. #include <linux/kernel.h>
   
9. #include <linux/etherdevice.h>
   
10. 
    
11. struct net_device *virtualNIC;
    
12. 
    
13. int virtualNIC_open(struct net_device *dev) {
    
14. printk("virtualNIC_open called\n");
    
15. return 0;
    
16. }
    
17. 
    
18. int virtualNIC_release(struct net_device *dev) {
    
19. printk("virtualNIC_release called\n");
    
20. netif_stop_queue(dev);
    
21. return 0;
    
22. }
    
23. 
    
24. int virtualNIC_xmit(struct sk_buff *skb, struct net_device *dev) {
    
25. printk("dummy xmit function called...\n");
    
26. dev_kfree_skb(skb);
    
27. return 0;
    
28. }
    
29. 
    
30. 
    
31. int virtualNIC_init(struct net_device *dev) {
    
32.   printk("virtualNIC device initialized\n");
    
33.   return 0;
    
34. };
    
35. const struct net_device_ops my_netdev_ops = {
    
36.      .ndo_init = virtualNIC_init,
    
37.      .ndo_open = virtualNIC_open,
    
38.      .ndo_stop = virtualNIC_release,
    
39.      .ndo_start_xmit = virtualNIC_xmit,
    
40. };
    
41. 
    
42. //static void ether_setup(struct net_device *dev){
    
43. //  dev->netdev_ops = &my_netdev_ops;
    
44. //}
    
45. 
    
46. 
    
47. int virtualNIC_init_module(void) {
    
48. int result;
    
49. char mac[6] = {0x12,0x34,0x56,0x78,0x90,0xab};
    
50. virtualNIC = alloc_etherdev(0);
    
51. if(!virtualNIC){
    
52.      return -1;
    
53. }
    
54. virtualNIC->netdev_ops = &my_netdev_ops;
    
55. 
    
56. memcpy(virtualNIC->dev_addr, mac, virtualNIC->addr_len);
    
57. if((result = register_netdev(virtualNIC))) {
    
58.   printk("virtualNIC: Error %d initalizing card ...", result);
    
59.   return result;
    
60. }
    
61. return 0;
    
62. }
    
63. 
    
64. 
    
65. static ssize_t vnet_recv(struct class *cls, struct class_attribute *attr, const char *_buf, size_t _count)
    
66. {
    
67.     struct sk_buff *skb = dev_alloc_skb(_count+2);
    
68.     if(!skb){
    
69.         printk("Out of mem!\n");
    
70.         goto out;
    
71.     }
    
72.     skb_reserve(skb, 2);
    
73.     memcpy(skb_put(skb, _count), _buf, _count);
    
74.     skb->dev = virtualNIC;
    
75.     skb->protocol = eth_type_trans(skb, virtualNIC);
    
76.     skb->ip_summed = CHECKSUM_UNNECESSARY;
    
77.     //skb->pkt_type = PACKET_HOST;
    
78.    
    
79.     printk("%d %d %d\n",skb->pkt_type, ntohs(skb->protocol), netif_rx_ni(skb));
    
80. out:   
    
81.     return _count;
    
82. }
    
83. 
    
84. static struct class *vnet_class = NULL;
    
85. static CLASS_ATTR(recv, 0220, NULL, vnet_recv);
    
86. int __init vnet_init (void)
    
87. {
    
88.     virtualNIC_init_module();
    
89.     vnet_class = class_create(THIS_MODULE, "vnet");
    
90.      if (IS_ERR(vnet_class))
    
91.     {   
    
92.         printk("Create class vnet_class failed.\n");
    
93.         return -ENOMEM;
    
94.     }
    
95.     class_create_file(vnet_class, &class_attr_recv);
    
96.     return 0;
    
97. }
    
98. 
    
99. void __exit
    
100. vnet_exit (void)
     
101. {
     
102.   class_remove_file(vnet_class, &class_attr_recv);
     
103.   class_destroy(vnet_class);
     
104.   unregister_netdev(virtualNIC);
     
105.   free_netdev(virtualNIC);
     
106.   vnet_class = NULL;
     
107. }
     
108. 
     
109. module_init (vnet_init);
     
110. module_exit (vnet_exit);
     
111. 
     
112. 
     
113. MODULE_AUTHOR("None");
     
114. MODULE_LICENSE ("GPL");
     

復(fù)制代碼

我注冊(cè)了個(gè)netdev, 以及sys一個(gè)入口文件，應(yīng)用層負(fù)責(zé)構(gòu)建完整的以太網(wǎng)幀寫(xiě)到入口文件，然后模塊把這個(gè)以太網(wǎng)幀傳給內(nèi)核。wireshark抓包看包很正常，各項(xiàng)參數(shù)都對(duì)，目的mac是我的虛擬接口的，ip checksum，udp checksum都對(duì)，但是應(yīng)用層的udp socket收不到。netif_rx返回0.  求大佬指教哪里有問(wèn)題。

pqy330

用gdb跟蹤到問(wèn)題了，dest ip 不能是127.0.0.1, 否則被丟掉