Wenn ich ein Raw-Socket-Programm ausgeführt wird, generiert es einen ungültigen Fehler Argumenten

Question

Bitte helfen Sie mir.
Ich finde keine Antworten dafür, nach langer Suche für 2 Tage iam Posting. bitte helfen Sie mir ich sehr neu zu Socket-Programmierung und ich schrieb einen kleinen Code, um Pakete an TCP-Ebene für die ich verwendet ip_queue's und netlinks mit NETLINK_FIREWALL-Protokoll. Was ich getan habe, ist

-I OUTPUT -j QUEUE -p udp --destination-port 19989

ich iptables auf Eingabeaufforderung lief.
mein Code ist (nur um Pakete nicht viel zu empfangen)
nur vermeiden es icmp Fehler bei Remote-und Paketinformation mit ohne zu Anwendungsschicht übergeben.

---

1 #include<asm/types.h> 
2 #include<sys/socket.h> 
3 #include<linux/netlink.h> 
4 #include<linux/netfilter_ipv4/ip_queue.h> 
5 #include<stdio.h> 
6 #include<stdlib.h> 
7 #include<netinet/in.h> 
8 #include<arpa/inet.h> 
9 #include<netdb.h>  
10 #include<linux/ip.h>  
11 #include<linux/icmp.h> 
12 #include<string.h> 
13 #include<unistd.h> 
14 
15 int nl_sock_fd = 0; 
16 struct sockaddr_nl nl_addr; 
17 int seq = 0; 
18 struct ipq_mode_msg* modeMessage; 
19 struct ipq_verdict_msg *ver_data = NULL; 
20 struct nlmsghdr* netlinkHeader =NULL; 
21 struct ipq_packet_msg* packet = NULL; 
22 char buf1[128] ={0}; 
23 char buf[4096] = {0}; 
24 char buf2[8192] = {0}; 
25 
26 int addrSize; 
27 int len,i; 
28 
29 
30 int main(int argc, char *argv[]) 
31 { 
32 int iter= 0; 
33 
34 /******* create and set the values for netlink sockets*************/ 
35 if((nl_sock_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_FIREWALL))<0) 
36 { 
37 printf("socket creation failed!\n"); 
38 return ; 
39 } 
40 printf("socket fd =%d\n", nl_sock_fd); 
41 
42 // Set up the kernels address structure: 
43 memset(&nl_addr, 0, sizeof(struct sockaddr_nl));  
44 nl_addr.nl_family = AF_NETLINK;  
45 nl_addr.nl_pid = 0; // The with address 0 in netlink /getpid();  
46 nl_addr.nl_groups = 0; // we dont need any multicast groups 
47 nl_addr.nl_pad = 0; 
48 if(bind(nl_sock_fd, (struct sockaddr*)&nl_addr, sizeof(nl_addr))<0) 
49 { 
50 printf("bind failed"); 
51 } 
52 /******************* set mode values ***************************/ 
53 memset(buf1, 0, 128); 
54 netlinkHeader = (struct nlmsghdr*)buf1; 
55 netlinkHeader->nlmsg_len = NLMSG_LENGTH(sizeof(struct ipq_mode_msg)); 
56 //NLMSG_LENGTH size of the ancilliary data 
57 netlinkHeader->nlmsg_type = IPQM_MODE; //IPQM Packet 
58 netlinkHeader->nlmsg_flags = NLM_F_REQUEST; //request message 
59 netlinkHeader->nlmsg_seq = seq++; //to allow response correlation 
60 netlinkHeader->nlmsg_pid = getpid(); 
61 
62 // modeMessage=(struct ipq_mode_msg*)NLMSG_DATA(netlinkHeader); 
63 modeMessage=NLMSG_DATA(netlinkHeader); 
64 //NLMSG_DATA returns a pointer to the ancilliary data which it contains 
65 modeMessage->value = IPQ_COPY_PACKET; //copy metadata and range 0 is entire packet 
66 modeMessage->range = 0; // copy the entire payload 
67 
68 if(sendto(nl_sock_fd, (void*)buf1, netlinkHeader->nlmsg_len, 0, (struct sockaddr*)&nl_addr, s izeof(struct sockaddr_nl)) < 0) 
69 { 
70 printf("unable to set netlink mode ...\n"); 
71 exit(0); 
72 } 
73 printf("portion of data sent to netlink\n"); 
74 for(iter = 0; iter < 24; iter++) 
75 { 
76 printf(" %x",(unsigned int)buf1[iter]); 
77 if(!(iter%10) && iter !=0) 
78 printf("\n"); 
79 } 
80 printf("\n"); 
81 
82 /*********** receiving msg ******************/ 
83 printf("socket is up and waiting for messages....\n"); 
84 
85 while(1) 
86 { 
87 //struct nlmsghdr* netlinkHeader = buf1; 
88 
89 //netlinkHeader = buf1; 
90 printf(" iam at recvfrom \n"); 
91 len = recvfrom(nl_sock_fd, buf2, NLMSG_LENGTH(sizeof(struct ipq_packet_msg)), 0, (struct soc kaddr*)&nl_addr, &addrSize); 
92 printf(" NLMSG_LENGTH = %d\n",NLMSG_LENGTH(sizeof(struct ipq_packet_msg))); 
93 if(len < 0) 
94 { 
95 printf("unable to recive packet from the kernel\n"); 
96 return 0; 
97 } 
98 
99 netlinkHeader = (struct nlmsghdr*) buf2; 
100 
101 printf("message received with pid=%d \n", nl_addr.nl_pid); 
102 
103 if(netlinkHeader->nlmsg_type == NLMSG_ERROR) 
104 { 
105 struct nlmsgerr* pError = (struct nlmsgerr*)NLMSG_DATA(netlinkHeader); 
106 if(pError->error != 0) // Error number 0 is an acknowledgement not an error. 
107 { 
108 printf("error occured while receiving the message from the kernel.\n"); 
109 printf("error code %d \n ", pError->error); 
110 printf("\n****** %s ********\n",strerror(-1 * pError->error));  
111 printf("msg->nlmsg_len %d\n", pError->msg.nlmsg_len); 
112 printf("msg->nlmsg_type %x\n", pError->msg.nlmsg_type); 
113 printf("msg->nlmsg_flags %x\n",pError->msg.nlmsg_flags); 
114 printf("msg->nlmsg_seq: %d\n", pError->msg.nlmsg_seq); 
115 printf("msg->nlmsg_pid: %d\n", pError->msg.nlmsg_pid); 
116 return 0; 
117 } 
118 } 
119 else 
120 { 
121 
122 printf("Message from kernel:\n "); 
123 printf("Packet ID: %d\n",packet->packet_id); 
124 printf("Payload size:%d\n", packet->data_len); 
125 for(i = 0; i < packet->data_len; ++i) 
126 { 
127 printf("%c ", packet->payload[ i ]); 
128 } 
129 printf("\n"); 
130 
131 } 
132 printf("\n dumping packets over \n"); 
133 netlinkHeader=(struct nlmsghdr *)buf1; 
134 packet=NLMSG_DATA(netlinkHeader); 
135 /*for the example just forward all packets*/ 
136 //netlinkHeader = (struct nlmsghdr*)buf2; 
137 netlinkHeader->nlmsg_type=IPQM_VERDICT; 
138 netlinkHeader->nlmsg_len=NLMSG_LENGTH(sizeof(struct ipq_verdict_msg)); 
139 netlinkHeader->nlmsg_flags=(NLM_F_REQUEST);/*this is a request, don’t ask for an answer*/ 
140 netlinkHeader->nlmsg_pid=getpid(); 
141 netlinkHeader->nlmsg_seq=seq++;/*arbitrary unique value to allow response correlation*/ 
142 ver_data=(struct ipq_verdict_msg *)NLMSG_DATA(netlinkHeader); 
143 
144 //ver_data->value=NF_ACCEPT; 
145 //ver_data->value=NF_QUEUE; 
146 ver_data->id=packet->packet_id; 
147 if(sendto(nl_sock_fd,(void *)netlinkHeader,netlinkHeader->nlmsg_len,0, 
148 (struct sockaddr *)&nl_addr,sizeof(struct sockaddr_nl)) < 0) 
149 { 
150 perror("unable to send mode message"); 
151 exit(0); 
152 } 
153 
154 
155 } 
156 
157 return 0; 
158 } 

Ausgang kommt wie

socket fd =3 
portion of data sent to netlink 
18 0 0 0 11 0 1 0 0 0 0 
0 38 30 0 0 2 0 0 0 0 
0 0 0 
socket is up and waiting for messages.... 
iam at recvfrom 
NLMSG_LENGTH = 88 
message received with pid=0 
error occured while receiving the message from the kernel. 
error code -22 



****** Invalid argument ******** 
msg->nlmsg_len 24 
msg->nlmsg_type 11 
msg->nlmsg_flags 1 
msg->nlmsg_seq: 0 
msg->nlmsg_pid: 12344 

mir bitte helfen
und einige besten Bücher geben, die Raw Sockets

Answer 1

This und this lernen helfen könnten Sie ein wenig helfen.

Um einen beschreibenden Fehlercode zu erhalten, geben Sie man recv ein oder suchen Sie in errno.h. Wenn Sie die Funktion perror() verwenden, wird eine Zeichenfolge mit einer Fehlerbeschreibung ausgedruckt.