当我尝试发送原始以太网数据包时,我的代码中的 sendto 函数出现问题。
我使用的是 Ubuntu 12.04.01 LTS,通过两个 vde_switches 和一个 dpipe 连接了两个 Tap 设备
例子:
我的发送程序创建如下所示的数据包,程序由来自tap0的套接字绑定并将数据包发送到tap1。在 tap1 上,一个接收器等待套接字上的所有数据包。
我的原始以太网数据包看起来是这样的:
目的地地址__ __ _源地址_ _ __ _ ___ 类型/长度__ _数据
00:00:01:00:00:00 _ __ 00:00:01:00:00:01 _ ___字节长度_一些数据
要发送的示例数据包:
00:00:01:00:00:00 00:00:01:00:00:01 (length in byte) (Message)test
但是当我查看wireshark时,我的程序会生成两个数据包:
第一个数据包是 IPX 数据包和 [Malformed Packet],看起来像十六进制(数据 = 测试)
00 04 00 01 00 06 00 00 01 00 00 01 00 00 00 01 74 65 73 74 00
Linux cooked capture
Packet type: sent by us (4)
Link-layer address type: 1
Link-layer address length: 6
Source: 00:00:01:00:00:01
Protocol: Raw 802.3 (0x0001)
[Malformed Packet: IPX]
第二个数据包未知协议
00 00 00 01 00 06 00 00 01 00 00 01 00 00 31 00 74 65 73 74 00
Linux cooked capture
Packet type: Unicast to us (0)
Link-layer address type: 1
Link-layer address length: 6
Source: 00:00:01:00:00:01
Protocol: Unknown (0x3100)
Data
Data: 7465737400
[Length: 5]
从我的源代码中删除
sock_desc = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
/*struct for sending*/
sock_addr.sll_family = AF_PACKET;
sock_addr.sll_protocol = htons(ETH_P_802_3);
sock_addr.sll_ifindex = if_nametoindex(argv[1]);
sock_addr.sll_hatype = ARPHRD_ETHER; //Ethernet 10Mbps
sock_addr.sll_pkttype = PACKET_HOST; // Paket zu irgendjemand
sock_addr.sll_halen = ETH_ALEN; //6 Oktets in einer ethernet addr
/*MAC Length 8 Oktets*/
sock_addr.sll_addr[0] = frame.src_mac[0];
sock_addr.sll_addr[1] = frame.src_mac[1];
sock_addr.sll_addr[2] = frame.src_mac[2];
sock_addr.sll_addr[3] = frame.src_mac[3];
sock_addr.sll_addr[4] = frame.src_mac[4];
sock_addr.sll_addr[5] = frame.src_mac[5];
/*not in use*/
sock_addr.sll_addr[6] = 0x00;
sock_addr.sll_addr[7] = 0x00;
memset(buffer, '0', sizeof(char)*ETH_FRAME_LEN);
/*set the frame header*/
/*build RAW Ethernet packet*/
buffer[0] = frame.dest_mac[0];
buffer[1] = frame.dest_mac[1];
buffer[2] = frame.dest_mac[2];
buffer[3] = frame.dest_mac[3];
buffer[4] = frame.dest_mac[4];
buffer[5] = frame.dest_mac[5];
buffer[6] = frame.src_mac[0];
buffer[7] = frame.src_mac[1];
buffer[8] = frame.src_mac[2];
buffer[9] = frame.src_mac[3];
buffer[10] = frame.src_mac[4];
buffer[11] = frame.src_mac[5];
while(frame.data[0] != '*'){
printf("Input: ");
scanf("%s", frame.data);
tempLength = 0;
while(frame.data[tempLength] != '\0'){
tempLength++;
}
input = 0;
for(sendLen = 14;sendLen <= (14+tempLength);sendLen++){
buffer[sendLen] = frame.data[input];
input++;
}
sprintf(convLen,"%x", (14 + input));
buffer[12] = convLen[0];
buffer[13] = convLen[1];
length_in_byte = sendto(sock_desc, buffer, 14+input,0,(struct sockaddr*) &sock_addr,sizeof(struct sockaddr_ll));
if(length_in_byte <= 0){
printf("Error beim Senden");
}else{
printf("\n");
printf("src: %02x:%02x:%02x:%02x:%02x:%02x\t->\tdest: %02x:%02x:%02x:%02x:%02x:%02x\n",frame.src_mac[0],frame.src_mac[1],frame.src_mac[2],frame.src_mac[3],frame.src_mac[4],frame.src_mac[5],frame.dest_mac[0],frame.dest_mac[1],frame.dest_mac[2],frame.dest_mac[3],frame.dest_mac[4],frame.dest_mac[5]);
printf("Data: %s\n", frame.data);
}
}
请我需要一些帮助来找出我的错误。
谢谢转发。