linux - 在 AF_PACKET 套接字上发送数据

Question

如何在 SOCK_PACKET 套接字上发送数据而不指定它绑定到哪个主机？我已经构建了 IP 标头以显示它应该去哪里，但是 write() 不起作用。

Answer 1

Don't. use write(), use sendto().

If you use PF_PACKET,SOCK_DGRAM, then it builds the link-layer headers for you, which is normally what you want. You still need to build whatever higher protocol you are using on top though.

You specify a sockaddr_ll in the destination parameter. You can specify a link-layer unicast address, multicast address or broadcast address.