sbin/dhclient/bpf.c

3 /* BPF socket interface code, originally contributed by Archie Cobbs. */
63  * Called by get_interface_list for each interface that's discovered.
64  * Opens a packet filter for each interface and adds it to the select
86 	/* Set the BPF device to point at this interface. */
88 		error("Can't attach interface %s to bpf device %s: %m",
142 	/* Open a BPF device and hang it on this interface... */
225 	/* Open a BPF device and hang it on this interface... */
309 send_packet_priv(struct interface_info *interface, struct imsg_hdr *hdr, int fd)
334 		assemble_hw_header(interface, buf, &bufp);
345 		result = writev(interface->wfdesc, iov, 2);
359 		result = sendmsg(interface->ufdesc, &msg, 0);
367 receive_packet(struct interface_info *interface, unsigned char *buf,
377 	 * interface.  Sigh.
385 		if (interface->rbuf_offset >= interface->rbuf_len) {
386 			length = read(interface->rfdesc, interface->rbuf,
387 			    interface->rbuf_max);
390 			interface->rbuf_offset = 0;
391 			interface->rbuf_len = length;
399 		if (interface->rbuf_len - interface->rbuf_offset <
401 			interface->rbuf_offset = interface->rbuf_len;
406 		memcpy(&hdr, &interface->rbuf[interface->rbuf_offset],
413 		if (interface->rbuf_offset + hdr.bh_hdrlen + hdr.bh_caplen >
414 		    interface->rbuf_len) {
415 			interface->rbuf_offset = interface->rbuf_len;
420 		interface->rbuf_offset += hdr.bh_hdrlen;
428 			interface->rbuf_offset =
429 			    BPF_WORDALIGN(interface->rbuf_offset +
435 		offset = decode_hw_header(interface->rbuf,
436 		    interface->rbuf_offset, hfrom);
444 			interface->rbuf_offset =
445 			    BPF_WORDALIGN(interface->rbuf_offset +
449 		interface->rbuf_offset += offset;
453 		offset = decode_udp_ip_header(interface->rbuf,
454 		    interface->rbuf_offset, from, NULL, hdr.bh_caplen);
458 			interface->rbuf_offset =
459 			    BPF_WORDALIGN(interface->rbuf_offset +
463 		interface->rbuf_offset += offset;
472 			interface->rbuf_offset =
473 			    BPF_WORDALIGN(interface->rbuf_offset +
479 		memcpy(buf, interface->rbuf + interface->rbuf_offset,
481 		interface->rbuf_offset =
482 		    BPF_WORDALIGN(interface->rbuf_offset +