udhcp: add a few comments, no code changes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2022-12-15 13:34:52 +01:00
parent 242d056230
commit 6c2ddf808e
2 changed files with 11 additions and 0 deletions

View File

@ -80,12 +80,22 @@ int FAST_FUNC d6_send_raw_packet_from_client_data_ifindex(
dest_sll.sll_halen = 6;
memcpy(dest_sll.sll_addr, dest_arp, 6);
//TODO: is bind() necessary? we sendto() to this destination, should work anyway
if (bind(fd, (struct sockaddr *)&dest_sll, sizeof(dest_sll)) < 0) {
msg = "bind(%s)";
goto ret_close;
}
packet.ip6.ip6_vfc = (6 << 4); /* 4 bits version, top 4 bits of tclass */
// In case we have no IPv6 on our interface at all, we can try
// to fill "all hosts" mcast address as source:
// /* FF02::1 is Link-local "All_Nodes" address */
// packet.ip6.ip6_dst.s6_addr[0] = 0xff;
// packet.ip6.ip6_dst.s6_addr[1] = 0x02;
// packet.ip6.ip6_dst.s6_addr[15] = 0x01;
// Maybe some servers will be able to respond to us this way?
// Users report that leaving ::0 address there makes servers try to reply to ::0,
// which doesn't work.
if (src_ipv6)
packet.ip6.ip6_src = *src_ipv6; /* struct copy */
packet.ip6.ip6_dst = *dst_ipv6; /* struct copy */

View File

@ -133,6 +133,7 @@ int FAST_FUNC udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt,
dest_sll.sll_halen = 6;
memcpy(dest_sll.sll_addr, dest_arp, 6);
//TODO: is bind() necessary? we sendto() to this destination, should work anyway
if (bind(fd, (struct sockaddr *)&dest_sll, sizeof(dest_sll)) < 0) {
msg = "bind(%s)";
goto ret_close;