net/ipv4/ip_options.c

70  * build in dopt compiled option set appropriate for answering.
74  * NOTE: dopt cannot point to skb.
77 int __ip_options_echo(struct net *net, struct ip_options *dopt,
84 	memset(dopt, 0, sizeof(struct ip_options));
90 	dptr = dopt->__data;
95 		dopt->rr = dopt->optlen + sizeof(struct iphdr);
101 			dopt->rr_needaddr = 1;
104 		dopt->optlen += optlen;
109 		dopt->ts = dopt->optlen + sizeof(struct iphdr);
115 				dopt->ts_needaddr = 1;
122 					dopt->ts_needtime = 1;
125 					dopt->ts_needtime = 0;
132 							dopt->ts_needtime = 1;
141 		dopt->optlen += optlen;
165 			dopt->faddr = faddr;
170 			dopt->srr = dopt->optlen + sizeof(struct iphdr);
171 			dopt->optlen += doffset+3;
172 			dopt->is_strictroute = sopt->is_strictroute;
177 		dopt->cipso = dopt->optlen+sizeof(struct iphdr);
180 		dopt->optlen += optlen;
182 	while (dopt->optlen & 3) {
184 		dopt->optlen++;