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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 /*
     22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
     23  * Use is subject to license terms.
     24  *
     25  * INFORM_SENT state of the client state machine.
     26  */
     27 
     28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
     29 
     30 #include <sys/types.h>
     31 #include <time.h>
     32 #include <sys/socket.h>
     33 #include <netinet/in.h>
     34 #include <netinet/udp.h>
     35 #include <netinet/ip_var.h>
     36 #include <netinet/udp_var.h>
     37 #include <dhcpmsg.h>
     38 
     39 #include "agent.h"
     40 #include "states.h"
     41 #include "interface.h"
     42 #include "packet.h"
     43 
     44 static boolean_t stop_informing(dhcp_smach_t *, unsigned int);
     45 
     46 /*
     47  * dhcp_inform(): sends an INFORM packet and sets up reception for an ACK
     48  *
     49  *   input: dhcp_smach_t *: the state machine to use
     50  *  output: void
     51  *    note: the INFORM cannot be sent successfully if the interface
     52  *	    does not have an IP address (this is mostly an issue for IPv4).
     53  *	    We switch into INFORM_SENT state before sending the packet so
     54  *	    that the packet-sending subsystem uses regular sockets and sets
     55  *	    the source address.  (See set_smach_state.)
     56  */
     57 
     58 void
     59 dhcp_inform(dhcp_smach_t *dsmp)
     60 {
     61 	dhcp_pkt_t		*dpkt;
     62 
     63 	if (!set_smach_state(dsmp, INFORM_SENT))
     64 		goto failed;
     65 
     66 	if (dsmp->dsm_isv6) {
     67 		dpkt = init_pkt(dsmp, DHCPV6_MSG_INFO_REQ);
     68 
     69 		/* Add required Option Request option */
     70 		(void) add_pkt_prl(dpkt, dsmp);
     71 		dsmp->dsm_server = ipv6_all_dhcp_relay_and_servers;
     72 		(void) send_pkt_v6(dsmp, dpkt, dsmp->dsm_server,
     73 		    stop_informing, DHCPV6_INF_TIMEOUT, DHCPV6_INF_MAX_RT);
     74 	} else {
     75 		ipaddr_t server;
     76 
     77 		/*
     78 		 * Assemble a DHCPREQUEST packet, without the Server ID option.
     79 		 * Fill in ciaddr, since we know this.  dsm_server will be set
     80 		 * to the server's IP address, which will be the broadcast
     81 		 * address if we don't know it.  The max DHCP message size
     82 		 * option is set to the interface max, minus the size of the
     83 		 * UDP and IP headers.
     84 		 */
     85 
     86 		dpkt = init_pkt(dsmp, INFORM);
     87 		IN6_V4MAPPED_TO_INADDR(&dsmp->dsm_lif->lif_v6addr,
     88 		    &dpkt->pkt->ciaddr);
     89 
     90 		(void) add_pkt_opt16(dpkt, CD_MAX_DHCP_SIZE,
     91 		    htons(dsmp->dsm_lif->lif_pif->pif_max -
     92 		    sizeof (struct udpiphdr)));
     93 		if (class_id_len != 0) {
     94 			(void) add_pkt_opt(dpkt, CD_CLASS_ID, class_id,
     95 			    class_id_len);
     96 		}
     97 		(void) add_pkt_prl(dpkt, dsmp);
     98 		(void) add_pkt_opt(dpkt, CD_END, NULL, 0);
     99 
    100 		IN6_V4MAPPED_TO_IPADDR(&dsmp->dsm_server, server);
    101 		if (!send_pkt(dsmp, dpkt, server, NULL)) {
    102 			dhcpmsg(MSG_ERROR, "dhcp_inform: send_pkt failed");
    103 			goto failed;
    104 		}
    105 	}
    106 
    107 	return;
    108 
    109 failed:
    110 	dsmp->dsm_dflags |= DHCP_IF_FAILED;
    111 	ipc_action_finish(dsmp, DHCP_IPC_E_INT);
    112 	(void) set_smach_state(dsmp, INIT);
    113 }
    114 
    115 /*
    116  * stop_informing(): decides when to stop retransmitting Information-Requests
    117  *
    118  *   input: dhcp_smach_t *: the state machine Info-Reqs are being sent from
    119  *	    unsigned int: the number of requests sent so far
    120  *  output: boolean_t: B_TRUE if retransmissions should stop
    121  */
    122 
    123 /* ARGSUSED */
    124 static boolean_t
    125 stop_informing(dhcp_smach_t *dsmp, unsigned int n_requests)
    126 {
    127 	return (B_FALSE);
    128 }
    129