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 * INIT_REBOOT state of the DHCP client state machine. 26 */ 27 28 #pragma ident "%Z%%M% %I% %E% SMI" 29 30 #include <sys/types.h> 31 #include <stdio.h> 32 #include <stdlib.h> 33 #include <limits.h> 34 #include <sys/socket.h> 35 #include <netinet/in.h> 36 #include <netinet/dhcp.h> 37 #include <netinet/udp.h> 38 #include <netinet/ip_var.h> 39 #include <netinet/udp_var.h> 40 #include <dhcpmsg.h> 41 #include <string.h> 42 43 #include "agent.h" 44 #include "packet.h" 45 #include "states.h" 46 #include "util.h" 47 #include "interface.h" 48 #include "defaults.h" 49 50 static stop_func_t stop_init_reboot; 51 52 /* 53 * dhcp_init_reboot_v4(): attempts to reuse a cached configuration for a state 54 * machine. 55 * 56 * input: dhcp_smach_t *: the state machine to examine for reuse 57 * output: void 58 */ 59 60 static void 61 dhcp_init_reboot_v4(dhcp_smach_t *dsmp) 62 { 63 dhcp_pkt_t *dpkt; 64 const char *reqhost; 65 char hostfile[PATH_MAX + 1]; 66 67 /* 68 * assemble DHCPREQUEST message. The max dhcp message size 69 * option is set to the interface max, minus the size of the udp and 70 * ip headers. 71 */ 72 73 dpkt = init_pkt(dsmp, REQUEST); 74 (void) add_pkt_opt32(dpkt, CD_REQUESTED_IP_ADDR, 75 dsmp->dsm_ack->pkt->yiaddr.s_addr); 76 77 (void) add_pkt_opt32(dpkt, CD_LEASE_TIME, htonl(DHCP_PERM)); 78 (void) add_pkt_opt16(dpkt, CD_MAX_DHCP_SIZE, 79 htons(dsmp->dsm_lif->lif_pif->pif_max - sizeof (struct udpiphdr))); 80 81 if (class_id_len != 0) 82 (void) add_pkt_opt(dpkt, CD_CLASS_ID, class_id, class_id_len); 83 (void) add_pkt_prl(dpkt, dsmp); 84 85 /* 86 * Set CD_HOSTNAME option if REQUEST_HOSTNAME is set and a hostname 87 * is found in /etc/hostname.<ifname> 88 */ 89 if (df_get_bool(dsmp->dsm_name, dsmp->dsm_isv6, DF_REQUEST_HOSTNAME)) { 90 (void) snprintf(hostfile, sizeof (hostfile), "/etc/hostname.%s", 91 dsmp->dsm_name); 92 93 if ((reqhost = iffile_to_hostname(hostfile)) != NULL) { 94 dhcpmsg(MSG_DEBUG, "dhcp_selecting: host %s", reqhost); 95 if ((dsmp->dsm_reqhost = strdup(reqhost)) != NULL) 96 (void) add_pkt_opt(dpkt, CD_HOSTNAME, 97 dsmp->dsm_reqhost, 98 strlen(dsmp->dsm_reqhost)); 99 else 100 dhcpmsg(MSG_WARNING, "dhcp_selecting: cannot" 101 " allocate memory for host name option"); 102 } else { 103 dhcpmsg(MSG_DEBUG, 104 "dhcp_selecting: no hostname for %s", 105 dsmp->dsm_name); 106 } 107 } 108 109 (void) add_pkt_opt(dpkt, CD_END, NULL, 0); 110 111 (void) send_pkt(dsmp, dpkt, htonl(INADDR_BROADCAST), stop_init_reboot); 112 } 113 114 115 /* 116 * dhcp_init_reboot_v6(): attempts to reuse a cached configuration for a state 117 * machine. Create a Confirm message and multicast it 118 * out. 119 * 120 * input: dhcp_smach_t *: the state machine to examine for reuse 121 * output: void 122 */ 123 124 static void 125 dhcp_init_reboot_v6(dhcp_smach_t *dsmp) 126 { 127 dhcp_pkt_t *dpkt; 128 dhcpv6_option_t *d6o, *d6so, *popt; 129 uint_t olen, solen; 130 dhcpv6_ia_na_t d6in; 131 dhcpv6_iaaddr_t d6ia; 132 char *obase; 133 134 /* 135 * Assemble a Confirm message based on the current ack. 136 */ 137 138 dpkt = init_pkt(dsmp, DHCPV6_MSG_CONFIRM); 139 140 /* 141 * Loop over and copy IA_NAs and IAADDRs we have in our last ack. This 142 * is what we'll be requesting. 143 */ 144 d6o = NULL; 145 while ((d6o = dhcpv6_pkt_option(dsmp->dsm_ack, d6o, DHCPV6_OPT_IA_NA, 146 &olen)) != NULL) { 147 148 /* 149 * Copy in IA_NA option from the ack. Note that we use zero 150 * for all timers in accordance with RFC 3315. (It would make 151 * some sense to say what we think the current timers are as 152 * a hint to the server, but the RFC doesn't agree.) 153 */ 154 if (olen < sizeof (dhcpv6_ia_na_t)) 155 continue; 156 (void) memcpy(&d6in, d6o, sizeof (d6in)); 157 d6in.d6in_t1 = 0; 158 d6in.d6in_t2 = 0; 159 popt = add_pkt_opt(dpkt, DHCPV6_OPT_IA_NA, 160 (char *)&d6in + sizeof (*d6o), 161 sizeof (d6in) - sizeof (*d6o)); 162 if (popt == NULL) 163 goto failure; 164 165 /* 166 * Now loop over the IAADDR suboptions and add those. 167 */ 168 obase = (char *)d6o + sizeof (dhcpv6_ia_na_t); 169 olen -= sizeof (dhcpv6_ia_na_t); 170 d6so = NULL; 171 while ((d6so = dhcpv6_find_option(obase, olen, d6so, 172 DHCPV6_OPT_IAADDR, &solen)) != NULL) { 173 if (solen < sizeof (dhcpv6_iaaddr_t)) 174 continue; 175 (void) memcpy(&d6ia, d6so, sizeof (d6ia)); 176 d6ia.d6ia_preflife = 0; 177 d6ia.d6ia_vallife = 0; 178 if (add_pkt_subopt(dpkt, popt, DHCPV6_OPT_IAADDR, 179 (char *)&d6ia + sizeof (*d6so), 180 sizeof (d6ia) - sizeof (*d6so)) == NULL) 181 goto failure; 182 } 183 } 184 185 /* Add required Option Request option */ 186 (void) add_pkt_prl(dpkt, dsmp); 187 188 (void) send_pkt_v6(dsmp, dpkt, ipv6_all_dhcp_relay_and_servers, 189 stop_init_reboot, DHCPV6_CNF_TIMEOUT, DHCPV6_CNF_MAX_RT); 190 191 return; 192 193 failure: 194 if (iu_schedule_timer_ms(tq, lrand48() % DHCP_SELECT_WAIT, dhcp_start, 195 dsmp) != -1) 196 hold_smach(dsmp); 197 else 198 dhcp_selecting(dsmp); 199 } 200 201 /* 202 * dhcp_init_reboot(): attempts to reuse a cached configuration for a state 203 * machine. 204 * 205 * input: dhcp_smach_t *: the state machine to examine for reuse 206 * output: void 207 */ 208 209 void 210 dhcp_init_reboot(dhcp_smach_t *dsmp) 211 { 212 dhcpmsg(MSG_VERBOSE, "%s has cached configuration - entering " 213 "INIT_REBOOT", dsmp->dsm_name); 214 215 if (!set_smach_state(dsmp, INIT_REBOOT)) { 216 dhcpmsg(MSG_ERROR, "dhcp_init_reboot: cannot register to " 217 "collect ACK/NAK packets, reverting to INIT on %s", 218 dsmp->dsm_name); 219 220 dsmp->dsm_dflags |= DHCP_IF_FAILED; 221 (void) set_smach_state(dsmp, INIT); 222 ipc_action_finish(dsmp, DHCP_IPC_E_MEMORY); 223 return; 224 } 225 226 if (dsmp->dsm_isv6) 227 dhcp_init_reboot_v6(dsmp); 228 else 229 dhcp_init_reboot_v4(dsmp); 230 } 231 232 /* 233 * stop_init_reboot(): decides when to stop retransmitting REQUESTs 234 * 235 * input: dhcp_smach_t *: the state machine sending the REQUESTs 236 * unsigned int: the number of REQUESTs sent so far 237 * output: boolean_t: B_TRUE if retransmissions should stop 238 */ 239 240 static boolean_t 241 stop_init_reboot(dhcp_smach_t *dsmp, unsigned int n_requests) 242 { 243 if (dsmp->dsm_isv6) { 244 uint_t nowabs, maxabs; 245 246 nowabs = gethrtime() / (NANOSEC / MILLISEC); 247 maxabs = dsmp->dsm_neg_hrtime / (NANOSEC / MILLISEC) + 248 DHCPV6_CNF_MAX_RD; 249 if (nowabs < maxabs) { 250 /* Cap the timer based on the maximum */ 251 if (nowabs + dsmp->dsm_send_timeout > maxabs) 252 dsmp->dsm_send_timeout = maxabs - nowabs; 253 return (B_FALSE); 254 } 255 dhcpmsg(MSG_INFO, "no Reply to Confirm, using remainder of " 256 "existing lease on %s", dsmp->dsm_name); 257 } else { 258 if (n_requests < DHCP_MAX_REQUESTS) 259 return (B_FALSE); 260 dhcpmsg(MSG_INFO, "no ACK/NAK to INIT_REBOOT REQUEST, " 261 "using remainder of existing lease on %s", dsmp->dsm_name); 262 } 263 264 /* 265 * We already stuck our old ack in dsmp->dsm_ack and relativized the 266 * packet times, so we can just pretend that the server sent it to us 267 * and move to bound. If that fails, fall back to selecting. 268 */ 269 270 if (dhcp_bound(dsmp, NULL)) { 271 if (dsmp->dsm_isv6) { 272 if (!save_server_id(dsmp, dsmp->dsm_ack)) 273 goto failure; 274 server_unicast_option(dsmp, dsmp->dsm_ack); 275 } 276 } else { 277 failure: 278 dhcpmsg(MSG_INFO, "unable to use saved lease on %s; restarting", 279 dsmp->dsm_name); 280 dhcp_selecting(dsmp); 281 } 282 283 return (B_TRUE); 284 } 285