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