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 2009 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 #include <sys/types.h> 29 #include <stdio.h> 30 #include <limits.h> 31 #include <sys/socket.h> 32 #include <netinet/in.h> 33 #include <netinet/dhcp.h> 34 #include <netinet/udp.h> 35 #include <netinet/ip_var.h> 36 #include <netinet/udp_var.h> 37 #include <dhcpmsg.h> 38 #include <string.h> 39 40 #include "agent.h" 41 #include "packet.h" 42 #include "states.h" 43 #include "util.h" 44 #include "interface.h" 45 #include "defaults.h" 46 47 static stop_func_t stop_init_reboot; 48 49 /* 50 * dhcp_init_reboot_v4(): attempts to reuse a cached configuration for a state 51 * machine. 52 * 53 * input: dhcp_smach_t *: the state machine to examine for reuse 54 * output: void 55 */ 56 57 static void 58 dhcp_init_reboot_v4(dhcp_smach_t *dsmp) 59 { 60 dhcp_pkt_t *dpkt; 61 const char *reqhost; 62 char hostfile[PATH_MAX + 1]; 63 64 /* 65 * assemble DHCPREQUEST message. The max dhcp message size 66 * option is set to the interface max, minus the size of the udp and 67 * ip headers. 68 */ 69 70 dpkt = init_pkt(dsmp, REQUEST); 71 (void) add_pkt_opt32(dpkt, CD_REQUESTED_IP_ADDR, 72 dsmp->dsm_ack->pkt->yiaddr.s_addr); 73 74 (void) add_pkt_opt32(dpkt, CD_LEASE_TIME, htonl(DHCP_PERM)); 75 (void) add_pkt_opt16(dpkt, CD_MAX_DHCP_SIZE, 76 htons(dsmp->dsm_lif->lif_pif->pif_max - sizeof (struct udpiphdr))); 77 78 if (class_id_len != 0) 79 (void) add_pkt_opt(dpkt, CD_CLASS_ID, class_id, class_id_len); 80 (void) add_pkt_prl(dpkt, dsmp); 81 82 /* 83 * Set CD_HOSTNAME option if REQUEST_HOSTNAME is set and a hostname 84 * is found in /etc/hostname.<ifname> 85 */ 86 if (df_get_bool(dsmp->dsm_name, dsmp->dsm_isv6, DF_REQUEST_HOSTNAME)) { 87 (void) snprintf(hostfile, sizeof (hostfile), "/etc/hostname.%s", 88 dsmp->dsm_name); 89 90 if ((reqhost = iffile_to_hostname(hostfile)) != NULL) { 91 dhcpmsg(MSG_DEBUG, "dhcp_selecting: host %s", reqhost); 92 if ((dsmp->dsm_reqhost = strdup(reqhost)) != NULL) 93 (void) add_pkt_opt(dpkt, CD_HOSTNAME, 94 dsmp->dsm_reqhost, 95 strlen(dsmp->dsm_reqhost)); 96 else 97 dhcpmsg(MSG_WARNING, "dhcp_selecting: cannot" 98 " allocate memory for host name option"); 99 } else { 100 dhcpmsg(MSG_DEBUG, 101 "dhcp_selecting: no hostname for %s", 102 dsmp->dsm_name); 103 } 104 } 105 106 (void) add_pkt_opt(dpkt, CD_END, NULL, 0); 107 108 (void) send_pkt(dsmp, dpkt, htonl(INADDR_BROADCAST), stop_init_reboot); 109 } 110 111 112 /* 113 * dhcp_init_reboot_v6(): attempts to reuse a cached configuration for a state 114 * machine. Create a Confirm message and multicast it 115 * out. 116 * 117 * input: dhcp_smach_t *: the state machine to examine for reuse 118 * output: void 119 */ 120 121 static void 122 dhcp_init_reboot_v6(dhcp_smach_t *dsmp) 123 { 124 dhcp_pkt_t *dpkt; 125 dhcpv6_option_t *d6o, *d6so, *popt; 126 uint_t olen, solen; 127 dhcpv6_ia_na_t d6in; 128 dhcpv6_iaaddr_t d6ia; 129 char *obase; 130 131 /* 132 * Assemble a Confirm message based on the current ack. 133 */ 134 135 dpkt = init_pkt(dsmp, DHCPV6_MSG_CONFIRM); 136 137 /* 138 * Loop over and copy IA_NAs and IAADDRs we have in our last ack. This 139 * is what we'll be requesting. 140 */ 141 d6o = NULL; 142 while ((d6o = dhcpv6_pkt_option(dsmp->dsm_ack, d6o, DHCPV6_OPT_IA_NA, 143 &olen)) != NULL) { 144 145 /* 146 * Copy in IA_NA option from the ack. Note that we use zero 147 * for all timers in accordance with RFC 3315. (It would make 148 * some sense to say what we think the current timers are as 149 * a hint to the server, but the RFC doesn't agree.) 150 */ 151 if (olen < sizeof (dhcpv6_ia_na_t)) 152 continue; 153 (void) memcpy(&d6in, d6o, sizeof (d6in)); 154 d6in.d6in_t1 = 0; 155 d6in.d6in_t2 = 0; 156 popt = add_pkt_opt(dpkt, DHCPV6_OPT_IA_NA, 157 (char *)&d6in + sizeof (*d6o), 158 sizeof (d6in) - sizeof (*d6o)); 159 if (popt == NULL) 160 goto failure; 161 162 /* 163 * Now loop over the IAADDR suboptions and add those. 164 */ 165 obase = (char *)d6o + sizeof (dhcpv6_ia_na_t); 166 olen -= sizeof (dhcpv6_ia_na_t); 167 d6so = NULL; 168 while ((d6so = dhcpv6_find_option(obase, olen, d6so, 169 DHCPV6_OPT_IAADDR, &solen)) != NULL) { 170 if (solen < sizeof (dhcpv6_iaaddr_t)) 171 continue; 172 (void) memcpy(&d6ia, d6so, sizeof (d6ia)); 173 d6ia.d6ia_preflife = 0; 174 d6ia.d6ia_vallife = 0; 175 if (add_pkt_subopt(dpkt, popt, DHCPV6_OPT_IAADDR, 176 (char *)&d6ia + sizeof (*d6so), 177 sizeof (d6ia) - sizeof (*d6so)) == NULL) 178 goto failure; 179 } 180 } 181 182 /* Add required Option Request option */ 183 (void) add_pkt_prl(dpkt, dsmp); 184 185 (void) send_pkt_v6(dsmp, dpkt, ipv6_all_dhcp_relay_and_servers, 186 stop_init_reboot, DHCPV6_CNF_TIMEOUT, DHCPV6_CNF_MAX_RT); 187 188 return; 189 190 failure: 191 if (!set_start_timer(dsmp)) 192 dhcp_selecting(dsmp); 193 } 194 195 /* 196 * dhcp_init_reboot(): attempts to reuse a cached configuration for a state 197 * machine. 198 * 199 * input: dhcp_smach_t *: the state machine to examine for reuse 200 * output: void 201 */ 202 203 void 204 dhcp_init_reboot(dhcp_smach_t *dsmp) 205 { 206 dhcpmsg(MSG_VERBOSE, "%s has cached configuration - entering " 207 "INIT_REBOOT", dsmp->dsm_name); 208 209 if (!set_smach_state(dsmp, INIT_REBOOT)) { 210 dhcpmsg(MSG_ERROR, "dhcp_init_reboot: cannot register to " 211 "collect ACK/NAK packets, reverting to INIT on %s", 212 dsmp->dsm_name); 213 214 dsmp->dsm_dflags |= DHCP_IF_FAILED; 215 (void) set_smach_state(dsmp, INIT); 216 ipc_action_finish(dsmp, DHCP_IPC_E_MEMORY); 217 return; 218 } 219 220 if (dsmp->dsm_isv6) 221 dhcp_init_reboot_v6(dsmp); 222 else 223 dhcp_init_reboot_v4(dsmp); 224 } 225 226 /* 227 * stop_init_reboot(): decides when to stop retransmitting REQUESTs 228 * 229 * input: dhcp_smach_t *: the state machine sending the REQUESTs 230 * unsigned int: the number of REQUESTs sent so far 231 * output: boolean_t: B_TRUE if retransmissions should stop 232 */ 233 234 static boolean_t 235 stop_init_reboot(dhcp_smach_t *dsmp, unsigned int n_requests) 236 { 237 if (dsmp->dsm_isv6) { 238 uint_t nowabs, maxabs; 239 240 nowabs = NSEC2MSEC(gethrtime()); 241 maxabs = NSEC2MSEC(dsmp->dsm_neg_hrtime) + DHCPV6_CNF_MAX_RD; 242 if (nowabs < maxabs) { 243 /* Cap the timer based on the maximum */ 244 if (nowabs + dsmp->dsm_send_timeout > maxabs) 245 dsmp->dsm_send_timeout = maxabs - nowabs; 246 return (B_FALSE); 247 } 248 } else { 249 if (n_requests < DHCP_MAX_REQUESTS) 250 return (B_FALSE); 251 } 252 253 if (df_get_bool(dsmp->dsm_name, dsmp->dsm_isv6, 254 DF_VERIFIED_LEASE_ONLY)) { 255 dhcpmsg(MSG_INFO, 256 "unable to verify existing lease on %s; restarting", 257 dsmp->dsm_name); 258 dhcp_selecting(dsmp); 259 return (B_TRUE); 260 } 261 262 if (dsmp->dsm_isv6) { 263 dhcpmsg(MSG_INFO, "no Reply to Confirm, using remainder of " 264 "existing lease on %s", dsmp->dsm_name); 265 } else { 266 dhcpmsg(MSG_INFO, "no ACK/NAK to INIT_REBOOT REQUEST, " 267 "using remainder of existing lease on %s", dsmp->dsm_name); 268 } 269 270 /* 271 * We already stuck our old ack in dsmp->dsm_ack and relativized the 272 * packet times, so we can just pretend that the server sent it to us 273 * and move to bound. If that fails, fall back to selecting. 274 */ 275 276 if (dhcp_bound(dsmp, NULL)) { 277 if (dsmp->dsm_isv6) { 278 if (!save_server_id(dsmp, dsmp->dsm_ack)) 279 goto failure; 280 server_unicast_option(dsmp, dsmp->dsm_ack); 281 } 282 } else { 283 failure: 284 dhcpmsg(MSG_INFO, "unable to use saved lease on %s; restarting", 285 dsmp->dsm_name); 286 dhcp_selecting(dsmp); 287 } 288 289 return (B_TRUE); 290 } 291