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 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #include <sys/types.h> 28 #include <sys/systm.h> 29 #include <sys/stream.h> 30 #include <sys/ddi.h> 31 #include <sys/sunddi.h> 32 #include <sys/strsubr.h> 33 #include <sys/strsun.h> 34 35 #include <netinet/in.h> 36 #include <netinet/ip6.h> 37 38 #include <inet/common.h> 39 #include <inet/ip.h> 40 #include <inet/ip6.h> 41 #include <inet/mib2.h> 42 #include <inet/nd.h> 43 #include <inet/optcom.h> 44 #include <inet/sctp_ip.h> 45 #include <inet/ipclassifier.h> 46 #include "sctp_impl.h" 47 48 void 49 sctp_send_shutdown(sctp_t *sctp, int rexmit) 50 { 51 mblk_t *smp; 52 mblk_t *sendmp; 53 sctp_chunk_hdr_t *sch; 54 uint32_t *ctsn; 55 sctp_faddr_t *fp; 56 sctp_stack_t *sctps = sctp->sctp_sctps; 57 58 if (sctp->sctp_state != SCTPS_ESTABLISHED && 59 sctp->sctp_state != SCTPS_SHUTDOWN_PENDING && 60 sctp->sctp_state != SCTPS_SHUTDOWN_SENT) { 61 return; 62 } 63 64 if (sctp->sctp_state == SCTPS_ESTABLISHED) { 65 sctp->sctp_state = SCTPS_SHUTDOWN_PENDING; 66 /* 67 * We set an upper bound on how long we will 68 * wait for a shutdown-ack from the peer. This 69 * is to prevent the receiver from attempting 70 * to create a half-closed state indefinately. 71 * See archive from IETF TSVWG mailing list 72 * for June 2001 for more information. 73 * Since we will not be calculating RTTs after 74 * sending the shutdown, we can overload out_time 75 * to track how long we have waited. 76 */ 77 sctp->sctp_out_time = lbolt64; 78 } 79 80 /* 81 * If there is unsent (or unacked) data, wait for it to get ack'd 82 */ 83 if (sctp->sctp_xmit_head != NULL || sctp->sctp_xmit_unsent != NULL) { 84 return; 85 } 86 87 /* rotate faddrs if we are retransmitting */ 88 if (!rexmit) { 89 fp = sctp->sctp_current; 90 } else { 91 fp = sctp_rotate_faddr(sctp, sctp->sctp_shutdown_faddr); 92 } 93 94 sctp->sctp_shutdown_faddr = fp; 95 96 /* Link in a SACK if resending the shutdown */ 97 if (sctp->sctp_state > SCTPS_SHUTDOWN_PENDING && 98 (sendmp = sctp_make_sack(sctp, fp, NULL)) != NULL) { 99 100 smp = allocb(sizeof (*sch) + sizeof (*ctsn), BPRI_MED); 101 if (smp == NULL) { 102 freemsg(sendmp); 103 goto done; 104 } 105 linkb(sendmp, smp); 106 107 sch = (sctp_chunk_hdr_t *)smp->b_rptr; 108 smp->b_wptr = smp->b_rptr + sizeof (*sch) + sizeof (*ctsn); 109 } else { 110 sendmp = sctp_make_mp(sctp, fp, 111 sizeof (*sch) + sizeof (*ctsn)); 112 if (sendmp == NULL) { 113 SCTP_KSTAT(sctps, sctp_send_shutdown_failed); 114 goto done; 115 } 116 sch = (sctp_chunk_hdr_t *)sendmp->b_wptr; 117 sendmp->b_wptr += sizeof (*sch) + sizeof (*ctsn); 118 119 /* shutdown w/o sack, update lastacked */ 120 sctp->sctp_lastacked = sctp->sctp_ftsn - 1; 121 } 122 123 sch->sch_id = CHUNK_SHUTDOWN; 124 sch->sch_flags = 0; 125 sch->sch_len = htons(sizeof (*sch) + sizeof (*ctsn)); 126 127 ctsn = (uint32_t *)(sch + 1); 128 *ctsn = htonl(sctp->sctp_lastacked); 129 130 /* Link the shutdown chunk in after the IP/SCTP header */ 131 132 sctp_set_iplen(sctp, sendmp); 133 134 BUMP_LOCAL(sctp->sctp_obchunks); 135 136 /* Send the shutdown and restart the timer */ 137 sctp_add_sendq(sctp, sendmp); 138 139 done: 140 sctp->sctp_state = SCTPS_SHUTDOWN_SENT; 141 SCTP_FADDR_TIMER_RESTART(sctp, sctp->sctp_current, 142 sctp->sctp_current->rto); 143 } 144 145 int 146 sctp_shutdown_received(sctp_t *sctp, sctp_chunk_hdr_t *sch, boolean_t crwsd, 147 boolean_t rexmit, sctp_faddr_t *fp) 148 { 149 mblk_t *samp; 150 sctp_chunk_hdr_t *sach; 151 uint32_t *tsn; 152 int trysend = 0; 153 sctp_stack_t *sctps = sctp->sctp_sctps; 154 155 if (sctp->sctp_state != SCTPS_SHUTDOWN_ACK_SENT) 156 sctp->sctp_state = SCTPS_SHUTDOWN_RECEIVED; 157 158 /* Extract and process the TSN in the shutdown chunk */ 159 if (sch != NULL) { 160 tsn = (uint32_t *)(sch + 1); 161 trysend = sctp_cumack(sctp, ntohl(*tsn), &samp); 162 } 163 164 /* Don't allow sending new data */ 165 if (!SCTP_IS_DETACHED(sctp) && !sctp->sctp_ulp_discon_done) { 166 sctp->sctp_ulp_opctl(sctp->sctp_ulpd, SOCK_OPCTL_SHUT_SEND, 0); 167 sctp->sctp_ulp_discon_done = B_TRUE; 168 } 169 170 /* 171 * If there is unsent or unacked data, try sending them out now. 172 * The other side should acknowledge them. After we have flushed 173 * the transmit queue, we can complete the shutdown sequence. 174 */ 175 if (sctp->sctp_xmit_head != NULL || sctp->sctp_xmit_unsent != NULL) 176 return (1); 177 178 if (fp == NULL) { 179 /* rotate faddrs if we are retransmitting */ 180 if (!rexmit) 181 fp = sctp->sctp_current; 182 else 183 fp = sctp_rotate_faddr(sctp, sctp->sctp_shutdown_faddr); 184 } 185 sctp->sctp_shutdown_faddr = fp; 186 187 samp = sctp_make_mp(sctp, fp, sizeof (*sach)); 188 if (samp == NULL) { 189 SCTP_KSTAT(sctps, sctp_send_shutdown_ack_failed); 190 goto dotimer; 191 } 192 193 sach = (sctp_chunk_hdr_t *)samp->b_wptr; 194 sach->sch_id = CHUNK_SHUTDOWN_ACK; 195 sach->sch_flags = 0; 196 sach->sch_len = htons(sizeof (*sach)); 197 198 samp->b_wptr += sizeof (*sach); 199 200 /* 201 * bundle a "cookie received while shutting down" error if 202 * the caller asks for it. 203 */ 204 if (crwsd) { 205 mblk_t *errmp; 206 207 errmp = sctp_make_err(sctp, SCTP_ERR_COOKIE_SHUT, NULL, 0); 208 if (errmp != NULL) { 209 linkb(samp, errmp); 210 BUMP_LOCAL(sctp->sctp_obchunks); 211 } 212 } 213 214 sctp_set_iplen(sctp, samp); 215 216 BUMP_LOCAL(sctp->sctp_obchunks); 217 218 sctp_add_sendq(sctp, samp); 219 220 dotimer: 221 sctp->sctp_state = SCTPS_SHUTDOWN_ACK_SENT; 222 SCTP_FADDR_TIMER_RESTART(sctp, sctp->sctp_current, 223 sctp->sctp_current->rto); 224 225 return (trysend); 226 } 227 228 void 229 sctp_shutdown_complete(sctp_t *sctp) 230 { 231 mblk_t *scmp; 232 sctp_chunk_hdr_t *scch; 233 sctp_stack_t *sctps = sctp->sctp_sctps; 234 235 scmp = sctp_make_mp(sctp, NULL, sizeof (*scch)); 236 if (scmp == NULL) { 237 /* XXX use timer approach */ 238 SCTP_KSTAT(sctps, sctp_send_shutdown_comp_failed); 239 return; 240 } 241 242 scch = (sctp_chunk_hdr_t *)scmp->b_wptr; 243 scch->sch_id = CHUNK_SHUTDOWN_COMPLETE; 244 scch->sch_flags = 0; 245 scch->sch_len = htons(sizeof (*scch)); 246 247 scmp->b_wptr += sizeof (*scch); 248 249 sctp_set_iplen(sctp, scmp); 250 251 BUMP_LOCAL(sctp->sctp_obchunks); 252 253 sctp_add_sendq(sctp, scmp); 254 } 255 256 /* 257 * Similar to sctp_shutdown_complete(), except that since this 258 * is out-of-the-blue, we can't use an sctp's association information, 259 * and instead must draw all necessary info from the incoming packet. 260 */ 261 void 262 sctp_ootb_shutdown_ack(sctp_t *gsctp, mblk_t *inmp, uint_t ip_hdr_len) 263 { 264 boolean_t isv4; 265 ipha_t *inip4h; 266 ip6_t *inip6h; 267 sctp_hdr_t *insctph; 268 sctp_chunk_hdr_t *scch; 269 int i; 270 uint16_t port; 271 mblk_t *mp1; 272 sctp_stack_t *sctps = gsctp->sctp_sctps; 273 274 isv4 = (IPH_HDR_VERSION(inmp->b_rptr) == IPV4_VERSION); 275 276 /* 277 * The gsctp should contain the minimal IP header. So the 278 * incoming mblk should be able to hold the new SCTP packet. 279 */ 280 ASSERT(MBLKL(inmp) >= sizeof (*insctph) + sizeof (*scch) + 281 (isv4 ? gsctp->sctp_ip_hdr_len : gsctp->sctp_ip_hdr6_len)); 282 283 /* 284 * Check to see if we can reuse the incoming mblk. There should 285 * not be other reference and the db_base of the mblk should be 286 * properly aligned. Since this packet comes from below, 287 * there should be enough header space to fill in what the lower 288 * layers want to add. And we will not stash anything there. 289 */ 290 if (!IS_P2ALIGNED(DB_BASE(inmp), sizeof (ire_t *)) || 291 DB_REF(inmp) != 1) { 292 mp1 = allocb(MBLKL(inmp) + sctps->sctps_wroff_xtra, BPRI_MED); 293 if (mp1 == NULL) { 294 freeb(inmp); 295 return; 296 } 297 mp1->b_rptr += sctps->sctps_wroff_xtra; 298 mp1->b_wptr = mp1->b_rptr + MBLKL(inmp); 299 bcopy(inmp->b_rptr, mp1->b_rptr, MBLKL(inmp)); 300 freeb(inmp); 301 inmp = mp1; 302 } else { 303 ASSERT(DB_CKSUMFLAGS(inmp) == 0); 304 } 305 306 /* 307 * We follow the logic in tcp_xmit_early_reset() in that we skip 308 * reversing source route (i.e. relpace all IP options with EOL). 309 */ 310 if (isv4) { 311 ipaddr_t v4addr; 312 313 inip4h = (ipha_t *)inmp->b_rptr; 314 for (i = IP_SIMPLE_HDR_LENGTH; i < (int)ip_hdr_len; i++) 315 inmp->b_rptr[i] = IPOPT_EOL; 316 /* Swap addresses */ 317 inip4h->ipha_length = htons(ip_hdr_len + sizeof (*insctph) + 318 sizeof (*scch)); 319 v4addr = inip4h->ipha_src; 320 inip4h->ipha_src = inip4h->ipha_dst; 321 inip4h->ipha_dst = v4addr; 322 inip4h->ipha_ident = 0; 323 inip4h->ipha_ttl = (uchar_t)sctps->sctps_ipv4_ttl; 324 } else { 325 in6_addr_t v6addr; 326 327 inip6h = (ip6_t *)inmp->b_rptr; 328 /* Remove any extension headers assuming partial overlay */ 329 if (ip_hdr_len > IPV6_HDR_LEN) { 330 uint8_t *to; 331 332 to = inmp->b_rptr + ip_hdr_len - IPV6_HDR_LEN; 333 ovbcopy(inip6h, to, IPV6_HDR_LEN); 334 inmp->b_rptr += ip_hdr_len - IPV6_HDR_LEN; 335 ip_hdr_len = IPV6_HDR_LEN; 336 inip6h = (ip6_t *)inmp->b_rptr; 337 inip6h->ip6_nxt = IPPROTO_SCTP; 338 } 339 inip6h->ip6_plen = htons(ip_hdr_len + sizeof (*insctph) + 340 sizeof (*scch) - IPV6_HDR_LEN); 341 v6addr = inip6h->ip6_src; 342 inip6h->ip6_src = inip6h->ip6_dst; 343 inip6h->ip6_dst = v6addr; 344 inip6h->ip6_hops = (uchar_t)sctps->sctps_ipv6_hoplimit; 345 } 346 insctph = (sctp_hdr_t *)(inmp->b_rptr + ip_hdr_len); 347 348 /* Swap ports. Verification tag is reused. */ 349 port = insctph->sh_sport; 350 insctph->sh_sport = insctph->sh_dport; 351 insctph->sh_dport = port; 352 353 /* Lay in the shutdown complete chunk */ 354 scch = (sctp_chunk_hdr_t *)(insctph + 1); 355 scch->sch_id = CHUNK_SHUTDOWN_COMPLETE; 356 scch->sch_len = htons(sizeof (*scch)); 357 scch->sch_flags = 0; 358 359 /* Set the T-bit */ 360 SCTP_SET_TBIT(scch); 361 362 BUMP_LOCAL(gsctp->sctp_obchunks); 363 /* Nothing to stash... */ 364 SCTP_STASH_IPINFO(inmp, (ire_t *)NULL); 365 366 sctp_add_sendq(gsctp, inmp); 367 } 368