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 2006 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/types.h> 30 #include <sys/systm.h> 31 #include <sys/stream.h> 32 #include <sys/ddi.h> 33 #include <sys/sunddi.h> 34 #include <sys/strsubr.h> 35 #include <sys/strsun.h> 36 37 #include <netinet/in.h> 38 #include <netinet/ip6.h> 39 40 #include <inet/common.h> 41 #include <inet/ip.h> 42 #include <inet/ip6.h> 43 #include <inet/mib2.h> 44 #include <inet/nd.h> 45 #include <inet/optcom.h> 46 #include <inet/sctp_ip.h> 47 #include "sctp_impl.h" 48 49 void 50 sctp_send_shutdown(sctp_t *sctp, int rexmit) 51 { 52 mblk_t *smp; 53 mblk_t *sendmp; 54 sctp_chunk_hdr_t *sch; 55 uint32_t *ctsn; 56 sctp_faddr_t *fp; 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(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; 153 154 if (sctp->sctp_state != SCTPS_SHUTDOWN_ACK_SENT) 155 sctp->sctp_state = SCTPS_SHUTDOWN_RECEIVED; 156 157 /* Extract and process the TSN in the shutdown chunk */ 158 if (sch != NULL) { 159 tsn = (uint32_t *)(sch + 1); 160 trysend = sctp_cumack(sctp, ntohl(*tsn), &samp); 161 } 162 163 /* Don't allow sending new data */ 164 if (!SCTP_IS_DETACHED(sctp)) 165 sctp->sctp_ulp_disconnecting(sctp->sctp_ulpd); 166 167 /* 168 * If there is unsent or unacked data, try sending them out now. 169 * The other side should acknowledge them. After we have flushed 170 * the transmit queue, we can complete the shutdown sequence. 171 */ 172 if (sctp->sctp_xmit_head != NULL || sctp->sctp_xmit_unsent != NULL) 173 return (1); 174 175 if (fp == NULL) { 176 /* rotate faddrs if we are retransmitting */ 177 if (!rexmit) 178 fp = sctp->sctp_current; 179 else 180 fp = sctp_rotate_faddr(sctp, sctp->sctp_shutdown_faddr); 181 } 182 sctp->sctp_shutdown_faddr = fp; 183 184 samp = sctp_make_mp(sctp, fp, sizeof (*sach)); 185 if (samp == NULL) { 186 SCTP_KSTAT(sctp_send_shutdown_ack_failed); 187 goto dotimer; 188 } 189 190 sach = (sctp_chunk_hdr_t *)samp->b_wptr; 191 sach->sch_id = CHUNK_SHUTDOWN_ACK; 192 sach->sch_flags = 0; 193 sach->sch_len = htons(sizeof (*sach)); 194 195 samp->b_wptr += sizeof (*sach); 196 197 /* 198 * bundle a "cookie received while shutting down" error if 199 * the caller asks for it. 200 */ 201 if (crwsd) { 202 mblk_t *errmp; 203 204 errmp = sctp_make_err(sctp, SCTP_ERR_COOKIE_SHUT, NULL, 0); 205 if (errmp != NULL) { 206 linkb(samp, errmp); 207 BUMP_LOCAL(sctp->sctp_obchunks); 208 } 209 } 210 211 sctp_set_iplen(sctp, samp); 212 213 BUMP_LOCAL(sctp->sctp_obchunks); 214 215 sctp_add_sendq(sctp, samp); 216 217 dotimer: 218 sctp->sctp_state = SCTPS_SHUTDOWN_ACK_SENT; 219 SCTP_FADDR_TIMER_RESTART(sctp, sctp->sctp_current, 220 sctp->sctp_current->rto); 221 222 return (trysend); 223 } 224 225 void 226 sctp_shutdown_complete(sctp_t *sctp) 227 { 228 mblk_t *scmp; 229 sctp_chunk_hdr_t *scch; 230 231 scmp = sctp_make_mp(sctp, NULL, sizeof (*scch)); 232 if (scmp == NULL) { 233 /* XXX use timer approach */ 234 SCTP_KSTAT(sctp_send_shutdown_comp_failed); 235 return; 236 } 237 238 scch = (sctp_chunk_hdr_t *)scmp->b_wptr; 239 scch->sch_id = CHUNK_SHUTDOWN_COMPLETE; 240 scch->sch_flags = 0; 241 scch->sch_len = htons(sizeof (*scch)); 242 243 scmp->b_wptr += sizeof (*scch); 244 245 sctp_set_iplen(sctp, scmp); 246 247 BUMP_LOCAL(sctp->sctp_obchunks); 248 249 sctp_add_sendq(sctp, scmp); 250 } 251 252 /* 253 * Similar to sctp_shutdown_complete(), except that since this 254 * is out-of-the-blue, we can't use an sctp's association information, 255 * and instead must draw all necessary info from the incoming packet. 256 */ 257 void 258 sctp_ootb_shutdown_ack(sctp_t *gsctp, mblk_t *inmp, uint_t ip_hdr_len) 259 { 260 boolean_t isv4; 261 ipha_t *inip4h; 262 ip6_t *inip6h; 263 sctp_hdr_t *insctph; 264 sctp_chunk_hdr_t *scch; 265 int i; 266 uint16_t port; 267 mblk_t *mp1; 268 269 isv4 = (IPH_HDR_VERSION(inmp->b_rptr) == IPV4_VERSION); 270 271 /* 272 * The gsctp should contain the minimal IP header. So the 273 * incoming mblk should be able to hold the new SCTP packet. 274 */ 275 ASSERT(MBLKL(inmp) >= sizeof (*insctph) + sizeof (*scch) + 276 (isv4 ? gsctp->sctp_ip_hdr_len : gsctp->sctp_ip_hdr6_len)); 277 278 /* 279 * Check to see if we can reuse the incoming mblk. There should 280 * not be other reference and the db_base of the mblk should be 281 * properly aligned. Since this packet comes from below, 282 * there should be enough header space to fill in what the lower 283 * layers want to add. And we will not stash anything there. 284 */ 285 if (!IS_P2ALIGNED(DB_BASE(inmp), sizeof (ire_t *)) || 286 DB_REF(inmp) != 1) { 287 mp1 = allocb(MBLKL(inmp) + sctp_wroff_xtra, BPRI_MED); 288 if (mp1 == NULL) { 289 freeb(inmp); 290 return; 291 } 292 mp1->b_rptr += sctp_wroff_xtra; 293 mp1->b_wptr = mp1->b_rptr + MBLKL(inmp); 294 bcopy(inmp->b_rptr, mp1->b_rptr, MBLKL(inmp)); 295 freeb(inmp); 296 inmp = mp1; 297 } else { 298 ASSERT(DB_CKSUMFLAGS(inmp) == 0); 299 } 300 301 /* 302 * We follow the logic in tcp_xmit_early_reset() in that we skip 303 * reversing source route (i.e. relpace all IP options with EOL). 304 */ 305 if (isv4) { 306 ipaddr_t v4addr; 307 308 inip4h = (ipha_t *)inmp->b_rptr; 309 for (i = IP_SIMPLE_HDR_LENGTH; i < (int)ip_hdr_len; i++) 310 inmp->b_rptr[i] = IPOPT_EOL; 311 /* Swap addresses */ 312 inip4h->ipha_length = htons(ip_hdr_len + sizeof (*insctph) + 313 sizeof (*scch)); 314 v4addr = inip4h->ipha_src; 315 inip4h->ipha_src = inip4h->ipha_dst; 316 inip4h->ipha_dst = v4addr; 317 inip4h->ipha_ident = 0; 318 inip4h->ipha_ttl = (uchar_t)sctp_ipv4_ttl; 319 } else { 320 in6_addr_t v6addr; 321 322 inip6h = (ip6_t *)inmp->b_rptr; 323 /* Remove any extension headers assuming partial overlay */ 324 if (ip_hdr_len > IPV6_HDR_LEN) { 325 uint8_t *to; 326 327 to = inmp->b_rptr + ip_hdr_len - IPV6_HDR_LEN; 328 ovbcopy(inip6h, to, IPV6_HDR_LEN); 329 inmp->b_rptr += ip_hdr_len - IPV6_HDR_LEN; 330 ip_hdr_len = IPV6_HDR_LEN; 331 inip6h = (ip6_t *)inmp->b_rptr; 332 inip6h->ip6_nxt = IPPROTO_SCTP; 333 } 334 inip6h->ip6_plen = htons(ip_hdr_len + sizeof (*insctph) + 335 sizeof (*scch) - IPV6_HDR_LEN); 336 v6addr = inip6h->ip6_src; 337 inip6h->ip6_src = inip6h->ip6_dst; 338 inip6h->ip6_dst = v6addr; 339 inip6h->ip6_hops = (uchar_t)sctp_ipv6_hoplimit; 340 } 341 insctph = (sctp_hdr_t *)(inmp->b_rptr + ip_hdr_len); 342 343 /* Swap ports. Verification tag is reused. */ 344 port = insctph->sh_sport; 345 insctph->sh_sport = insctph->sh_dport; 346 insctph->sh_dport = port; 347 348 /* Lay in the shutdown complete chunk */ 349 scch = (sctp_chunk_hdr_t *)(insctph + 1); 350 scch->sch_id = CHUNK_SHUTDOWN_COMPLETE; 351 scch->sch_len = htons(sizeof (*scch)); 352 scch->sch_flags = 0; 353 354 /* Set the T-bit */ 355 SCTP_SET_TBIT(scch); 356 357 BUMP_LOCAL(gsctp->sctp_obchunks); 358 /* Nothing to stash... */ 359 SCTP_STASH_IPINFO(inmp, (ire_t *)NULL); 360 361 sctp_add_sendq(gsctp, inmp); 362 } 363