1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/socket.h> 34 #include <sys/protosw.h> 35 #include <sys/domain.h> 36 #include <sys/eventhandler.h> 37 #include <sys/epoch.h> 38 #include <sys/mbuf.h> 39 #include <sys/kernel.h> 40 #include <sys/lock.h> 41 #include <sys/mutex.h> 42 #include <sys/rmlock.h> 43 #include <sys/socketvar.h> 44 #include <sys/systm.h> 45 46 #include <machine/atomic.h> 47 48 #include <net/vnet.h> 49 50 struct domainhead domains = SLIST_HEAD_INITIALIZER(&domains); 51 int domain_init_status = 1; 52 static struct mtx dom_mtx; /* domain list lock */ 53 MTX_SYSINIT(domain, &dom_mtx, "domain list", MTX_DEF); 54 55 static int 56 pr_accept_notsupp(struct socket *so, struct sockaddr *sa) 57 { 58 return (EOPNOTSUPP); 59 } 60 61 static int 62 pr_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 63 { 64 return (EOPNOTSUPP); 65 } 66 67 static int 68 pr_bindat_notsupp(int fd, struct socket *so, struct sockaddr *nam, 69 struct thread *td) 70 { 71 return (EOPNOTSUPP); 72 } 73 74 static int 75 pr_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 76 { 77 return (EOPNOTSUPP); 78 } 79 80 static int 81 pr_connectat_notsupp(int fd, struct socket *so, struct sockaddr *nam, 82 struct thread *td) 83 { 84 return (EOPNOTSUPP); 85 } 86 87 static int 88 pr_connect2_notsupp(struct socket *so1, struct socket *so2) 89 { 90 return (EOPNOTSUPP); 91 } 92 93 static int 94 pr_control_notsupp(struct socket *so, u_long cmd, void *data, 95 struct ifnet *ifp, struct thread *td) 96 { 97 return (EOPNOTSUPP); 98 } 99 100 static int 101 pr_ctloutput_notsupp(struct socket *so, struct sockopt *sopt) 102 { 103 return (ENOPROTOOPT); 104 } 105 106 static int 107 pr_disconnect_notsupp(struct socket *so) 108 { 109 return (EOPNOTSUPP); 110 } 111 112 int 113 pr_listen_notsupp(struct socket *so, int backlog, struct thread *td) 114 { 115 return (EOPNOTSUPP); 116 } 117 118 static int 119 pr_peeraddr_notsupp(struct socket *so, struct sockaddr *nam) 120 { 121 return (EOPNOTSUPP); 122 } 123 124 static int 125 pr_rcvd_notsupp(struct socket *so, int flags) 126 { 127 return (EOPNOTSUPP); 128 } 129 130 static int 131 pr_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 132 { 133 return (EOPNOTSUPP); 134 } 135 136 static int 137 pr_send_notsupp(struct socket *so, int flags, struct mbuf *m, 138 struct sockaddr *addr, struct mbuf *control, struct thread *td) 139 { 140 if (control != NULL) 141 m_freem(control); 142 if ((flags & PRUS_NOTREADY) == 0) 143 m_freem(m); 144 return (EOPNOTSUPP); 145 } 146 147 static int 148 pr_sendfile_wait_notsupp(struct socket *so, off_t need, int *space) 149 { 150 return (EOPNOTSUPP); 151 } 152 153 static int 154 pr_ready_notsupp(struct socket *so, struct mbuf *m, int count) 155 { 156 return (EOPNOTSUPP); 157 } 158 159 static int 160 pr_shutdown_notsupp(struct socket *so, enum shutdown_how how) 161 { 162 return (EOPNOTSUPP); 163 } 164 165 static int 166 pr_sockaddr_notsupp(struct socket *so, struct sockaddr *nam) 167 { 168 return (EOPNOTSUPP); 169 } 170 171 static void 172 pr_init(struct domain *dom, struct protosw *pr) 173 { 174 175 KASSERT(pr->pr_attach != NULL, 176 ("%s: protocol doesn't have pr_attach", __func__)); 177 178 pr->pr_domain = dom; 179 180 #define DEFAULT(foo, bar) if (pr->foo == NULL) pr->foo = bar 181 DEFAULT(pr_sosend, sosend_generic); 182 DEFAULT(pr_soreceive, soreceive_generic); 183 DEFAULT(pr_sopoll, sopoll_generic); 184 DEFAULT(pr_setsbopt, sbsetopt); 185 DEFAULT(pr_aio_queue, soaio_queue_generic); 186 DEFAULT(pr_kqfilter, sokqfilter_generic); 187 188 #define NOTSUPP(foo) if (pr->foo == NULL) pr->foo = foo ## _notsupp 189 NOTSUPP(pr_accept); 190 NOTSUPP(pr_bind); 191 NOTSUPP(pr_bindat); 192 NOTSUPP(pr_connect); 193 NOTSUPP(pr_connect2); 194 NOTSUPP(pr_connectat); 195 NOTSUPP(pr_control); 196 NOTSUPP(pr_ctloutput); 197 NOTSUPP(pr_disconnect); 198 NOTSUPP(pr_listen); 199 NOTSUPP(pr_peeraddr); 200 NOTSUPP(pr_rcvd); 201 NOTSUPP(pr_rcvoob); 202 NOTSUPP(pr_send); 203 NOTSUPP(pr_sendfile_wait); 204 NOTSUPP(pr_shutdown); 205 NOTSUPP(pr_sockaddr); 206 NOTSUPP(pr_ready); 207 } 208 209 /* 210 * Add a new protocol domain to the list of supported domains 211 * Note: you can't unload it again because a socket may be using it. 212 * XXX can't fail at this time. 213 */ 214 void 215 domain_add(struct domain *dp) 216 { 217 struct protosw *pr; 218 219 MPASS(IS_DEFAULT_VNET(curvnet)); 220 221 if (dp->dom_probe != NULL && (*dp->dom_probe)() != 0) 222 return; 223 224 for (int i = 0; i < dp->dom_nprotosw; i++) 225 if ((pr = dp->dom_protosw[i]) != NULL) 226 pr_init(dp, pr); 227 228 mtx_lock(&dom_mtx); 229 #ifdef INVARIANTS 230 struct domain *tmp; 231 SLIST_FOREACH(tmp, &domains, dom_next) 232 MPASS(tmp->dom_family != dp->dom_family); 233 #endif 234 SLIST_INSERT_HEAD(&domains, dp, dom_next); 235 mtx_unlock(&dom_mtx); 236 } 237 238 void 239 domain_remove(struct domain *dp) 240 { 241 242 if ((dp->dom_flags & DOMF_UNLOADABLE) == 0) 243 return; 244 245 mtx_lock(&dom_mtx); 246 SLIST_REMOVE(&domains, dp, domain, dom_next); 247 mtx_unlock(&dom_mtx); 248 } 249 250 static void 251 domainfinalize(void *dummy) 252 { 253 254 mtx_lock(&dom_mtx); 255 KASSERT(domain_init_status == 1, ("domainfinalize called too late!")); 256 domain_init_status = 2; 257 mtx_unlock(&dom_mtx); 258 } 259 SYSINIT(domainfin, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST, domainfinalize, 260 NULL); 261 262 struct domain * 263 pffinddomain(int family) 264 { 265 struct domain *dp; 266 267 SLIST_FOREACH(dp, &domains, dom_next) 268 if (dp->dom_family == family) 269 return (dp); 270 return (NULL); 271 } 272 273 struct protosw * 274 pffindproto(int family, int type, int proto) 275 { 276 struct domain *dp; 277 struct protosw *pr; 278 279 dp = pffinddomain(family); 280 if (dp == NULL) 281 return (NULL); 282 283 for (int i = 0; i < dp->dom_nprotosw; i++) 284 if ((pr = dp->dom_protosw[i]) != NULL && pr->pr_type == type && 285 (pr->pr_protocol == 0 || proto == 0 || 286 pr->pr_protocol == proto)) 287 return (pr); 288 289 return (NULL); 290 } 291 292 /* 293 * The caller must make sure that the new protocol is fully set up and ready to 294 * accept requests before it is registered. 295 */ 296 int 297 protosw_register(struct domain *dp, struct protosw *npr) 298 { 299 struct protosw **prp; 300 301 MPASS(dp); 302 MPASS(npr && npr->pr_type > 0 && npr->pr_protocol > 0); 303 304 prp = NULL; 305 /* 306 * Protect us against races when two protocol registrations for 307 * the same protocol happen at the same time. 308 */ 309 mtx_lock(&dom_mtx); 310 for (int i = 0; i < dp->dom_nprotosw; i++) { 311 if (dp->dom_protosw[i] == NULL) { 312 /* Remember the first free spacer. */ 313 if (prp == NULL) 314 prp = &dp->dom_protosw[i]; 315 } else { 316 /* 317 * The new protocol must not yet exist. 318 * XXXAO: Check only protocol? 319 * XXXGL: Maybe assert that it doesn't exist? 320 */ 321 if ((dp->dom_protosw[i]->pr_type == npr->pr_type) && 322 (dp->dom_protosw[i]->pr_protocol == 323 npr->pr_protocol)) { 324 mtx_unlock(&dom_mtx); 325 return (EEXIST); 326 } 327 328 } 329 } 330 331 /* If no free spacer is found we can't add the new protocol. */ 332 if (prp == NULL) { 333 mtx_unlock(&dom_mtx); 334 return (ENOMEM); 335 } 336 337 pr_init(dp, npr); 338 *prp = npr; 339 mtx_unlock(&dom_mtx); 340 341 return (0); 342 } 343 344 /* 345 * The caller must make sure the protocol and its functions correctly shut down 346 * all sockets and release all locks and memory references. 347 */ 348 int 349 protosw_unregister(struct protosw *pr) 350 { 351 struct domain *dp; 352 struct protosw **prp; 353 354 dp = pr->pr_domain; 355 prp = NULL; 356 357 mtx_lock(&dom_mtx); 358 /* The protocol must exist and only once. */ 359 for (int i = 0; i < dp->dom_nprotosw; i++) { 360 if (dp->dom_protosw[i] == pr) { 361 KASSERT(prp == NULL, 362 ("%s: domain %p protocol %p registered twice\n", 363 __func__, dp, pr)); 364 prp = &dp->dom_protosw[i]; 365 } 366 } 367 368 /* Protocol does not exist. XXXGL: assert that it does? */ 369 if (prp == NULL) { 370 mtx_unlock(&dom_mtx); 371 return (EPROTONOSUPPORT); 372 } 373 374 /* De-orbit the protocol and make the slot available again. */ 375 *prp = NULL; 376 mtx_unlock(&dom_mtx); 377 378 return (0); 379 } 380