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 * @(#)uipc_domain.c 8.2 (Berkeley) 10/18/93 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/socket.h> 39 #include <sys/protosw.h> 40 #include <sys/domain.h> 41 #include <sys/eventhandler.h> 42 #include <sys/epoch.h> 43 #include <sys/mbuf.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/mutex.h> 47 #include <sys/rmlock.h> 48 #include <sys/socketvar.h> 49 #include <sys/systm.h> 50 51 #include <machine/atomic.h> 52 53 #include <net/vnet.h> 54 55 struct domainhead domains = SLIST_HEAD_INITIALIZER(&domains); 56 int domain_init_status = 1; 57 static struct mtx dom_mtx; /* domain list lock */ 58 MTX_SYSINIT(domain, &dom_mtx, "domain list", MTX_DEF); 59 60 static int 61 pr_accept_notsupp(struct socket *so, struct sockaddr **nam) 62 { 63 return (EOPNOTSUPP); 64 } 65 66 static int 67 pr_aio_queue_notsupp(struct socket *so, struct kaiocb *job) 68 { 69 return (EOPNOTSUPP); 70 } 71 72 static int 73 pr_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 74 { 75 return (EOPNOTSUPP); 76 } 77 78 static int 79 pr_bindat_notsupp(int fd, struct socket *so, struct sockaddr *nam, 80 struct thread *td) 81 { 82 return (EOPNOTSUPP); 83 } 84 85 static int 86 pr_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 87 { 88 return (EOPNOTSUPP); 89 } 90 91 static int 92 pr_connectat_notsupp(int fd, struct socket *so, struct sockaddr *nam, 93 struct thread *td) 94 { 95 return (EOPNOTSUPP); 96 } 97 98 static int 99 pr_connect2_notsupp(struct socket *so1, struct socket *so2) 100 { 101 return (EOPNOTSUPP); 102 } 103 104 static int 105 pr_control_notsupp(struct socket *so, u_long cmd, void *data, 106 struct ifnet *ifp, struct thread *td) 107 { 108 return (EOPNOTSUPP); 109 } 110 111 static int 112 pr_disconnect_notsupp(struct socket *so) 113 { 114 return (EOPNOTSUPP); 115 } 116 117 static int 118 pr_listen_notsupp(struct socket *so, int backlog, struct thread *td) 119 { 120 return (EOPNOTSUPP); 121 } 122 123 static int 124 pr_peeraddr_notsupp(struct socket *so, struct sockaddr **nam) 125 { 126 return (EOPNOTSUPP); 127 } 128 129 static int 130 pr_rcvd_notsupp(struct socket *so, int flags) 131 { 132 return (EOPNOTSUPP); 133 } 134 135 static int 136 pr_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 137 { 138 return (EOPNOTSUPP); 139 } 140 141 static int 142 pr_send_notsupp(struct socket *so, int flags, struct mbuf *m, 143 struct sockaddr *addr, struct mbuf *control, struct thread *td) 144 { 145 if (control != NULL) 146 m_freem(control); 147 if ((flags & PRUS_NOTREADY) == 0) 148 m_freem(m); 149 return (EOPNOTSUPP); 150 } 151 152 static int 153 pr_ready_notsupp(struct socket *so, struct mbuf *m, int count) 154 { 155 return (EOPNOTSUPP); 156 } 157 158 static int 159 pr_shutdown_notsupp(struct socket *so) 160 { 161 return (EOPNOTSUPP); 162 } 163 164 static int 165 pr_sockaddr_notsupp(struct socket *so, struct sockaddr **nam) 166 { 167 return (EOPNOTSUPP); 168 } 169 170 static int 171 pr_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio, 172 struct mbuf *top, struct mbuf *control, int flags, struct thread *td) 173 { 174 return (EOPNOTSUPP); 175 } 176 177 static int 178 pr_soreceive_notsupp(struct socket *so, struct sockaddr **paddr, 179 struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 180 { 181 return (EOPNOTSUPP); 182 } 183 184 static int 185 pr_sopoll_notsupp(struct socket *so, int events, struct ucred *cred, 186 struct thread *td) 187 { 188 return (EOPNOTSUPP); 189 } 190 191 static void 192 pr_init(struct domain *dom, struct protosw *pr) 193 { 194 195 KASSERT(pr->pr_attach != NULL, 196 ("%s: protocol doesn't have pr_attach", __func__)); 197 198 pr->pr_domain = dom; 199 200 #define DEFAULT(foo, bar) if (pr->foo == NULL) pr->foo = bar 201 DEFAULT(pr_sosend, sosend_generic); 202 DEFAULT(pr_soreceive, soreceive_generic); 203 DEFAULT(pr_sopoll, sopoll_generic); 204 205 #define NOTSUPP(foo) if (pr->foo == NULL) pr->foo = foo ## _notsupp 206 NOTSUPP(pr_accept); 207 NOTSUPP(pr_aio_queue); 208 NOTSUPP(pr_bind); 209 NOTSUPP(pr_bindat); 210 NOTSUPP(pr_connect); 211 NOTSUPP(pr_connect2); 212 NOTSUPP(pr_connectat); 213 NOTSUPP(pr_control); 214 NOTSUPP(pr_disconnect); 215 NOTSUPP(pr_listen); 216 NOTSUPP(pr_peeraddr); 217 NOTSUPP(pr_rcvd); 218 NOTSUPP(pr_rcvoob); 219 NOTSUPP(pr_send); 220 NOTSUPP(pr_shutdown); 221 NOTSUPP(pr_sockaddr); 222 NOTSUPP(pr_sosend); 223 NOTSUPP(pr_soreceive); 224 NOTSUPP(pr_sopoll); 225 NOTSUPP(pr_ready); 226 } 227 228 /* 229 * Add a new protocol domain to the list of supported domains 230 * Note: you cant unload it again because a socket may be using it. 231 * XXX can't fail at this time. 232 */ 233 void 234 domain_add(struct domain *dp) 235 { 236 struct protosw *pr; 237 238 MPASS(IS_DEFAULT_VNET(curvnet)); 239 240 if (dp->dom_probe != NULL && (*dp->dom_probe)() != 0) 241 return; 242 243 for (int i = 0; i < dp->dom_nprotosw; i++) 244 if ((pr = dp->dom_protosw[i]) != NULL) 245 pr_init(dp, pr); 246 247 mtx_lock(&dom_mtx); 248 #ifdef INVARIANTS 249 struct domain *tmp; 250 SLIST_FOREACH(tmp, &domains, dom_next) 251 MPASS(tmp->dom_family != dp->dom_family); 252 #endif 253 SLIST_INSERT_HEAD(&domains, dp, dom_next); 254 mtx_unlock(&dom_mtx); 255 } 256 257 void 258 domain_remove(struct domain *dp) 259 { 260 261 if ((dp->dom_flags & DOMF_UNLOADABLE) == 0) 262 return; 263 264 mtx_lock(&dom_mtx); 265 SLIST_REMOVE(&domains, dp, domain, dom_next); 266 mtx_unlock(&dom_mtx); 267 } 268 269 static void 270 domainfinalize(void *dummy) 271 { 272 273 mtx_lock(&dom_mtx); 274 KASSERT(domain_init_status == 1, ("domainfinalize called too late!")); 275 domain_init_status = 2; 276 mtx_unlock(&dom_mtx); 277 } 278 SYSINIT(domainfin, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST, domainfinalize, 279 NULL); 280 281 struct domain * 282 pffinddomain(int family) 283 { 284 struct domain *dp; 285 286 SLIST_FOREACH(dp, &domains, dom_next) 287 if (dp->dom_family == family) 288 return (dp); 289 return (NULL); 290 } 291 292 struct protosw * 293 pffindproto(int family, int type, int proto) 294 { 295 struct domain *dp; 296 struct protosw *pr; 297 298 dp = pffinddomain(family); 299 if (dp == NULL) 300 return (NULL); 301 302 for (int i = 0; i < dp->dom_nprotosw; i++) 303 if ((pr = dp->dom_protosw[i]) != NULL && pr->pr_type == type && 304 (pr->pr_protocol == 0 || proto == 0 || 305 pr->pr_protocol == proto)) 306 return (pr); 307 308 return (NULL); 309 } 310 311 /* 312 * The caller must make sure that the new protocol is fully set up and ready to 313 * accept requests before it is registered. 314 */ 315 int 316 protosw_register(struct domain *dp, struct protosw *npr) 317 { 318 struct protosw **prp; 319 320 MPASS(dp); 321 MPASS(npr && npr->pr_type > 0 && npr->pr_protocol > 0); 322 323 prp = NULL; 324 /* 325 * Protect us against races when two protocol registrations for 326 * the same protocol happen at the same time. 327 */ 328 mtx_lock(&dom_mtx); 329 for (int i = 0; i < dp->dom_nprotosw; i++) { 330 if (dp->dom_protosw[i] == NULL) { 331 /* Remember the first free spacer. */ 332 if (prp == NULL) 333 prp = &dp->dom_protosw[i]; 334 } else { 335 /* 336 * The new protocol must not yet exist. 337 * XXXAO: Check only protocol? 338 * XXXGL: Maybe assert that it doesn't exist? 339 */ 340 if ((dp->dom_protosw[i]->pr_type == npr->pr_type) && 341 (dp->dom_protosw[i]->pr_protocol == 342 npr->pr_protocol)) { 343 mtx_unlock(&dom_mtx); 344 return (EEXIST); 345 } 346 347 } 348 } 349 350 /* If no free spacer is found we can't add the new protocol. */ 351 if (prp == NULL) { 352 mtx_unlock(&dom_mtx); 353 return (ENOMEM); 354 } 355 356 pr_init(dp, npr); 357 *prp = npr; 358 mtx_unlock(&dom_mtx); 359 360 return (0); 361 } 362 363 /* 364 * The caller must make sure the protocol and its functions correctly shut down 365 * all sockets and release all locks and memory references. 366 */ 367 int 368 protosw_unregister(struct protosw *pr) 369 { 370 struct domain *dp; 371 struct protosw **prp; 372 373 dp = pr->pr_domain; 374 prp = NULL; 375 376 mtx_lock(&dom_mtx); 377 /* The protocol must exist and only once. */ 378 for (int i = 0; i < dp->dom_nprotosw; i++) { 379 if (dp->dom_protosw[i] == pr) { 380 KASSERT(prp == NULL, 381 ("%s: domain %p protocol %p registered twice\n", 382 __func__, dp, pr)); 383 prp = &dp->dom_protosw[i]; 384 } 385 } 386 387 /* Protocol does not exist. XXXGL: assert that it does? */ 388 if (prp == NULL) { 389 mtx_unlock(&dom_mtx); 390 return (EPROTONOSUPPORT); 391 } 392 393 /* De-orbit the protocol and make the slot available again. */ 394 *prp = NULL; 395 mtx_unlock(&dom_mtx); 396 397 return (0); 398 } 399