1 /* $NetBSD: link_proto.c,v 1.5 2008/11/07 00:20:13 dyoung Exp $ */ 2 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_proto.c 8.2 (Berkeley) 2/14/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: link_proto.c,v 1.5 2008/11/07 00:20:13 dyoung Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/socket.h> 39 #include <sys/protosw.h> 40 #include <sys/domain.h> 41 #include <sys/mbuf.h> 42 #include <sys/un.h> 43 #include <sys/socketvar.h> 44 45 #include <net/if.h> 46 #include <net/if_dl.h> 47 #include <net/raw_cb.h> 48 #include <net/route.h> 49 50 static int sockaddr_dl_cmp(const struct sockaddr *, const struct sockaddr *); 51 static int link_usrreq(struct socket *, int, struct mbuf *, struct mbuf *, 52 struct mbuf *, struct lwp *); 53 static void link_init(void); 54 55 /* 56 * Definitions of protocols supported in the link-layer domain. 57 */ 58 59 DOMAIN_DEFINE(linkdomain); /* forward define and add to link set */ 60 61 const struct protosw linksw[] = { 62 { .pr_type = SOCK_DGRAM, 63 .pr_domain = &linkdomain, 64 .pr_protocol = 0, /* XXX */ 65 .pr_flags = PR_ATOMIC|PR_ADDR|PR_PURGEIF, 66 .pr_input = NULL, 67 .pr_ctlinput = NULL, 68 .pr_ctloutput = NULL, 69 .pr_usrreq = link_usrreq, 70 .pr_init = link_init, 71 }, 72 }; 73 74 struct domain linkdomain = { 75 .dom_family = AF_LINK, 76 .dom_name = "link", 77 .dom_externalize = NULL, 78 .dom_dispose = NULL, 79 .dom_protosw = linksw, 80 .dom_protoswNPROTOSW = &linksw[__arraycount(linksw)], 81 .dom_sockaddr_cmp = sockaddr_dl_cmp 82 }; 83 84 static void 85 link_init(void) 86 { 87 return; 88 } 89 90 static int 91 link_control(struct socket *so, unsigned long cmd, void *data, 92 struct ifnet *ifp, struct lwp *l) 93 { 94 int error, s; 95 bool isactive, mkactive; 96 struct if_laddrreq *iflr; 97 union { 98 struct sockaddr sa; 99 struct sockaddr_dl sdl; 100 struct sockaddr_storage ss; 101 } u; 102 struct ifaddr *ifa; 103 const struct sockaddr_dl *asdl, *nsdl; 104 105 switch (cmd) { 106 case SIOCALIFADDR: 107 case SIOCDLIFADDR: 108 case SIOCGLIFADDR: 109 iflr = data; 110 111 if (iflr->addr.ss_family != AF_LINK) 112 return EINVAL; 113 114 asdl = satocsdl(sstocsa(&iflr->addr)); 115 116 if (asdl->sdl_alen != ifp->if_addrlen) 117 return EINVAL; 118 119 if (sockaddr_dl_init(&u.sdl, sizeof(u.ss), ifp->if_index, 120 ifp->if_type, ifp->if_xname, strlen(ifp->if_xname), 121 CLLADDR(asdl), asdl->sdl_alen) == NULL) 122 return EINVAL; 123 124 if ((iflr->flags & IFLR_PREFIX) == 0) 125 ; 126 else if (iflr->prefixlen != NBBY * ifp->if_addrlen) 127 return EINVAL; /* XXX match with prefix */ 128 129 error = 0; 130 131 s = splnet(); 132 133 IFADDR_FOREACH(ifa, ifp) { 134 if (sockaddr_cmp(&u.sa, ifa->ifa_addr) == 0) 135 break; 136 } 137 138 switch (cmd) { 139 case SIOCGLIFADDR: 140 if ((iflr->flags & IFLR_PREFIX) == 0) { 141 IFADDR_FOREACH(ifa, ifp) { 142 if (ifa->ifa_addr->sa_family == AF_LINK) 143 break; 144 } 145 } 146 if (ifa == NULL) { 147 error = EADDRNOTAVAIL; 148 break; 149 } 150 151 if (ifa == ifp->if_dl) 152 iflr->flags = IFLR_ACTIVE; 153 else 154 iflr->flags = 0; 155 156 if (ifa == ifp->if_hwdl) 157 iflr->flags |= IFLR_FACTORY; 158 159 sockaddr_copy(sstosa(&iflr->addr), sizeof(iflr->addr), 160 ifa->ifa_addr); 161 162 break; 163 case SIOCDLIFADDR: 164 if (ifa == NULL) 165 error = EADDRNOTAVAIL; 166 else if (ifa == ifp->if_dl || ifa == ifp->if_hwdl) 167 error = EBUSY; 168 else { 169 /* TBD routing socket */ 170 rt_newaddrmsg(RTM_DELETE, ifa, 0, NULL); 171 ifa_remove(ifp, ifa); 172 } 173 break; 174 case SIOCALIFADDR: 175 if (ifa != NULL) 176 ; 177 else if ((ifa = if_dl_create(ifp, &nsdl)) == NULL) { 178 error = ENOMEM; 179 break; 180 } else { 181 sockaddr_copy(ifa->ifa_addr, 182 ifa->ifa_addr->sa_len, &u.sa); 183 ifa_insert(ifp, ifa); 184 rt_newaddrmsg(RTM_ADD, ifa, 0, NULL); 185 } 186 187 mkactive = (iflr->flags & IFLR_ACTIVE) != 0; 188 isactive = (ifa == ifp->if_dl); 189 190 if (!isactive && mkactive) { 191 if_activate_sadl(ifp, ifa, nsdl); 192 error = ENETRESET; 193 } 194 break; 195 } 196 splx(s); 197 if (error != ENETRESET) 198 return error; 199 else if ((ifp->if_flags & IFF_RUNNING) != 0) 200 return (*ifp->if_init)(ifp); 201 else 202 return 0; 203 default: 204 return ENOTTY; 205 } 206 } 207 208 static int 209 link_usrreq(struct socket *so, int req, struct mbuf *m, struct mbuf *nam, 210 struct mbuf *control, struct lwp *l) 211 { 212 switch (req) { 213 case PRU_ATTACH: 214 sosetlock(so); 215 return 0; 216 case PRU_DETACH: 217 sofree(so); 218 return 0; 219 case PRU_CONTROL: 220 return link_control(so, (unsigned long)m, nam, 221 (struct ifnet *)control, l); 222 default: 223 return EOPNOTSUPP; 224 } 225 } 226 227 /* Compare the field at byte offsets [fieldstart, fieldend) in 228 * two memory regions, [l, l + llen) and [r, r + llen). 229 */ 230 static inline int 231 submemcmp(const void *l, const void *r, 232 const uint_fast8_t llen, const uint_fast8_t rlen, 233 const uint_fast8_t fieldstart, const uint_fast8_t fieldend) 234 { 235 uint_fast8_t cmpend, minlen; 236 const uint8_t *lb = l, *rb = r; 237 int rc; 238 239 minlen = MIN(llen, rlen); 240 241 /* The field is missing from one region. The shorter region is the 242 * lesser region. 243 */ 244 if (fieldstart >= minlen) 245 return llen - rlen; 246 247 /* Two empty, present fields are always equal. */ 248 if (fieldstart > fieldend) 249 return 0; 250 251 cmpend = MIN(fieldend, minlen); 252 253 rc = memcmp(&lb[fieldstart], &rb[fieldstart], cmpend - fieldstart); 254 255 if (rc != 0) 256 return rc; 257 /* If one or both fields are truncated, then the shorter is the lesser 258 * field. 259 */ 260 if (minlen < fieldend) 261 return llen - rlen; 262 /* Fields are full-length and equal. The fields are equal. */ 263 return 0; 264 } 265 266 uint8_t 267 sockaddr_dl_measure(uint8_t namelen, uint8_t addrlen) 268 { 269 return offsetof(struct sockaddr_dl, sdl_data[namelen + addrlen]); 270 } 271 272 struct sockaddr * 273 sockaddr_dl_alloc(uint16_t ifindex, uint8_t type, 274 const void *name, uint8_t namelen, const void *addr, uint8_t addrlen, 275 int flags) 276 { 277 struct sockaddr *sa; 278 socklen_t len; 279 280 len = sockaddr_dl_measure(namelen, addrlen); 281 sa = sockaddr_alloc(AF_LINK, len, flags); 282 283 if (sa == NULL) 284 return NULL; 285 286 if (sockaddr_dl_init(satosdl(sa), len, ifindex, type, name, namelen, 287 addr, addrlen) == NULL) { 288 sockaddr_free(sa); 289 return NULL; 290 } 291 292 return sa; 293 } 294 295 struct sockaddr_dl * 296 sockaddr_dl_init(struct sockaddr_dl *sdl, socklen_t socklen, uint16_t ifindex, 297 uint8_t type, const void *name, uint8_t namelen, const void *addr, 298 uint8_t addrlen) 299 { 300 socklen_t len; 301 302 sdl->sdl_family = AF_LINK; 303 sdl->sdl_slen = 0; 304 len = sockaddr_dl_measure(namelen, addrlen); 305 if (len > socklen) { 306 sdl->sdl_len = socklen; 307 #ifdef DIAGNOSTIC 308 printf("%s: too long: %" PRIu8 " > %" PRIu8 "\n", __func__, len, 309 socklen); 310 #endif 311 return NULL; 312 } 313 sdl->sdl_len = len; 314 sdl->sdl_index = ifindex; 315 sdl->sdl_type = type; 316 memset(&sdl->sdl_data[0], 0, namelen + addrlen); 317 if (name != NULL) { 318 memcpy(&sdl->sdl_data[0], name, namelen); 319 sdl->sdl_nlen = namelen; 320 } else 321 sdl->sdl_nlen = 0; 322 if (addr != NULL) { 323 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 324 sdl->sdl_alen = addrlen; 325 } else 326 sdl->sdl_alen = 0; 327 return sdl; 328 } 329 330 static int 331 sockaddr_dl_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2) 332 { 333 int rc; 334 const uint_fast8_t indexofs = offsetof(struct sockaddr_dl, sdl_index); 335 const uint_fast8_t nlenofs = offsetof(struct sockaddr_dl, sdl_nlen); 336 uint_fast8_t dataofs = offsetof(struct sockaddr_dl, sdl_data[0]); 337 const struct sockaddr_dl *sdl1, *sdl2; 338 339 sdl1 = satocsdl(sa1); 340 sdl2 = satocsdl(sa2); 341 342 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 343 indexofs, nlenofs); 344 345 if (rc != 0) 346 return rc; 347 348 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 349 dataofs, dataofs + MIN(sdl1->sdl_nlen, sdl2->sdl_nlen)); 350 351 if (rc != 0) 352 return rc; 353 354 if (sdl1->sdl_nlen != sdl2->sdl_nlen) 355 return sdl1->sdl_nlen - sdl2->sdl_nlen; 356 357 dataofs += sdl1->sdl_nlen; 358 359 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 360 dataofs, dataofs + MIN(sdl1->sdl_alen, sdl2->sdl_alen)); 361 362 if (rc != 0) 363 return rc; 364 365 if (sdl1->sdl_alen != sdl2->sdl_alen) 366 return sdl1->sdl_alen - sdl2->sdl_alen; 367 368 dataofs += sdl1->sdl_alen; 369 370 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 371 dataofs, dataofs + MIN(sdl1->sdl_slen, sdl2->sdl_slen)); 372 373 if (sdl1->sdl_slen != sdl2->sdl_slen) 374 return sdl1->sdl_slen - sdl2->sdl_slen; 375 376 return sdl1->sdl_len - sdl2->sdl_len; 377 } 378 379 struct sockaddr_dl * 380 sockaddr_dl_setaddr(struct sockaddr_dl *sdl, socklen_t socklen, 381 const void *addr, uint8_t addrlen) 382 { 383 socklen_t len; 384 385 len = sockaddr_dl_measure(sdl->sdl_nlen, addrlen); 386 if (len > socklen) { 387 #ifdef DIAGNOSTIC 388 printf("%s: too long: %" PRIu8 " > %" PRIu8 "\n", __func__, len, 389 socklen); 390 #endif 391 return NULL; 392 } 393 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 394 sdl->sdl_alen = addrlen; 395 sdl->sdl_len = len; 396 return sdl; 397 } 398