1 /* $NetBSD: if_srt.c,v 1.27 2017/10/23 09:32:55 msaitoh Exp $ */ 2 /* This file is in the public domain. */ 3 4 #include <sys/cdefs.h> 5 __KERNEL_RCSID(0, "$NetBSD: if_srt.c,v 1.27 2017/10/23 09:32:55 msaitoh Exp $"); 6 7 #ifdef _KERNEL_OPT 8 #include "opt_inet.h" 9 #endif 10 11 #if !defined(INET) && !defined(INET6) 12 #error "srt without INET/INET6?" 13 #endif 14 15 #ifndef SRT_MAXUNIT 16 #define SRT_MAXUNIT 255 17 #endif 18 19 /* include-file bug workarounds */ 20 #include <sys/types.h> /* sys/conf.h */ 21 #include <sys/resource.h> /* sys/resourcevar.h 22 * (uvm/uvm_param.h, sys/mbuf.h) 23 */ 24 #include <netinet/in.h> /* netinet/ip.h */ 25 #include <sys/param.h> /* sys/mbuf.h */ 26 #include <netinet/in_systm.h> /* netinet/ip.h */ 27 28 #include <sys/conf.h> 29 #include <sys/mbuf.h> 30 #include <sys/errno.h> 31 #include <sys/fcntl.h> 32 #include <sys/param.h> 33 #include <sys/ioctl.h> 34 #include <sys/module.h> 35 #include <sys/device.h> 36 #include <netinet/ip.h> 37 #include <netinet/ip6.h> 38 #include <netinet6/in6_var.h> 39 #include <netinet6/ip6_var.h> 40 #include <netinet6/nd6.h> 41 #include <netinet6/scope6_var.h> 42 #include <net/if_types.h> 43 44 #include "if_srt.h" 45 46 /* until we know what to pass to bpfattach.... */ 47 /* #define BPFILTER_NOW_AVAILABLE */ 48 49 struct srt_softc { 50 struct ifnet intf; /* XXX interface botch */ 51 int unit; 52 int nrt; 53 struct srt_rt **rts; 54 unsigned int flags; /* SSF_* values from if_srt.h */ 55 #define SSF_UCHG (SSF_MTULOCK) /* userland-changeable bits */ 56 unsigned int kflags; /* bits private to this file */ 57 #define SKF_CDEVOPEN 0x00000001 58 }; 59 60 #include "ioconf.h" 61 62 static struct srt_softc *softcv[SRT_MAXUNIT+1]; 63 static unsigned int global_flags; 64 65 static u_int srt_count; 66 67 /* Internal routines. */ 68 69 static unsigned int ipv4_masks[33] = { 70 0x00000000, /* /0 */ 71 0x80000000, 0xc0000000, 0xe0000000, 0xf0000000, /* /1 - /4 */ 72 0xf8000000, 0xfc000000, 0xfe000000, 0xff000000, /* /5 - /8 */ 73 0xff800000, 0xffc00000, 0xffe00000, 0xfff00000, /* /9 - /12 */ 74 0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000, /* /13 - /16 */ 75 0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000, /* /17 - /20 */ 76 0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00, /* /21 - /24 */ 77 0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0, /* /25 - /28 */ 78 0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff /* /29 - /32 */ 79 }; 80 81 static void 82 update_mtu(struct srt_softc *sc) 83 { 84 int mtu; 85 int i; 86 struct srt_rt *r; 87 88 if (sc->flags & SSF_MTULOCK) 89 return; 90 mtu = 65535; 91 for (i = sc->nrt-1; i>=0; i--) { 92 r = sc->rts[i]; 93 if (r->u.dstifp->if_mtu < mtu) 94 mtu = r->u.dstifp->if_mtu; 95 } 96 sc->intf.if_mtu = mtu; 97 } 98 99 static struct srt_rt * 100 find_rt(struct srt_softc *sc, int af, ...) 101 { 102 int i; 103 struct srt_rt *r; 104 struct in_addr ia; 105 struct in6_addr ia6; 106 va_list ap; 107 108 ia.s_addr = 0; ia6.s6_addr[0] = 0; /* shut up incorrect -Wuninitialized */ 109 va_start(ap,af); 110 switch (af) { 111 case AF_INET: 112 ia = va_arg(ap,struct in_addr); 113 break; 114 case AF_INET6: 115 ia6 = va_arg(ap,struct in6_addr); 116 break; 117 default: 118 panic("if_srt find_rt: impossible address family"); 119 break; 120 } 121 va_end(ap); 122 for (i=0; i < sc->nrt; i++) { 123 r = sc->rts[i]; 124 if (r->af != af) 125 continue; 126 switch (af) { 127 case AF_INET: 128 if ((ia.s_addr & htonl(ipv4_masks[r->srcmask])) == 129 r->srcmatch.v4.s_addr) 130 return r; 131 break; 132 case AF_INET6: 133 if ((r->srcmask >= 8) && 134 memcmp(&ia6,&r->srcmatch.v6,r->srcmask / 8) != 0) 135 continue; 136 if ((r->srcmask % 8) && 137 ((ia6.s6_addr[r->srcmask / 8] ^ 138 r->srcmatch.v6.s6_addr[r->srcmask / 8]) & 139 0xff & (0xff00 >> (r->srcmask % 8)))) 140 continue; 141 return r; 142 default: 143 panic("if_srt find_rt: impossible address family 2"); 144 break; 145 } 146 } 147 return 0; 148 } 149 150 /* Network device interface. */ 151 152 static int 153 srt_if_ioctl(struct ifnet *ifp, u_long cmd, void *data) 154 { 155 struct ifaddr *ifa; 156 int s; 157 int err; 158 159 err = 0; 160 s = splnet(); 161 switch (cmd) { 162 case SIOCINITIFADDR: 163 ifa = (void *) data; 164 switch (ifa->ifa_addr->sa_family) { 165 #ifdef INET 166 case AF_INET: 167 break; 168 #endif 169 #ifdef INET6 170 case AF_INET6: 171 break; 172 #endif 173 default: 174 err = EAFNOSUPPORT; 175 break; 176 } 177 break; 178 default: 179 if ((err = ifioctl_common(ifp, cmd, data)) == ENETRESET) 180 err = 0; 181 break; 182 } 183 splx(s); 184 return err; 185 } 186 187 static int 188 srt_if_output( 189 struct ifnet *ifp, 190 struct mbuf *m, 191 const struct sockaddr *to, 192 const struct rtentry *rtp) 193 { 194 struct srt_softc *sc; 195 struct srt_rt *r; 196 197 sc = ifp->if_softc; 198 if (! (ifp->if_flags & IFF_UP)) { 199 m_freem(m); 200 return ENETDOWN; 201 } 202 switch (to->sa_family) { 203 #ifdef INET 204 case AF_INET: { 205 struct ip *ip; 206 ip = mtod(m,struct ip *); 207 r = find_rt(sc,AF_INET,ip->ip_src); 208 break; 209 } 210 #endif 211 #ifdef INET6 212 case AF_INET6: { 213 struct ip6_hdr *ip; 214 ip = mtod(m,struct ip6_hdr *); 215 r = find_rt(sc,AF_INET6,ip->ip6_src); 216 break; 217 } 218 #endif 219 default: 220 IF_DROP(&ifp->if_snd); 221 m_freem(m); 222 return EAFNOSUPPORT; 223 } 224 /* XXX Do we need to bpf_tap? Or do higher layers now handle that? */ 225 /* if_gif.c seems to imply the latter. */ 226 ifp->if_opackets ++; 227 if (! r) { 228 ifp->if_oerrors ++; 229 m_freem(m); 230 return 0; 231 } 232 if (! (m->m_flags & M_PKTHDR)) { 233 printf("srt_if_output no PKTHDR\n"); 234 m_freem(m); 235 return 0; 236 } 237 ifp->if_obytes += m->m_pkthdr.len; 238 if (! (r->u.dstifp->if_flags & IFF_UP)) { 239 m_freem(m); 240 return 0; /* XXX ENETDOWN? */ 241 } 242 /* XXX is 0 the right last arg here? */ 243 if (to->sa_family == AF_INET6) 244 return ip6_if_output(r->u.dstifp, r->u.dstifp, m, &r->dst.sin6, 0); 245 return if_output_lock(r->u.dstifp, r->u.dstifp, m, &r->dst.sa, 0); 246 } 247 248 static int 249 srt_clone_create(struct if_clone *cl, int unit) 250 { 251 struct srt_softc *sc; 252 int rv; 253 254 if (unit < 0 || unit > SRT_MAXUNIT) 255 return ENXIO; 256 if (softcv[unit]) 257 return EBUSY; 258 sc = malloc(sizeof(struct srt_softc), M_DEVBUF, M_WAITOK | M_ZERO); 259 sc->unit = unit; 260 sc->nrt = 0; 261 sc->rts = 0; 262 sc->flags = 0; 263 sc->kflags = 0; 264 if_initname(&sc->intf,cl->ifc_name,unit); 265 sc->intf.if_softc = sc; 266 sc->intf.if_mtu = 65535; 267 sc->intf.if_flags = IFF_POINTOPOINT; 268 sc->intf.if_type = IFT_OTHER; 269 sc->intf.if_ioctl = &srt_if_ioctl; 270 sc->intf.if_output = &srt_if_output; 271 sc->intf.if_dlt = DLT_RAW; 272 rv = if_attach(&sc->intf); 273 if (rv != 0) { 274 aprint_error("%s: if_initialize failed(%d)\n", 275 sc->intf.if_xname, rv); 276 free(sc, M_DEVBUF); 277 return rv; 278 } 279 if_alloc_sadl(&sc->intf); 280 #ifdef BPFILTER_NOW_AVAILABLE 281 bpf_attach(&sc->intf, 0, 0); 282 #endif 283 softcv[unit] = sc; 284 atomic_inc_uint(&srt_count); 285 return 0; 286 } 287 288 static int 289 srt_clone_destroy(struct ifnet *ifp) 290 { 291 struct srt_softc *sc; 292 293 sc = ifp->if_softc; 294 if ((ifp->if_flags & IFF_UP) || (sc->kflags & SKF_CDEVOPEN)) 295 return EBUSY; 296 #ifdef BPFILTER_NOW_AVAILABLE 297 bpf_detach(ifp); 298 #endif 299 if_detach(ifp); 300 if (sc->unit < 0 || sc->unit > SRT_MAXUNIT) { 301 panic("srt_clone_destroy: impossible unit %d\n",sc->unit); 302 } 303 if (softcv[sc->unit] != sc) { 304 panic("srt_clone_destroy: bad backpointer ([%d]=%p not %p)\n", 305 sc->unit, (void *)softcv[sc->unit], (void *)sc); 306 } 307 softcv[sc->unit] = 0; 308 free(sc, M_DEVBUF); 309 atomic_inc_uint(&srt_count); 310 return 0; 311 } 312 313 struct if_clone srt_clone = 314 IF_CLONE_INITIALIZER("srt", &srt_clone_create, &srt_clone_destroy); 315 316 void 317 srtattach(int n) 318 { 319 320 /* 321 * Nothing to do here, initialization is handled by the 322 * module initialization code in srtinit() below). 323 */ 324 } 325 326 static void 327 srtinit(void) 328 { 329 int i; 330 331 for (i = SRT_MAXUNIT; i >= 0; i--) 332 softcv[i] = 0; 333 global_flags = 0; 334 if_clone_attach(&srt_clone); 335 } 336 337 static int 338 srtdetach(void) 339 { 340 int error = 0; 341 int i; 342 343 for (i = SRT_MAXUNIT; i >= 0; i--) 344 if(softcv[i]) { 345 error = EBUSY; 346 break; 347 } 348 349 if (error == 0) 350 if_clone_detach(&srt_clone); 351 352 return error; 353 } 354 355 /* Special-device interface. */ 356 357 static int 358 srt_open(dev_t dev, int flag, int mode, struct lwp *l) 359 { 360 int unit; 361 struct srt_softc *sc; 362 363 unit = minor(dev); 364 if (unit < 0 || unit > SRT_MAXUNIT) 365 return ENXIO; 366 sc = softcv[unit]; 367 if (! sc) 368 return ENXIO; 369 sc->kflags |= SKF_CDEVOPEN; 370 return 0; 371 } 372 373 static int 374 srt_close(dev_t dev, int flag, int mode, struct lwp *l) 375 { 376 int unit; 377 struct srt_softc *sc; 378 379 unit = minor(dev); 380 if (unit < 0 || unit > SRT_MAXUNIT) 381 return ENXIO; 382 sc = softcv[unit]; 383 if (! sc) 384 return ENXIO; 385 sc->kflags &= ~SKF_CDEVOPEN; 386 return 0; 387 } 388 389 static int 390 srt_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 391 { 392 unsigned int f, i, n, o; 393 struct srt_softc *sc; 394 struct srt_rt *dr; 395 struct srt_rt *scr; 396 struct ifnet *ifp; 397 char nbuf[IFNAMSIZ]; 398 399 sc = softcv[minor(dev)]; 400 if (! sc) 401 panic("srt_ioctl: softc disappeared"); 402 switch (cmd) { 403 case SRT_GETNRT: 404 if (! (flag & FREAD)) 405 return EBADF; 406 *(unsigned int *)data = sc->nrt; 407 return 0; 408 case SRT_GETRT: 409 if (! (flag & FREAD)) 410 return EBADF; 411 dr = (struct srt_rt *) data; 412 if (dr->inx >= sc->nrt) 413 return EDOM; 414 scr = sc->rts[dr->inx]; 415 dr->af = scr->af; 416 dr->srcmatch = scr->srcmatch; 417 dr->srcmask = scr->srcmask; 418 strlcpy(&dr->u.dstifn[0], &scr->u.dstifp->if_xname[0], 419 IFNAMSIZ); 420 memcpy(&dr->dst, &scr->dst, scr->dst.sa.sa_len); 421 return 0; 422 case SRT_SETRT: 423 if (! (flag & FWRITE)) 424 return EBADF; 425 dr = (struct srt_rt *) data; 426 if (dr->inx > sc->nrt) 427 return EDOM; 428 strlcpy(&nbuf[0], &dr->u.dstifn[0], IFNAMSIZ); 429 nbuf[IFNAMSIZ-1] = '\0'; 430 if (dr->dst.sa.sa_family != dr->af) 431 return EIO; 432 switch (dr->af) { 433 #ifdef INET 434 case AF_INET: 435 if (dr->dst.sa.sa_len != sizeof(dr->dst.sin)) 436 return EIO; 437 if (dr->srcmask > 32) 438 return EIO; 439 break; 440 #endif 441 #ifdef INET6 442 case AF_INET6: 443 if (dr->dst.sa.sa_len != sizeof(dr->dst.sin6)) 444 return EIO; 445 if (dr->srcmask > 128) 446 return EIO; 447 break; 448 #endif 449 default: 450 return EAFNOSUPPORT; 451 } 452 ifp = ifunit(&nbuf[0]); 453 if (ifp == 0) 454 return ENXIO; /* needs translation */ 455 if (dr->inx == sc->nrt) { 456 struct srt_rt **tmp; 457 tmp = malloc((sc->nrt+1)*sizeof(*tmp), M_DEVBUF, 458 M_WAITOK); 459 if (tmp == 0) 460 return ENOBUFS; 461 tmp[sc->nrt] = 0; 462 if (sc->nrt > 0) { 463 memcpy(tmp, sc->rts, sc->nrt*sizeof(*tmp)); 464 free(sc->rts, M_DEVBUF); 465 } 466 sc->rts = tmp; 467 sc->nrt ++; 468 } 469 scr = sc->rts[dr->inx]; 470 if (scr == 0) { 471 scr = malloc(sizeof(struct srt_rt), M_DEVBUF,M_WAITOK); 472 if (scr == 0) 473 return ENOBUFS; 474 scr->inx = dr->inx; 475 scr->af = AF_UNSPEC; 476 sc->rts[dr->inx] = scr; 477 } 478 scr->af = dr->af; 479 scr->srcmatch = dr->srcmatch; 480 scr->srcmask = dr->srcmask; 481 scr->u.dstifp = ifp; 482 memcpy(&scr->dst,&dr->dst,dr->dst.sa.sa_len); 483 if (dr->af == AF_INET6) 484 in6_setzoneid(&scr->dst.sin6.sin6_addr, ifp->if_index); 485 update_mtu(sc); 486 return 0; 487 case SRT_DELRT: 488 if (! (flag & FWRITE)) 489 return EBADF; 490 i = *(unsigned int *)data; 491 if (i >= sc->nrt) 492 return EDOM; 493 scr = sc->rts[i]; 494 sc->rts[i] = 0; 495 free(scr, M_DEVBUF); 496 sc->nrt--; 497 if (i < sc->nrt) { 498 memcpy(sc->rts+i, sc->rts+i+1, 499 (sc->nrt-i) * sizeof(*sc->rts)); 500 } 501 if (sc->nrt == 0) { 502 free(sc->rts, M_DEVBUF); 503 sc->rts = 0; 504 sc->intf.if_flags &= ~IFF_UP; 505 } 506 update_mtu(sc); 507 return 0; 508 case SRT_SFLAGS: 509 if (! (flag & FWRITE)) 510 return EBADF; 511 f = *(unsigned int *)data & SSF_UCHG; 512 global_flags = (global_flags & ~SSF_UCHG) | (f & SSF_GLOBAL); 513 sc->flags = (sc->flags & ~SSF_UCHG) | (f & ~SSF_GLOBAL); 514 return 0; 515 case SRT_GFLAGS: 516 if (! (flag & FREAD)) 517 return EBADF; 518 *(unsigned int *)data = sc->flags | global_flags; 519 return 0; 520 case SRT_SGFLAGS: 521 if ((flag & (FWRITE | FREAD)) != (FWRITE | FREAD)) 522 return EBADF; 523 o = sc->flags | global_flags; 524 n = *(unsigned int *)data & SSF_UCHG; 525 global_flags = (global_flags & ~SSF_UCHG) | (n & SSF_GLOBAL); 526 sc->flags = (sc->flags & ~SSF_UCHG) | (n & ~SSF_GLOBAL); 527 *(unsigned int *)data = o; 528 return 0; 529 case SRT_DEBUG: 530 return 0; 531 break; 532 } 533 return ENOTTY; 534 } 535 536 const struct cdevsw srt_cdevsw = { 537 .d_open = srt_open, 538 .d_close = srt_close, 539 .d_read = nullread, 540 .d_write = nullwrite, 541 .d_ioctl = srt_ioctl, 542 .d_stop = nullstop, 543 .d_tty = notty, 544 .d_poll = nullpoll, 545 .d_mmap = nommap, 546 .d_kqfilter = nullkqfilter, 547 .d_discard = nodiscard, 548 .d_flag = D_OTHER 549 }; 550 551 /* 552 * Module infrastructure 553 */ 554 #include "if_module.h" 555 556 IF_MODULE(MODULE_CLASS_DRIVER, srt, "") 557