if_srt.c revision 1.17.12.1 1 /* $NetBSD: if_srt.c,v 1.17.12.1 2014/08/20 00:04:34 tls Exp $ */
2 /* This file is in the public domain. */
3
4 #include <sys/cdefs.h>
5 __KERNEL_RCSID(0, "$NetBSD: if_srt.c,v 1.17.12.1 2014/08/20 00:04:34 tls Exp $");
6
7 #include "opt_inet.h"
8
9 #if !defined(INET) && !defined(INET6)
10 #error "srt without INET/INET6?"
11 #endif
12
13 #ifndef SRT_MAXUNIT
14 #define SRT_MAXUNIT 255
15 #endif
16
17 /* include-file bug workarounds */
18 #include <sys/types.h> /* sys/conf.h */
19 #include <sys/resource.h> /* sys/resourcevar.h
20 * (uvm/uvm_param.h, sys/mbuf.h)
21 */
22 #include <netinet/in.h> /* netinet/ip.h */
23 #include <sys/param.h> /* sys/mbuf.h */
24 #include <netinet/in_systm.h> /* netinet/ip.h */
25
26 #include <sys/conf.h>
27 #include <sys/mbuf.h>
28 #include <sys/errno.h>
29 #include <sys/fcntl.h>
30 #include <sys/param.h>
31 #include <sys/ioctl.h>
32 #include <netinet/ip.h>
33 #include <netinet/ip6.h>
34 #include <net/if_types.h>
35
36 #include "if_srt.h"
37
38 /* until we know what to pass to bpfattach.... */
39 /* #define BPFILTER_NOW_AVAILABLE */
40
41 struct srt_softc {
42 struct ifnet intf; /* XXX interface botch */
43 int unit;
44 int nrt;
45 struct srt_rt **rts;
46 unsigned int flags; /* SSF_* values from if_srt.h */
47 #define SSF_UCHG (SSF_MTULOCK) /* userland-changeable bits */
48 unsigned int kflags; /* bits private to this file */
49 #define SKF_CDEVOPEN 0x00000001
50 };
51
52 void srtattach(void);
53
54 static struct srt_softc *softcv[SRT_MAXUNIT+1];
55 static unsigned int global_flags;
56
57 /* Internal routines. */
58
59 static unsigned int ipv4_masks[33] = {
60 0x00000000, /* /0 */
61 0x80000000, 0xc0000000, 0xe0000000, 0xf0000000, /* /1 - /4 */
62 0xf8000000, 0xfc000000, 0xfe000000, 0xff000000, /* /5 - /8 */
63 0xff800000, 0xffc00000, 0xffe00000, 0xfff00000, /* /9 - /12 */
64 0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000, /* /13 - /16 */
65 0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000, /* /17 - /20 */
66 0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00, /* /21 - /24 */
67 0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0, /* /25 - /28 */
68 0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff /* /29 - /32 */
69 };
70
71 static void
72 update_mtu(struct srt_softc *sc)
73 {
74 int mtu;
75 int i;
76 struct srt_rt *r;
77
78 if (sc->flags & SSF_MTULOCK)
79 return;
80 mtu = 65535;
81 for (i=sc->nrt-1;i>=0;i--) {
82 r = sc->rts[i];
83 if (r->u.dstifp->if_mtu < mtu)
84 mtu = r->u.dstifp->if_mtu;
85 }
86 sc->intf.if_mtu = mtu;
87 }
88
89 static struct srt_rt *
90 find_rt(struct srt_softc *sc, int af, ...)
91 {
92 int i;
93 struct srt_rt *r;
94 struct in_addr ia;
95 struct in6_addr ia6;
96 va_list ap;
97
98 ia.s_addr = 0; ia6.s6_addr[0] = 0; /* shut up incorrect -Wuninitialized */
99 va_start(ap,af);
100 switch (af) {
101 case AF_INET:
102 ia = va_arg(ap,struct in_addr);
103 break;
104 case AF_INET6:
105 ia6 = va_arg(ap,struct in6_addr);
106 break;
107 default:
108 panic("if_srt find_rt: impossible address family");
109 break;
110 }
111 va_end(ap);
112 for (i=0; i < sc->nrt; i++) {
113 r = sc->rts[i];
114 if (r->af != af)
115 continue;
116 switch (af) {
117 case AF_INET:
118 if ((ia.s_addr & htonl(ipv4_masks[r->srcmask])) ==
119 r->srcmatch.v4.s_addr)
120 return r;
121 break;
122 case AF_INET6:
123 if ((r->srcmask >= 8) &&
124 memcmp(&ia6,&r->srcmatch.v6,r->srcmask / 8) != 0)
125 continue;
126 if ((r->srcmask % 8) &&
127 ((ia6.s6_addr[r->srcmask / 8] ^
128 r->srcmatch.v6.s6_addr[r->srcmask / 8]) &
129 0xff & (0xff00 >> (r->srcmask % 8))))
130 continue;
131 return r;
132 default:
133 panic("if_srt find_rt: impossible address family 2");
134 break;
135 }
136 }
137 return 0;
138 }
139
140 /* Network device interface. */
141
142 static int
143 srt_if_ioctl(struct ifnet *ifp, u_long cmd, void *data)
144 {
145 struct ifaddr *ifa;
146 int s;
147 int err;
148
149 err = 0;
150 s = splnet();
151 switch (cmd) {
152 case SIOCINITIFADDR:
153 ifa = (void *) data;
154 switch (ifa->ifa_addr->sa_family) {
155 #ifdef INET
156 case AF_INET:
157 break;
158 #endif
159 #ifdef INET6
160 case AF_INET6:
161 break;
162 #endif
163 default:
164 err = EAFNOSUPPORT;
165 break;
166 }
167 break;
168 default:
169 if ((err = ifioctl_common(ifp, cmd, data)) == ENETRESET)
170 err = 0;
171 break;
172 }
173 splx(s);
174 return err;
175 }
176
177 static int
178 srt_if_output(
179 struct ifnet *ifp,
180 struct mbuf *m,
181 const struct sockaddr *to,
182 struct rtentry *rtp)
183 {
184 struct srt_softc *sc;
185 struct srt_rt *r;
186
187 sc = ifp->if_softc;
188 if (! (ifp->if_flags & IFF_UP)) {
189 m_freem(m);
190 return ENETDOWN;
191 }
192 switch (to->sa_family) {
193 #ifdef INET
194 case AF_INET: {
195 struct ip *ip;
196 ip = mtod(m,struct ip *);
197 r = find_rt(sc,AF_INET,ip->ip_src);
198 break;
199 }
200 #endif
201 #ifdef INET6
202 case AF_INET6: {
203 struct ip6_hdr *ip;
204 ip = mtod(m,struct ip6_hdr *);
205 r = find_rt(sc,AF_INET6,ip->ip6_src);
206 break;
207 }
208 #endif
209 default:
210 IF_DROP(&ifp->if_snd);
211 m_freem(m);
212 return EAFNOSUPPORT;
213 }
214 /* XXX Do we need to bpf_tap? Or do higher layers now handle that? */
215 /* if_gif.c seems to imply the latter. */
216 ifp->if_opackets ++;
217 if (! r) {
218 ifp->if_oerrors ++;
219 m_freem(m);
220 return 0;
221 }
222 if (! (m->m_flags & M_PKTHDR)) {
223 printf("srt_if_output no PKTHDR\n");
224 m_freem(m);
225 return 0;
226 }
227 ifp->if_obytes += m->m_pkthdr.len;
228 if (! (r->u.dstifp->if_flags & IFF_UP)) {
229 m_freem(m);
230 return 0; /* XXX ENETDOWN? */
231 }
232 /* XXX is 0 the right last arg here? */
233 return (*r->u.dstifp->if_output)(r->u.dstifp,m,&r->dst.sa,0);
234 }
235
236 static int
237 srt_clone_create(struct if_clone *cl, int unit)
238 {
239 struct srt_softc *sc;
240
241 if (unit < 0 || unit > SRT_MAXUNIT)
242 return ENXIO;
243 if (softcv[unit])
244 return EBUSY;
245 sc = malloc(sizeof(struct srt_softc), M_DEVBUF, M_WAITOK|M_ZERO);
246 sc->unit = unit;
247 sc->nrt = 0;
248 sc->rts = 0;
249 sc->flags = 0;
250 sc->kflags = 0;
251 if_initname(&sc->intf,cl->ifc_name,unit);
252 sc->intf.if_softc = sc;
253 sc->intf.if_mtu = 65535;
254 sc->intf.if_flags = IFF_POINTOPOINT;
255 sc->intf.if_type = IFT_OTHER;
256 sc->intf.if_ioctl = &srt_if_ioctl;
257 sc->intf.if_output = &srt_if_output;
258 sc->intf.if_dlt = DLT_RAW;
259 if_attach(&sc->intf);
260 if_alloc_sadl(&sc->intf);
261 #ifdef BPFILTER_NOW_AVAILABLE
262 bpf_attach(&sc->intf, 0, 0);
263 #endif
264 softcv[unit] = sc;
265 return 0;
266 }
267
268 static int
269 srt_clone_destroy(struct ifnet *ifp)
270 {
271 struct srt_softc *sc;
272
273 sc = ifp->if_softc;
274 if ((ifp->if_flags & IFF_UP) || (sc->kflags & SKF_CDEVOPEN))
275 return EBUSY;
276 #ifdef BPFILTER_NOW_AVAILABLE
277 bpf_detach(ifp);
278 #endif
279 if_detach(ifp);
280 if (sc->unit < 0 || sc->unit > SRT_MAXUNIT) {
281 panic("srt_clone_destroy: impossible unit %d\n",sc->unit);
282 }
283 if (softcv[sc->unit] != sc) {
284 panic("srt_clone_destroy: bad backpointer ([%d]=%p not %p)\n",
285 sc->unit,(void *)softcv[sc->unit],(void *)sc);
286 }
287 softcv[sc->unit] = 0;
288 free(sc,M_DEVBUF);
289 return 0;
290 }
291
292 struct if_clone srt_clone =
293 IF_CLONE_INITIALIZER("srt",&srt_clone_create,&srt_clone_destroy);
294
295 void
296 srtattach(void)
297 {
298 int i;
299
300 for (i=SRT_MAXUNIT;i>=0;i--)
301 softcv[i] = 0;
302 global_flags = 0;
303 if_clone_attach(&srt_clone);
304 }
305
306 /* Special-device interface. */
307
308 static int
309 srt_open(dev_t dev, int flag, int mode, struct lwp *l)
310 {
311 int unit;
312 struct srt_softc *sc;
313
314 unit = minor(dev);
315 if (unit < 0 || unit > SRT_MAXUNIT)
316 return ENXIO;
317 sc = softcv[unit];
318 if (! sc)
319 return ENXIO;
320 sc->kflags |= SKF_CDEVOPEN;
321 return 0;
322 }
323
324 static int
325 srt_close(dev_t dev, int flag, int mode, struct lwp *l)
326 {
327 int unit;
328 struct srt_softc *sc;
329
330 unit = minor(dev);
331 if (unit < 0 || unit > SRT_MAXUNIT)
332 return ENXIO;
333 sc = softcv[unit];
334 if (! sc)
335 return ENXIO;
336 sc->kflags &= ~SKF_CDEVOPEN;
337 return 0;
338 }
339
340 static int
341 srt_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
342 {
343 unsigned int f, i, n, o;
344 struct srt_softc *sc;
345 struct srt_rt *dr;
346 struct srt_rt *scr;
347 struct ifnet *ifp;
348 char nbuf[IFNAMSIZ];
349
350 sc = softcv[minor(dev)];
351 if (! sc)
352 panic("srt_ioctl: softc disappeared");
353 switch (cmd) {
354 case SRT_GETNRT:
355 if (! (flag & FREAD))
356 return EBADF;
357 *(unsigned int *)data = sc->nrt;
358 return 0;
359 case SRT_GETRT:
360 if (! (flag & FREAD))
361 return EBADF;
362 dr = (struct srt_rt *) data;
363 if (dr->inx >= sc->nrt)
364 return EDOM;
365 scr = sc->rts[dr->inx];
366 dr->af = scr->af;
367 dr->srcmatch = scr->srcmatch;
368 dr->srcmask = scr->srcmask;
369 strncpy(&dr->u.dstifn[0],&scr->u.dstifp->if_xname[0],IFNAMSIZ);
370 memcpy(&dr->dst,&scr->dst,scr->dst.sa.sa_len);
371 return 0;
372 case SRT_SETRT:
373 if (! (flag & FWRITE))
374 return EBADF;
375 dr = (struct srt_rt *) data;
376 if (dr->inx > sc->nrt)
377 return EDOM;
378 strncpy(&nbuf[0],&dr->u.dstifn[0],IFNAMSIZ);
379 nbuf[IFNAMSIZ-1] = '\0';
380 if (dr->dst.sa.sa_family != dr->af)
381 return EIO;
382 switch (dr->af) {
383 #ifdef INET
384 case AF_INET:
385 if (dr->dst.sa.sa_len != sizeof(dr->dst.sin))
386 return EIO;
387 if (dr->srcmask > 32)
388 return EIO;
389 break;
390 #endif
391 #ifdef INET6
392 case AF_INET6:
393 if (dr->dst.sa.sa_len != sizeof(dr->dst.sin6))
394 return EIO;
395 if (dr->srcmask > 128)
396 return EIO;
397 break;
398 #endif
399 default:
400 return EAFNOSUPPORT;
401 }
402 ifp = ifunit(&nbuf[0]);
403 if (ifp == 0)
404 return ENXIO; /* needs translation */
405 if (dr->inx == sc->nrt) {
406 struct srt_rt **tmp;
407 tmp = malloc((sc->nrt+1)*sizeof(*tmp), M_DEVBUF,
408 M_WAITOK);
409 if (tmp == 0)
410 return ENOBUFS;
411 tmp[sc->nrt] = 0;
412 if (sc->nrt > 0) {
413 memcpy(tmp, sc->rts, sc->nrt*sizeof(*tmp));
414 free(sc->rts, M_DEVBUF);
415 }
416 sc->rts = tmp;
417 sc->nrt ++;
418 }
419 scr = sc->rts[dr->inx];
420 if (scr == 0) {
421 scr = malloc(sizeof(struct srt_rt),M_DEVBUF,M_WAITOK);
422 if (scr == 0)
423 return ENOBUFS;
424 scr->inx = dr->inx;
425 scr->af = AF_UNSPEC;
426 sc->rts[dr->inx] = scr;
427 }
428 scr->af = dr->af;
429 scr->srcmatch = dr->srcmatch;
430 scr->srcmask = dr->srcmask;
431 scr->u.dstifp = ifp;
432 memcpy(&scr->dst,&dr->dst,dr->dst.sa.sa_len);
433 update_mtu(sc);
434 return 0;
435 case SRT_DELRT:
436 if (! (flag & FWRITE))
437 return EBADF;
438 i = *(unsigned int *)data;
439 if (i >= sc->nrt)
440 return EDOM;
441 scr = sc->rts[i];
442 sc->rts[i] = 0;
443 free(scr, M_DEVBUF);
444 sc->nrt--;
445 if (i < sc->nrt) {
446 memcpy(sc->rts+i, sc->rts+i+1,
447 (sc->nrt-i)*sizeof(*sc->rts));
448 }
449 if (sc->nrt == 0) {
450 free(sc->rts, M_DEVBUF);
451 sc->rts = 0;
452 sc->intf.if_flags &= ~IFF_UP;
453 }
454 update_mtu(sc);
455 return 0;
456 case SRT_SFLAGS:
457 if (! (flag & FWRITE))
458 return EBADF;
459 f = *(unsigned int *)data & SSF_UCHG;
460 global_flags = (global_flags & ~SSF_UCHG) | (f & SSF_GLOBAL);
461 sc->flags = (sc->flags & ~SSF_UCHG) | (f & ~SSF_GLOBAL);
462 return 0;
463 case SRT_GFLAGS:
464 if (! (flag & FREAD))
465 return EBADF;
466 *(unsigned int *)data = sc->flags | global_flags;
467 return 0;
468 case SRT_SGFLAGS:
469 if ((flag & (FWRITE|FREAD)) != (FWRITE|FREAD))
470 return EBADF;
471 o = sc->flags | global_flags;
472 n = *(unsigned int *)data & SSF_UCHG;
473 global_flags = (global_flags & ~SSF_UCHG) | (n & SSF_GLOBAL);
474 sc->flags = (sc->flags & ~SSF_UCHG) | (n & ~SSF_GLOBAL);
475 *(unsigned int *)data = o;
476 return 0;
477 case SRT_DEBUG:
478 return 0;
479 break;
480 }
481 return ENOTTY;
482 }
483
484 const struct cdevsw srt_cdevsw = {
485 .d_open = srt_open,
486 .d_close = srt_close,
487 .d_read = nullread,
488 .d_write = nullwrite,
489 .d_ioctl = srt_ioctl,
490 .d_stop = nullstop,
491 .d_tty = notty,
492 .d_poll = nullpoll,
493 .d_mmap = nommap,
494 .d_kqfilter = nullkqfilter,
495 .d_discard = nodiscard,
496 .d_flag = D_OTHER
497 };
498