xref: /netbsd-src/sys/net/if_srt.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /* $NetBSD: if_srt.c,v 1.9 2008/11/07 00:20:13 dyoung Exp $ */
2 /* This file is in the public domain. */
3 
4 #include <sys/cdefs.h>
5 __KERNEL_RCSID(0, "$NetBSD: if_srt.c,v 1.9 2008/11/07 00:20:13 dyoung 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 (uvm/uvm_param.h, sys/mbuf.h) */
20 #include <netinet/in.h> /* netinet/ip.h */
21 #include <sys/param.h> /* sys/mbuf.h */
22 #include <netinet/in_systm.h> /* netinet/ip.h */
23 
24 #include <sys/conf.h>
25 #include <sys/mbuf.h>
26 #include <sys/errno.h>
27 #include <sys/fcntl.h>
28 #include <sys/param.h>
29 #include <sys/ioctl.h>
30 #include <netinet/ip.h>
31 #include <netinet/ip6.h>
32 #include <net/if_types.h>
33 #include <machine/stdarg.h>
34 
35 #include "if_srt.h"
36 #include "bpfilter.h"
37 
38 /* until we know what to pass to bpfattach.... */
39 #undef NBPFILTER
40 #define NBPFILTER 0
41 
42 typedef struct srt_rt RT;
43 typedef struct softc SOFTC;
44 
45 struct softc {
46   struct ifnet intf;	/* XXX interface botch */
47   int unit;
48   int nrt;
49   RT **rts;
50   unsigned int flags;	/* SSF_* values from if_srt.h */
51 #define SSF_UCHG (SSF_MTULOCK) /* userland-changeable bits */
52   unsigned int kflags;	/* bits private to this file */
53 #define SKF_CDEVOPEN 0x00000001
54   } ;
55 
56 static SOFTC *softcv[SRT_MAXUNIT+1];
57 static unsigned int global_flags;
58 
59 /* Internal routines. */
60 
61 static unsigned int ipv4_masks[33]
62  = { 0x00000000, /* /0 */
63      0x80000000, 0xc0000000, 0xe0000000, 0xf0000000, /* /1 - /4 */
64      0xf8000000, 0xfc000000, 0xfe000000, 0xff000000, /* /5 - /8 */
65      0xff800000, 0xffc00000, 0xffe00000, 0xfff00000, /* /9 - /12 */
66      0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000, /* /13 - /16 */
67      0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000, /* /17 - /20 */
68      0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00, /* /21 - /24 */
69      0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0, /* /25 - /28 */
70      0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff  /* /29 - /32 */ };
71 
72 static void update_mtu(SOFTC *sc)
73 {
74  int mtu;
75  int i;
76  RT *r;
77 
78  if (sc->flags & SSF_MTULOCK) return;
79  mtu = 65535;
80  for (i=sc->nrt-1;i>=0;i--)
81   { r = sc->rts[i];
82     if (r->u.dstifp->if_mtu < mtu) mtu = r->u.dstifp->if_mtu;
83   }
84  sc->intf.if_mtu = mtu;
85 }
86 
87 static RT *find_rt(SOFTC *sc, int af, ...)
88 {
89  int i;
90  RT *r;
91  struct in_addr ia;
92  struct in6_addr ia6;
93  va_list ap;
94 
95  ia.s_addr = 0; ia6.s6_addr[0] = 0; /* shut up incorrect -Wuninitialized */
96  va_start(ap,af);
97  switch (af)
98   { case AF_INET:
99        ia = va_arg(ap,struct in_addr);
100        break;
101     case AF_INET6:
102        ia6 = va_arg(ap,struct in6_addr);
103        break;
104     default:
105        panic("if_srt find_rt: impossible address family");
106        break;
107   }
108  va_end(ap);
109  for (i=0;i<sc->nrt;i++)
110   { r = sc->rts[i];
111     if (r->af != af) continue;
112     switch (af)
113      { case AF_INET:
114 	  if ((ia.s_addr & ipv4_masks[r->srcmask]) == r->srcmatch.v4.s_addr) return(r);
115 	  break;
116        case AF_INET6:
117 	  if ((r->srcmask >= 8) && bcmp(&ia6,&r->srcmatch.v6,r->srcmask/8)) continue;
118 	  if ( (r->srcmask % 8) &&
119 	       ( ( ia6.s6_addr[r->srcmask/8] ^
120 		   r->srcmatch.v6.s6_addr[r->srcmask/8] ) &
121 		 0xff & (0xff00 >> (r->srcmask%8)) ) ) continue;
122 	  return(r);
123 	  break;
124        default:
125 	  panic("if_srt find_rt: impossible address family 2");
126 	  break;
127      }
128   }
129  return(0);
130 }
131 
132 /* Network device interface. */
133 
134 static int srt_if_ioctl(struct ifnet *intf, u_long cmd, void *data)
135 {
136  struct ifaddr *ifa;
137  int s;
138  int err;
139 
140  err = 0;
141  s = splnet();
142  switch (cmd)
143   { case SIOCINITIFADDR:
144     case SIOCSIFDSTADDR:
145        ifa = (void *) data;
146        switch (ifa->ifa_addr->sa_family)
147 	{
148 #ifdef INET
149 	  case AF_INET:
150 #endif
151 #ifdef INET6
152 	  case AF_INET6:
153 #endif
154 	     break;
155 	  default:
156 	     err = EAFNOSUPPORT;
157 	     break;
158 	}
159        /* XXX do we need to do more here for either of these? */
160        break;
161     default:
162        if ((err = ifioctl_common(intf, cmd, data)) == ENETRESET)
163              err = 0;
164        break;
165   }
166  splx(s);
167  return(err);
168 }
169 
170 static int srt_if_output(
171 	struct ifnet *intf,
172 	struct mbuf *m,
173 	const struct sockaddr *to,
174 	struct rtentry *rtp )
175 {
176  SOFTC *sc;
177  RT *r;
178 
179  sc = intf->if_softc;
180  if (! (intf->if_flags & IFF_UP))
181   { m_freem(m);
182     return(ENETDOWN);
183   }
184  switch (to->sa_family)
185   {
186 #ifdef INET
187     case AF_INET:
188 #endif
189 	{ struct ip *ip;
190 	  ip = mtod(m,struct ip *);
191 	  r = find_rt(sc,AF_INET,ip->ip_src);
192 	}
193        break;
194 #ifdef INET6
195     case AF_INET6:
196 #endif
197 	{ struct ip6_hdr *ip;
198 	  ip = mtod(m,struct ip6_hdr *);
199 	  r = find_rt(sc,AF_INET6,ip->ip6_src);
200 	}
201        break;
202     default:
203        IF_DROP(&intf->if_snd);
204        m_freem(m);
205        return(EAFNOSUPPORT);
206        break;
207   }
208  /* XXX Do we need to bpf_tap?  Or do higher layers now handle that? */
209  /* if_gif.c seems to imply the latter. */
210  intf->if_opackets ++;
211  if (! r)
212   { intf->if_oerrors ++;
213     m_freem(m);
214     return(0);
215   }
216  if (! (m->m_flags & M_PKTHDR))
217   { printf("srt_if_output no PKTHDR\n");
218     m_freem(m);
219     return(0);
220   }
221  intf->if_obytes += m->m_pkthdr.len;
222  if (! (r->u.dstifp->if_flags & IFF_UP))
223   { m_freem(m);
224     return(0); /* XXX ENETDOWN? */
225   }
226  /* XXX is 0 the right last arg here? */
227  return((*r->u.dstifp->if_output)(r->u.dstifp,m,&r->dst.sa,0));
228 }
229 
230 static int srt_clone_create(struct if_clone *cl, int unit)
231 {
232  SOFTC *sc;
233 
234  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
235  if (softcv[unit]) return(EBUSY);
236  sc = malloc(sizeof(SOFTC),M_DEVBUF,M_WAIT);
237  bzero(&sc->intf,sizeof(sc->intf)); /* XXX */
238  sc->unit = unit;
239  sc->nrt = 0;
240  sc->rts = 0;
241  sc->flags = 0;
242  sc->kflags = 0;
243  if_initname(&sc->intf,cl->ifc_name,unit);
244  sc->intf.if_softc = sc;
245  sc->intf.if_mtu = 65535;
246  sc->intf.if_flags = IFF_POINTOPOINT;
247  sc->intf.if_type = IFT_OTHER;
248  sc->intf.if_ioctl = &srt_if_ioctl;
249  sc->intf.if_output = &srt_if_output;
250  sc->intf.if_dlt = DLT_RAW;
251  if_attach(&sc->intf);
252  if_alloc_sadl(&sc->intf);
253 #if NBPFILTER > 0 /* see comment near top */
254  bpfattach(&sc->intf,0/*???*/,0/*???*/);
255 #endif
256  softcv[unit] = sc;
257  return(0);
258 }
259 
260 static int srt_clone_destroy(struct ifnet *intf)
261 {
262  SOFTC *sc;
263 
264  sc = intf->if_softc;
265  if ((intf->if_flags & IFF_UP) || (sc->kflags & SKF_CDEVOPEN)) return(EBUSY);
266 #if NBPFILTER > 0
267  bpfdetach(intf);
268 #endif
269  if_detach(intf);
270  if ((sc->unit < 0) || (sc->unit > SRT_MAXUNIT))
271   { panic("srt_clone_destroy: impossible unit %d\n",sc->unit);
272   }
273  if (softcv[sc->unit] != sc)
274   { panic("srt_clone_destroy: bad backpointer ([%d]=%p not %p)\n",
275 			sc->unit,(void *)softcv[sc->unit],(void *)sc);
276   }
277  softcv[sc->unit] = 0;
278  free(sc,M_DEVBUF);
279  return(0);
280 }
281 
282 struct if_clone srt_clone =
283     IF_CLONE_INITIALIZER("srt",&srt_clone_create,&srt_clone_destroy);
284 
285 extern void srtattach(void);
286 void srtattach(void)
287 {
288  int i;
289 
290  for (i=SRT_MAXUNIT;i>=0;i--) softcv[i] = 0;
291  global_flags = 0;
292  if_clone_attach(&srt_clone);
293 }
294 
295 /* Special-device interface. */
296 
297 static int srt_open(dev_t dev, int flag, int mode, struct lwp *l)
298 {
299  int unit;
300  SOFTC *sc;
301 
302  unit = minor(dev);
303  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
304  sc = softcv[unit];
305  if (! sc) return(ENXIO);
306  sc->kflags |= SKF_CDEVOPEN;
307  return(0);
308 }
309 
310 static int srt_close(dev_t dev, int flag, int mode, struct lwp *l)
311 {
312  int unit;
313  SOFTC *sc;
314 
315  unit = minor(dev);
316  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
317  sc = softcv[unit];
318  if (! sc) return(ENXIO);
319  sc->kflags &= ~SKF_CDEVOPEN;
320  return(0);
321 }
322 
323 static int srt_ioctl(
324 	dev_t dev,
325 	u_long cmd,
326 	void *data,
327 	int flag,
328 	struct lwp *l )
329 {
330  SOFTC *sc;
331  RT *dr;
332  RT *scr;
333  struct ifnet *intf;
334  char nbuf[IFNAMSIZ];
335 
336  sc = softcv[minor(dev)];
337  if (! sc) panic("srt_ioctl: softc disappeared");
338  switch (cmd)
339   { case SRT_GETNRT:
340        if (! (flag & FREAD)) return(EBADF);
341        *(unsigned int *)data = sc->nrt;
342        return(0);
343        break;
344     case SRT_GETRT:
345        if (! (flag & FREAD)) return(EBADF);
346        dr = (RT *) data;
347        if (dr->inx >= sc->nrt) return(EDOM);
348        scr = sc->rts[dr->inx];
349        dr->af = scr->af;
350        dr->srcmatch = scr->srcmatch;
351        dr->srcmask = scr->srcmask;
352        strncpy(&dr->u.dstifn[0],&scr->u.dstifp->if_xname[0],IFNAMSIZ);
353        memcpy(&dr->dst,&scr->dst,scr->dst.sa.sa_len);
354        return(0);
355        break;
356     case SRT_SETRT:
357        if (! (flag & FWRITE)) return(EBADF);
358        dr = (RT *) data;
359        if (dr->inx > sc->nrt) return(EDOM);
360        strncpy(&nbuf[0],&dr->u.dstifn[0],IFNAMSIZ);
361        nbuf[IFNAMSIZ-1] = '\0';
362        if (dr->dst.sa.sa_family != dr->af) return(EIO);
363        switch (dr->af)
364 	{
365 #ifdef INET
366 	  case AF_INET:
367 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin)) return(EIO);
368 	     if (dr->srcmask > 32) return(EIO);
369 	     break;
370 #endif
371 #ifdef INET6
372 	  case AF_INET6:
373 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin6)) return(EIO);
374 	     if (dr->srcmask > 128) return(EIO);
375 	     break;
376 #endif
377 	     break;
378 	  default:
379 	     return(EAFNOSUPPORT);
380 	     break;
381 	}
382        intf = ifunit(&nbuf[0]);
383        if (intf == 0) return(ENXIO); /* needs translation */
384        if (dr->inx == sc->nrt)
385 	{ RT **tmp;
386 	  tmp = malloc((sc->nrt+1)*sizeof(*tmp),M_DEVBUF,M_WAITOK);
387 	  if (tmp == 0) return(ENOBUFS);
388 	  tmp[sc->nrt] = 0;
389 	  if (sc->nrt > 0)
390 	   { memcpy(tmp,sc->rts,sc->nrt*sizeof(*tmp));
391 	     free(sc->rts,M_DEVBUF);
392 	   }
393 	  sc->rts = tmp;
394 	  sc->nrt ++;
395 	}
396        scr = sc->rts[dr->inx];
397        if (scr == 0)
398 	{ scr = malloc(sizeof(RT),M_DEVBUF,M_WAITOK);
399 	  if (scr == 0) return(ENOBUFS);
400 	  scr->inx = dr->inx;
401 	  scr->af = AF_UNSPEC;
402 	  sc->rts[dr->inx] = scr;
403 	}
404        scr->af = dr->af;
405        scr->srcmatch = dr->srcmatch;
406        scr->srcmask = dr->srcmask;
407        scr->u.dstifp = intf;
408        memcpy(&scr->dst,&dr->dst,dr->dst.sa.sa_len);
409        update_mtu(sc);
410        return(0);
411        break;
412     case SRT_DELRT:
413 	{ unsigned int i;
414 	  if (! (flag & FWRITE)) return(EBADF);
415 	  i = *(unsigned int *)data;
416 	  if (i >= sc->nrt) return(EDOM);
417 	  scr = sc->rts[i];
418 	  sc->rts[i] = 0;
419 	  free(scr,M_DEVBUF);
420 	  sc->nrt --;
421 	  if (i < sc->nrt) memcpy(sc->rts+i,sc->rts+i+1,(sc->nrt-i)*sizeof(*sc->rts));
422 	  if (sc->nrt == 0)
423 	   { free(sc->rts,M_DEVBUF);
424 	     sc->rts = 0;
425 	     sc->intf.if_flags &= ~IFF_UP;
426 	   }
427 	}
428        update_mtu(sc);
429        return(0);
430        break;
431     case SRT_SFLAGS:
432 	{ unsigned int f;
433 	  if (! (flag & FWRITE)) return(EBADF);
434 	  f = *(unsigned int *)data & SSF_UCHG;
435 	  global_flags = (global_flags & ~SSF_UCHG) | (f & SSF_GLOBAL);
436 	  sc->flags = (sc->flags & ~SSF_UCHG) | (f & ~SSF_GLOBAL);
437 	}
438        return(0);
439        break;
440     case SRT_GFLAGS:
441        if (! (flag & FREAD)) return(EBADF);
442        *(unsigned int *)data = sc->flags | global_flags;
443        return(0);
444        break;
445     case SRT_SGFLAGS:
446 	{ unsigned int o;
447 	  unsigned int n;
448 	  if ((flag & (FWRITE|FREAD)) != (FWRITE|FREAD)) return(EBADF);
449 	  o = sc->flags | global_flags;
450 	  n = *(unsigned int *)data & SSF_UCHG;
451 	  global_flags = (global_flags & ~SSF_UCHG) | (n & SSF_GLOBAL);
452 	  sc->flags = (sc->flags & ~SSF_UCHG) | (n & ~SSF_GLOBAL);
453 	  *(unsigned int *)data = o;
454 	}
455        return(0);
456        break;
457     case SRT_DEBUG:
458        return(0);
459        break;
460   }
461  return(ENOTTY);
462 }
463 
464 const struct cdevsw srt_cdevsw
465  = { &srt_open,
466      &srt_close,
467      nullread,
468      nullwrite,
469      &srt_ioctl,
470      nullstop,
471      notty,
472      nullpoll,
473      nommap,
474      nullkqfilter,
475      D_OTHER };
476