xref: /netbsd-src/sys/net/if_srt.c (revision 7fa608457b817eca6e0977b37f758ae064f3c99c)
1 /* $NetBSD: if_srt.c,v 1.5 2007/03/04 06:03:17 christos Exp $ */
2 /* This file is in the public domain. */
3 
4 #include "opt_inet.h"
5 
6 #if !defined(INET) && !defined(INET6)
7 #error "srt without INET/INET6?"
8 #endif
9 
10 #ifndef SRT_MAXUNIT
11 #define SRT_MAXUNIT 255
12 #endif
13 
14 /* include-file bug workarounds */
15 #include <sys/types.h> /* sys/conf.h */
16 #include <sys/resource.h> /* sys/resourcevar.h (uvm/uvm_param.h, sys/mbuf.h) */
17 #include <netinet/in.h> /* netinet/ip.h */
18 #include <sys/param.h> /* sys/mbuf.h */
19 #include <netinet/in_systm.h> /* netinet/ip.h */
20 
21 #include <sys/conf.h>
22 #include <sys/mbuf.h>
23 #include <sys/errno.h>
24 #include <sys/fcntl.h>
25 #include <sys/param.h>
26 #include <sys/ioctl.h>
27 #include <netinet/ip.h>
28 #include <netinet/ip6.h>
29 #include <net/if_types.h>
30 #include <machine/stdarg.h>
31 
32 #include "if_srt.h"
33 #include "bpfilter.h"
34 
35 /* until we know what to pass to bpfattach.... */
36 #undef NBPFILTER
37 #define NBPFILTER 0
38 
39 typedef struct srt_rt RT;
40 typedef struct softc SOFTC;
41 
42 struct softc {
43   struct ifnet intf;	/* XXX interface botch */
44   int unit;
45   int nrt;
46   RT **rts;
47   unsigned int flags;	/* SSF_* values from if_srt.h */
48 #define SSF_UCHG (SSF_MTULOCK) /* userland-changeable bits */
49   unsigned int kflags;	/* bits private to this file */
50 #define SKF_CDEVOPEN 0x00000001
51   } ;
52 
53 static SOFTC *softcv[SRT_MAXUNIT+1];
54 static unsigned int global_flags;
55 
56 /* Internal routines. */
57 
58 static unsigned int ipv4_masks[33]
59  = { 0x00000000, /* /0 */
60      0x80000000, 0xc0000000, 0xe0000000, 0xf0000000, /* /1 - /4 */
61      0xf8000000, 0xfc000000, 0xfe000000, 0xff000000, /* /5 - /8 */
62      0xff800000, 0xffc00000, 0xffe00000, 0xfff00000, /* /9 - /12 */
63      0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000, /* /13 - /16 */
64      0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000, /* /17 - /20 */
65      0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00, /* /21 - /24 */
66      0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0, /* /25 - /28 */
67      0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff  /* /29 - /32 */ };
68 
69 static void update_mtu(SOFTC *sc)
70 {
71  int mtu;
72  int i;
73  RT *r;
74 
75  if (sc->flags & SSF_MTULOCK) return;
76  mtu = 65535;
77  for (i=sc->nrt-1;i>=0;i--)
78   { r = sc->rts[i];
79     if (r->u.dstifp->if_mtu < mtu) mtu = r->u.dstifp->if_mtu;
80   }
81  sc->intf.if_mtu = mtu;
82 }
83 
84 static RT *find_rt(SOFTC *sc, int af, ...)
85 {
86  int i;
87  RT *r;
88  struct in_addr ia;
89  struct in6_addr ia6;
90  va_list ap;
91 
92  ia.s_addr = 0; ia6.s6_addr[0] = 0; /* shut up incorrect -Wuninitialized */
93  va_start(ap,af);
94  switch (af)
95   { case AF_INET:
96        ia = va_arg(ap,struct in_addr);
97        break;
98     case AF_INET6:
99        ia6 = va_arg(ap,struct in6_addr);
100        break;
101     default:
102        panic("if_srt find_rt: impossible address family");
103        break;
104   }
105  va_end(ap);
106  for (i=0;i<sc->nrt;i++)
107   { r = sc->rts[i];
108     if (r->af != af) continue;
109     switch (af)
110      { case AF_INET:
111 	  if ((ia.s_addr & ipv4_masks[r->srcmask]) == r->srcmatch.v4.s_addr) return(r);
112 	  break;
113        case AF_INET6:
114 	  if ((r->srcmask >= 8) && bcmp(&ia6,&r->srcmatch.v6,r->srcmask/8)) continue;
115 	  if ( (r->srcmask % 8) &&
116 	       ( ( ia6.s6_addr[r->srcmask/8] ^
117 		   r->srcmatch.v6.s6_addr[r->srcmask/8] ) &
118 		 0xff & (0xff00 >> (r->srcmask%8)) ) ) continue;
119 	  return(r);
120 	  break;
121        default:
122 	  panic("if_srt find_rt: impossible address family 2");
123 	  break;
124      }
125   }
126  return(0);
127 }
128 
129 /* Network device interface. */
130 
131 static int srt_if_ioctl(struct ifnet *intf, u_long cmd, void *data)
132 {
133  struct ifaddr *ifa;
134  struct ifreq *ifr;
135  int s;
136  int err;
137 
138  err = 0;
139  s = splnet();
140  switch (cmd)
141   { case SIOCSIFADDR:
142     case SIOCSIFDSTADDR:
143        ifa = (void *) data;
144        switch (ifa->ifa_addr->sa_family)
145 	{
146 #ifdef INET
147 	  case AF_INET:
148 #endif
149 #ifdef INET6
150 	  case AF_INET6:
151 #endif
152 	     break;
153 	  default:
154 	     err = EAFNOSUPPORT;
155 	     break;
156 	}
157        /* XXX do we need to do more here for either of these? */
158        break;
159     case SIOCSIFMTU:
160        ifr = (void *) data;
161        ((SOFTC *)intf->if_softc)->intf.if_mtu = ifr->ifr_mtu;
162        break;
163     case SIOCGIFMTU:
164        ifr = (void *) data;
165        ifr->ifr_mtu = intf->if_mtu;
166        break;
167     default:
168        err = EINVAL;
169        break;
170   }
171  splx(s);
172  return(err);
173 }
174 
175 static int srt_if_output(
176 	struct ifnet *intf,
177 	struct mbuf *m,
178 	const struct sockaddr *to,
179 	struct rtentry *rtp )
180 {
181  SOFTC *sc;
182  RT *r;
183 
184  sc = intf->if_softc;
185  if (! (intf->if_flags & IFF_UP))
186   { m_freem(m);
187     return(ENETDOWN);
188   }
189  switch (to->sa_family)
190   {
191 #ifdef INET
192     case AF_INET:
193 #endif
194 	{ struct ip *ip;
195 	  ip = mtod(m,struct ip *);
196 	  r = find_rt(sc,AF_INET,ip->ip_src);
197 	}
198        break;
199 #ifdef INET6
200     case AF_INET6:
201 #endif
202 	{ struct ip6_hdr *ip;
203 	  ip = mtod(m,struct ip6_hdr *);
204 	  r = find_rt(sc,AF_INET6,ip->ip6_src);
205 	}
206        break;
207     default:
208        IF_DROP(&intf->if_snd);
209        m_freem(m);
210        return(EAFNOSUPPORT);
211        break;
212   }
213  /* XXX Do we need to bpf_tap?  Or do higher layers now handle that? */
214  /* if_gif.c seems to imply the latter. */
215  intf->if_opackets ++;
216  if (! r)
217   { intf->if_oerrors ++;
218     m_freem(m);
219     return(0);
220   }
221  if (! (m->m_flags & M_PKTHDR))
222   { printf("srt_if_output no PKTHDR\n");
223     m_freem(m);
224     return(0);
225   }
226  intf->if_obytes += m->m_pkthdr.len;
227  if (! (r->u.dstifp->if_flags & IFF_UP))
228   { m_freem(m);
229     return(0); /* XXX ENETDOWN? */
230   }
231  /* XXX is 0 the right last arg here? */
232  return((*r->u.dstifp->if_output)(r->u.dstifp,m,&r->dst.sa,0));
233 }
234 
235 static int srt_clone_create(struct if_clone *cl, int unit)
236 {
237  SOFTC *sc;
238 
239  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
240  if (softcv[unit]) return(EBUSY);
241  sc = malloc(sizeof(SOFTC),M_DEVBUF,M_WAIT);
242  bzero(&sc->intf,sizeof(sc->intf)); /* XXX */
243  sc->unit = unit;
244  sc->nrt = 0;
245  sc->rts = 0;
246  sc->flags = 0;
247  sc->kflags = 0;
248  snprintf(&sc->intf.if_xname[0],sizeof(sc->intf.if_xname),"%s%d",cl->ifc_name,unit);
249  sc->intf.if_softc = sc;
250  sc->intf.if_mtu = 65535;
251  sc->intf.if_flags = IFF_POINTOPOINT;
252  sc->intf.if_type = IFT_OTHER;
253  sc->intf.if_ioctl = &srt_if_ioctl;
254  sc->intf.if_output = &srt_if_output;
255  sc->intf.if_dlt = DLT_RAW;
256  if_attach(&sc->intf);
257  if_alloc_sadl(&sc->intf);
258 #if NBPFILTER > 0 /* see comment near top */
259  bpfattach(&sc->intf,0/*???*/,0/*???*/);
260 #endif
261  softcv[unit] = sc;
262  return(0);
263 }
264 
265 static int srt_clone_destroy(struct ifnet *intf)
266 {
267  SOFTC *sc;
268 
269  sc = intf->if_softc;
270  if ((intf->if_flags & IFF_UP) || (sc->kflags & SKF_CDEVOPEN)) return(EBUSY);
271 #if NBPFILTER > 0
272  bpfdetach(intf);
273 #endif
274  if_detach(intf);
275  if ((sc->unit < 0) || (sc->unit > SRT_MAXUNIT))
276   { panic("srt_clone_destroy: impossible unit %d\n",sc->unit);
277   }
278  if (softcv[sc->unit] != sc)
279   { panic("srt_clone_destroy: bad backpointer ([%d]=%p not %p)\n",
280 			sc->unit,(void *)softcv[sc->unit],(void *)sc);
281   }
282  softcv[sc->unit] = 0;
283  free(sc,M_DEVBUF);
284  return(0);
285 }
286 
287 struct if_clone srt_clone =
288     IF_CLONE_INITIALIZER("srt",&srt_clone_create,&srt_clone_destroy);
289 
290 extern void srtattach(void);
291 void srtattach(void)
292 {
293  int i;
294 
295  for (i=SRT_MAXUNIT;i>=0;i--) softcv[i] = 0;
296  global_flags = 0;
297  if_clone_attach(&srt_clone);
298 }
299 
300 /* Special-device interface. */
301 
302 static int srt_open(dev_t dev, int flag, int mode, struct lwp *l)
303 {
304  int unit;
305  SOFTC *sc;
306 
307  unit = minor(dev);
308  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
309  sc = softcv[unit];
310  if (! sc) return(ENXIO);
311  sc->kflags |= SKF_CDEVOPEN;
312  return(0);
313 }
314 
315 static int srt_close(dev_t dev, int flag, int mode, struct lwp *l)
316 {
317  int unit;
318  SOFTC *sc;
319 
320  unit = minor(dev);
321  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
322  sc = softcv[unit];
323  if (! sc) return(ENXIO);
324  sc->kflags &= ~SKF_CDEVOPEN;
325  return(0);
326 }
327 
328 static int srt_ioctl(
329 	dev_t dev,
330 	u_long cmd,
331 	void *data,
332 	int flag,
333 	struct lwp *l )
334 {
335  SOFTC *sc;
336  RT *dr;
337  RT *scr;
338  struct ifnet *intf;
339  char nbuf[IFNAMSIZ];
340 
341  sc = softcv[minor(dev)];
342  if (! sc) panic("srt_ioctl: softc disappeared");
343  switch (cmd)
344   { case SRT_GETNRT:
345        if (! (flag & FREAD)) return(EBADF);
346        *(unsigned int *)data = sc->nrt;
347        return(0);
348        break;
349     case SRT_GETRT:
350        if (! (flag & FREAD)) return(EBADF);
351        dr = (RT *) data;
352        if (dr->inx >= sc->nrt) return(EDOM);
353        scr = sc->rts[dr->inx];
354        dr->af = scr->af;
355        dr->srcmatch = scr->srcmatch;
356        dr->srcmask = scr->srcmask;
357        strncpy(&dr->u.dstifn[0],&scr->u.dstifp->if_xname[0],IFNAMSIZ);
358        memcpy(&dr->dst,&scr->dst,scr->dst.sa.sa_len);
359        return(0);
360        break;
361     case SRT_SETRT:
362        if (! (flag & FWRITE)) return(EBADF);
363        dr = (RT *) data;
364        if (dr->inx > sc->nrt) return(EDOM);
365        strncpy(&nbuf[0],&dr->u.dstifn[0],IFNAMSIZ);
366        nbuf[IFNAMSIZ-1] = '\0';
367        if (dr->dst.sa.sa_family != dr->af) return(EIO);
368        switch (dr->af)
369 	{
370 #ifdef INET
371 	  case AF_INET:
372 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin)) return(EIO);
373 	     if (dr->srcmask > 32) return(EIO);
374 	     break;
375 #endif
376 #ifdef INET6
377 	  case AF_INET6:
378 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin6)) return(EIO);
379 	     if (dr->srcmask > 128) return(EIO);
380 	     break;
381 #endif
382 	     break;
383 	  default:
384 	     return(EAFNOSUPPORT);
385 	     break;
386 	}
387        intf = ifunit(&nbuf[0]);
388        if (intf == 0) return(ENXIO); /* needs translation */
389        if (dr->inx == sc->nrt)
390 	{ RT **tmp;
391 	  tmp = malloc((sc->nrt+1)*sizeof(*tmp),M_DEVBUF,M_WAITOK);
392 	  if (tmp == 0) return(ENOBUFS);
393 	  tmp[sc->nrt] = 0;
394 	  if (sc->nrt > 0)
395 	   { memcpy(tmp,sc->rts,sc->nrt*sizeof(*tmp));
396 	     free(sc->rts,M_DEVBUF);
397 	   }
398 	  sc->rts = tmp;
399 	  sc->nrt ++;
400 	}
401        scr = sc->rts[dr->inx];
402        if (scr == 0)
403 	{ scr = malloc(sizeof(RT),M_DEVBUF,M_WAITOK);
404 	  if (scr == 0) return(ENOBUFS);
405 	  scr->inx = dr->inx;
406 	  scr->af = AF_UNSPEC;
407 	  sc->rts[dr->inx] = scr;
408 	}
409        scr->af = dr->af;
410        scr->srcmatch = dr->srcmatch;
411        scr->srcmask = dr->srcmask;
412        scr->u.dstifp = intf;
413        memcpy(&scr->dst,&dr->dst,dr->dst.sa.sa_len);
414        update_mtu(sc);
415        return(0);
416        break;
417     case SRT_DELRT:
418 	{ unsigned int i;
419 	  if (! (flag & FWRITE)) return(EBADF);
420 	  i = *(unsigned int *)data;
421 	  if (i >= sc->nrt) return(EDOM);
422 	  scr = sc->rts[i];
423 	  sc->rts[i] = 0;
424 	  free(scr,M_DEVBUF);
425 	  sc->nrt --;
426 	  if (i < sc->nrt) memcpy(sc->rts+i,sc->rts+i+1,(sc->nrt-i)*sizeof(*sc->rts));
427 	  if (sc->nrt == 0)
428 	   { free(sc->rts,M_DEVBUF);
429 	     sc->rts = 0;
430 	     sc->intf.if_flags &= ~IFF_UP;
431 	   }
432 	}
433        update_mtu(sc);
434        return(0);
435        break;
436     case SRT_SFLAGS:
437 	{ unsigned int f;
438 	  if (! (flag & FWRITE)) return(EBADF);
439 	  f = *(unsigned int *)data & SSF_UCHG;
440 	  global_flags = (global_flags & ~SSF_UCHG) | (f & SSF_GLOBAL);
441 	  sc->flags = (sc->flags & ~SSF_UCHG) | (f & ~SSF_GLOBAL);
442 	}
443        return(0);
444        break;
445     case SRT_GFLAGS:
446        if (! (flag & FREAD)) return(EBADF);
447        *(unsigned int *)data = sc->flags | global_flags;
448        return(0);
449        break;
450     case SRT_SGFLAGS:
451 	{ unsigned int o;
452 	  unsigned int n;
453 	  if ((flag & (FWRITE|FREAD)) != (FWRITE|FREAD)) return(EBADF);
454 	  o = sc->flags | global_flags;
455 	  n = *(unsigned int *)data & SSF_UCHG;
456 	  global_flags = (global_flags & ~SSF_UCHG) | (n & SSF_GLOBAL);
457 	  sc->flags = (sc->flags & ~SSF_UCHG) | (n & ~SSF_GLOBAL);
458 	  *(unsigned int *)data = o;
459 	}
460        return(0);
461        break;
462     case SRT_DEBUG:
463        return(0);
464        break;
465   }
466  return(ENOTTY);
467 }
468 
469 const struct cdevsw srt_cdevsw
470  = { &srt_open,
471      &srt_close,
472      nullread,
473      nullwrite,
474      &srt_ioctl,
475      nullstop,
476      notty,
477      nullpoll,
478      nommap,
479      nullkqfilter,
480      D_OTHER };
481