xref: /netbsd-src/sys/net/if_srt.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /* $NetBSD: if_srt.c,v 1.6 2007/12/11 12:37:46 lukem Exp $ */
2 /* This file is in the public domain. */
3 
4 #include <sys/cdefs.h>
5 __KERNEL_RCSID(0, "$NetBSD: if_srt.c,v 1.6 2007/12/11 12:37:46 lukem 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  struct ifreq *ifr;
138  int s;
139  int err;
140 
141  err = 0;
142  s = splnet();
143  switch (cmd)
144   { case SIOCSIFADDR:
145     case SIOCSIFDSTADDR:
146        ifa = (void *) data;
147        switch (ifa->ifa_addr->sa_family)
148 	{
149 #ifdef INET
150 	  case AF_INET:
151 #endif
152 #ifdef INET6
153 	  case AF_INET6:
154 #endif
155 	     break;
156 	  default:
157 	     err = EAFNOSUPPORT;
158 	     break;
159 	}
160        /* XXX do we need to do more here for either of these? */
161        break;
162     case SIOCSIFMTU:
163        ifr = (void *) data;
164        ((SOFTC *)intf->if_softc)->intf.if_mtu = ifr->ifr_mtu;
165        break;
166     case SIOCGIFMTU:
167        ifr = (void *) data;
168        ifr->ifr_mtu = intf->if_mtu;
169        break;
170     default:
171        err = EINVAL;
172        break;
173   }
174  splx(s);
175  return(err);
176 }
177 
178 static int srt_if_output(
179 	struct ifnet *intf,
180 	struct mbuf *m,
181 	const struct sockaddr *to,
182 	struct rtentry *rtp )
183 {
184  SOFTC *sc;
185  RT *r;
186 
187  sc = intf->if_softc;
188  if (! (intf->if_flags & IFF_UP))
189   { m_freem(m);
190     return(ENETDOWN);
191   }
192  switch (to->sa_family)
193   {
194 #ifdef INET
195     case AF_INET:
196 #endif
197 	{ struct ip *ip;
198 	  ip = mtod(m,struct ip *);
199 	  r = find_rt(sc,AF_INET,ip->ip_src);
200 	}
201        break;
202 #ifdef INET6
203     case AF_INET6:
204 #endif
205 	{ struct ip6_hdr *ip;
206 	  ip = mtod(m,struct ip6_hdr *);
207 	  r = find_rt(sc,AF_INET6,ip->ip6_src);
208 	}
209        break;
210     default:
211        IF_DROP(&intf->if_snd);
212        m_freem(m);
213        return(EAFNOSUPPORT);
214        break;
215   }
216  /* XXX Do we need to bpf_tap?  Or do higher layers now handle that? */
217  /* if_gif.c seems to imply the latter. */
218  intf->if_opackets ++;
219  if (! r)
220   { intf->if_oerrors ++;
221     m_freem(m);
222     return(0);
223   }
224  if (! (m->m_flags & M_PKTHDR))
225   { printf("srt_if_output no PKTHDR\n");
226     m_freem(m);
227     return(0);
228   }
229  intf->if_obytes += m->m_pkthdr.len;
230  if (! (r->u.dstifp->if_flags & IFF_UP))
231   { m_freem(m);
232     return(0); /* XXX ENETDOWN? */
233   }
234  /* XXX is 0 the right last arg here? */
235  return((*r->u.dstifp->if_output)(r->u.dstifp,m,&r->dst.sa,0));
236 }
237 
238 static int srt_clone_create(struct if_clone *cl, int unit)
239 {
240  SOFTC *sc;
241 
242  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
243  if (softcv[unit]) return(EBUSY);
244  sc = malloc(sizeof(SOFTC),M_DEVBUF,M_WAIT);
245  bzero(&sc->intf,sizeof(sc->intf)); /* XXX */
246  sc->unit = unit;
247  sc->nrt = 0;
248  sc->rts = 0;
249  sc->flags = 0;
250  sc->kflags = 0;
251  snprintf(&sc->intf.if_xname[0],sizeof(sc->intf.if_xname),"%s%d",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 #if NBPFILTER > 0 /* see comment near top */
262  bpfattach(&sc->intf,0/*???*/,0/*???*/);
263 #endif
264  softcv[unit] = sc;
265  return(0);
266 }
267 
268 static int srt_clone_destroy(struct ifnet *intf)
269 {
270  SOFTC *sc;
271 
272  sc = intf->if_softc;
273  if ((intf->if_flags & IFF_UP) || (sc->kflags & SKF_CDEVOPEN)) return(EBUSY);
274 #if NBPFILTER > 0
275  bpfdetach(intf);
276 #endif
277  if_detach(intf);
278  if ((sc->unit < 0) || (sc->unit > SRT_MAXUNIT))
279   { panic("srt_clone_destroy: impossible unit %d\n",sc->unit);
280   }
281  if (softcv[sc->unit] != sc)
282   { panic("srt_clone_destroy: bad backpointer ([%d]=%p not %p)\n",
283 			sc->unit,(void *)softcv[sc->unit],(void *)sc);
284   }
285  softcv[sc->unit] = 0;
286  free(sc,M_DEVBUF);
287  return(0);
288 }
289 
290 struct if_clone srt_clone =
291     IF_CLONE_INITIALIZER("srt",&srt_clone_create,&srt_clone_destroy);
292 
293 extern void srtattach(void);
294 void srtattach(void)
295 {
296  int i;
297 
298  for (i=SRT_MAXUNIT;i>=0;i--) softcv[i] = 0;
299  global_flags = 0;
300  if_clone_attach(&srt_clone);
301 }
302 
303 /* Special-device interface. */
304 
305 static int srt_open(dev_t dev, int flag, int mode, struct lwp *l)
306 {
307  int unit;
308  SOFTC *sc;
309 
310  unit = minor(dev);
311  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
312  sc = softcv[unit];
313  if (! sc) return(ENXIO);
314  sc->kflags |= SKF_CDEVOPEN;
315  return(0);
316 }
317 
318 static int srt_close(dev_t dev, int flag, int mode, struct lwp *l)
319 {
320  int unit;
321  SOFTC *sc;
322 
323  unit = minor(dev);
324  if ((unit < 0) || (unit > SRT_MAXUNIT)) return(ENXIO);
325  sc = softcv[unit];
326  if (! sc) return(ENXIO);
327  sc->kflags &= ~SKF_CDEVOPEN;
328  return(0);
329 }
330 
331 static int srt_ioctl(
332 	dev_t dev,
333 	u_long cmd,
334 	void *data,
335 	int flag,
336 	struct lwp *l )
337 {
338  SOFTC *sc;
339  RT *dr;
340  RT *scr;
341  struct ifnet *intf;
342  char nbuf[IFNAMSIZ];
343 
344  sc = softcv[minor(dev)];
345  if (! sc) panic("srt_ioctl: softc disappeared");
346  switch (cmd)
347   { case SRT_GETNRT:
348        if (! (flag & FREAD)) return(EBADF);
349        *(unsigned int *)data = sc->nrt;
350        return(0);
351        break;
352     case SRT_GETRT:
353        if (! (flag & FREAD)) return(EBADF);
354        dr = (RT *) data;
355        if (dr->inx >= sc->nrt) return(EDOM);
356        scr = sc->rts[dr->inx];
357        dr->af = scr->af;
358        dr->srcmatch = scr->srcmatch;
359        dr->srcmask = scr->srcmask;
360        strncpy(&dr->u.dstifn[0],&scr->u.dstifp->if_xname[0],IFNAMSIZ);
361        memcpy(&dr->dst,&scr->dst,scr->dst.sa.sa_len);
362        return(0);
363        break;
364     case SRT_SETRT:
365        if (! (flag & FWRITE)) return(EBADF);
366        dr = (RT *) data;
367        if (dr->inx > sc->nrt) return(EDOM);
368        strncpy(&nbuf[0],&dr->u.dstifn[0],IFNAMSIZ);
369        nbuf[IFNAMSIZ-1] = '\0';
370        if (dr->dst.sa.sa_family != dr->af) return(EIO);
371        switch (dr->af)
372 	{
373 #ifdef INET
374 	  case AF_INET:
375 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin)) return(EIO);
376 	     if (dr->srcmask > 32) return(EIO);
377 	     break;
378 #endif
379 #ifdef INET6
380 	  case AF_INET6:
381 	     if (dr->dst.sa.sa_len != sizeof(dr->dst.sin6)) return(EIO);
382 	     if (dr->srcmask > 128) return(EIO);
383 	     break;
384 #endif
385 	     break;
386 	  default:
387 	     return(EAFNOSUPPORT);
388 	     break;
389 	}
390        intf = ifunit(&nbuf[0]);
391        if (intf == 0) return(ENXIO); /* needs translation */
392        if (dr->inx == sc->nrt)
393 	{ RT **tmp;
394 	  tmp = malloc((sc->nrt+1)*sizeof(*tmp),M_DEVBUF,M_WAITOK);
395 	  if (tmp == 0) return(ENOBUFS);
396 	  tmp[sc->nrt] = 0;
397 	  if (sc->nrt > 0)
398 	   { memcpy(tmp,sc->rts,sc->nrt*sizeof(*tmp));
399 	     free(sc->rts,M_DEVBUF);
400 	   }
401 	  sc->rts = tmp;
402 	  sc->nrt ++;
403 	}
404        scr = sc->rts[dr->inx];
405        if (scr == 0)
406 	{ scr = malloc(sizeof(RT),M_DEVBUF,M_WAITOK);
407 	  if (scr == 0) return(ENOBUFS);
408 	  scr->inx = dr->inx;
409 	  scr->af = AF_UNSPEC;
410 	  sc->rts[dr->inx] = scr;
411 	}
412        scr->af = dr->af;
413        scr->srcmatch = dr->srcmatch;
414        scr->srcmask = dr->srcmask;
415        scr->u.dstifp = intf;
416        memcpy(&scr->dst,&dr->dst,dr->dst.sa.sa_len);
417        update_mtu(sc);
418        return(0);
419        break;
420     case SRT_DELRT:
421 	{ unsigned int i;
422 	  if (! (flag & FWRITE)) return(EBADF);
423 	  i = *(unsigned int *)data;
424 	  if (i >= sc->nrt) return(EDOM);
425 	  scr = sc->rts[i];
426 	  sc->rts[i] = 0;
427 	  free(scr,M_DEVBUF);
428 	  sc->nrt --;
429 	  if (i < sc->nrt) memcpy(sc->rts+i,sc->rts+i+1,(sc->nrt-i)*sizeof(*sc->rts));
430 	  if (sc->nrt == 0)
431 	   { free(sc->rts,M_DEVBUF);
432 	     sc->rts = 0;
433 	     sc->intf.if_flags &= ~IFF_UP;
434 	   }
435 	}
436        update_mtu(sc);
437        return(0);
438        break;
439     case SRT_SFLAGS:
440 	{ unsigned int f;
441 	  if (! (flag & FWRITE)) return(EBADF);
442 	  f = *(unsigned int *)data & SSF_UCHG;
443 	  global_flags = (global_flags & ~SSF_UCHG) | (f & SSF_GLOBAL);
444 	  sc->flags = (sc->flags & ~SSF_UCHG) | (f & ~SSF_GLOBAL);
445 	}
446        return(0);
447        break;
448     case SRT_GFLAGS:
449        if (! (flag & FREAD)) return(EBADF);
450        *(unsigned int *)data = sc->flags | global_flags;
451        return(0);
452        break;
453     case SRT_SGFLAGS:
454 	{ unsigned int o;
455 	  unsigned int n;
456 	  if ((flag & (FWRITE|FREAD)) != (FWRITE|FREAD)) return(EBADF);
457 	  o = sc->flags | global_flags;
458 	  n = *(unsigned int *)data & SSF_UCHG;
459 	  global_flags = (global_flags & ~SSF_UCHG) | (n & SSF_GLOBAL);
460 	  sc->flags = (sc->flags & ~SSF_UCHG) | (n & ~SSF_GLOBAL);
461 	  *(unsigned int *)data = o;
462 	}
463        return(0);
464        break;
465     case SRT_DEBUG:
466        return(0);
467        break;
468   }
469  return(ENOTTY);
470 }
471 
472 const struct cdevsw srt_cdevsw
473  = { &srt_open,
474      &srt_close,
475      nullread,
476      nullwrite,
477      &srt_ioctl,
478      nullstop,
479      notty,
480      nullpoll,
481      nommap,
482      nullkqfilter,
483      D_OTHER };
484