1 /* 2 * Copyright (c) 1982, 1989 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)if_ethersubr.c 7.15 (Berkeley) 01/30/92 8 */ 9 10 #include "param.h" 11 #include "systm.h" 12 #include "kernel.h" 13 #include "malloc.h" 14 #include "mbuf.h" 15 #include "protosw.h" 16 #include "socket.h" 17 #include "ioctl.h" 18 #include "errno.h" 19 #include "syslog.h" 20 #include "machine/cpu.h" 21 22 #include "if.h" 23 #include "netisr.h" 24 #include "route.h" 25 #include "if_llc.h" 26 #include "if_dl.h" 27 28 #ifdef INET 29 #include "../netinet/in.h" 30 #include "../netinet/in_var.h" 31 #endif 32 #include "../netinet/if_ether.h" 33 34 #ifdef NS 35 #include "../netns/ns.h" 36 #include "../netns/ns_if.h" 37 #endif 38 39 #ifdef ISO 40 #include "../netiso/argo_debug.h" 41 #include "../netiso/iso.h" 42 #include "../netiso/iso_var.h" 43 #include "../netiso/iso_snpac.h" 44 #endif 45 46 u_char etherbroadcastaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 47 extern struct ifnet loif; 48 #define senderr(e) { error = (e); goto bad;} 49 50 /* 51 * Ethernet output routine. 52 * Encapsulate a packet of type family for the local net. 53 * Use trailer local net encapsulation if enough data in first 54 * packet leaves a multiple of 512 bytes of data in remainder. 55 * Assumes that ifp is actually pointer to arpcom structure. 56 */ 57 ether_output(ifp, m0, dst, rt0) 58 register struct ifnet *ifp; 59 struct mbuf *m0; 60 struct sockaddr *dst; 61 struct rtentry *rt0; 62 { 63 short type; 64 int s, error = 0; 65 u_char edst[6]; 66 register struct mbuf *m = m0; 67 register struct rtentry *rt; 68 struct mbuf *mcopy = (struct mbuf *)0; 69 register struct ether_header *eh; 70 int usetrailers, off, len = m->m_pkthdr.len; 71 #define ac ((struct arpcom *)ifp) 72 73 if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) 74 senderr(ENETDOWN); 75 ifp->if_lastchange = time; 76 if (rt = rt0) { 77 if ((rt->rt_flags & RTF_UP) == 0) { 78 if (rt0 = rt = rtalloc1(dst, 1)) 79 rt->rt_refcnt--; 80 else 81 return (EHOSTUNREACH); 82 } 83 if (rt->rt_flags & RTF_GATEWAY) { 84 if (rt->rt_gwroute == 0) 85 goto lookup; 86 if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) { 87 rtfree(rt); rt = rt0; 88 lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1); 89 if ((rt = rt->rt_gwroute) == 0) 90 return (EHOSTUNREACH); 91 } 92 } 93 if (rt->rt_flags & RTF_REJECT) 94 if (rt->rt_rmx.rmx_expire == 0 || 95 time.tv_sec < rt->rt_rmx.rmx_expire) 96 return (rt == rt0 ? EHOSTDOWN : EHOSTUNREACH); 97 } 98 switch (dst->sa_family) { 99 100 #ifdef INET 101 case AF_INET: 102 if (!arpresolve(ac, rt, m, (struct sockaddr_in *)dst, 103 edst, &usetrailers)) 104 return (0); /* if not yet resolved */ 105 if ((ifp->if_flags & IFF_SIMPLEX) && (*edst & 1)) 106 mcopy = m_copy(m, 0, (int)M_COPYALL); 107 off = m->m_pkthdr.len - m->m_len; 108 if (usetrailers && off > 0 && (off & 0x1ff) == 0 && 109 (m->m_flags & M_EXT) == 0 && 110 m->m_data >= m->m_pktdat + 2 * sizeof (u_short)) { 111 type = ETHERTYPE_TRAIL + (off>>9); 112 m->m_data -= 2 * sizeof (u_short); 113 m->m_len += 2 * sizeof (u_short); 114 len += 2 * sizeof (u_short); 115 *mtod(m, u_short *) = htons((u_short)ETHERTYPE_IP); 116 *(mtod(m, u_short *) + 1) = htons((u_short)m->m_len); 117 goto gottrailertype; 118 } 119 type = ETHERTYPE_IP; 120 goto gottype; 121 #endif 122 #ifdef NS 123 case AF_NS: 124 type = ETHERTYPE_NS; 125 bcopy((caddr_t)&(((struct sockaddr_ns *)dst)->sns_addr.x_host), 126 (caddr_t)edst, sizeof (edst)); 127 if (!bcmp((caddr_t)edst, (caddr_t)&ns_thishost, sizeof(edst))) 128 return (looutput(ifp, m, dst, rt)); 129 if ((ifp->if_flags & IFF_SIMPLEX) && (*edst & 1)) 130 mcopy = m_copy(m, 0, (int)M_COPYALL); 131 goto gottype; 132 #endif 133 #ifdef ISO 134 case AF_ISO: { 135 int snpalen; 136 struct llc *l; 137 register struct sockaddr_dl *sdl; 138 139 if (rt && (sdl = (struct sockaddr_dl *)rt->rt_gateway) && 140 sdl->sdl_family == AF_LINK && sdl->sdl_alen > 0) { 141 bcopy(LLADDR(sdl), (caddr_t)edst, sizeof(edst)); 142 } else if (error = 143 iso_snparesolve(ifp, (struct sockaddr_iso *)dst, 144 (char *)edst, &snpalen)) 145 goto bad; /* Not Resolved */ 146 if ((ifp->if_flags & IFF_SIMPLEX) && (*edst & 1) && 147 (mcopy = m_copy(m, 0, (int)M_COPYALL))) { 148 M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT); 149 if (mcopy) { 150 eh = mtod(mcopy, struct ether_header *); 151 bcopy((caddr_t)edst, 152 (caddr_t)eh->ether_dhost, sizeof (edst)); 153 bcopy((caddr_t)ac->ac_enaddr, 154 (caddr_t)eh->ether_shost, sizeof (edst)); 155 } 156 } 157 M_PREPEND(m, 3, M_DONTWAIT); 158 if (m == NULL) 159 return (0); 160 type = m->m_pkthdr.len; 161 l = mtod(m, struct llc *); 162 l->llc_dsap = l->llc_ssap = LLC_ISO_LSAP; 163 l->llc_control = LLC_UI; 164 len += 3; 165 IFDEBUG(D_ETHER) 166 int i; 167 printf("unoutput: sending pkt to: "); 168 for (i=0; i<6; i++) 169 printf("%x ", edst[i] & 0xff); 170 printf("\n"); 171 ENDDEBUG 172 } goto gottype; 173 #endif ISO 174 #ifdef RMP 175 case AF_RMP: 176 /* 177 * This is IEEE 802.3 -- the Ethernet `type' field is 178 * really a `length' field. 179 */ 180 type = m->m_len; 181 bcopy((caddr_t)dst->sa_data, (caddr_t)edst, sizeof(edst)); 182 break; 183 #endif 184 185 case AF_UNSPEC: 186 eh = (struct ether_header *)dst->sa_data; 187 bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, sizeof (edst)); 188 type = eh->ether_type; 189 goto gottype; 190 191 default: 192 printf("%s%d: can't handle af%d\n", ifp->if_name, ifp->if_unit, 193 dst->sa_family); 194 senderr(EAFNOSUPPORT); 195 } 196 197 gottrailertype: 198 /* 199 * Packet to be sent as trailer: move first packet 200 * (control information) to end of chain. 201 */ 202 while (m->m_next) 203 m = m->m_next; 204 m->m_next = m0; 205 m = m0->m_next; 206 m0->m_next = 0; 207 208 gottype: 209 if (mcopy) 210 (void) looutput(ifp, mcopy, dst, rt); 211 /* 212 * Add local net header. If no space in first mbuf, 213 * allocate another. 214 */ 215 M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT); 216 if (m == 0) 217 senderr(ENOBUFS); 218 eh = mtod(m, struct ether_header *); 219 type = htons((u_short)type); 220 bcopy((caddr_t)&type,(caddr_t)&eh->ether_type, 221 sizeof(eh->ether_type)); 222 bcopy((caddr_t)edst, (caddr_t)eh->ether_dhost, sizeof (edst)); 223 bcopy((caddr_t)ac->ac_enaddr, (caddr_t)eh->ether_shost, 224 sizeof(eh->ether_shost)); 225 s = splimp(); 226 /* 227 * Queue message on interface, and start output if interface 228 * not yet active. 229 */ 230 if (IF_QFULL(&ifp->if_snd)) { 231 IF_DROP(&ifp->if_snd); 232 splx(s); 233 senderr(ENOBUFS); 234 } 235 IF_ENQUEUE(&ifp->if_snd, m); 236 if ((ifp->if_flags & IFF_OACTIVE) == 0) 237 (*ifp->if_start)(ifp); 238 splx(s); 239 ifp->if_obytes += len + sizeof (struct ether_header); 240 if (edst[0] & 1) 241 ifp->if_omcasts++; 242 return (error); 243 244 bad: 245 if (m) 246 m_freem(m); 247 return (error); 248 } 249 250 /* 251 * Process a received Ethernet packet; 252 * the packet is in the mbuf chain m without 253 * the ether header, which is provided separately. 254 */ 255 ether_input(ifp, eh, m) 256 struct ifnet *ifp; 257 register struct ether_header *eh; 258 struct mbuf *m; 259 { 260 register struct ifqueue *inq; 261 register struct llc *l; 262 int s; 263 264 ifp->if_lastchange = time; 265 ifp->if_ibytes += m->m_pkthdr.len + sizeof (*eh); 266 if (bcmp((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost, 267 sizeof(etherbroadcastaddr)) == 0) 268 m->m_flags |= M_BCAST; 269 else if (eh->ether_dhost[0] & 1) 270 m->m_flags |= M_MCAST; 271 if (m->m_flags & (M_BCAST|M_MCAST)) 272 ifp->if_imcasts++; 273 274 switch (eh->ether_type) { 275 #ifdef INET 276 case ETHERTYPE_IP: 277 schednetisr(NETISR_IP); 278 inq = &ipintrq; 279 break; 280 281 case ETHERTYPE_ARP: 282 schednetisr(NETISR_ARP); 283 inq = &arpintrq; 284 break; 285 #endif 286 #ifdef NS 287 case ETHERTYPE_NS: 288 schednetisr(NETISR_NS); 289 inq = &nsintrq; 290 break; 291 292 #endif 293 default: 294 #ifdef ISO 295 if (eh->ether_type > ETHERMTU) 296 goto dropanyway; 297 l = mtod(m, struct llc *); 298 switch (l->llc_control) { 299 case LLC_UI: 300 /* LLC_UI_P forbidden in class 1 service */ 301 if ((l->llc_dsap == LLC_ISO_LSAP) && 302 (l->llc_ssap == LLC_ISO_LSAP)) { 303 /* LSAP for ISO */ 304 if (m->m_pkthdr.len > eh->ether_type) 305 m_adj(m, eh->ether_type - m->m_pkthdr.len); 306 m->m_data += 3; /* XXX */ 307 m->m_len -= 3; /* XXX */ 308 m->m_pkthdr.len -= 3; /* XXX */ 309 M_PREPEND(m, sizeof *eh, M_DONTWAIT); 310 if (m == 0) 311 return; 312 *mtod(m, struct ether_header *) = *eh; 313 IFDEBUG(D_ETHER) 314 printf("clnp packet"); 315 ENDDEBUG 316 schednetisr(NETISR_ISO); 317 inq = &clnlintrq; 318 break; 319 } 320 goto dropanyway; 321 322 case LLC_XID: 323 case LLC_XID_P: 324 if(m->m_len < 6) 325 goto dropanyway; 326 l->llc_window = 0; 327 l->llc_fid = 9; 328 l->llc_class = 1; 329 l->llc_dsap = l->llc_ssap = 0; 330 /* Fall through to */ 331 case LLC_TEST: 332 case LLC_TEST_P: 333 { 334 struct sockaddr sa; 335 register struct ether_header *eh2; 336 int i; 337 u_char c = l->llc_dsap; 338 l->llc_dsap = l->llc_ssap; 339 l->llc_ssap = c; 340 if (m->m_flags & (M_BCAST | M_MCAST)) 341 bcopy((caddr_t)ac->ac_enaddr, 342 (caddr_t)eh->ether_dhost, 6); 343 sa.sa_family = AF_UNSPEC; 344 sa.sa_len = sizeof(sa); 345 eh2 = (struct ether_header *)sa.sa_data; 346 for (i = 0; i < 6; i++) { 347 eh2->ether_shost[i] = c = eh->ether_dhost[i]; 348 eh2->ether_dhost[i] = 349 eh->ether_dhost[i] = eh->ether_shost[i]; 350 eh->ether_shost[i] = c; 351 } 352 ifp->if_output(ifp, m, &sa); 353 return; 354 } 355 dropanyway: 356 default: 357 m_freem(m); 358 return; 359 } 360 #else 361 m_freem(m); 362 return; 363 #endif ISO 364 } 365 366 s = splimp(); 367 if (IF_QFULL(inq)) { 368 IF_DROP(inq); 369 m_freem(m); 370 } else 371 IF_ENQUEUE(inq, m); 372 splx(s); 373 } 374 375 /* 376 * Convert Ethernet address to printable (loggable) representation. 377 */ 378 static char digits[] = "0123456789abcdef"; 379 char * 380 ether_sprintf(ap) 381 register u_char *ap; 382 { 383 register i; 384 static char etherbuf[18]; 385 register char *cp = etherbuf; 386 387 for (i = 0; i < 6; i++) { 388 *cp++ = digits[*ap >> 4]; 389 *cp++ = digits[*ap++ & 0xf]; 390 *cp++ = ':'; 391 } 392 *--cp = 0; 393 return (etherbuf); 394 } 395