1 /* $NetBSD: getether.c,v 1.4 2000/10/11 20:23:49 is Exp $ */ 2 3 #include <sys/cdefs.h> 4 #ifndef lint 5 __RCSID("$NetBSD: getether.c,v 1.4 2000/10/11 20:23:49 is Exp $"); 6 #endif 7 8 /* 9 * getether.c : get the ethernet address of an interface 10 * 11 * All of this code is quite system-specific. As you may well 12 * guess, it took a good bit of detective work to figure out! 13 * 14 * If you figure out how to do this on another system, 15 * please let me know. <gwr@mc.com> 16 */ 17 18 #include <sys/types.h> 19 #include <sys/socket.h> 20 21 #include <ctype.h> 22 #include <string.h> 23 #include <syslog.h> 24 #include <unistd.h> 25 26 #include "report.h" 27 #define EALEN 6 28 29 #ifdef __STDC__ 30 #define P(args) args 31 #else 32 #define P(args) () 33 #endif 34 35 extern int getether P((char *, char *)); 36 37 #undef P 38 39 #if defined(ultrix) || (defined(__osf__) && defined(__alpha)) 40 /* 41 * This is really easy on Ultrix! Thanks to 42 * Harald Lundberg <hl@tekla.fi> for this code. 43 * 44 * The code here is not specific to the Alpha, but that was the 45 * only symbol we could find to identify DEC's version of OSF. 46 * (Perhaps we should just define DEC in the Makefile... -gwr) 47 */ 48 49 #include <sys/ioctl.h> 50 #include <net/if.h> /* struct ifdevea */ 51 52 int 53 getether(ifname, eap) 54 char *ifname, *eap; 55 { 56 int rc = -1; 57 int fd; 58 struct ifdevea phys; 59 bzero(&phys, sizeof(phys)); 60 strcpy(phys.ifr_name, ifname); 61 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 62 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 63 return -1; 64 } 65 if (ioctl(fd, SIOCRPHYSADDR, &phys) < 0) { 66 report(LOG_ERR, "getether: ioctl SIOCRPHYSADDR failed"); 67 } else { 68 bcopy(&phys.current_pa[0], eap, EALEN); 69 rc = 0; 70 } 71 close(fd); 72 return rc; 73 } 74 75 #define GETETHER 76 #endif /* ultrix|osf1 */ 77 78 79 #ifdef SUNOS 80 81 #include <sys/sockio.h> 82 #include <sys/time.h> /* needed by net_if.h */ 83 #include <net/nit_if.h> /* for NIOCBIND */ 84 #include <net/if.h> /* for struct ifreq */ 85 86 getether(ifname, eap) 87 char *ifname; /* interface name from ifconfig structure */ 88 char *eap; /* Ether address (output) */ 89 { 90 int rc = -1; 91 92 struct ifreq ifrnit; 93 int nit; 94 95 bzero((char *) &ifrnit, sizeof(ifrnit)); 96 strncpy(&ifrnit.ifr_name[0], ifname, IFNAMSIZ); 97 98 nit = open("/dev/nit", 0); 99 if (nit < 0) { 100 report(LOG_ERR, "getether: open /dev/nit: %s", 101 get_errmsg()); 102 return rc; 103 } 104 do { 105 if (ioctl(nit, NIOCBIND, &ifrnit) < 0) { 106 report(LOG_ERR, "getether: NIOCBIND on nit"); 107 break; 108 } 109 if (ioctl(nit, SIOCGIFADDR, &ifrnit) < 0) { 110 report(LOG_ERR, "getether: SIOCGIFADDR on nit"); 111 break; 112 } 113 bcopy(&ifrnit.ifr_addr.sa_data[0], eap, EALEN); 114 rc = 0; 115 } while (0); 116 close(nit); 117 return rc; 118 } 119 120 #define GETETHER 121 #endif /* SUNOS */ 122 123 124 #if defined(__386BSD__) || defined(__NetBSD__) 125 /* Thanks to John Brezak <brezak@ch.hp.com> for this code. */ 126 #include <sys/ioctl.h> 127 #include <net/if.h> 128 #include <net/if_dl.h> 129 #include <net/if_types.h> 130 131 int 132 getether(ifname, eap) 133 char *ifname; /* interface name from ifconfig structure */ 134 char *eap; /* Ether address (output) */ 135 { 136 int fd, rc = -1; 137 register int n; 138 struct ifreq ibuf[16]; 139 struct ifconf ifc; 140 register struct ifreq *ifrp, *ifend; 141 142 /* Fetch the interface configuration */ 143 fd = socket(AF_INET, SOCK_DGRAM, 0); 144 if (fd < 0) { 145 report(LOG_ERR, "getether: socket %s: %s", ifname, get_errmsg()); 146 return (fd); 147 } 148 ifc.ifc_len = sizeof(ibuf); 149 ifc.ifc_buf = (caddr_t) ibuf; 150 if (ioctl(fd, SIOCGIFCONF, (char *) &ifc) < 0 || 151 ifc.ifc_len < sizeof(struct ifreq)) { 152 report(LOG_ERR, "getether: SIOCGIFCONF: %s", get_errmsg()); 153 goto out; 154 } 155 /* Search interface configuration list for link layer address. */ 156 ifrp = ibuf; 157 ifend = (struct ifreq *) ((char *) ibuf + ifc.ifc_len); 158 while (ifrp < ifend) { 159 /* Look for interface */ 160 if (strcmp(ifname, ifrp->ifr_name) == 0 && 161 ifrp->ifr_addr.sa_family == AF_LINK && 162 ((struct sockaddr_dl *) &ifrp->ifr_addr)->sdl_type == IFT_ETHER) { 163 bcopy(LLADDR((struct sockaddr_dl *) &ifrp->ifr_addr), eap, EALEN); 164 rc = 0; 165 break; 166 } 167 /* Bump interface config pointer */ 168 n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); 169 if (n < sizeof(*ifrp)) 170 n = sizeof(*ifrp); 171 ifrp = (struct ifreq *) ((char *) ifrp + n); 172 } 173 174 out: 175 close(fd); 176 return (rc); 177 } 178 179 #define GETETHER 180 #endif /* __NetBSD__ */ 181 182 183 #ifdef SVR4 184 /* 185 * This is for "Streams TCP/IP" by Lachman Associates. 186 * They sure made this cumbersome! -gwr 187 */ 188 189 #include <sys/sockio.h> 190 #include <sys/dlpi.h> 191 #include <stropts.h> 192 #ifndef NULL 193 #define NULL 0 194 #endif 195 196 getether(ifname, eap) 197 char *ifname; /* interface name from ifconfig structure */ 198 char *eap; /* Ether address (output) */ 199 { 200 int rc = -1; 201 char devname[32]; 202 char tmpbuf[sizeof(union DL_primitives) + 16]; 203 struct strbuf cbuf; 204 int fd, flags; 205 union DL_primitives *dlp; 206 char *enaddr; 207 int unit = -1; /* which unit to attach */ 208 209 sprintf(devname, "/dev/%s", ifname); 210 fd = open(devname, 2); 211 if (fd < 0) { 212 /* Try without the trailing digit. */ 213 char *p = devname + 5; 214 while (isalpha(*p)) 215 p++; 216 if (isdigit(*p)) { 217 unit = *p - '0'; 218 *p = '\0'; 219 } 220 fd = open(devname, 2); 221 if (fd < 0) { 222 report(LOG_ERR, "getether: open %s: %s", 223 devname, get_errmsg()); 224 return rc; 225 } 226 } 227 #ifdef DL_ATTACH_REQ 228 /* 229 * If this is a "Style 2" DLPI, then we must "attach" first 230 * to tell the driver which unit (board, port) we want. 231 * For now, decide this based on the device name. 232 * (Should do "info_req" and check dl_provider_style ...) 233 */ 234 if (unit >= 0) { 235 memset(tmpbuf, 0, sizeof(tmpbuf)); 236 dlp = (union DL_primitives *) tmpbuf; 237 dlp->dl_primitive = DL_ATTACH_REQ; 238 dlp->attach_req.dl_ppa = unit; 239 cbuf.buf = tmpbuf; 240 cbuf.len = DL_ATTACH_REQ_SIZE; 241 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 242 report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg()); 243 goto out; 244 } 245 /* Recv the ack. */ 246 cbuf.buf = tmpbuf; 247 cbuf.maxlen = sizeof(tmpbuf); 248 flags = 0; 249 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 250 report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg()); 251 goto out; 252 } 253 /* 254 * Check the type, etc. 255 */ 256 if (dlp->dl_primitive == DL_ERROR_ACK) { 257 report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d", 258 dlp->error_ack.dl_errno, 259 dlp->error_ack.dl_unix_errno); 260 goto out; 261 } 262 if (dlp->dl_primitive != DL_OK_ACK) { 263 report(LOG_ERR, "getether: attach: not OK or ERROR"); 264 goto out; 265 } 266 } /* unit >= 0 */ 267 #endif /* DL_ATTACH_REQ */ 268 269 /* 270 * Get the Ethernet address the same way the ARP module 271 * does when it is pushed onto a new stream (bind). 272 * One should instead be able just do an dl_info_req 273 * but many drivers do not supply the hardware address 274 * in the response to dl_info_req (they MUST supply it 275 * for dl_bind_ack because the ARP module requires it). 276 */ 277 memset(tmpbuf, 0, sizeof(tmpbuf)); 278 dlp = (union DL_primitives *) tmpbuf; 279 dlp->dl_primitive = DL_BIND_REQ; 280 dlp->bind_req.dl_sap = 0x8FF; /* XXX - Unused SAP */ 281 cbuf.buf = tmpbuf; 282 cbuf.len = DL_BIND_REQ_SIZE; 283 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 284 report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg()); 285 goto out; 286 } 287 /* Recv the ack. */ 288 cbuf.buf = tmpbuf; 289 cbuf.maxlen = sizeof(tmpbuf); 290 flags = 0; 291 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 292 report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg()); 293 goto out; 294 } 295 /* 296 * Check the type, etc. 297 */ 298 if (dlp->dl_primitive == DL_ERROR_ACK) { 299 report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d", 300 dlp->error_ack.dl_errno, 301 dlp->error_ack.dl_unix_errno); 302 goto out; 303 } 304 if (dlp->dl_primitive != DL_BIND_ACK) { 305 report(LOG_ERR, "getether: bind: not OK or ERROR"); 306 goto out; 307 } 308 if (dlp->bind_ack.dl_addr_offset == 0) { 309 report(LOG_ERR, "getether: bind: ack has no address"); 310 goto out; 311 } 312 if (dlp->bind_ack.dl_addr_length < EALEN) { 313 report(LOG_ERR, "getether: bind: ack address truncated"); 314 goto out; 315 } 316 /* 317 * Copy the Ethernet address out of the message. 318 */ 319 enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset; 320 memcpy(eap, enaddr, EALEN); 321 rc = 0; 322 323 out: 324 close(fd); 325 return rc; 326 } 327 328 #define GETETHER 329 #endif /* SVR4 */ 330 331 332 #ifdef linux 333 /* 334 * This is really easy on Linux! This version (for linux) 335 * written by Nigel Metheringham <nigelm@ohm.york.ac.uk> 336 * 337 * The code is almost identical to the Ultrix code - however 338 * the names are different to confuse the innocent :-) 339 * Most of this code was stolen from the Ultrix bit above. 340 */ 341 342 #include <sys/ioctl.h> 343 #include <net/if.h> /* struct ifreq */ 344 345 /* In a properly configured system this should be either sys/socketio.h 346 or sys/sockios.h, but on my distribution these don't line up correctly */ 347 #include <linux/sockios.h> /* Needed for IOCTL defs */ 348 349 getether(ifname, eap) 350 char *ifname, *eap; 351 { 352 int rc = -1; 353 int fd; 354 struct ifreq phys; 355 bzero(&phys, sizeof(phys)); 356 strcpy(phys.ifr_name, ifname); 357 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 358 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 359 return -1; 360 } 361 if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) { 362 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed"); 363 } else { 364 bcopy(phys.ifr_hwaddr, eap, EALEN); 365 rc = 0; 366 } 367 close(fd); 368 return rc; 369 } 370 371 #define GETETHER 372 #endif /* linux */ 373 374 375 /* If we don't know how on this system, just return an error. */ 376 #ifndef GETETHER 377 getether(ifname, eap) 378 char *ifname, *eap; 379 { 380 return -1; 381 } 382 383 #endif /* !GETETHER */ 384 385 /* 386 * Local Variables: 387 * tab-width: 4 388 * c-indent-level: 4 389 * c-argdecl-indent: 4 390 * c-continued-statement-offset: 4 391 * c-continued-brace-offset: -4 392 * c-label-offset: -4 393 * c-brace-offset: 0 394 * End: 395 */ 396