1 /* $NetBSD: getether.c,v 1.6 2002/07/14 00:30:02 wiz Exp $ */ 2 3 #include <sys/cdefs.h> 4 #ifndef lint 5 __RCSID("$NetBSD: getether.c,v 1.6 2002/07/14 00:30:02 wiz 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 extern int getether(char *, char *); 30 31 #if defined(ultrix) || (defined(__osf__) && defined(__alpha)) 32 /* 33 * This is really easy on Ultrix! Thanks to 34 * Harald Lundberg <hl@tekla.fi> for this code. 35 * 36 * The code here is not specific to the Alpha, but that was the 37 * only symbol we could find to identify DEC's version of OSF. 38 * (Perhaps we should just define DEC in the Makefile... -gwr) 39 */ 40 41 #include <sys/ioctl.h> 42 #include <net/if.h> /* struct ifdevea */ 43 44 int 45 getether(char *ifname, char *eap) 46 { 47 int rc = -1; 48 int fd; 49 struct ifdevea phys; 50 bzero(&phys, sizeof(phys)); 51 strcpy(phys.ifr_name, ifname); 52 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 53 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 54 return -1; 55 } 56 if (ioctl(fd, SIOCRPHYSADDR, &phys) < 0) { 57 report(LOG_ERR, "getether: ioctl SIOCRPHYSADDR failed"); 58 } else { 59 bcopy(&phys.current_pa[0], eap, EALEN); 60 rc = 0; 61 } 62 close(fd); 63 return rc; 64 } 65 66 #define GETETHER 67 #endif /* ultrix|osf1 */ 68 69 70 #ifdef SUNOS 71 72 #include <sys/sockio.h> 73 #include <sys/time.h> /* needed by net_if.h */ 74 #include <net/nit_if.h> /* for NIOCBIND */ 75 #include <net/if.h> /* for struct ifreq */ 76 77 /* ifname: interface name from ifconfig structure */ 78 /* eap: Ether address (output) */ 79 getether(char *ifname, char *eap) 80 { 81 int rc = -1; 82 83 struct ifreq ifrnit; 84 int nit; 85 86 bzero((char *) &ifrnit, sizeof(ifrnit)); 87 strncpy(&ifrnit.ifr_name[0], ifname, IFNAMSIZ); 88 89 nit = open("/dev/nit", 0); 90 if (nit < 0) { 91 report(LOG_ERR, "getether: open /dev/nit: %s", 92 get_errmsg()); 93 return rc; 94 } 95 do { 96 if (ioctl(nit, NIOCBIND, &ifrnit) < 0) { 97 report(LOG_ERR, "getether: NIOCBIND on nit"); 98 break; 99 } 100 if (ioctl(nit, SIOCGIFADDR, &ifrnit) < 0) { 101 report(LOG_ERR, "getether: SIOCGIFADDR on nit"); 102 break; 103 } 104 bcopy(&ifrnit.ifr_addr.sa_data[0], eap, EALEN); 105 rc = 0; 106 } while (0); 107 close(nit); 108 return rc; 109 } 110 111 #define GETETHER 112 #endif /* SUNOS */ 113 114 115 #if defined(__386BSD__) || defined(__NetBSD__) 116 /* Thanks to John Brezak <brezak@ch.hp.com> for this code. */ 117 #include <sys/ioctl.h> 118 #include <net/if.h> 119 #include <net/if_dl.h> 120 #include <net/if_types.h> 121 122 /* ifname: interface name from ifconfig structure */ 123 /* eap: Ether address (output) */ 124 int 125 getether(char *ifname, char *eap) 126 { 127 int fd, rc = -1; 128 int n; 129 struct ifreq ibuf[16]; 130 struct ifconf ifc; 131 struct ifreq *ifrp, *ifend; 132 133 /* Fetch the interface configuration */ 134 fd = socket(AF_INET, SOCK_DGRAM, 0); 135 if (fd < 0) { 136 report(LOG_ERR, "getether: socket %s: %s", ifname, get_errmsg()); 137 return (fd); 138 } 139 ifc.ifc_len = sizeof(ibuf); 140 ifc.ifc_buf = (caddr_t) ibuf; 141 if (ioctl(fd, SIOCGIFCONF, (char *) &ifc) < 0 || 142 ifc.ifc_len < sizeof(struct ifreq)) { 143 report(LOG_ERR, "getether: SIOCGIFCONF: %s", get_errmsg()); 144 goto out; 145 } 146 /* Search interface configuration list for link layer address. */ 147 ifrp = ibuf; 148 ifend = (struct ifreq *) ((char *) ibuf + ifc.ifc_len); 149 while (ifrp < ifend) { 150 /* Look for interface */ 151 if (strcmp(ifname, ifrp->ifr_name) == 0 && 152 ifrp->ifr_addr.sa_family == AF_LINK && 153 ((struct sockaddr_dl *) &ifrp->ifr_addr)->sdl_type == IFT_ETHER) { 154 bcopy(LLADDR((struct sockaddr_dl *) &ifrp->ifr_addr), eap, EALEN); 155 rc = 0; 156 break; 157 } 158 /* Bump interface config pointer */ 159 n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); 160 if (n < sizeof(*ifrp)) 161 n = sizeof(*ifrp); 162 ifrp = (struct ifreq *) ((char *) ifrp + n); 163 } 164 165 out: 166 close(fd); 167 return (rc); 168 } 169 170 #define GETETHER 171 #endif /* __NetBSD__ */ 172 173 174 #ifdef SVR4 175 /* 176 * This is for "Streams TCP/IP" by Lachman Associates. 177 * They sure made this cumbersome! -gwr 178 */ 179 180 #include <sys/sockio.h> 181 #include <sys/dlpi.h> 182 #include <stropts.h> 183 #ifndef NULL 184 #define NULL 0 185 #endif 186 187 /* ifname: interface name from ifconfig structure */ 188 /* eap: Ether address (output) */ 189 getether(char *ifname, char *eap) 190 { 191 int rc = -1; 192 char devname[32]; 193 char tmpbuf[sizeof(union DL_primitives) + 16]; 194 struct strbuf cbuf; 195 int fd, flags; 196 union DL_primitives *dlp; 197 char *enaddr; 198 int unit = -1; /* which unit to attach */ 199 200 sprintf(devname, "/dev/%s", ifname); 201 fd = open(devname, 2); 202 if (fd < 0) { 203 /* Try without the trailing digit. */ 204 char *p = devname + 5; 205 while (isalpha(*p)) 206 p++; 207 if (isdigit(*p)) { 208 unit = *p - '0'; 209 *p = '\0'; 210 } 211 fd = open(devname, 2); 212 if (fd < 0) { 213 report(LOG_ERR, "getether: open %s: %s", 214 devname, get_errmsg()); 215 return rc; 216 } 217 } 218 #ifdef DL_ATTACH_REQ 219 /* 220 * If this is a "Style 2" DLPI, then we must "attach" first 221 * to tell the driver which unit (board, port) we want. 222 * For now, decide this based on the device name. 223 * (Should do "info_req" and check dl_provider_style ...) 224 */ 225 if (unit >= 0) { 226 memset(tmpbuf, 0, sizeof(tmpbuf)); 227 dlp = (union DL_primitives *) tmpbuf; 228 dlp->dl_primitive = DL_ATTACH_REQ; 229 dlp->attach_req.dl_ppa = unit; 230 cbuf.buf = tmpbuf; 231 cbuf.len = DL_ATTACH_REQ_SIZE; 232 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 233 report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg()); 234 goto out; 235 } 236 /* Recv the ack. */ 237 cbuf.buf = tmpbuf; 238 cbuf.maxlen = sizeof(tmpbuf); 239 flags = 0; 240 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 241 report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg()); 242 goto out; 243 } 244 /* 245 * Check the type, etc. 246 */ 247 if (dlp->dl_primitive == DL_ERROR_ACK) { 248 report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d", 249 dlp->error_ack.dl_errno, 250 dlp->error_ack.dl_unix_errno); 251 goto out; 252 } 253 if (dlp->dl_primitive != DL_OK_ACK) { 254 report(LOG_ERR, "getether: attach: not OK or ERROR"); 255 goto out; 256 } 257 } /* unit >= 0 */ 258 #endif /* DL_ATTACH_REQ */ 259 260 /* 261 * Get the Ethernet address the same way the ARP module 262 * does when it is pushed onto a new stream (bind). 263 * One should instead be able just do an dl_info_req 264 * but many drivers do not supply the hardware address 265 * in the response to dl_info_req (they MUST supply it 266 * for dl_bind_ack because the ARP module requires it). 267 */ 268 memset(tmpbuf, 0, sizeof(tmpbuf)); 269 dlp = (union DL_primitives *) tmpbuf; 270 dlp->dl_primitive = DL_BIND_REQ; 271 dlp->bind_req.dl_sap = 0x8FF; /* XXX - Unused SAP */ 272 cbuf.buf = tmpbuf; 273 cbuf.len = DL_BIND_REQ_SIZE; 274 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 275 report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg()); 276 goto out; 277 } 278 /* Recv the ack. */ 279 cbuf.buf = tmpbuf; 280 cbuf.maxlen = sizeof(tmpbuf); 281 flags = 0; 282 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 283 report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg()); 284 goto out; 285 } 286 /* 287 * Check the type, etc. 288 */ 289 if (dlp->dl_primitive == DL_ERROR_ACK) { 290 report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d", 291 dlp->error_ack.dl_errno, 292 dlp->error_ack.dl_unix_errno); 293 goto out; 294 } 295 if (dlp->dl_primitive != DL_BIND_ACK) { 296 report(LOG_ERR, "getether: bind: not OK or ERROR"); 297 goto out; 298 } 299 if (dlp->bind_ack.dl_addr_offset == 0) { 300 report(LOG_ERR, "getether: bind: ack has no address"); 301 goto out; 302 } 303 if (dlp->bind_ack.dl_addr_length < EALEN) { 304 report(LOG_ERR, "getether: bind: ack address truncated"); 305 goto out; 306 } 307 /* 308 * Copy the Ethernet address out of the message. 309 */ 310 enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset; 311 memcpy(eap, enaddr, EALEN); 312 rc = 0; 313 314 out: 315 close(fd); 316 return rc; 317 } 318 319 #define GETETHER 320 #endif /* SVR4 */ 321 322 323 #ifdef linux 324 /* 325 * This is really easy on Linux! This version (for linux) 326 * written by Nigel Metheringham <nigelm@ohm.york.ac.uk> 327 * 328 * The code is almost identical to the Ultrix code - however 329 * the names are different to confuse the innocent :-) 330 * Most of this code was stolen from the Ultrix bit above. 331 */ 332 333 #include <sys/ioctl.h> 334 #include <net/if.h> /* struct ifreq */ 335 336 /* In a properly configured system this should be either sys/socketio.h 337 or sys/sockios.h, but on my distribution these don't line up correctly */ 338 #include <linux/sockios.h> /* Needed for IOCTL defs */ 339 340 getether(char *ifname, char *eap) 341 { 342 int rc = -1; 343 int fd; 344 struct ifreq phys; 345 bzero(&phys, sizeof(phys)); 346 strcpy(phys.ifr_name, ifname); 347 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 348 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 349 return -1; 350 } 351 if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) { 352 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed"); 353 } else { 354 bcopy(phys.ifr_hwaddr, eap, EALEN); 355 rc = 0; 356 } 357 close(fd); 358 return rc; 359 } 360 361 #define GETETHER 362 #endif /* linux */ 363 364 365 /* If we don't know how on this system, just return an error. */ 366 #ifndef GETETHER 367 getether(char *ifname, char *eap) 368 { 369 return -1; 370 } 371 372 #endif /* !GETETHER */ 373 374 /* 375 * Local Variables: 376 * tab-width: 4 377 * c-indent-level: 4 378 * c-argdecl-indent: 4 379 * c-continued-statement-offset: 4 380 * c-continued-brace-offset: -4 381 * c-label-offset: -4 382 * c-brace-offset: 0 383 * End: 384 */ 385