1 /* $NetBSD: getether.c,v 1.7 2003/07/14 08:36:34 itojun Exp $ */ 2 3 #include <sys/cdefs.h> 4 #ifndef lint 5 __RCSID("$NetBSD: getether.c,v 1.7 2003/07/14 08:36:34 itojun 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 51 bzero(&phys, sizeof(phys)); 52 strncpy(phys.ifr_name, ifname, sizeof(phys.ifr_name)); 53 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 54 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 55 return -1; 56 } 57 if (ioctl(fd, SIOCRPHYSADDR, &phys) < 0) { 58 report(LOG_ERR, "getether: ioctl SIOCRPHYSADDR failed"); 59 } else { 60 bcopy(&phys.current_pa[0], eap, EALEN); 61 rc = 0; 62 } 63 close(fd); 64 return rc; 65 } 66 67 #define GETETHER 68 #endif /* ultrix|osf1 */ 69 70 71 #ifdef SUNOS 72 73 #include <sys/sockio.h> 74 #include <sys/time.h> /* needed by net_if.h */ 75 #include <net/nit_if.h> /* for NIOCBIND */ 76 #include <net/if.h> /* for struct ifreq */ 77 78 /* ifname: interface name from ifconfig structure */ 79 /* eap: Ether address (output) */ 80 getether(char *ifname, char *eap) 81 { 82 int rc = -1; 83 84 struct ifreq ifrnit; 85 int nit; 86 87 bzero((char *) &ifrnit, sizeof(ifrnit)); 88 strncpy(&ifrnit.ifr_name[0], ifname, IFNAMSIZ); 89 90 nit = open("/dev/nit", 0); 91 if (nit < 0) { 92 report(LOG_ERR, "getether: open /dev/nit: %s", 93 get_errmsg()); 94 return rc; 95 } 96 do { 97 if (ioctl(nit, NIOCBIND, &ifrnit) < 0) { 98 report(LOG_ERR, "getether: NIOCBIND on nit"); 99 break; 100 } 101 if (ioctl(nit, SIOCGIFADDR, &ifrnit) < 0) { 102 report(LOG_ERR, "getether: SIOCGIFADDR on nit"); 103 break; 104 } 105 bcopy(&ifrnit.ifr_addr.sa_data[0], eap, EALEN); 106 rc = 0; 107 } while (0); 108 close(nit); 109 return rc; 110 } 111 112 #define GETETHER 113 #endif /* SUNOS */ 114 115 116 #if defined(__386BSD__) || defined(__NetBSD__) 117 /* Thanks to John Brezak <brezak@ch.hp.com> for this code. */ 118 #include <sys/ioctl.h> 119 #include <net/if.h> 120 #include <net/if_dl.h> 121 #include <net/if_types.h> 122 123 /* ifname: interface name from ifconfig structure */ 124 /* eap: Ether address (output) */ 125 int 126 getether(char *ifname, char *eap) 127 { 128 int fd, rc = -1; 129 int n; 130 struct ifreq ibuf[16]; 131 struct ifconf ifc; 132 struct ifreq *ifrp, *ifend; 133 134 /* Fetch the interface configuration */ 135 fd = socket(AF_INET, SOCK_DGRAM, 0); 136 if (fd < 0) { 137 report(LOG_ERR, "getether: socket %s: %s", ifname, get_errmsg()); 138 return (fd); 139 } 140 ifc.ifc_len = sizeof(ibuf); 141 ifc.ifc_buf = (caddr_t) ibuf; 142 if (ioctl(fd, SIOCGIFCONF, (char *) &ifc) < 0 || 143 ifc.ifc_len < sizeof(struct ifreq)) { 144 report(LOG_ERR, "getether: SIOCGIFCONF: %s", get_errmsg()); 145 goto out; 146 } 147 /* Search interface configuration list for link layer address. */ 148 ifrp = ibuf; 149 ifend = (struct ifreq *) ((char *) ibuf + ifc.ifc_len); 150 while (ifrp < ifend) { 151 /* Look for interface */ 152 if (strcmp(ifname, ifrp->ifr_name) == 0 && 153 ifrp->ifr_addr.sa_family == AF_LINK && 154 ((struct sockaddr_dl *) &ifrp->ifr_addr)->sdl_type == IFT_ETHER) { 155 bcopy(LLADDR((struct sockaddr_dl *) &ifrp->ifr_addr), eap, EALEN); 156 rc = 0; 157 break; 158 } 159 /* Bump interface config pointer */ 160 n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); 161 if (n < sizeof(*ifrp)) 162 n = sizeof(*ifrp); 163 ifrp = (struct ifreq *) ((char *) ifrp + n); 164 } 165 166 out: 167 close(fd); 168 return (rc); 169 } 170 171 #define GETETHER 172 #endif /* __NetBSD__ */ 173 174 175 #ifdef SVR4 176 /* 177 * This is for "Streams TCP/IP" by Lachman Associates. 178 * They sure made this cumbersome! -gwr 179 */ 180 181 #include <sys/sockio.h> 182 #include <sys/dlpi.h> 183 #include <stropts.h> 184 #ifndef NULL 185 #define NULL 0 186 #endif 187 188 /* ifname: interface name from ifconfig structure */ 189 /* eap: Ether address (output) */ 190 getether(char *ifname, char *eap) 191 { 192 int rc = -1; 193 char devname[32]; 194 char tmpbuf[sizeof(union DL_primitives) + 16]; 195 struct strbuf cbuf; 196 int fd, flags; 197 union DL_primitives *dlp; 198 char *enaddr; 199 int unit = -1; /* which unit to attach */ 200 201 snprintf(devname, sizeof(devname), "/dev/%s", ifname); 202 fd = open(devname, 2); 203 if (fd < 0) { 204 /* Try without the trailing digit. */ 205 char *p = devname + 5; 206 while (isalpha(*p)) 207 p++; 208 if (isdigit(*p)) { 209 unit = *p - '0'; 210 *p = '\0'; 211 } 212 fd = open(devname, 2); 213 if (fd < 0) { 214 report(LOG_ERR, "getether: open %s: %s", 215 devname, get_errmsg()); 216 return rc; 217 } 218 } 219 #ifdef DL_ATTACH_REQ 220 /* 221 * If this is a "Style 2" DLPI, then we must "attach" first 222 * to tell the driver which unit (board, port) we want. 223 * For now, decide this based on the device name. 224 * (Should do "info_req" and check dl_provider_style ...) 225 */ 226 if (unit >= 0) { 227 memset(tmpbuf, 0, sizeof(tmpbuf)); 228 dlp = (union DL_primitives *) tmpbuf; 229 dlp->dl_primitive = DL_ATTACH_REQ; 230 dlp->attach_req.dl_ppa = unit; 231 cbuf.buf = tmpbuf; 232 cbuf.len = DL_ATTACH_REQ_SIZE; 233 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 234 report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg()); 235 goto out; 236 } 237 /* Recv the ack. */ 238 cbuf.buf = tmpbuf; 239 cbuf.maxlen = sizeof(tmpbuf); 240 flags = 0; 241 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 242 report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg()); 243 goto out; 244 } 245 /* 246 * Check the type, etc. 247 */ 248 if (dlp->dl_primitive == DL_ERROR_ACK) { 249 report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d", 250 dlp->error_ack.dl_errno, 251 dlp->error_ack.dl_unix_errno); 252 goto out; 253 } 254 if (dlp->dl_primitive != DL_OK_ACK) { 255 report(LOG_ERR, "getether: attach: not OK or ERROR"); 256 goto out; 257 } 258 } /* unit >= 0 */ 259 #endif /* DL_ATTACH_REQ */ 260 261 /* 262 * Get the Ethernet address the same way the ARP module 263 * does when it is pushed onto a new stream (bind). 264 * One should instead be able just do an dl_info_req 265 * but many drivers do not supply the hardware address 266 * in the response to dl_info_req (they MUST supply it 267 * for dl_bind_ack because the ARP module requires it). 268 */ 269 memset(tmpbuf, 0, sizeof(tmpbuf)); 270 dlp = (union DL_primitives *) tmpbuf; 271 dlp->dl_primitive = DL_BIND_REQ; 272 dlp->bind_req.dl_sap = 0x8FF; /* XXX - Unused SAP */ 273 cbuf.buf = tmpbuf; 274 cbuf.len = DL_BIND_REQ_SIZE; 275 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 276 report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg()); 277 goto out; 278 } 279 /* Recv the ack. */ 280 cbuf.buf = tmpbuf; 281 cbuf.maxlen = sizeof(tmpbuf); 282 flags = 0; 283 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 284 report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg()); 285 goto out; 286 } 287 /* 288 * Check the type, etc. 289 */ 290 if (dlp->dl_primitive == DL_ERROR_ACK) { 291 report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d", 292 dlp->error_ack.dl_errno, 293 dlp->error_ack.dl_unix_errno); 294 goto out; 295 } 296 if (dlp->dl_primitive != DL_BIND_ACK) { 297 report(LOG_ERR, "getether: bind: not OK or ERROR"); 298 goto out; 299 } 300 if (dlp->bind_ack.dl_addr_offset == 0) { 301 report(LOG_ERR, "getether: bind: ack has no address"); 302 goto out; 303 } 304 if (dlp->bind_ack.dl_addr_length < EALEN) { 305 report(LOG_ERR, "getether: bind: ack address truncated"); 306 goto out; 307 } 308 /* 309 * Copy the Ethernet address out of the message. 310 */ 311 enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset; 312 memcpy(eap, enaddr, EALEN); 313 rc = 0; 314 315 out: 316 close(fd); 317 return rc; 318 } 319 320 #define GETETHER 321 #endif /* SVR4 */ 322 323 324 #ifdef linux 325 /* 326 * This is really easy on Linux! This version (for linux) 327 * written by Nigel Metheringham <nigelm@ohm.york.ac.uk> 328 * 329 * The code is almost identical to the Ultrix code - however 330 * the names are different to confuse the innocent :-) 331 * Most of this code was stolen from the Ultrix bit above. 332 */ 333 334 #include <sys/ioctl.h> 335 #include <net/if.h> /* struct ifreq */ 336 337 /* In a properly configured system this should be either sys/socketio.h 338 or sys/sockios.h, but on my distribution these don't line up correctly */ 339 #include <linux/sockios.h> /* Needed for IOCTL defs */ 340 341 getether(char *ifname, char *eap) 342 { 343 int rc = -1; 344 int fd; 345 struct ifreq phys; 346 347 bzero(&phys, sizeof(phys)); 348 strncpy(phys.ifr_name, ifname, sizeof(phys.ifr_name)); 349 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 350 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 351 return -1; 352 } 353 if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) { 354 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed"); 355 } else { 356 bcopy(phys.ifr_hwaddr, eap, EALEN); 357 rc = 0; 358 } 359 close(fd); 360 return rc; 361 } 362 363 #define GETETHER 364 #endif /* linux */ 365 366 367 /* If we don't know how on this system, just return an error. */ 368 #ifndef GETETHER 369 getether(char *ifname, char *eap) 370 { 371 return -1; 372 } 373 374 #endif /* !GETETHER */ 375 376 /* 377 * Local Variables: 378 * tab-width: 4 379 * c-indent-level: 4 380 * c-argdecl-indent: 4 381 * c-continued-statement-offset: 4 382 * c-continued-brace-offset: -4 383 * c-label-offset: -4 384 * c-brace-offset: 0 385 * End: 386 */ 387