1 /* 2 * getether.c : get the ethernet address of an interface 3 * 4 * All of this code is quite system-specific. As you may well 5 * guess, it took a good bit of detective work to figure out! 6 * 7 * If you figure out how to do this on another system, 8 * please let me know. <gwr@mc.com> 9 * 10 * $FreeBSD: src/libexec/bootpd/getether.c,v 1.9.2.3 2003/02/15 05:36:01 kris Exp $ 11 * $DragonFly: src/libexec/bootpd/getether.c,v 1.3 2004/02/13 03:49:47 dillon Exp $ 12 */ 13 14 #include <sys/types.h> 15 #include <sys/socket.h> 16 17 #ifndef NO_UNISTD 18 #include <unistd.h> 19 #endif 20 21 #include <ctype.h> 22 #include <paths.h> 23 #include <string.h> 24 #include <syslog.h> 25 26 #include "getether.h" 27 #include "report.h" 28 #define EALEN 6 29 30 #if defined(ultrix) || (defined(__osf__) && defined(__alpha)) 31 /* 32 * This is really easy on Ultrix! Thanks to 33 * Harald Lundberg <hl@tekla.fi> for this code. 34 * 35 * The code here is not specific to the Alpha, but that was the 36 * only symbol we could find to identify DEC's version of OSF. 37 * (Perhaps we should just define DEC in the Makefile... -gwr) 38 */ 39 40 #include <sys/ioctl.h> 41 #include <net/if.h> /* struct ifdevea */ 42 43 getether(ifname, eap) 44 char *ifname, *eap; 45 { 46 int rc = -1; 47 int fd; 48 struct ifdevea phys; 49 bzero(&phys, sizeof(phys)); 50 strcpy(phys.ifr_name, ifname); 51 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 52 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 53 return -1; 54 } 55 if (ioctl(fd, SIOCRPHYSADDR, &phys) < 0) { 56 report(LOG_ERR, "getether: ioctl SIOCRPHYSADDR failed"); 57 } else { 58 bcopy(&phys.current_pa[0], eap, EALEN); 59 rc = 0; 60 } 61 close(fd); 62 return rc; 63 } 64 65 #define GETETHER 66 #endif /* ultrix|osf1 */ 67 68 69 #ifdef SUNOS 70 71 #include <sys/sockio.h> 72 #include <sys/time.h> /* needed by net_if.h */ 73 #include <net/nit_if.h> /* for NIOCBIND */ 74 #include <net/if.h> /* for struct ifreq */ 75 76 getether(ifname, eap) 77 char *ifname; /* interface name from ifconfig structure */ 78 char *eap; /* Ether address (output) */ 79 { 80 int rc = -1; 81 82 struct ifreq ifrnit; 83 int nit; 84 85 bzero((char *) &ifrnit, sizeof(ifrnit)); 86 strncpy(&ifrnit.ifr_name[0], ifname, IFNAMSIZ); 87 88 nit = open("/dev/nit", 0); 89 if (nit < 0) { 90 report(LOG_ERR, "getether: open /dev/nit: %s", 91 get_errmsg()); 92 return rc; 93 } 94 do { 95 if (ioctl(nit, NIOCBIND, &ifrnit) < 0) { 96 report(LOG_ERR, "getether: NIOCBIND on nit"); 97 break; 98 } 99 if (ioctl(nit, SIOCGIFADDR, &ifrnit) < 0) { 100 report(LOG_ERR, "getether: SIOCGIFADDR on nit"); 101 break; 102 } 103 bcopy(&ifrnit.ifr_addr.sa_data[0], eap, EALEN); 104 rc = 0; 105 } while (0); 106 close(nit); 107 return rc; 108 } 109 110 #define GETETHER 111 #endif /* SUNOS */ 112 113 114 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) 115 /* Thanks to John Brezak <brezak@ch.hp.com> for this code. */ 116 #include <sys/ioctl.h> 117 #include <sys/time.h> 118 #include <net/if.h> 119 #include <net/if_dl.h> 120 #include <net/if_types.h> 121 122 int 123 getether(ifname, eap) 124 char *ifname; /* interface name from ifconfig structure */ 125 char *eap; /* Ether address (output) */ 126 { 127 int fd, rc = -1; 128 register int n; 129 struct ifreq ibuf[16]; 130 struct ifconf ifc; 131 register 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 #include <string.h> 184 #ifndef NULL 185 #define NULL 0 186 #endif 187 188 int 189 getether(ifname, eap) 190 char *ifname; /* interface name from ifconfig structure */ 191 char *eap; /* Ether address (output) */ 192 { 193 int rc = -1; 194 char devname[32]; 195 char tmpbuf[sizeof(union DL_primitives) + 16]; 196 struct strbuf cbuf; 197 int fd, flags; 198 union DL_primitives *dlp; 199 char *enaddr; 200 int unit = -1; /* which unit to attach */ 201 202 snprintf(devname, sizeof(devname), "%s%s", _PATH_DEV, ifname); 203 fd = open(devname, 2); 204 if (fd < 0) { 205 /* Try without the trailing digit. */ 206 char *p = devname + 5; 207 while (isalpha(*p)) 208 p++; 209 if (isdigit(*p)) { 210 unit = *p - '0'; 211 *p = '\0'; 212 } 213 fd = open(devname, 2); 214 if (fd < 0) { 215 report(LOG_ERR, "getether: open %s: %s", 216 devname, get_errmsg()); 217 return rc; 218 } 219 } 220 #ifdef DL_ATTACH_REQ 221 /* 222 * If this is a "Style 2" DLPI, then we must "attach" first 223 * to tell the driver which unit (board, port) we want. 224 * For now, decide this based on the device name. 225 * (Should do "info_req" and check dl_provider_style ...) 226 */ 227 if (unit >= 0) { 228 memset(tmpbuf, 0, sizeof(tmpbuf)); 229 dlp = (union DL_primitives *) tmpbuf; 230 dlp->dl_primitive = DL_ATTACH_REQ; 231 dlp->attach_req.dl_ppa = unit; 232 cbuf.buf = tmpbuf; 233 cbuf.len = DL_ATTACH_REQ_SIZE; 234 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 235 report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg()); 236 goto out; 237 } 238 /* Recv the ack. */ 239 cbuf.buf = tmpbuf; 240 cbuf.maxlen = sizeof(tmpbuf); 241 flags = 0; 242 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 243 report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg()); 244 goto out; 245 } 246 /* 247 * Check the type, etc. 248 */ 249 if (dlp->dl_primitive == DL_ERROR_ACK) { 250 report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d", 251 dlp->error_ack.dl_errno, 252 dlp->error_ack.dl_unix_errno); 253 goto out; 254 } 255 if (dlp->dl_primitive != DL_OK_ACK) { 256 report(LOG_ERR, "getether: attach: not OK or ERROR"); 257 goto out; 258 } 259 } /* unit >= 0 */ 260 #endif /* DL_ATTACH_REQ */ 261 262 /* 263 * Get the Ethernet address the same way the ARP module 264 * does when it is pushed onto a new stream (bind). 265 * One should instead be able just do an dl_info_req 266 * but many drivers do not supply the hardware address 267 * in the response to dl_info_req (they MUST supply it 268 * for dl_bind_ack because the ARP module requires it). 269 */ 270 memset(tmpbuf, 0, sizeof(tmpbuf)); 271 dlp = (union DL_primitives *) tmpbuf; 272 dlp->dl_primitive = DL_BIND_REQ; 273 dlp->bind_req.dl_sap = 0x8FF; /* XXX - Unused SAP */ 274 cbuf.buf = tmpbuf; 275 cbuf.len = DL_BIND_REQ_SIZE; 276 if (putmsg(fd, &cbuf, NULL, 0) < 0) { 277 report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg()); 278 goto out; 279 } 280 /* Recv the ack. */ 281 cbuf.buf = tmpbuf; 282 cbuf.maxlen = sizeof(tmpbuf); 283 flags = 0; 284 if (getmsg(fd, &cbuf, NULL, &flags) < 0) { 285 report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg()); 286 goto out; 287 } 288 /* 289 * Check the type, etc. 290 */ 291 if (dlp->dl_primitive == DL_ERROR_ACK) { 292 report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d", 293 dlp->error_ack.dl_errno, 294 dlp->error_ack.dl_unix_errno); 295 goto out; 296 } 297 if (dlp->dl_primitive != DL_BIND_ACK) { 298 report(LOG_ERR, "getether: bind: not OK or ERROR"); 299 goto out; 300 } 301 if (dlp->bind_ack.dl_addr_offset == 0) { 302 report(LOG_ERR, "getether: bind: ack has no address"); 303 goto out; 304 } 305 if (dlp->bind_ack.dl_addr_length < EALEN) { 306 report(LOG_ERR, "getether: bind: ack address truncated"); 307 goto out; 308 } 309 /* 310 * Copy the Ethernet address out of the message. 311 */ 312 enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset; 313 memcpy(eap, enaddr, EALEN); 314 rc = 0; 315 316 out: 317 close(fd); 318 return rc; 319 } 320 321 #define GETETHER 322 #endif /* SVR4 */ 323 324 325 #ifdef __linux__ 326 /* 327 * This is really easy on Linux! This version (for linux) 328 * written by Nigel Metheringham <nigelm@ohm.york.ac.uk> and 329 * updated by Pauline Middelink <middelin@polyware.iaf.nl> 330 * 331 * The code is almost identical to the Ultrix code - however 332 * the names are different to confuse the innocent :-) 333 * Most of this code was stolen from the Ultrix bit above. 334 */ 335 336 #include <memory.h> 337 #include <sys/ioctl.h> 338 #include <net/if.h> /* struct ifreq */ 339 #include <sys/socketio.h> /* Needed for IOCTL defs */ 340 341 int 342 getether(ifname, eap) 343 char *ifname, *eap; 344 { 345 int rc = -1; 346 int fd; 347 struct ifreq phys; 348 349 memset(&phys, 0, sizeof(phys)); 350 strcpy(phys.ifr_name, ifname); 351 if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 352 report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); 353 return -1; 354 } 355 if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) { 356 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed"); 357 } else { 358 memcpy(eap, &phys.ifr_hwaddr.sa_data, EALEN); 359 rc = 0; 360 } 361 close(fd); 362 return rc; 363 } 364 365 #define GETETHER 366 #endif /* __linux__ */ 367 368 369 /* If we don't know how on this system, just return an error. */ 370 #ifndef GETETHER 371 int 372 getether(ifname, eap) 373 char *ifname, *eap; 374 { 375 return -1; 376 } 377 378 #endif /* !GETETHER */ 379 380 /* 381 * Local Variables: 382 * tab-width: 4 383 * c-indent-level: 4 384 * c-argdecl-indent: 4 385 * c-continued-statement-offset: 4 386 * c-continued-brace-offset: -4 387 * c-label-offset: -4 388 * c-brace-offset: 0 389 * End: 390 */ 391