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