libexec/bootpd/getether.c

   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 1.4 2008/06/05 18:01:49 swildner 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 \f
  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 \f
 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 \f
 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
 185 int
 186 getether(ifname, eap)
 187         char *ifname;                           /* interface name from ifconfig structure */
 188         char *eap;                                      /* Ether address (output) */
 189 {
 190         int rc = -1;
 191         char devname[32];
 192         char tmpbuf[sizeof(union DL_primitives) + 16];
 193         struct strbuf cbuf;
 194         int fd, flags;
 195         union DL_primitives *dlp;
 196         char *enaddr;
 197         int unit = -1;                          /* which unit to attach */
 198
 199         snprintf(devname, sizeof(devname), "%s%s", _PATH_DEV, ifname);
 200         fd = open(devname, 2);
 201         if (fd < 0) {
 202                 /* Try without the trailing digit. */
 203                 char *p = devname + 5;
 204                 while (isalpha(*p))
 205                         p++;
 206                 if (isdigit(*p)) {
 207                         unit = *p - '0';
 208                         *p = '\0';
 209                 }
 210                 fd = open(devname, 2);
 211                 if (fd < 0) {
 212                         report(LOG_ERR, "getether: open %s: %s",
 213                                    devname, get_errmsg());
 214                         return rc;
 215                 }
 216         }
 217 #ifdef  DL_ATTACH_REQ
 218         /*
 219          * If this is a "Style 2" DLPI, then we must "attach" first
 220          * to tell the driver which unit (board, port) we want.
 221          * For now, decide this based on the device name.
 222          * (Should do "info_req" and check dl_provider_style ...)
 223          */
 224         if (unit >= 0) {
 225                 memset(tmpbuf, 0, sizeof(tmpbuf));
 226                 dlp = (union DL_primitives *) tmpbuf;
 227                 dlp->dl_primitive = DL_ATTACH_REQ;
 228                 dlp->attach_req.dl_ppa = unit;
 229                 cbuf.buf = tmpbuf;
 230                 cbuf.len = DL_ATTACH_REQ_SIZE;
 231                 if (putmsg(fd, &cbuf, NULL, 0) < 0) {
 232                         report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg());
 233                         goto out;
 234                 }
 235                 /* Recv the ack. */
 236                 cbuf.buf = tmpbuf;
 237                 cbuf.maxlen = sizeof(tmpbuf);
 238                 flags = 0;
 239                 if (getmsg(fd, &cbuf, NULL, &flags) < 0) {
 240                         report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg());
 241                         goto out;
 242                 }
 243                 /*
 244                  * Check the type, etc.
 245                  */
 246                 if (dlp->dl_primitive == DL_ERROR_ACK) {
 247                         report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d",
 248                                    dlp->error_ack.dl_errno,
 249                                    dlp->error_ack.dl_unix_errno);
 250                         goto out;
 251                 }
 252                 if (dlp->dl_primitive != DL_OK_ACK) {
 253                         report(LOG_ERR, "getether: attach: not OK or ERROR");
 254                         goto out;
 255                 }
 256         } /* unit >= 0 */
 257 #endif  /* DL_ATTACH_REQ */
 258
 259         /*
 260          * Get the Ethernet address the same way the ARP module
 261          * does when it is pushed onto a new stream (bind).
 262          * One should instead be able just do an dl_info_req
 263          * but many drivers do not supply the hardware address
 264          * in the response to dl_info_req (they MUST supply it
 265          * for dl_bind_ack because the ARP module requires it).
 266          */
 267         memset(tmpbuf, 0, sizeof(tmpbuf));
 268         dlp = (union DL_primitives *) tmpbuf;
 269         dlp->dl_primitive = DL_BIND_REQ;
 270         dlp->bind_req.dl_sap = 0x8FF;   /* XXX - Unused SAP */
 271         cbuf.buf = tmpbuf;
 272         cbuf.len = DL_BIND_REQ_SIZE;
 273         if (putmsg(fd, &cbuf, NULL, 0) < 0) {
 274                 report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg());
 275                 goto out;
 276         }
 277         /* Recv the ack. */
 278         cbuf.buf = tmpbuf;
 279         cbuf.maxlen = sizeof(tmpbuf);
 280         flags = 0;
 281         if (getmsg(fd, &cbuf, NULL, &flags) < 0) {
 282                 report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg());
 283                 goto out;
 284         }
 285         /*
 286          * Check the type, etc.
 287          */
 288         if (dlp->dl_primitive == DL_ERROR_ACK) {
 289                 report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d",
 290                            dlp->error_ack.dl_errno,
 291                            dlp->error_ack.dl_unix_errno);
 292                 goto out;
 293         }
 294         if (dlp->dl_primitive != DL_BIND_ACK) {
 295                 report(LOG_ERR, "getether: bind: not OK or ERROR");
 296                 goto out;
 297         }
 298         if (dlp->bind_ack.dl_addr_offset == 0) {
 299                 report(LOG_ERR, "getether: bind: ack has no address");
 300                 goto out;
 301         }
 302         if (dlp->bind_ack.dl_addr_length < EALEN) {
 303                 report(LOG_ERR, "getether: bind: ack address truncated");
 304                 goto out;
 305         }
 306         /*
 307          * Copy the Ethernet address out of the message.
 308          */
 309         enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset;
 310         memcpy(eap, enaddr, EALEN);
 311         rc = 0;
 312
 313   out:
 314         close(fd);
 315         return rc;
 316 }
 317
 318 #define GETETHER
 319 #endif /* SVR4 */
 320 \f
 321
 322 #ifdef  __linux__
 323 /*
 324  * This is really easy on Linux!  This version (for linux)
 325  * written by Nigel Metheringham <nigelm@ohm.york.ac.uk> and
 326  * updated by Pauline Middelink <middelin@polyware.iaf.nl>
 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 <memory.h>
 334 #include <sys/ioctl.h>
 335 #include <net/if.h>             /* struct ifreq */
 336 #include <sys/socketio.h>       /* Needed for IOCTL defs */
 337
 338 int
 339 getether(ifname, eap)
 340         char *ifname, *eap;
 341 {
 342         int rc = -1;
 343         int fd;
 344         struct ifreq phys;
 345
 346         memset(&phys, 0, sizeof(phys));
 347         strcpy(phys.ifr_name, ifname);
 348         if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
 349                 report(LOG_ERR, "getether: socket(INET,DGRAM) failed");
 350                 return -1;
 351         }
 352         if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) {
 353                 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed");
 354         } else {
 355                 memcpy(eap, &phys.ifr_hwaddr.sa_data, EALEN);
 356                 rc = 0;
 357         }
 358         close(fd);
 359         return rc;
 360 }
 361
 362 #define GETETHER
 363 #endif  /* __linux__ */
 364
 365
 366 /* If we don't know how on this system, just return an error. */
 367 #ifndef GETETHER
 368 int
 369 getether(ifname, eap)
 370         char *ifname, *eap;
 371 {
 372         return -1;
 373 }
 374
 375 #endif /* !GETETHER */
 376
 377 /*
 378  * Local Variables:
 379  * tab-width: 4
 380  * c-indent-level: 4
 381  * c-argdecl-indent: 4
 382  * c-continued-statement-offset: 4
 383  * c-continued-brace-offset: -4
 384  * c-label-offset: -4
 385  * c-brace-offset: 0
 386  * End:
 387  */