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 /*
 123  * ifname - interface name from ifconfig structure
 124  * eap    - Ether address (output)
 125  */
 126 int
 127 getether(char *ifname, char *eap)
 128 {
 129         int fd, rc = -1;
 130         int n;
 131         struct ifreq ibuf[16];
 132         struct ifconf ifc;
 133         struct ifreq *ifrp, *ifend;
 134
 135         /* Fetch the interface configuration */
 136         fd = socket(AF_INET, SOCK_DGRAM, 0);
 137         if (fd < 0) {
 138                 report(LOG_ERR, "getether: socket %s: %s", ifname, get_errmsg());
 139                 return (fd);
 140         }
 141         ifc.ifc_len = sizeof(ibuf);
 142         ifc.ifc_buf = (caddr_t) ibuf;
 143         if (ioctl(fd, SIOCGIFCONF, (char *) &ifc) < 0 ||
 144                 ifc.ifc_len < sizeof(struct ifreq)) {
 145                 report(LOG_ERR, "getether: SIOCGIFCONF: %s", get_errmsg());
 146                 goto out;
 147         }
 148         /* Search interface configuration list for link layer address. */
 149         ifrp = ibuf;
 150         ifend = (struct ifreq *) ((char *) ibuf + ifc.ifc_len);
 151         while (ifrp < ifend) {
 152                 /* Look for interface */
 153                 if (strcmp(ifname, ifrp->ifr_name) == 0 &&
 154                         ifrp->ifr_addr.sa_family == AF_LINK &&
 155                 ((struct sockaddr_dl *) &ifrp->ifr_addr)->sdl_type == IFT_ETHER) {
 156                         bcopy(LLADDR((struct sockaddr_dl *) &ifrp->ifr_addr), eap, EALEN);
 157                         rc = 0;
 158                         break;
 159                 }
 160                 /* Bump interface config pointer */
 161                 n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
 162                 if (n < sizeof(*ifrp))
 163                         n = sizeof(*ifrp);
 164                 ifrp = (struct ifreq *) ((char *) ifrp + n);
 165         }
 166
 167   out:
 168         close(fd);
 169         return (rc);
 170 }
 171
 172 #define GETETHER
 173 #endif /* __NetBSD__ */
 174 \f
 175
 176 #ifdef  SVR4
 177 /*
 178  * This is for "Streams TCP/IP" by Lachman Associates.
 179  * They sure made this cumbersome!  -gwr
 180  */
 181
 182 #include <sys/sockio.h>
 183 #include <sys/dlpi.h>
 184 #include <stropts.h>
 185 #include <string.h>
 186
 187 int
 188 getether(ifname, eap)
 189         char *ifname;                           /* interface name from ifconfig structure */
 190         char *eap;                                      /* Ether address (output) */
 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), "%s%s", _PATH_DEV, 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 \f
 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> and
 328  * updated by Pauline Middelink <middelin@polyware.iaf.nl>
 329  *
 330  * The code is almost identical to the Ultrix code - however
 331  * the names are different to confuse the innocent :-)
 332  * Most of this code was stolen from the Ultrix bit above.
 333  */
 334
 335 #include <memory.h>
 336 #include <sys/ioctl.h>
 337 #include <net/if.h>             /* struct ifreq */
 338 #include <sys/socketio.h>       /* Needed for IOCTL defs */
 339
 340 int
 341 getether(ifname, eap)
 342         char *ifname, *eap;
 343 {
 344         int rc = -1;
 345         int fd;
 346         struct ifreq phys;
 347
 348         memset(&phys, 0, sizeof(phys));
 349         strcpy(phys.ifr_name, ifname);
 350         if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
 351                 report(LOG_ERR, "getether: socket(INET,DGRAM) failed");
 352                 return -1;
 353         }
 354         if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) {
 355                 report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed");
 356         } else {
 357                 memcpy(eap, &phys.ifr_hwaddr.sa_data, EALEN);
 358                 rc = 0;
 359         }
 360         close(fd);
 361         return rc;
 362 }
 363
 364 #define GETETHER
 365 #endif  /* __linux__ */
 366
 367
 368 /* If we don't know how on this system, just return an error. */
 369 #ifndef GETETHER
 370 int
 371 getether(ifname, eap)
 372         char *ifname, *eap;
 373 {
 374         return -1;
 375 }
 376
 377 #endif /* !GETETHER */
 378
 379 /*
 380  * Local Variables:
 381  * tab-width: 4
 382  * c-indent-level: 4
 383  * c-argdecl-indent: 4
 384  * c-continued-statement-offset: 4
 385  * c-continued-brace-offset: -4
 386  * c-label-offset: -4
 387  * c-brace-offset: 0
 388  * End:
 389  */