/* * getether.c : get the ethernet address of an interface * * All of this code is quite system-specific. As you may well * guess, it took a good bit of detective work to figure out! * * If you figure out how to do this on another system, * please let me know. * * $FreeBSD: src/libexec/bootpd/getether.c,v 1.9.2.3 2003/02/15 05:36:01 kris Exp $ */ #include #include #ifndef NO_UNISTD #include #endif #include #include #include #include #include "getether.h" #include "report.h" #define EALEN 6 #if defined(ultrix) || (defined(__osf__) && defined(__alpha)) /* * This is really easy on Ultrix! Thanks to * Harald Lundberg for this code. * * The code here is not specific to the Alpha, but that was the * only symbol we could find to identify DEC's version of OSF. * (Perhaps we should just define DEC in the Makefile... -gwr) */ #include #include /* struct ifdevea */ getether(ifname, eap) char *ifname, *eap; { int rc = -1; int fd; struct ifdevea phys; bzero(&phys, sizeof(phys)); strcpy(phys.ifr_name, ifname); if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); return -1; } if (ioctl(fd, SIOCRPHYSADDR, &phys) < 0) { report(LOG_ERR, "getether: ioctl SIOCRPHYSADDR failed"); } else { bcopy(&phys.current_pa[0], eap, EALEN); rc = 0; } close(fd); return rc; } #define GETETHER #endif /* ultrix|osf1 */ #ifdef SUNOS #include #include /* needed by net_if.h */ #include /* for NIOCBIND */ #include /* for struct ifreq */ getether(ifname, eap) char *ifname; /* interface name from ifconfig structure */ char *eap; /* Ether address (output) */ { int rc = -1; struct ifreq ifrnit; int nit; bzero((char *) &ifrnit, sizeof(ifrnit)); strncpy(&ifrnit.ifr_name[0], ifname, IFNAMSIZ); nit = open("/dev/nit", 0); if (nit < 0) { report(LOG_ERR, "getether: open /dev/nit: %s", get_errmsg()); return rc; } do { if (ioctl(nit, NIOCBIND, &ifrnit) < 0) { report(LOG_ERR, "getether: NIOCBIND on nit"); break; } if (ioctl(nit, SIOCGIFADDR, &ifrnit) < 0) { report(LOG_ERR, "getether: SIOCGIFADDR on nit"); break; } bcopy(&ifrnit.ifr_addr.sa_data[0], eap, EALEN); rc = 0; } while (0); close(nit); return rc; } #define GETETHER #endif /* SUNOS */ #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) /* Thanks to John Brezak for this code. */ #include #include #include #include #include /* * ifname - interface name from ifconfig structure * eap - Ether address (output) */ int getether(char *ifname, char *eap) { int fd, rc = -1; int n; struct ifreq ibuf[16]; struct ifconf ifc; struct ifreq *ifrp, *ifend; /* Fetch the interface configuration */ fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd < 0) { report(LOG_ERR, "getether: socket %s: %s", ifname, get_errmsg()); return (fd); } ifc.ifc_len = sizeof(ibuf); ifc.ifc_buf = (caddr_t) ibuf; if (ioctl(fd, SIOCGIFCONF, (char *) &ifc) < 0 || ifc.ifc_len < sizeof(struct ifreq)) { report(LOG_ERR, "getether: SIOCGIFCONF: %s", get_errmsg()); goto out; } /* Search interface configuration list for link layer address. */ ifrp = ibuf; ifend = (struct ifreq *) ((char *) ibuf + ifc.ifc_len); while (ifrp < ifend) { /* Look for interface */ if (strcmp(ifname, ifrp->ifr_name) == 0 && ifrp->ifr_addr.sa_family == AF_LINK && ((struct sockaddr_dl *) &ifrp->ifr_addr)->sdl_type == IFT_ETHER) { bcopy(LLADDR((struct sockaddr_dl *) &ifrp->ifr_addr), eap, EALEN); rc = 0; break; } /* Bump interface config pointer */ n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); if (n < sizeof(*ifrp)) n = sizeof(*ifrp); ifrp = (struct ifreq *) ((char *) ifrp + n); } out: close(fd); return (rc); } #define GETETHER #endif /* __NetBSD__ */ #ifdef SVR4 /* * This is for "Streams TCP/IP" by Lachman Associates. * They sure made this cumbersome! -gwr */ #include #include #include #include int getether(ifname, eap) char *ifname; /* interface name from ifconfig structure */ char *eap; /* Ether address (output) */ { int rc = -1; char devname[32]; char tmpbuf[sizeof(union DL_primitives) + 16]; struct strbuf cbuf; int fd, flags; union DL_primitives *dlp; char *enaddr; int unit = -1; /* which unit to attach */ snprintf(devname, sizeof(devname), "%s%s", _PATH_DEV, ifname); fd = open(devname, 2); if (fd < 0) { /* Try without the trailing digit. */ char *p = devname + 5; while (isalpha(*p)) p++; if (isdigit(*p)) { unit = *p - '0'; *p = '\0'; } fd = open(devname, 2); if (fd < 0) { report(LOG_ERR, "getether: open %s: %s", devname, get_errmsg()); return rc; } } #ifdef DL_ATTACH_REQ /* * If this is a "Style 2" DLPI, then we must "attach" first * to tell the driver which unit (board, port) we want. * For now, decide this based on the device name. * (Should do "info_req" and check dl_provider_style ...) */ if (unit >= 0) { memset(tmpbuf, 0, sizeof(tmpbuf)); dlp = (union DL_primitives *) tmpbuf; dlp->dl_primitive = DL_ATTACH_REQ; dlp->attach_req.dl_ppa = unit; cbuf.buf = tmpbuf; cbuf.len = DL_ATTACH_REQ_SIZE; if (putmsg(fd, &cbuf, NULL, 0) < 0) { report(LOG_ERR, "getether: attach: putmsg: %s", get_errmsg()); goto out; } /* Recv the ack. */ cbuf.buf = tmpbuf; cbuf.maxlen = sizeof(tmpbuf); flags = 0; if (getmsg(fd, &cbuf, NULL, &flags) < 0) { report(LOG_ERR, "getether: attach: getmsg: %s", get_errmsg()); goto out; } /* * Check the type, etc. */ if (dlp->dl_primitive == DL_ERROR_ACK) { report(LOG_ERR, "getether: attach: dlpi_errno=%d, unix_errno=%d", dlp->error_ack.dl_errno, dlp->error_ack.dl_unix_errno); goto out; } if (dlp->dl_primitive != DL_OK_ACK) { report(LOG_ERR, "getether: attach: not OK or ERROR"); goto out; } } /* unit >= 0 */ #endif /* DL_ATTACH_REQ */ /* * Get the Ethernet address the same way the ARP module * does when it is pushed onto a new stream (bind). * One should instead be able just do an dl_info_req * but many drivers do not supply the hardware address * in the response to dl_info_req (they MUST supply it * for dl_bind_ack because the ARP module requires it). */ memset(tmpbuf, 0, sizeof(tmpbuf)); dlp = (union DL_primitives *) tmpbuf; dlp->dl_primitive = DL_BIND_REQ; dlp->bind_req.dl_sap = 0x8FF; /* XXX - Unused SAP */ cbuf.buf = tmpbuf; cbuf.len = DL_BIND_REQ_SIZE; if (putmsg(fd, &cbuf, NULL, 0) < 0) { report(LOG_ERR, "getether: bind: putmsg: %s", get_errmsg()); goto out; } /* Recv the ack. */ cbuf.buf = tmpbuf; cbuf.maxlen = sizeof(tmpbuf); flags = 0; if (getmsg(fd, &cbuf, NULL, &flags) < 0) { report(LOG_ERR, "getether: bind: getmsg: %s", get_errmsg()); goto out; } /* * Check the type, etc. */ if (dlp->dl_primitive == DL_ERROR_ACK) { report(LOG_ERR, "getether: bind: dlpi_errno=%d, unix_errno=%d", dlp->error_ack.dl_errno, dlp->error_ack.dl_unix_errno); goto out; } if (dlp->dl_primitive != DL_BIND_ACK) { report(LOG_ERR, "getether: bind: not OK or ERROR"); goto out; } if (dlp->bind_ack.dl_addr_offset == 0) { report(LOG_ERR, "getether: bind: ack has no address"); goto out; } if (dlp->bind_ack.dl_addr_length < EALEN) { report(LOG_ERR, "getether: bind: ack address truncated"); goto out; } /* * Copy the Ethernet address out of the message. */ enaddr = tmpbuf + dlp->bind_ack.dl_addr_offset; memcpy(eap, enaddr, EALEN); rc = 0; out: close(fd); return rc; } #define GETETHER #endif /* SVR4 */ #ifdef __linux__ /* * This is really easy on Linux! This version (for linux) * written by Nigel Metheringham and * updated by Pauline Middelink * * The code is almost identical to the Ultrix code - however * the names are different to confuse the innocent :-) * Most of this code was stolen from the Ultrix bit above. */ #include #include #include /* struct ifreq */ #include /* Needed for IOCTL defs */ int getether(ifname, eap) char *ifname, *eap; { int rc = -1; int fd; struct ifreq phys; memset(&phys, 0, sizeof(phys)); strcpy(phys.ifr_name, ifname); if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { report(LOG_ERR, "getether: socket(INET,DGRAM) failed"); return -1; } if (ioctl(fd, SIOCGIFHWADDR, &phys) < 0) { report(LOG_ERR, "getether: ioctl SIOCGIFHWADDR failed"); } else { memcpy(eap, &phys.ifr_hwaddr.sa_data, EALEN); rc = 0; } close(fd); return rc; } #define GETETHER #endif /* __linux__ */ /* If we don't know how on this system, just return an error. */ #ifndef GETETHER int getether(ifname, eap) char *ifname, *eap; { return -1; } #endif /* !GETETHER */