diff options
Diffstat (limited to 'lib/libstand/rarp.c')
| -rw-r--r-- | lib/libstand/rarp.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/lib/libstand/rarp.c b/lib/libstand/rarp.c new file mode 100644 index 0000000..898e475 --- /dev/null +++ b/lib/libstand/rarp.c @@ -0,0 +1,225 @@ +/* $NetBSD: rarp.c,v 1.16 1997/07/07 15:52:52 drochner Exp $ */ + +/* + * Copyright (c) 1992 Regents of the University of California. + * All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#) Header: arp.c,v 1.5 93/07/15 05:52:26 leres Exp (LBL) + */ +#include <sys/param.h> +#include <sys/socket.h> +#include <net/if.h> +#include <netinet/in.h> +#include <netinet/if_ether.h> + +#include <netinet/in_systm.h> + +#include <string.h> + +#include "stand.h" +#include "net.h" +#include "netif.h" + + +static ssize_t rarpsend(struct iodesc *, void *, size_t); +static ssize_t rarprecv(struct iodesc *, void *, size_t, time_t); + +/* + * Ethernet (Reverse) Address Resolution Protocol (see RFC 903, and 826). + */ +int +rarp_getipaddress(sock) + int sock; +{ + struct iodesc *d; + register struct ether_arp *ap; + struct { + u_char header[ETHER_SIZE]; + struct { + struct ether_arp arp; + u_char pad[18]; /* 60 - sizeof(arp) */ + } data; + } wbuf; + struct { + u_char header[ETHER_SIZE]; + struct { + struct ether_arp arp; + u_char pad[24]; /* extra space */ + } data; + } rbuf; + +#ifdef RARP_DEBUG + if (debug) + printf("rarp: socket=%d\n", sock); +#endif + if (!(d = socktodesc(sock))) { + printf("rarp: bad socket. %d\n", sock); + return (-1); + } +#ifdef RARP_DEBUG + if (debug) + printf("rarp: d=%x\n", (u_int)d); +#endif + + bzero((char*)&wbuf.data, sizeof(wbuf.data)); + ap = &wbuf.data.arp; + ap->arp_hrd = htons(ARPHRD_ETHER); + ap->arp_pro = htons(ETHERTYPE_IP); + ap->arp_hln = sizeof(ap->arp_sha); /* hardware address length */ + ap->arp_pln = sizeof(ap->arp_spa); /* protocol address length */ + ap->arp_op = htons(ARPOP_REVREQUEST); + bcopy(d->myea, ap->arp_sha, 6); + bcopy(d->myea, ap->arp_tha, 6); + + if (sendrecv(d, + rarpsend, &wbuf.data, sizeof(wbuf.data), + rarprecv, &rbuf.data, sizeof(rbuf.data)) < 0) + { + printf("No response for RARP request\n"); + return (-1); + } + + ap = &rbuf.data.arp; + bcopy(ap->arp_tpa, (char *)&myip, sizeof(myip)); +#if 0 + /* XXX - Can NOT assume this is our root server! */ + bcopy(ap->arp_spa, (char *)&rootip, sizeof(rootip)); +#endif + + /* Compute our "natural" netmask. */ + if (IN_CLASSA(myip.s_addr)) + netmask = IN_CLASSA_NET; + else if (IN_CLASSB(myip.s_addr)) + netmask = IN_CLASSB_NET; + else + netmask = IN_CLASSC_NET; + + d->myip = myip; + return (0); +} + +/* + * Broadcast a RARP request (i.e. who knows who I am) + */ +static ssize_t +rarpsend(d, pkt, len) + register struct iodesc *d; + register void *pkt; + register size_t len; +{ + +#ifdef RARP_DEBUG + if (debug) + printf("rarpsend: called\n"); +#endif + + return (sendether(d, pkt, len, bcea, ETHERTYPE_REVARP)); +} + +/* + * Returns 0 if this is the packet we're waiting for + * else -1 (and errno == 0) + */ +static ssize_t +rarprecv(d, pkt, len, tleft) + register struct iodesc *d; + register void *pkt; + register size_t len; + time_t tleft; +{ + register ssize_t n; + register struct ether_arp *ap; + u_int16_t etype; /* host order */ + +#ifdef RARP_DEBUG + if (debug) + printf("rarprecv: "); +#endif + + n = readether(d, pkt, len, tleft, &etype); + errno = 0; /* XXX */ + if (n == -1 || n < sizeof(struct ether_arp)) { +#ifdef RARP_DEBUG + if (debug) + printf("bad len=%d\n", n); +#endif + return (-1); + } + + if (etype != ETHERTYPE_REVARP) { +#ifdef RARP_DEBUG + if (debug) + printf("bad type=0x%x\n", etype); +#endif + return (-1); + } + + ap = (struct ether_arp *)pkt; + if (ap->arp_hrd != htons(ARPHRD_ETHER) || + ap->arp_pro != htons(ETHERTYPE_IP) || + ap->arp_hln != sizeof(ap->arp_sha) || + ap->arp_pln != sizeof(ap->arp_spa) ) + { +#ifdef RARP_DEBUG + if (debug) + printf("bad hrd/pro/hln/pln\n"); +#endif + return (-1); + } + + if (ap->arp_op != htons(ARPOP_REVREPLY)) { +#ifdef RARP_DEBUG + if (debug) + printf("bad op=0x%x\n", ntohs(ap->arp_op)); +#endif + return (-1); + } + + /* Is the reply for our Ethernet address? */ + if (bcmp(ap->arp_tha, d->myea, 6)) { +#ifdef RARP_DEBUG + if (debug) + printf("unwanted address\n"); +#endif + return (-1); + } + + /* We have our answer. */ +#ifdef RARP_DEBUG + if (debug) + printf("got it\n"); +#endif + return (n); +} |
