diff options
| -rw-r--r-- | sys/netinet/if_ether.c | 87 |
1 files changed, 48 insertions, 39 deletions
diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c index d1d4c959074..37f932f3fe9 100644 --- a/sys/netinet/if_ether.c +++ b/sys/netinet/if_ether.c @@ -1,4 +1,4 @@ -/* $OpenBSD: if_ether.c,v 1.212 2016/06/06 07:01:37 mpi Exp $ */ +/* $OpenBSD: if_ether.c,v 1.213 2016/06/06 07:07:11 mpi Exp $ */ /* $NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $ */ /* @@ -84,6 +84,7 @@ struct rtentry *arplookup(struct in_addr *, int, int, unsigned int); void in_arpinput(struct ifnet *, struct mbuf *); void in_revarpinput(struct ifnet *, struct mbuf *); int arpcache(struct ifnet *, struct ether_arp *, struct rtentry *); +void arpreply(struct ifnet *, struct mbuf *, struct in_addr *, uint8_t *); LIST_HEAD(, llinfo_arp) arp_list; struct pool arp_pool; /* pool for llinfo_arp structures */ @@ -255,6 +256,33 @@ arprequest(struct ifnet *ifp, u_int32_t *sip, u_int32_t *tip, u_int8_t *enaddr) ifp->if_output(ifp, m, &sa, NULL); } +void +arpreply(struct ifnet *ifp, struct mbuf *m, struct in_addr *sip, uint8_t *eaddr) +{ + struct ether_header *eh; + struct ether_arp *ea; + struct sockaddr sa; + + ea = mtod(m, struct ether_arp *); + ea->arp_op = htons(ARPOP_REPLY); + ea->arp_pro = htons(ETHERTYPE_IP); /* let's be sure! */ + + /* We're replying to a request. */ + memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha)); + memcpy(ea->arp_tpa, ea->arp_spa, sizeof(ea->arp_spa)); + + memcpy(ea->arp_sha, eaddr, sizeof(ea->arp_sha)); + memcpy(ea->arp_spa, sip, sizeof(ea->arp_spa)); + + eh = (struct ether_header *)sa.sa_data; + memcpy(eh->ether_dhost, ea->arp_tha, sizeof(eh->ether_dhost)); + memcpy(eh->ether_shost, eaddr, sizeof(eh->ether_shost)); + eh->ether_type = htons(ETHERTYPE_ARP); + sa.sa_family = pseudo_AF_HDRCMPLT; + sa.sa_len = sizeof(sa); + ifp->if_output(ifp, m, &sa, NULL); +} + /* * Resolve an IP address into an ethernet address. If success, * desten is filled in. If there is no entry in arptab, @@ -421,12 +449,9 @@ void in_arpinput(struct ifnet *ifp, struct mbuf *m) { struct ether_arp *ea; - struct ether_header *eh; struct rtentry *rt = NULL; - struct sockaddr sa; struct sockaddr_in sin; struct in_addr isaddr, itaddr; - uint8_t enaddr[ETHER_ADDR_LEN]; char addr[INET_ADDRSTRLEN]; int op, target = 0; unsigned int rdomain; @@ -452,8 +477,7 @@ in_arpinput(struct ifnet *ifp, struct mbuf *m) goto out; } - memcpy(enaddr, LLADDR(ifp->if_sadl), ETHER_ADDR_LEN); - if (!memcmp(ea->arp_sha, enaddr, sizeof(ea->arp_sha))) + if (!memcmp(ea->arp_sha, LLADDR(ifp->if_sadl), sizeof(ea->arp_sha))) goto out; /* it's from me, ignore it. */ /* Check target against our interface addresses. */ @@ -486,43 +510,28 @@ in_arpinput(struct ifnet *ifp, struct mbuf *m) goto out; } - if (op != ARPOP_REQUEST) - goto out; - - rtfree(rt); - if (target) { - /* We are the target and already have all info for the reply */ - memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha)); - memcpy(ea->arp_sha, LLADDR(ifp->if_sadl), sizeof(ea->arp_sha)); - } else { - struct sockaddr_dl *sdl; + if (op == ARPOP_REQUEST) { + uint8_t *eaddr; - rt = arplookup(&itaddr, 0, SIN_PROXY, rdomain); - if (rt == NULL) - goto out; - /* protect from possible duplicates only owner should respond */ - if (rt->rt_ifidx != ifp->if_index) - goto out; - memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha)); - sdl = satosdl(rt->rt_gateway); - memcpy(ea->arp_sha, LLADDR(sdl), sizeof(ea->arp_sha)); + if (target) { + /* We already have all info for the reply */ + eaddr = LLADDR(ifp->if_sadl); + } else { + rtfree(rt); + rt = arplookup(&itaddr, 0, SIN_PROXY, rdomain); + /* + * Protect from possible duplicates, only owner + * should respond + */ + if ((rt == NULL) || (rt->rt_ifidx != ifp->if_index)) + goto out; + eaddr = LLADDR(satosdl(rt->rt_gateway)); + } + arpreply(ifp, m, &itaddr, eaddr); rtfree(rt); + return; } - memcpy(ea->arp_tpa, ea->arp_spa, sizeof(ea->arp_spa)); - memcpy(ea->arp_spa, &itaddr, sizeof(ea->arp_spa)); - ea->arp_op = htons(ARPOP_REPLY); - ea->arp_pro = htons(ETHERTYPE_IP); /* let's be sure! */ - eh = (struct ether_header *)sa.sa_data; - memcpy(eh->ether_dhost, ea->arp_tha, sizeof(eh->ether_dhost)); - memcpy(eh->ether_shost, enaddr, sizeof(eh->ether_shost)); - - eh->ether_type = htons(ETHERTYPE_ARP); - sa.sa_family = pseudo_AF_HDRCMPLT; - sa.sa_len = sizeof(sa); - ifp->if_output(ifp, m, &sa, NULL); - return; - out: rtfree(rt); m_freem(m); |