int
arp_EtherAddr(struct in_addr ipaddr, struct sockaddr_dl *hwaddr,
int verbose)
{
int mib[6], skip;
size_t needed;
char *buf, *ptr, *end;
struct if_msghdr *ifm;
struct ifa_msghdr *ifam;
struct sockaddr_dl *dl;
struct sockaddr *sa[RTAX_MAX];
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = 0;
mib[4] = NET_RT_IFLIST;
mib[5] = 0;
if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) {
log_Printf(LogERROR, "arp_EtherAddr: sysctl: estimate: %s\n",
strerror(errno));
return 0;
}
if ((buf = malloc(needed)) == NULL)
return 0;
if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
free(buf);
return 0;
}
end = buf + needed;
ptr = buf;
while (ptr < end) {
ifm = (struct if_msghdr *)ptr; /* On if_msghdr */
if (ifm->ifm_type != RTM_IFINFO)
break;
dl = (struct sockaddr_dl *)(ifm + 1); /* Single _dl at end */
skip = (ifm->ifm_flags & (IFF_UP | IFF_BROADCAST | IFF_POINTOPOINT |
IFF_NOARP | IFF_LOOPBACK)) != (IFF_UP | IFF_BROADCAST);
ptr += ifm->ifm_msglen; /* First ifa_msghdr */
while (ptr < end) {
ifam = (struct ifa_msghdr *)ptr; /* Next ifa_msghdr (alias) */
if (ifam->ifam_type != RTM_NEWADDR) /* finished ? */
break;
ptr += ifam->ifam_msglen;
if (skip || (ifam->ifam_addrs & (RTA_NETMASK|RTA_IFA)) !=
(RTA_NETMASK|RTA_IFA))
continue;
/* Found a candidate. Do the addresses match ? */
if (log_IsKept(LogDEBUG) &&
ptr == (char *)ifm + ifm->ifm_msglen + ifam->ifam_msglen)
log_Printf(LogDEBUG, "%.*s interface is a candidate for proxy\n",
dl->sdl_nlen, dl->sdl_data);
iface_ParseHdr(ifam, sa);
if (sa[RTAX_IFA]->sa_family == AF_INET) {
struct sockaddr_in *ifa, *netmask;
ifa = (struct sockaddr_in *)sa[RTAX_IFA];
netmask = (struct sockaddr_in *)sa[RTAX_NETMASK];
if (log_IsKept(LogDEBUG)) {
char a[16];
strncpy(a, inet_ntoa(netmask->sin_addr), sizeof a - 1);
a[sizeof a - 1] = '\0';
log_Printf(LogDEBUG, "Check addr %s, mask %s\n",
inet_ntoa(ifa->sin_addr), a);
}
if ((ifa->sin_addr.s_addr & netmask->sin_addr.s_addr) ==
(ipaddr.s_addr & netmask->sin_addr.s_addr)) {
log_Printf(verbose ? LogPHASE : LogDEBUG,
"Found interface %.*s for %s\n", dl->sdl_nlen,
dl->sdl_data, inet_ntoa(ipaddr));
memcpy(hwaddr, dl, dl->sdl_len);
free(buf);
return 1;
}
}
}
}
free(buf);
return 0;
}
struct iface *
iface_Create(const char *name)
{
int mib[6], maxtries, err;
size_t needed, namelen;
char *buf, *ptr, *end;
struct if_msghdr *ifm;
struct ifa_msghdr *ifam;
struct sockaddr_dl *dl;
struct sockaddr *sa[RTAX_MAX];
struct iface *iface;
struct iface_addr *addr;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = 0;
mib[4] = NET_RT_IFLIST;
mib[5] = 0;
maxtries = 20;
err = 0;
do {
if (maxtries-- == 0 || (err && err != ENOMEM)) {
fprintf(stderr, "iface_Create: sysctl: %s\n", strerror(err));
return NULL;
}
if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) {
fprintf(stderr, "iface_Create: sysctl: estimate: %s\n",
strerror(errno));
return NULL;
}
if ((buf = (char *)malloc(needed)) == NULL) {
fprintf(stderr, "iface_Create: malloc failed: %s\n", strerror(errno));
return NULL;
}
if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
err = errno;
free(buf);
buf = NULL;
}
} while (buf == NULL);
ptr = buf;
end = buf + needed;
iface = NULL;
namelen = strlen(name);
while (ptr < end && iface == NULL) {
ifm = (struct if_msghdr *)ptr; /* On if_msghdr */
if (ifm->ifm_type != RTM_IFINFO)
break;
dl = (struct sockaddr_dl *)(ifm + 1); /* Single _dl at end */
if (dl->sdl_nlen == namelen && !strncmp(name, dl->sdl_data, namelen)) {
iface = (struct iface *)malloc(sizeof *iface);
if (iface == NULL) {
fprintf(stderr, "iface_Create: malloc: %s\n", strerror(errno));
return NULL;
}
iface->name = strdup(name);
iface->descr = NULL;
iface->index = ifm->ifm_index;
iface->flags = ifm->ifm_flags;
iface->mtu = 0;
iface->addrs = 0;
iface->addr = NULL;
}
ptr += ifm->ifm_msglen; /* First ifa_msghdr */
for (; ptr < end; ptr += ifam->ifam_msglen) {
ifam = (struct ifa_msghdr *)ptr; /* Next if address */
if (ifam->ifam_type != RTM_NEWADDR) /* finished this if */
break;
if (iface != NULL && ifam->ifam_addrs & RTA_IFA) {
/* Found a configured interface ! */
iface_ParseHdr(ifam, sa);
if (sa[RTAX_IFA] && (sa[RTAX_IFA]->sa_family == AF_INET
#ifndef NOINET6
|| sa[RTAX_IFA]->sa_family == AF_INET6
#endif
)) {
/* Record the address */
addr = (struct iface_addr *)
realloc(iface->addr, (iface->addrs + 1) * sizeof iface->addr[0]);
if (addr == NULL)
break;
iface->addr = addr;
addr += iface->addrs;
iface->addrs++;
ncprange_setsa(&addr->ifa, sa[RTAX_IFA], sa[RTAX_NETMASK]);
if (sa[RTAX_BRD])
ncpaddr_setsa(&addr->peer, sa[RTAX_BRD]);
else
ncpaddr_init(&addr->peer);
}
}
}
}
free(buf);
return iface;
}
