niansa-misc/musl
1
0
Fork 0
mirror of git://git.musl-libc.org/musl synced 2025-03-06 20:48:29 +01:00
Code Issues Projects Releases Packages Wiki Activity

properly handle point-to-point interfaces in getifaddrs()

Browse source 
With point-to-point interfaces, the IFA_ADDRESS netlink attribute
contains the peer address while an extra attribute IFA_LOCAL carries
the actual local interface address.

Both the glibc and uclibc implementations of getifaddrs() handle this
case by moving the ifa_addr contents to the broadcast/remote address
union and overwriting ifa_addr upon receipt of an IFA_LOCAL attribute.

This patch adds the same special treatment logic of IFA_LOCAL to
musl's implementation of getifaddrs() in order to align its behaviour
with that of uclibc and glibc.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>
This commit is contained in:
Jo-Philipp Wich 2015-11-19 21:43:10 +01:00 • committed by Rich Felker
parent 12978acb30
commit 7b712844e3
1 changed files with 16 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
src/network/getifaddrs.c
View file

@ -162,13 +162,26 @@ static int netlink_msg_to_ifaddr(void *pctx, struct nlmsghdr *h)
for (rta = NLMSG_RTA(h, sizeof(*ifa)); NLMSG_RTAOK(rta, h); rta = RTA_NEXT(rta)) {
switch (rta->rta_type) {
case IFA_ADDRESS:
copy_addr(&ifs->ifa.ifa_addr, ifa->ifa_family, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
/* If ifa_addr is already set we, received an IFA_LOCAL before
* so treat this as destination address */
if (ifs->ifa.ifa_addr)
copy_addr(&ifs->ifa.ifa_dstaddr, ifa->ifa_family, &ifs->ifu, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
else
copy_addr(&ifs->ifa.ifa_addr, ifa->ifa_family, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
break;
case IFA_BROADCAST:
/* For point-to-point links this is peer, but ifa_broadaddr
* and ifa_dstaddr are union, so this works for both. */
copy_addr(&ifs->ifa.ifa_broadaddr, ifa->ifa_family, &ifs->ifu, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
break;
case IFA_LOCAL:
/* If ifa_addr is set and we get IFA_LOCAL, assume we have
* a point-to-point network. Move address to correct field. */
if (ifs->ifa.ifa_addr) {
ifs->ifu = ifs->addr;
ifs->ifa.ifa_dstaddr = &ifs->ifu.sa;
memset(&ifs->addr, 0, sizeof(ifs->addr));
}
copy_addr(&ifs->ifa.ifa_addr, ifa->ifa_family, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
break;
case IFA_LABEL:
if (RTA_DATALEN(rta) < sizeof(ifs->name)) {
memcpy(ifs->name, RTA_DATA(rta), RTA_DATALEN(rta));