libbb:/send_to_from: do not require that "to" should have the same AF. Closes 9146

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2016-09-15 13:20:51 +02:00
parent 3a45b87ac3
commit 7cef4817d6

View File

@ -70,7 +70,13 @@ send_to_from(int fd, void *buf, size_t len, int flags,
msg.msg_flags = flags;
cmsgptr = CMSG_FIRSTHDR(&msg);
if (to->sa_family == AF_INET && from->sa_family == AF_INET) {
/*
* Users report that to->sa_family can be AF_INET6 too,
* if "to" was acquired by recv_from_to(). IOW: recv_from_to()
* was seen showing IPv6 "from" even when the destination
* of received packet (our local address) was IPv4.
*/
if (/* to->sa_family == AF_INET && */ from->sa_family == AF_INET) {
struct in_pktinfo *pktptr;
cmsgptr->cmsg_level = IPPROTO_IP;
cmsgptr->cmsg_type = IP_PKTINFO;
@ -86,7 +92,7 @@ send_to_from(int fd, void *buf, size_t len, int flags,
pktptr->ipi_spec_dst = ((struct sockaddr_in*)from)->sin_addr;
}
# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
else if (to->sa_family == AF_INET6 && from->sa_family == AF_INET6) {
else if (/* to->sa_family == AF_INET6 && */ from->sa_family == AF_INET6) {
struct in6_pktinfo *pktptr;
cmsgptr->cmsg_level = IPPROTO_IPV6;
cmsgptr->cmsg_type = IPV6_PKTINFO;