conf, tcp, udp: Allow specification of interface to bind to

Since kernel version 5.7, commit c427bfec18f2 ("net: core: enable
SO_BINDTODEVICE for non-root users"), we can bind sockets to
interfaces, if they haven't been bound yet (as in bind()).

Introduce an optional interface specification for forwarded ports,
prefixed by %, that can be passed together with an address.

Reported use case: running local services that use ports we want
to have externally forwarded:
  https://github.com/containers/podman/issues/14425

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 1 insertions, 1 deletions

diff --git a/tcp.h b/tcp.h
index 2548d4d..7ba7ab7 100644
--- a/tcp.h
+++ b/tcp.h
@@ -21,7 +21,7 @@ void tcp_sock_handler(struct ctx *c, union epoll_ref ref, uint32_t events,
 int tcp_tap_handler(struct ctx *c, int af, const void *addr,
 		    const struct pool *p, const struct timespec *now);
 void tcp_sock_init(const struct ctx *c, int ns, sa_family_t af,
-		   const void *addr, in_port_t port);
+		   const void *addr, const char *ifname, in_port_t port);
 int tcp_init(struct ctx *c);
 void tcp_timer(struct ctx *c, const struct timespec *ts);
 void tcp_defer_handler(struct ctx *c);