mirrors/passt
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

udp: Don't use separate sockets to listen for spliced packets

Browse source 
Currently, when ports are forwarded inbound in pasta mode, we open two
sockets for incoming traffic: one listens on the public IP address and will
forward packets to the tuntap interface.  The other listens on localhost
and forwards via "splicing" (resending directly via sockets in the ns).

Now that we've improved the logic about whether we "splice" any individual
packet, we don't need this.  Instead we can have a single socket bound to
0.0.0.0 or ::, marked as able to splice and udp_sock_handler() will deal
with each packet as appropriate.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson 2023-01-05 15:26:25 +11:00 committed by Stefano Brivio
parent 8d503e825f
commit b93d025d50
1 changed files with 13 additions and 40 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

53
udp.c
View file

@ -1124,7 +1124,6 @@ void udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
const void *addr, const char *ifname, in_port_t port) const void *addr, const char *ifname, in_port_t port)
{ {
union udp_epoll_ref uref = { .u32 = 0 }; union udp_epoll_ref uref = { .u32 = 0 };
const void *bind_addr;
int s; int s;
if (ns) { if (ns) {
@ -1136,67 +1135,41 @@ void udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
} }
if ((af == AF_INET || af == AF_UNSPEC) && c->ifi4) { if ((af == AF_INET || af == AF_UNSPEC) && c->ifi4) {
if (!addr && c->mode == MODE_PASTA)
bind_addr = &c->ip4.addr;
else
bind_addr = addr;
uref.udp.v6 = 0; uref.udp.v6 = 0;
uref.udp.splice = (c->mode == MODE_PASTA);
uref.udp.orig = true;
if (!ns) { if (!ns) {
uref.udp.splice = 0; s = sock_l4(c, AF_INET, IPPROTO_UDP, addr, ifname,
s = sock_l4(c, AF_INET, IPPROTO_UDP, bind_addr, ifname,
port, uref.u32); port, uref.u32);
udp_tap_map[V4][uref.udp.port].sock = s; udp_tap_map[V4][uref.udp.port].sock = s;
udp_splice_init[V4][port].sock = s;
if (c->mode == MODE_PASTA) {
bind_addr = &(uint32_t){ htonl(INADDR_LOOPBACK) };
uref.udp.splice = uref.udp.orig = true;
s = sock_l4(c, AF_INET, IPPROTO_UDP, bind_addr,
ifname, port, uref.u32);
udp_splice_init[V4][port].sock = s;
}
} else { } else {
uref.udp.splice = uref.udp.orig = uref.udp.ns = true; struct in_addr loopback = { htonl(INADDR_LOOPBACK) };
uref.udp.ns = true;
bind_addr = &(uint32_t){ htonl(INADDR_LOOPBACK) }; s = sock_l4(c, AF_INET, IPPROTO_UDP, &loopback,
s = sock_l4(c, AF_INET, IPPROTO_UDP, bind_addr,
ifname, port, uref.u32); ifname, port, uref.u32);
udp_splice_ns[V4][port].sock = s; udp_splice_ns[V4][port].sock = s;
} }
} }
if ((af == AF_INET6 || af == AF_UNSPEC) && c->ifi6) { if ((af == AF_INET6 || af == AF_UNSPEC) && c->ifi6) {
if (!addr && c->mode == MODE_PASTA)
bind_addr = &c->ip6.addr;
else
bind_addr = addr;
uref.udp.v6 = 1; uref.udp.v6 = 1;
uref.udp.splice = (c->mode == MODE_PASTA);
uref.udp.orig = true;
if (!ns) { if (!ns) {
uref.udp.splice = 0; s = sock_l4(c, AF_INET6, IPPROTO_UDP, addr, ifname,
s = sock_l4(c, AF_INET6, IPPROTO_UDP, bind_addr, ifname,
port, uref.u32); port, uref.u32);
udp_tap_map[V6][uref.udp.port].sock = s; udp_tap_map[V6][uref.udp.port].sock = s;
udp_splice_init[V6][port].sock = s;
if (c->mode == MODE_PASTA) {
bind_addr = &in6addr_loopback;
uref.udp.splice = uref.udp.orig = true;
s = sock_l4(c, AF_INET6, IPPROTO_UDP, bind_addr,
ifname, port, uref.u32);
udp_splice_init[V6][port].sock = s;
}
} else { } else {
bind_addr = &in6addr_loopback; uref.udp.ns = true;
uref.udp.splice = uref.udp.orig = uref.udp.ns = true;
s = sock_l4(c, AF_INET6, IPPROTO_UDP, bind_addr, s = sock_l4(c, AF_INET6, IPPROTO_UDP, &in6addr_loopback,
ifname, port, uref.u32); ifname, port, uref.u32);
udp_splice_ns[V6][port].sock = s; udp_splice_ns[V6][port].sock = s;
} }