Each entry udp_splice_map[v6][N] keeps information about two essentially
unrelated packet flows. @ns_conn_sock, @ns_conn_ts and @init_bound_sock
track a packet flow from port N in the host init namespace to some other
port in the pasta namespace (the one @ns_conn_sock is connected to).
@init_conn_sock, @init_conn_ts and @ns_bound_sock track packet flow from
port N in the pasta namespace to some other port in the host init namespace
(the one @init_conn_sock is connected to).
Split udp_splice_map[][] into two separate tables for the two directions.
Each entry in each table is a 'struct udp_splice_flow' with @orig_sock
(previously the bound socket), @target_sock (previously the connected
socket) and @ts (the timeout for the target socket).
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
udp.c | 111 +++++++++++++++++++++++++++++-----------------------------
1 file changed, 56 insertions(+), 55 deletions(-)
diff --git a/udp.c b/udp.c
index a025a48..4caf73e 100644
--- a/udp.c
+++ b/udp.c
@@ -47,44 +47,44 @@
*
* - forward direction: 127.0.0.1:5000 -> 127.0.0.1:80 in init from bound
* socket s, with epoll reference: index = 80, splice = UDP_TO_NS
- * - if udp_splice_map[V4][5000].ns_conn_sock:
- * - send packet to udp4_splice_map[5000].ns_conn_sock
+ * - if udp_splice_to_ns[V4][5000].target_sock:
+ * - send packet to udp_splice_to_ns[V4][5000].target_sock
* - otherwise:
- * - create new socket udp_splice_map[V4][5000].ns_conn_sock
+ * - create new socket udp_splice_to_ns[V4][5000].target_sock
* - bind in namespace to 127.0.0.1:5000
* - connect in namespace to 127.0.0.1:80 (note: this destination port
* might be remapped to another port instead)
* - add to epoll with reference: index = 5000, splice: UDP_BACK_TO_INIT
- * - set udp_splice_map[V4][5000].init_bound_sock to s
- * - update udp_splice_map[V4][5000].ns_conn_ts with current time
+ * - set udp_splice_to_ns[V4][5000].orig_sock to s
+ * - update udp_splice_to_ns[V4][5000].ts with current time
*
* - reverse direction: 127.0.0.1:80 -> 127.0.0.1:5000 in namespace from
* connected socket s, having epoll reference: index = 5000,
* splice = UDP_BACK_TO_INIT
- * - if udp_splice_map[V4][5000].init_bound_sock:
- * - send to udp_splice_map[V4][5000].init_bound_sock, with destination
- * port 5000
+ * - if udp_splice_to_ns[V4][5000].orig_sock:
+ * - send to udp_splice_to_ns[V4][5000].orig_sock, with destination port
+ * 5000
* - otherwise, discard
*
* - from namespace to init:
*
* - forward direction: 127.0.0.1:2000 -> 127.0.0.1:22 in namespace from bound
* socket s, with epoll reference: index = 22, splice = UDP_TO_INIT
- * - if udp4_splice_map[V4][2000].init_conn_sock:
- * - send packet to udp4_splice_map[2000].init_conn_sock
+ * - if udp4_splice_to_init[V4][2000].target_sock:
+ * - send packet to udp_splice_to_init[V4][2000].target_sock
* - otherwise:
- * - create new socket udp_splice_map[V4][2000].init_conn_sock
+ * - create new socket udp_splice_to_init[V4][2000].target_sock
* - bind in init to 127.0.0.1:2000
* - connect in init to 127.0.0.1:22 (note: this destination port
* might be remapped to another port instead)
* - add to epoll with reference: index = 2000, splice = UDP_BACK_TO_NS
- * - set udp_splice_map[V4][2000].ns_bound_sock to s
- * - update udp_splice_map[V4][2000].init_conn_ts with current time
+ * - set udp_splice_to_init[V4][2000].orig_sock to s
+ * - update udp_splice_to_init[V4][2000].ts with current time
*
* - reverse direction: 127.0.0.1:22 -> 127.0.0.1:2000 in init from connected
* socket s, having epoll reference: index = 2000, splice = UDP_BACK_TO_NS
- * - if udp_splice_map[V4][2000].ns_bound_sock:
- * - send to udp_splice_map[V4][2000].ns_bound_sock, with destination port
+ * - if udp_splice_to_init[V4][2000].orig_sock:
+ * - send to udp_splice_to_init[V4][2000].orig_sock, with destination port
* 2000
* - otherwise, discard
*/
@@ -138,28 +138,26 @@ struct udp_tap_port {
};
/**
- * struct udp_splice_port - Source port tracking for traffic between namespaces
- * @ns_conn_sock: Socket connected in namespace for init source port
- * @init_conn_sock: Socket connected in init for namespace source port
- * @ns_conn_ts: Timestamp of activity for socket connected in namespace
- * @init_conn_ts: Timestamp of activity for socket connceted in init
- * @ns_bound_sock: Bound socket in namespace for this source port in init
- * @init_bound_sock: Bound socket in init for this source port in namespace
+ * struct udp_splice_flow - Spliced "connection"
+ * @orig_sock: Originating socket, bound to dest port in source ns of
+ * originating datagram
+ * @target_sock: Target socket, bound to source port of originating
+ * datagram in dest ns, connected to dest port of
+ * originating datagram in dest ns
+ * @ts: Activity timestamp
*/
-struct udp_splice_port {
- int ns_conn_sock;
- int init_conn_sock;
-
- time_t ns_conn_ts;
- time_t init_conn_ts;
-
- int ns_bound_sock;
- int init_bound_sock;
+struct udp_splice_flow {
+ int orig_sock;
+ int target_sock;
+ time_t ts;
};
/* Port tracking, arrays indexed by packet source port (host order) */
static struct udp_tap_port udp_tap_map [IP_VERSIONS][NUM_PORTS];
-static struct udp_splice_port udp_splice_map [IP_VERSIONS][NUM_PORTS];
+
+/* Spliced "connections" indexed by originating source port (host order) */
+static struct udp_splice_flow udp_splice_to_ns [IP_VERSIONS][NUM_PORTS];
+static struct udp_splice_flow udp_splice_to_init[IP_VERSIONS][NUM_PORTS];
enum udp_act_type {
UDP_ACT_TAP,
@@ -421,8 +419,17 @@ int udp_splice_connect(const struct ctx *c, int v6, int bound_sock,
.r.p.udp.udp = { .splice = splice, .v6 = v6,
.port = src }
};
- struct udp_splice_port *sp = &udp_splice_map[v6 ? V6 : V4][src];
+ struct udp_splice_flow *flow;
int s;
+ int act;
+
+ if (splice == UDP_BACK_TO_INIT) {
+ flow = &udp_splice_to_ns[v6 ? V6 : V4][src];
+ act = UDP_ACT_NS_CONN;
+ } else {
+ flow = &udp_splice_to_init[v6 ? V6 : V4][src];
+ act = UDP_ACT_INIT_CONN;
+ }
s = socket(v6 ? AF_INET6 : AF_INET, SOCK_DGRAM | SOCK_NONBLOCK,
IPPROTO_UDP);
@@ -461,15 +468,9 @@ int udp_splice_connect(const struct ctx *c, int v6, int bound_sock,
goto fail;
}
- if (splice == UDP_BACK_TO_INIT) {
- sp->init_bound_sock = bound_sock;
- sp->ns_conn_sock = s;
- bitmap_set(udp_act[v6 ? V6 : V4][UDP_ACT_NS_CONN], src);
- } else if (splice == UDP_BACK_TO_NS) {
- sp->ns_bound_sock = bound_sock;
- sp->init_conn_sock = s;
- bitmap_set(udp_act[v6 ? V6 : V4][UDP_ACT_INIT_CONN], src);
- }
+ flow->orig_sock = bound_sock;
+ flow->target_sock = s;
+ bitmap_set(udp_act[v6 ? V6 : V4][act], src);
ev.data.u64 = ref.u64;
epoll_ctl(c->epollfd, EPOLL_CTL_ADD, s, &ev);
@@ -556,7 +557,7 @@ static void udp_sock_handler_splice(const struct ctx *c, union
epoll_ref ref,
case UDP_TO_NS:
src += c->udp.fwd_out.rdelta[src];
- if (!(s = udp_splice_map[v6][src].ns_conn_sock)) {
+ if (!(s = udp_splice_to_ns[v6][src].target_sock)) {
struct udp_splice_connect_ns_arg arg = {
c, v6, ref.r.s, src, dst, -1,
};
@@ -565,10 +566,10 @@ static void udp_sock_handler_splice(const struct ctx *c, union
epoll_ref ref,
if ((s = arg.s) < 0)
return;
}
- udp_splice_map[v6][src].ns_conn_ts = now->tv_sec;
+ udp_splice_to_ns[v6][src].ts = now->tv_sec;
break;
case UDP_BACK_TO_INIT:
- if (!(s = udp_splice_map[v6][dst].init_bound_sock))
+ if (!(s = udp_splice_to_ns[v6][dst].orig_sock))
return;
send_dst = dst;
@@ -576,16 +577,16 @@ static void udp_sock_handler_splice(const struct ctx *c, union
epoll_ref ref,
case UDP_TO_INIT:
src += c->udp.fwd_in.rdelta[src];
- if (!(s = udp_splice_map[v6][src].init_conn_sock)) {
+ if (!(s = udp_splice_to_init[v6][src].target_sock)) {
s = udp_splice_connect(c, v6, ref.r.s, src, dst,
UDP_BACK_TO_NS);
if (s < 0)
return;
}
- udp_splice_map[v6][src].init_conn_ts = now->tv_sec;
+ udp_splice_to_init[v6][src].ts = now->tv_sec;
break;
case UDP_BACK_TO_NS:
- if (!(s = udp_splice_map[v6][dst].ns_bound_sock))
+ if (!(s = udp_splice_to_init[v6][dst].orig_sock))
return;
send_dst = dst;
@@ -1286,7 +1287,7 @@ int udp_init(struct ctx *c)
static void udp_timer_one(struct ctx *c, int v6, enum udp_act_type type,
in_port_t port, const struct timespec *ts)
{
- struct udp_splice_port *sp;
+ struct udp_splice_flow *flow;
struct udp_tap_port *tp;
int s = -1;
@@ -1301,17 +1302,17 @@ static void udp_timer_one(struct ctx *c, int v6, enum udp_act_type
type,
break;
case UDP_ACT_INIT_CONN:
- sp = &udp_splice_map[v6 ? V6 : V4][port];
+ flow = &udp_splice_to_init[v6 ? V6 : V4][port];
- if (ts->tv_sec - sp->init_conn_ts > UDP_CONN_TIMEOUT)
- s = sp->init_conn_sock;
+ if (ts->tv_sec - flow->ts > UDP_CONN_TIMEOUT)
+ s = flow->target_sock;
break;
case UDP_ACT_NS_CONN:
- sp = &udp_splice_map[v6 ? V6 : V4][port];
+ flow = &udp_splice_to_ns[v6 ? V6 : V4][port];
- if (ts->tv_sec - sp->ns_conn_ts > UDP_CONN_TIMEOUT)
- s = sp->ns_conn_sock;
+ if (ts->tv_sec - flow->ts > UDP_CONN_TIMEOUT)
+ s = flow->target_sock;
break;
default:
--
2.38.1