[IPVS]: ip_vs_ftp breaks connections using persistence
ip_vs_ftp when loaded can create NAT connections with unknown client
port for passive FTP. For such expectations we lookup with cport=0 on
incoming packet but it matches the format of the persistence templates
causing packets to other persistent virtual servers to be forwarded to
real server without creating connection. Later the reply packets are
treated as foreign and not SNAT-ed.
This patch changes the connection lookup for packets from clients:
* introduce IP_VS_CONN_F_TEMPLATE connection flag to mark the
connection as template
* create new connection lookup function just for templates -
ip_vs_ct_in_get
* make sure ip_vs_conn_in_get hits only connections with
IP_VS_CONN_F_NO_CPORT flag set when s_port is 0. By this way
we avoid returning template when looking for cport=0 (ftp)
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ipvs/ip_vs_sync.c b/net/ipv4/ipvs/ip_vs_sync.c
index 574d1f5..2e5ced3 100644
--- a/net/ipv4/ipvs/ip_vs_sync.c
+++ b/net/ipv4/ipvs/ip_vs_sync.c
@@ -297,16 +297,24 @@
p = (char *)buffer + sizeof(struct ip_vs_sync_mesg);
for (i=0; i<m->nr_conns; i++) {
+ unsigned flags;
+
s = (struct ip_vs_sync_conn *)p;
- cp = ip_vs_conn_in_get(s->protocol,
- s->caddr, s->cport,
- s->vaddr, s->vport);
+ flags = ntohs(s->flags);
+ if (!(flags & IP_VS_CONN_F_TEMPLATE))
+ cp = ip_vs_conn_in_get(s->protocol,
+ s->caddr, s->cport,
+ s->vaddr, s->vport);
+ else
+ cp = ip_vs_ct_in_get(s->protocol,
+ s->caddr, s->cport,
+ s->vaddr, s->vport);
if (!cp) {
cp = ip_vs_conn_new(s->protocol,
s->caddr, s->cport,
s->vaddr, s->vport,
s->daddr, s->dport,
- ntohs(s->flags), NULL);
+ flags, NULL);
if (!cp) {
IP_VS_ERR("ip_vs_conn_new failed\n");
return;
@@ -315,11 +323,11 @@
} else if (!cp->dest) {
/* it is an entry created by the synchronization */
cp->state = ntohs(s->state);
- cp->flags = ntohs(s->flags) | IP_VS_CONN_F_HASHED;
+ cp->flags = flags | IP_VS_CONN_F_HASHED;
} /* Note that we don't touch its state and flags
if it is a normal entry. */
- if (ntohs(s->flags) & IP_VS_CONN_F_SEQ_MASK) {
+ if (flags & IP_VS_CONN_F_SEQ_MASK) {
opt = (struct ip_vs_sync_conn_options *)&s[1];
memcpy(&cp->in_seq, opt, sizeof(*opt));
p += FULL_CONN_SIZE;