kernel-netlink: Copy current usage stats to new SA in update_sa()

This is needed to fix usage stats sent via RADIUS Accounting if clients
use MOBIKE or e.g. the kernel notifies us about a changed NAT mapping.
The upper layers won't expect the stats to get reset if only the IPs have
changed (and some kernel interface might actually allow such updates
without reset).

It also fixes traffic based lifetimes in such situations.

Fixes #799.

1 files changed, 34 insertions, 6 deletions

diff --git a/src/libhydra/plugins/kernel_netlink/kernel_netlink_ipsec.c b/src/libhydra/plugins/kernel_netlink/kernel_netlink_ipsec.c
index 9534ef0c0..03e44e510 100644
--- a/src/libhydra/plugins/kernel_netlink/kernel_netlink_ipsec.c
+++ b/src/libhydra/plugins/kernel_netlink/kernel_netlink_ipsec.c
@@ -1550,7 +1550,8 @@ static void get_replay_state(private_kernel_netlink_ipsec_t *this,
 							 host_t *dst, mark_t mark,
 							 struct xfrm_replay_state_esn **replay_esn,
 							 u_int32_t *replay_esn_len,
-							 struct xfrm_replay_state **replay)
+							 struct xfrm_replay_state **replay,
+							 struct xfrm_lifetime_cur **lifetime)
 {
 	netlink_buf_t request;
 	struct nlmsghdr *hdr, *out = NULL;
@@ -1618,20 +1619,27 @@ static void get_replay_state(private_kernel_netlink_ipsec_t *this,
 		rtasize = XFRM_PAYLOAD(out, struct xfrm_aevent_id);
 		while (RTA_OK(rta, rtasize))
 		{
+			if (rta->rta_type == XFRMA_LTIME_VAL &&
+				RTA_PAYLOAD(rta) == sizeof(**lifetime))
+			{
+				free(*lifetime);
+				*lifetime = malloc(RTA_PAYLOAD(rta));
+				memcpy(*lifetime, RTA_DATA(rta), RTA_PAYLOAD(rta));
+			}
 			if (rta->rta_type == XFRMA_REPLAY_VAL &&
 				RTA_PAYLOAD(rta) == sizeof(**replay))
 			{
+				free(*replay);
 				*replay = malloc(RTA_PAYLOAD(rta));
 				memcpy(*replay, RTA_DATA(rta), RTA_PAYLOAD(rta));
-				break;
 			}
 			if (rta->rta_type == XFRMA_REPLAY_ESN_VAL &&
 				RTA_PAYLOAD(rta) >= sizeof(**replay_esn))
 			{
+				free(*replay_esn);
 				*replay_esn = malloc(RTA_PAYLOAD(rta));
 				*replay_esn_len = RTA_PAYLOAD(rta);
 				memcpy(*replay_esn, RTA_DATA(rta), RTA_PAYLOAD(rta));
-				break;
 			}
 			rta = RTA_NEXT(rta, rtasize);
 		}
@@ -1813,6 +1821,7 @@ METHOD(kernel_ipsec_t, update_sa, status_t,
 	struct xfrm_encap_tmpl* tmpl = NULL;
 	struct xfrm_replay_state *replay = NULL;
 	struct xfrm_replay_state_esn *replay_esn = NULL;
+	struct xfrm_lifetime_cur *lifetime = NULL;
 	u_int32_t replay_esn_len;
 	status_t status = FAILED;
 
@@ -1878,7 +1887,8 @@ METHOD(kernel_ipsec_t, update_sa, status_t,
 		goto failed;
 	}
 
-	get_replay_state(this, spi, protocol, dst, mark, &replay_esn, &replay_esn_len, &replay);
+	get_replay_state(this, spi, protocol, dst, mark, &replay_esn,
+					 &replay_esn_len, &replay, &lifetime);
 
 	/* delete the old SA (without affecting the IPComp SA) */
 	if (del_sa(this, src, dst, spi, protocol, 0, mark) != SUCCESS)
@@ -1967,8 +1977,25 @@ METHOD(kernel_ipsec_t, update_sa, status_t,
 	}
 	else
 	{
-		DBG1(DBG_KNL, "unable to copy replay state from old SAD entry "
-					  "with SPI %.8x", ntohl(spi));
+		DBG1(DBG_KNL, "unable to copy replay state from old SAD entry with "
+			 "SPI %.8x", ntohl(spi));
+	}
+	if (lifetime)
+	{
+		struct xfrm_lifetime_cur *state;
+
+		state = netlink_reserve(hdr, sizeof(request), XFRMA_LTIME_VAL,
+								sizeof(*state));
+		if (!state)
+		{
+			goto failed;
+		}
+		memcpy(state, lifetime, sizeof(*state));
+	}
+	else
+	{
+		DBG1(DBG_KNL, "unable to copy usage stats from old SAD entry with "
+			 "SPI %.8x", ntohl(spi));
 	}
 
 	if (this->socket_xfrm->send_ack(this->socket_xfrm, hdr) != SUCCESS)
@@ -1981,6 +2008,7 @@ METHOD(kernel_ipsec_t, update_sa, status_t,
 failed:
 	free(replay);
 	free(replay_esn);
+	free(lifetime);
 	memwipe(out, len);
 	memwipe(&request, sizeof(request));
 	free(out);