contrib: add osmo-upf-tunend.gtplab2.cfg

Support receiving of Echo Responses, so far showed an error log for
unsupported message type. Just log the message.

Prep for upcoming patch to allow sending Echo Requests from VTY.

Change-Id: Idad417746a1ea797e8fbfe04ca9c84923a6118fa

contrib/osmo-pfcp-tool-scripts/osmo-upf-12.cfg

@@ -23,3 +23,7 @@ pfcp
  local-addr 127.0.0.12
 tunmap
  table-name osmo-upf-12
+
+# gtp-dev only for GTP-U Echo service
+tunend
+ dev create gtp-echo-12 127.0.0.12

contrib/osmo-pfcp-tool-scripts/osmo-upf-tunend.gtplab2.cfg

@@ -0,0 +1,25 @@
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print category-hex 0
+ logging print category 1
+ logging timestamp 0
+ logging print file basename last
+ logging print level 1
+ logging level set-all notice
+ logging level set-all info
+ logging level session debug
+ logging level nft debug
+ logging level gtp debug
+#logging level set-all debug
+
+line vty
+ bind 127.0.0.2
+ctrl
+ bind 127.0.0.2
+
+timer pfcp x24 5000
+pfcp
+ local-addr 172.16.32.2
+tunend
+ dev create apn2 172.16.32.2

contrib/osmo-pfcp-tool-scripts/tunend_session_est.vty

@@ -1,5 +1,5 @@
 timer pfcp x23 0
-pfcp-peer 127.0.0.1
+pfcp-peer 127.0.0.11
  tx assoc-setup-req
  sleep 1
  session tunend

src/osmo-upf/upf_gtpu_echo.c

@@ -50,23 +50,43 @@ struct gtp1u_hdr {
 
 static int tx_echo_resp(struct upf_gtp_dev *dev, const struct osmo_sockaddr *remote, uint16_t seq_nr);
 
-static int rx_echo_req(struct upf_gtp_dev *dev, const struct osmo_sockaddr *remote, const struct gtp1u_hdr *rx_h)
+static int rx_echo_req(struct upf_gtp_dev *dev, const struct osmo_sockaddr *remote, const struct gtp1u_hdr *rx_h,
+		       size_t msg_len)
 {
-	if (!rx_h->s) {
-		LOG_GTP_DEV(dev, LOGL_ERROR, "rx GTPv1-U ECHO REQ without sequence nr\n");
-		return -1;
-	}
+	uint16_t seq_nr = 0;
+	uint8_t recovery_count = 0;
+	if (msg_len >= (sizeof(*rx_h) + 2) && rx_h->data2[0] == GTP1U_IEI_RECOVERY)
+		recovery_count = rx_h->data2[1];
+
+	seq_nr = rx_h->s;
+	LOG_GTP_DEV(dev, LOGL_INFO, "<- %s: rx GTPv1-U Echo Request: seq_nr=%u recovery_count=%u\n",
+		    osmo_sockaddr_to_str(remote), seq_nr, recovery_count);
 
 	return tx_echo_resp(dev, remote, rx_h->ext.seq_nr);
 }
 
+static void rx_echo_resp(struct upf_gtp_dev *dev, const struct osmo_sockaddr *remote, const struct gtp1u_hdr *rx_h,
+			 size_t msg_len)
+{
+	if (msg_len < (sizeof(*rx_h) + 2)) {
+		LOG_GTP_DEV(dev, LOGL_ERROR,
+			    "<- %s: rx GTPv1-U Echo Response, but message is too short (%zu < %zu)\n",
+			    osmo_sockaddr_to_str_c(OTC_SELECT, remote), msg_len, (sizeof(*rx_h) + 2));
+		return;
+	}
+
+	uint8_t recovery_count = rx_h->data2[1];
+	LOG_GTP_DEV(dev, LOGL_INFO, "<- %s: rx GTPv1-U Echo Response: seq_nr=%u recovery_count=%u\n",
+		    osmo_sockaddr_to_str(remote), rx_h->ext.seq_nr, recovery_count);
+}
+
 static int tx_echo_resp(struct upf_gtp_dev *dev, const struct osmo_sockaddr *remote, uint16_t seq_nr)
 {
 	struct msgb *msg;
 	struct gtp1u_hdr *tx_h;
 	int rc;
 
-	msg = msgb_alloc_headroom(1024, 128, "GTP-echo-resp");
+	msg = msgb_alloc_headroom(1024, 128, "GTPv1-U-echo-resp");
 	tx_h = (void *)msgb_put(msg, sizeof(*tx_h));
 
 	*tx_h = (struct gtp1u_hdr){
@@ -90,10 +110,15 @@ static int tx_echo_resp(struct upf_gtp_dev *dev, const struct osmo_sockaddr *rem
 
 	rc = sendto(dev->gtpv1.ofd.fd, msgb_data(msg), msgb_length(msg), 0, &remote->u.sa, sizeof(*remote));
 	if (rc < 0) {
-		int err = errno;
-		LOG_GTP_DEV(dev, LOGL_ERROR, "GTP1-U sendto(len=%d, to=%s): %s\n", msgb_length(msg),
-			    osmo_sockaddr_to_str(remote), strerror(err));
+		rc = -errno;
+		LOG_GTP_DEV(dev, LOGL_ERROR, "-> %s: tx GTPv1-U Echo Response: sendto(len=%d): %s\n",
+			    osmo_sockaddr_to_str(remote), msgb_length(msg), strerror(-rc));
+	} else {
+		LOG_GTP_DEV(dev, LOGL_INFO, "-> %s: tx GTPv1-U Echo Response: seq_nr=%u recovery_count=%u\n",
+			    osmo_sockaddr_to_str(remote), seq_nr, g_upf->tunend.recovery_count);
+		rc = 0;
 	}
+	msgb_free(msg);
 	return rc;
 }
 
@@ -120,39 +145,42 @@ int upf_gtpu_echo_read_cb(struct osmo_fd *ofd, unsigned int what)
 	/* A GTPv1-U header of size 8 is valid, but this code expects to handle only ECHO REQUEST messages. These are
 	 * required to have a sequence number, hence this check here consciously uses the full sizeof(*h) == 12. */
 	if (sz < sizeof(*h)) {
-		LOG_GTP_DEV(dev, LOGL_ERROR, "rx GTP packet smaller than the GTPv1-U header + sequence nr: %zd < %zu\n",
-			    sz, sizeof(*h));
+		LOG_GTP_DEV(dev, LOGL_ERROR,
+			    "<- %s: rx GTPv1-U packet smaller than the GTPv1-U header + sequence nr: %zd < %zu\n",
+			    osmo_sockaddr_to_str(&remote), sz, sizeof(*h));
 		return -1;
 	}
 
 	h = (const struct gtp1u_hdr *)buf;
 	if (h->version != 1) {
-		LOG_GTP_DEV(dev, LOGL_ERROR, "rx GTP v%u: only GTP version 1 supported\n", h->version);
+		LOG_GTP_DEV(dev, LOGL_ERROR, "<- %s: rx GTPv1-U v%u: only GTP version 1 supported\n",
+			    osmo_sockaddr_to_str(&remote), h->version);
 		return -1;
 	}
 
 	h_length = osmo_load16be(&h->length);
 	if (offsetof(struct gtp1u_hdr, data1) + h_length > sz) {
-		LOG_GTP_DEV(dev, LOGL_ERROR, "rx GTP: header + h.length = %zu > received bytes = %zd\n",
-			    offsetof(struct gtp1u_hdr, data1) + h_length, sz);
+		LOG_GTP_DEV(dev, LOGL_ERROR, "<- %s: rx GTPv1-U: header + h.length = %zu > received bytes = %zd\n",
+			    osmo_sockaddr_to_str(&remote), offsetof(struct gtp1u_hdr, data1) + h_length, sz);
 		return -1;
 	}
 
 	switch (h->msg_type) {
 	case GTP1U_MSGTYPE_ECHO_REQ:
-		return rx_echo_req(dev, &remote, h);
+		return rx_echo_req(dev, &remote, h, sz);
+	case GTP1U_MSGTYPE_ECHO_RSP:
+		rx_echo_resp(dev, &remote, h, sz);
+		return 0;
 	default:
 		LOG_GTP_DEV(dev, LOGL_ERROR, "rx: GTPv1-U message type %u not supported\n", h->msg_type);
 		return -1;
 	}
-
-	return 0;
 }
 
 int upf_gtpu_echo_setup(struct upf_gtp_dev *dev)
 {
 	if (dev->gtpv1.ofd.fd == -1) {
-		LOGP(DGTP, LOGL_ERROR, "Cannot setup GTP-U ECHO: GTP-v1 socket not initialized\n");
+		LOGP(DGTP, LOGL_ERROR, "Cannot setup GTPv1-U ECHO: socket not initialized\n");
 		return -EINVAL;
 	}
 

tests/Makefile.am

@@ -21,7 +21,7 @@ $(srcdir)/package.m4: $(top_srcdir)/configure.ac
              } >'$(srcdir)/package.m4'
 
 EXTRA_DIST = \
-	upf.vty \
+	$(srcdir)/*.vty \
 	testsuite.at \
 	$(srcdir)/package.m4 \
 	$(TESTSUITE) \