From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Fri, 4 Oct 2019 16:19:25 -0700
Subject: net/tls: add statistics for installed sessions
Patch-mainline: v5.5-rc1
Git-commit: b32fd3cc31d723bf2ab859667be3612c0086ec72
References: bsc#1154353

Add SNMP stats for number of sockets with successfully
installed sessions.  Break them down to software and
hardware ones.  Note that if hardware offload fails
stack uses software implementation, and counts the
session appropriately.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 Documentation/networking/tls.rst |   14 ++++++++++++++
 include/uapi/linux/snmp.h        |    8 ++++++++
 net/tls/tls_main.c               |   23 +++++++++++++++++++----
 net/tls/tls_proc.c               |    8 ++++++++
 4 files changed, 49 insertions(+), 4 deletions(-)

--- a/Documentation/networking/tls.rst
+++ b/Documentation/networking/tls.rst
@@ -219,3 +219,17 @@ Statistics
 
 TLS implementation exposes the following per-namespace statistics
 (``/proc/net/tls_stat``):
+
+- ``TlsCurrTxSw``, ``TlsCurrRxSw`` -
+  number of TX and RX sessions currently installed where host handles
+  cryptography
+
+- ``TlsCurrTxDevice``, ``TlsCurrRxDevice`` -
+  number of TX and RX sessions currently installed where NIC handles
+  cryptography
+
+- ``TlsTxSw``, ``TlsRxSw`` -
+  number of TX and RX sessions opened with host cryptography
+
+- ``TlsTxDevice``, ``TlsRxDevice`` -
+  number of TX and RX sessions opened with NIC cryptography
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -327,6 +327,14 @@ enum
 enum
 {
 	LINUX_MIB_TLSNUM = 0,
+	LINUX_MIB_TLSCURRTXSW,			/* TlsCurrTxSw */
+	LINUX_MIB_TLSCURRRXSW,			/* TlsCurrRxSw */
+	LINUX_MIB_TLSCURRTXDEVICE,		/* TlsCurrTxDevice */
+	LINUX_MIB_TLSCURRRXDEVICE,		/* TlsCurrRxDevice */
+	LINUX_MIB_TLSTXSW,			/* TlsTxSw */
+	LINUX_MIB_TLSRXSW,			/* TlsRxSw */
+	LINUX_MIB_TLSTXDEVICE,			/* TlsTxDevice */
+	LINUX_MIB_TLSRXDEVICE,			/* TlsRxDevice */
 	__LINUX_MIB_TLSMAX
 };
 
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -287,14 +287,19 @@ static void tls_sk_proto_cleanup(struct
 		kfree(ctx->tx.rec_seq);
 		kfree(ctx->tx.iv);
 		tls_sw_release_resources_tx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 	} else if (ctx->tx_conf == TLS_HW) {
 		tls_device_free_resources_tx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 	}
 
-	if (ctx->rx_conf == TLS_SW)
+	if (ctx->rx_conf == TLS_SW) {
 		tls_sw_release_resources_rx(sk);
-	else if (ctx->rx_conf == TLS_HW)
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
+	} else if (ctx->rx_conf == TLS_HW) {
 		tls_device_offload_cleanup_rx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
+	}
 }
 
 static void tls_sk_proto_close(struct sock *sk, long timeout)
@@ -535,19 +540,29 @@ static int do_tls_setsockopt_conf(struct
 	if (tx) {
 		rc = tls_set_device_offload(sk, ctx);
 		conf = TLS_HW;
-		if (rc) {
+		if (!rc) {
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
+		} else {
 			rc = tls_set_sw_offload(sk, ctx, 1);
 			if (rc)
 				goto err_crypto_info;
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 			conf = TLS_SW;
 		}
 	} else {
 		rc = tls_set_device_offload_rx(sk, ctx);
 		conf = TLS_HW;
-		if (rc) {
+		if (!rc) {
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
+		} else {
 			rc = tls_set_sw_offload(sk, ctx, 0);
 			if (rc)
 				goto err_crypto_info;
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 			conf = TLS_SW;
 		}
 		tls_sw_strparser_arm(sk, ctx);
--- a/net/tls/tls_proc.c
+++ b/net/tls/tls_proc.c
@@ -7,6 +7,14 @@
 #include <net/tls.h>
 
 static const struct snmp_mib tls_mib_list[] = {
+	SNMP_MIB_ITEM("TlsCurrTxSw", LINUX_MIB_TLSCURRTXSW),
+	SNMP_MIB_ITEM("TlsCurrRxSw", LINUX_MIB_TLSCURRRXSW),
+	SNMP_MIB_ITEM("TlsCurrTxDevice", LINUX_MIB_TLSCURRTXDEVICE),
+	SNMP_MIB_ITEM("TlsCurrRxDevice", LINUX_MIB_TLSCURRRXDEVICE),
+	SNMP_MIB_ITEM("TlsTxSw", LINUX_MIB_TLSTXSW),
+	SNMP_MIB_ITEM("TlsRxSw", LINUX_MIB_TLSRXSW),
+	SNMP_MIB_ITEM("TlsTxDevice", LINUX_MIB_TLSTXDEVICE),
+	SNMP_MIB_ITEM("TlsRxDevice", LINUX_MIB_TLSRXDEVICE),
 	SNMP_MIB_SENTINEL
 };