From b32fd3cc31d723bf2ab859667be3612c0086ec72 Mon Sep 17 00:00:00 2001
From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Fri, 4 Oct 2019 16:19:25 -0700
Subject: [PATCH] net/tls: add statistics for installed sessions

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>
---
 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(-)

diff --git a/Documentation/networking/tls.rst b/Documentation/networking/tls.rst
index a6ee595630eda..cfba587af5c95 100644
--- 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
diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index 4abd57948ad45..1b4613b5af70e 100644
--- 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
 };
 
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index 686eba0df5908..f144b965704e7 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -286,14 +286,19 @@ static void tls_sk_proto_cleanup(struct sock *sk,
 		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)
@@ -534,19 +539,29 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 	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);
diff --git a/net/tls/tls_proc.c b/net/tls/tls_proc.c
index 4ecc7c35d2f71..1b1f3783badc2 100644
--- 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
 };
 
-- 
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