Merge branch 'in-kernel-support-for-the-tls-alert-protocol'

Chuck Lever says:

====================
In-kernel support for the TLS Alert protocol

IMO the kernel doesn't need user space (ie, tlshd) to handle the TLS
Alert protocol. Instead, a set of small helper functions can be used
to handle sending and receiving TLS Alerts for in-kernel TLS
consumers.
====================

Merged on top of a tag in case it's needed in the NFS tree.

Link: https://lore.kernel.org/r/169047923706.5241.1181144206068116926.stgit@oracle-102.nfsv4bat.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls.h

@@ -22,6 +22,7 @@
 #include <crypto/internal/hash.h>
 #include <linux/tls.h>
 #include <net/tls.h>
+#include <net/tls_prot.h>
 #include <net/tls_toe.h>
 
 #include "t4fw_api.h"

include/net/handshake.h

@@ -40,5 +40,10 @@ int tls_server_hello_x509(const struct tls_handshake_args *args, gfp_t flags);
 int tls_server_hello_psk(const struct tls_handshake_args *args, gfp_t flags);
 
 bool tls_handshake_cancel(struct sock *sk);
+void tls_handshake_close(struct socket *sock);
+
+u8 tls_get_record_type(const struct sock *sk, const struct cmsghdr *msg);
+void tls_alert_recv(const struct sock *sk, const struct msghdr *msg,
+		    u8 *level, u8 *description);
 
 #endif /* _NET_HANDSHAKE_H */

include/net/tls.h

@@ -69,10 +69,6 @@ extern const struct tls_cipher_size_desc tls_cipher_size_desc[];
 
 #define TLS_CRYPTO_INFO_READY(info)	((info)->cipher_type)
 
-#define TLS_RECORD_TYPE_ALERT		0x15
-#define TLS_RECORD_TYPE_HANDSHAKE	0x16
-#define TLS_RECORD_TYPE_DATA		0x17
-
 #define TLS_AAD_SPACE_SIZE		13
 
 #define MAX_IV_SIZE			16

include/net/tls_prot.h

@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates.
+ *
+ * TLS Protocol definitions
+ *
+ * From https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml
+ */
+
+#ifndef _TLS_PROT_H
+#define _TLS_PROT_H
+
+/*
+ * TLS Record protocol: ContentType
+ */
+enum {
+	TLS_RECORD_TYPE_CHANGE_CIPHER_SPEC = 20,
+	TLS_RECORD_TYPE_ALERT = 21,
+	TLS_RECORD_TYPE_HANDSHAKE = 22,
+	TLS_RECORD_TYPE_DATA = 23,
+	TLS_RECORD_TYPE_HEARTBEAT = 24,
+	TLS_RECORD_TYPE_TLS12_CID = 25,
+	TLS_RECORD_TYPE_ACK = 26,
+};
+
+/*
+ * TLS Alert protocol: AlertLevel
+ */
+enum {
+	TLS_ALERT_LEVEL_WARNING = 1,
+	TLS_ALERT_LEVEL_FATAL = 2,
+};
+
+/*
+ * TLS Alert protocol: AlertDescription
+ */
+enum {
+	TLS_ALERT_DESC_CLOSE_NOTIFY = 0,
+	TLS_ALERT_DESC_UNEXPECTED_MESSAGE = 10,
+	TLS_ALERT_DESC_BAD_RECORD_MAC = 20,
+	TLS_ALERT_DESC_RECORD_OVERFLOW = 22,
+	TLS_ALERT_DESC_HANDSHAKE_FAILURE = 40,
+	TLS_ALERT_DESC_BAD_CERTIFICATE = 42,
+	TLS_ALERT_DESC_UNSUPPORTED_CERTIFICATE = 43,
+	TLS_ALERT_DESC_CERTIFICATE_REVOKED = 44,
+	TLS_ALERT_DESC_CERTIFICATE_EXPIRED = 45,
+	TLS_ALERT_DESC_CERTIFICATE_UNKNOWN = 46,
+	TLS_ALERT_DESC_ILLEGAL_PARAMETER = 47,
+	TLS_ALERT_DESC_UNKNOWN_CA = 48,
+	TLS_ALERT_DESC_ACCESS_DENIED = 49,
+	TLS_ALERT_DESC_DECODE_ERROR = 50,
+	TLS_ALERT_DESC_DECRYPT_ERROR = 51,
+	TLS_ALERT_DESC_TOO_MANY_CIDS_REQUESTED	= 52,
+	TLS_ALERT_DESC_PROTOCOL_VERSION = 70,
+	TLS_ALERT_DESC_INSUFFICIENT_SECURITY = 71,
+	TLS_ALERT_DESC_INTERNAL_ERROR = 80,
+	TLS_ALERT_DESC_INAPPROPRIATE_FALLBACK = 86,
+	TLS_ALERT_DESC_USER_CANCELED = 90,
+	TLS_ALERT_DESC_MISSING_EXTENSION = 109,
+	TLS_ALERT_DESC_UNSUPPORTED_EXTENSION = 110,
+	TLS_ALERT_DESC_UNRECOGNIZED_NAME = 112,
+	TLS_ALERT_DESC_BAD_CERTIFICATE_STATUS_RESPONSE = 113,
+	TLS_ALERT_DESC_UNKNOWN_PSK_IDENTITY = 115,
+	TLS_ALERT_DESC_CERTIFICATE_REQUIRED = 116,
+	TLS_ALERT_DESC_NO_APPLICATION_PROTOCOL = 120,
+};
+
+#endif /* _TLS_PROT_H */

include/trace/events/handshake.h

@@ -6,7 +6,86 @@
 #define _TRACE_HANDSHAKE_H
 
 #include <linux/net.h>
+#include <net/tls_prot.h>
 #include <linux/tracepoint.h>
+#include <trace/events/net_probe_common.h>
+
+#define TLS_RECORD_TYPE_LIST \
+	record_type(CHANGE_CIPHER_SPEC) \
+	record_type(ALERT) \
+	record_type(HANDSHAKE) \
+	record_type(DATA) \
+	record_type(HEARTBEAT) \
+	record_type(TLS12_CID) \
+	record_type_end(ACK)
+
+#undef record_type
+#undef record_type_end
+#define record_type(x)		TRACE_DEFINE_ENUM(TLS_RECORD_TYPE_##x);
+#define record_type_end(x)	TRACE_DEFINE_ENUM(TLS_RECORD_TYPE_##x);
+
+TLS_RECORD_TYPE_LIST
+
+#undef record_type
+#undef record_type_end
+#define record_type(x)		{ TLS_RECORD_TYPE_##x, #x },
+#define record_type_end(x)	{ TLS_RECORD_TYPE_##x, #x }
+
+#define show_tls_content_type(type) \
+	__print_symbolic(type, TLS_RECORD_TYPE_LIST)
+
+TRACE_DEFINE_ENUM(TLS_ALERT_LEVEL_WARNING);
+TRACE_DEFINE_ENUM(TLS_ALERT_LEVEL_FATAL);
+
+#define show_tls_alert_level(level) \
+	__print_symbolic(level, \
+		{ TLS_ALERT_LEVEL_WARNING,	"Warning" }, \
+		{ TLS_ALERT_LEVEL_FATAL,	"Fatal" })
+
+#define TLS_ALERT_DESCRIPTION_LIST \
+	alert_description(CLOSE_NOTIFY) \
+	alert_description(UNEXPECTED_MESSAGE) \
+	alert_description(BAD_RECORD_MAC) \
+	alert_description(RECORD_OVERFLOW) \
+	alert_description(HANDSHAKE_FAILURE) \
+	alert_description(BAD_CERTIFICATE) \
+	alert_description(UNSUPPORTED_CERTIFICATE) \
+	alert_description(CERTIFICATE_REVOKED) \
+	alert_description(CERTIFICATE_EXPIRED) \
+	alert_description(CERTIFICATE_UNKNOWN) \
+	alert_description(ILLEGAL_PARAMETER) \
+	alert_description(UNKNOWN_CA) \
+	alert_description(ACCESS_DENIED) \
+	alert_description(DECODE_ERROR) \
+	alert_description(DECRYPT_ERROR) \
+	alert_description(TOO_MANY_CIDS_REQUESTED) \
+	alert_description(PROTOCOL_VERSION) \
+	alert_description(INSUFFICIENT_SECURITY) \
+	alert_description(INTERNAL_ERROR) \
+	alert_description(INAPPROPRIATE_FALLBACK) \
+	alert_description(USER_CANCELED) \
+	alert_description(MISSING_EXTENSION) \
+	alert_description(UNSUPPORTED_EXTENSION) \
+	alert_description(UNRECOGNIZED_NAME) \
+	alert_description(BAD_CERTIFICATE_STATUS_RESPONSE) \
+	alert_description(UNKNOWN_PSK_IDENTITY) \
+	alert_description(CERTIFICATE_REQUIRED) \
+	alert_description_end(NO_APPLICATION_PROTOCOL)
+
+#undef alert_description
+#undef alert_description_end
+#define alert_description(x)		TRACE_DEFINE_ENUM(TLS_ALERT_DESC_##x);
+#define alert_description_end(x)	TRACE_DEFINE_ENUM(TLS_ALERT_DESC_##x);
+
+TLS_ALERT_DESCRIPTION_LIST
+
+#undef alert_description
+#undef alert_description_end
+#define alert_description(x)		{ TLS_ALERT_DESC_##x, #x },
+#define alert_description_end(x)	{ TLS_ALERT_DESC_##x, #x }
+
+#define show_tls_alert_description(desc) \
+	__print_symbolic(desc, TLS_ALERT_DESCRIPTION_LIST)
 
 DECLARE_EVENT_CLASS(handshake_event_class,
 	TP_PROTO(
@@ -106,6 +185,47 @@ DECLARE_EVENT_CLASS(handshake_error_class,
 		),						\
 		TP_ARGS(net, req, sk, err))
 
+DECLARE_EVENT_CLASS(handshake_alert_class,
+	TP_PROTO(
+		const struct sock *sk,
+		unsigned char level,
+		unsigned char description
+	),
+	TP_ARGS(sk, level, description),
+	TP_STRUCT__entry(
+		/* sockaddr_in6 is always bigger than sockaddr_in */
+		__array(__u8, saddr, sizeof(struct sockaddr_in6))
+		__array(__u8, daddr, sizeof(struct sockaddr_in6))
+		__field(unsigned int, netns_ino)
+		__field(unsigned long, level)
+		__field(unsigned long, description)
+	),
+	TP_fast_assign(
+		const struct inet_sock *inet = inet_sk(sk);
+
+		memset(__entry->saddr, 0, sizeof(struct sockaddr_in6));
+		memset(__entry->daddr, 0, sizeof(struct sockaddr_in6));
+		TP_STORE_ADDR_PORTS(__entry, inet, sk);
+
+		__entry->netns_ino = sock_net(sk)->ns.inum;
+		__entry->level = level;
+		__entry->description = description;
+	),
+	TP_printk("src=%pISpc dest=%pISpc %s: %s",
+		__entry->saddr, __entry->daddr,
+		show_tls_alert_level(__entry->level),
+		show_tls_alert_description(__entry->description)
+	)
+);
+#define DEFINE_HANDSHAKE_ALERT(name)				\
+	DEFINE_EVENT(handshake_alert_class, name,		\
+		TP_PROTO(					\
+			const struct sock *sk,			\
+			unsigned char level,			\
+			unsigned char description		\
+		),						\
+		TP_ARGS(sk, level, description))
+
 
 /*
  * Request lifetime events
@@ -154,6 +274,46 @@ DEFINE_HANDSHAKE_ERROR(handshake_cmd_accept_err);
 DEFINE_HANDSHAKE_FD_EVENT(handshake_cmd_done);
 DEFINE_HANDSHAKE_ERROR(handshake_cmd_done_err);
 
+/*
+ * TLS Record events
+ */
+
+TRACE_EVENT(tls_contenttype,
+	TP_PROTO(
+		const struct sock *sk,
+		unsigned char type
+	),
+	TP_ARGS(sk, type),
+	TP_STRUCT__entry(
+		/* sockaddr_in6 is always bigger than sockaddr_in */
+		__array(__u8, saddr, sizeof(struct sockaddr_in6))
+		__array(__u8, daddr, sizeof(struct sockaddr_in6))
+		__field(unsigned int, netns_ino)
+		__field(unsigned long, type)
+	),
+	TP_fast_assign(
+		const struct inet_sock *inet = inet_sk(sk);
+
+		memset(__entry->saddr, 0, sizeof(struct sockaddr_in6));
+		memset(__entry->daddr, 0, sizeof(struct sockaddr_in6));
+		TP_STORE_ADDR_PORTS(__entry, inet, sk);
+
+		__entry->netns_ino = sock_net(sk)->ns.inum;
+		__entry->type = type;
+	),
+	TP_printk("src=%pISpc dest=%pISpc %s",
+		__entry->saddr, __entry->daddr,
+		show_tls_content_type(__entry->type)
+	)
+);
+
+/*
+ * TLS Alert events
+ */
+
+DEFINE_HANDSHAKE_ALERT(tls_alert_send);
+DEFINE_HANDSHAKE_ALERT(tls_alert_recv);
+
 #endif /* _TRACE_HANDSHAKE_H */
 
 #include <trace/define_trace.h>

net/handshake/Makefile

@@ -8,6 +8,6 @@
 #
 
 obj-y += handshake.o
-handshake-y := genl.o netlink.o request.o tlshd.o trace.o
+handshake-y := alert.o genl.o netlink.o request.o tlshd.o trace.o
 
 obj-$(CONFIG_NET_HANDSHAKE_KUNIT_TEST) += handshake-test.o

net/handshake/alert.c

@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Handle the TLS Alert protocol
+ *
+ * Author: Chuck Lever <chuck.lever@oracle.com>
+ *
+ * Copyright (c) 2023, Oracle and/or its affiliates.
+ */
+
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/inet.h>
+
+#include <net/sock.h>
+#include <net/handshake.h>
+#include <net/tls.h>
+#include <net/tls_prot.h>
+
+#include "handshake.h"
+
+#include <trace/events/handshake.h>
+
+/**
+ * tls_alert_send - send a TLS Alert on a kTLS socket
+ * @sock: open kTLS socket to send on
+ * @level: TLS Alert level
+ * @description: TLS Alert description
+ *
+ * Returns zero on success or a negative errno.
+ */
+int tls_alert_send(struct socket *sock, u8 level, u8 description)
+{
+	u8 record_type = TLS_RECORD_TYPE_ALERT;
+	u8 buf[CMSG_SPACE(sizeof(record_type))];
+	struct msghdr msg = { 0 };
+	struct cmsghdr *cmsg;
+	struct kvec iov;
+	u8 alert[2];
+	int ret;
+
+	trace_tls_alert_send(sock->sk, level, description);
+
+	alert[0] = level;
+	alert[1] = description;
+	iov.iov_base = alert;
+	iov.iov_len = sizeof(alert);
+
+	memset(buf, 0, sizeof(buf));
+	msg.msg_control = buf;
+	msg.msg_controllen = sizeof(buf);
+	msg.msg_flags = MSG_DONTWAIT;
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	cmsg->cmsg_level = SOL_TLS;
+	cmsg->cmsg_type = TLS_SET_RECORD_TYPE;
+	cmsg->cmsg_len = CMSG_LEN(sizeof(record_type));
+	memcpy(CMSG_DATA(cmsg), &record_type, sizeof(record_type));
+
+	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, iov.iov_len);
+	ret = sock_sendmsg(sock, &msg);
+	return ret < 0 ? ret : 0;
+}
+
+/**
+ * tls_get_record_type - Look for TLS RECORD_TYPE information
+ * @sk: socket (for IP address information)
+ * @cmsg: incoming message to be parsed
+ *
+ * Returns zero or a TLS_RECORD_TYPE value.
+ */
+u8 tls_get_record_type(const struct sock *sk, const struct cmsghdr *cmsg)
+{
+	u8 record_type;
+
+	if (cmsg->cmsg_level != SOL_TLS)
+		return 0;
+	if (cmsg->cmsg_type != TLS_GET_RECORD_TYPE)
+		return 0;
+
+	record_type = *((u8 *)CMSG_DATA(cmsg));
+	trace_tls_contenttype(sk, record_type);
+	return record_type;
+}
+EXPORT_SYMBOL(tls_get_record_type);
+
+/**
+ * tls_alert_recv - Parse TLS Alert messages
+ * @sk: socket (for IP address information)
+ * @msg: incoming message to be parsed
+ * @level: OUT - TLS AlertLevel value
+ * @description: OUT - TLS AlertDescription value
+ *
+ */
+void tls_alert_recv(const struct sock *sk, const struct msghdr *msg,
+		    u8 *level, u8 *description)
+{
+	const struct kvec *iov;
+	u8 *data;
+
+	iov = msg->msg_iter.kvec;
+	data = iov->iov_base;
+	*level = data[0];
+	*description = data[1];
+
+	trace_tls_alert_recv(sk, *level, *description);
+}
+EXPORT_SYMBOL(tls_alert_recv);