SUNRPC: Use new helpers to handle TLS Alerts

Use the helpers to parse the level and description fields in
incoming alerts. "Warning" alerts are discarded, and "fatal"
alerts mean the session is no longer valid.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/169047944747.5241.1974889594004407123.stgit@oracle-102.nfsv4bat.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 25 insertions, 22 deletions

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index cca6ee716020..2ed29e40c6a9 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -43,7 +43,6 @@
 #include <net/udp.h>
 #include <net/tcp.h>
 #include <net/tcp_states.h>
-#include <net/tls.h>
 #include <net/tls_prot.h>
 #include <net/handshake.h>
 #include <linux/uaccess.h>
@@ -227,27 +226,30 @@ static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
 }
 
 static int
-svc_tcp_sock_process_cmsg(struct svc_sock *svsk, struct msghdr *msg,
+svc_tcp_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
 			  struct cmsghdr *cmsg, int ret)
 {
-	if (cmsg->cmsg_level == SOL_TLS &&
-	    cmsg->cmsg_type == TLS_GET_RECORD_TYPE) {
-		u8 content_type = *((u8 *)CMSG_DATA(cmsg));
-
-		switch (content_type) {
-		case TLS_RECORD_TYPE_DATA:
-			/* TLS sets EOR at the end of each application data
-			 * record, even though there might be more frames
-			 * waiting to be decrypted.
-			 */
-			msg->msg_flags &= ~MSG_EOR;
-			break;
-		case TLS_RECORD_TYPE_ALERT:
-			ret = -ENOTCONN;
-			break;
-		default:
-			ret = -EAGAIN;
-		}
+	u8 content_type = tls_get_record_type(sock->sk, cmsg);
+	u8 level, description;
+
+	switch (content_type) {
+	case 0:
+		break;
+	case TLS_RECORD_TYPE_DATA:
+		/* TLS sets EOR at the end of each application data
+		 * record, even though there might be more frames
+		 * waiting to be decrypted.
+		 */
+		msg->msg_flags &= ~MSG_EOR;
+		break;
+	case TLS_RECORD_TYPE_ALERT:
+		tls_alert_recv(sock->sk, msg, &level, &description);
+		ret = (level == TLS_ALERT_LEVEL_FATAL) ?
+			-ENOTCONN : -EAGAIN;
+		break;
+	default:
+		/* discard this record type */
+		ret = -EAGAIN;
 	}
 	return ret;
 }
@@ -259,13 +261,14 @@ svc_tcp_sock_recv_cmsg(struct svc_sock *svsk, struct msghdr *msg)
 		struct cmsghdr	cmsg;
 		u8		buf[CMSG_SPACE(sizeof(u8))];
 	} u;
+	struct socket *sock = svsk->sk_sock;
 	int ret;
 
 	msg->msg_control = &u;
 	msg->msg_controllen = sizeof(u);
-	ret = sock_recvmsg(svsk->sk_sock, msg, MSG_DONTWAIT);
+	ret = sock_recvmsg(sock, msg, MSG_DONTWAIT);
 	if (unlikely(msg->msg_controllen != sizeof(u)))
-		ret = svc_tcp_sock_process_cmsg(svsk, msg, &u.cmsg, ret);
+		ret = svc_tcp_sock_process_cmsg(sock, msg, &u.cmsg, ret);
 	return ret;
 }