From 39d0e38dcced8d4da92cd11f3ff618bacc42d8a9 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 27 Jul 2023 13:37:10 -0400 Subject: [PATCH] net/handshake: Add helpers for parsing incoming TLS Alerts Kernel TLS consumers can replace common TLS Alert parsing code with these helpers. Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/169047942074.5241.13791647439480672048.stgit@oracle-102.nfsv4bat.org Signed-off-by: Jakub Kicinski --- include/net/handshake.h | 4 ++++ net/handshake/alert.c | 42 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+) diff --git a/include/net/handshake.h b/include/net/handshake.h index bb88dfa6e3c9..8ebd4f9ed26e 100644 --- a/include/net/handshake.h +++ b/include/net/handshake.h @@ -42,4 +42,8 @@ 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 */ diff --git a/net/handshake/alert.c b/net/handshake/alert.c index 2f1a16868ff6..286bf94d93a3 100644 --- a/net/handshake/alert.c +++ b/net/handshake/alert.c @@ -59,3 +59,45 @@ int tls_alert_send(struct socket *sock, u8 level, u8 description) 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)); + 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]; +} +EXPORT_SYMBOL(tls_alert_recv);