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 <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/169047942074.5241.13791647439480672048.stgit@oracle-102.nfsv4bat.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Chuck Lever 2023-07-27 13:37:10 -04:00 committed by Jakub Kicinski
parent 5dd5ad682c
commit 39d0e38dcc
2 changed files with 46 additions and 0 deletions

View File

@ -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); bool tls_handshake_cancel(struct sock *sk);
void tls_handshake_close(struct socket *sock); 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 */ #endif /* _NET_HANDSHAKE_H */

View File

@ -59,3 +59,45 @@ int tls_alert_send(struct socket *sock, u8 level, u8 description)
ret = sock_sendmsg(sock, &msg); ret = sock_sendmsg(sock, &msg);
return ret < 0 ? ret : 0; 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);