1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Handle the TLS Alert protocol |
4 | * |
5 | * Author: Chuck Lever <chuck.lever@oracle.com> |
6 | * |
7 | * Copyright (c) 2023, Oracle and/or its affiliates. |
8 | */ |
9 | |
10 | #include <linux/types.h> |
11 | #include <linux/socket.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/module.h> |
14 | #include <linux/skbuff.h> |
15 | #include <linux/inet.h> |
16 | |
17 | #include <net/sock.h> |
18 | #include <net/handshake.h> |
19 | #include <net/tls.h> |
20 | #include <net/tls_prot.h> |
21 | |
22 | #include "handshake.h" |
23 | |
24 | #include <trace/events/handshake.h> |
25 | |
26 | /** |
27 | * tls_alert_send - send a TLS Alert on a kTLS socket |
28 | * @sock: open kTLS socket to send on |
29 | * @level: TLS Alert level |
30 | * @description: TLS Alert description |
31 | * |
32 | * Returns zero on success or a negative errno. |
33 | */ |
34 | int tls_alert_send(struct socket *sock, u8 level, u8 description) |
35 | { |
36 | u8 record_type = TLS_RECORD_TYPE_ALERT; |
37 | u8 buf[CMSG_SPACE(sizeof(record_type))]; |
38 | struct msghdr msg = { 0 }; |
39 | struct cmsghdr *cmsg; |
40 | struct kvec iov; |
41 | u8 alert[2]; |
42 | int ret; |
43 | |
44 | trace_tls_alert_send(sk: sock->sk, level, description); |
45 | |
46 | alert[0] = level; |
47 | alert[1] = description; |
48 | iov.iov_base = alert; |
49 | iov.iov_len = sizeof(alert); |
50 | |
51 | memset(buf, 0, sizeof(buf)); |
52 | msg.msg_control = buf; |
53 | msg.msg_controllen = sizeof(buf); |
54 | msg.msg_flags = MSG_DONTWAIT; |
55 | |
56 | cmsg = CMSG_FIRSTHDR(&msg); |
57 | cmsg->cmsg_level = SOL_TLS; |
58 | cmsg->cmsg_type = TLS_SET_RECORD_TYPE; |
59 | cmsg->cmsg_len = CMSG_LEN(sizeof(record_type)); |
60 | memcpy(CMSG_DATA(cmsg), &record_type, sizeof(record_type)); |
61 | |
62 | iov_iter_kvec(i: &msg.msg_iter, ITER_SOURCE, kvec: &iov, nr_segs: 1, count: iov.iov_len); |
63 | ret = sock_sendmsg(sock, msg: &msg); |
64 | return ret < 0 ? ret : 0; |
65 | } |
66 | |
67 | /** |
68 | * tls_get_record_type - Look for TLS RECORD_TYPE information |
69 | * @sk: socket (for IP address information) |
70 | * @cmsg: incoming message to be parsed |
71 | * |
72 | * Returns zero or a TLS_RECORD_TYPE value. |
73 | */ |
74 | u8 tls_get_record_type(const struct sock *sk, const struct cmsghdr *cmsg) |
75 | { |
76 | u8 record_type; |
77 | |
78 | if (cmsg->cmsg_level != SOL_TLS) |
79 | return 0; |
80 | if (cmsg->cmsg_type != TLS_GET_RECORD_TYPE) |
81 | return 0; |
82 | |
83 | record_type = *((u8 *)CMSG_DATA(cmsg)); |
84 | trace_tls_contenttype(sk, type: record_type); |
85 | return record_type; |
86 | } |
87 | EXPORT_SYMBOL(tls_get_record_type); |
88 | |
89 | /** |
90 | * tls_alert_recv - Parse TLS Alert messages |
91 | * @sk: socket (for IP address information) |
92 | * @msg: incoming message to be parsed |
93 | * @level: OUT - TLS AlertLevel value |
94 | * @description: OUT - TLS AlertDescription value |
95 | * |
96 | */ |
97 | void tls_alert_recv(const struct sock *sk, const struct msghdr *msg, |
98 | u8 *level, u8 *description) |
99 | { |
100 | const struct kvec *iov; |
101 | u8 *data; |
102 | |
103 | iov = msg->msg_iter.kvec; |
104 | data = iov->iov_base; |
105 | *level = data[0]; |
106 | *description = data[1]; |
107 | |
108 | trace_tls_alert_recv(sk, level: *level, description: *description); |
109 | } |
110 | EXPORT_SYMBOL(tls_alert_recv); |
111 | |