xref: /openbmc/linux/net/handshake/handshake.h (revision 2a598d0b)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Generic netlink handshake service
4  *
5  * Author: Chuck Lever <chuck.lever@oracle.com>
6  *
7  * Copyright (c) 2023, Oracle and/or its affiliates.
8  */
9 
10 #ifndef _INTERNAL_HANDSHAKE_H
11 #define _INTERNAL_HANDSHAKE_H
12 
13 /* Per-net namespace context */
14 struct handshake_net {
15 	spinlock_t		hn_lock;	/* protects next 3 fields */
16 	int			hn_pending;
17 	int			hn_pending_max;
18 	struct list_head	hn_requests;
19 
20 	unsigned long		hn_flags;
21 };
22 
23 enum hn_flags_bits {
24 	HANDSHAKE_F_NET_DRAINING,
25 };
26 
27 struct handshake_proto;
28 
29 /* One handshake request */
30 struct handshake_req {
31 	struct list_head		hr_list;
32 	struct rhash_head		hr_rhash;
33 	unsigned long			hr_flags;
34 	const struct handshake_proto	*hr_proto;
35 	struct sock			*hr_sk;
36 	void				(*hr_odestruct)(struct sock *sk);
37 
38 	/* Always the last field */
39 	char				hr_priv[];
40 };
41 
42 enum hr_flags_bits {
43 	HANDSHAKE_F_REQ_COMPLETED,
44 };
45 
46 /* Invariants for all handshake requests for one transport layer
47  * security protocol
48  */
49 struct handshake_proto {
50 	int			hp_handler_class;
51 	size_t			hp_privsize;
52 	unsigned long		hp_flags;
53 
54 	int			(*hp_accept)(struct handshake_req *req,
55 					     struct genl_info *info, int fd);
56 	void			(*hp_done)(struct handshake_req *req,
57 					   unsigned int status,
58 					   struct genl_info *info);
59 	void			(*hp_destroy)(struct handshake_req *req);
60 };
61 
62 enum hp_flags_bits {
63 	HANDSHAKE_F_PROTO_NOTIFY,
64 };
65 
66 /* netlink.c */
67 int handshake_genl_notify(struct net *net, const struct handshake_proto *proto,
68 			  gfp_t flags);
69 struct nlmsghdr *handshake_genl_put(struct sk_buff *msg,
70 				    struct genl_info *info);
71 struct handshake_net *handshake_pernet(struct net *net);
72 
73 /* request.c */
74 struct handshake_req *handshake_req_alloc(const struct handshake_proto *proto,
75 					  gfp_t flags);
76 int handshake_req_hash_init(void);
77 void handshake_req_hash_destroy(void);
78 void *handshake_req_private(struct handshake_req *req);
79 struct handshake_req *handshake_req_hash_lookup(struct sock *sk);
80 struct handshake_req *handshake_req_next(struct handshake_net *hn, int class);
81 int handshake_req_submit(struct socket *sock, struct handshake_req *req,
82 			 gfp_t flags);
83 void handshake_complete(struct handshake_req *req, unsigned int status,
84 			struct genl_info *info);
85 bool handshake_req_cancel(struct sock *sk);
86 
87 #endif /* _INTERNAL_HANDSHAKE_H */
88