net/handshake/handshake.h

   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         struct file                     *hr_file;
  35         const struct handshake_proto    *hr_proto;
  36         struct sock                     *hr_sk;
  37         void                            (*hr_odestruct)(struct sock *sk);
  38
  39         /* Always the last field */
  40         char                            hr_priv[];
  41 };
  42
  43 enum hr_flags_bits {
  44         HANDSHAKE_F_REQ_COMPLETED,
  45 };
  46
  47 /* Invariants for all handshake requests for one transport layer
  48  * security protocol
  49  */
  50 struct handshake_proto {
  51         int                     hp_handler_class;
  52         size_t                  hp_privsize;
  53         unsigned long           hp_flags;
  54
  55         int                     (*hp_accept)(struct handshake_req *req,
  56                                              struct genl_info *info, int fd);
  57         void                    (*hp_done)(struct handshake_req *req,
  58                                            unsigned int status,
  59                                            struct genl_info *info);
  60         void                    (*hp_destroy)(struct handshake_req *req);
  61 };
  62
  63 enum hp_flags_bits {
  64         HANDSHAKE_F_PROTO_NOTIFY,
  65 };
  66
  67 /* netlink.c */
  68 int handshake_genl_notify(struct net *net, const struct handshake_proto *proto,
  69                           gfp_t flags);
  70 struct nlmsghdr *handshake_genl_put(struct sk_buff *msg,
  71                                     struct genl_info *info);
  72 struct handshake_net *handshake_pernet(struct net *net);
  73
  74 /* request.c */
  75 struct handshake_req *handshake_req_alloc(const struct handshake_proto *proto,
  76                                           gfp_t flags);
  77 int handshake_req_hash_init(void);
  78 void handshake_req_hash_destroy(void);
  79 void *handshake_req_private(struct handshake_req *req);
  80 struct handshake_req *handshake_req_hash_lookup(struct sock *sk);
  81 struct handshake_req *handshake_req_next(struct handshake_net *hn, int class);
  82 int handshake_req_submit(struct socket *sock, struct handshake_req *req,
  83                          gfp_t flags);
  84 void handshake_complete(struct handshake_req *req, unsigned int status,
  85                         struct genl_info *info);
  86 bool handshake_req_cancel(struct sock *sk);
  87
  88 #endif /* _INTERNAL_HANDSHAKE_H */