1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* SCTP kernel implementation
3  * (C) Copyright IBM Corp. 2001, 2004
4  * Copyright (c) 1999-2000 Cisco, Inc.
5  * Copyright (c) 1999-2001 Motorola, Inc.
6  * Copyright (c) 2001 Intel Corp.
7  * Copyright (c) 2001 Nokia, Inc.
8  * Copyright (c) 2001 La Monte H.P. Yarroll
9  *
10  * These are the definitions needed for the sctp_ulpevent type.  The
11  * sctp_ulpevent type is used to carry information from the state machine
12  * upwards to the ULP.
13  *
14  * This file is part of the SCTP kernel implementation
15  *
16  * Please send any bug reports or fixes you make to the
17  * email address(es):
18  *    lksctp developers <linux-sctp@vger.kernel.org>
19  *
20  * Written or modified by:
21  *   Jon Grimm             <jgrimm@us.ibm.com>
22  *   La Monte H.P. Yarroll <piggy@acm.org>
23  *   Karl Knutson          <karl@athena.chicago.il.us>
24  *   Sridhar Samudrala     <sri@us.ibm.com>
25  */
26 
27 #ifndef __sctp_ulpevent_h__
28 #define __sctp_ulpevent_h__
29 
30 /* A structure to carry information to the ULP (e.g. Sockets API) */
31 /* Warning: This sits inside an skb.cb[] area.  Be very careful of
32  * growing this structure as it is at the maximum limit now.
33  *
34  * sctp_ulpevent is saved in sk->cb(48 bytes), whose last 4 bytes
35  * have been taken by sock_skb_cb, So here it has to use 'packed'
36  * to make sctp_ulpevent fit into the rest 44 bytes.
37  */
38 struct sctp_ulpevent {
39 	struct sctp_association *asoc;
40 	struct sctp_chunk *chunk;
41 	unsigned int rmem_len;
42 	union {
43 		__u32 mid;
44 		__u16 ssn;
45 	};
46 	union {
47 		__u32 ppid;
48 		__u32 fsn;
49 	};
50 	__u32 tsn;
51 	__u32 cumtsn;
52 	__u16 stream;
53 	__u16 flags;
54 	__u16 msg_flags;
55 } __packed;
56 
57 /* Retrieve the skb this event sits inside of. */
sctp_event2skb(const struct sctp_ulpevent * ev)58 static inline struct sk_buff *sctp_event2skb(const struct sctp_ulpevent *ev)
59 {
60 	return container_of((void *)ev, struct sk_buff, cb);
61 }
62 
63 /* Retrieve & cast the event sitting inside the skb. */
sctp_skb2event(struct sk_buff * skb)64 static inline struct sctp_ulpevent *sctp_skb2event(struct sk_buff *skb)
65 {
66 	return (struct sctp_ulpevent *)skb->cb;
67 }
68 
69 void sctp_ulpevent_free(struct sctp_ulpevent *);
70 int sctp_ulpevent_is_notification(const struct sctp_ulpevent *);
71 unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list);
72 
73 struct sctp_ulpevent *sctp_ulpevent_make_assoc_change(
74 	const struct sctp_association *asoc,
75 	__u16 flags,
76 	__u16 state,
77 	__u16 error,
78 	__u16 outbound,
79 	__u16 inbound,
80 	struct sctp_chunk *chunk,
81 	gfp_t gfp);
82 
83 struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
84 	const struct sctp_association *asoc,
85 	const struct sockaddr_storage *aaddr,
86 	int flags,
87 	int state,
88 	int error,
89 	gfp_t gfp);
90 
91 struct sctp_ulpevent *sctp_ulpevent_make_remote_error(
92 	const struct sctp_association *asoc,
93 	struct sctp_chunk *chunk,
94 	__u16 flags,
95 	gfp_t gfp);
96 struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
97 	const struct sctp_association *asoc,
98 	struct sctp_chunk *chunk,
99 	__u16 flags,
100 	__u32 error,
101 	gfp_t gfp);
102 
103 struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
104 	const struct sctp_association *asoc,
105 	__u16 flags,
106 	gfp_t gfp);
107 
108 struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
109 	const struct sctp_association *asoc,
110 	__u32 indication, __u32 sid, __u32 seq,
111 	__u32 flags, gfp_t gfp);
112 
113 struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
114 	const struct sctp_association *asoc, gfp_t gfp);
115 
116 struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
117 	struct sctp_chunk *chunk,
118 	gfp_t gfp);
119 
120 struct sctp_ulpevent *sctp_ulpevent_make_authkey(
121 	const struct sctp_association *asoc, __u16 key_id,
122 	__u32 indication, gfp_t gfp);
123 
124 struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
125 	const struct sctp_association *asoc, gfp_t gfp);
126 
127 struct sctp_ulpevent *sctp_ulpevent_make_stream_reset_event(
128 	const struct sctp_association *asoc, __u16 flags,
129 	__u16 stream_num, __be16 *stream_list, gfp_t gfp);
130 
131 struct sctp_ulpevent *sctp_ulpevent_make_assoc_reset_event(
132 	const struct sctp_association *asoc, __u16 flags,
133 	 __u32 local_tsn, __u32 remote_tsn, gfp_t gfp);
134 
135 struct sctp_ulpevent *sctp_ulpevent_make_stream_change_event(
136 	const struct sctp_association *asoc, __u16 flags,
137 	__u32 strchange_instrms, __u32 strchange_outstrms, gfp_t gfp);
138 
139 struct sctp_ulpevent *sctp_make_reassembled_event(
140 	struct net *net, struct sk_buff_head *queue,
141 	struct sk_buff *f_frag, struct sk_buff *l_frag);
142 
143 void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
144 				   struct msghdr *);
145 void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
146 				struct msghdr *);
147 void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
148 				struct msghdr *, struct sock *sk);
149 
150 __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event);
151 
sctp_ulpevent_type_set(__u16 * subscribe,__u16 sn_type,__u8 on)152 static inline void sctp_ulpevent_type_set(__u16 *subscribe,
153 					  __u16 sn_type, __u8 on)
154 {
155 	if (sn_type > SCTP_SN_TYPE_MAX)
156 		return;
157 
158 	if (on)
159 		*subscribe |=  (1 << (sn_type - SCTP_SN_TYPE_BASE));
160 	else
161 		*subscribe &= ~(1 << (sn_type - SCTP_SN_TYPE_BASE));
162 }
163 
164 /* Is this event type enabled? */
sctp_ulpevent_type_enabled(__u16 subscribe,__u16 sn_type)165 static inline bool sctp_ulpevent_type_enabled(__u16 subscribe, __u16 sn_type)
166 {
167 	if (sn_type > SCTP_SN_TYPE_MAX)
168 		return false;
169 
170 	return subscribe & (1 << (sn_type - SCTP_SN_TYPE_BASE));
171 }
172 
173 /* Given an event subscription, is this event enabled? */
sctp_ulpevent_is_enabled(const struct sctp_ulpevent * event,__u16 subscribe)174 static inline bool sctp_ulpevent_is_enabled(const struct sctp_ulpevent *event,
175 					    __u16 subscribe)
176 {
177 	__u16 sn_type;
178 
179 	if (!sctp_ulpevent_is_notification(event))
180 		return true;
181 
182 	sn_type = sctp_ulpevent_get_notification_type(event);
183 
184 	return sctp_ulpevent_type_enabled(subscribe, sn_type);
185 }
186 
187 #endif /* __sctp_ulpevent_h__ */
188