1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Stream Parser
4 *
5 * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
6 */
7
8#ifndef __NET_STRPARSER_H_
9#define __NET_STRPARSER_H_
10
11#include <linux/skbuff.h>
12#include <net/sock.h>
13
14#define STRP_STATS_ADD(stat, count) ((stat) += (count))
15#define STRP_STATS_INCR(stat) ((stat)++)
16
17struct strp_stats {
18	unsigned long long msgs;
19	unsigned long long bytes;
20	unsigned int mem_fail;
21	unsigned int need_more_hdr;
22	unsigned int msg_too_big;
23	unsigned int msg_timeouts;
24	unsigned int bad_hdr_len;
25};
26
27struct strp_aggr_stats {
28	unsigned long long msgs;
29	unsigned long long bytes;
30	unsigned int mem_fail;
31	unsigned int need_more_hdr;
32	unsigned int msg_too_big;
33	unsigned int msg_timeouts;
34	unsigned int bad_hdr_len;
35	unsigned int aborts;
36	unsigned int interrupted;
37	unsigned int unrecov_intr;
38};
39
40struct strparser;
41
42/* Callbacks are called with lock held for the attached socket */
43struct strp_callbacks {
44	int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
45	void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
46	int (*read_sock_done)(struct strparser *strp, int err);
47	void (*abort_parser)(struct strparser *strp, int err);
48	void (*lock)(struct strparser *strp);
49	void (*unlock)(struct strparser *strp);
50};
51
52struct strp_msg {
53	int full_len;
54	int offset;
55};
56
57struct _strp_msg {
58	/* Internal cb structure. struct strp_msg must be first for passing
59	 * to upper layer.
60	 */
61	struct strp_msg strp;
62	int accum_len;
63};
64
65struct sk_skb_cb {
66#define SK_SKB_CB_PRIV_LEN 20
67	unsigned char data[SK_SKB_CB_PRIV_LEN];
68	struct _strp_msg strp;
69};
70
71static inline struct strp_msg *strp_msg(struct sk_buff *skb)
72{
73	return (struct strp_msg *)((void *)skb->cb +
74		offsetof(struct sk_skb_cb, strp));
75}
76
77/* Structure for an attached lower socket */
78struct strparser {
79	struct sock *sk;
80
81	u32 stopped : 1;
82	u32 paused : 1;
83	u32 aborted : 1;
84	u32 interrupted : 1;
85	u32 unrecov_intr : 1;
86
87	struct sk_buff **skb_nextp;
88	struct sk_buff *skb_head;
89	unsigned int need_bytes;
90	struct delayed_work msg_timer_work;
91	struct work_struct work;
92	struct strp_stats stats;
93	struct strp_callbacks cb;
94};
95
96/* Must be called with lock held for attached socket */
97static inline void strp_pause(struct strparser *strp)
98{
99	strp->paused = 1;
100}
101
102/* May be called without holding lock for attached socket */
103void strp_unpause(struct strparser *strp);
104/* Must be called with process lock held (lock_sock) */
105void __strp_unpause(struct strparser *strp);
106
107static inline void save_strp_stats(struct strparser *strp,
108				   struct strp_aggr_stats *agg_stats)
109{
110	/* Save psock statistics in the mux when psock is being unattached. */
111
112#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=		\
113				 strp->stats._stat)
114	SAVE_PSOCK_STATS(msgs);
115	SAVE_PSOCK_STATS(bytes);
116	SAVE_PSOCK_STATS(mem_fail);
117	SAVE_PSOCK_STATS(need_more_hdr);
118	SAVE_PSOCK_STATS(msg_too_big);
119	SAVE_PSOCK_STATS(msg_timeouts);
120	SAVE_PSOCK_STATS(bad_hdr_len);
121#undef SAVE_PSOCK_STATS
122
123	if (strp->aborted)
124		agg_stats->aborts++;
125	if (strp->interrupted)
126		agg_stats->interrupted++;
127	if (strp->unrecov_intr)
128		agg_stats->unrecov_intr++;
129}
130
131static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
132					struct strp_aggr_stats *agg_stats)
133{
134#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
135	SAVE_PSOCK_STATS(msgs);
136	SAVE_PSOCK_STATS(bytes);
137	SAVE_PSOCK_STATS(mem_fail);
138	SAVE_PSOCK_STATS(need_more_hdr);
139	SAVE_PSOCK_STATS(msg_too_big);
140	SAVE_PSOCK_STATS(msg_timeouts);
141	SAVE_PSOCK_STATS(bad_hdr_len);
142	SAVE_PSOCK_STATS(aborts);
143	SAVE_PSOCK_STATS(interrupted);
144	SAVE_PSOCK_STATS(unrecov_intr);
145#undef SAVE_PSOCK_STATS
146
147}
148
149void strp_done(struct strparser *strp);
150void strp_stop(struct strparser *strp);
151void strp_check_rcv(struct strparser *strp);
152int strp_init(struct strparser *strp, struct sock *sk,
153	      const struct strp_callbacks *cb);
154void strp_data_ready(struct strparser *strp);
155int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
156		 unsigned int orig_offset, size_t orig_len,
157		 size_t max_msg_size, long timeo);
158
159#endif /* __NET_STRPARSER_H_ */
160