xref: /linux/include/net/strparser.h (revision be58f7103700a68d5c7ca60a2bc0b309907599ab)
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 
17 struct 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 
27 struct 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 
40 struct strparser;
41 
42 /* Callbacks are called with lock held for the attached socket */
43 struct 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 
52 struct strp_msg {
53 	int full_len;
54 	int offset;
55 };
56 
57 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
58 {
59 	return (struct strp_msg *)((void *)skb->cb +
60 		offsetof(struct qdisc_skb_cb, data));
61 }
62 
63 /* Structure for an attached lower socket */
64 struct strparser {
65 	struct sock *sk;
66 
67 	u32 stopped : 1;
68 	u32 paused : 1;
69 	u32 aborted : 1;
70 	u32 interrupted : 1;
71 	u32 unrecov_intr : 1;
72 
73 	struct sk_buff **skb_nextp;
74 	struct sk_buff *skb_head;
75 	unsigned int need_bytes;
76 	struct delayed_work msg_timer_work;
77 	struct work_struct work;
78 	struct strp_stats stats;
79 	struct strp_callbacks cb;
80 };
81 
82 /* Must be called with lock held for attached socket */
83 static inline void strp_pause(struct strparser *strp)
84 {
85 	strp->paused = 1;
86 }
87 
88 /* May be called without holding lock for attached socket */
89 void strp_unpause(struct strparser *strp);
90 /* Must be called with process lock held (lock_sock) */
91 void __strp_unpause(struct strparser *strp);
92 
93 static inline void save_strp_stats(struct strparser *strp,
94 				   struct strp_aggr_stats *agg_stats)
95 {
96 	/* Save psock statistics in the mux when psock is being unattached. */
97 
98 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=		\
99 				 strp->stats._stat)
100 	SAVE_PSOCK_STATS(msgs);
101 	SAVE_PSOCK_STATS(bytes);
102 	SAVE_PSOCK_STATS(mem_fail);
103 	SAVE_PSOCK_STATS(need_more_hdr);
104 	SAVE_PSOCK_STATS(msg_too_big);
105 	SAVE_PSOCK_STATS(msg_timeouts);
106 	SAVE_PSOCK_STATS(bad_hdr_len);
107 #undef SAVE_PSOCK_STATS
108 
109 	if (strp->aborted)
110 		agg_stats->aborts++;
111 	if (strp->interrupted)
112 		agg_stats->interrupted++;
113 	if (strp->unrecov_intr)
114 		agg_stats->unrecov_intr++;
115 }
116 
117 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
118 					struct strp_aggr_stats *agg_stats)
119 {
120 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
121 	SAVE_PSOCK_STATS(msgs);
122 	SAVE_PSOCK_STATS(bytes);
123 	SAVE_PSOCK_STATS(mem_fail);
124 	SAVE_PSOCK_STATS(need_more_hdr);
125 	SAVE_PSOCK_STATS(msg_too_big);
126 	SAVE_PSOCK_STATS(msg_timeouts);
127 	SAVE_PSOCK_STATS(bad_hdr_len);
128 	SAVE_PSOCK_STATS(aborts);
129 	SAVE_PSOCK_STATS(interrupted);
130 	SAVE_PSOCK_STATS(unrecov_intr);
131 #undef SAVE_PSOCK_STATS
132 
133 }
134 
135 void strp_done(struct strparser *strp);
136 void strp_stop(struct strparser *strp);
137 void strp_check_rcv(struct strparser *strp);
138 int strp_init(struct strparser *strp, struct sock *sk,
139 	      const struct strp_callbacks *cb);
140 void strp_data_ready(struct strparser *strp);
141 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
142 		 unsigned int orig_offset, size_t orig_len,
143 		 size_t max_msg_size, long timeo);
144 
145 #endif /* __NET_STRPARSER_H_ */
146