xref: /linux/include/net/strparser.h (revision ef815d2cba782e96b9aad9483523d474ed41c62a)
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 struct _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 
65 struct sk_skb_cb {
66 #define SK_SKB_CB_PRIV_LEN 20
67 	unsigned char data[SK_SKB_CB_PRIV_LEN];
68 	/* align strp on cache line boundary within skb->cb[] */
69 	unsigned char pad[4];
70 	struct _strp_msg strp;
71 
72 	/* strp users' data follows */
73 	struct tls_msg {
74 		u8 control;
75 	} tls;
76 	/* temp_reg is a temporary register used for bpf_convert_data_end_access
77 	 * when dst_reg == src_reg.
78 	 */
79 	u64 temp_reg;
80 };
81 
82 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
83 {
84 	return (struct strp_msg *)((void *)skb->cb +
85 		offsetof(struct sk_skb_cb, strp));
86 }
87 
88 /* Structure for an attached lower socket */
89 struct strparser {
90 	struct sock *sk;
91 
92 	u32 stopped : 1;
93 	u32 paused : 1;
94 	u32 aborted : 1;
95 	u32 interrupted : 1;
96 	u32 unrecov_intr : 1;
97 
98 	struct sk_buff **skb_nextp;
99 	struct sk_buff *skb_head;
100 	unsigned int need_bytes;
101 	struct delayed_work msg_timer_work;
102 	struct work_struct work;
103 	struct strp_stats stats;
104 	struct strp_callbacks cb;
105 };
106 
107 /* Must be called with lock held for attached socket */
108 static inline void strp_pause(struct strparser *strp)
109 {
110 	strp->paused = 1;
111 }
112 
113 /* May be called without holding lock for attached socket */
114 void strp_unpause(struct strparser *strp);
115 /* Must be called with process lock held (lock_sock) */
116 void __strp_unpause(struct strparser *strp);
117 
118 static inline void save_strp_stats(struct strparser *strp,
119 				   struct strp_aggr_stats *agg_stats)
120 {
121 	/* Save psock statistics in the mux when psock is being unattached. */
122 
123 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=		\
124 				 strp->stats._stat)
125 	SAVE_PSOCK_STATS(msgs);
126 	SAVE_PSOCK_STATS(bytes);
127 	SAVE_PSOCK_STATS(mem_fail);
128 	SAVE_PSOCK_STATS(need_more_hdr);
129 	SAVE_PSOCK_STATS(msg_too_big);
130 	SAVE_PSOCK_STATS(msg_timeouts);
131 	SAVE_PSOCK_STATS(bad_hdr_len);
132 #undef SAVE_PSOCK_STATS
133 
134 	if (strp->aborted)
135 		agg_stats->aborts++;
136 	if (strp->interrupted)
137 		agg_stats->interrupted++;
138 	if (strp->unrecov_intr)
139 		agg_stats->unrecov_intr++;
140 }
141 
142 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
143 					struct strp_aggr_stats *agg_stats)
144 {
145 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
146 	SAVE_PSOCK_STATS(msgs);
147 	SAVE_PSOCK_STATS(bytes);
148 	SAVE_PSOCK_STATS(mem_fail);
149 	SAVE_PSOCK_STATS(need_more_hdr);
150 	SAVE_PSOCK_STATS(msg_too_big);
151 	SAVE_PSOCK_STATS(msg_timeouts);
152 	SAVE_PSOCK_STATS(bad_hdr_len);
153 	SAVE_PSOCK_STATS(aborts);
154 	SAVE_PSOCK_STATS(interrupted);
155 	SAVE_PSOCK_STATS(unrecov_intr);
156 #undef SAVE_PSOCK_STATS
157 
158 }
159 
160 void strp_done(struct strparser *strp);
161 void strp_stop(struct strparser *strp);
162 void strp_check_rcv(struct strparser *strp);
163 int strp_init(struct strparser *strp, struct sock *sk,
164 	      const struct strp_callbacks *cb);
165 void strp_data_ready(struct strparser *strp);
166 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
167 		 unsigned int orig_offset, size_t orig_len,
168 		 size_t max_msg_size, long timeo);
169 
170 #endif /* __NET_STRPARSER_H_ */
171