xref: /openbmc/linux/include/net/strparser.h (revision d37cf9b63113f13d742713881ce691fc615d8b3b)
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)(struct strparser *strp, read_descriptor_t *desc,
47 			 sk_read_actor_t recv_actor);
48 	int (*read_sock_done)(struct strparser *strp, int err);
49 	void (*abort_parser)(struct strparser *strp, int err);
50 	void (*lock)(struct strparser *strp);
51 	void (*unlock)(struct strparser *strp);
52 };
53 
54 struct strp_msg {
55 	int full_len;
56 	int offset;
57 };
58 
59 struct _strp_msg {
60 	/* Internal cb structure. struct strp_msg must be first for passing
61 	 * to upper layer.
62 	 */
63 	struct strp_msg strp;
64 	int accum_len;
65 };
66 
67 struct sk_skb_cb {
68 #define SK_SKB_CB_PRIV_LEN 20
69 	unsigned char data[SK_SKB_CB_PRIV_LEN];
70 	/* align strp on cache line boundary within skb->cb[] */
71 	unsigned char pad[4];
72 	struct _strp_msg strp;
73 
74 	/* strp users' data follows */
75 	struct tls_msg {
76 		u8 control;
77 	} tls;
78 	/* temp_reg is a temporary register used for bpf_convert_data_end_access
79 	 * when dst_reg == src_reg.
80 	 */
81 	u64 temp_reg;
82 };
83 
strp_msg(struct sk_buff * skb)84 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
85 {
86 	return (struct strp_msg *)((void *)skb->cb +
87 		offsetof(struct sk_skb_cb, strp));
88 }
89 
90 /* Structure for an attached lower socket */
91 struct strparser {
92 	struct sock *sk;
93 
94 	u32 stopped : 1;
95 	u32 paused : 1;
96 	u32 aborted : 1;
97 	u32 interrupted : 1;
98 	u32 unrecov_intr : 1;
99 
100 	struct sk_buff **skb_nextp;
101 	struct sk_buff *skb_head;
102 	unsigned int need_bytes;
103 	struct delayed_work msg_timer_work;
104 	struct work_struct work;
105 	struct strp_stats stats;
106 	struct strp_callbacks cb;
107 };
108 
109 /* Must be called with lock held for attached socket */
strp_pause(struct strparser * strp)110 static inline void strp_pause(struct strparser *strp)
111 {
112 	strp->paused = 1;
113 }
114 
115 /* May be called without holding lock for attached socket */
116 void strp_unpause(struct strparser *strp);
117 /* Must be called with process lock held (lock_sock) */
118 void __strp_unpause(struct strparser *strp);
119 
save_strp_stats(struct strparser * strp,struct strp_aggr_stats * agg_stats)120 static inline void save_strp_stats(struct strparser *strp,
121 				   struct strp_aggr_stats *agg_stats)
122 {
123 	/* Save psock statistics in the mux when psock is being unattached. */
124 
125 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=		\
126 				 strp->stats._stat)
127 	SAVE_PSOCK_STATS(msgs);
128 	SAVE_PSOCK_STATS(bytes);
129 	SAVE_PSOCK_STATS(mem_fail);
130 	SAVE_PSOCK_STATS(need_more_hdr);
131 	SAVE_PSOCK_STATS(msg_too_big);
132 	SAVE_PSOCK_STATS(msg_timeouts);
133 	SAVE_PSOCK_STATS(bad_hdr_len);
134 #undef SAVE_PSOCK_STATS
135 
136 	if (strp->aborted)
137 		agg_stats->aborts++;
138 	if (strp->interrupted)
139 		agg_stats->interrupted++;
140 	if (strp->unrecov_intr)
141 		agg_stats->unrecov_intr++;
142 }
143 
aggregate_strp_stats(struct strp_aggr_stats * stats,struct strp_aggr_stats * agg_stats)144 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
145 					struct strp_aggr_stats *agg_stats)
146 {
147 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
148 	SAVE_PSOCK_STATS(msgs);
149 	SAVE_PSOCK_STATS(bytes);
150 	SAVE_PSOCK_STATS(mem_fail);
151 	SAVE_PSOCK_STATS(need_more_hdr);
152 	SAVE_PSOCK_STATS(msg_too_big);
153 	SAVE_PSOCK_STATS(msg_timeouts);
154 	SAVE_PSOCK_STATS(bad_hdr_len);
155 	SAVE_PSOCK_STATS(aborts);
156 	SAVE_PSOCK_STATS(interrupted);
157 	SAVE_PSOCK_STATS(unrecov_intr);
158 #undef SAVE_PSOCK_STATS
159 
160 }
161 
162 void strp_done(struct strparser *strp);
163 void strp_stop(struct strparser *strp);
164 void strp_check_rcv(struct strparser *strp);
165 int strp_init(struct strparser *strp, struct sock *sk,
166 	      const struct strp_callbacks *cb);
167 void strp_data_ready(struct strparser *strp);
168 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
169 		 unsigned int orig_offset, size_t orig_len,
170 		 size_t max_msg_size, long timeo);
171 
172 #endif /* __NET_STRPARSER_H_ */
173