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  
strp_msg(struct sk_buff * skb)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 */
strp_pause(struct strparser * strp)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  
save_strp_stats(struct strparser * strp,struct strp_aggr_stats * agg_stats)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  
aggregate_strp_stats(struct strp_aggr_stats * stats,struct strp_aggr_stats * agg_stats)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