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
 57static 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 */
 64struct 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 */
 83static inline void strp_pause(struct strparser *strp)
 84{
 85	strp->paused = 1;
 86}
 87
 88/* May be called without holding lock for attached socket */
 89void strp_unpause(struct strparser *strp);
 90/* Must be called with process lock held (lock_sock) */
 91void __strp_unpause(struct strparser *strp);
 92
 93static 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
117static 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
135void strp_done(struct strparser *strp);
136void strp_stop(struct strparser *strp);
137void strp_check_rcv(struct strparser *strp);
138int strp_init(struct strparser *strp, struct sock *sk,
139	      const struct strp_callbacks *cb);
140void strp_data_ready(struct strparser *strp);
141int 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_ */