include/net/strparser.h

   1 /*
   2  * Stream Parser
   3  *
   4  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2
   8  * as published by the Free Software Foundation.
   9  */
  10
  11 #ifndef __NET_STRPARSER_H_
  12 #define __NET_STRPARSER_H_
  13
  14 #include <linux/skbuff.h>
  15 #include <net/sock.h>
  16
  17 #define STRP_STATS_ADD(stat, count) ((stat) += (count))
  18 #define STRP_STATS_INCR(stat) ((stat)++)
  19
  20 struct strp_stats {
  21         unsigned long long msgs;
  22         unsigned long long bytes;
  23         unsigned int mem_fail;
  24         unsigned int need_more_hdr;
  25         unsigned int msg_too_big;
  26         unsigned int msg_timeouts;
  27         unsigned int bad_hdr_len;
  28 };
  29
  30 struct strp_aggr_stats {
  31         unsigned long long msgs;
  32         unsigned long long bytes;
  33         unsigned int mem_fail;
  34         unsigned int need_more_hdr;
  35         unsigned int msg_too_big;
  36         unsigned int msg_timeouts;
  37         unsigned int bad_hdr_len;
  38         unsigned int aborts;
  39         unsigned int interrupted;
  40         unsigned int unrecov_intr;
  41 };
  42
  43 struct strparser;
  44
  45 /* Callbacks are called with lock held for the attached socket */
  46 struct strp_callbacks {
  47         int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
  48         void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
  49         int (*read_sock_done)(struct strparser *strp, int err);
  50         void (*abort_parser)(struct strparser *strp, int err);
  51         void (*lock)(struct strparser *strp);
  52         void (*unlock)(struct strparser *strp);
  53 };
  54
  55 struct strp_msg {
  56         int full_len;
  57         int offset;
  58 };
  59
  60 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
  61 {
  62         return (struct strp_msg *)((void *)skb->cb +
  63                 offsetof(struct qdisc_skb_cb, data));
  64 }
  65
  66 /* Structure for an attached lower socket */
  67 struct strparser {
  68         struct sock *sk;
  69
  70         u32 stopped : 1;
  71         u32 paused : 1;
  72         u32 aborted : 1;
  73         u32 interrupted : 1;
  74         u32 unrecov_intr : 1;
  75
  76         struct sk_buff **skb_nextp;
  77         struct sk_buff *skb_head;
  78         unsigned int need_bytes;
  79         struct delayed_work msg_timer_work;
  80         struct work_struct work;
  81         struct strp_stats stats;
  82         struct strp_callbacks cb;
  83 };
  84
  85 /* Must be called with lock held for attached socket */
  86 static inline void strp_pause(struct strparser *strp)
  87 {
  88         strp->paused = 1;
  89 }
  90
  91 /* May be called without holding lock for attached socket */
  92 void strp_unpause(struct strparser *strp);
  93 /* Must be called with process lock held (lock_sock) */
  94 void __strp_unpause(struct strparser *strp);
  95
  96 static inline void save_strp_stats(struct strparser *strp,
  97                                    struct strp_aggr_stats *agg_stats)
  98 {
  99         /* Save psock statistics in the mux when psock is being unattached. */
 100
 101 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=            \
 102                                  strp->stats._stat)
 103         SAVE_PSOCK_STATS(msgs);
 104         SAVE_PSOCK_STATS(bytes);
 105         SAVE_PSOCK_STATS(mem_fail);
 106         SAVE_PSOCK_STATS(need_more_hdr);
 107         SAVE_PSOCK_STATS(msg_too_big);
 108         SAVE_PSOCK_STATS(msg_timeouts);
 109         SAVE_PSOCK_STATS(bad_hdr_len);
 110 #undef SAVE_PSOCK_STATS
 111
 112         if (strp->aborted)
 113                 agg_stats->aborts++;
 114         if (strp->interrupted)
 115                 agg_stats->interrupted++;
 116         if (strp->unrecov_intr)
 117                 agg_stats->unrecov_intr++;
 118 }
 119
 120 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
 121                                         struct strp_aggr_stats *agg_stats)
 122 {
 123 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
 124         SAVE_PSOCK_STATS(msgs);
 125         SAVE_PSOCK_STATS(bytes);
 126         SAVE_PSOCK_STATS(mem_fail);
 127         SAVE_PSOCK_STATS(need_more_hdr);
 128         SAVE_PSOCK_STATS(msg_too_big);
 129         SAVE_PSOCK_STATS(msg_timeouts);
 130         SAVE_PSOCK_STATS(bad_hdr_len);
 131         SAVE_PSOCK_STATS(aborts);
 132         SAVE_PSOCK_STATS(interrupted);
 133         SAVE_PSOCK_STATS(unrecov_intr);
 134 #undef SAVE_PSOCK_STATS
 135
 136 }
 137
 138 void strp_done(struct strparser *strp);
 139 void strp_stop(struct strparser *strp);
 140 void strp_check_rcv(struct strparser *strp);
 141 int strp_init(struct strparser *strp, struct sock *sk,
 142               const struct strp_callbacks *cb);
 143 void strp_data_ready(struct strparser *strp);
 144 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
 145                  unsigned int orig_offset, size_t orig_len,
 146                  size_t max_msg_size, long timeo);
 147
 148 #endif /* __NET_STRPARSER_H_ */