include/net/strparser.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  * Stream Parser
0004  *
0005  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
0006  */
0007
0008 #ifndef __NET_STRPARSER_H_
0009 #define __NET_STRPARSER_H_
0010
0011 #include <linux/skbuff.h>
0012 #include <net/sock.h>
0013
0014 #define STRP_STATS_ADD(stat, count) ((stat) += (count))
0015 #define STRP_STATS_INCR(stat) ((stat)++)
0016
0017 struct strp_stats {
0018     unsigned long long msgs;
0019     unsigned long long bytes;
0020     unsigned int mem_fail;
0021     unsigned int need_more_hdr;
0022     unsigned int msg_too_big;
0023     unsigned int msg_timeouts;
0024     unsigned int bad_hdr_len;
0025 };
0026
0027 struct strp_aggr_stats {
0028     unsigned long long msgs;
0029     unsigned long long bytes;
0030     unsigned int mem_fail;
0031     unsigned int need_more_hdr;
0032     unsigned int msg_too_big;
0033     unsigned int msg_timeouts;
0034     unsigned int bad_hdr_len;
0035     unsigned int aborts;
0036     unsigned int interrupted;
0037     unsigned int unrecov_intr;
0038 };
0039
0040 struct strparser;
0041
0042 /* Callbacks are called with lock held for the attached socket */
0043 struct strp_callbacks {
0044     int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
0045     void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
0046     int (*read_sock_done)(struct strparser *strp, int err);
0047     void (*abort_parser)(struct strparser *strp, int err);
0048     void (*lock)(struct strparser *strp);
0049     void (*unlock)(struct strparser *strp);
0050 };
0051
0052 struct strp_msg {
0053     int full_len;
0054     int offset;
0055 };
0056
0057 struct _strp_msg {
0058     /* Internal cb structure. struct strp_msg must be first for passing
0059      * to upper layer.
0060      */
0061     struct strp_msg strp;
0062     int accum_len;
0063 };
0064
0065 struct sk_skb_cb {
0066 #define SK_SKB_CB_PRIV_LEN 20
0067     unsigned char data[SK_SKB_CB_PRIV_LEN];
0068     /* align strp on cache line boundary within skb->cb[] */
0069     unsigned char pad[4];
0070     struct _strp_msg strp;
0071
0072     /* strp users' data follows */
0073     struct tls_msg {
0074         u8 control;
0075     } tls;
0076     /* temp_reg is a temporary register used for bpf_convert_data_end_access
0077      * when dst_reg == src_reg.
0078      */
0079     u64 temp_reg;
0080 };
0081
0082 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
0083 {
0084     return (struct strp_msg *)((void *)skb->cb +
0085         offsetof(struct sk_skb_cb, strp));
0086 }
0087
0088 /* Structure for an attached lower socket */
0089 struct strparser {
0090     struct sock *sk;
0091
0092     u32 stopped : 1;
0093     u32 paused : 1;
0094     u32 aborted : 1;
0095     u32 interrupted : 1;
0096     u32 unrecov_intr : 1;
0097
0098     struct sk_buff **skb_nextp;
0099     struct sk_buff *skb_head;
0100     unsigned int need_bytes;
0101     struct delayed_work msg_timer_work;
0102     struct work_struct work;
0103     struct strp_stats stats;
0104     struct strp_callbacks cb;
0105 };
0106
0107 /* Must be called with lock held for attached socket */
0108 static inline void strp_pause(struct strparser *strp)
0109 {
0110     strp->paused = 1;
0111 }
0112
0113 /* May be called without holding lock for attached socket */
0114 void strp_unpause(struct strparser *strp);
0115 /* Must be called with process lock held (lock_sock) */
0116 void __strp_unpause(struct strparser *strp);
0117
0118 static inline void save_strp_stats(struct strparser *strp,
0119                    struct strp_aggr_stats *agg_stats)
0120 {
0121     /* Save psock statistics in the mux when psock is being unattached. */
0122
0123 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=        \
0124                  strp->stats._stat)
0125     SAVE_PSOCK_STATS(msgs);
0126     SAVE_PSOCK_STATS(bytes);
0127     SAVE_PSOCK_STATS(mem_fail);
0128     SAVE_PSOCK_STATS(need_more_hdr);
0129     SAVE_PSOCK_STATS(msg_too_big);
0130     SAVE_PSOCK_STATS(msg_timeouts);
0131     SAVE_PSOCK_STATS(bad_hdr_len);
0132 #undef SAVE_PSOCK_STATS
0133
0134     if (strp->aborted)
0135         agg_stats->aborts++;
0136     if (strp->interrupted)
0137         agg_stats->interrupted++;
0138     if (strp->unrecov_intr)
0139         agg_stats->unrecov_intr++;
0140 }
0141
0142 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
0143                     struct strp_aggr_stats *agg_stats)
0144 {
0145 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
0146     SAVE_PSOCK_STATS(msgs);
0147     SAVE_PSOCK_STATS(bytes);
0148     SAVE_PSOCK_STATS(mem_fail);
0149     SAVE_PSOCK_STATS(need_more_hdr);
0150     SAVE_PSOCK_STATS(msg_too_big);
0151     SAVE_PSOCK_STATS(msg_timeouts);
0152     SAVE_PSOCK_STATS(bad_hdr_len);
0153     SAVE_PSOCK_STATS(aborts);
0154     SAVE_PSOCK_STATS(interrupted);
0155     SAVE_PSOCK_STATS(unrecov_intr);
0156 #undef SAVE_PSOCK_STATS
0157
0158 }
0159
0160 void strp_done(struct strparser *strp);
0161 void strp_stop(struct strparser *strp);
0162 void strp_check_rcv(struct strparser *strp);
0163 int strp_init(struct strparser *strp, struct sock *sk,
0164           const struct strp_callbacks *cb);
0165 void strp_data_ready(struct strparser *strp);
0166 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
0167          unsigned int orig_offset, size_t orig_len,
0168          size_t max_msg_size, long timeo);
0169
0170 #endif /* __NET_STRPARSER_H_ */