/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

#ifndef _SOCKFS_SOCKFILTER_H
#define _SOCKFS_SOCKFILTER_H

#include <sys/kstat.h>
#include <sys/list.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockfilter.h>

#ifdef  __cplusplus
extern "C" {
#endif

struct sonode;
struct sockparams;

typedef struct sof_module       sof_module_t;
typedef struct sof_entry_kstat  sof_entry_kstat_t;
typedef struct sof_entry        sof_entry_t;
typedef struct sof_instance     sof_instance_t;
typedef struct sof_kstat        sof_kstat_t;

#define SOF_MAXNAMELEN          FILNAME_MAX
#define SOF_MAXSOCKTUPLECNT     32
#define SOF_MODPATH             SOCKMOD_PATH

struct sof_module {
        char            *sofm_name;
        sof_ops_t       sofm_ops;
        uint_t          sofm_refcnt;
        list_node_t     sofm_node;
};

struct sof_kstat {
        kstat_named_t   sofks_defer_closed;
        kstat_named_t   sofks_defer_close_backlog;
        kstat_named_t   sofks_defer_close_failed_backlog_too_big;
};

#define SOF_GLOBAL_STAT_BUMP(s) \
        atomic_inc_64(&sof_stat.sofks_##s.value.ui64)

/*
 * Per filter statistics.
 */
struct sof_entry_kstat {
        kstat_named_t   sofek_nactive;          /* # of consumers */
        kstat_named_t   sofek_tot_active_attach;
        kstat_named_t   sofek_tot_passive_attach;
        kstat_named_t   sofek_ndeferred;        /* # of deferred conns */
        kstat_named_t   sofek_attach_failures;
};

/*
 * Socket filter entry - one for each configured filter (added and
 * removed by soconfig(8)).
 *
 * sofe_flags, sofe_refcnt and sofe_mod are protected by sofe_lock, and all
 * other fields are write once.
 */
struct sof_entry {
        char            sofe_name[SOF_MAXNAMELEN];      /* filter name */
        char            sofe_modname[MODMAXNAMELEN];    /* filter module */
        sof_hint_t      sofe_hint;                      /* order hint */
        char            *sofe_hintarg;                  /* hint argument */
        list_node_t     sofe_node;                      /* global list node */
        uint_t          sofe_socktuple_cnt;             /* # of socket tuples */
        sof_socktuple_t *sofe_socktuple;                /* socket tuple list */

        sof_entry_kstat_t sofe_kstat;                   /* filter stats */
        kstat_t         *sofe_ksp;

        kmutex_t        sofe_lock;
        char            sofe_flags;                     /* SOFEF_* flags */
        uint_t          sofe_refcnt;                    /* # of instances */
        sof_module_t    *sofe_mod;                      /* filter module */
};

/* Filter entry flags */
#define SOFEF_AUTO      0x1     /* automatic filter */
#define SOFEF_PROG      0x2     /* programmatic filter */
#define SOFEF_CONDEMED  0x4     /* removed by soconfig(8) */

/*
 * Socket filter instance - one for each socket using a sof_entry_t
 */
struct sof_instance {
        sof_ops_t       *sofi_ops;      /* filter ops */
        void            *sofi_cookie;   /* filter cookie (from attach) */
        char            sofi_flags;     /* instance flags (SOFIF_*) */
        sof_instance_t  *sofi_prev;     /* up the stack */
        sof_instance_t  *sofi_next;     /* down the stack */
        struct sonode   *sofi_sonode;   /* socket instance is attached to */
        sof_entry_t     *sofi_filter;   /* filter this is an instance of */
};

/* Filter instance flags */
#define SOFIF_BYPASS            0x1     /* filter does not want any callbacks */
#define SOFIF_DEFER             0x2     /* defer notification of socket */
#define SOFIF_RCV_FLOWCTRL      0x4     /* flow control recv path */
#define SOFIF_SND_FLOWCTRL      0x8     /* flow control send path */

#define SOF_STAT_ADD(i, s, v) \
        atomic_add_64(&(i)->sofi_filter->sofe_kstat.sofek_##s.value.ui64, (v))

extern void     sof_init(void);

extern void     sof_entry_free(sof_entry_t *);
extern int      sof_entry_add(sof_entry_t *);
extern sof_entry_t *sof_entry_remove_by_name(const char *);
extern int      sof_entry_proc_sockparams(sof_entry_t *, struct sockparams *);

extern int      sof_sockparams_init(struct sockparams *);
extern void     sof_sockparams_fini(struct sockparams *);

extern int      sof_sonode_autoattach_filters(struct sonode *, cred_t *);
extern int      sof_sonode_inherit_filters(struct sonode *, struct sonode *);
extern void     sof_sonode_closing(struct sonode *);
extern void     sof_sonode_cleanup(struct sonode *);
extern void     sof_sonode_notify_filters(struct sonode *, sof_event_t,
    uintptr_t);
extern boolean_t sof_sonode_drop_deferred(struct sonode *);

extern int      sof_setsockopt(struct sonode *, int, const void *, socklen_t,
    struct cred *);
extern int      sof_getsockopt(struct sonode *, int, void *, socklen_t *,
    struct cred *);

extern int      sof_rval2errno(sof_rval_t);

#define SOF_INTERESTED(inst, op)                        \
        (!((inst)->sofi_flags & SOFIF_BYPASS) &&        \
        (inst)->sofi_ops->sofop_##op != NULL)

/*
 * SOF_FILTER_OP traverses the filter stack for sonode `so' top-down,
 * calling `op' for each filter with the supplied `args'. A non-negative
 * return value indicates that a filter action was taken.
 */
#define __SOF_FILTER_OP(so, op, cr, ...)                \
        sof_instance_t *__inst;                                 \
        sof_rval_t __rval;                                      \
                                                                \
        for (__inst = (so)->so_filter_top; __inst != NULL;      \
            __inst = __inst->sofi_next) {                       \
                if (!SOF_INTERESTED(__inst, op))                \
                        continue;                               \
                __rval = (__inst->sofi_ops->sofop_##op)((sof_handle_t)__inst,\
                    __inst->sofi_cookie, __VA_ARGS__, cr);      \
                DTRACE_PROBE2(filter__action, (sof_instance_t), __inst,\
                    (sof_rval_t), __rval);                      \
                if (__rval != SOF_RVAL_CONTINUE)                \
                        return (sof_rval2errno(__rval));        \
        }                                                       \
        return (-1);

extern mblk_t   *sof_filter_data_out_from(struct sonode *so,
    sof_instance_t *, mblk_t *, struct nmsghdr *, cred_t *, int *);
extern mblk_t   *sof_filter_data_in_proc(struct sonode *so,
    mblk_t *, mblk_t **);
extern int      sof_filter_bind(struct sonode *, struct sockaddr *,
    socklen_t *, cred_t *);
extern int      sof_filter_listen(struct sonode *, int *, cred_t *);
extern int      sof_filter_connect(struct sonode *, struct sockaddr *,
    socklen_t *, cred_t *);
extern int      sof_filter_accept(struct sonode *, cred_t *);
extern int      sof_filter_shutdown(struct sonode *, int *, cred_t *);
extern int      sof_filter_getsockname(struct sonode *, struct sockaddr *,
    socklen_t *, cred_t *);
extern int      sof_filter_getpeername(struct sonode *, struct sockaddr *,
    socklen_t *, cred_t *);
extern int      sof_filter_setsockopt(struct sonode *, int, int, void *,
    socklen_t *, cred_t *);
extern int      sof_filter_getsockopt(struct sonode *, int, int, void *,
    socklen_t *, cred_t *);
extern int      sof_filter_ioctl(struct sonode *, int, intptr_t, int,
    int32_t *, cred_t *);

#define SOF_FILTER_DATA_OUT(so, mp, msg, cr, errp) \
        sof_filter_data_out_from(so, (so)->so_filter_top, mp, msg, cr, errp)
#define SOF_FILTER_DATA_OUT_FROM(so, inst, mp, msg, cr, errp) \
        sof_filter_data_out_from(so, inst, mp, msg, cr, errp)

#ifdef  __cplusplus
}
#endif

#endif  /* _SOCKFS_SOCKFILTER_H */