/*
 * 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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/systm.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/modctl.h>
#include <sys/sunddi.h>
#include <ipp/ipp.h>
#include <ipp/ipp_config.h>
#include <ipp/ipgpc/classifier.h>
#include <inet/ip.h>
#include <net/if.h>
#include <inet/ip_if.h>
#include <inet/ipp_common.h>

/* DDI file for ipgpc ipp module */

/* protects against multiple configs  */
static kmutex_t ipgpc_config_lock;

static int ipgpc_create_action(ipp_action_id_t, nvlist_t **, ipp_flags_t);
static int ipgpc_modify_action(ipp_action_id_t, nvlist_t **, ipp_flags_t);
static int ipgpc_destroy_action(ipp_action_id_t, ipp_flags_t);
static int ipgpc_info(ipp_action_id_t aid, int (*)(nvlist_t *, void *), void *,
    ipp_flags_t);
static int ipgpc_invoke_action(ipp_action_id_t, ipp_packet_t *);

ipp_ops_t ipgpc_ops = {
        IPPO_REV,
        ipgpc_create_action,    /* ippo_action_create */
        ipgpc_modify_action,    /* ippo_action_modify */
        ipgpc_destroy_action,   /* ippo_action_destroy */
        ipgpc_info,             /* ippo_action_info */
        ipgpc_invoke_action     /* ippo_action_invoke */
};

extern struct mod_ops mod_ippops;

/*
 * Module linkage information for the kernel.
 */
static struct modlipp modlipp = {
        &mod_ippops,
        "IP Generic Packet Classifier (ipgpc) module 1.0",
        &ipgpc_ops
};

static struct modlinkage modlinkage = {
        MODREV_1,
        (void *)&modlipp,
        NULL
};

#define __FN__  "_init"
int
_init(
        void)
{
        int rc;

        if (ipgpc_action_exist) {
                return (EBUSY);
        }
        /* init mutexes */
        mutex_init(&ipgpc_config_lock, NULL, MUTEX_DRIVER, NULL);
        mutex_init(&ipgpc_fid_list_lock, NULL, MUTEX_DRIVER, NULL);
        mutex_init(&ipgpc_cid_list_lock, NULL, MUTEX_DRIVER, NULL);
        mutex_init(&ipgpc_table_list_lock, NULL, MUTEX_DRIVER, NULL);
        mutex_init(&ipgpc_ds_table_id.lock, NULL, MUTEX_DRIVER, NULL);

        if ((rc = mod_install(&modlinkage)) != 0) {
                /* clean up after fail */
                mutex_destroy(&ipgpc_config_lock);
                mutex_destroy(&ipgpc_fid_list_lock);
                mutex_destroy(&ipgpc_cid_list_lock);
                mutex_destroy(&ipgpc_table_list_lock);
                mutex_destroy(&ipgpc_ds_table_id.lock);
        }

        return (rc);
}
#undef  __FN__

#define __FN__  "_fini"
int
_fini(
        void)
{
        int rc;

        if (ipgpc_action_exist) {
                return (EBUSY);
        }

        if ((rc = mod_remove(&modlinkage)) != 0) {
                return (rc);
        }
        /* destroy mutexes */
        mutex_destroy(&ipgpc_config_lock);
        mutex_destroy(&ipgpc_fid_list_lock);
        mutex_destroy(&ipgpc_cid_list_lock);
        mutex_destroy(&ipgpc_table_list_lock);
        mutex_destroy(&ipgpc_ds_table_id.lock);
        return (rc);
}
#undef  __FN__

#define __FN__  "_info"
int
_info(
        struct  modinfo *modinfop)
{
        return (mod_info(&modlinkage, modinfop));
}
#undef  __FN__

/*
 * ipgpc_create_action(aid, nvlpp, flags)
 *
 * creates a single instance of ipgpc, if one does not exist.  If an action
 * instance already exists, fail with EBUSY
 *
 * if nvlpp contains the name IPP_ACTION_STATS_ENABLE, then process it and
 * determine if global stats should be collected
 *
 * the ipgpc_config_lock is taken to block out any other creates or destroys
 * the are issued while the create is taking place
 */
/* ARGSUSED */
static int
ipgpc_create_action(ipp_action_id_t aid, nvlist_t **nvlpp, ipp_flags_t flags)
{
        int rc;
        uint32_t stat;
        nvlist_t *nvlp;

        nvlp = *nvlpp;
        *nvlpp = NULL;          /* nvlist should be NULL when this returns */

        /* only one ipgpc action instance can be loaded at once */
        if (ipgpc_action_exist) {
                nvlist_free(nvlp);
                return (EBUSY);
        } else {
                mutex_enter(&ipgpc_config_lock);
                if (ipgpc_action_exist) {
                        nvlist_free(nvlp);
                        mutex_exit(&ipgpc_config_lock);
                        return (EBUSY);
                }
                /* check for action param IPP_ACTION_STATS_ENABLE */
                if ((rc = nvlist_lookup_uint32(nvlp, IPP_ACTION_STATS_ENABLE,
                    &stat)) != 0) {
                        ipgpc_gather_stats = B_FALSE; /* disabled by default */
                } else {
                        ipgpc_gather_stats = (boolean_t)stat;
                }
                if ((rc = ipgpc_initialize(aid)) != 0) {
                        ipgpc0dbg(("ipgpc_create_action: ipgpc_intialize " \
                            "error %d", rc));
                        ipgpc_destroy(IPP_DESTROY_REF);
                        ipgpc_action_exist = B_FALSE;
                        nvlist_free(nvlp);
                        mutex_exit(&ipgpc_config_lock);
                        return (rc);
                }
                ipgpc_action_exist = B_TRUE;
                nvlist_free(nvlp);
                mutex_exit(&ipgpc_config_lock);
                return (0);
        }
}

/*
 * ipgpc_modify_action
 *
 * modify an instance of ipgpc
 *
 * nvlpp will contain the configuration type to switch off of.  Use this
 * to determine what modification should be made.  If the modification fails,
 * return the appropriate error.
 */
/* ARGSUSED */
static int
ipgpc_modify_action(ipp_action_id_t aid, nvlist_t **nvlpp, ipp_flags_t flags)
{
        nvlist_t *nvlp;
        int rc = 0;
        uint8_t config_type;
        uint32_t stat;
        char *name;
        int32_t filter_instance;
        ipgpc_filter_t *filter;
        ipgpc_class_t *aclass;

        nvlp = *nvlpp;
        *nvlpp = NULL;          /* nvlist should be NULL when this returns */

        if ((rc = nvlist_lookup_byte(nvlp, IPP_CONFIG_TYPE, &config_type))
            != 0) {
                nvlist_free(nvlp);
                ipgpc0dbg(("ipgpc_modify_action: invalid configuration type"));
                return (EINVAL);
        }

        switch (config_type) {
        case IPP_SET:           /* set an action parameter */
                if ((rc = nvlist_lookup_uint32(nvlp, IPP_ACTION_STATS_ENABLE,
                    &stat)) != 0) {
                        nvlist_free(nvlp);
                        ipgpc0dbg(("ipgpc_modify_action: invalid IPP_SET " \
                            "parameter"));
                        return (EINVAL);
                } else {
                        ipgpc_gather_stats = (boolean_t)stat;
                }
                break;
        case CLASSIFIER_ADD_FILTER: /* add a filter */
                filter = kmem_zalloc(sizeof (ipgpc_filter_t), KM_SLEEP);
                if ((rc = ipgpc_parse_filter(filter, nvlp)) != 0) {
                        ipgpc0dbg(("ipgpc_modify_action: invalid filter"));
                        ipgpc_filter_destructor(filter);
                        kmem_free(filter, sizeof (ipgpc_filter_t));
                        break;
                }
                /* parse class name */
                if ((rc = nvlist_lookup_string(nvlp, CLASSIFIER_CLASS_NAME,
                    &name)) != 0) {
                        ipgpc0dbg(("ipgpc_modify_action: class name missing"));
                        ipgpc_filter_destructor(filter);
                        kmem_free(filter, sizeof (ipgpc_filter_t));
                        break;
                }
                rc = ipgpc_addfilter(filter, name, flags);
                if (rc != 0) {
                        ipgpc_filter_destructor(filter);
                }
                kmem_free(filter, sizeof (ipgpc_filter_t));
                break;
        case CLASSIFIER_ADD_CLASS: /* add a class */
                aclass = kmem_zalloc(sizeof (ipgpc_class_t), KM_SLEEP);
                if ((rc = ipgpc_parse_class(aclass, nvlp)) != 0) {
                        ipgpc0dbg(("ipgpc_modify_action: invalid class"));
                        kmem_free(aclass, sizeof (ipgpc_class_t));
                        break;
                }
                rc = ipgpc_addclass(aclass, flags);
                kmem_free(aclass, sizeof (ipgpc_class_t));
                break;
        case CLASSIFIER_REMOVE_FILTER: /* remove a filter */
                /* parse filter name */
                if ((rc = nvlist_lookup_string(nvlp, CLASSIFIER_FILTER_NAME,
                    &name)) != 0) {
                        ipgpc0dbg(("ipgpc_modify_action: filtername missing"));
                        break;
                }
                /* parse optional filter_instance */
                if (nvlist_lookup_int32(nvlp, IPGPC_FILTER_INSTANCE,
                    &filter_instance) != 0) {
                        filter_instance = -1;
                }
                rc = ipgpc_removefilter(name, filter_instance, flags);
                break;
        case CLASSIFIER_REMOVE_CLASS: /* remove a class */
                /* parse class name */
                if ((rc = nvlist_lookup_string(nvlp, CLASSIFIER_CLASS_NAME,
                    &name)) != 0) {
                        ipgpc0dbg(("ipgpc_modify_action: class name missing"));
                        break;
                }
                rc = ipgpc_removeclass(name, flags);
                break;
        case CLASSIFIER_MODIFY_FILTER: /* modify a filter */
                rc = ipgpc_modifyfilter(&nvlp, flags);
                break;
        case CLASSIFIER_MODIFY_CLASS: /* modify a class */
                rc = ipgpc_modifyclass(&nvlp, flags);
                break;
        default:                /* invalid config type */
                nvlist_free(nvlp);
                ipgpc0dbg(("ipgpc_modify_action:invalid configuration type %u",
                    config_type));
                return (EINVAL);
        }
        nvlist_free(nvlp);      /* free the list */
        return (rc);            /* nvlist is passed back NULL */
}

/*
 * ipgpc_destroy_action(aid, flags)
 *
 * action destructor for ipgpc
 *
 * Destroys an instance of the ipgpc action, if one exists. The
 * ipgpc_action_lock is taken to block out any other destroys or creates
 * that might be issued while the action is being destroyed
 */
/* ARGSUSED */
static int
ipgpc_destroy_action(ipp_action_id_t aid, ipp_flags_t flags)
{
        /* only destroy action if it exists */
        if (ipgpc_action_exist == B_TRUE) {
                mutex_enter(&ipgpc_config_lock);
                if (ipgpc_action_exist == B_FALSE) {
                        mutex_exit(&ipgpc_config_lock);
                        return (EBUSY);
                }
                ipgpc_action_exist = B_FALSE;
                ipgpc_destroy(flags);
                mutex_exit(&ipgpc_config_lock);
        }
        return (0);
}

/*
 * ipgpc_info(aid, fn, arg)
 *
 * configuration quering function for ipgpc
 *
 * passes back the configuration of ipgpc through allocated nvlists
 * all action paramaters, classes and filters are built into nvlists
 * and passed to the function pointer fn with arg
 */
/* ARGSUSED */
static int
ipgpc_info(ipp_action_id_t aid, int (*fn)(nvlist_t *, void *), void *arg,
    ipp_flags_t flags)
{
        int rc;

        /* set parameters */
        if ((rc = ipgpc_params_info(fn, arg)) != 0) {
                return (rc);
        }

        /* set all classes */
        if ((rc = ipgpc_classes_info(fn, arg)) != 0) {
                return (rc);
        }

        /* set all filters */
        if ((rc = ipgpc_filters_info(fn, arg)) != 0) {
                return (rc);
        }
        return (0);
}

/*
 * ipgpc_invoke_action(aid, packet)
 *
 * packet processing function for ipgpc
 *
 * given packet the selector information is parsed and the classify
 * function is called with those selectors.  The classify function will
 * return either a class or NULL, which represents a memory error and
 * ENOMEM is returned.  If the class returned is not NULL, the class and next
 * action, associated with that class, are added to packet
 */
/* ARGSUSED */
static int
ipgpc_invoke_action(ipp_action_id_t aid, ipp_packet_t *packet)
{
        ipgpc_class_t *out_class;
        hrtime_t start, end;
        mblk_t *mp = NULL;
        ip_priv_t *priv = NULL;
        ill_t *ill = NULL;
        ipha_t *ipha;
        ip_proc_t callout_pos;
        int af;
        int rc;
        ipgpc_packet_t pkt;
        uint_t ill_idx;

        /* extract packet data */
        mp = ipp_packet_get_data(packet);
        ASSERT(mp != NULL);

        priv = (ip_priv_t *)ipp_packet_get_private(packet);
        ASSERT(priv != NULL);

        callout_pos = priv->proc;
        ill_idx = priv->ill_index;

        /* If we don't get an M_DATA, then return an error */
        if (mp->b_datap->db_type != M_DATA) {
                if ((mp->b_cont != NULL) &&
                    (mp->b_cont->b_datap->db_type == M_DATA)) {
                        mp = mp->b_cont; /* jump over the M_CTL into M_DATA */
                } else {
                        ipgpc0dbg(("ipgpc_invoke_action: no data\n"));
                        atomic_inc_64(&ipgpc_epackets);
                        return (EINVAL);
                }
        }

        /*
         * Translate the callout_pos into the direction the packet is traveling
         */
        if (callout_pos != IPP_LOCAL_IN) {
                if (callout_pos & IPP_LOCAL_OUT) {
                        callout_pos = IPP_LOCAL_OUT;
                } else if (callout_pos & IPP_FWD_IN) {
                        callout_pos = IPP_FWD_IN;
                } else {        /* IPP_FWD_OUT */
                        callout_pos = IPP_FWD_OUT;
                }
        }

        /* parse the packet from the message block */
        ipha = (ipha_t *)mp->b_rptr;
        /* Determine IP Header Version */
        if (IPH_HDR_VERSION(ipha) == IPV4_VERSION) {
                parse_packet(&pkt, mp);
                af = AF_INET;
        } else {
                parse_packet6(&pkt, mp);
                af = AF_INET6;
        }

        pkt.direction = callout_pos; /* set packet direction */

        /* The ill_index could be 0 when called from forwarding (read) path */
        if (ill_idx > 0)
                ill = ill_lookup_on_ifindex_global_instance(ill_idx, B_FALSE);

        if (ill != NULL) {
                /*
                 * Since all IPP actions in an IPMP group are performed
                 * relative to the IPMP group interface, if this is an
                 * underlying interface in an IPMP group, use the IPMP
                 * group interface's index.
                 */
                if (IS_UNDER_IPMP(ill))
                        pkt.if_index = ipmp_ill_get_ipmp_ifindex(ill);
                else
                        pkt.if_index = ill->ill_phyint->phyint_ifindex;
                /* Got the field from the ILL, go ahead and refrele */
                ill_refrele(ill);
        } else {
                /* unknown if_index */
                pkt.if_index = IPGPC_UNSPECIFIED;
        }

        if (ipgpc_debug > 5) {
                /* print pkt under high debug level */
#ifdef  IPGPC_DEBUG
                print_packet(af, &pkt);
#endif
        }
        if (ipgpc_debug > 3) {
                start = gethrtime(); /* start timer */
        }

        /* classify this packet */
        out_class = ipgpc_classify(af, &pkt);

        if (ipgpc_debug > 3) {
                end = gethrtime(); /* stop timer */
        }

        /* ipgpc_classify will only return NULL if a memory error occured */
        if (out_class == NULL) {
                atomic_inc_64(&ipgpc_epackets);
                return (ENOMEM);
        }

        ipgpc1dbg(("ipgpc_invoke_action: class = %s", out_class->class_name));
        /* print time to classify(..) */
        ipgpc2dbg(("ipgpc_invoke_action: time = %lld nsec\n", (end - start)));

        if ((rc = ipp_packet_add_class(packet, out_class->class_name,
            out_class->next_action)) != 0) {
                atomic_inc_64(&ipgpc_epackets);
                ipgpc0dbg(("ipgpc_invoke_action: ipp_packet_add_class " \
                    "failed with error %d", rc));
                return (rc);
        }
        return (ipp_packet_next(packet, IPP_ACTION_CONT));
}