/*
 * Copyright (C) 1993-2001, 2003 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#if defined(KERNEL) || defined(_KERNEL)
# undef KERNEL
# undef _KERNEL
# define        KERNEL  1
# define        _KERNEL 1
#endif
#include <sys/param.h>
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/file.h>
#if !defined(_KERNEL)
# include <stdlib.h>
# include <string.h>
# define _KERNEL
# ifdef __OpenBSD__
struct file;
# endif
# include <sys/uio.h>
# undef _KERNEL
#endif
#include <sys/socket.h>
#if defined(__FreeBSD_version) && (__FreeBSD_version >= 300000)
# include <sys/malloc.h>
#endif
#if defined(__FreeBSD__)
#  include <sys/cdefs.h>
#  include <sys/proc.h>
#endif
#if !defined(__svr4__) && !defined(__SVR4) && !defined(__hpux) && \
    !defined(linux)
# include <sys/mbuf.h>
#endif
#if defined(_KERNEL)
# include <sys/systm.h>
#else
# include <stdio.h>
#endif
#include <netinet/in.h>
#include <net/if.h>

#include "netinet/ip_compat.h"
#include "netinet/ip_fil.h"
#include "netinet/ip_lookup.h"
#include "netinet/ip_htable.h"
#include "netinet/ipf_stack.h"
/* END OF INCLUDES */

#if !defined(lint)
static const char rcsid[] = "@(#)$Id: ip_htable.c,v 2.34.2.3 2005/05/14 05:11:38 darrenr Exp $";
#endif

#ifdef  IPFILTER_LOOKUP
static iphtent_t *fr_iphmfind __P((iphtable_t *, struct in_addr *));
#ifdef USE_INET6
static iphtent_t *fr_iphmfind6 __P((iphtable_t *, struct in6_addr *));
static uint32_t sum4(uint32_t *);
static void left_shift_ipv6 __P((char *));
#endif

void fr_htable_unload(ifs)
ipf_stack_t *ifs;
{
        iplookupflush_t fop;

        fop.iplf_unit = IPL_LOGALL;
        (void)fr_flushhtable(&fop, ifs);
}


int fr_gethtablestat(op, ifs)
iplookupop_t *op;
ipf_stack_t *ifs;
{
        iphtstat_t stats;

        if (op->iplo_size != sizeof(stats))
                return EINVAL;

        stats.iphs_tables = ifs->ifs_ipf_htables[op->iplo_unit];
        stats.iphs_numtables = ifs->ifs_ipf_nhtables[op->iplo_unit];
        stats.iphs_numnodes = ifs->ifs_ipf_nhtnodes[op->iplo_unit];
        stats.iphs_nomem = ifs->ifs_ipht_nomem[op->iplo_unit];

        return COPYOUT(&stats, op->iplo_struct, sizeof(stats));

}


/*
 * Create a new hash table using the template passed.
 */
int fr_newhtable(op, ifs)
iplookupop_t *op;
ipf_stack_t *ifs;
{
        iphtable_t *iph, *oiph;
        char name[FR_GROUPLEN];
        int err, i, unit;

        KMALLOC(iph, iphtable_t *);
        if (iph == NULL) {
                ifs->ifs_ipht_nomem[op->iplo_unit]++;
                return ENOMEM;
        }

        err = COPYIN(op->iplo_struct, iph, sizeof(*iph));
        if (err != 0) {
                KFREE(iph);
                return EFAULT;
        }

        unit = op->iplo_unit;
        if (iph->iph_unit != unit) {
                KFREE(iph);
                return EINVAL;
        }

        if ((op->iplo_arg & IPHASH_ANON) == 0) {
                if (fr_findhtable(op->iplo_unit, op->iplo_name, ifs) != NULL) {
                        KFREE(iph);
                        return EEXIST;
                }
        } else {
                i = IPHASH_ANON;
                do {
                        i++;
#if defined(SNPRINTF) && defined(_KERNEL)
                        (void)SNPRINTF(name, sizeof(name), "%u", i);
#else
                        (void)sprintf(name, "%u", i);
#endif
                        for (oiph = ifs->ifs_ipf_htables[unit]; oiph != NULL;
                             oiph = oiph->iph_next)
                                if (strncmp(oiph->iph_name, name,
                                            sizeof(oiph->iph_name)) == 0)
                                        break;
                } while (oiph != NULL);
                (void)strncpy(iph->iph_name, name, sizeof(iph->iph_name));
                err = COPYOUT(iph, op->iplo_struct, sizeof(*iph));
                if (err != 0) {
                        KFREE(iph);
                        return EFAULT;
                }
                iph->iph_type |= IPHASH_ANON;
        }

        KMALLOCS(iph->iph_table, iphtent_t **,
                 iph->iph_size * sizeof(*iph->iph_table));
        if (iph->iph_table == NULL) {
                KFREE(iph);
                ifs->ifs_ipht_nomem[unit]++;
                return ENOMEM;
        }

        bzero((char *)iph->iph_table, iph->iph_size * sizeof(*iph->iph_table));
        iph->iph_masks[0] = 0;
        iph->iph_masks[1] = 0;
        iph->iph_masks[2] = 0;
        iph->iph_masks[3] = 0;
        iph->iph_list = NULL;

        iph->iph_ref = 1;
        iph->iph_next = ifs->ifs_ipf_htables[unit];
        iph->iph_pnext = &ifs->ifs_ipf_htables[unit];
        if (ifs->ifs_ipf_htables[unit] != NULL)
                ifs->ifs_ipf_htables[unit]->iph_pnext = &iph->iph_next;
        ifs->ifs_ipf_htables[unit] = iph;

        ifs->ifs_ipf_nhtables[unit]++;

        return 0;
}


/*
 */
int fr_removehtable(op, ifs)
iplookupop_t *op;
ipf_stack_t *ifs;
{
        iphtable_t *iph;


        iph = fr_findhtable(op->iplo_unit, op->iplo_name, ifs);
        if (iph == NULL)
                return ESRCH;

        if (iph->iph_unit != op->iplo_unit) {
                return EINVAL;
        }

        if (iph->iph_ref != 1) {
                return EBUSY;
        }

        fr_delhtable(iph, ifs);

        return 0;
}


void fr_delhtable(iph, ifs)
iphtable_t *iph;
ipf_stack_t *ifs;
{
        iphtent_t *ipe;
        int i;

        for (i = 0; i < iph->iph_size; i++)
                while ((ipe = iph->iph_table[i]) != NULL)
                        if (fr_delhtent(iph, ipe, ifs) != 0)
                                return;

        *iph->iph_pnext = iph->iph_next;
        if (iph->iph_next != NULL)
                iph->iph_next->iph_pnext = iph->iph_pnext;

        ifs->ifs_ipf_nhtables[iph->iph_unit]--;

        if (iph->iph_ref == 1) {
                KFREES(iph->iph_table, iph->iph_size * sizeof(*iph->iph_table));
                KFREE(iph);
        }
}


void fr_derefhtable(iph, ifs)
iphtable_t *iph;
ipf_stack_t *ifs;
{
        iph->iph_ref--;
        if (iph->iph_ref == 0)
                fr_delhtable(iph, ifs);
}


void fr_derefhtent(ipe)
iphtent_t *ipe;
{
        ipe->ipe_ref--;
        if (ipe->ipe_ref == 0) {
                KFREE(ipe);
        }
}


iphtable_t *fr_findhtable(unit, name, ifs)
int unit;
char *name;
ipf_stack_t *ifs;
{
        iphtable_t *iph;

        for (iph = ifs->ifs_ipf_htables[unit]; iph != NULL; iph = iph->iph_next)
                if (strncmp(iph->iph_name, name, sizeof(iph->iph_name)) == 0)
                        break;
        return iph;
}


size_t fr_flushhtable(op, ifs)
iplookupflush_t *op;
ipf_stack_t *ifs;
{
        iphtable_t *iph;
        size_t freed;
        int i;

        freed = 0;

        for (i = 0; i <= IPL_LOGMAX; i++) {
                if (op->iplf_unit == i || op->iplf_unit == IPL_LOGALL) {
                        while ((iph = ifs->ifs_ipf_htables[i]) != NULL) {
                                fr_delhtable(iph, ifs);
                                freed++;
                        }
                }
        }

        return freed;
}


/*
 * Add an entry to a hash table.
 */
int fr_addhtent(iph, ipeo, ifs)
iphtable_t *iph;
iphtent_t *ipeo;
ipf_stack_t *ifs;
{
        iphtent_t *ipe;
        u_int hv;
        int bits;

        KMALLOC(ipe, iphtent_t *);
        if (ipe == NULL)
                return -1;

        bcopy((char *)ipeo, (char *)ipe, sizeof(*ipe));
#ifdef USE_INET6
        if (ipe->ipe_family == AF_INET6) {
                bits = count6bits((u_32_t *)ipe->ipe_mask.in6_addr8);
                hv = IPE_HASH_FN(sum4((uint32_t *)ipe->ipe_addr.in6_addr8),
                                 sum4((uint32_t *)ipe->ipe_mask.in6_addr8),
                                 iph->iph_size);
        } else
#endif
        if (ipe->ipe_family == AF_INET)
        {
                ipe->ipe_addr.in4_addr &= ipe->ipe_mask.in4_addr;
                ipe->ipe_addr.in4_addr = ntohl(ipe->ipe_addr.in4_addr);
                bits = count4bits(ipe->ipe_mask.in4_addr);
                ipe->ipe_mask.in4_addr = ntohl(ipe->ipe_mask.in4_addr);

                hv = IPE_HASH_FN(ipe->ipe_addr.in4_addr, ipe->ipe_mask.in4_addr,
                                 iph->iph_size);
        } else
                return -1;

        ipe->ipe_ref = 1;
        ipe->ipe_next = iph->iph_table[hv];
        ipe->ipe_pnext = iph->iph_table + hv;

        if (iph->iph_table[hv] != NULL)
                iph->iph_table[hv]->ipe_pnext = &ipe->ipe_next;
        iph->iph_table[hv] = ipe;

        ipe->ipe_snext = iph->iph_list;
        ipe->ipe_psnext = &iph->iph_list;
        if (ipe->ipe_next != NULL)
                ipe->ipe_next->ipe_psnext = &ipe->ipe_snext;
        iph->iph_list = ipe;

#ifdef USE_INET6
        if (ipe->ipe_family == AF_INET6) {
                if ((bits >= 0) && (bits != 128))
                        if (bits >= 96)
                                iph->iph_masks[0] |= 1 << (bits - 96);
                        else if (bits >= 64)
                                iph->iph_masks[1] |= 1 << (bits - 64);
                        else if (bits >= 32)
                                iph->iph_masks[2] |= 1 << (bits - 32);
                        else
                                iph->iph_masks[3] |= 1 << bits;

        } else
#endif
        {
                if ((bits >= 0) && (bits != 32))
                        iph->iph_masks[3] |= 1 << bits;
        }

        switch (iph->iph_type & ~IPHASH_ANON)
        {
        case IPHASH_GROUPMAP :
                ipe->ipe_ptr = fr_addgroup(ipe->ipe_group, NULL,
                                           iph->iph_flags, IPL_LOGIPF,
                                           ifs->ifs_fr_active, ifs);
                break;

        default :
                ipe->ipe_ptr = NULL;
                ipe->ipe_value = 0;
                break;
        }

        ifs->ifs_ipf_nhtnodes[iph->iph_unit]++;

        return 0;
}


/*
 * Delete an entry from a hash table.
 */
int fr_delhtent(iph, ipe, ifs)
iphtable_t *iph;
iphtent_t *ipe;
ipf_stack_t *ifs;
{
        if (ipe->ipe_ref != 1)
                return EBUSY;


        *ipe->ipe_pnext = ipe->ipe_next;
        if (ipe->ipe_next != NULL)
                ipe->ipe_next->ipe_pnext = ipe->ipe_pnext;

        switch (iph->iph_type & ~IPHASH_ANON)
        {
        case IPHASH_GROUPMAP :
                fr_delgroup(ipe->ipe_group, IPL_LOGIPF,
                    ifs->ifs_fr_active, ifs);
                break;

        default :
                ipe->ipe_ptr = NULL;
                ipe->ipe_value = 0;
                break;
        }

        KFREE(ipe);

        ifs->ifs_ipf_nhtnodes[iph->iph_unit]--;

        return 0;
}


void *fr_iphmfindgroup(tptr, version, aptr, ifs)
void *tptr;
int version;
void *aptr;
ipf_stack_t *ifs;
{
        i6addr_t *addr;
        iphtable_t *iph;
        iphtent_t *ipe;
        void *rval;

        if ((version != 4)
#ifdef USE_INET6
            && (version != 6)
#endif
            )
                return NULL;

        READ_ENTER(&ifs->ifs_ip_poolrw);
        iph = tptr;
        addr = aptr;

#ifdef USE_INET6
        if (version == 6)
                ipe = fr_iphmfind6(iph, &addr->in6);
        else
#endif
        if (version == 4)
                ipe = fr_iphmfind(iph, &addr->in4);
        else
                ipe = NULL;
        if (ipe != NULL)
                rval = ipe->ipe_ptr;
        else
                rval = NULL;
        RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
        return rval;
}


/* ------------------------------------------------------------------------ */
/* Function:    fr_iphmfindip                                               */
/* Returns:     int     - 0 == +ve match, -1 == error, 1 == -ve/no match    */
/* Parameters:  tptr(I)    - pointer to the pool to search                  */
/*              version(I) - IP protocol version (4 or 6)                   */
/*              aptr(I)    - pointer to address information                 */
/*              fin        - pointer to packet information                  */
/*              ifs        - ipf stack instance                             */
/*                                                                          */
/* Search the hash table for a given address and return a search result.    */
/* ------------------------------------------------------------------------ */
int fr_iphmfindip(tptr, version, aptr, fin, ifs)
void *tptr, *aptr;
int version;
fr_info_t *fin;
ipf_stack_t *ifs;
{
        i6addr_t *addr;
        iphtable_t *iph;
        iphtent_t *ipe;
        int rval;

        if ((version != 4)
#ifdef USE_INET6
            && (version != 6)
#endif
            )
                return -1;

        if (tptr == NULL || aptr == NULL)
                return -1;

        iph = tptr;
        addr = aptr;

        READ_ENTER(&ifs->ifs_ip_poolrw);
#ifdef USE_INET6
        if (version == 6)
                ipe = fr_iphmfind6(iph, &addr->in6);
        else
#endif
        if (version == 4)
                ipe = fr_iphmfind(iph, &addr->in4);
        else
                ipe = NULL;
        if (ipe != NULL) {
                ipe->ipe_hits++;
                ipe->ipe_bytes += fin->fin_plen;
                rval = 0;
        } else {
                rval = 1;
        }
        RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
        return rval;
}


/* Locks:  ip_poolrw */
static iphtent_t *fr_iphmfind(iph, addr)
iphtable_t *iph;
struct in_addr *addr;
{
        u_32_t hmsk, msk, ips;
        iphtent_t *ipe;
        u_int hv;

        hmsk = iph->iph_masks[3];
        msk = 0xffffffff;
maskloop:
        ips = ntohl(addr->s_addr) & msk;
        hv = IPE_HASH_FN(ips, msk, iph->iph_size);
        for (ipe = iph->iph_table[hv]; (ipe != NULL); ipe = ipe->ipe_next) {
                if (ipe->ipe_mask.in4_addr != msk ||
                    ipe->ipe_addr.in4_addr != ips) {
                        continue;
                }
                break;
        }

        if ((ipe == NULL) && (hmsk != 0)) {
                while (hmsk != 0) {
                        msk <<= 1;
                        if (hmsk & 0x80000000)
                                break;
                        hmsk <<= 1;
                }
                if (hmsk != 0) {
                        hmsk <<= 1;
                        goto maskloop;
                }
        }
        return ipe;
}


#ifdef USE_INET6
/* Locks:  ip_poolrw */
static iphtent_t *fr_iphmfind6(iph, addr)
iphtable_t *iph;
struct in6_addr *addr;
{
        u_32_t hmsk[4], msk[4], ips[4], *and;
        iphtent_t *ipe;
        u_int hv;

        hmsk[0] = iph->iph_masks[0];
        hmsk[1] = iph->iph_masks[1];
        hmsk[2] = iph->iph_masks[2];
        hmsk[3] = iph->iph_masks[3];

        msk[0] = 0xffffffff;
        msk[1] = 0xffffffff;
        msk[2] = 0xffffffff;
        msk[3] = 0xffffffff;
maskloop:
        and = (u_32_t *)addr->s6_addr;
        ips[0] = *and & msk[0];
        ips[1] = *(and + 1) & msk[1];
        ips[2] = *(and + 2) & msk[2];
        ips[3] = *(and + 3) & msk[3];

        hv = IPE_HASH_FN(sum4((uint32_t *)addr), sum4((uint32_t *)msk),
                              iph->iph_size);
        for (ipe = iph->iph_table[hv]; (ipe != NULL); ipe = ipe->ipe_next) {
                if (bcmp((void *)&ipe->ipe_mask.in6, (void *)msk, 16) ||
                    bcmp((void *)&ipe->ipe_addr.in6, (void *)ips, 16))
                        continue;
                break;
        }

        if ((ipe == NULL) && ((hmsk[0] != 0) ||
                              (hmsk[1] != 0) ||
                              (hmsk[2] != 0) ||
                              (hmsk[3] != 0) )) {
                while ((hmsk[0] != 0) && (hmsk[1] != 0) &&
                       (hmsk[2] != 0) && (hmsk[3] != 0)) {
                        left_shift_ipv6((char *)msk);
                        if (hmsk[0] & 0x80000000)
                                break;
                        left_shift_ipv6((char *)hmsk);
                }
                if ((hmsk[0] != 0) && (hmsk[1] != 0) &&
                    (hmsk[2] != 0) && (hmsk[3] != 0)) {
                        left_shift_ipv6((char *)hmsk);
                        goto maskloop;
                }
        }
        return ipe;
}


/*
 * sum4: ipv6 add -> 4 bytes values
 */
static uint32_t sum4(add)
uint32_t *add;
{
        return (*add + *(add + 1) + *(add + 2) + *(add + 3));
}

/*
 * left shift on 128 bits
 */
static void left_shift_ipv6(data)
char *data;
{
        u_32_t *sd;

        sd = (u_32_t *)data;
        sd[0] <<= 1;
        if (sd[1] >= 0x80000000)
                sd[0] += 1;

        sd[1] <<= 1;
        if (sd[2] >= 0x80000000)
                sd[1] += 1;

        sd[2] <<= 1;
        if (sd[3] >= 0x80000000)
                sd[2] += 1;

        sd[3] <<= 1;
}
#endif

int fr_htable_getnext(token, ilp, ifs)
ipftoken_t *token;
ipflookupiter_t *ilp;
ipf_stack_t *ifs;
{
        iphtent_t *node, zn, *nextnode;
        iphtable_t *iph, zp, *nextiph;
        int err;

        err = 0;
        iph = NULL;
        node = NULL;
        nextiph = NULL;
        nextnode = NULL;

        READ_ENTER(&ifs->ifs_ip_poolrw);

        /*
         * Get "previous" entry from the token and find the next entry.
         *
         * If we found an entry, add a reference to it and update the token.
         * Otherwise, zero out data to be returned and NULL out token.
         */
        switch (ilp->ili_otype)
        {
        case IPFLOOKUPITER_LIST :
                iph = token->ipt_data;
                if (iph == NULL) {
                        nextiph = ifs->ifs_ipf_htables[(int)ilp->ili_unit];
                } else {
                        nextiph = iph->iph_next;
                }
                if (nextiph != NULL) {
                        ATOMIC_INC(nextiph->iph_ref);
                        token->ipt_data = nextiph;
                } else {
                        bzero((char *)&zp, sizeof(zp));
                        nextiph = &zp;
                        token->ipt_data = NULL;
                }
                break;

        case IPFLOOKUPITER_NODE :
                node = token->ipt_data;
                if (node == NULL) {
                        iph = fr_findhtable(ilp->ili_unit, ilp->ili_name, ifs);
                        if (iph == NULL)
                                err = ESRCH;
                        else {
                                nextnode = iph->iph_list;
                        }
                } else {
                        nextnode = node->ipe_snext;
                }
                if (nextnode != NULL) {
                        ATOMIC_INC(nextnode->ipe_ref);
                        token->ipt_data = nextnode;
                } else {
                        bzero((char *)&zn, sizeof(zn));
                        nextnode = &zn;
                        token->ipt_data = NULL;
                }
                break;

        default :
                err = EINVAL;
                break;
        }

        /*
         * Now that we have ref, it's save to give up lock.
         */
        RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
        if (err != 0)
                return err;

        /*
         * Copy out data and clean up references and token as needed.
         */
        switch (ilp->ili_otype)
        {
        case IPFLOOKUPITER_LIST :
                err = COPYOUT(nextiph, ilp->ili_data, sizeof(*nextiph));
                if (err != 0)
                        err = EFAULT;
                if (token->ipt_data == NULL) {
                        ipf_freetoken(token, ifs);
                } else {
                        if (iph != NULL) {
                                WRITE_ENTER(&ifs->ifs_ip_poolrw);
                                fr_derefhtable(iph, ifs);
                                RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
                        }
                        if (nextiph->iph_next == NULL)
                                ipf_freetoken(token, ifs);
                }
                break;

        case IPFLOOKUPITER_NODE :
                err = COPYOUT(nextnode, ilp->ili_data, sizeof(*nextnode));
                if (err != 0)
                        err = EFAULT;
                if (token->ipt_data == NULL) {
                        ipf_freetoken(token, ifs);
                } else {
                        if (node != NULL) {
                                WRITE_ENTER(&ifs->ifs_ip_poolrw);
                                fr_derefhtent(node);
                                RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
                        }
                        if (nextnode->ipe_snext == NULL)
                                ipf_freetoken(token, ifs);
                }
                break;
        }

        return err;
}


void fr_htable_iterderef(otype, unit, data, ifs)
u_int otype;
int unit;
void *data;
ipf_stack_t *ifs;
{

        if (data == NULL)
                return;

        if (unit < 0 || unit > IPL_LOGMAX)
                return;

        switch (otype)
        {
        case IPFLOOKUPITER_LIST :
                WRITE_ENTER(&ifs->ifs_ip_poolrw);
                fr_derefhtable((iphtable_t *)data, ifs);
                RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
                break;

        case IPFLOOKUPITER_NODE :
                WRITE_ENTER(&ifs->ifs_ip_poolrw);
                fr_derefhtent((iphtent_t *)data);
                RWLOCK_EXIT(&ifs->ifs_ip_poolrw);
                break;
        default :
                break;
        }
}
#endif /* IPFILTER_LOOKUP */