/*      $NetBSD: vendorid.c,v 1.11 2025/03/08 16:39:08 christos Exp $   */

/* Id: vendorid.c,v 1.10 2006/02/22 16:10:21 vanhu Exp */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "config.h"

#include <sys/types.h>
#include <sys/param.h>

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>

#include "var.h"
#include "misc.h"
#include "vmbuf.h"
#include "plog.h"
#include "debug.h"

#include "localconf.h"
#include "isakmp_var.h"
#include "isakmp.h"
#include "vendorid.h"
#include "crypto_openssl.h"
#include "handler.h"
#include "remoteconf.h"
#ifdef ENABLE_NATT
#include "nattraversal.h"
#endif
#ifdef ENABLE_HYBRID
#include <resolv.h>
#include "isakmp_xauth.h"
#include "isakmp_cfg.h"
#endif

static struct vendor_id all_vendor_ids[] = {
{ VENDORID_IPSEC_TOOLS, "IPSec-Tools", NULL },
{ VENDORID_GSSAPI_LONG, "A GSS-API Authentication Method for IKE", NULL },
{ VENDORID_GSSAPI     , "GSSAPI", NULL },
{ VENDORID_MS_NT5     , "MS NT5 ISAKMPOAKLEY", NULL },
{ VENDORID_NATT_00    , "draft-ietf-ipsec-nat-t-ike-00", NULL },
{ VENDORID_NATT_01    , "draft-ietf-ipsec-nat-t-ike-01", NULL },
{ VENDORID_NATT_02    , "draft-ietf-ipsec-nat-t-ike-02", NULL },
{ VENDORID_NATT_02_N  , "draft-ietf-ipsec-nat-t-ike-02\n", NULL },
{ VENDORID_NATT_03    , "draft-ietf-ipsec-nat-t-ike-03", NULL },
{ VENDORID_NATT_04    , "draft-ietf-ipsec-nat-t-ike-04", NULL },
{ VENDORID_NATT_05    , "draft-ietf-ipsec-nat-t-ike-05", NULL },
{ VENDORID_NATT_06    , "draft-ietf-ipsec-nat-t-ike-06", NULL },
{ VENDORID_NATT_07    , "draft-ietf-ipsec-nat-t-ike-07", NULL },
{ VENDORID_NATT_08    , "draft-ietf-ipsec-nat-t-ike-08", NULL },
{ VENDORID_NATT_RFC   , "RFC 3947", NULL },
{ VENDORID_XAUTH      , "draft-ietf-ipsra-isakmp-xauth-06.txt", NULL },
{ VENDORID_UNITY      , "CISCO-UNITY", NULL },
{ VENDORID_FRAG       , "FRAGMENTATION", NULL },
/* Just a readable string for DPD ... */
{ VENDORID_DPD        , "DPD", NULL },
/* Other known Vendor IDs */
{ VENDORID_KAME       , "KAME/racoon", NULL },
};

#define NUMVENDORIDS    (sizeof(all_vendor_ids)/sizeof(all_vendor_ids[0]))

#define DPD_MAJOR_VERSION       0x01
#define DPD_MINOR_VERSION       0x00

static const unsigned char vendorid_dpd_hash[] = {
        0xAF, 0xCA, 0xD7, 0x13,
        0x68, 0xA1, 0xF1, 0xC9,
        0x6B, 0x86, 0x96, 0xFC,
        0x77, 0x57, DPD_MAJOR_VERSION, DPD_MINOR_VERSION
};


static vchar_t *vendorid_fixup(int, vchar_t *t);

static struct vendor_id *
lookup_vendor_id_by_id (int id)
{
        int i;

        for (i = 0; i < NUMVENDORIDS; i++)
                if (all_vendor_ids[i].id == id)
                        return &all_vendor_ids[i];

        return NULL;
}

const char *
vid_string_by_id (int id)
{
        struct vendor_id *current;

        if (id == VENDORID_DPD)
                return (const char *)vendorid_dpd_hash;

        current = lookup_vendor_id_by_id(id);

        return current ? current->string : NULL;
}

static struct vendor_id *
lookup_vendor_id_by_hash (const char *hash)
{
        int i;

        for (i = 0; i < NUMVENDORIDS; i++)
                if (strncmp(all_vendor_ids[i].hash->v, hash,
                            all_vendor_ids[i].hash->l) == 0)
                        return &all_vendor_ids[i];

        return NULL;
}

void
compute_vendorids (void)
{
        int i;
        vchar_t vid;

        for (i = 0; i < NUMVENDORIDS; i++) {
                /* VENDORID_DPD is not a MD5 sum... */
                if(all_vendor_ids[i].id == VENDORID_DPD){
                        all_vendor_ids[i].hash = vmalloc(sizeof(vendorid_dpd_hash));
                        if (all_vendor_ids[i].hash == NULL) {
                                plog(LLV_ERROR, LOCATION, NULL,
                                        "unable to get memory for VID hash\n");
                                exit(1); /* this really shouldn't happen */
                        }
                        memcpy(all_vendor_ids[i].hash->v, vendorid_dpd_hash,
                                   sizeof(vendorid_dpd_hash));
                        continue;
                }

                vid.v = (char *)(intptr_t)all_vendor_ids[i].string;
                vid.l = strlen(vid.v);

                all_vendor_ids[i].hash = eay_md5_one(&vid);
                if (all_vendor_ids[i].hash == NULL)
                        plog(LLV_ERROR, LOCATION, NULL,
                            "unable to hash vendor ID string\n");

                /* Special cases */
                all_vendor_ids[i].hash =
                        vendorid_fixup(all_vendor_ids[i].id,
                                       all_vendor_ids[i].hash);
        }
}

/*
 * set hashed vendor id.
 * hash function is always MD5.
 */
vchar_t *
set_vendorid(int vendorid)
{
        struct vendor_id *current;

        if (vendorid == VENDORID_UNKNOWN) {
                /*
                 * The default unknown ID gets translated to
                 * KAME/racoon.
                 */
                vendorid = VENDORID_DEFAULT;
        }

        current = lookup_vendor_id_by_id(vendorid);
        if (current == NULL) {
                plog(LLV_ERROR, LOCATION, NULL,
                    "invalid vendor ID index: %d\n", vendorid);
                return (NULL);
        }

        /* The rest of racoon expects a private copy 
         * of the VID that could be free'd after use.
         * That's why we don't return the original pointer. */
        return vdup(current->hash);
}

/*
 * Check the vendor ID payload -- return the vendor ID index
 * if we find a recognized one, or UNKNOWN if we don't.
 *
 * gen ... points to Vendor ID payload.
 */
static int
check_vendorid(struct isakmp_gen *gen)
{
        int vidlen;
        struct vendor_id *current;

        if (gen == NULL)
                return (VENDORID_UNKNOWN);

        vidlen = ntohs(gen->len) - sizeof(*gen);

        current = lookup_vendor_id_by_hash((char *)(gen + 1));
        if (!current)
                goto unknown;
        
        if (current->hash->l < vidlen)
                plog(LLV_INFO, LOCATION, NULL,
                     "received broken Microsoft ID: %s\n",
                     current->string);
        else
                plog(LLV_INFO, LOCATION, NULL,
                     "received Vendor ID: %s\n",
                     current->string);

        return current->id;

unknown:
        plog(LLV_DEBUG, LOCATION, NULL, "received unknown Vendor ID\n");
        plogdump(LLV_DEBUG, (char *)(gen + 1), vidlen);
        return (VENDORID_UNKNOWN);
}

int
handle_vendorid(struct ph1handle *iph1, struct isakmp_gen *gen)
{
        int vid_numeric;

        vid_numeric = check_vendorid(gen);
        if (vid_numeric == VENDORID_UNKNOWN)
                return vid_numeric;

        iph1->vendorid_mask |= BIT(vid_numeric);

#ifdef ENABLE_NATT
        if (natt_vendorid(vid_numeric))
                natt_handle_vendorid(iph1, vid_numeric);
#endif
#ifdef ENABLE_HYBRID
        switch (vid_numeric) {
        case VENDORID_XAUTH:
                iph1->mode_cfg->flags |= ISAKMP_CFG_VENDORID_XAUTH;
                break;
        case VENDORID_UNITY:
                iph1->mode_cfg->flags |= ISAKMP_CFG_VENDORID_UNITY;
                break;
        default:
                break;
        }
#endif
#ifdef ENABLE_DPD
        if (vid_numeric == VENDORID_DPD &&
            (iph1->rmconf == NULL || iph1->rmconf->dpd)) {
                iph1->dpd_support = 1;
                plog(LLV_DEBUG, LOCATION, NULL, "remote supports DPD\n");
        }
#endif

        return vid_numeric;
}

static vchar_t * 
vendorid_fixup(int vendorid, vchar_t *vidhash)
{                          
        switch(vendorid) {
        case VENDORID_XAUTH: {  /* The vendor Id is truncated */
                vchar_t *tmp;                                       
                                  
                if ((tmp = vmalloc(8)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "unable to hash vendor ID string\n");
                        return NULL;                                
                }                       
                  
                memcpy(tmp->v, vidhash->v, 8);
                vfree(vidhash);           
                vidhash = tmp;
                                   
                break;
        } 
        case VENDORID_UNITY:    /* Two bytes tweak */
                vidhash->v[14] = 0x01;            
                vidhash->v[15] = 0x00;
                break;             

        default:     
                break;
        }               
        
        return vidhash;
}