root/usr/src/lib/libsmbfs/smb/findvc.c
/*
 * 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.
 *
 * Copyright 2018 Nexenta Systems, Inc.  All rights reserved.
 */

/*
 * Find existing an VC given a list of addresses.
 */

#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <libintl.h>
#include <xti.h>
#include <assert.h>

#include <sys/types.h>
#include <sys/time.h>
#include <sys/byteorder.h>
#include <sys/socket.h>
#include <sys/fcntl.h>

#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>

#include <netsmb/smb.h>
#include <netsmb/smb_lib.h>
#include <netsmb/netbios.h>
#include <netsmb/nb_lib.h>
#include <netsmb/smb_dev.h>

#include "charsets.h"
#include "private.h"

/*
 * Ask the driver if it has a VC with this IP address.
 */
static int
findvc(struct smb_ctx *ctx, struct addrinfo *ai)
{
        smbioc_ossn_t *ssn = &ctx->ct_ssn;

        /*
         * Copy the passed address into ssn_srvaddr,
         * but first sanity-check lengths.  Also,
         * zero it first to avoid trailing junk.
         */
        if (ai->ai_addrlen > sizeof (ssn->ssn_srvaddr))
                return (EINVAL);
        bzero(&ssn->ssn_srvaddr, sizeof (ssn->ssn_srvaddr));
        bcopy(ai->ai_addr, &ssn->ssn_srvaddr, ai->ai_addrlen);

        if (nsmb_ioctl(ctx->ct_dev_fd, SMBIOC_SSN_FIND, ssn) == -1)
                return (errno);

        return (0);
}

/*
 * Find (and reuse) an existing VC.
 * See also: newvc.c
 */
int
smb_ctx_findvc(struct smb_ctx *ctx)
{
        struct addrinfo *ai;
        int err;

        /* Should already have the address list. */
        if ((ctx->ct_flags & SMBCF_RESOLVED) == 0)
                return (EINVAL);

        if (ctx->ct_dev_fd < 0) {
                if ((err = smb_ctx_gethandle(ctx)))
                        return (err);
        }

        for (ai = ctx->ct_addrinfo; ai; ai = ai->ai_next) {

                switch (ai->ai_family) {

                case AF_INET:
                case AF_INET6:
                case AF_NETBIOS:
                        err = findvc(ctx, ai);
                        break;

                default:
                        DPRINT("skipped family %d", ai->ai_family);
                        err = EPROTONOSUPPORT;
                        break;
                }

                if (err == 0) {
                        /* re-use an existing VC */
                        return (0);
                }
        }

        return (ENOENT);
}

/*
 * Forcibly disconnect the current session, even if
 * there are others using it!  This is used by the
 * SMB server netlogon when it wants to setup a new
 * logon session and does not want any re-use.
 */
int
smb_ctx_kill(struct smb_ctx *ctx)
{

        if (nsmb_ioctl(ctx->ct_dev_fd, SMBIOC_SSN_KILL, NULL) == -1)
                return (errno);

        return (0);
}