libsmbfs/common/smbfs_nb.c

/*
 * Copyright (c) 2000, 2001 Boris Popov
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by Boris Popov.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $Id: nb.c,v 1.1.1.2 2001/07/06 22:38:42 conrad Exp $
 */

/*
 * Copyright (c) 2008, 2012, Oracle and/or its affiliates. All rights reserved.
 */

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

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <libintl.h>
#include <netdb.h>
#include <nss_dbdefs.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <err.h>
#include <netsmb/netbios.h>
#include "smbfs_lib.h"
#include "smbfs_nb_lib.h"
#include "smbfs_private.h"
#include <smbsrv/libsmb.h>

int
smbfs_nb_ctx_create(struct nb_ctx **ctxpp)
{
    struct nb_ctx *ctx;

    ctx = malloc(sizeof (struct nb_ctx));
    if (ctx == NULL)
        return (ENOMEM);
    bzero(ctx, sizeof (struct nb_ctx));
    *ctxpp = ctx;
    return (0);
}

void
smbfs_nb_ctx_done(struct nb_ctx *ctx)
{
    if (ctx == NULL)
        return;
    if (ctx->nb_scope)
        free(ctx->nb_scope);
    if (ctx)
        free(ctx);
}

void
smbfs_nb_ctx_setnbflags(struct nb_ctx *nb, int ns_ena, int bc_ena)
{
    nb->nb_flags &= ~(NBCF_NS_ENABLE | NBCF_BC_ENABLE);
    if (ns_ena) {
        nb->nb_flags |= NBCF_NS_ENABLE;
        if (bc_ena)
            nb->nb_flags |= NBCF_BC_ENABLE;
    }
}

int
smbfs_nb_ctx_setwins(struct nb_ctx *ctx, const char *wins1, const char *wins2)
{
    struct in_addr ina;
    int error;

    if (wins1 == NULL) {
        ctx->nb_wins1 = 0;
        ctx->nb_wins2 = 0;
        return (0);
    }

    error = smbfs_nb_resolvehost_in(wins1, &ina);
    if (error) {
        smbfs_error(dgettext(TEXT_DOMAIN, "can't resolve %s"),
            error, wins1);
        return (error);
    }
    ctx->nb_wins1 = ina.s_addr;

    if (wins2 == NULL)
        ctx->nb_wins2 = 0;
    else {
        error = smbfs_nb_resolvehost_in(wins2, &ina);
        if (error) {
            smbfs_error(dgettext(TEXT_DOMAIN, "can't resolve %s"),
                error, wins2);
            return (error);
        }
        ctx->nb_wins2 = ina.s_addr;
    }
    return (0);
}

/*
 * This is called by "smbutil lookup" to handle the
 * "-w wins_server" option.  Let the semantics of
 * this option be: Use specified WINS server only.
 * If specified server is the broadcast address,
 * set broadcast mode (and no WINS servers).
 */
int
smbfs_nb_ctx_setns(struct nb_ctx *ctx, const char *addr)
{
    int error;

    error = smbfs_nb_ctx_setwins(ctx, addr, NULL);
    if (error)
        return (error);

    /* Deal with explicit request for broadcast. */
    if (ctx->nb_wins1 == INADDR_BROADCAST) {
        ctx->nb_wins1 = 0;
        ctx->nb_flags |= NBCF_BC_ENABLE;
    }
    return (0);
}

int
smbfs_nb_ctx_setscope(struct nb_ctx *ctx, const char *scope)
{
    size_t slen = strlen(scope);

    if (slen >= 128) {
        smbfs_error(dgettext(TEXT_DOMAIN,
            "scope '%s' is too long"), 0, scope);
        return (ENAMETOOLONG);
    }
    if (ctx->nb_scope)
        free(ctx->nb_scope);
    ctx->nb_scope = malloc(slen + 1);
    if (ctx->nb_scope == NULL)
        return (ENOMEM);
    (void) smbfs_nls_str_upper(ctx->nb_scope, scope);
    return (0);
}

/*
 * Now get the WINS server IP addresses directly
 * when reading the RC files, so no longer need to
 * lookup any names here.
 */
int
smbfs_nb_ctx_resolve(struct nb_ctx *ctx)
{
    ctx->nb_flags |= NBCF_RESOLVED;
    return (0);
}

/*
 * For defaults, enable NetBIOS name lookup and NetBIOS lookup via broadcast.
 * These settings are not configurable.
 */
int
smbfs_nb_ctx_getconfigs(struct nb_ctx *ctx)
{
    char ipstr1[16], ipstr2[16];
    char *wins1 = NULL, *wins2 = NULL;

    smbfs_nb_ctx_setnbflags(ctx, TRUE, TRUE);

    if (smb_config_getstr(SMB_CI_WINS_SRV1, ipstr1, sizeof (ipstr1)) ==
        SMBD_SMF_OK)
        if (*ipstr1 != '\0')
            wins1 = ipstr1;

    if (smb_config_getstr(SMB_CI_WINS_SRV2, ipstr2, sizeof (ipstr2)) ==
        SMBD_SMF_OK)
        if (*ipstr2 != '\0')
            wins2 = ipstr2;

    return (smbfs_nb_ctx_setwins(ctx, wins1, wins2));
}

/*
 * General networking stuff, in spite of the names
 * that imply they're specific to NetBIOS.
 */
int
smbfs_nb_resolvehost_in(const char *name, struct in_addr *ia)
{
    char  he_buf[NSS_BUFLEN_HOSTS];
    struct hostent he, *h;
    int err;

    h = gethostbyname_r(name, &he, he_buf, sizeof (he_buf), &err);
    if (h == NULL) {
#ifdef DEBUG
        warnx("can't get server address `%s': ", name);
#endif
        return (ENETDOWN);
    }
    if (h->h_addrtype != AF_INET) {
#ifdef DEBUG
        warnx("address for `%s' is not in the AF_INET family", name);
#endif
        return (EAFNOSUPPORT);
    }
    if (h->h_length != 4) {
#ifdef DEBUG
        warnx("address for `%s' has invalid length", name);
#endif
        return (EAFNOSUPPORT);
    }

    (void) memcpy(ia, h->h_addr, sizeof (*ia));
    return (0);
}

static const char *nb_err_rcode[] = {
    "bad request/response format",
    "NBNS server failure",
    "no such name",
    "unsupported request",
    "request rejected",
    "name already registered"
};

static const char *nb_err[] = {
    "host not found",
    "too many redirects",
    "invalid response",
    "NETBIOS name too long",
    "no interface to broadcast on and no NBNS server specified"
};

const char *
smbfs_nb_strerror(int error)
{
    if (error == 0)
        return (NULL);
    if (error <= NBERR_ACTIVE)
        return (nb_err_rcode[error - 1]);
    else if (error >= NBERR_HOSTNOTFOUND && error < NBERR_MAX)
        return (nb_err[error - NBERR_HOSTNOTFOUND]);
    else
        return (NULL);
}

/* Netbios name encoding functions. Moved from smbfs_nb_name.c */
int
smbfs_nb_name_enc_len(const uchar_t *str)
{
    const uchar_t *cp = str;
    int len, blen;

    if ((cp[0] & 0xc0) == 0xc0)
        return (-1);    /* first two bytes are offset to name */

    len = 1;
    for (;;) {
        blen = *cp;
        if (blen++ == 0)
            break;
        len += blen;
        cp += blen;
    }
    return (len);
}

int
smbfs_nb_name_encode(struct mbdata *mbp, struct nb_name *nn)
{
    char *plen;
    uchar_t ch;
    char *p, namebuf[NB_NAMELEN+1];
    int i, lblen;

    bcopy(nn->nn_name, namebuf, NB_NAMELEN);
    namebuf[NB_NAMELEN-1] = (char)nn->nn_type;
    namebuf[NB_NAMELEN] = '\0'; /* for debug */

    /*
     * Do the NetBIOS "first-level encoding" here.
     * (RFC1002 explains this weirdness...)
     *
     * Here is what we marshall:
     *   uint8_t NAME_LENGTH (always 32)
     *   uint8_t ENCODED_NAME[32]
     *   uint8_t SCOPE_LENGTH
     *   Scope follows here, then another null.
     */

    /* NAME_LENGTH */
    smbfs_mb_put_uint8(mbp, (2 * NB_NAMELEN));

    /* ENCODED_NAME */
    for (i = 0; i < NB_NAMELEN; i++) {
        ch = namebuf[i];
        smbfs_mb_put_uint8(mbp, 'A' + ((ch >> 4) & 0xF));
        smbfs_mb_put_uint8(mbp, 'A' + ((ch) & 0xF));
    }

    /*
     * NetBIOS "scope" sting encoding,
     * a.k.a second-level encoding.
     * See RFC1002 for the details.
     *
     * Note: plen points to the length byte at the
     * start of each string.  This keeps a pointer
     * to the location and fills it in after the
     * length of the string is determined.
     *
     * One string of length zero terminates.
     * With no scope string, the zero-length
     * string is the only thing there.
     */
    if (nn->nn_scope == NULL) {
        smbfs_mb_put_uint8(mbp, 0);
        return (0);
    }

    (void) smbfs_mb_fit(mbp, 1, &plen);
    *plen = 0; /* will update below */
    lblen = 0;
    for (p = nn->nn_scope; ; p++) {
        if (*p == '\0') {
            *plen = lblen;
            if (lblen)
                smbfs_mb_put_uint8(mbp, 0);
            break;
        }
        if (*p == '.') {
            *plen = lblen;
            (void) smbfs_mb_fit(mbp, 1, &plen);
            *plen = 0;
            lblen = 0;
        } else {
            if (lblen < NB_MAXLABLEN) {
                smbfs_mb_put_uint8(mbp, *p);
                lblen++;
            }
        }
    }

    return (0);
}