ldap/common/gethostent.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 (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
 */

#include <netdb.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <syslog.h>
#include <sys/systeminfo.h>
#include <nss.h>
#include "ns_internal.h"
#include "ldap_common.h"

/* host attributes filters */
#define _H_DN           "dn"
#define _H_NAME         "cn"
#define _H_ADDR         "iphostnumber"
#define _F_GETHOSTBYNAME    "(&(objectClass=ipHost)(cn=%s))"
#define _F_GETHOSTBYNAME_SSD    "(&(%%s)(cn=%s))"
#define _F_GETHOSTDOTTEDBYNAME  "(&(objectClass=ipHost)(|(cn=%s)(cn=%s)))"
#define _F_GETHOSTDOTTEDBYNAME_SSD "(&(%%s)(|(cn=%s)(cn=%s)))"
#define _F_GETHOSTBYADDR    "(&(objectClass=ipHost)(ipHostNumber=%s))"
#define _F_GETHOSTBYADDR_SSD    "(&(%%s)(ipHostNumber=%s))"

static const char *hosts_attrs[] = {
    _H_NAME,
    _H_ADDR,
    (char *)NULL
};

/*
 * _nss_ldap_hosts2str is the data marshaling method for the hosts getXbyY
 * system call gethostbyname() and gethostbyaddr.
 * This method is called after a successful search has been performed.
 * This method will parse the search results into the file format.
 * e.g.
 *
 * 9.9.9.9 jurassic jurassic1 jurassic2
 * 10.10.10.10 puppy
 *
 */
int
_nss_ldap_hosts2str_int(int af, ldap_backend_ptr be, nss_XbyY_args_t *argp)
{
    uint_t          i;
    int         nss_result;
    int         buflen, buflen1, buflen2, len;
    int         firstimedn   = 1, first_entry;
    int         validaddress = 0, copy_cname;
    char            *cname = NULL, *h_name = NULL;
    char            *buffer = NULL;
    char            *name;
    ns_ldap_result_t    *result = be->result;
    ns_ldap_attr_t      *names;
    ns_ldap_entry_t     *entry;
    char            **ips = NULL, **dns = NULL;
    char            *first_host = NULL, *other_hosts = NULL;
    char            *buf1, *buf2;

    if (result == NULL)
        return (NSS_STR_PARSE_PARSE);
    buflen = buflen1 = buflen2 = argp->buf.buflen;

    if (argp->buf.result != NULL) {
        if ((be->buffer = calloc(1, buflen)) == NULL) {
            nss_result = NSS_STR_PARSE_PARSE;
            goto result_host2str;
        }
        buffer = be->buffer;
    } else
        buffer = argp->buf.buffer;
    if ((first_host = calloc(1, buflen1)) == NULL) {
        nss_result = NSS_STR_PARSE_PARSE;
        goto result_host2str;
    }
    if ((other_hosts = calloc(1, buflen2)) == NULL) {
        nss_result = NSS_STR_PARSE_PARSE;
        goto result_host2str;
    }

    nss_result = NSS_STR_PARSE_SUCCESS;
    (void) memset(argp->buf.buffer, 0, buflen);
    /*
     * Multiple lines return will be sepereated by newlines
     * Single line return or last line does not have newline
     * e.g.
     *
     * 8.8.8.8 hostname
     *
     * or the search for hostname h1 returns 3 entries
     *
     * 9.9.9.9 h1
     * 10.10.10.10 h1 xx
     * 20.20.20.20 h1 yyy
     *
     * str2hostent expects all name/aliases in the first entry
     * so the string is organized as
     *
     * "9.9.9.9 h1 xx yy\n10.10.10.10 \n20.20.20.20 "
     *
     * Use first_host to hold "9.9.9.9 h1 xx yy" and other_hosts to hold
     * "\n10.10.10.10 \n20.20.20.20 "
     *
     */
    buf1 = first_host;
    buf2 = other_hosts;
    first_entry = 1;
    for (entry = result->entry; entry != NULL; entry = entry->next) {
        if (firstimedn) {
            dns =  __ns_ldap_getAttr(entry, _H_DN);
            if (dns == NULL || dns[0] == NULL || strlen(dns[0])
                < 1) {
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_host2str;
            }
            /* get domain name associated with this dn */
            be->toglue = _get_domain_name(dns[0]);
            firstimedn = 0;
        }

        /* Get IP */
        ips = __ns_ldap_getAttr(entry, _H_ADDR);
        if (ips == NULL || ips[0] == NULL || strlen(ips[0]) < 1) {
            nss_result = NSS_STR_PARSE_PARSE;
            goto result_host2str;
        }
        /* Skip IPV6 address in AF_INET mode */
        if (af == AF_INET &&
            (inet_addr(_strip_quotes(ips[0])) == (in_addr_t)-1))
            continue;

        /* A valid address for either af mode */
        validaddress++;

        if (first_entry) {
            len = snprintf(buf1, buflen1, "%s", ips[0]);
            TEST_AND_ADJUST(len, buf1, buflen1, result_host2str);
        } else {
            len = snprintf(buf2, buflen2, "\n%s ", ips[0]);
            TEST_AND_ADJUST(len, buf2, buflen2, result_host2str);
        }

        /* Get host names */
        names = __ns_ldap_getAttrStruct(entry, _H_NAME);
        if (names == NULL || names->attrvalue == NULL) {
            nss_result = NSS_STR_PARSE_PARSE;
            goto result_host2str;
        }

        /* Get canonical name of each entry */
        cname = __s_api_get_canonical_name(entry, names, 1);
        if (cname == NULL || strlen(cname) < 1) {
            nss_result = NSS_STR_PARSE_PARSE;
            goto result_host2str;
        }

        /* Filter cname that's identical to h_name */
        if (first_entry) {
            h_name = cname;
            first_entry = 0;
            copy_cname = 1;
        } else if (strcasecmp(cname, h_name) != 0) {
            copy_cname = 1;
        } else
            copy_cname = 0;

        if (copy_cname) {
            /* Use the canonical name as the host name */
            if (be->toglue == NULL || DOTTEDSUBDOMAIN(cname))
                len = snprintf(buf1, buflen1, " %s", cname);
            else
                /* append domain name */
                len = snprintf(buf1, buflen1, " %s.%s", cname,
                    be->toglue);

            TEST_AND_ADJUST(len, buf1, buflen1, result_host2str);
        }

        /* Append aliases */
        for (i = 0; i < names->value_count; i++) {
            name = names->attrvalue[i];
            if (name == NULL) {
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_host2str;
            }
            /* Skip the canonical name and h_name */
            if (strcasecmp(name, cname) != 0 &&
                strcasecmp(name, h_name) != 0) {
                if (be->toglue == NULL || DOTTEDSUBDOMAIN(name))
                    len = snprintf(buf1, buflen1, " %s",
                        name);
                else
                    /* append domain name */
                    len = snprintf(buf1, buflen1, " %s.%s",
                        name, be->toglue);
                TEST_AND_ADJUST(len, buf1, buflen1,
                    result_host2str);
            }
        }
    }

    if (validaddress == 0) {
    /*
     * For AF_INET mode, it found an IPv6 address and skipped it.
     */
        nss_result = NSS_STR_PARSE_NO_ADDR;
        goto result_host2str;
    }
    /* Combine 2 strings */
    len = snprintf(buffer, buflen, "%s%s", first_host, other_hosts);
    TEST_AND_ADJUST(len, buffer, buflen, result_host2str);

    /* The front end marshaller doesn't need to copy trailing nulls */
    if (argp->buf.result != NULL)
        be->buflen = strlen(be->buffer);

result_host2str:
    if (first_host)
        free(first_host);
    if (other_hosts)
        free(other_hosts);
    if (be->toglue) {
        free(be->toglue);
        be->toglue = NULL;
    }
    (void) __ns_ldap_freeResult(&be->result);
    return (nss_result);
}

static int
_nss_ldap_hosts2str(ldap_backend_ptr be, nss_XbyY_args_t *argp) {
    return (_nss_ldap_hosts2str_int(AF_INET, be, argp));
}

/*
 * getbyname gets a struct hostent by hostname. This function constructs
 * an ldap search filter using the name invocation parameter and the
 * gethostbyname search filter defined. Once the filter is constructed,
 * we search for a matching entry and marshal the data results into
 * struct hostent for the frontend process.  Host name searches will be
 * on fully qualified host names (foo.bar.sun.com)
 */

static nss_status_t
getbyname(ldap_backend_ptr be, void *a)
{
    char        hostname[3 * MAXHOSTNAMELEN];
    char        realdomain[BUFSIZ];
    nss_XbyY_args_t *argp = (nss_XbyY_args_t *)a;
    nss_status_t    lstat;
    char        searchfilter[SEARCHFILTERLEN];
    char        userdata[SEARCHFILTERLEN];
    int     rc;

    if (_ldap_filter_name(hostname, argp->key.name, sizeof (hostname)) != 0)
        return ((nss_status_t)NSS_NOTFOUND);

    rc = snprintf(searchfilter, sizeof (searchfilter), _F_GETHOSTBYNAME,
        hostname);
    if (rc >= sizeof (searchfilter) || rc < 0)
        return ((nss_status_t)NSS_NOTFOUND);

    rc = snprintf(userdata, sizeof (userdata), _F_GETHOSTBYNAME_SSD,
        hostname);
    if (rc >= sizeof (userdata) || rc < 0)
        return ((nss_status_t)NSS_NOTFOUND);

    /* get the domain we are in */
    rc = sysinfo(SI_SRPC_DOMAIN, realdomain, BUFSIZ);
    if (rc <= 0)
        return ((nss_status_t)NSS_NOTFOUND);

    /* Is this a request for a host.domain */
    if (DOTTEDSUBDOMAIN(hostname)) {
        char    host[MAXHOSTNAMELEN];
        char    domain[MAXHOSTNAMELEN];
        char    hname[3 * MAXHOSTNAMELEN];

        /* separate host and domain.  this function */
        /* will munge hname, so use argp->keyname */
        /* from here on for original string */

        (void) strcpy(hname, hostname);

        if (chophostdomain(hname, host, domain) == -1) {
            return ((nss_status_t)NSS_NOTFOUND);
        }

        /* if domain is a proper subset of realdomain */
        /* ie. domain = "eng" and realdomain */
        /* = "eng.wiz.com", we try to lookup both" */
        /* host.domain and host */

        if (propersubdomain(realdomain, domain) == 1) {
            /* yes, it is a proper domain */
            rc = snprintf(searchfilter, sizeof (searchfilter),
                _F_GETHOSTDOTTEDBYNAME, hostname, host);
            if (rc >= sizeof (searchfilter) || rc < 0)
                return ((nss_status_t)NSS_NOTFOUND);

            rc = snprintf(userdata, sizeof (userdata),
                _F_GETHOSTDOTTEDBYNAME_SSD, hostname, host);
            if (rc >= sizeof (userdata) || rc < 0)
                return ((nss_status_t)NSS_NOTFOUND);
        } else {
            /* it is not a proper domain, so only try to look up */
            /* host.domain */
            rc = snprintf(searchfilter, sizeof (searchfilter),
                _F_GETHOSTBYNAME, hostname);
            if (rc >= sizeof (searchfilter) || rc < 0)
                return ((nss_status_t)NSS_NOTFOUND);

            rc = snprintf(userdata, sizeof (userdata),
                _F_GETHOSTBYNAME_SSD, hostname);
            if (rc >= sizeof (userdata) || rc < 0)
                return ((nss_status_t)NSS_NOTFOUND);
        }
    } else {
        rc = snprintf(searchfilter, sizeof (searchfilter),
            _F_GETHOSTBYNAME, hostname);
        if (rc >= sizeof (searchfilter) || rc < 0)
            return ((nss_status_t)NSS_NOTFOUND);

        rc = snprintf(userdata, sizeof (userdata),
            _F_GETHOSTBYNAME_SSD, hostname);
        if (rc >= sizeof (userdata) || rc < 0)
            return ((nss_status_t)NSS_NOTFOUND);
    }
    lstat = (nss_status_t)_nss_ldap_lookup(be, argp, _HOSTS, searchfilter,
        NULL, _merge_SSD_filter, userdata);
    if (lstat == (nss_status_t)NS_LDAP_SUCCESS)
        return ((nss_status_t)NSS_SUCCESS);

    argp->h_errno = __nss2herrno(lstat);
    return ((nss_status_t)lstat);
}


/*
 * getbyaddr gets a struct hostent by host address. This function
 * constructs an ldap search filter using the host address invocation
 * parameter and the gethostbyaddr search filter defined. Once the
 * filter is constructed, we search for a matching entry and marshal
 * the data results into struct hostent for the frontend process.
 *
 * extern char *inet_ntoa_r() not an advertised function from libnsl.
 * There is no man page and no prototype.
 */

static nss_status_t
getbyaddr(ldap_backend_ptr be, void *a)
{
    nss_XbyY_args_t *argp = (nss_XbyY_args_t *)a;
    struct in_addr  addr;
    char        buf[18];
    nss_status_t    lstat;
    extern char *inet_ntoa_r();
    char        searchfilter[SEARCHFILTERLEN];
    char        userdata[SEARCHFILTERLEN];
    int     ret;

    argp->h_errno = 0;
    if ((argp->key.hostaddr.type != AF_INET) ||
        (argp->key.hostaddr.len != sizeof (addr)))
        return (NSS_NOTFOUND);

    (void) memcpy(&addr, argp->key.hostaddr.addr, sizeof (addr));
    (void) inet_ntoa_r(addr, buf);

    ret = snprintf(searchfilter, sizeof (searchfilter), _F_GETHOSTBYADDR,
        buf);
    if (ret >= sizeof (searchfilter) || ret < 0)
        return ((nss_status_t)NSS_NOTFOUND);

    ret = snprintf(userdata, sizeof (userdata), _F_GETHOSTBYADDR_SSD, buf);
    if (ret >= sizeof (userdata) || ret < 0)
        return ((nss_status_t)NSS_NOTFOUND);

    lstat = (nss_status_t)_nss_ldap_lookup(be, argp, _HOSTS, searchfilter,
        NULL, _merge_SSD_filter, userdata);
    if (lstat == (nss_status_t)NS_LDAP_SUCCESS)
        return ((nss_status_t)NSS_SUCCESS);

    argp->h_errno = __nss2herrno(lstat);
    return ((nss_status_t)lstat);
}

static ldap_backend_op_t hosts_ops[] = {
    _nss_ldap_destr,
    _nss_ldap_endent,
    _nss_ldap_setent,
    _nss_ldap_getent,
    getbyname,
    getbyaddr
};


/*
 * _nss_ldap_hosts_constr is where life begins. This function calls the generic
 * ldap constructor function to define and build the abstract data types
 * required to support ldap operations.
 */

/*ARGSUSED0*/
nss_backend_t *
_nss_ldap_hosts_constr(const char *dummy1, const char *dummy2,
            const char *dummy3)
{

    return ((nss_backend_t *)_nss_ldap_constr(hosts_ops,
        sizeof (hosts_ops)/sizeof (hosts_ops[0]), _HOSTS,
        hosts_attrs, _nss_ldap_hosts2str));
}