root/usr/src/lib/nsswitch/ldap/common/getkeyent.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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <pwd.h>
#include <ctype.h>
#include "ldap_common.h"

/* publickey attributes filters */
#define _KEY_CN                 "cn"
#define _KEY_NISPUBLICKEY       "nisPublickey"
#define _KEY_NISSECRETKEY       "nisSecretkey"
#define _KEY_UIDNUMBER          "uidnumber"

#define _F_GETKEY_USER          "(&(objectClass=nisKeyObject)(uidNumber=%s))"
#define _F_GETKEY_USER_SSD      "(&(%%s)(uidNumber=%s))"
#define _F_GETKEY_HOST          "(&(objectClass=nisKeyObject)(cn=%s))"
#define _F_GETKEY_HOST_SSD      "(&(%%s)(cn=%s))"

static const char *keys_attrs[] = {
        _KEY_NISPUBLICKEY,
        _KEY_NISSECRETKEY,
        (char *)NULL
};


/*
 * _nss_ldap_key2str is the data marshaling method for the publickey getXbyY
 * (e.g., getpublickey() and getsecretkey()) backend processes. This method
 * is called after a successful ldap search has been performed. This method
 * will parse the ldap search values into "public:secret" file format.
 *
 * c3d91f44568fbbefada50d336d9bd67b16e7016f987bb607:
 * 7675cd9b8753b5db09dabf12da759c2bd1331c927bb322861fffb54be13f55e9
 *
 * (All in one line)
 *
 * Publickey does not have a front end marshaller so db_type is set
 * for special handling.
 */

static int
_nss_ldap_key2str(ldap_backend_ptr be, nss_XbyY_args_t *argp)
{
        int             nss_result;
        char            *keytype = (char *)argp->key.pkey.keytype;
        int             keytypelen = strlen(keytype);
        int             len;
        int             buflen = argp->buf.buflen;
        char            *buffer, *pkey, *skey;
        ns_ldap_result_t        *result = be->result;
        char            **pkey_array, **skey_array;

        if (result == NULL || keytype == NULL) {
                nss_result = NSS_STR_PARSE_ERANGE;
                goto result_key2str;
        }
        nss_result = NSS_STR_PARSE_SUCCESS;
        (void) memset(argp->buf.buffer, 0, buflen);
        /* get the publickey */
        pkey_array = __ns_ldap_getAttr(result->entry, _KEY_NISPUBLICKEY);
        if (pkey_array == NULL) {
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_key2str;
        }
        while (*pkey_array) {
                if (strncasecmp(*pkey_array, keytype, keytypelen) == 0)
                        break;
                pkey_array++;
        }
        if (*pkey_array == NULL) {
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_key2str;
        }
        pkey = *pkey_array + keytypelen;

        /* get the secretkey */
        skey_array = __ns_ldap_getAttr(result->entry, _KEY_NISSECRETKEY);
        if (skey_array == NULL) {
                /*
                 * if we got this far, it's possible that the secret
                 * key is actually missing or no permission to read it.
                 * For the current implementation, we assume that the
                 * clients have read permission to the secret key.  So,
                 * the only possibility of reaching this here is due to
                 * missing secret key.
                 */
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_key2str;
        }
        while (*skey_array) {
                if (strncasecmp(*skey_array, keytype, keytypelen) == 0)
                        break;
                skey_array++;
        }
        if (*skey_array == NULL) {
                nss_result = NSS_STR_PARSE_PARSE;
                goto result_key2str;
        }
        skey = *skey_array + keytypelen;

        /* 2 = 1 ':' + 1 '\0' */
        len = strlen(pkey) + strlen(skey) + 2;
        if (len > buflen) {
                nss_result = NSS_STR_PARSE_ERANGE;
                goto result_key2str;
        }
        /*
         * publickey does not have a frontend marshaller.
         * copy the result to buf.buffer directly
         */
        buffer = argp->buf.buffer;

        (void) snprintf(buffer, len, "%s:%s", pkey, skey);

        be->db_type = NSS_LDAP_DB_PUBLICKEY;

result_key2str:

        (void) __ns_ldap_freeResult(&be->result);
        return ((int)nss_result);
}


/*
 * getkeys gets both the public and secret keys from publickey entry by either
 * uid name or host name. This function constructs an ldap search filter using
 * the name invocation parameter and the getpwnam search filter defined. Once
 * the filter is constructed, we search for a matching entry and marshal the
 * data results into struct passwd for the frontend process. The function
 * _nss_ldap_key2ent performs the data marshaling.
 * The lookups will be done using the proxy credential.  We don't want to use
 * the user's credential for lookup at this point because we don't have any
 * secure transport.
 */

static nss_status_t
getkeys(ldap_backend_ptr be, void *a)
{
        nss_XbyY_args_t *argp = (nss_XbyY_args_t *)a;
        char    searchfilter[SEARCHFILTERLEN];
        char    userdata[SEARCHFILTERLEN];
        char    netname[SEARCHFILTERLEN];
        char    *name, *domain, *p;
        nss_status_t    rc;
        int     ret;

        /*
         * We need to break it down to find if this is a netname for host
         * or user.  We'll pass the domain as is to the LDAP call.
         */
        if (_ldap_filter_name(netname, argp->key.pkey.name, sizeof (netname))
                        != 0)
                return ((nss_status_t)NSS_NOTFOUND);

        domain = strchr(netname, '@');
        if (!domain)
                return ((nss_status_t)NSS_NOTFOUND);

        *domain++ = '\0';
        if ((p = strchr(netname, '.')) == NULL)
                return ((nss_status_t)NSS_NOTFOUND);

        name = ++p;
        if (isdigit(*name)) {
                /* user keys lookup */
                ret = snprintf(searchfilter, sizeof (searchfilter),
                    _F_GETKEY_USER, name);
                if (ret >= sizeof (searchfilter) || ret < 0)
                        return ((nss_status_t)NSS_NOTFOUND);

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

                rc = (nss_status_t)_nss_ldap_lookup(be, argp,
                                _PASSWD, searchfilter, domain,
                                _merge_SSD_filter, userdata);
        } else {
                /* host keys lookup */
                ret = snprintf(searchfilter, sizeof (searchfilter),
                    _F_GETKEY_HOST, name);
                if (ret >= sizeof (searchfilter) || ret < 0)
                        return ((nss_status_t)NSS_NOTFOUND);

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

                rc = (nss_status_t)_nss_ldap_lookup(be, argp,
                                _HOSTS, searchfilter, domain,
                                _merge_SSD_filter, userdata);
        }
        return (rc);
}


static ldap_backend_op_t keys_ops[] = {
        _nss_ldap_destr,
        0,
        0,
        0,
        getkeys
};


/*
 * _nss_ldap_publickey_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_publickey_constr(const char *dummy1, const char *dummy2,
                        const char *dummy3)
{

        return ((nss_backend_t *)_nss_ldap_constr(keys_ops,
                    sizeof (keys_ops)/sizeof (keys_ops[0]),
                    _PUBLICKEY, keys_attrs, _nss_ldap_key2str));
}