heimdal/lib/hdb/common.c

/*
 * Copyright (c) 1997-2002 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden). 
 * 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 Institute 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 INSTITUTE 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 INSTITUTE 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 "hdb_locl.h"

RCSID("$Id$");

int
hdb_principal2key(krb5_context context, krb5_const_principal p, krb5_data *key)
{
    Principal new;
    size_t len;
    int ret;

    ret = copy_Principal(p, &new);
    if(ret) 
	return ret;
    new.name.name_type = 0;

    ASN1_MALLOC_ENCODE(Principal, key->data, key->length, &new, &len, ret);
    if (ret == 0 && key->length != len)
	krb5_abortx(context, "internal asn.1 encoder error");
    free_Principal(&new);
    return ret;
}

int
hdb_key2principal(krb5_context context, krb5_data *key, krb5_principal p)
{
    return decode_Principal(key->data, key->length, p, NULL);
}

int
hdb_entry2value(krb5_context context, const hdb_entry *ent, krb5_data *value)
{
    size_t len;
    int ret;
    
    ASN1_MALLOC_ENCODE(hdb_entry, value->data, value->length, ent, &len, ret);
    if (ret == 0 && value->length != len)
	krb5_abortx(context, "internal asn.1 encoder error");
    return ret;
}

int
hdb_value2entry(krb5_context context, krb5_data *value, hdb_entry *ent)
{
    return decode_hdb_entry(value->data, value->length, ent, NULL);
}

int
hdb_entry_alias2value(krb5_context context, 
		      const hdb_entry_alias *alias,
		      krb5_data *value)
{
    size_t len;
    int ret;
    
    ASN1_MALLOC_ENCODE(hdb_entry_alias, value->data, value->length, 
		       alias, &len, ret);
    if (ret == 0 && value->length != len)
	krb5_abortx(context, "internal asn.1 encoder error");
    return ret;
}

int
hdb_value2entry_alias(krb5_context context, krb5_data *value, 
		      hdb_entry_alias *ent)
{
    return decode_hdb_entry_alias(value->data, value->length, ent, NULL);
}

krb5_error_code
_hdb_fetch(krb5_context context, HDB *db, krb5_const_principal principal,
	   unsigned flags, hdb_entry_ex *entry)
{
    krb5_data key, value;
    int code;

    hdb_principal2key(context, principal, &key);
    code = db->hdb__get(context, db, key, &value);
    krb5_data_free(&key);
    if(code)
	return code;
    code = hdb_value2entry(context, &value, &entry->entry);
    if (code == ASN1_BAD_ID && (flags & HDB_F_CANON) == 0) {
	krb5_data_free(&value);
	return HDB_ERR_NOENTRY;
    } else if (code == ASN1_BAD_ID) {
	hdb_entry_alias alias;

	code = hdb_value2entry_alias(context, &value, &alias);
	if (code) {
	    krb5_data_free(&value);
	    return code;
	}
	hdb_principal2key(context, alias.principal, &key);
	krb5_data_free(&value);
	free_hdb_entry_alias(&alias);

	code = db->hdb__get(context, db, key, &value);
	krb5_data_free(&key);
	if (code)
	    return code;
	code = hdb_value2entry(context, &value, &entry->entry);
	if (code) {
	    krb5_data_free(&value);
	    return code;
	}
    }
    krb5_data_free(&value);
    if (db->hdb_master_key_set && (flags & HDB_F_DECRYPT)) {
	code = hdb_unseal_keys (context, db, &entry->entry);
	if (code)
	    hdb_free_entry(context, entry);
    }
    return code;
}

static krb5_error_code
hdb_remove_aliases(krb5_context context, HDB *db, krb5_data *key)
{
    const HDB_Ext_Aliases *aliases;
    krb5_error_code code;
    hdb_entry oldentry;
    krb5_data value;
    int i;

    code = db->hdb__get(context, db, *key, &value);
    if (code == HDB_ERR_NOENTRY)
	return 0;
    else if (code)
	return code;
	    
    code = hdb_value2entry(context, &value, &oldentry);
    krb5_data_free(&value);
    if (code)
	return code;

    code = hdb_entry_get_aliases(&oldentry, &aliases);
    if (code || aliases == NULL) {
	free_hdb_entry(&oldentry);
	return code;
    }
    for (i = 0; i < aliases->aliases.len; i++) {
	krb5_data akey;

	hdb_principal2key(context, &aliases->aliases.val[i], &akey);
	code = db->hdb__del(context, db, akey);
	krb5_data_free(&akey);
	if (code) {
	    free_hdb_entry(&oldentry);
	    return code;
	}
    }
    free_hdb_entry(&oldentry);
    return 0;
}

static krb5_error_code
hdb_add_aliases(krb5_context context, HDB *db, 
		unsigned flags, hdb_entry_ex *entry)
{
    const HDB_Ext_Aliases *aliases;
    krb5_error_code code;
    krb5_data key, value;
    int i;
    
    code = hdb_entry_get_aliases(&entry->entry, &aliases);
    if (code || aliases == NULL)
	return code;
    
    for (i = 0; i < aliases->aliases.len; i++) {
	hdb_entry_alias entryalias;
	entryalias.principal = entry->entry.principal;
	
	hdb_principal2key(context, &aliases->aliases.val[i], &key);
	code = hdb_entry_alias2value(context, &entryalias, &value);
	if (code) {
	    krb5_data_free(&key);
	    return code;
	}
	code = db->hdb__put(context, db, flags, key, value);
	krb5_data_free(&key);
	krb5_data_free(&value);
	if (code)
	    return code;
    }
    return 0;
}

static krb5_error_code
hdb_check_aliases(krb5_context context, HDB *db, hdb_entry_ex *entry)
{
    const HDB_Ext_Aliases *aliases;
    int code, i;

    /* check if new aliases already is used */

    code = hdb_entry_get_aliases(&entry->entry, &aliases);
    if (code)
	return code;

    for (i = 0; aliases && i < aliases->aliases.len; i++) {
	hdb_entry_alias alias;
	krb5_data akey, value;

	hdb_principal2key(context, &aliases->aliases.val[i], &akey);
	code = db->hdb__get(context, db, akey, &value);
	krb5_data_free(&akey);
	if (code == HDB_ERR_NOENTRY)
	    continue;
	else if (code)
	    return code;

	code = hdb_value2entry_alias(context, &value, &alias);
	krb5_data_free(&value);

	if (code == ASN1_BAD_ID)
	    return HDB_ERR_EXISTS;
	else if (code)
	    return code;

	code = krb5_principal_compare(context, alias.principal,
				      entry->entry.principal);
	free_hdb_entry_alias(&alias);
	if (code == 0)
	    return HDB_ERR_EXISTS;
    }
    return 0;
}

krb5_error_code
_hdb_store(krb5_context context, HDB *db, unsigned flags, hdb_entry_ex *entry)
{
    krb5_data key, value;
    int code;

    /* check if new aliases already is used */
    code = hdb_check_aliases(context, db, entry);
    if (code)
	return code;

    if(entry->entry.generation == NULL) {
	struct timeval t;
	entry->entry.generation = malloc(sizeof(*entry->entry.generation));
	if(entry->entry.generation == NULL) {
	    krb5_set_error_string(context, "malloc: out of memory");
	    return ENOMEM;
	}
	gettimeofday(&t, NULL);
	entry->entry.generation->time = t.tv_sec;
	entry->entry.generation->usec = t.tv_usec;
	entry->entry.generation->gen = 0;
    } else
	entry->entry.generation->gen++;

    code = hdb_seal_keys(context, db, &entry->entry);
    if (code)
	return code;

    hdb_principal2key(context, entry->entry.principal, &key);

    /* remove aliases */
    code = hdb_remove_aliases(context, db, &key);
    if (code) {
	krb5_data_free(&key);
	return code;
    }
    hdb_entry2value(context, &entry->entry, &value);
    code = db->hdb__put(context, db, flags & HDB_F_REPLACE, key, value);
    krb5_data_free(&value);
    krb5_data_free(&key);
    if (code)
	return code;

    code = hdb_add_aliases(context, db, flags, entry);

    return code;
}

krb5_error_code
_hdb_remove(krb5_context context, HDB *db, krb5_const_principal principal)
{
    krb5_data key;
    int code;

    hdb_principal2key(context, principal, &key);

    code = hdb_remove_aliases(context, db, &key);
    if (code) {
	krb5_data_free(&key);
	return code;
    }
    code = db->hdb__del(context, db, key);
    krb5_data_free(&key);
    return code;
}