creds.c

/*
 * Copyright (c) 1997 - 2005 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 "krb5_locl.h"

/**
 * Free content of krb5_creds.
 *
 * @param context Kerberos 5 context.
 * @param c krb5_creds to free.
 *
 * @return Returns 0 to indicate success. Otherwise an kerberos et
 * error code is returned, see krb5_get_error_message().
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_free_cred_contents (krb5_context context, krb5_creds *c)
{
    krb5_free_principal (context, c->client);
    c->client = NULL;
    krb5_free_principal (context, c->server);
    c->server = NULL;
    krb5_free_keyblock_contents (context, &c->session);
    krb5_data_free (&c->ticket);
    krb5_data_free (&c->second_ticket);
    free_AuthorizationData (&c->authdata);
    krb5_free_addresses (context, &c->addresses);
    memset(c, 0, sizeof(*c));
    return 0;
}

/**
 * Copy content of krb5_creds.
 *
 * @param context Kerberos 5 context.
 * @param incred source credential
 * @param c destination credential, free with krb5_free_cred_contents().
 *
 * @return Returns 0 to indicate success. Otherwise an kerberos et
 * error code is returned, see krb5_get_error_message().
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_copy_creds_contents (krb5_context context,
			  const krb5_creds *incred,
			  krb5_creds *c)
{
    krb5_error_code ret;

    memset(c, 0, sizeof(*c));
    ret = krb5_copy_principal (context, incred->client, &c->client);
    if (ret)
	goto fail;
    ret = krb5_copy_principal (context, incred->server, &c->server);
    if (ret)
	goto fail;
    ret = krb5_copy_keyblock_contents (context, &incred->session, &c->session);
    if (ret)
	goto fail;
    c->times = incred->times;
    ret = krb5_data_copy (&c->ticket,
			  incred->ticket.data,
			  incred->ticket.length);
    if (ret)
	goto fail;
    ret = krb5_data_copy (&c->second_ticket,
			  incred->second_ticket.data,
			  incred->second_ticket.length);
    if (ret)
	goto fail;
    ret = copy_AuthorizationData(&incred->authdata, &c->authdata);
    if (ret)
	goto fail;
    ret = krb5_copy_addresses (context,
			       &incred->addresses,
			       &c->addresses);
    if (ret)
	goto fail;
    c->flags = incred->flags;
    return 0;

fail:
    krb5_free_cred_contents (context, c);
    return ret;
}

/**
 * Copy krb5_creds.
 *
 * @param context Kerberos 5 context.
 * @param incred source credential
 * @param outcred destination credential, free with krb5_free_creds().
 *
 * @return Returns 0 to indicate success. Otherwise an kerberos et
 * error code is returned, see krb5_get_error_message().
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_copy_creds (krb5_context context,
		 const krb5_creds *incred,
		 krb5_creds **outcred)
{
    krb5_creds *c;

    c = malloc (sizeof (*c));
    if (c == NULL) {
	krb5_set_error_message (context, ENOMEM,
				N_("malloc: out of memory", ""));
	return ENOMEM;
    }
    memset (c, 0, sizeof(*c));
    *outcred = c;
    return krb5_copy_creds_contents (context, incred, c);
}

/**
 * Free krb5_creds.
 *
 * @param context Kerberos 5 context.
 * @param c krb5_creds to free.
 *
 * @return Returns 0 to indicate success. Otherwise an kerberos et
 * error code is returned, see krb5_get_error_message().
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_free_creds (krb5_context context, krb5_creds *c)
{
    krb5_free_cred_contents (context, c);
    free (c);
    return 0;
}

/* XXX this do not belong here */
static krb5_boolean
krb5_times_equal(const krb5_times *a, const krb5_times *b)
{
    return a->starttime == b->starttime &&
	a->authtime == b->authtime &&
	a->endtime == b->endtime &&
	a->renew_till == b->renew_till;
}

/**
 * Return TRUE if `mcreds' and `creds' are equal (`whichfields'
 * determines what equal means).
 *
 *
 * The following flags, set in whichfields affects the comparison:
 * - KRB5_TC_MATCH_SRV_NAMEONLY Consider all realms equal when comparing the service principal.
 * - KRB5_TC_MATCH_KEYTYPE Compare enctypes.
 * - KRB5_TC_MATCH_FLAGS_EXACT Make sure that the ticket flags are identical.
 * - KRB5_TC_MATCH_FLAGS Make sure that all ticket flags set in mcreds are also present in creds .
 * - KRB5_TC_MATCH_TIMES_EXACT Compares the ticket times exactly.
 * - KRB5_TC_MATCH_TIMES Compares only the expiration times of the creds.
 * - KRB5_TC_MATCH_AUTHDATA Compares the authdata fields.
 * - KRB5_TC_MATCH_2ND_TKT Compares the second tickets (used by user-to-user authentication).
 * - KRB5_TC_MATCH_IS_SKEY Compares the existance of the second ticket.
 *
 * @param context Kerberos 5 context.
 * @param whichfields which fields to compare.
 * @param mcreds cred to compare with.
 * @param creds cred to compare with.
 *
 * @return return TRUE if mcred and creds are equal, FALSE if not.
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_compare_creds(krb5_context context, krb5_flags whichfields,
		   const krb5_creds * mcreds, const krb5_creds * creds)
{
    krb5_boolean match = TRUE;

    if (match && mcreds->server) {
	if (whichfields & (KRB5_TC_DONT_MATCH_REALM | KRB5_TC_MATCH_SRV_NAMEONLY))
	    match = krb5_principal_compare_any_realm (context, mcreds->server,
						      creds->server);
	else
	    match = krb5_principal_compare (context, mcreds->server,
					    creds->server);
    }

    if (match && mcreds->client) {
	if(whichfields & KRB5_TC_DONT_MATCH_REALM)
	    match = krb5_principal_compare_any_realm (context, mcreds->client,
						      creds->client);
	else
	    match = krb5_principal_compare (context, mcreds->client,
					    creds->client);
    }

    if (match && (whichfields & KRB5_TC_MATCH_KEYTYPE))
        match = mcreds->session.keytype == creds->session.keytype;

    if (match && (whichfields & KRB5_TC_MATCH_FLAGS_EXACT))
	match = mcreds->flags.i == creds->flags.i;

    if (match && (whichfields & KRB5_TC_MATCH_FLAGS))
	match = (creds->flags.i & mcreds->flags.i) == mcreds->flags.i;

    if (match && (whichfields & KRB5_TC_MATCH_TIMES_EXACT))
	match = krb5_times_equal(&mcreds->times, &creds->times);

    if (match && (whichfields & KRB5_TC_MATCH_TIMES))
	/* compare only expiration times */
	match = (mcreds->times.renew_till <= creds->times.renew_till) &&
	    (mcreds->times.endtime <= creds->times.endtime);

    if (match && (whichfields & KRB5_TC_MATCH_AUTHDATA)) {
	unsigned int i;
	if(mcreds->authdata.len != creds->authdata.len)
	    match = FALSE;
	else
	    for(i = 0; match && i < mcreds->authdata.len; i++)
		match = (mcreds->authdata.val[i].ad_type ==
			 creds->authdata.val[i].ad_type) &&
		    (krb5_data_cmp(&mcreds->authdata.val[i].ad_data,
				   &creds->authdata.val[i].ad_data) == 0);
    }
    if (match && (whichfields & KRB5_TC_MATCH_2ND_TKT))
	match = (krb5_data_cmp(&mcreds->second_ticket, &creds->second_ticket) == 0);

    if (match && (whichfields & KRB5_TC_MATCH_IS_SKEY))
	match = ((mcreds->second_ticket.length == 0) ==
		 (creds->second_ticket.length == 0));

    return match;
}

/**
 * Returns the ticket flags for the credentials in creds.
 * See also krb5_ticket_get_flags().
 *
 * @param creds credential to get ticket flags from
 *
 * @return ticket flags
 *
 * @ingroup krb5
 */

KRB5_LIB_FUNCTION unsigned long KRB5_LIB_CALL
krb5_creds_get_ticket_flags(krb5_creds *creds)
{
    return TicketFlags2int(creds->flags.b);
}