freebsd-dev/crypto/heimdal/lib/krb5/rd_cred.c
2008-05-07 13:39:42 +00:00

341 lines
9.3 KiB
C

/*
* Copyright (c) 1997 - 2007 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>
RCSID("$Id: rd_cred.c 20304 2007-04-11 11:15:05Z lha $");
static krb5_error_code
compare_addrs(krb5_context context,
krb5_address *a,
krb5_address *b,
const char *message)
{
char a_str[64], b_str[64];
size_t len;
if(krb5_address_compare (context, a, b))
return 0;
krb5_print_address (a, a_str, sizeof(a_str), &len);
krb5_print_address (b, b_str, sizeof(b_str), &len);
krb5_set_error_string(context, "%s: %s != %s", message, b_str, a_str);
return KRB5KRB_AP_ERR_BADADDR;
}
krb5_error_code KRB5_LIB_FUNCTION
krb5_rd_cred(krb5_context context,
krb5_auth_context auth_context,
krb5_data *in_data,
krb5_creds ***ret_creds,
krb5_replay_data *outdata)
{
krb5_error_code ret;
size_t len;
KRB_CRED cred;
EncKrbCredPart enc_krb_cred_part;
krb5_data enc_krb_cred_part_data;
krb5_crypto crypto;
int i;
memset(&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
if ((auth_context->flags &
(KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
outdata == NULL)
return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */
*ret_creds = NULL;
ret = decode_KRB_CRED(in_data->data, in_data->length,
&cred, &len);
if(ret) {
krb5_clear_error_string(context);
return ret;
}
if (cred.pvno != 5) {
ret = KRB5KRB_AP_ERR_BADVERSION;
krb5_clear_error_string (context);
goto out;
}
if (cred.msg_type != krb_cred) {
ret = KRB5KRB_AP_ERR_MSG_TYPE;
krb5_clear_error_string (context);
goto out;
}
if (cred.enc_part.etype == ETYPE_NULL) {
/* DK: MIT GSS-API Compatibility */
enc_krb_cred_part_data.length = cred.enc_part.cipher.length;
enc_krb_cred_part_data.data = cred.enc_part.cipher.data;
} else {
/* Try both subkey and session key.
*
* RFC4120 claims we should use the session key, but Heimdal
* before 0.8 used the remote subkey if it was send in the
* auth_context.
*/
if (auth_context->remote_subkey) {
ret = krb5_crypto_init(context, auth_context->remote_subkey,
0, &crypto);
if (ret)
goto out;
ret = krb5_decrypt_EncryptedData(context,
crypto,
KRB5_KU_KRB_CRED,
&cred.enc_part,
&enc_krb_cred_part_data);
krb5_crypto_destroy(context, crypto);
}
/*
* If there was not subkey, or we failed using subkey,
* retry using the session key
*/
if (auth_context->remote_subkey == NULL || ret == KRB5KRB_AP_ERR_BAD_INTEGRITY)
{
ret = krb5_crypto_init(context, auth_context->keyblock,
0, &crypto);
if (ret)
goto out;
ret = krb5_decrypt_EncryptedData(context,
crypto,
KRB5_KU_KRB_CRED,
&cred.enc_part,
&enc_krb_cred_part_data);
krb5_crypto_destroy(context, crypto);
}
if (ret)
goto out;
}
ret = krb5_decode_EncKrbCredPart (context,
enc_krb_cred_part_data.data,
enc_krb_cred_part_data.length,
&enc_krb_cred_part,
&len);
if (enc_krb_cred_part_data.data != cred.enc_part.cipher.data)
krb5_data_free(&enc_krb_cred_part_data);
if (ret)
goto out;
/* check sender address */
if (enc_krb_cred_part.s_address
&& auth_context->remote_address
&& auth_context->remote_port) {
krb5_address *a;
ret = krb5_make_addrport (context, &a,
auth_context->remote_address,
auth_context->remote_port);
if (ret)
goto out;
ret = compare_addrs(context, a, enc_krb_cred_part.s_address,
"sender address is wrong in received creds");
krb5_free_address(context, a);
free(a);
if(ret)
goto out;
}
/* check receiver address */
if (enc_krb_cred_part.r_address
&& auth_context->local_address) {
if(auth_context->local_port &&
enc_krb_cred_part.r_address->addr_type == KRB5_ADDRESS_ADDRPORT) {
krb5_address *a;
ret = krb5_make_addrport (context, &a,
auth_context->local_address,
auth_context->local_port);
if (ret)
goto out;
ret = compare_addrs(context, a, enc_krb_cred_part.r_address,
"receiver address is wrong in received creds");
krb5_free_address(context, a);
free(a);
if(ret)
goto out;
} else {
ret = compare_addrs(context, auth_context->local_address,
enc_krb_cred_part.r_address,
"receiver address is wrong in received creds");
if(ret)
goto out;
}
}
/* check timestamp */
if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
krb5_timestamp sec;
krb5_timeofday (context, &sec);
if (enc_krb_cred_part.timestamp == NULL ||
enc_krb_cred_part.usec == NULL ||
abs(*enc_krb_cred_part.timestamp - sec)
> context->max_skew) {
krb5_clear_error_string (context);
ret = KRB5KRB_AP_ERR_SKEW;
goto out;
}
}
if ((auth_context->flags &
(KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE))) {
/* if these fields are not present in the cred-part, silently
return zero */
memset(outdata, 0, sizeof(*outdata));
if(enc_krb_cred_part.timestamp)
outdata->timestamp = *enc_krb_cred_part.timestamp;
if(enc_krb_cred_part.usec)
outdata->usec = *enc_krb_cred_part.usec;
if(enc_krb_cred_part.nonce)
outdata->seq = *enc_krb_cred_part.nonce;
}
/* Convert to NULL terminated list of creds */
*ret_creds = calloc(enc_krb_cred_part.ticket_info.len + 1,
sizeof(**ret_creds));
if (*ret_creds == NULL) {
ret = ENOMEM;
krb5_set_error_string (context, "malloc: out of memory");
goto out;
}
for (i = 0; i < enc_krb_cred_part.ticket_info.len; ++i) {
KrbCredInfo *kci = &enc_krb_cred_part.ticket_info.val[i];
krb5_creds *creds;
creds = calloc(1, sizeof(*creds));
if(creds == NULL) {
ret = ENOMEM;
krb5_set_error_string (context, "malloc: out of memory");
goto out;
}
ASN1_MALLOC_ENCODE(Ticket, creds->ticket.data, creds->ticket.length,
&cred.tickets.val[i], &len, ret);
if (ret) {
free(creds);
goto out;
}
if(creds->ticket.length != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
copy_EncryptionKey (&kci->key, &creds->session);
if (kci->prealm && kci->pname)
_krb5_principalname2krb5_principal (context,
&creds->client,
*kci->pname,
*kci->prealm);
if (kci->flags)
creds->flags.b = *kci->flags;
if (kci->authtime)
creds->times.authtime = *kci->authtime;
if (kci->starttime)
creds->times.starttime = *kci->starttime;
if (kci->endtime)
creds->times.endtime = *kci->endtime;
if (kci->renew_till)
creds->times.renew_till = *kci->renew_till;
if (kci->srealm && kci->sname)
_krb5_principalname2krb5_principal (context,
&creds->server,
*kci->sname,
*kci->srealm);
if (kci->caddr)
krb5_copy_addresses (context,
kci->caddr,
&creds->addresses);
(*ret_creds)[i] = creds;
}
(*ret_creds)[i] = NULL;
free_KRB_CRED (&cred);
free_EncKrbCredPart(&enc_krb_cred_part);
return 0;
out:
free_EncKrbCredPart(&enc_krb_cred_part);
free_KRB_CRED (&cred);
if(*ret_creds) {
for(i = 0; (*ret_creds)[i]; i++)
krb5_free_creds(context, (*ret_creds)[i]);
free(*ret_creds);
*ret_creds = NULL;
}
return ret;
}
krb5_error_code KRB5_LIB_FUNCTION
krb5_rd_cred2 (krb5_context context,
krb5_auth_context auth_context,
krb5_ccache ccache,
krb5_data *in_data)
{
krb5_error_code ret;
krb5_creds **creds;
int i;
ret = krb5_rd_cred(context, auth_context, in_data, &creds, NULL);
if(ret)
return ret;
/* Store the creds in the ccache */
for(i = 0; creds && creds[i]; i++) {
krb5_cc_store_cred(context, ccache, creds[i]);
krb5_free_creds(context, creds[i]);
}
free(creds);
return 0;
}