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/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <string.h>
#include "k5-int.h"
#include <kadm5/admin.h>
#include <client_internal.h>
#include "auth_con.h"
#include <locale.h>
krb5_error_code
krb5int_mk_chpw_req(
krb5_context context,
krb5_auth_context auth_context,
krb5_data *ap_req,
char *passwd,
krb5_data *packet)
{
krb5_error_code ret = 0;
krb5_data clearpw;
krb5_data cipherpw;
krb5_replay_data replay;
char *ptr;
cipherpw.data = NULL;
if ((ret = krb5_auth_con_setflags(context, auth_context,
KRB5_AUTH_CONTEXT_DO_SEQUENCE)))
goto cleanup;
clearpw.length = strlen(passwd);
clearpw.data = passwd;
if ((ret = krb5_mk_priv(context, auth_context,
&clearpw, &cipherpw, &replay)))
goto cleanup;
packet->length = 6 + ap_req->length + cipherpw.length;
packet->data = (char *) malloc(packet->length);
if (packet->data == NULL)
{
ret = ENOMEM;
goto cleanup;
}
ptr = packet->data;
/* length */
*ptr++ = (packet->length>> 8) & 0xff;
*ptr++ = packet->length & 0xff;
/* version == 0x0001 big-endian
* NOTE: when MS and MIT start supporting the latest
* version of the passwd change protocol (v2),
* this value will change to 2.
*/
*ptr++ = 0;
*ptr++ = 1;
/* ap_req length, big-endian */
*ptr++ = (ap_req->length>>8) & 0xff;
*ptr++ = ap_req->length & 0xff;
/* ap-req data */
memcpy(ptr, ap_req->data, ap_req->length);
ptr += ap_req->length;
/* krb-priv of password */
memcpy(ptr, cipherpw.data, cipherpw.length);
cleanup:
if(cipherpw.data != NULL) /* allocated by krb5_mk_priv */
free(cipherpw.data);
return(ret);
}
krb5_error_code
krb5int_rd_chpw_rep(krb5_context context, krb5_auth_context auth_context, krb5_data *packet, int *result_code, krb5_data *result_data)
{
char *ptr;
int plen, vno;
krb5_data ap_rep;
krb5_ap_rep_enc_part *ap_rep_enc;
krb5_error_code ret;
krb5_data cipherresult;
krb5_data clearresult;
krb5_error *krberror;
krb5_replay_data replay;
krb5_keyblock *tmp;
int local_result_code;
if (packet->length < 4)
/* either this, or the server is printing bad messages,
or the caller passed in garbage */
return(KRB5KRB_AP_ERR_MODIFIED);
ptr = packet->data;
/* verify length */
plen = (*ptr++ & 0xff);
plen = (plen<<8) | (*ptr++ & 0xff);
if (plen != packet->length)
{
/*
* MS KDCs *may* send back a KRB_ERROR. Although
* not 100% correct via RFC3244, it's something
* we can workaround here.
*/
if (krb5_is_krb_error(packet)) {
if ((ret = krb5_rd_error(context, packet, &krberror)))
return(ret);
if (krberror->e_data.data == NULL) {
ret = ERROR_TABLE_BASE_krb5 + (krb5_error_code) krberror->error;
krb5_free_error(context, krberror);
return (ret);
}
}
else
{
return(KRB5KRB_AP_ERR_MODIFIED);
}
}
/* verify version number */
vno = (*ptr++ & 0xff);
vno = (vno<<8) | (*ptr++ & 0xff);
/*
* when the servers update to v2 of the protocol,
* "2" will be a valid version number here
*/
if (vno != 1 && vno != 2)
return (KRB5KDC_ERR_BAD_PVNO);
/* read, check ap-rep length */
ap_rep.length = (*ptr++ & 0xff);
ap_rep.length = (ap_rep.length<<8) | (*ptr++ & 0xff);
if (ptr + ap_rep.length >= packet->data + packet->length)
return(KRB5KRB_AP_ERR_MODIFIED);
if (ap_rep.length) {
/* verify ap_rep */
ap_rep.data = ptr;
ptr += ap_rep.length;
/*
* Save send_subkey to later smash recv_subkey.
*/
ret = krb5_auth_con_getsendsubkey(context, auth_context, &tmp);
if (ret)
return ret;
ret = krb5_rd_rep(context, auth_context, &ap_rep, &ap_rep_enc);
if (ret) {
krb5_free_keyblock(context, tmp);
return(ret);
}
krb5_free_ap_rep_enc_part(context, ap_rep_enc);
/* extract and decrypt the result */
cipherresult.data = ptr;
cipherresult.length = (packet->data + packet->length) - ptr;
/*
* Smash recv_subkey to be send_subkey, per spec.
*/
ret = krb5_auth_con_setrecvsubkey(context, auth_context, tmp);
krb5_free_keyblock(context, tmp);
if (ret)
return ret;
ret = krb5_rd_priv(context, auth_context, &cipherresult, &clearresult,
&replay);
if (ret)
return(ret);
} else {
cipherresult.data = ptr;
cipherresult.length = (packet->data + packet->length) - ptr;
if ((ret = krb5_rd_error(context, &cipherresult, &krberror)))
return(ret);
clearresult = krberror->e_data;
}
if (clearresult.length < 2) {
ret = KRB5KRB_AP_ERR_MODIFIED;
goto cleanup;
}
ptr = clearresult.data;
local_result_code = (*ptr++ & 0xff);
local_result_code = (local_result_code<<8) | (*ptr++ & 0xff);
if (result_code)
*result_code = local_result_code;
/*
* Make sure the result code is in range for this
* protocol.
*/
if ((local_result_code < KRB5_KPASSWD_SUCCESS) ||
(local_result_code > KRB5_KPASSWD_ETYPE_NOSUPP)) {
ret = KRB5KRB_AP_ERR_MODIFIED;
goto cleanup;
}
/* all success replies should be authenticated/encrypted */
if ((ap_rep.length == 0) && (local_result_code == KRB5_KPASSWD_SUCCESS)) {
ret = KRB5KRB_AP_ERR_MODIFIED;
goto cleanup;
}
result_data->length = (clearresult.data + clearresult.length) - ptr;
if (result_data->length) {
result_data->data = (char *) malloc(result_data->length);
if (result_data->data == NULL) {
ret = ENOMEM;
goto cleanup;
}
memcpy(result_data->data, ptr, result_data->length);
} else {
result_data->data = NULL;
}
ret = 0;
cleanup:
if (ap_rep.length) {
krb5_xfree(clearresult.data);
} else {
krb5_free_error(context, krberror);
}
return(ret);
}
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