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/*
Unix SMB/CIFS implementation.
dcerpc schannel operations
Copyright (C) Andrew Tridgell 2004
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
#include "librpc/gen_ndr/ndr_schannel.h"
#include "auth/auth.h"
/*
get a schannel key using a netlogon challenge on a secondary pipe
*/
static NTSTATUS dcerpc_schannel_key(TALLOC_CTX *tmp_ctx,
struct dcerpc_pipe *p,
struct cli_credentials *credentials,
int chan_type)
{
NTSTATUS status;
struct dcerpc_binding *b;
struct dcerpc_pipe *p2;
struct netr_ServerReqChallenge r;
struct netr_ServerAuthenticate2 a;
struct netr_Credential credentials1, credentials2, credentials3;
struct samr_Password mach_pwd;
uint32_t negotiate_flags;
struct creds_CredentialState *creds;
creds = talloc(tmp_ctx, struct creds_CredentialState);
if (!creds) {
return NT_STATUS_NO_MEMORY;
}
if (p->conn->flags & DCERPC_SCHANNEL_128) {
negotiate_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
} else {
negotiate_flags = NETLOGON_NEG_AUTH2_FLAGS;
}
/*
step 1 - establish a netlogon connection, with no authentication
*/
/* Find the original binding string */
status = dcerpc_parse_binding(tmp_ctx, p->conn->binding_string, &b);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0,("Failed to parse dcerpc binding '%s'\n", p->conn->binding_string));
return status;
}
/* Make binding string for netlogon, not the other pipe */
status = dcerpc_epm_map_binding(tmp_ctx, b, DCERPC_NETLOGON_UUID, DCERPC_NETLOGON_VERSION);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0,("Failed to map DCERPC/TCP NCACN_NP pipe for '%s' - %s\n",
DCERPC_NETLOGON_UUID, nt_errstr(status)));
return status;
}
status = dcerpc_secondary_connection(p, &p2, b);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
status = dcerpc_bind_auth_none(p2, DCERPC_NETLOGON_UUID,
DCERPC_NETLOGON_VERSION);
if (!NT_STATUS_IS_OK(status)) {
talloc_free(p2);
return status;
}
/*
step 2 - request a netlogon challenge
*/
r.in.server_name = talloc_asprintf(tmp_ctx, "\\\\%s", dcerpc_server_name(p));
r.in.computer_name = cli_credentials_get_workstation(credentials);
r.in.credentials = &credentials1;
r.out.credentials = &credentials2;
generate_random_buffer(credentials1.data, sizeof(credentials1.data));
status = dcerpc_netr_ServerReqChallenge(p2, tmp_ctx, &r);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
/*
step 3 - authenticate on the netlogon pipe
*/
E_md4hash(cli_credentials_get_password(credentials), mach_pwd.hash);
creds_client_init(creds, &credentials1, &credentials2,
&mach_pwd, &credentials3,
negotiate_flags);
a.in.server_name = r.in.server_name;
a.in.account_name = cli_credentials_get_username(credentials);
a.in.secure_channel_type = chan_type;
a.in.computer_name = cli_credentials_get_workstation(credentials);
a.in.negotiate_flags = &negotiate_flags;
a.out.negotiate_flags = &negotiate_flags;
a.in.credentials = &credentials3;
a.out.credentials = &credentials3;
status = dcerpc_netr_ServerAuthenticate2(p2, tmp_ctx, &a);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
if (!creds_client_check(creds, a.out.credentials)) {
return NT_STATUS_UNSUCCESSFUL;
}
cli_credentials_set_netlogon_creds(credentials, creds);
/*
the schannel session key is now in creds.session_key
we no longer need the netlogon pipe open
*/
talloc_free(p2);
return NT_STATUS_OK;
}
NTSTATUS dcerpc_bind_auth_schannel(TALLOC_CTX *tmp_ctx,
struct dcerpc_pipe *p,
const char *uuid, uint_t version,
struct cli_credentials *credentials)
{
NTSTATUS status;
int chan_type = 0;
if (p->conn->flags & DCERPC_SCHANNEL_BDC) {
chan_type = SEC_CHAN_BDC;
} else if (p->conn->flags & DCERPC_SCHANNEL_WORKSTATION) {
chan_type = SEC_CHAN_WKSTA;
} else if (p->conn->flags & DCERPC_SCHANNEL_DOMAIN) {
chan_type = SEC_CHAN_DOMAIN;
}
/* Fills in NETLOGON credentials */
status = dcerpc_schannel_key(tmp_ctx,
p, credentials,
chan_type);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to setup credentials for account %s: %s\n",
cli_credentials_get_username(credentials),
nt_errstr(status)));
/*
* If we get back NT_STATUS_ACCESS_DENIED and we asked for
* DCERPC_SCHANNEL_128, then try again without
*/
if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED) &&
p->conn->flags & DCERPC_SCHANNEL_128) {
DEBUG(1, ("Retrying to setup credentials without DCERPC_SCHANNEL_128\n"));
p->conn->flags &= ~DCERPC_SCHANNEL_128;
status = dcerpc_schannel_key(tmp_ctx,
p, credentials,
chan_type);
}
if (!NT_STATUS_IS_OK(status)) {
return status;
}
}
return dcerpc_bind_auth_password(p, uuid, version,
credentials, DCERPC_AUTH_TYPE_SCHANNEL,
NULL);
}
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