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/*
Unix SMB/CIFS implementation.
server side dcerpc common code
Copyright (C) Andrew Tridgell 2003-2010
Copyright (C) Stefan (metze) Metzmacher 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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "librpc/rpc/dcesrv_core.h"
#include "librpc/rpc/dcesrv_core_proto.h"
#include "librpc/rpc/dcerpc_util.h"
#include "auth/gensec/gensec.h"
#include "lib/util/dlinklist.h"
#include "param/param.h"
/*
move a call from an existing linked list to the specified list. This
prevents bugs where we forget to remove the call from a previous
list when moving it.
*/
static void dcesrv_call_set_list(struct dcesrv_call_state *call,
enum dcesrv_call_list list)
{
switch (call->list) {
case DCESRV_LIST_NONE:
break;
case DCESRV_LIST_CALL_LIST:
DLIST_REMOVE(call->conn->call_list, call);
break;
case DCESRV_LIST_FRAGMENTED_CALL_LIST:
DLIST_REMOVE(call->conn->incoming_fragmented_call_list, call);
break;
case DCESRV_LIST_PENDING_CALL_LIST:
DLIST_REMOVE(call->conn->pending_call_list, call);
break;
}
call->list = list;
switch (list) {
case DCESRV_LIST_NONE:
break;
case DCESRV_LIST_CALL_LIST:
DLIST_ADD_END(call->conn->call_list, call);
break;
case DCESRV_LIST_FRAGMENTED_CALL_LIST:
DLIST_ADD_END(call->conn->incoming_fragmented_call_list, call);
break;
case DCESRV_LIST_PENDING_CALL_LIST:
DLIST_ADD_END(call->conn->pending_call_list, call);
break;
}
}
void dcesrv_init_hdr(struct ncacn_packet *pkt, bool bigendian)
{
pkt->rpc_vers = 5;
pkt->rpc_vers_minor = 0;
if (bigendian) {
pkt->drep[0] = 0;
} else {
pkt->drep[0] = DCERPC_DREP_LE;
}
pkt->drep[1] = 0;
pkt->drep[2] = 0;
pkt->drep[3] = 0;
}
/*
return a dcerpc fault
*/
NTSTATUS dcesrv_fault_with_flags(struct dcesrv_call_state *call,
uint32_t fault_code,
uint8_t extra_flags)
{
struct ncacn_packet pkt;
struct data_blob_list_item *rep;
NTSTATUS status;
if (call->conn->terminate != NULL) {
/*
* If we're already disconnecting
* we should just drop a possible
* response
*/
talloc_free(call);
return NT_STATUS_OK;
}
/* setup a fault */
dcesrv_init_hdr(&pkt, lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
pkt.auth_length = 0;
pkt.call_id = call->pkt.call_id;
pkt.ptype = DCERPC_PKT_FAULT;
pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST | extra_flags;
pkt.u.fault.alloc_hint = 24;
if (call->context != NULL) {
pkt.u.fault.context_id = call->context->context_id;
} else {
pkt.u.fault.context_id = 0;
}
pkt.u.fault.cancel_count = 0;
pkt.u.fault.flags = 0;
pkt.u.fault.status = fault_code;
pkt.u.fault.reserved = 0;
pkt.u.fault.error_and_verifier = data_blob_null;
rep = talloc_zero(call, struct data_blob_list_item);
if (!rep) {
return NT_STATUS_NO_MEMORY;
}
status = dcerpc_ncacn_push_auth(&rep->blob, call, &pkt, NULL);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
dcerpc_set_frag_length(&rep->blob, rep->blob.length);
DLIST_ADD_END(call->replies, rep);
dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);
if (call->conn->call_list && call->conn->call_list->replies) {
if (call->conn->transport.report_output_data) {
call->conn->transport.report_output_data(call->conn);
}
}
return NT_STATUS_OK;
}
NTSTATUS dcesrv_fault(struct dcesrv_call_state *call, uint32_t fault_code)
{
return dcesrv_fault_with_flags(call, fault_code, 0);
}
_PUBLIC_ NTSTATUS dcesrv_reply(struct dcesrv_call_state *call)
{
struct ndr_push *push;
NTSTATUS status;
DATA_BLOB stub;
uint32_t total_length, chunk_size;
struct dcesrv_connection_context *context = call->context;
struct dcesrv_auth *auth = call->auth_state;
size_t sig_size = 0;
/*
* call the reply function,
* it's mostly for debug messages
* and dcesrv_fault() also checks for
* (call->conn->terminate != NULL) internally.
*/
status = context->iface->reply(call, call, call->r);
if (!NT_STATUS_IS_OK(status)) {
return dcesrv_fault(call, call->fault_code);
}
if (call->conn->terminate != NULL) {
/*
* If we're already disconnecting
* we should just drop a possible
* response
*/
talloc_free(call);
return NT_STATUS_OK;
}
/* form the reply NDR */
push = ndr_push_init_ctx(call);
NT_STATUS_HAVE_NO_MEMORY(push);
/* carry over the pointer count to the reply in case we are
using full pointer. See NDR specification for full
pointers */
push->ptr_count = call->ndr_pull->ptr_count;
if (lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx)) {
push->flags |= LIBNDR_FLAG_BIGENDIAN;
}
if (context->ndr64) {
push->flags |= LIBNDR_FLAG_NDR64;
}
status = context->iface->ndr_push(call, call, push, call->r);
if (!NT_STATUS_IS_OK(status)) {
return dcesrv_fault(call, call->fault_code);
}
stub = ndr_push_blob(push);
dcesrv_save_ndr_fuzz_seed(stub,
call,
NDR_OUT);
total_length = stub.length;
/* we can write a full max_recv_frag size, minus the dcerpc
request header size */
chunk_size = call->conn->max_xmit_frag;
chunk_size -= DCERPC_REQUEST_LENGTH;
if (auth->auth_finished && auth->gensec_security != NULL) {
size_t max_payload = chunk_size;
max_payload -= DCERPC_AUTH_TRAILER_LENGTH;
max_payload -= (max_payload % DCERPC_AUTH_PAD_ALIGNMENT);
sig_size = gensec_sig_size(auth->gensec_security,
max_payload);
if (sig_size) {
chunk_size -= DCERPC_AUTH_TRAILER_LENGTH;
chunk_size -= sig_size;
}
}
chunk_size -= (chunk_size % DCERPC_AUTH_PAD_ALIGNMENT);
do {
uint32_t length;
struct data_blob_list_item *rep;
struct ncacn_packet pkt;
bool ok;
rep = talloc_zero(call, struct data_blob_list_item);
NT_STATUS_HAVE_NO_MEMORY(rep);
length = MIN(chunk_size, stub.length);
/* form the dcerpc response packet */
dcesrv_init_hdr(&pkt,
lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
pkt.auth_length = 0;
pkt.call_id = call->pkt.call_id;
pkt.ptype = DCERPC_PKT_RESPONSE;
pkt.pfc_flags = 0;
if (stub.length == total_length) {
pkt.pfc_flags |= DCERPC_PFC_FLAG_FIRST;
}
if (length == stub.length) {
pkt.pfc_flags |= DCERPC_PFC_FLAG_LAST;
}
pkt.u.response.alloc_hint = stub.length;
/*
* bug for bug, feature for feature...
*
* Windows truncates the context_id with & 0xFF,
* so we do.
*/
pkt.u.response.context_id = context->context_id & 0xFF;
pkt.u.response.cancel_count = 0;
pkt.u.response.stub_and_verifier.data = stub.data;
pkt.u.response.stub_and_verifier.length = length;
ok = dcesrv_auth_pkt_push(call, &rep->blob, sig_size,
DCERPC_RESPONSE_LENGTH,
&pkt.u.response.stub_and_verifier,
&pkt);
if (!ok) {
return dcesrv_fault(call, DCERPC_FAULT_OTHER);
}
dcerpc_set_frag_length(&rep->blob, rep->blob.length);
DLIST_ADD_END(call->replies, rep);
stub.data += length;
stub.length -= length;
} while (stub.length != 0);
/* move the call from the pending to the finished calls list */
dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);
if (call->conn->call_list && call->conn->call_list->replies) {
if (call->conn->transport.report_output_data) {
call->conn->transport.report_output_data(call->conn);
}
}
return NT_STATUS_OK;
}
_PUBLIC_ void _dcesrv_async_reply(struct dcesrv_call_state *call,
const char *func,
const char *location)
{
struct dcesrv_connection *conn = call->conn;
NTSTATUS status;
status = dcesrv_reply(call);
if (!NT_STATUS_IS_OK(status)) {
D_ERR("%s: %s: dcesrv_async_reply() failed - %s\n",
func, location, nt_errstr(status));
dcesrv_terminate_connection(conn, nt_errstr(status));
}
}
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