s3:winbind: Add NDR-based parent-child communication to winbind

1 files changed, 273 insertions, 0 deletions

diff --git a/source3/winbindd/winbindd_dual_ndr.c b/source3/winbindd/winbindd_dual_ndr.c
new file mode 100644
index 0000000000..f72d6615a0
--- /dev/null
+++ b/source3/winbindd/winbindd_dual_ndr.c
@@ -0,0 +1,273 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   Provide parent->child communication based on NDR marshalling
+
+   Copyright (C) Volker Lendecke 2009
+
+   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/>.
+*/
+
+/*
+ * This file implements an RPC between winbind parent and child processes,
+ * leveraging the autogenerated marshalling routines for MSRPC. This is not
+ * MSRPC, as it does not go through the whole DCERPC fragmentation, we just
+ * leverage much the same infrastructure we already have for it.
+ */
+
+#include "includes.h"
+#include "winbindd/winbindd.h"
+#include "winbindd/winbindd_proto.h"
+#include "librpc/gen_ndr/srv_wbint.h"
+
+struct wb_ndr_transport_priv {
+	struct winbindd_child *child;
+};
+
+struct wb_ndr_dispatch_state {
+	const struct ndr_interface_call *call;
+	void *r;
+	struct ndr_push *push;
+	struct winbindd_request request;
+	struct winbindd_response *response;
+};
+
+static void wb_ndr_dispatch_done(struct tevent_req *subreq);
+
+static struct tevent_req *wb_ndr_dispatch_send(TALLOC_CTX *mem_ctx,
+					       struct tevent_context *ev,
+					       struct rpc_pipe_client *cli,
+					       const struct ndr_interface_table *table,
+					       uint32_t opnum,
+					       void *r)
+{
+	struct tevent_req *req, *subreq;
+	struct wb_ndr_dispatch_state *state;
+	struct wb_ndr_transport_priv *transport = talloc_get_type_abort(
+		cli->transport->priv, struct wb_ndr_transport_priv);
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+
+	req = tevent_req_create(mem_ctx, &state,
+				struct wb_ndr_dispatch_state);
+	if (req == NULL) {
+		return NULL;
+	}
+
+	state->r = r;
+	state->call = &table->calls[opnum];
+
+	state->push = ndr_push_init_ctx(state, NULL);
+	if (tevent_req_nomem(state->push, req)) {
+		return tevent_req_post(req, ev);
+	}
+
+	ndr_err = state->call->ndr_push(state->push, NDR_IN, r);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		tevent_req_nterror(req, ndr_map_error2ntstatus(ndr_err));
+		TALLOC_FREE(state->push);
+		return tevent_req_post(req, ev);
+	}
+
+	blob = ndr_push_blob(state->push);
+
+	state->request.cmd = WINBINDD_DUAL_NDRCMD;
+	state->request.data.ndrcmd = opnum;
+	state->request.extra_data.data = (char *)blob.data;
+	state->request.extra_len = blob.length;
+
+	subreq = wb_child_request_send(state, ev, transport->child,
+				       &state->request);
+	if (tevent_req_nomem(subreq, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_req_set_callback(subreq, wb_ndr_dispatch_done, req);
+	return req;
+}
+
+static void wb_ndr_dispatch_done(struct tevent_req *subreq)
+{
+	struct tevent_req *req = tevent_req_callback_data(
+		subreq, struct tevent_req);
+	struct wb_ndr_dispatch_state *state = tevent_req_data(
+		req, struct wb_ndr_dispatch_state);
+	int ret, err;
+
+	ret = wb_child_request_recv(subreq, state, &state->response, &err);
+	TALLOC_FREE(subreq);
+	if (ret == -1) {
+		tevent_req_nterror(req, map_nt_error_from_unix(err));
+		return;
+	}
+	tevent_req_done(req);
+}
+
+static NTSTATUS wb_ndr_dispatch_recv(struct tevent_req *req,
+				     TALLOC_CTX *mem_ctx)
+{
+	struct wb_ndr_dispatch_state *state = tevent_req_data(
+		req, struct wb_ndr_dispatch_state);
+	NTSTATUS status;
+	struct ndr_pull *pull;
+	enum ndr_err_code ndr_err;
+	DATA_BLOB blob;
+
+	if (tevent_req_is_nterror(req, &status)) {
+		return status;
+	}
+
+	blob.data = (uint8_t *)state->response->extra_data.data;
+	blob.length = state->response->length
+		- sizeof(struct winbindd_response);
+
+	pull = ndr_pull_init_blob(&blob, mem_ctx, NULL);
+	if (pull == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	/* have the ndr parser alloc memory for us */
+	pull->flags |= LIBNDR_FLAG_REF_ALLOC;
+	ndr_err = state->call->ndr_pull(pull, NDR_OUT, state->r);
+	TALLOC_FREE(pull);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	return NT_STATUS_OK;
+}
+
+static NTSTATUS wb_ndr_dispatch(struct rpc_pipe_client *cli,
+				TALLOC_CTX *mem_ctx,
+				const struct ndr_interface_table *table,
+				uint32_t opnum, void *r)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct event_context *ev;
+	struct tevent_req *req;
+	NTSTATUS status = NT_STATUS_OK;
+
+	ev = event_context_init(frame);
+	if (ev == NULL) {
+		status = NT_STATUS_NO_MEMORY;
+		goto fail;
+	}
+
+	req = wb_ndr_dispatch_send(frame, ev, cli, table, opnum, r);
+	if (req == NULL) {
+		status = NT_STATUS_NO_MEMORY;
+		goto fail;
+	}
+
+	if (!tevent_req_poll(req, ev)) {
+		status = map_nt_error_from_unix(errno);
+		goto fail;
+	}
+
+	status = wb_ndr_dispatch_recv(req, mem_ctx);
+ fail:
+	TALLOC_FREE(frame);
+	return status;
+}
+
+struct rpc_pipe_client *wbint_rpccli_create(TALLOC_CTX *mem_ctx,
+					    struct winbindd_child *child)
+{
+	struct rpc_pipe_client *result;
+	struct wb_ndr_transport_priv *transp;
+
+	result = talloc(mem_ctx, struct rpc_pipe_client);
+	if (result == NULL) {
+		return NULL;
+	}
+	result->abstract_syntax = ndr_table_wbint.syntax_id;
+	result->transfer_syntax = ndr_transfer_syntax;
+	result->dispatch = wb_ndr_dispatch;
+	result->dispatch_send = wb_ndr_dispatch_send;
+	result->dispatch_recv = wb_ndr_dispatch_recv;
+	result->max_xmit_frag = RPC_MAX_PDU_FRAG_LEN;
+	result->max_recv_frag = RPC_MAX_PDU_FRAG_LEN;
+	result->desthost = NULL;
+	result->srv_name_slash = NULL;
+
+	/*
+	 * Initialize a fake transport. Due to our own wb_ndr_dispatch
+	 * function we don't use all the fragmentation engine in
+	 * cli_pipe, which would use all the _read and _write
+	 * functions in rpc_cli_transport. But we need a place to
+	 * store the child struct in, and we're re-using
+	 * result->transport->priv for that.
+	 */
+
+	result->transport = talloc_zero(result, struct rpc_cli_transport);
+	if (result->transport == NULL) {
+		TALLOC_FREE(result);
+		return NULL;
+	}
+	transp = talloc(result->transport, struct wb_ndr_transport_priv);
+	if (transp == NULL) {
+		TALLOC_FREE(result);
+		return NULL;
+	}
+	transp->child = child;
+	result->transport->priv = transp;
+	return result;
+}
+
+enum winbindd_result winbindd_dual_ndrcmd(struct winbindd_domain *domain,
+					  struct winbindd_cli_state *state)
+{
+	pipes_struct p;
+	struct api_struct *fns;
+	int num_fns;
+	bool ret;
+
+	wbint_get_pipe_fns(&fns, &num_fns);
+
+	if (state->request->data.ndrcmd >= num_fns) {
+		return WINBINDD_ERROR;
+	}
+
+	ZERO_STRUCT(p);
+	p.mem_ctx = talloc_stackframe();
+	p.in_data.data.buffer_size = state->request->extra_len;
+	p.in_data.data.data_p = state->request->extra_data.data;
+	prs_init(&p.out_data.rdata, 0, state->mem_ctx, false);
+
+	ret = fns[state->request->data.ndrcmd].fn(&p);
+	TALLOC_FREE(p.mem_ctx);
+	if (!ret) {
+		return WINBINDD_ERROR;
+	}
+
+	state->response->extra_data.data =
+		talloc_memdup(state->mem_ctx, p.out_data.rdata.data_p,
+			      p.out_data.rdata.data_offset);
+	state->response->length += p.out_data.rdata.data_offset;
+	prs_mem_free(&p.out_data.rdata);
+	if (state->response->extra_data.data == NULL) {
+		return WINBINDD_ERROR;
+	}
+	return WINBINDD_OK;
+}
+
+/*
+ * Just a dummy to make srv_wbint.c happy
+ */
+NTSTATUS rpc_srv_register(int version, const char *clnt, const char *srv,
+			  const struct ndr_interface_table *iface,
+			  const struct api_struct *cmds, int size)
+{
+	return NT_STATUS_OK;
+}