Revert "s4-libcli: Remove unused finddcs_nbt"

This reverts commit 06c90cb6f55701effa4cbafaf189a4de8471949b.

There is genuine interest in using this currently unused code, so put
it back into the tree to avoid folks having to rewrite it.

It should be carefully hooked back into libnet at some point, and
possibly told how to talk to the s3 nmbd socket if nbt_server isn't
running.

The wscript patches are skipped, due to the way the extra
dep interacted with the build system.  When used, this will be resolved.

Andrew Bartlett

1 files changed, 311 insertions, 0 deletions

diff --git a/source4/libcli/finddcs_nbt.c b/source4/libcli/finddcs_nbt.c
new file mode 100644
index 0000000000..6a5d1fd856
--- /dev/null
+++ b/source4/libcli/finddcs_nbt.c
@@ -0,0 +1,311 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   a composite API for finding a DC and its name
+
+   Copyright (C) Volker Lendecke 2005
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006
+
+   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 "include/includes.h"
+#include <tevent.h>
+#include "lib/messaging/irpc.h"
+#include "librpc/gen_ndr/ndr_irpc_c.h"
+#include "libcli/composite/composite.h"
+#include "libcli/libcli.h"
+#include "libcli/resolve/resolve.h"
+#include "lib/util/tevent_ntstatus.h"
+#include "libcli/finddc.h"
+
+struct finddcs_nbt_state {
+	struct tevent_context *ev;
+	struct tevent_req *req;
+	struct imessaging_context *msg_ctx;
+
+	const char *my_netbios_name;
+	const char *domain_name;
+	struct dom_sid *domain_sid;
+
+	struct nbtd_getdcname r;
+	struct nbt_name_status node_status;
+
+	int num_dcs;
+	struct nbt_dc_name *dcs;
+	uint16_t nbt_port;
+};
+
+static void finddcs_nbt_name_resolved(struct composite_context *ctx);
+static void finddcs_nbt_getdc_replied(struct tevent_req *subreq);
+static void fallback_node_status(struct finddcs_nbt_state *state);
+static void fallback_node_status_replied(struct nbt_name_request *name_req);
+
+/*
+ * Setup and send off the a normal name resolution for the target name.
+ *
+ * The domain_sid parameter is optional, and is used in the subsequent getdc request.
+ *
+ * This will try a GetDC request, but this may not work.  It will try
+ * a node status as a fallback, then return no name (but still include
+ * the IP)
+ */
+
+struct tevent_req *finddcs_nbt_send(TALLOC_CTX *mem_ctx,
+				const char *my_netbios_name,
+				uint16_t nbt_port,
+				const char *domain_name,
+				int name_type,
+				struct dom_sid *domain_sid,
+				struct resolve_context *resolve_ctx,
+				struct tevent_context *event_ctx,
+				struct imessaging_context *msg_ctx)
+{
+	struct finddcs_nbt_state *state;
+	struct nbt_name name;
+	struct tevent_req *req;
+	struct composite_context *creq;
+
+	req = tevent_req_create(mem_ctx, &state, struct finddcs_nbt_state);
+	if (req == NULL) {
+		return NULL;
+	}
+
+	state->req = req;
+	state->ev = event_ctx;
+	state->nbt_port = nbt_port;
+	state->my_netbios_name = talloc_strdup(state, my_netbios_name);
+	if (tevent_req_nomem(state->my_netbios_name, req)) {
+		return tevent_req_post(req, event_ctx);
+	}
+	state->domain_name = talloc_strdup(state, domain_name);
+	if (tevent_req_nomem(state->domain_name, req)) {
+		return tevent_req_post(req, event_ctx);
+	}
+
+	if (domain_sid) {
+		state->domain_sid = talloc_reference(state, domain_sid);
+		if (tevent_req_nomem(state->domain_sid, req)) {
+			return tevent_req_post(req, event_ctx);
+		}
+	} else {
+		state->domain_sid = NULL;
+	}
+
+	state->msg_ctx = msg_ctx;
+
+	make_nbt_name(&name, state->domain_name, name_type);
+	creq = resolve_name_send(resolve_ctx, state, &name, event_ctx);
+	if (tevent_req_nomem(creq, req)) {
+		return tevent_req_post(req, event_ctx);
+	}
+	creq->async.fn = finddcs_nbt_name_resolved;
+	creq->async.private_data = state;
+
+	return req;
+}
+
+/* Having got an name query answer, fire off a GetDC request, so we
+ * can find the target's all-important name.  (Kerberos and some
+ * netlogon operations are quite picky about names)
+ *
+ * The name is a courtesy, if we don't find it, don't completely fail.
+ *
+ * However, if the nbt server is down, fall back to a node status
+ * request
+ */
+static void finddcs_nbt_name_resolved(struct composite_context *ctx)
+{
+	struct finddcs_nbt_state *state =
+		talloc_get_type(ctx->async.private_data, struct finddcs_nbt_state);
+	struct tevent_req *subreq;
+	struct dcerpc_binding_handle *irpc_handle;
+	const char *address;
+	NTSTATUS status;
+
+	status = resolve_name_recv(ctx, state, &address);
+	if (tevent_req_nterror(state->req, status)) {
+		return;
+	}
+
+	/* TODO: This should try and find all the DCs, and give the
+	 * caller them in the order they responded */
+
+	state->num_dcs = 1;
+	state->dcs = talloc_array(state, struct nbt_dc_name, state->num_dcs);
+	if (tevent_req_nomem(state->dcs, state->req)) {
+		return;
+	}
+
+	state->dcs[0].address = talloc_steal(state->dcs, address);
+
+	/* Try and find the nbt server.  Fallback to a node status
+	 * request if we can't make this happen The nbt server just
+	 * might not be running, or we may not have a messaging
+	 * context (not root etc) */
+	if (!state->msg_ctx) {
+		fallback_node_status(state);
+		return;
+	}
+
+	irpc_handle = irpc_binding_handle_by_name(state, state->msg_ctx,
+						  "nbt_server", &ndr_table_irpc);
+	if (irpc_handle == NULL) {
+		fallback_node_status(state);
+		return;
+	}
+
+	state->r.in.domainname = state->domain_name;
+	state->r.in.ip_address = state->dcs[0].address;
+	state->r.in.my_computername = state->my_netbios_name;
+	state->r.in.my_accountname = talloc_asprintf(state, "%s$", state->my_netbios_name);
+	if (tevent_req_nomem(state->r.in.my_accountname, state->req)) {
+		return;
+	}
+	state->r.in.account_control = ACB_WSTRUST;
+	state->r.in.domain_sid = state->domain_sid;
+	if (state->r.in.domain_sid == NULL) {
+		state->r.in.domain_sid = talloc_zero(state, struct dom_sid);
+	}
+
+	subreq = dcerpc_nbtd_getdcname_r_send(state, state->ev,
+					      irpc_handle, &state->r);
+	if (tevent_req_nomem(subreq, state->req)) {
+		return;
+	}
+	tevent_req_set_callback(subreq, finddcs_nbt_getdc_replied, state);
+}
+
+/* Called when the GetDC request returns */
+static void finddcs_nbt_getdc_replied(struct tevent_req *subreq)
+{
+	struct finddcs_nbt_state *state =
+		tevent_req_callback_data(subreq,
+		struct finddcs_nbt_state);
+	NTSTATUS status;
+
+	status = dcerpc_nbtd_getdcname_r_recv(subreq, state);
+	TALLOC_FREE(subreq);
+	if (!NT_STATUS_IS_OK(status)) {
+		fallback_node_status(state);
+		return;
+	}
+
+	state->dcs[0].name = talloc_steal(state->dcs, state->r.out.dcname);
+	tevent_req_done(state->req);
+}
+
+/* The GetDC request might not be available (such as occours when the
+ * NBT server is down).  Fallback to a node status.  It is the best
+ * hope we have... */
+static void fallback_node_status(struct finddcs_nbt_state *state)
+{
+	struct nbt_name_socket *nbtsock;
+	struct nbt_name_request *name_req;
+
+	state->node_status.in.name.name = "*";
+	state->node_status.in.name.type = NBT_NAME_CLIENT;
+	state->node_status.in.name.scope = NULL;
+	state->node_status.in.dest_addr = state->dcs[0].address;
+	state->node_status.in.dest_port = state->nbt_port;
+	state->node_status.in.timeout = 1;
+	state->node_status.in.retries = 2;
+
+	nbtsock = nbt_name_socket_init(state, state->ev);
+	if (tevent_req_nomem(nbtsock, state->req)) {
+		return;
+	}
+
+	name_req = nbt_name_status_send(nbtsock, &state->node_status);
+	if (tevent_req_nomem(name_req, state->req)) {
+		return;
+	}
+
+	name_req->async.fn = fallback_node_status_replied;
+	name_req->async.private_data = state;
+}
+
+/* We have a node status reply (or perhaps a timeout) */
+static void fallback_node_status_replied(struct nbt_name_request *name_req)
+{
+	int i;
+	struct finddcs_nbt_state *state = talloc_get_type(name_req->async.private_data, struct finddcs_nbt_state);
+	NTSTATUS status;
+
+	status = nbt_name_status_recv(name_req, state, &state->node_status);
+	if (tevent_req_nterror(state->req, status)) {
+		return;
+	}
+
+	for (i=0; i < state->node_status.out.status.num_names; i++) {
+		int j;
+		if (state->node_status.out.status.names[i].type == NBT_NAME_SERVER) {
+			char *name = talloc_strndup(state->dcs, state->node_status.out.status.names[0].name, 15);
+			/* Strip space padding */
+			if (name) {
+				j = MIN(strlen(name), 15);
+				for (; j > 0 && name[j - 1] == ' '; j--) {
+					name[j - 1] = '\0';
+				}
+			}
+			state->dcs[0].name = name;
+			tevent_req_done(state->req);
+			return;
+		}
+	}
+	tevent_req_nterror(state->req, NT_STATUS_NO_LOGON_SERVERS);
+}
+
+NTSTATUS finddcs_nbt_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+		      int *num_dcs, struct nbt_dc_name **dcs)
+{
+	struct finddcs_nbt_state *state = tevent_req_data(req, struct finddcs_nbt_state);
+	bool ok;
+	NTSTATUS status;
+
+	ok = tevent_req_poll(req, state->ev);
+	if (!ok) {
+		talloc_free(req);
+		return NT_STATUS_INTERNAL_ERROR;
+	}
+	status = tevent_req_simple_recv_ntstatus(req);
+	if (NT_STATUS_IS_OK(status)) {
+		*num_dcs = state->num_dcs;
+		*dcs = talloc_steal(mem_ctx, state->dcs);
+	}
+	return status;
+}
+
+NTSTATUS finddcs_nbt(TALLOC_CTX *mem_ctx,
+		 const char *my_netbios_name,
+		 uint16_t nbt_port,
+		 const char *domain_name, int name_type,
+		 struct dom_sid *domain_sid,
+		 struct resolve_context *resolve_ctx,
+		 struct tevent_context *event_ctx,
+		 struct imessaging_context *msg_ctx,
+		 int *num_dcs, struct nbt_dc_name **dcs)
+{
+	NTSTATUS status;
+	struct tevent_req *req = finddcs_nbt_send(mem_ctx,
+					      my_netbios_name,
+					      nbt_port,
+					      domain_name, name_type,
+					      domain_sid,
+					      resolve_ctx,
+					      event_ctx, msg_ctx);
+	status = finddcs_nbt_recv(req, mem_ctx, num_dcs, dcs);
+	talloc_free(req);
+	return status;
+}