1 files changed, 277 insertions, 0 deletions

diff --git a/source4/libcli/finddcs.c b/source4/libcli/finddcs.c
new file mode 100644
index 0000000000..56f931ce19
--- /dev/null
+++ b/source4/libcli/finddcs.c
@@ -0,0 +1,277 @@
+/* 
+   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 "lib/messaging/irpc.h"
+#include "librpc/gen_ndr/ndr_irpc.h"
+#include "librpc/gen_ndr/samr.h"
+#include "libcli/composite/composite.h"
+#include "libcli/libcli.h"
+#include "libcli/resolve/resolve.h"
+#include "libcli/finddcs.h"
+#include "param/param.h"
+
+struct finddcs_state {
+	struct composite_context *ctx;
+	struct messaging_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;
+
+	struct smb_iconv_convenience *iconv_convenience;
+
+	int num_dcs;
+	struct nbt_dc_name *dcs;
+	uint16_t nbt_port;
+};
+
+static void finddcs_name_resolved(struct composite_context *ctx);
+static void finddcs_getdc_replied(struct irpc_request *ireq);
+static void fallback_node_status(struct finddcs_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 composite_context *finddcs_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 smb_iconv_convenience *iconv_convenience,
+				       struct resolve_context *resolve_ctx,
+				       struct event_context *event_ctx,
+				       struct messaging_context *msg_ctx)
+{
+	struct composite_context *c, *creq;
+	struct finddcs_state *state;
+	struct nbt_name name;
+
+	c = composite_create(mem_ctx, event_ctx);
+	if (c == NULL) return NULL;
+
+	state = talloc(c, struct finddcs_state);
+	if (composite_nomem(state, c)) return c;
+	c->private_data = state;
+
+	state->ctx = c;
+
+	state->nbt_port = nbt_port;
+	state->my_netbios_name = talloc_strdup(state, my_netbios_name);
+	state->domain_name = talloc_strdup(state, domain_name);
+	state->iconv_convenience = iconv_convenience;
+	if (composite_nomem(state->domain_name, c)) return c;
+
+	if (domain_sid) {
+		state->domain_sid = talloc_reference(state, domain_sid);
+		if (composite_nomem(state->domain_sid, c)) return c;
+	} 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, &name, event_ctx);
+	composite_continue(c, creq, finddcs_name_resolved, state);
+	return c;
+}
+
+/* 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_name_resolved(struct composite_context *ctx)
+{
+	struct finddcs_state *state =
+		talloc_get_type(ctx->async.private_data, struct finddcs_state);
+	struct irpc_request *ireq;
+	struct server_id *nbt_servers;
+	const char *address;
+
+	state->ctx->status = resolve_name_recv(ctx, state, &address);
+	if (!composite_is_ok(state->ctx)) 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 (composite_nomem(state->dcs, state->ctx)) 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;
+	}
+
+	nbt_servers = irpc_servers_byname(state->msg_ctx, state, "nbt_server");
+	if ((nbt_servers == NULL) || (nbt_servers[0].id == 0)) {
+		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 (composite_nomem(state->r.in.my_accountname, state->ctx)) return;
+	state->r.in.account_control = ACB_WSTRUST;
+	state->r.in.domain_sid = state->domain_sid;
+
+	ireq = irpc_call_send(state->msg_ctx, nbt_servers[0],
+			      &ndr_table_irpc, NDR_NBTD_GETDCNAME,
+			      &state->r, state);
+	if (!ireq) {
+		fallback_node_status(state);
+		return;
+	}
+
+	composite_continue_irpc(state->ctx, ireq, finddcs_getdc_replied, state);
+}
+
+/* Called when the GetDC request returns */
+static void finddcs_getdc_replied(struct irpc_request *ireq)
+{
+	struct finddcs_state *state =
+		talloc_get_type(ireq->async.private, struct finddcs_state);
+
+	state->ctx->status = irpc_call_recv(ireq);
+	if (!composite_is_ok(state->ctx)) return;
+
+	state->dcs[0].name = talloc_steal(state->dcs, state->r.out.dcname);
+	composite_done(state->ctx);
+}
+
+/* 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_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->ctx->event_ctx, 
+				       state->iconv_convenience);
+	if (composite_nomem(nbtsock, state->ctx)) return;
+	
+	name_req = nbt_name_status_send(nbtsock, &state->node_status);
+	if (composite_nomem(name_req, state->ctx)) return;
+
+	composite_continue_nbt(state->ctx, 
+			       name_req, 
+			       fallback_node_status_replied,
+			       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_state *state = talloc_get_type(name_req->async.private, struct finddcs_state);
+	state->ctx->status = nbt_name_status_recv(name_req, state, &state->node_status);
+	if (!composite_is_ok(state->ctx)) 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;
+			composite_done(state->ctx);
+			return;
+		}
+	}
+	composite_error(state->ctx, NT_STATUS_NO_LOGON_SERVERS);
+}
+
+NTSTATUS finddcs_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
+		      int *num_dcs, struct nbt_dc_name **dcs)
+{
+	NTSTATUS status = composite_wait(c);
+	if (NT_STATUS_IS_OK(status)) {
+		struct finddcs_state *state =
+			talloc_get_type(c->private_data, struct finddcs_state);
+		*num_dcs = state->num_dcs;
+		*dcs = talloc_steal(mem_ctx, state->dcs);
+	}
+	talloc_free(c);
+	return status;
+}
+
+NTSTATUS finddcs(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 smb_iconv_convenience *iconv_convenience,
+		 struct resolve_context *resolve_ctx,
+		 struct event_context *event_ctx,
+		 struct messaging_context *msg_ctx,
+		 int *num_dcs, struct nbt_dc_name **dcs)
+{
+	struct composite_context *c = finddcs_send(mem_ctx,
+						   my_netbios_name,
+						   nbt_port,
+						   domain_name, name_type,
+						   domain_sid, 
+						   iconv_convenience,
+						   resolve_ctx,
+						   event_ctx, msg_ctx);
+	return finddcs_recv(c, mem_ctx, num_dcs, dcs);
+}