added auto-determination of the DCERPC over TCP port number by asking

the servers endpoint mapper
(This used to be commit 4abf5376b00f580eb69196e55a792cc7eb4c9880)

4 files changed, 176 insertions, 6 deletions

diff --git a/source4/librpc/idl/dcerpc.idl b/source4/librpc/idl/dcerpc.idl
index 978bc5640c..c23553c444 100644
--- a/source4/librpc/idl/dcerpc.idl
+++ b/source4/librpc/idl/dcerpc.idl
@@ -31,6 +31,9 @@ interface dcerpc
 		[flag(NDR_REMAINING)] DATA_BLOB auth_info;
 	} dcerpc_bind;
 
+
+	const uint8 DCERPC_REQUEST_LENGTH = 24;
+
 	typedef struct {
 		uint32 alloc_hint;
 		uint16 context_id;
@@ -62,6 +65,8 @@ interface dcerpc
 		uint32 versions[num_versions];
 	} dcerpc_bind_nak;
 
+	const uint8 DCERPC_RESPONSE_LENGTH = 24;
+
 	typedef struct {
 		uint32 alloc_hint;
 		uint16 context_id;
@@ -140,6 +145,10 @@ interface dcerpc
 	const uint8 DCERPC_PFC_FLAG_LAST   = 0x02;
 	const uint8 DCERPC_PFC_FLAG_NOCALL = 0x20;
 
+	/* these offsets are needed by the signing code */
+	const uint8 DCERPC_FRAG_LEN_OFFSET =  8;
+	const uint8 DCERPC_AUTH_LEN_OFFSET = 10;
+
 	typedef [public] struct {
 		uint8 rpc_vers;		/* RPC version */
 		uint8 rpc_vers_minor;	/* Minor version */
diff --git a/source4/librpc/idl/epmapper.idl b/source4/librpc/idl/epmapper.idl
index 172c83149b..6fa9a7bd60 100644
--- a/source4/librpc/idl/epmapper.idl
+++ b/source4/librpc/idl/epmapper.idl
@@ -22,12 +22,20 @@ interface epmapper
 
 	/* this guid indicates NDR encoding in a protocol tower */
 	const string NDR_GUID = "8a885d04-1ceb-11c9-9fe8-08002b104860";
+	const string NDR_GUID_VERSION = 1;
 
 	typedef struct {
 		GUID uuid;
 		uint16 version;
 	} epm_prot_uuid;
 
+	typedef enum {
+		EPM_PROTOCOL_TCP   = 0x07,
+		EPM_PROTOCOL_IP    = 0x09,
+		EPM_PROTOCOL_RPC_C = 0x0b,
+		EPM_PROTOCOL_UUID  = 0x0d
+	} epm_protocols;
+
 	typedef [nodiscriminant] union {
 		[case(13)] epm_prot_uuid uuid;
 		[default]  [flag(NDR_REMAINING)] DATA_BLOB lhs_data;
@@ -58,7 +66,7 @@ interface epmapper
 	} epm_towers;
 
 	typedef struct {
-		uint32  tower_length;
+		[value(ndr_size_epm_towers(&r->towers))] uint32  tower_length;
 		[subcontext(4)] epm_towers towers;
 	} epm_twr_t;
 
diff --git a/source4/librpc/rpc/dcerpc.c b/source4/librpc/rpc/dcerpc.c
index 83fb0b592c..2fc940314d 100644
--- a/source4/librpc/rpc/dcerpc.c
+++ b/source4/librpc/rpc/dcerpc.c
@@ -43,6 +43,7 @@ struct dcerpc_pipe *dcerpc_pipe_init(void)
 	p->call_id = 1;
 	p->auth_info = NULL;
 	p->ntlmssp_state = NULL;
+	p->flags = 0;
 
 	return p;
 }
@@ -222,7 +223,8 @@ static NTSTATUS dcerpc_push_request_sign(struct dcerpc_pipe *p,
 
 	/* sign the packet */
 	status = ntlmssp_sign_packet(p->ntlmssp_state, 
-				     ndr->data+24, ndr->offset-24,
+				     ndr->data + DCERPC_REQUEST_LENGTH, 
+				     ndr->offset - DCERPC_REQUEST_LENGTH,
 				     &p->auth_info->credentials);
 	if (!NT_STATUS_IS_OK(status)) {
 		return status;
@@ -237,9 +239,11 @@ static NTSTATUS dcerpc_push_request_sign(struct dcerpc_pipe *p,
 	/* extract the whole packet as a blob */
 	*blob = ndr_push_blob(ndr);
 
-	/* fill in the fragment length and auth_length */
-	SSVAL(blob->data,  8, blob->length);
-	SSVAL(blob->data, 10, p->auth_info->credentials.length);
+	/* fill in the fragment length and auth_length, we can't fill
+	   in these earlier as we don't know the signature length (it
+	   could be variable length) */
+	SSVAL(blob->data,  DCERPC_FRAG_LEN_OFFSET, blob->length);
+	SSVAL(blob->data,  DCERPC_AUTH_LEN_OFFSET, p->auth_info->credentials.length);
 
 	data_blob_free(&p->auth_info->credentials);
 
@@ -422,7 +426,7 @@ NTSTATUS dcerpc_request(struct dcerpc_pipe *p,
 
 	/* we can write a full max_recv_frag size, minus the dcerpc
 	   request header size */
-	chunk_size = p->srv_max_recv_frag - 24;
+	chunk_size = p->srv_max_recv_frag - DCERPC_REQUEST_LENGTH;
 
 	pkt.ptype = DCERPC_PKT_REQUEST;
 	pkt.call_id = p->call_id++;
diff --git a/source4/librpc/rpc/dcerpc_util.c b/source4/librpc/rpc/dcerpc_util.c
new file mode 100644
index 0000000000..75799c1a0b
--- /dev/null
+++ b/source4/librpc/rpc/dcerpc_util.c
@@ -0,0 +1,149 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   dcerpc utility functions
+
+   Copyright (C) Andrew Tridgell 2003
+   
+   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"
+
+/*
+  this ndr_size_* stuff should really be auto-generated ....
+*/
+
+static size_t ndr_size_epm_floor(struct epm_floor *fl)
+{
+	size_t ret = 5;
+	if (fl->lhs.protocol == EPM_PROTOCOL_UUID) {
+		ret += 18;
+	} else {
+		ret += fl->lhs.info.lhs_data.length;
+	}
+	ret += fl->rhs.rhs_data.length;
+	return ret;
+}
+
+size_t ndr_size_epm_towers(struct epm_towers *towers)
+{
+	size_t ret = 2;
+	int i;
+	for (i=0;i<towers->num_floors;i++) {
+		ret += ndr_size_epm_floor(&towers->floors[i]);
+	}
+	return ret;
+}
+
+/*
+  work out what TCP port to use for a given interface on a given host
+*/
+NTSTATUS dcerpc_epm_map_tcp_port(const char *server, 
+				 const char *uuid, unsigned version,
+				 uint32 *port)
+{
+	struct dcerpc_pipe *p;
+	NTSTATUS status;
+	struct epm_Map r;
+	struct policy_handle handle;
+	GUID guid;
+	struct epm_twr_t twr, *twr_r;
+
+	status = dcerpc_pipe_open_tcp(&p, server, 135);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	/* we can use the pipes memory context here as we will have a short
+	   lived connection */
+	status = dcerpc_bind_byuuid(p, p->mem_ctx, 
+				    DCERPC_EPMAPPER_UUID,
+				    DCERPC_EPMAPPER_VERSION);
+	if (!NT_STATUS_IS_OK(status)) {
+		dcerpc_pipe_close(p);
+		return status;
+	}
+
+	ZERO_STRUCT(handle);
+	ZERO_STRUCT(guid);
+
+	twr.towers.num_floors = 5;
+	twr.towers.floors = talloc(p->mem_ctx, sizeof(twr.towers.floors[0]) * 5);
+
+	/* what I'd like for christmas ... */
+
+	/* an RPC interface ... */
+	twr.towers.floors[0].lhs.protocol = EPM_PROTOCOL_UUID;
+	GUID_from_string(uuid, &twr.towers.floors[0].lhs.info.uuid.uuid);
+	twr.towers.floors[0].lhs.info.uuid.version = version;
+	twr.towers.floors[0].rhs.rhs_data = data_blob_talloc(p->mem_ctx, NULL, 2);
+
+	/* encoded with NDR ... */
+	twr.towers.floors[1].lhs.protocol = EPM_PROTOCOL_UUID;
+	GUID_from_string(NDR_GUID, &twr.towers.floors[1].lhs.info.uuid.uuid);
+	twr.towers.floors[1].lhs.info.uuid.version = 2;
+	twr.towers.floors[1].rhs.rhs_data = data_blob_talloc(p->mem_ctx, NULL, 2);
+
+	/* on an RPC connection ... */
+	twr.towers.floors[2].lhs.protocol = EPM_PROTOCOL_RPC_C;
+	twr.towers.floors[2].lhs.info.lhs_data = data_blob(NULL, 0);
+	twr.towers.floors[2].rhs.rhs_data = data_blob_talloc(p->mem_ctx, NULL, 2);
+
+	/* on a TCP port ... */
+	twr.towers.floors[3].lhs.protocol = EPM_PROTOCOL_TCP;
+	twr.towers.floors[3].lhs.info.lhs_data = data_blob(NULL, 0);
+	twr.towers.floors[3].rhs.rhs_data = data_blob_talloc(p->mem_ctx, NULL, 2);
+
+	/* on an IP link ... */
+	twr.towers.floors[4].lhs.protocol = EPM_PROTOCOL_IP;
+	twr.towers.floors[4].lhs.info.lhs_data = data_blob(NULL, 0);
+	twr.towers.floors[4].rhs.rhs_data = data_blob_talloc(p->mem_ctx, NULL, 4);
+
+	r.in.object = &guid;
+	r.in.map_tower = &twr;
+	r.in.entry_handle = &handle;
+	r.in.max_towers = 1;
+	r.out.entry_handle = &handle;
+
+	status = dcerpc_epm_Map(p, p->mem_ctx, &r);
+	if (!NT_STATUS_IS_OK(status)) {
+		dcerpc_pipe_close(p);
+		return status;
+	}
+	if (r.out.status != 0 || r.out.num_towers != 1) {
+		dcerpc_pipe_close(p);
+		return NT_STATUS_PORT_UNREACHABLE;
+	}
+
+	twr_r = r.out.towers[0].twr;
+	if (!twr_r) {
+		dcerpc_pipe_close(p);
+		return NT_STATUS_PORT_UNREACHABLE;
+	}
+
+	if (twr_r->towers.num_floors != 5 ||
+	    twr_r->towers.floors[3].lhs.protocol != EPM_PROTOCOL_TCP ||
+	    twr_r->towers.floors[3].rhs.rhs_data.length != 2) {
+		dcerpc_pipe_close(p);
+		return NT_STATUS_PORT_UNREACHABLE;
+	}
+
+	*port = RSVAL(twr_r->towers.floors[3].rhs.rhs_data.data, 0);
+
+	dcerpc_pipe_close(p);
+
+	return NT_STATUS_OK;
+}