a fairly major upgrade to the dcerpc system

 * added a NDR validator. The way it works is that when the
   DCERPC_DEBUG_VALIDATE_* flags are set the dcerpc system will
   perform NDR buffer validation. On sending a request the packet is
   first marshalled, then unmarahslled, then marshalled again, and it is
   confirmed that the two marshalling results are idential. This
   ensures that our pull and push routines are absolutely in sync, so
   that we can be very confident that if a routine works in the client
   then the corresponding routine must work on the server side. A
   similar validation is performed on all replies.

 * a result of this change is that pidl is fussier about the [ref]
   tag. You can only use it on pointers (which is the only place it
   makes sense)

 * fixed a basic alignment bug in the push side of the NDR code

 * added server side pull/push support. Our dcerpc system is now fully
   ready to be used on the server side.

 * fixed the relative offset pointer list. It must be traversed in
   reverse order on push

 * added automatic value setting for the size parameter in outgoing
   SdBuf structures.

 * expanded the ndr debugging code to always give a message on any
   failure

 * fixed the subcontext push code

 * fixed some memory leaks in smbtorture RPC tests
(This used to be commit 8ecf720206a2eef3f8ea7cbdb1f460664a5dba9a)

2 files changed, 160 insertions, 6 deletions

diff --git a/source4/librpc/rpc/dcerpc.c b/source4/librpc/rpc/dcerpc.c
index 7fa24bb171..cb03ff8970 100644
--- a/source4/librpc/rpc/dcerpc.c
+++ b/source4/librpc/rpc/dcerpc.c
@@ -731,6 +731,139 @@ NTSTATUS dcerpc_request(struct dcerpc_pipe *p,
 
 
 /*
+  this is a paranoid NDR validator. For every packet we push onto the wire
+  we pull it back again, then push it again. Then we compare the raw NDR data
+  for that to the NDR we initially generated. If they don't match then we know
+  we must have a bug in either the pull or push side of our code
+*/
+static NTSTATUS dcerpc_ndr_validate_in(TALLOC_CTX *mem_ctx,
+				       DATA_BLOB blob,
+				       size_t struct_size,
+				       NTSTATUS (*ndr_push)(struct ndr_push *, int, void *),
+				       NTSTATUS (*ndr_pull)(struct ndr_pull *, int, void *))
+{
+	void *st;
+	struct ndr_pull *pull;
+	struct ndr_push *push;
+	NTSTATUS status;
+	DATA_BLOB blob2;
+
+	st = talloc(mem_ctx, struct_size);
+	if (!st) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	pull = ndr_pull_init_blob(&blob, mem_ctx);
+	if (!pull) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = ndr_pull(pull, NDR_IN, st);
+	if (!NT_STATUS_IS_OK(status)) {
+		return ndr_pull_error(pull, NDR_ERR_VALIDATE, 
+				      "Error in input validation pull - %s",
+				      nt_errstr(status));
+	}
+
+	push = ndr_push_init_ctx(mem_ctx);
+	if (!push) {
+		return NT_STATUS_NO_MEMORY;
+	}	
+
+	status = ndr_push(push, NDR_IN, st);
+	if (!NT_STATUS_IS_OK(status)) {
+		return ndr_push_error(push, NDR_ERR_VALIDATE, 
+				      "Error in input validation push - %s",
+				      nt_errstr(status));
+	}
+
+	blob2 = ndr_push_blob(push);
+
+	if (!data_blob_equal(&blob, &blob2)) {
+		return ndr_push_error(push, NDR_ERR_VALIDATE, 
+				      "Error in input validation data - %s",
+				      nt_errstr(status));
+	}
+
+	return NT_STATUS_OK;
+}
+
+/*
+  this is a paranoid NDR input validator. For every packet we pull
+  from the wire we push it back again then pull and push it
+  again. Then we compare the raw NDR data for that to the NDR we
+  initially generated. If they don't match then we know we must have a
+  bug in either the pull or push side of our code
+*/
+static NTSTATUS dcerpc_ndr_validate_out(TALLOC_CTX *mem_ctx,
+					void *struct_ptr,
+					size_t struct_size,
+					NTSTATUS (*ndr_push)(struct ndr_push *, int, void *),
+					NTSTATUS (*ndr_pull)(struct ndr_pull *, int, void *))
+{
+	void *st;
+	struct ndr_pull *pull;
+	struct ndr_push *push;
+	NTSTATUS status;
+	DATA_BLOB blob, blob2;
+
+	st = talloc(mem_ctx, struct_size);
+	if (!st) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	memcpy(st, struct_ptr, struct_size);
+
+	push = ndr_push_init_ctx(mem_ctx);
+	if (!push) {
+		return NT_STATUS_NO_MEMORY;
+	}	
+
+	status = ndr_push(push, NDR_OUT, struct_ptr);
+	if (!NT_STATUS_IS_OK(status)) {
+		return ndr_push_error(push, NDR_ERR_VALIDATE, 
+				      "Error in output validation push - %s",
+				      nt_errstr(status));
+	}
+
+	blob = ndr_push_blob(push);
+
+	pull = ndr_pull_init_blob(&blob, mem_ctx);
+	if (!pull) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	pull->flags |= LIBNDR_FLAG_REF_ALLOC;
+	status = ndr_pull(pull, NDR_OUT, st);
+	if (!NT_STATUS_IS_OK(status)) {
+		return ndr_pull_error(pull, NDR_ERR_VALIDATE, 
+				      "Error in output validation pull - %s",
+				      nt_errstr(status));
+	}
+
+	push = ndr_push_init_ctx(mem_ctx);
+	if (!push) {
+		return NT_STATUS_NO_MEMORY;
+	}	
+
+	status = ndr_push(push, NDR_OUT, st);
+	if (!NT_STATUS_IS_OK(status)) {
+		return ndr_push_error(push, NDR_ERR_VALIDATE, 
+				      "Error in output validation push2 - %s",
+				      nt_errstr(status));
+	}
+
+	blob2 = ndr_push_blob(push);
+
+	if (!data_blob_equal(&blob, &blob2)) {
+		return ndr_push_error(push, NDR_ERR_VALIDATE, 
+				      "Error in output validation data - %s",
+				      nt_errstr(status));
+	}
+
+	return NT_STATUS_OK;
+}
+
+/*
   a useful helper function for synchronous rpc requests 
 
   this can be used when you have ndr push/pull functions in the
@@ -739,9 +872,10 @@ NTSTATUS dcerpc_request(struct dcerpc_pipe *p,
 NTSTATUS dcerpc_ndr_request(struct dcerpc_pipe *p,
 			    uint32 opnum,
 			    TALLOC_CTX *mem_ctx,
-			    NTSTATUS (*ndr_push)(struct ndr_push *, void *),
-			    NTSTATUS (*ndr_pull)(struct ndr_pull *, void *),
-			    void *struct_ptr)
+			    NTSTATUS (*ndr_push)(struct ndr_push *, int, void *),
+			    NTSTATUS (*ndr_pull)(struct ndr_pull *, int, void *),
+			    void *struct_ptr,
+			    size_t struct_size)
 {
 	struct ndr_push *push;
 	struct ndr_pull *pull;
@@ -756,7 +890,7 @@ NTSTATUS dcerpc_ndr_request(struct dcerpc_pipe *p,
 	}
 
 	/* push the structure into a blob */
-	status = ndr_push(push, struct_ptr);
+	status = ndr_push(push, NDR_IN, struct_ptr);
 	if (!NT_STATUS_IS_OK(status)) {
 		goto failed;
 	}
@@ -764,6 +898,14 @@ NTSTATUS dcerpc_ndr_request(struct dcerpc_pipe *p,
 	/* retrieve the blob */
 	request = ndr_push_blob(push);
 
+	if (p->flags & DCERPC_DEBUG_VALIDATE_IN) {
+		status = dcerpc_ndr_validate_in(mem_ctx, request, struct_size, 
+						ndr_push, ndr_pull);
+		if (!NT_STATUS_IS_OK(status)) {
+			goto failed;
+		}
+	}
+
 	DEBUG(10,("rpc request data:\n"));
 	dump_data(10, request.data, request.length);
 
@@ -783,11 +925,19 @@ NTSTATUS dcerpc_ndr_request(struct dcerpc_pipe *p,
 	dump_data(10, pull->data, pull->data_size);
 
 	/* pull the structure from the blob */
-	status = ndr_pull(pull, struct_ptr);
+	status = ndr_pull(pull, NDR_OUT, struct_ptr);
 	if (!NT_STATUS_IS_OK(status)) {
 		goto failed;
 	}
 
+	if (p->flags & DCERPC_DEBUG_VALIDATE_OUT) {
+		status = dcerpc_ndr_validate_out(mem_ctx, struct_ptr, struct_size, 
+						 ndr_push, ndr_pull);
+		if (!NT_STATUS_IS_OK(status)) {
+			goto failed;
+		}
+	}
+
 	if (pull->offset != pull->data_size) {
 		DEBUG(0,("Warning! %d unread bytes\n", pull->data_size - pull->offset));
 		status = NT_STATUS_INFO_LENGTH_MISMATCH;
diff --git a/source4/librpc/rpc/dcerpc.h b/source4/librpc/rpc/dcerpc.h
index 3f9241e9a3..65566878e3 100644
--- a/source4/librpc/rpc/dcerpc.h
+++ b/source4/librpc/rpc/dcerpc.h
@@ -53,10 +53,14 @@ struct dcerpc_pipe {
 #define DCERPC_PFC_FLAG_NOCALL  0x20
 
 /* dcerpc pipe flags */
-#define DCERPC_DEBUG_PRINT_IN 1
+#define DCERPC_DEBUG_PRINT_IN  1
 #define DCERPC_DEBUG_PRINT_OUT 2
 #define DCERPC_DEBUG_PRINT_BOTH (DCERPC_DEBUG_PRINT_IN | DCERPC_DEBUG_PRINT_OUT)
 
+#define DCERPC_DEBUG_VALIDATE_IN  4
+#define DCERPC_DEBUG_VALIDATE_OUT 8
+#define DCERPC_DEBUG_VALIDATE_BOTH (DCERPC_DEBUG_VALIDATE_IN | DCERPC_DEBUG_VALIDATE_OUT)
+
 /*
   all dcerpc packets use this structure. 
 */