r3081: several updates to ntvfs and server side async request handling in

preparation for the full share modes and ntcreatex code that I am
working on.

highlights include:

 - changed the way a backend determines if it is allowed to process a
   request asynchronously. The previous method of looking at the
   send_fn caused problems when an intermediate ntvfs module disabled
   it, and the caller then wanted to finished processing using this
   function. The new method is a REQ_CONTROL_MAY_ASYNC flag in
   req->control_flags, which is also a bit easier to read

 - fixed 2 bugs in the readbraw server code. One related to trying to
   answer a readbraw with smb signing (which can't work, and crashed
   our signing code), the second related to error handling, which
   attempted to send a normal SMB error packet, when readbraw must
   send a 0 read reply (as it has no header)

 - added several more ntvfs_generic.c generic mapping functions. This
   means that backends no longer need to implement such esoteric
   functions as SMBwriteunlock() if they don't want to. The backend
   can just request the mapping layer turn it into a write followed by
   an unlock. This makes the backends considerably simpler as they
   only need to implement one style of each function for lock, read,
   write, open etc, rather than the full host of functions that SMB
   provides. A backend can still choose to implement them
   individually, of course, and the CIFS backend does that.

 - simplified the generic structures to make them identical to the
   principal call for several common SMB calls (such as
   RAW_WRITE_GENERIC now being an alias for RAW_WRITE_WRITEX).

 - started rewriting the pvfs_open() code in preparation for the full
   ntcreatex semantics.

 - in pvfs_open and ipc_open, initially allocate the open file
   structure as a child of the request, so on error we don't need to
   clean up. Then when we are going to succeed the open steal the
   pointer into the long term backend context. This makes for much
   simpler error handling (and fixes some bugs)

 - use a destructor in the ipc backend to make sure that everthing is
   cleaned up on receive error conditions.

 - switched the ipc backend to using idtree for fnum allocation

 - in the ntvfs_generic mapping routines, use a allocated secondary
   structure not a stack structure to ensure the request pointer
   remains valid even if the backend replies async.
(This used to be commit 3457c1836c09c82956697eb21627dfa2ed37682e)

1 files changed, 53 insertions, 118 deletions

diff --git a/source4/ntvfs/ipc/vfs_ipc.c b/source4/ntvfs/ipc/vfs_ipc.c
index 760cf07100..f4eb007235 100644
--- a/source4/ntvfs/ipc/vfs_ipc.c
+++ b/source4/ntvfs/ipc/vfs_ipc.c
@@ -31,13 +31,12 @@
    ipc$ connection. It needs to keep information about all open
    pipes */
 struct ipc_private {
-
-	uint16_t next_fnum;
-	uint16_t num_open;
+	void *idtree_fnum;
 
 	/* a list of open pipes */
 	struct pipe_state {
 		struct pipe_state *next, *prev;
+		struct ipc_private *private;
 		const char *pipe_name;
 		uint16_t fnum;
 		struct dcesrv_connection *dce_conn;
@@ -55,55 +54,11 @@ struct ipc_private {
 
 
 /*
-  find the next fnum available on this connection
-*/
-static uint16_t find_next_fnum(struct ipc_private *ipc)
-{
-	struct pipe_state *p;
-	uint32_t ret;
-
-	if (ipc->num_open == 0xFFFF) {
-		return 0;
-	}
-
-again:
-	ret = ipc->next_fnum++;
-
-	for (p=ipc->pipe_list; p; p=p->next) {
-		if (p->fnum == ret) {
-			goto again;
-		}
-	}
-
-	return ret;
-}
-
-
-/*
-  shutdown a single pipe. Called on a close or disconnect
-*/
-static void pipe_shutdown(struct ipc_private *private, struct pipe_state *p)
-{
-	talloc_free(p->dce_conn);
-	DLIST_REMOVE(private->pipe_list, p);
-	talloc_destroy(p);
-}
-
-
-/*
   find a open pipe give a file descriptor
 */
 static struct pipe_state *pipe_state_find(struct ipc_private *private, uint16_t fnum)
 {
-	struct pipe_state *p;
-	
-	for (p=private->pipe_list; p; p=p->next) {
-		if (p->fnum == fnum) {
-			return p;
-		}
-	}
-
-	return NULL;
+	return idr_find(private->idtree_fnum, fnum);
 }
 
 
@@ -127,8 +82,11 @@ static NTSTATUS ipc_connect(struct ntvfs_module_context *ntvfs,
 	ntvfs->private_data = private;
 
 	private->pipe_list = NULL;
-	private->next_fnum = 1;
-	private->num_open = 0;
+
+	private->idtree_fnum = idr_init(private);
+	if (private->idtree_fnum == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
 
 	return NT_STATUS_OK;
 }
@@ -143,7 +101,7 @@ static NTSTATUS ipc_disconnect(struct ntvfs_module_context *ntvfs,
 
 	/* close any pipes that are open. Discard any unread data */
 	while (private->pipe_list) {
-		pipe_shutdown(private, private->pipe_list);
+		talloc_free(private->pipe_list);
 	}
 
 	return NT_STATUS_OK;
@@ -196,6 +154,18 @@ static NTSTATUS ipc_setpathinfo(struct ntvfs_module_context *ntvfs,
 }
 
 
+/*
+  destroy a open pipe structure
+*/
+static int ipc_fd_destructor(void *ptr)
+{
+	struct pipe_state *p = ptr;
+	idr_remove(p->private->idtree_fnum, p->fnum);
+	DLIST_REMOVE(p->private->pipe_list, p);
+	talloc_free(p->dce_conn);
+	return 0;
+}
+
 
 /*
   open a file backend - used for MSRPC pipes
@@ -209,8 +179,9 @@ static NTSTATUS ipc_open_generic(struct ntvfs_module_context *ntvfs,
 	struct dcesrv_ep_description ep_description;
 	struct auth_session_info *session_info = NULL;
 	struct ipc_private *private = ntvfs->private_data;
+	int fnum;
 
-	p = talloc_p(private, struct pipe_state);
+	p = talloc_p(req, struct pipe_state);
 	if (!p) {
 		return NT_STATUS_NO_MEMORY;
 	}
@@ -219,16 +190,15 @@ static NTSTATUS ipc_open_generic(struct ntvfs_module_context *ntvfs,
 
 	p->pipe_name = talloc_asprintf(p, "\\pipe\\%s", fname);
 	if (!p->pipe_name) {
-		talloc_free(p);
 		return NT_STATUS_NO_MEMORY;
 	}
 
-	p->fnum = find_next_fnum(private);
-	if (p->fnum == 0) {
-		talloc_free(p);
+	fnum = idr_get_new(private->idtree_fnum, p, UINT16_MAX);
+	if (fnum == -1) {
 		return NT_STATUS_TOO_MANY_OPENED_FILES;
 	}
 
+	p->fnum = fnum;
 	p->ipc_state = 0x5ff;
 
 	/*
@@ -241,8 +211,6 @@ static NTSTATUS ipc_open_generic(struct ntvfs_module_context *ntvfs,
 	  will need to do that once the credentials infrastructure is
 	  finalised for Samba4
 	*/
-
-	printf("FINDING: %s\n", p->pipe_name);
 	ep_description.type = ENDPOINT_SMB;
 	ep_description.info.smb_pipe = p->pipe_name;
 
@@ -250,7 +218,6 @@ static NTSTATUS ipc_open_generic(struct ntvfs_module_context *ntvfs,
 	if (req->session) {
 		/* The session info is refcount-increased in the 
 		   dcesrv_endpoint_search_connect() function */
-
 		session_info = req->session->session_info;
 	}
 
@@ -259,19 +226,22 @@ static NTSTATUS ipc_open_generic(struct ntvfs_module_context *ntvfs,
 						session_info,
 						&p->dce_conn);
 	if (!NT_STATUS_IS_OK(status)) {
-		talloc_free(p);
+		idr_remove(private->idtree_fnum, p->fnum);
 		return status;
 	}
 
-	private->num_open++;
-
 	DLIST_ADD(private->pipe_list, p);
 
 	p->smbpid = req->smbpid;
 	p->session = req->session;
+	p->private = private;
 
 	*ps = p;
 
+	talloc_steal(private, p);
+
+	talloc_set_destructor(p, ipc_fd_destructor);
+
 	return NT_STATUS_OK;
 }
 
@@ -390,21 +360,14 @@ static NTSTATUS ipc_read(struct ntvfs_module_context *ntvfs,
 	struct pipe_state *p;
 	NTSTATUS status;
 
-	switch (rd->generic.level) {
-	case RAW_READ_READ:
-		fnum = rd->read.in.fnum;
-		data.length = rd->read.in.count;
-		data.data = rd->read.out.data;
-		break;
-	case RAW_READ_READX:
-		fnum = rd->readx.in.fnum;
-		data.length = rd->readx.in.maxcnt;
-		data.data = rd->readx.out.data;
-		break;
-	default:
-		return NT_STATUS_NOT_SUPPORTED;
+	if (rd->generic.level != RAW_READ_GENERIC) {
+		return ntvfs_map_read(req, rd, ntvfs);
 	}
 
+	fnum = rd->readx.in.fnum;
+	data.length = rd->readx.in.maxcnt;
+	data.data = rd->readx.out.data;
+
 	p = pipe_state_find(private, fnum);
 	if (!p) {
 		return NT_STATUS_INVALID_HANDLE;
@@ -415,18 +378,9 @@ static NTSTATUS ipc_read(struct ntvfs_module_context *ntvfs,
 		return status;
 	}
 
-	switch (rd->generic.level) {
-	case RAW_READ_READ:
-		rd->read.out.nread = data.length;
-		break;
-	case RAW_READ_READX:
-		rd->readx.out.remaining = 0;
-		rd->readx.out.compaction_mode = 0;
-		rd->readx.out.nread = data.length;
-		break;
-	default:
-		return NT_STATUS_NOT_SUPPORTED;
-	}
+	rd->readx.out.remaining = 0;
+	rd->readx.out.compaction_mode = 0;
+	rd->readx.out.nread = data.length;
 
 	return status;
 }
@@ -443,23 +397,14 @@ static NTSTATUS ipc_write(struct ntvfs_module_context *ntvfs,
 	struct pipe_state *p;
 	NTSTATUS status;
 
-	switch (wr->generic.level) {
-	case RAW_WRITE_WRITE:
-		fnum = wr->write.in.fnum;
-		data.data = discard_const_p(void, wr->write.in.data);
-		data.length = wr->write.in.count;
-		break;
-
-	case RAW_WRITE_WRITEX:
-		fnum = wr->writex.in.fnum;
-		data.data = discard_const_p(void, wr->writex.in.data);
-		data.length = wr->writex.in.count;
-		break;
-
-	default:
-		return NT_STATUS_NOT_SUPPORTED;
+	if (wr->generic.level != RAW_WRITE_GENERIC) {
+		return ntvfs_map_write(req, wr, ntvfs);
 	}
 
+	fnum = wr->writex.in.fnum;
+	data.data = discard_const_p(void, wr->writex.in.data);
+	data.length = wr->writex.in.count;
+
 	p = pipe_state_find(private, fnum);
 	if (!p) {
 		return NT_STATUS_INVALID_HANDLE;
@@ -470,17 +415,8 @@ static NTSTATUS ipc_write(struct ntvfs_module_context *ntvfs,
 		return status;
 	}
 
-	switch (wr->generic.level) {
-	case RAW_WRITE_WRITE:
-		wr->write.out.nwritten = data.length;
-		break;
-	case RAW_WRITE_WRITEX:
-		wr->writex.out.nwritten = data.length;
-		wr->writex.out.remaining = 0;
-		break;
-	default:
-		return NT_STATUS_NOT_SUPPORTED;
-	}
+	wr->writex.out.nwritten = data.length;
+	wr->writex.out.remaining = 0;
 
 	return NT_STATUS_OK;
 }
@@ -513,7 +449,7 @@ static NTSTATUS ipc_close(struct ntvfs_module_context *ntvfs,
 	struct pipe_state *p;
 
 	if (io->generic.level != RAW_CLOSE_CLOSE) {
-		return NT_STATUS_ACCESS_DENIED;
+		return ntvfs_map_close(req, io, ntvfs);
 	}
 
 	p = pipe_state_find(private, io->close.in.fnum);
@@ -521,8 +457,7 @@ static NTSTATUS ipc_close(struct ntvfs_module_context *ntvfs,
 		return NT_STATUS_INVALID_HANDLE;
 	}
 
-	pipe_shutdown(private, p);
-	private->num_open--;
+	talloc_free(p);
 
 	return NT_STATUS_OK;
 }
@@ -539,7 +474,7 @@ static NTSTATUS ipc_exit(struct ntvfs_module_context *ntvfs,
 	for (p=private->pipe_list; p; p=next) {
 		next = p->next;
 		if (p->smbpid == req->smbpid) {
-			pipe_shutdown(private, p);
+			talloc_free(p);
 		}
 	}
 
@@ -558,7 +493,7 @@ static NTSTATUS ipc_logoff(struct ntvfs_module_context *ntvfs,
 	for (p=private->pipe_list; p; p=next) {
 		next = p->next;
 		if (p->session == req->session) {
-			pipe_shutdown(private, p);
+			talloc_free(p);
 		}
 	}