Whistle's Netgraph link-layer (sometimes more) networking infrastructure.

Been in production for 3 years now. Gives Instant Frame relay to if_sr
and if_ar drivers, and PPPOE support soon. See:
ftp://ftp.whistle.com/pub/archie/netgraph/index.html
for on-line manual pages.

Reviewed by: Doug Rabson (dfr@freebsd.org)
Obtained from:  Whistle CVS tree

1 files changed, 255 insertions, 0 deletions

diff --git a/sys/netgraph/netgraph.h b/sys/netgraph/netgraph.h
new file mode 100644
index 000000000000..e5e04e66da36
--- /dev/null
+++ b/sys/netgraph/netgraph.h
@@ -0,0 +1,255 @@
+
+/*
+ * netgraph.h
+ *
+ * Copyright (c) 1996-1999 Whistle Communications, Inc.
+ * All rights reserved.
+ * 
+ * Subject to the following obligations and disclaimer of warranty, use and
+ * redistribution of this software, in source or object code forms, with or
+ * without modifications are expressly permitted by Whistle Communications;
+ * provided, however, that:
+ * 1. Any and all reproductions of the source or object code must include the
+ *    copyright notice above and the following disclaimer of warranties; and
+ * 2. No rights are granted, in any manner or form, to use Whistle
+ *    Communications, Inc. trademarks, including the mark "WHISTLE
+ *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+ *    such appears in the above copyright notice or in the software.
+ * 
+ * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+ * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+ * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+ * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+ * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+ * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+ * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+ * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+ * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+ * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+ * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Julian Elischer <julian@whistle.com>
+ *
+ * $FreeBSD$
+ * $Whistle: netgraph.h,v 1.24 1999/01/28 23:54:52 julian Exp $
+ */
+
+#ifndef _NETGRAPH_NETGRAPH_H_
+#define _NETGRAPH_NETGRAPH_H_ 1
+
+#include <sys/queue.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+
+#ifndef KERNEL
+#error "This file should not be included in user level programs"
+#endif
+
+/*
+ * Structure of a hook
+ */
+struct ng_hook {
+	char   *name;		/* what this node knows this link as */
+	void   *private;	/* node dependant ID for this hook */
+	int	flags;		/* info about this hook/link */
+	int	refs;		/* dont actually free this till 0 */
+	struct	ng_hook *peer;	/* the other end of this link */
+	struct	ng_node *node;	/* The node this hook is attached to */
+	LIST_ENTRY(ng_hook) hooks;	/* linked list of all hooks on node */
+};
+typedef struct ng_hook *hook_p;
+
+/* Flags for a hook */
+#define HK_INVALID		0x0001	/* don't trust it! */
+
+/*
+ * Structure of a node
+ */
+struct ng_node {
+	char   *name;		/* optional globally unique name */
+	struct	ng_type *type;	/* the installed 'type' */
+	int	flags;		/* see below for bit definitions */
+	int	sleepers;	/* #procs sleeping on this node */
+	int	refs;		/* number of references to this node */
+	int	numhooks;	/* number of hooks */
+	int	colour;		/* for graph colouring algorithms */
+	void   *private;	/* node type dependant node ID */
+	LIST_HEAD(hooks, ng_hook) hooks;	/* linked list of node hooks */
+	LIST_ENTRY(ng_node)	  nodes;	/* linked list of all nodes */
+};
+typedef struct ng_node *node_p;
+
+/* Flags for a node */
+#define NG_INVALID	0x001	/* free when all sleepers and refs go to 0 */
+#define NG_BUSY		0x002	/* callers should sleep or wait */
+#define NG_TOUCHED	0x004	/* to avoid cycles when 'flooding' */
+#define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
+#define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
+#define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
+#define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
+
+/*
+ * The structure that holds meta_data about a data packet (e.g. priority)
+ * Nodes might add or subtract options as needed if there is room.
+ * They might reallocate the struct to make more room if they need to.
+ * Meta-data is still experimental.
+ */
+struct meta_field_header {
+	u_long	cookie;		/* cookie for the field. Skip fields you don't
+				 * know about (same cookie as in messgaes) */
+	u_short type;		/* field ID */
+	u_short len;		/* total len of this field including extra
+				 * data */
+	char	data[0];	/* data starts here */
+};
+
+/* To zero out an option 'in place' set it's cookie to this */
+#define INVALID_COOKIE 865455152
+
+/* This part of the metadata is always present if the pointer is non NULL */
+struct ng_meta {
+	char	priority;	/* -ve is less priority,  0 is default */
+	char	discardability; /* higher is less valuable.. discard first */
+	u_short allocated_len;	/* amount malloc'd */
+	u_short used_len;	/* sum of all fields, options etc. */
+	u_short flags;		/* see below.. generic flags */
+	struct meta_field_header options[0];	/* add as (if) needed */
+};
+typedef struct ng_meta *meta_p;
+
+/* Flags for meta-data */
+#define NGMF_TEST	0x01	/* discard at the last moment before sending */
+#define NGMF_TRACE	0x02	/* trace when handing this data to a node */
+
+/*
+ * Structure of a node type
+ */
+struct ng_type {
+
+	/* Netgraph version number (must equal NG_VERSION) */
+	u_int32_t version;
+
+	/* Unique type name */
+	const	char *name;
+
+	/* Module event handler (optional) */
+	modeventhand_t	mod_event;
+
+	/* Node constructor */
+	int	(*constructor)(node_p *node);
+
+	/* Calls using the node */
+	int	(*rcvmsg)(node_p node, struct ng_mesg *msg,
+				const char *retaddr, struct ng_mesg **resp);
+	int	(*shutdown)(node_p node);
+	int	(*newhook)(node_p node, hook_p hook, const char *name);
+	hook_p	(*findhook)(node_p node, const char *name);
+
+	/* Calls using the hook */
+	int	(*connect)(hook_p hook);	/* already linked in */
+	int	(*rcvdata)(hook_p hook, struct mbuf *m, meta_p meta);
+	int	(*rcvdataq)(hook_p hook, struct mbuf *m, meta_p meta);
+	int	(*disconnect)(hook_p hook);	/* notify on disconnect */
+
+	/* These are private to the base netgraph code */
+	LIST_ENTRY(ng_type) types;		/* linked list of all types */
+	int		    refs;		/* number of instances */
+};
+
+/* Send data packet with meta-data */
+#define NG_SEND_DATA(error, hook, m, a)					\
+	do {								\
+		(error) = ng_send_data((hook), (m), (a));		\
+		(m) = NULL;						\
+		(a) = NULL;						\
+	} while (0)
+
+/* Send  queued data packet with meta-data */
+#define NG_SEND_DATAQ(error, hook, m, a)				\
+	do {								\
+		(error) = ng_send_dataq((hook), (m), (a));		\
+		(m) = NULL;						\
+		(a) = NULL;						\
+	} while (0)
+
+/* Free metadata */
+#define NG_FREE_META(a)							\
+	do {								\
+		if ((a)) {						\
+			FREE((a), M_NETGRAPH);				\
+			a = NULL;					\
+		}							\
+	} while (0)
+
+/* Free any data packet and/or meta-data */
+#define NG_FREE_DATA(m, a)						\
+	do {								\
+		if ((m)) {						\
+			m_freem((m));					\
+			m = NULL;					\
+		}							\
+		NG_FREE_META((a));					\
+	} while (0)
+
+/*
+ * Use the NETGRAPH_INIT() macro to link a node type into the
+ * netgraph system. This works for types compiled into the kernel
+ * as well as KLD modules. The first argument should be the type
+ * name (eg, echo) and the second a pointer to the type struct.
+ *
+ * If a different link time is desired, e.g., a device driver that
+ * needs to install its netgraph type before probing, use the
+ * NETGRAPH_INIT_ORDERED() macro instead. Deivce drivers probably
+ * want to use SI_SUB_DRIVERS instead of SI_SUB_PSEUDO.
+ */
+
+#define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
+static moduledata_t ng_##typename##_mod = {				\
+	"ng_" #typename,						\
+	ng_mod_event,							\
+	(typestructp)							\
+};									\
+DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order)
+
+#define NETGRAPH_INIT(tn, tp)						\
+	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_ANY)
+
+/* Special malloc() type for netgraph structs and ctrl messages */
+MALLOC_DECLARE(M_NETGRAPH);
+
+void	ng_cutlinks(node_p node);
+int	ng_con_nodes(node_p node,
+	     const char *name, node_p node2, const char *name2);
+void	ng_destroy_hook(hook_p hook);
+node_p	ng_findname(node_p node, const char *name);
+struct	ng_type *ng_findtype(const char *type);
+int	ng_make_node(const char *type, node_p *nodepp);
+int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
+int	ng_mkpeer(node_p node, const char *name, const char *name2, char *type);
+int	ng_mod_event(module_t mod, int what, void *arg);
+int	ng_name_node(node_p node, const char *name);
+int	ng_newtype(struct ng_type *tp);
+int	ng_path2node(node_p here, const char *path, node_p *dest, char **rtnp);
+int	ng_path_parse(char *addr, char **node, char **path, char **hook);
+int	ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta);
+int	ng_queue_msg(node_p here, struct ng_mesg *msg, int len,
+	     const char *address);
+void	ng_release_node(node_p node);
+void	ng_rmnode(node_p node);
+int	ng_send_data(hook_p hook, struct mbuf *m, meta_p meta);
+int	ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta);
+int	ng_send_msg(node_p here, struct ng_mesg *msg,
+	    const char *address, struct ng_mesg **resp);
+void	ng_unname(node_p node);
+void	ng_unref(node_p node);
+int	ng_bypass(hook_p hook1, hook_p hook2);
+int	ng_wait_node(node_p node, char *msg);
+
+#endif /* _NETGRAPH_NETGRAPH_H_ */
+