svn commit: r208946 - in head: share/man/man4 sys/conf sys/modules/netgraph sys/modules/netgraph/patch sys/netgraph

Andrey V. Elsukov ae at FreeBSD.org
Wed Jun 9 12:25:58 UTC 2010


Author: ae
Date: Wed Jun  9 12:25:57 2010
New Revision: 208946
URL: http://svn.freebsd.org/changeset/base/208946

Log:
  New netgraph node ng_patch(4). It performs data modification of packets
  passing through. Modifications are restricted to a subset of C language
  operations on unsigned integers of 8, 16, 32 or 64 bit size.
  These are: set to new value (=), addition (+=), subtraction (-=),
  multiplication (*=), division (/=), negation (= -), bitwise AND (&=),
  bitwise OR (|=), bitwise eXclusive OR (^=), shift left (<<=),
  shift right (>>=). Several operations are all applied to a packet
  sequentially in order they were specified by user.
  
  Submitted by:	Maxim Ignatenko <gelraen.ua at gmail.com>
  		Vadim Goncharov <vadimnuclight at tpu.ru>
  Discussed with:	net@
  Approved by:	mav (mentor)
  MFC after:	1 month

Added:
  head/share/man/man4/ng_patch.4   (contents, props changed)
  head/sys/modules/netgraph/patch/
  head/sys/modules/netgraph/patch/Makefile   (contents, props changed)
  head/sys/netgraph/ng_patch.c   (contents, props changed)
  head/sys/netgraph/ng_patch.h   (contents, props changed)
Modified:
  head/share/man/man4/Makefile
  head/sys/conf/NOTES
  head/sys/conf/files
  head/sys/conf/options
  head/sys/modules/netgraph/Makefile

Modified: head/share/man/man4/Makefile
==============================================================================
--- head/share/man/man4/Makefile	Wed Jun  9 12:06:08 2010	(r208945)
+++ head/share/man/man4/Makefile	Wed Jun  9 12:25:57 2010	(r208946)
@@ -274,6 +274,7 @@ MAN=	aac.4 \
 	ng_nat.4 \
 	ng_netflow.4 \
 	ng_one2many.4 \
+	ng_patch.4 \
 	ng_ppp.4 \
 	ng_pppoe.4 \
 	ng_pptpgre.4 \

Added: head/share/man/man4/ng_patch.4
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/share/man/man4/ng_patch.4	Wed Jun  9 12:25:57 2010	(r208946)
@@ -0,0 +1,235 @@
+.\" Copyright (c) 2010 Maxim Ignatenko <gelraen.ua at gmail.com>
+.\" Copyright (c) 2010 Vadim Goncharov <vadimnuclight at tpu.ru>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd June 9, 2010
+.Dt NG_PATCH 4
+.Os
+.Sh NAME
+.Nm ng_patch
+.Nd "trivial mbuf data modifying netgraph node type"
+.Sh SYNOPSIS
+.In netgraph/ng_patch.h
+.Sh DESCRIPTION
+The
+.Nm patch
+node performs data modification of packets passing through it.
+Modifications are restricted to a subset of C language operations
+on unsigned integers of 8, 16, 32 or 64 bit size.
+These are: set to new value (=), addition (+=), subtraction (-=),
+multiplication (*=), division (/=), negation (= -),
+bitwise AND (&=), bitwise OR (|=), bitwise eXclusive OR (^=),
+shift left (<<=), shift right (>>=).
+A negation operation is the one exception: integer is treated as signed
+and second operand (the
+.Va value )
+is not used.
+There may be several modification operations, they are all applied
+to a packet sequentially in order they were specified by user.
+Data payload of packet is viewed as array of bytes, with zero offset
+corresponding to the very first byte of packet headers, and
+.Va length
+bytes beginning from
+.Va offset
+are taken as a single integer in network byte order.
+.Sh HOOKS
+This node type has two hooks:
+.Bl -tag -width indent
+.It Va in
+Packets received on this hook are modified according to rules specified
+in config and then forwarded to
+.Ar out
+hook, if it exists and connected.
+Otherwise they are reflected back to the
+.Ar in
+hook.
+.It Va out
+Packets received on this hook are forwarded to
+.Ar in
+hook without any changes.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width indent
+.It Dv NGM_PATCH_SETCONFIG Pq Li setconfig
+This command sets the sequence of modify operations
+that will be applied to incoming data on a hook.
+The following
+.Vt "struct ng_patch_config"
+must be supplied as an argument:
+.Bd -literal -offset 4n
+struct ng_patch_op {
+	uint64_t	value;
+	uint32_t	offset;
+	uint16_t	length; /* 1,2,4 or 8 bytes */
+	uint16_t	mode;
+};
+/* Patching modes */
+#define NG_PATCH_MODE_SET	1
+#define NG_PATCH_MODE_ADD	2
+#define NG_PATCH_MODE_SUB	3
+#define NG_PATCH_MODE_MUL	4
+#define NG_PATCH_MODE_DIV	5
+#define NG_PATCH_MODE_NEG	6
+#define NG_PATCH_MODE_AND	7
+#define NG_PATCH_MODE_OR	8
+#define NG_PATCH_MODE_XOR	9
+#define NG_PATCH_MODE_SHL	10
+#define NG_PATCH_MODE_SHR	11
+
+struct ng_patch_config {
+	uint32_t	count;
+	uint32_t	csum_flags;
+	struct ng_patch_op ops[];
+};
+.Ed
+.Pp
+The
+.Va csum_flags
+can be set to any combination of CSUM_IP, CSUM_TCP, CSUM_SCTP and CSUM_UDP
+(other values are ignored) for instructing the IP stack to recalculate the
+corresponding checksum before transmitting packet on output interface.
+The
+.Nm
+node does not do any checksum correction by itself.
+.It Dv NGM_PATCH_GETCONFIG Pq Li getconfig
+This control message obtains current set of modify operations,
+returned as
+.Vt "struct ng_patch_config" .
+.It Dv NGM_PATCH_GET_STATS Pq Li getstats
+Returns node statistics as a
+.Vt "struct ng_patch_stats" .
+.It Dv NGM_PATCH_CLR_STATS Pq Li clrstats
+Clear node statistics.
+.It Dv NGM_PATCH_GETCLR_STATS Pq Li getclrstats
+This command is identical to
+.Dv NGM_PATCH_GET_STATS ,
+except that the statistics are also atomically cleared.
+.El
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh EXAMPLES
+The
+.Nm
+node allows to modify TTL and TOS/DSCP fields in IP packets.
+Suppose you have two adjacent simplex links to remote network
+(e.g.\& satellite), so that the packets expiring in between
+will generate unwanted ICMP-replies which have to go forth, not back.
+Thus you need to raise TTL of every packet entering link link by 2
+to ensure the TTL will not reach zero there.
+So you setup
+.Xr ipfw 8
+rule with
+.Cm netgraph
+action to inject packets going to other end of simplex link by the
+following
+.Xr ngctl 8
+script:
+.Bd -literal -offset 4n
+/usr/sbin/ngctl -f- <<-SEQ
+	mkpeer ipfw: patch 200 in
+	name ipfw:200 ttl_add
+	msg ttl_add: setconfig { count=1 csum_flags=1 ops=[	\e
+		{ mode=2 value=3 length=1 offset=8 } ] }
+SEQ
+/sbin/ipfw add 150 netgraph 200 ip from any to simplex.remote.net
+.Ed
+.Pp
+Here
+.Dq Li ttl_add
+node of type
+.Nm
+configured to add (mode 
+.Dv NG_PATCH_MODE_ADD )
+a
+.Va value
+of 3 to a one-byte TTL field, which is 9th byte of IP packet header.
+.Pp
+Another example would be two consecutive modifications of packet TOS
+field: say, you need to clear the
+.Dv IPTOS_THROUGHPUT
+bit and set the
+.Dv IPTOS_MINCOST
+bit.
+So you do:
+.Bd -literal -offset 4n
+/usr/sbin/ngctl -f- <<-SEQ
+	mkpeer ipfw: patch 300 in
+	name ipfw:300 tos_chg
+	msg tos_chg: setconfig { count=2 csum_flags=1 ops=[	\e
+		{ mode=7 value=0xf7 length=1 offset=1 }		\e
+		{ mode=8 value=0x02 length=1 offset=1 } ] }
+SEQ
+/sbin/ipfw add 160 netgraph 600 ip from any to any not dst-port 80
+.Ed
+.Pp
+This first does
+.Dv NG_PATCH_MODE_AND
+clearing the fourth bit and then
+.Dv NG_PATCH_MODE_OR
+setting the third bit.
+.Pp
+In both examples the
+.Va csum_flags
+field indicates that IP checksum (but not TCP or UDP checksum) should be
+recalculated before transmit.
+.Pp
+Note: one should ensure that packets are returned to ipfw after processing
+inside
+.Xr netgraph 4 ,
+by setting appropriate
+.Xr sysctl 8
+variable:
+.Bd -literal -offset 4n
+sysctl net.inet.ip.fw.one_pass=0
+.Ed
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_ipfw 4 ,
+.Xr ngctl 8
+.Sh HISTORY
+The
+.Nm
+node type was implemented in
+.Fx 8.1 .
+.Sh AUTHORS
+.An "Maxim Ignatenko" Aq gelraen.ua at gmail.com .
+This manual page was written by
+.An "Vadim Goncharov" Aq vadimnuclight at tpu.ru .
+.Sh BUGS
+Node blindly tries to apply every patching operation to each packet
+(except those which offset if greater than length of the packet),
+so be sure that you supply only the right packets to it (e.g. changing
+bytes in the ARP packets meant to be in IP header could corrupt
+them and make your machine unreachable from the network).
+.Pp
+.Em !!! WARNING !!!
+.Pp
+Output path of the IP stack assumes correct fields and lengths in the
+packets - changing them by mistake to incorrect values can cause
+unpredictable results including kernel panics.

Modified: head/sys/conf/NOTES
==============================================================================
--- head/sys/conf/NOTES	Wed Jun  9 12:06:08 2010	(r208945)
+++ head/sys/conf/NOTES	Wed Jun  9 12:25:57 2010	(r208946)
@@ -706,6 +706,7 @@ options 	NETGRAPH_MPPC_ENCRYPTION
 options 	NETGRAPH_NETFLOW
 options 	NETGRAPH_NAT
 options 	NETGRAPH_ONE2MANY
+options 	NETGRAPG_PATCH
 options 	NETGRAPH_PIPE
 options 	NETGRAPH_PPP
 options 	NETGRAPH_PPPOE

Modified: head/sys/conf/files
==============================================================================
--- head/sys/conf/files	Wed Jun  9 12:06:08 2010	(r208945)
+++ head/sys/conf/files	Wed Jun  9 12:25:57 2010	(r208946)
@@ -2470,6 +2470,7 @@ netgraph/ng_mppc.c		optional netgraph_mp
 netgraph/ng_nat.c		optional netgraph_nat inet libalias
 netgraph/ng_one2many.c		optional netgraph_one2many
 netgraph/ng_parse.c		optional netgraph
+netgraph/ng_patch.c		optional netgraph_patch
 netgraph/ng_pipe.c		optional netgraph_pipe
 netgraph/ng_ppp.c		optional netgraph_ppp
 netgraph/ng_pppoe.c		optional netgraph_pppoe

Modified: head/sys/conf/options
==============================================================================
--- head/sys/conf/options	Wed Jun  9 12:06:08 2010	(r208945)
+++ head/sys/conf/options	Wed Jun  9 12:25:57 2010	(r208946)
@@ -486,6 +486,7 @@ NETGRAPH_MPPC_ENCRYPTION	opt_netgraph.h
 NETGRAPH_NAT		opt_netgraph.h
 NETGRAPH_NETFLOW	opt_netgraph.h
 NETGRAPH_ONE2MANY	opt_netgraph.h
+NETGRAPH_PATCH		opt_netgraph.h
 NETGRAPH_PIPE		opt_netgraph.h
 NETGRAPH_PPP		opt_netgraph.h
 NETGRAPH_PPPOE		opt_netgraph.h

Modified: head/sys/modules/netgraph/Makefile
==============================================================================
--- head/sys/modules/netgraph/Makefile	Wed Jun  9 12:06:08 2010	(r208945)
+++ head/sys/modules/netgraph/Makefile	Wed Jun  9 12:25:57 2010	(r208946)
@@ -35,6 +35,7 @@ SUBDIR=	async \
 	netflow \
 	netgraph \
 	one2many \
+	patch \
 	pipe \
 	ppp \
 	pppoe \

Added: head/sys/modules/netgraph/patch/Makefile
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/modules/netgraph/patch/Makefile	Wed Jun  9 12:25:57 2010	(r208946)
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+KMOD=	ng_patch
+SRCS= 	ng_patch.c
+
+.include <bsd.kmod.mk>

Added: head/sys/netgraph/ng_patch.c
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/netgraph/ng_patch.c	Wed Jun  9 12:25:57 2010	(r208946)
@@ -0,0 +1,566 @@
+/*-
+ * Copyright (C) 2010 by Maxim Ignatenko <gelraen.ua at gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/mbuf.h>
+#include <sys/malloc.h>
+#include <sys/ctype.h>
+#include <sys/errno.h>
+#include <sys/endian.h>	/* be64toh(), htobe64() */
+#include <netgraph/ng_message.h>
+#include <netgraph/ng_parse.h>
+#include <netgraph/ng_patch.h>
+#include <netgraph/netgraph.h>
+
+static ng_constructor_t	ng_patch_constructor;
+static ng_rcvmsg_t	ng_patch_rcvmsg;
+static ng_shutdown_t	ng_patch_shutdown;
+static ng_newhook_t	ng_patch_newhook;
+static ng_rcvdata_t	ng_patch_rcvdata;
+static ng_disconnect_t	ng_patch_disconnect;
+
+#define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0))
+
+static int
+ng_patch_config_getlen(const struct ng_parse_type *type, const u_char *start,
+    const u_char *buf)
+{
+	const struct ng_patch_config *p;
+
+	p = (const struct ng_patch_config *)(buf -
+	    OFFSETOF(struct ng_patch_config, ops));
+	return (p->count);
+}
+
+static const struct ng_parse_struct_field ng_patch_op_type_fields[]
+	= NG_PATCH_OP_TYPE_INFO;
+static const struct ng_parse_type ng_patch_op_type = {
+	&ng_parse_struct_type,
+	&ng_patch_op_type_fields
+};
+
+static const struct ng_parse_array_info ng_patch_confarr_info = {
+	&ng_patch_op_type,
+	&ng_patch_config_getlen
+};
+static const struct ng_parse_type ng_patch_confarr_type = {
+	&ng_parse_array_type,
+	&ng_patch_confarr_info
+};
+
+static const struct ng_parse_struct_field ng_patch_config_type_fields[]
+	= NG_PATCH_CONFIG_TYPE_INFO;
+static const struct ng_parse_type ng_patch_config_type = {
+	&ng_parse_struct_type,
+	&ng_patch_config_type_fields
+};
+
+static const struct ng_parse_struct_field ng_patch_stats_fields[]
+	= NG_PATCH_STATS_TYPE_INFO;
+static const struct ng_parse_type ng_patch_stats_type = {
+	&ng_parse_struct_type,
+	&ng_patch_stats_fields
+};
+
+static const struct ng_cmdlist ng_patch_cmdlist[] = {
+	{
+		NGM_PATCH_COOKIE,
+		NGM_PATCH_GETCONFIG,
+		"getconfig",
+		NULL,
+		&ng_patch_config_type
+	},
+	{
+		NGM_PATCH_COOKIE,
+		NGM_PATCH_SETCONFIG,
+		"setconfig",
+		&ng_patch_config_type,
+		NULL
+	},
+	{
+		NGM_PATCH_COOKIE,
+		NGM_PATCH_GET_STATS,
+		"getstats",
+		NULL,
+		&ng_patch_stats_type
+	},
+	{
+		NGM_PATCH_COOKIE,
+		NGM_PATCH_CLR_STATS,
+		"clrstats",
+		NULL,
+		NULL
+	},
+	{
+		NGM_PATCH_COOKIE,
+		NGM_PATCH_GETCLR_STATS,
+		"getclrstats",
+		NULL,
+		&ng_patch_stats_type
+	},
+	{ 0 }
+};
+
+static struct ng_type typestruct = {
+	.version =	NG_ABI_VERSION,
+	.name =		NG_PATCH_NODE_TYPE,
+	.constructor =	ng_patch_constructor,
+	.rcvmsg =	ng_patch_rcvmsg,
+	.shutdown =	ng_patch_shutdown,
+	.newhook =	ng_patch_newhook,
+	.rcvdata =	ng_patch_rcvdata,
+	.disconnect =	ng_patch_disconnect,
+	.cmdlist =	ng_patch_cmdlist,
+};
+NETGRAPH_INIT(patch, &typestruct);
+
+union patch_val {
+	uint8_t		v1;
+	uint16_t	v2;
+	uint32_t	v4;
+	uint64_t	v8;
+};
+
+struct ng_patch_priv {
+	hook_p		in;
+	hook_p		out;
+	struct ng_patch_config *config;
+	union patch_val *val;
+	struct ng_patch_stats stats;
+};
+typedef struct ng_patch_priv *priv_p;
+
+#define NG_PATCH_CONF_SIZE(count)	(sizeof(struct ng_patch_config) + \
+		(count) * sizeof(struct ng_patch_op))
+
+static void do_patch(priv_p conf, struct mbuf *m);
+
+static int
+ng_patch_constructor(node_p node)
+{
+	priv_p privdata;
+
+	privdata = malloc(sizeof(*privdata), M_NETGRAPH, M_WAIT | M_ZERO);
+	NG_NODE_SET_PRIVATE(node, privdata);
+	privdata->in = NULL;
+	privdata->out = NULL;
+	privdata->config = NULL;
+	return (0);
+}
+
+static int
+ng_patch_newhook(node_p node, hook_p hook, const char *name)
+{
+	const priv_p privp = NG_NODE_PRIVATE(node);
+
+	if (strncmp(name, NG_PATCH_HOOK_IN, strlen(NG_PATCH_HOOK_IN)) == 0) {
+		privp->in = hook;
+	} else if (strncmp(name, NG_PATCH_HOOK_OUT,
+	    strlen(NG_PATCH_HOOK_OUT)) == 0) {
+		privp->out = hook;
+	} else
+		return (EINVAL);
+	return(0);
+}
+
+static int
+ng_patch_rcvmsg(node_p node, item_p item, hook_p lasthook)
+{
+	const priv_p privp = NG_NODE_PRIVATE(node);
+	struct ng_patch_config *conf;
+	struct ng_mesg *msg;
+	struct ng_mesg *resp = NULL;
+	int i, clear = 0;
+	int error = 0;
+
+	NGI_GET_MSG(item, msg);
+	switch (msg->header.typecookie) {
+	case NGM_PATCH_COOKIE:
+		switch (msg->header.cmd) {
+		case NGM_PATCH_GETCONFIG:
+			if (privp->config == NULL)
+				break;
+			NG_MKRESPONSE(resp, msg,
+			    NG_PATCH_CONF_SIZE(privp->config->count), M_WAIT);
+			bcopy(privp->config, resp->data,
+			    NG_PATCH_CONF_SIZE(privp->config->count));
+			break;
+		case NGM_PATCH_SETCONFIG:
+		    {
+			struct ng_patch_config *newconf;
+			union patch_val *newval;
+
+			if (msg->header.arglen < sizeof(struct ng_patch_config)) {
+				error = EINVAL;
+				break;
+			}
+
+			conf = (struct ng_patch_config *)msg->data;
+			if (msg->header.arglen < NG_PATCH_CONF_SIZE(conf->count)) {
+				error = EINVAL;
+				break;
+			}
+
+			for(i = 0; i < conf->count; i++) {
+				switch(conf->ops[i].length) {
+				case 1:
+				case 2:
+				case 4:
+				case 8:
+					break;
+				default:
+					error = EINVAL;
+					break;
+				}
+				if (error != 0)
+					break;
+			}
+
+			conf->csum_flags &= CSUM_IP | CSUM_TCP | CSUM_UDP |
+			    CSUM_SCTP;
+
+			if (error == 0) {
+				newconf = malloc(NG_PATCH_CONF_SIZE(conf->count),
+				    M_NETGRAPH, M_WAIT);
+				newval = malloc(conf->count * sizeof(union patch_val),
+				    M_NETGRAPH, M_WAIT);
+				for(i = 0; i < conf->count; i++) {
+					switch (conf->ops[i].length) {
+					case 1:
+						newval[i].v1 = conf->ops[i].value;
+						break;
+					case 2:
+						newval[i].v2 = conf->ops[i].value;
+						break;
+					case 4:
+						newval[i].v4 = conf->ops[i].value;
+						break;
+					case 8:
+						newval[i].v8 = conf->ops[i].value;
+						break;
+					}
+				}
+				bcopy(conf, newconf, NG_PATCH_CONF_SIZE(conf->count));
+				if (privp->val != NULL)
+					free(privp->val, M_NETGRAPH);
+				privp->val = newval;
+				if (privp->config != NULL)
+					free(privp->config, M_NETGRAPH);
+				privp->config = newconf;
+			}
+			break;
+		    }
+		case NGM_PATCH_GETCLR_STATS:
+			clear = 1;
+			/* FALLTHROUGH */
+		case NGM_PATCH_GET_STATS:
+			NG_MKRESPONSE(resp, msg, sizeof(struct ng_patch_stats),
+			    M_WAIT);
+			bcopy(&(privp->stats), resp->data,
+			    sizeof(struct ng_patch_stats));
+			if (clear == 0)
+				break;
+			/* else FALLTHROUGH */
+		case NGM_PATCH_CLR_STATS:
+			bzero(&(privp->stats), sizeof(struct ng_patch_stats));
+			break;
+		default:
+			error = EINVAL;
+			break;
+		}
+		break;
+	default:
+		error = EINVAL;
+		break;
+	}
+
+	NG_RESPOND_MSG(error, node, item, resp);
+	NG_FREE_MSG(msg);
+	return(error);
+}
+
+static void
+do_patch(priv_p privp, struct mbuf *m)
+{
+	struct ng_patch_config *conf = privp->config;
+	uint64_t buf;
+	int i, patched = 0;
+
+	for(i = 0; i < conf->count; i++) {
+		if (conf->ops[i].offset + conf->ops[i].length > m->m_pkthdr.len)
+			continue;
+
+		/* for "=" operation we don't need to copy data from mbuf */
+		if (conf->ops[i].mode != NG_PATCH_MODE_SET) {
+			m_copydata(m, conf->ops[i].offset,
+			    conf->ops[i].length, (caddr_t)&buf);
+		}
+		
+		switch (conf->ops[i].length) {
+		case 1:
+			switch (conf->ops[i].mode) {
+			case NG_PATCH_MODE_SET:
+				*((uint8_t *)&buf) = privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_ADD:
+				*((uint8_t *)&buf) += privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_SUB:
+				*((uint8_t *)&buf) -= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_MUL:
+				*((uint8_t *)&buf) *= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_DIV:
+				*((uint8_t *)&buf) /= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_NEG:
+				*((int8_t *)&buf) = - *((int8_t *)&buf);
+				break;
+			case NG_PATCH_MODE_AND:
+				*((uint8_t *)&buf) &= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_OR:
+				*((uint8_t *)&buf) |= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_XOR:
+				*((uint8_t *)&buf) ^= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_SHL:
+				*((uint8_t *)&buf) <<= privp->val[i].v1;
+				break;
+			case NG_PATCH_MODE_SHR:
+				*((uint8_t *)&buf) >>= privp->val[i].v1;
+				break;
+			}
+			break;
+		case 2:
+			*((int16_t *)&buf) =  ntohs(*((int16_t *)&buf));
+			switch (conf->ops[i].mode) {
+			case NG_PATCH_MODE_SET:
+				*((uint16_t *)&buf) = privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_ADD:
+				*((uint16_t *)&buf) += privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_SUB:
+				*((uint16_t *)&buf) -= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_MUL:
+				*((uint16_t *)&buf) *= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_DIV:
+				*((uint16_t *)&buf) /= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_NEG:
+				*((int16_t *)&buf) = - *((int16_t *)&buf);
+				break;
+			case NG_PATCH_MODE_AND:
+				*((uint16_t *)&buf) &= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_OR:
+				*((uint16_t *)&buf) |= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_XOR:
+				*((uint16_t *)&buf) ^= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_SHL:
+				*((uint16_t *)&buf) <<= privp->val[i].v2;
+				break;
+			case NG_PATCH_MODE_SHR:
+				*((uint16_t *)&buf) >>= privp->val[i].v2;
+				break;
+			}
+			*((int16_t *)&buf) =  htons(*((int16_t *)&buf));
+			break;
+		case 4:
+			*((int32_t *)&buf) =  ntohl(*((int32_t *)&buf));
+			switch (conf->ops[i].mode) {
+			case NG_PATCH_MODE_SET:
+				*((uint32_t *)&buf) = privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_ADD:
+				*((uint32_t *)&buf) += privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_SUB:
+				*((uint32_t *)&buf) -= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_MUL:
+				*((uint32_t *)&buf) *= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_DIV:
+				*((uint32_t *)&buf) /= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_NEG:
+				*((int32_t *)&buf) = - *((int32_t *)&buf);
+				break;
+			case NG_PATCH_MODE_AND:
+				*((uint32_t *)&buf) &= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_OR:
+				*((uint32_t *)&buf) |= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_XOR:
+				*((uint32_t *)&buf) ^= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_SHL:
+				*((uint32_t *)&buf) <<= privp->val[i].v4;
+				break;
+			case NG_PATCH_MODE_SHR:
+				*((uint32_t *)&buf) >>= privp->val[i].v4;
+				break;
+			}
+			*((int32_t *)&buf) =  htonl(*((int32_t *)&buf));
+			break;
+		case 8:
+			*((int64_t *)&buf) =  be64toh(*((int64_t *)&buf));
+			switch (conf->ops[i].mode) {
+			case NG_PATCH_MODE_SET:
+				*((uint64_t *)&buf) = privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_ADD:
+				*((uint64_t *)&buf) += privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_SUB:
+				*((uint64_t *)&buf) -= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_MUL:
+				*((uint64_t *)&buf) *= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_DIV:
+				*((uint64_t *)&buf) /= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_NEG:
+				*((int64_t *)&buf) = - *((int64_t *)&buf);
+				break;
+			case NG_PATCH_MODE_AND:
+				*((uint64_t *)&buf) &= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_OR:
+				*((uint64_t *)&buf) |= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_XOR:
+				*((uint64_t *)&buf) ^= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_SHL:
+				*((uint64_t *)&buf) <<= privp->val[i].v8;
+				break;
+			case NG_PATCH_MODE_SHR:
+				*((uint64_t *)&buf) >>= privp->val[i].v8;
+				break;
+			}
+			*((int64_t *)&buf) =  htobe64(*((int64_t *)&buf));
+			break;
+		}
+
+		m_copyback(m, conf->ops[i].offset, conf->ops[i].length,
+		    (caddr_t)&buf);
+		patched = 1;
+	}
+	if (patched > 0)
+		privp->stats.patched++;
+}
+
+static int
+ng_patch_rcvdata(hook_p hook, item_p item)
+{
+	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
+	struct mbuf *m;
+	hook_p target;
+	int error;
+
+	priv->stats.received++;
+	NGI_GET_M(item, m);
+	if (priv->config != NULL && hook == priv->in &&
+	    (m->m_flags & M_PKTHDR) != 0) {
+		m = m_unshare(m,M_NOWAIT);
+		if (m == NULL) {
+			priv->stats.dropped++;
+			NG_FREE_ITEM(item);
+			return (ENOMEM);
+		}
+		do_patch(priv, m);
+		m->m_flags |= priv->config->csum_flags;
+	}
+
+	target = NULL;
+	if (hook == priv->in) {
+		/* return frames on 'in' hook if 'out' not connected */
+		if (priv->out != NULL)
+			target = priv->out;
+		else
+			target = priv->in;
+	}
+	if (hook == priv->out && priv->in != NULL)
+		target = priv->in;
+
+	if (target == NULL) {
+		priv->stats.dropped++;
+		NG_FREE_ITEM(item);
+		NG_FREE_M(m);
+		return (0);
+	}
+	NG_FWD_NEW_DATA(error, item, target, m);
+	return (error);
+}
+
+static int
+ng_patch_shutdown(node_p node)
+{
+	const priv_p privdata = NG_NODE_PRIVATE(node);
+
+	if (privdata->val != NULL)
+		free(privdata->val, M_NETGRAPH);
+	if (privdata->config != NULL)
+		free(privdata->config, M_NETGRAPH);
+	NG_NODE_SET_PRIVATE(node, NULL);
+	NG_NODE_UNREF(node);
+	free(privdata, M_NETGRAPH);
+	return (0);
+}
+
+static int
+ng_patch_disconnect(hook_p hook)
+{
+	priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
+
+	if (hook == priv->in) {
+		priv->in = NULL;
+	}
+	if (hook == priv->out) {
+		priv->out = NULL;
+	}
+	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
+	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */
+		ng_rmnode_self(NG_HOOK_NODE(hook));
+	return (0);
+}
+

Added: head/sys/netgraph/ng_patch.h
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/netgraph/ng_patch.h	Wed Jun  9 12:25:57 2010	(r208946)
@@ -0,0 +1,107 @@
+/*-
+ * Copyright (C) 2010 by Maxim Ignatenko <gelraen.ua at gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _NETGRAPH_NG_PATCH_H_
+#define _NETGRAPH_NG_PATCH_H_
+
+/* Node type name. */
+#define NG_PATCH_NODE_TYPE	"patch"
+
+/* Node type cookie. */
+#define NGM_PATCH_COOKIE	1262445509
+
+/* Hook names */
+#define NG_PATCH_HOOK_IN	"in"
+#define NG_PATCH_HOOK_OUT	"out"
+
+/* Netgraph commands understood by this node type */
+enum {
+	NGM_PATCH_SETCONFIG = 1,
+	NGM_PATCH_GETCONFIG,
+	NGM_PATCH_GET_STATS,
+	NGM_PATCH_CLR_STATS,
+	NGM_PATCH_GETCLR_STATS
+};
+
+/* Patching modes */
+enum {
+	NG_PATCH_MODE_SET = 1,
+	NG_PATCH_MODE_ADD = 2,
+	NG_PATCH_MODE_SUB = 3,
+	NG_PATCH_MODE_MUL = 4,
+	NG_PATCH_MODE_DIV = 5,
+	NG_PATCH_MODE_NEG = 6,
+	NG_PATCH_MODE_AND = 7,
+	NG_PATCH_MODE_OR = 8,
+	NG_PATCH_MODE_XOR = 9,
+	NG_PATCH_MODE_SHL = 10,
+	NG_PATCH_MODE_SHR = 11
+};
+
+struct ng_patch_op {
+	uint64_t	value;
+	uint32_t	offset;
+	uint16_t	length;	/* 1,2,4 or 8 (bytes) */
+	uint16_t	mode;
+};
+
+#define NG_PATCH_OP_TYPE_INFO	{	\
+		{ "value",	&ng_parse_uint64_type	},	\
+		{ "offset",	&ng_parse_uint32_type	},	\
+		{ "length",	&ng_parse_uint16_type	},	\
+		{ "mode",	&ng_parse_uint16_type	},	\
+		{ NULL } \
+}
+
+struct ng_patch_config {
+	uint32_t	count;
+	uint32_t	csum_flags;
+	struct ng_patch_op ops[];
+};
+
+#define NG_PATCH_CONFIG_TYPE_INFO	{	\
+		{ "count",	&ng_parse_uint32_type	},	\
+		{ "csum_flags",	&ng_parse_uint32_type	},	\
+		{ "ops",	&ng_patch_confarr_type	},	\
+		{ NULL } \
+}
+
+struct ng_patch_stats {
+	uint64_t	received;
+	uint64_t	patched;
+	uint64_t	dropped;
+};
+
+#define NG_PATCH_STATS_TYPE_INFO {	\
+		{ "received",	&ng_parse_uint64_type	},	\
+		{ "patched",	&ng_parse_uint64_type	},	\
+		{ "dropped",	&ng_parse_uint64_type	},	\
+		{ NULL } \
+}
+
+#endif /* _NETGRAPH_NG_PATCH_H_ */


More information about the svn-src-all mailing list