FreeBSD-5.3/sys/netgraph/ng_vjc.c
/*
* ng_vjc.c
*
* 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: Archie Cobbs <archie@freebsd.org>
*
* $FreeBSD: src/sys/netgraph/ng_vjc.c,v 1.24 2004/05/29 00:51:11 julian Exp $
* $Whistle: ng_vjc.c,v 1.17 1999/11/01 09:24:52 julian Exp $
*/
/*
* This node performs Van Jacobson IP header (de)compression.
* You must have included net/slcompress.c in your kernel compilation.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_vjc.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <net/slcompress.h>
/* Check agreement with slcompress.c */
#if MAX_STATES != NG_VJC_MAX_CHANNELS
#error NG_VJC_MAX_CHANNELS must be the same as MAX_STATES
#endif
/* Maximum length of a compressed TCP VJ header */
#define MAX_VJHEADER 19
/* Node private data */
struct ng_vjc_private {
struct ngm_vjc_config conf;
struct slcompress slc;
hook_p ip;
hook_p vjcomp;
hook_p vjuncomp;
hook_p vjip;
};
typedef struct ng_vjc_private *priv_p;
#define ERROUT(x) do { error = (x); goto done; } while (0)
/* Netgraph node methods */
static ng_constructor_t ng_vjc_constructor;
static ng_rcvmsg_t ng_vjc_rcvmsg;
static ng_shutdown_t ng_vjc_shutdown;
static ng_newhook_t ng_vjc_newhook;
static ng_rcvdata_t ng_vjc_rcvdata;
static ng_disconnect_t ng_vjc_disconnect;
/* Helper stuff */
static struct mbuf *ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP);
/* Parse type for struct ngm_vjc_config */
static const struct ng_parse_struct_field ng_vjc_config_type_fields[]
= NG_VJC_CONFIG_TYPE_INFO;
static const struct ng_parse_type ng_vjc_config_type = {
&ng_parse_struct_type,
&ng_vjc_config_type_fields
};
/* Parse type for the 'last_cs' and 'cs_next' fields in struct slcompress,
which are pointers converted to integer indices, so parse them that way. */
#if _MACHINE_ARCH == i386
#define NG_VJC_TSTATE_PTR_TYPE &ng_parse_uint32_type
#elif _MACHINE_ARCH == alpha
#define NG_VJC_TSTATE_PTR_TYPE &ng_parse_uint64_type
#else
#error Unspported _MACHINE_ARCH
#endif
/* Parse type for the 'cs_hdr' field in a struct cstate. Ideally we would
like to use a 'struct ip' type instead of a simple array of bytes. */
static const struct ng_parse_fixedarray_info ng_vjc_cs_hdr_type_info = {
&ng_parse_hint8_type,
MAX_HDR
};
static const struct ng_parse_type ng_vjc_cs_hdr_type = {
&ng_parse_fixedarray_type,
&ng_vjc_cs_hdr_type_info
};
/* Parse type for a struct cstate */
static const struct ng_parse_struct_field ng_vjc_cstate_type_fields[] = {
{ "cs_next", NG_VJC_TSTATE_PTR_TYPE },
{ "cs_hlen", &ng_parse_uint16_type },
{ "cs_id", &ng_parse_uint8_type },
{ "cs_filler", &ng_parse_uint8_type },
{ "cs_hdr", &ng_vjc_cs_hdr_type },
{ NULL }
};
static const struct ng_parse_type ng_vjc_cstate_type = {
&ng_parse_struct_type,
&ng_vjc_cstate_type_fields
};
/* Parse type for an array of MAX_STATES struct cstate's, ie, tstate & rstate */
static const struct ng_parse_fixedarray_info ng_vjc_cstatearray_type_info = {
&ng_vjc_cstate_type,
MAX_STATES
};
static const struct ng_parse_type ng_vjc_cstatearray_type = {
&ng_parse_fixedarray_type,
&ng_vjc_cstatearray_type_info
};
/* Parse type for struct slcompress. Keep this in sync with the
definition of struct slcompress defined in <net/slcompress.h> */
static const struct ng_parse_struct_field ng_vjc_slcompress_type_fields[] = {
{ "last_cs", NG_VJC_TSTATE_PTR_TYPE },
{ "last_recv", &ng_parse_uint8_type },
{ "last_xmit", &ng_parse_uint8_type },
{ "flags", &ng_parse_hint16_type },
#ifndef SL_NO_STATS
{ "sls_packets", &ng_parse_uint32_type },
{ "sls_compressed", &ng_parse_uint32_type },
{ "sls_searches", &ng_parse_uint32_type },
{ "sls_misses", &ng_parse_uint32_type },
{ "sls_uncompressedin", &ng_parse_uint32_type },
{ "sls_compressedin", &ng_parse_uint32_type },
{ "sls_errorin", &ng_parse_uint32_type },
{ "sls_tossed", &ng_parse_uint32_type },
#endif
{ "tstate", &ng_vjc_cstatearray_type },
{ "rstate", &ng_vjc_cstatearray_type },
{ NULL }
};
static const struct ng_parse_type ng_vjc_slcompress_type = {
&ng_parse_struct_type,
&ng_vjc_slcompress_type_fields
};
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_vjc_cmds[] = {
{
NGM_VJC_COOKIE,
NGM_VJC_SET_CONFIG,
"setconfig",
&ng_vjc_config_type,
NULL
},
{
NGM_VJC_COOKIE,
NGM_VJC_GET_CONFIG,
"getconfig",
NULL,
&ng_vjc_config_type,
},
{
NGM_VJC_COOKIE,
NGM_VJC_GET_STATE,
"getstate",
NULL,
&ng_vjc_slcompress_type,
},
{
NGM_VJC_COOKIE,
NGM_VJC_CLR_STATS,
"clrstats",
NULL,
NULL,
},
{
NGM_VJC_COOKIE,
NGM_VJC_RECV_ERROR,
"recverror",
NULL,
NULL,
},
{ 0 }
};
/* Node type descriptor */
static struct ng_type ng_vjc_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_VJC_NODE_TYPE,
.constructor = ng_vjc_constructor,
.rcvmsg = ng_vjc_rcvmsg,
.shutdown = ng_vjc_shutdown,
.newhook = ng_vjc_newhook,
.rcvdata = ng_vjc_rcvdata,
.disconnect = ng_vjc_disconnect,
.cmdlist = ng_vjc_cmds,
};
NETGRAPH_INIT(vjc, &ng_vjc_typestruct);
/************************************************************************
NETGRAPH NODE METHODS
************************************************************************/
/*
* Create a new node
*/
static int
ng_vjc_constructor(node_p node)
{
priv_p priv;
/* Allocate private structure */
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
NG_NODE_SET_PRIVATE(node, priv);
/* Done */
return (0);
}
/*
* Add a new hook
*/
static int
ng_vjc_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
hook_p *hookp;
/* Get hook */
if (strcmp(name, NG_VJC_HOOK_IP) == 0)
hookp = &priv->ip;
else if (strcmp(name, NG_VJC_HOOK_VJCOMP) == 0)
hookp = &priv->vjcomp;
else if (strcmp(name, NG_VJC_HOOK_VJUNCOMP) == 0)
hookp = &priv->vjuncomp;
else if (strcmp(name, NG_VJC_HOOK_VJIP) == 0)
hookp = &priv->vjip;
else
return (EINVAL);
/* See if already connected */
if (*hookp)
return (EISCONN);
/* OK */
*hookp = hook;
return (0);
}
/*
* Receive a control message
*/
static int
ng_vjc_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
NGI_GET_MSG(item, msg);
/* Check type cookie */
switch (msg->header.typecookie) {
case NGM_VJC_COOKIE:
switch (msg->header.cmd) {
case NGM_VJC_SET_CONFIG:
{
struct ngm_vjc_config *const c =
(struct ngm_vjc_config *) msg->data;
if (msg->header.arglen != sizeof(*c))
ERROUT(EINVAL);
if ((priv->conf.enableComp || priv->conf.enableDecomp)
&& (c->enableComp || c->enableDecomp))
ERROUT(EALREADY);
if (c->enableComp) {
if (c->maxChannel > NG_VJC_MAX_CHANNELS - 1
|| c->maxChannel < NG_VJC_MIN_CHANNELS - 1)
ERROUT(EINVAL);
} else
c->maxChannel = NG_VJC_MAX_CHANNELS - 1;
if (c->enableComp != 0 || c->enableDecomp != 0) {
bzero(&priv->slc, sizeof(priv->slc));
sl_compress_init(&priv->slc, c->maxChannel);
}
priv->conf = *c;
break;
}
case NGM_VJC_GET_CONFIG:
{
struct ngm_vjc_config *conf;
NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
conf = (struct ngm_vjc_config *)resp->data;
*conf = priv->conf;
break;
}
case NGM_VJC_GET_STATE:
{
const struct slcompress *const sl0 = &priv->slc;
struct slcompress *sl;
u_int16_t index;
int i;
/* Get response structure */
NG_MKRESPONSE(resp, msg, sizeof(*sl), M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
sl = (struct slcompress *)resp->data;
*sl = *sl0;
/* Replace pointers with integer indicies */
if (sl->last_cs != NULL) {
index = sl0->last_cs - sl0->tstate;
bzero(&sl->last_cs, sizeof(sl->last_cs));
*((u_int16_t *)&sl->last_cs) = index;
}
for (i = 0; i < MAX_STATES; i++) {
struct cstate *const cs = &sl->tstate[i];
index = sl0->tstate[i].cs_next - sl0->tstate;
bzero(&cs->cs_next, sizeof(cs->cs_next));
*((u_int16_t *)&cs->cs_next) = index;
}
break;
}
case NGM_VJC_CLR_STATS:
priv->slc.sls_packets = 0;
priv->slc.sls_compressed = 0;
priv->slc.sls_searches = 0;
priv->slc.sls_misses = 0;
priv->slc.sls_uncompressedin = 0;
priv->slc.sls_compressedin = 0;
priv->slc.sls_errorin = 0;
priv->slc.sls_tossed = 0;
break;
case NGM_VJC_RECV_ERROR:
sl_uncompress_tcp(NULL, 0, TYPE_ERROR, &priv->slc);
break;
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive data
*/
static int
ng_vjc_rcvdata(hook_p hook, item_p item)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
int error = 0;
struct mbuf *m;
NGI_GET_M(item, m);
if (hook == priv->ip) { /* outgoing packet */
u_int type = TYPE_IP;
/* Compress packet if enabled and proto is TCP */
if (priv->conf.enableComp) {
struct ip *ip;
if ((m = ng_vjc_pulluphdrs(m, 0)) == NULL) {
NG_FREE_ITEM(item);
return (ENOBUFS);
}
ip = mtod(m, struct ip *);
if (ip->ip_p == IPPROTO_TCP) {
const int origLen = m->m_len;
type = sl_compress_tcp(m, ip,
&priv->slc, priv->conf.compressCID);
m->m_pkthdr.len += m->m_len - origLen;
}
}
/* Dispatch to the appropriate outgoing hook */
switch (type) {
case TYPE_IP:
hook = priv->vjip;
break;
case TYPE_UNCOMPRESSED_TCP:
hook = priv->vjuncomp;
break;
case TYPE_COMPRESSED_TCP:
hook = priv->vjcomp;
break;
default:
panic("%s: type=%d", __func__, type);
}
} else if (hook == priv->vjcomp) { /* incoming compressed packet */
int vjlen, need2pullup;
struct mbuf *hm;
u_char *hdr;
u_int hlen;
/* Are we decompressing? */
if (!priv->conf.enableDecomp) {
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (ENXIO);
}
/* Pull up the necessary amount from the mbuf */
need2pullup = MAX_VJHEADER;
if (need2pullup > m->m_pkthdr.len)
need2pullup = m->m_pkthdr.len;
if (m->m_len < need2pullup
&& (m = m_pullup(m, need2pullup)) == NULL) {
priv->slc.sls_errorin++;
NG_FREE_ITEM(item);
return (ENOBUFS);
}
/* Uncompress packet to reconstruct TCP/IP header */
vjlen = sl_uncompress_tcp_core(mtod(m, u_char *),
m->m_len, m->m_pkthdr.len, TYPE_COMPRESSED_TCP,
&priv->slc, &hdr, &hlen);
if (vjlen <= 0) {
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (EINVAL);
}
m_adj(m, vjlen);
/* Copy the reconstructed TCP/IP headers into a new mbuf */
MGETHDR(hm, M_DONTWAIT, MT_DATA);
if (hm == NULL) {
priv->slc.sls_errorin++;
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (ENOBUFS);
}
hm->m_len = 0;
hm->m_pkthdr.rcvif = NULL;
if (hlen > MHLEN) { /* unlikely, but can happen */
MCLGET(hm, M_DONTWAIT);
if ((hm->m_flags & M_EXT) == 0) {
m_freem(hm);
priv->slc.sls_errorin++;
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (ENOBUFS);
}
}
bcopy(hdr, mtod(hm, u_char *), hlen);
hm->m_len = hlen;
/* Glue TCP/IP headers and rest of packet together */
hm->m_next = m;
hm->m_pkthdr.len = hlen + m->m_pkthdr.len;
m = hm;
hook = priv->ip;
} else if (hook == priv->vjuncomp) { /* incoming uncompressed pkt */
u_char *hdr;
u_int hlen;
/* Are we decompressing? */
if (!priv->conf.enableDecomp) {
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (ENXIO);
}
/* Pull up IP+TCP headers */
if ((m = ng_vjc_pulluphdrs(m, 1)) == NULL) {
NG_FREE_ITEM(item);
return (ENOBUFS);
}
/* Run packet through uncompressor */
if (sl_uncompress_tcp_core(mtod(m, u_char *),
m->m_len, m->m_pkthdr.len, TYPE_UNCOMPRESSED_TCP,
&priv->slc, &hdr, &hlen) < 0) {
NG_FREE_M(m);
NG_FREE_ITEM(item);
return (EINVAL);
}
hook = priv->ip;
} else if (hook == priv->vjip) /* incoming regular packet (bypass) */
hook = priv->ip;
else
panic("%s: unknown hook", __func__);
/* Send result back out */
NG_FWD_NEW_DATA(error, item, hook, m);
return (error);
}
/*
* Shutdown node
*/
static int
ng_vjc_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
bzero(priv, sizeof(*priv));
FREE(priv, M_NETGRAPH);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node);
return (0);
}
/*
* Hook disconnection
*/
static int
ng_vjc_disconnect(hook_p hook)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
/* Zero out hook pointer */
if (hook == priv->ip)
priv->ip = NULL;
else if (hook == priv->vjcomp)
priv->vjcomp = NULL;
else if (hook == priv->vjuncomp)
priv->vjuncomp = NULL;
else if (hook == priv->vjip)
priv->vjip = NULL;
else
panic("%s: unknown hook", __func__);
/* Go away if no hooks left */
if ((NG_NODE_NUMHOOKS(node) == 0)
&& (NG_NODE_IS_VALID(node)))
ng_rmnode_self(node);
return (0);
}
/************************************************************************
HELPER STUFF
************************************************************************/
/*
* Pull up the full IP and TCP headers of a packet. If packet is not
* a TCP packet, just pull up the IP header.
*/
static struct mbuf *
ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP)
{
struct ip *ip;
struct tcphdr *tcp;
int ihlen, thlen;
if (m->m_len < sizeof(*ip) && (m = m_pullup(m, sizeof(*ip))) == NULL)
return (NULL);
ip = mtod(m, struct ip *);
if (!knownTCP && ip->ip_p != IPPROTO_TCP)
return (m);
ihlen = ip->ip_hl << 2;
if (m->m_len < ihlen + sizeof(*tcp)) {
if ((m = m_pullup(m, ihlen + sizeof(*tcp))) == NULL)
return (NULL);
ip = mtod(m, struct ip *);
}
tcp = (struct tcphdr *)((u_char *)ip + ihlen);
thlen = tcp->th_off << 2;
if (m->m_len < ihlen + thlen)
m = m_pullup(m, ihlen + thlen);
return (m);
}