freebsd-skq/sys/netgraph/ng_vjc.c
julian 0c949560a1 Divorce the kernel binary ABI version number from the message
format version number. (userland programs should not need to be
recompiled when the netgraph kernel internal ABI is changed.

Also fix modules that don;t handle the fact that a caller may not supply
a return message pointer. (benign at the moment because the calling code
checks, but that will change)
2000-12-18 20:03:32 +00:00

626 lines
16 KiB
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>
*
* $FreeBSD$
* $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_rmnode;
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_info ng_vjc_config_type_info
= NG_VJC_CONFIG_TYPE_INFO;
static const struct ng_parse_type ng_vjc_config_type = {
&ng_parse_struct_type,
&ng_vjc_config_type_info
};
/* 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_info ng_vjc_cstate_type_info = {
{
{ "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_info
};
/* 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_info ng_vjc_slcompress_type_info = {
{
{ "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_info
};
/* 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 = {
NG_ABI_VERSION,
NG_VJC_NODE_TYPE,
NULL,
ng_vjc_constructor,
ng_vjc_rcvmsg,
ng_vjc_rmnode,
ng_vjc_newhook,
NULL,
NULL,
ng_vjc_rcvdata,
ng_vjc_disconnect,
ng_vjc_cmds
};
NETGRAPH_INIT(vjc, &ng_vjc_typestruct);
/************************************************************************
NETGRAPH NODE METHODS
************************************************************************/
/*
* Create a new node
*/
static int
ng_vjc_constructor(node_p *nodep)
{
priv_p priv;
int error;
/* Allocate private structure */
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
/* Call generic node constructor */
if ((error = ng_make_node_common(&ng_vjc_typestruct, nodep))) {
FREE(priv, M_NETGRAPH);
return (error);
}
(*nodep)->private = 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 = (priv_p) node->private;
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, struct ng_mesg *msg,
const char *raddr, struct ng_mesg **rptr, hook_p lasthook)
{
const priv_p priv = (priv_p) node->private;
struct ng_mesg *resp = NULL;
int error = 0;
/* 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;
}
if (rptr)
*rptr = resp;
else if (resp)
FREE(resp, M_NETGRAPH);
done:
FREE(msg, M_NETGRAPH);
return (error);
}
/*
* Receive data
*/
static int
ng_vjc_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
{
const node_p node = hook->node;
const priv_p priv = (priv_p) node->private;
int error = 0;
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_META(meta);
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", __FUNCTION__, 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_DATA(m, meta);
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_META(meta);
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_DATA(m, meta);
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_DATA(m, meta);
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_DATA(m, meta);
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_DATA(m, meta);
return (ENXIO);
}
/* Pull up IP+TCP headers */
if ((m = ng_vjc_pulluphdrs(m, 1)) == NULL) {
NG_FREE_META(meta);
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_DATA(m, meta);
return (EINVAL);
}
hook = priv->ip;
} else if (hook == priv->vjip) /* incoming regular packet (bypass) */
hook = priv->ip;
else
panic("%s: unknown hook", __FUNCTION__);
/* Send result back out */
NG_SEND_DATA(error, hook, m, meta);
return (error);
}
/*
* Shutdown node
*/
static int
ng_vjc_rmnode(node_p node)
{
const priv_p priv = (priv_p) node->private;
node->flags |= NG_INVALID;
ng_cutlinks(node);
ng_unname(node);
bzero(priv, sizeof(*priv));
FREE(priv, M_NETGRAPH);
node->private = NULL;
ng_unref(node);
return (0);
}
/*
* Hook disconnection
*/
static int
ng_vjc_disconnect(hook_p hook)
{
const node_p node = hook->node;
const priv_p priv = node->private;
/* 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", __FUNCTION__);
/* Go away if no hooks left */
if (node->numhooks == 0)
ng_rmnode(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);
}