/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2006 Alexander Motin <mav@alkar.net>
* 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 unmodified, 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.
*/
/*
* Deflate PPP compression netgraph node type.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/endian.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <contrib/zlib/zlib.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_deflate.h>
#include "opt_netgraph.h"
static MALLOC_DEFINE(M_NETGRAPH_DEFLATE, "netgraph_deflate",
"netgraph deflate node");
/* DEFLATE header length */
#define DEFLATE_HDRLEN 2
#define PROT_COMPD 0x00fd
#define DEFLATE_BUF_SIZE 4096
/* Node private data */
struct ng_deflate_private {
struct ng_deflate_config cfg; /* configuration */
u_char inbuf[DEFLATE_BUF_SIZE]; /* input buffer */
u_char outbuf[DEFLATE_BUF_SIZE]; /* output buffer */
z_stream cx; /* compression context */
struct ng_deflate_stats stats; /* statistics */
ng_ID_t ctrlnode; /* path to controlling node */
uint16_t seqnum; /* sequence number */
u_char compress; /* compress/decompress flag */
};
typedef struct ng_deflate_private *priv_p;
/* Netgraph node methods */
static ng_constructor_t ng_deflate_constructor;
static ng_rcvmsg_t ng_deflate_rcvmsg;
static ng_shutdown_t ng_deflate_shutdown;
static ng_newhook_t ng_deflate_newhook;
static ng_rcvdata_t ng_deflate_rcvdata;
static ng_disconnect_t ng_deflate_disconnect;
/* Helper functions */
static int ng_deflate_compress(node_p, struct mbuf *, struct mbuf **);
static int ng_deflate_decompress(node_p, struct mbuf *, struct mbuf **);
static void ng_deflate_reset_req(node_p);
/* Parse type for struct ng_deflate_config. */
static const struct ng_parse_struct_field ng_deflate_config_type_fields[]
= NG_DEFLATE_CONFIG_INFO;
static const struct ng_parse_type ng_deflate_config_type = {
&ng_parse_struct_type,
ng_deflate_config_type_fields
};
/* Parse type for struct ng_deflate_stat. */
static const struct ng_parse_struct_field ng_deflate_stats_type_fields[]
= NG_DEFLATE_STATS_INFO;
static const struct ng_parse_type ng_deflate_stat_type = {
&ng_parse_struct_type,
ng_deflate_stats_type_fields
};
/* List of commands and how to convert arguments to/from ASCII. */
static const struct ng_cmdlist ng_deflate_cmds[] = {
{
NGM_DEFLATE_COOKIE,
NGM_DEFLATE_CONFIG,
"config",
&ng_deflate_config_type,
NULL
},
{
NGM_DEFLATE_COOKIE,
NGM_DEFLATE_RESETREQ,
"resetreq",
NULL,
NULL
},
{
NGM_DEFLATE_COOKIE,
NGM_DEFLATE_GET_STATS,
"getstats",
NULL,
&ng_deflate_stat_type
},
{
NGM_DEFLATE_COOKIE,
NGM_DEFLATE_CLR_STATS,
"clrstats",
NULL,
NULL
},
{
NGM_DEFLATE_COOKIE,
NGM_DEFLATE_GETCLR_STATS,
"getclrstats",
NULL,
&ng_deflate_stat_type
},
{ 0 }
};
/* Node type descriptor */
static struct ng_type ng_deflate_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_DEFLATE_NODE_TYPE,
.constructor = ng_deflate_constructor,
.rcvmsg = ng_deflate_rcvmsg,
.shutdown = ng_deflate_shutdown,
.newhook = ng_deflate_newhook,
.rcvdata = ng_deflate_rcvdata,
.disconnect = ng_deflate_disconnect,
.cmdlist = ng_deflate_cmds,
};
NETGRAPH_INIT(deflate, &ng_deflate_typestruct);
/* Depend on separate zlib module. */
MODULE_DEPEND(ng_deflate, zlib, 1, 1, 1);
#define ERROUT(x) do { error = (x); goto done; } while (0)
/************************************************************************
NETGRAPH NODE STUFF
************************************************************************/
/*
* Node type constructor
*/
static int
ng_deflate_constructor(node_p node)
{
priv_p priv;
/* Allocate private structure. */
priv = malloc(sizeof(*priv), M_NETGRAPH_DEFLATE, M_WAITOK | M_ZERO);
NG_NODE_SET_PRIVATE(node, priv);
/* This node is not thread safe. */
NG_NODE_FORCE_WRITER(node);
/* Done */
return (0);
}
/*
* Give our OK for a hook to be added.
*/
static int
ng_deflate_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
if (NG_NODE_NUMHOOKS(node) > 0)
return (EINVAL);
if (strcmp(name, NG_DEFLATE_HOOK_COMP) == 0)
priv->compress = 1;
else if (strcmp(name, NG_DEFLATE_HOOK_DECOMP) == 0)
priv->compress = 0;
else
return (EINVAL);
return (0);
}
/*
* Receive a control message
*/
static int
ng_deflate_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);
if (msg->header.typecookie != NGM_DEFLATE_COOKIE)
ERROUT(EINVAL);
switch (msg->header.cmd) {
case NGM_DEFLATE_CONFIG:
{
struct ng_deflate_config *const cfg
= (struct ng_deflate_config *)msg->data;
/* Check configuration. */
if (msg->header.arglen != sizeof(*cfg))
ERROUT(EINVAL);
if (cfg->enable) {
if (cfg->windowBits < 8 || cfg->windowBits > 15)
ERROUT(EINVAL);
} else
cfg->windowBits = 0;
/* Clear previous state. */
if (priv->cfg.enable) {
if (priv->compress)
deflateEnd(&priv->cx);
else
inflateEnd(&priv->cx);
priv->cfg.enable = 0;
}
/* Configuration is OK, reset to it. */
priv->cfg = *cfg;
if (priv->cfg.enable) {
priv->cx.next_in = NULL;
int res;
if (priv->compress) {
if ((res = deflateInit2(&priv->cx,
Z_DEFAULT_COMPRESSION, Z_DEFLATED,
-cfg->windowBits, 8,
Z_DEFAULT_STRATEGY)) != Z_OK) {
log(LOG_NOTICE,
"deflateInit2: error %d, %s\n",
res, priv->cx.msg);
priv->cfg.enable = 0;
ERROUT(ENOMEM);
}
} else {
if ((res = inflateInit2(&priv->cx,
-cfg->windowBits)) != Z_OK) {
log(LOG_NOTICE,
"inflateInit2: error %d, %s\n",
res, priv->cx.msg);
priv->cfg.enable = 0;
ERROUT(ENOMEM);
}
}
}
/* Initialize other state. */
priv->seqnum = 0;
/* Save return address so we can send reset-req's */
priv->ctrlnode = NGI_RETADDR(item);
break;
}
case NGM_DEFLATE_RESETREQ:
ng_deflate_reset_req(node);
break;
case NGM_DEFLATE_GET_STATS:
case NGM_DEFLATE_CLR_STATS:
case NGM_DEFLATE_GETCLR_STATS:
/* Create response if requested. */
if (msg->header.cmd != NGM_DEFLATE_CLR_STATS) {
NG_MKRESPONSE(resp, msg,
sizeof(struct ng_deflate_stats), M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
bcopy(&priv->stats, resp->data,
sizeof(struct ng_deflate_stats));
}
/* Clear stats if requested. */
if (msg->header.cmd != NGM_DEFLATE_GET_STATS)
bzero(&priv->stats,
sizeof(struct ng_deflate_stats));
break;
default:
error = EINVAL;
break;
}
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive incoming data on our hook.
*/
static int
ng_deflate_rcvdata(hook_p hook, item_p item)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
struct mbuf *m, *out;
int error;
if (!priv->cfg.enable) {
NG_FREE_ITEM(item);
return (ENXIO);
}
NGI_GET_M(item, m);
/* Compress */
if (priv->compress) {
if ((error = ng_deflate_compress(node, m, &out)) != 0) {
NG_FREE_ITEM(item);
log(LOG_NOTICE, "%s: error: %d\n", __func__, error);
return (error);
}
} else { /* Decompress */
if ((error = ng_deflate_decompress(node, m, &out)) != 0) {
NG_FREE_ITEM(item);
log(LOG_NOTICE, "%s: error: %d\n", __func__, error);
if (priv->ctrlnode != 0) {
struct ng_mesg *msg;
/* Need to send a reset-request. */
NG_MKMESSAGE(msg, NGM_DEFLATE_COOKIE,
NGM_DEFLATE_RESETREQ, 0, M_NOWAIT);
if (msg == NULL)
return (error);
NG_SEND_MSG_ID(error, node, msg,
priv->ctrlnode, 0);
}
return (error);
}
}
NG_FWD_NEW_DATA(error, item, hook, out);
return (error);
}
/*
* Destroy node.
*/
static int
ng_deflate_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
/* Take down netgraph node. */
if (priv->cfg.enable) {
if (priv->compress)
deflateEnd(&priv->cx);
else
inflateEnd(&priv->cx);
}
free(priv, M_NETGRAPH_DEFLATE);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node); /* let the node escape */
return (0);
}
/*
* Hook disconnection
*/
static int
ng_deflate_disconnect(hook_p hook)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
if (priv->cfg.enable) {
if (priv->compress)
deflateEnd(&priv->cx);
else
inflateEnd(&priv->cx);
priv->cfg.enable = 0;
}
/* Go away if no longer connected. */
if ((NG_NODE_NUMHOOKS(node) == 0) && NG_NODE_IS_VALID(node))
ng_rmnode_self(node);
return (0);
}
/************************************************************************
HELPER STUFF
************************************************************************/
/*
* Compress/encrypt a packet and put the result in a new mbuf at *resultp.
* The original mbuf is not free'd.
*/
static int
ng_deflate_compress(node_p node, struct mbuf *m, struct mbuf **resultp)
{
const priv_p priv = NG_NODE_PRIVATE(node);
int outlen, inlen;
int rtn;
/* Initialize. */
*resultp = NULL;
inlen = m->m_pkthdr.len;
priv->stats.FramesPlain++;
priv->stats.InOctets+=inlen;
if (inlen > DEFLATE_BUF_SIZE) {
priv->stats.Errors++;
NG_FREE_M(m);
return (ENOMEM);
}
/* We must own the mbuf chain exclusively to modify it. */
m = m_unshare(m, M_NOWAIT);
if (m == NULL) {
priv->stats.Errors++;
return (ENOMEM);
}
/* Work with contiguous regions of memory. */
m_copydata(m, 0, inlen, (caddr_t)priv->inbuf);
outlen = DEFLATE_BUF_SIZE;
/* Compress "inbuf" into "outbuf". */
/* Prepare to compress. */
if (priv->inbuf[0] != 0) {
priv->cx.next_in = priv->inbuf;
priv->cx.avail_in = inlen;
} else {
priv->cx.next_in = priv->inbuf + 1; /* compress protocol */
priv->cx.avail_in = inlen - 1;
}
priv->cx.next_out = priv->outbuf + 2 + DEFLATE_HDRLEN;
priv->cx.avail_out = outlen - 2 - DEFLATE_HDRLEN;
/* Compress. */
rtn = deflate(&priv->cx, Z_SYNC_FLUSH);
/* Check return value. */
if (rtn != Z_OK) {
priv->stats.Errors++;
log(LOG_NOTICE, "ng_deflate: compression error: %d (%s)\n",
rtn, priv->cx.msg);
NG_FREE_M(m);
return (EINVAL);
}
/* Calculate resulting size. */
outlen -= priv->cx.avail_out;
/*
* Z_SYNC_FLUSH completes the current deflate block and follows
* it with an empty stored block that is three bits plus filler
* bits to the next byte, followed by four bytes (00 00 ff ff).
* RFC 1979 Section 2.1, "Data" requires the four bytes be
* removed before transmission.
*/
outlen -= 4;
MPASS(outlen > 0);
MPASS(priv->outbuf[outlen + 0] == 0x00);
MPASS(priv->outbuf[outlen + 1] == 0x00);
MPASS(priv->outbuf[outlen + 2] == 0xff);
MPASS(priv->outbuf[outlen + 3] == 0xff);
/* If we can't compress this packet, send it as-is. */
if (outlen > inlen) {
/* Return original packet uncompressed. */
*resultp = m;
priv->stats.FramesUncomp++;
priv->stats.OutOctets+=inlen;
} else {
/* Install header. */
be16enc(priv->outbuf, PROT_COMPD);
be16enc(priv->outbuf + 2, priv->seqnum);
/* Return packet in an mbuf. */
m_copyback(m, 0, outlen, (caddr_t)priv->outbuf);
if (m->m_pkthdr.len < outlen) {
m_freem(m);
priv->stats.Errors++;
return (ENOMEM);
} else if (outlen < m->m_pkthdr.len)
m_adj(m, outlen - m->m_pkthdr.len);
*resultp = m;
priv->stats.FramesComp++;
priv->stats.OutOctets+=outlen;
}
/* Update sequence number. */
priv->seqnum++;
return (0);
}
/*
* Decompress/decrypt packet and put the result in a new mbuf at *resultp.
* The original mbuf is not free'd.
*/
static int
ng_deflate_decompress(node_p node, struct mbuf *m, struct mbuf **resultp)
{
const priv_p priv = NG_NODE_PRIVATE(node);
int outlen, inlen, datalen;
int rtn;
uint16_t proto;
int offset;
uint16_t rseqnum;
u_char headbuf[5];
static u_char EMPTY_BLOCK[4] = { 0x00, 0x00, 0xff, 0xff };
/* Initialize. */
*resultp = NULL;
inlen = m->m_pkthdr.len;
if (inlen > DEFLATE_BUF_SIZE) {
priv->stats.Errors++;
NG_FREE_M(m);
priv->seqnum = 0;
return (ENOMEM);
}
/* We must own the mbuf chain exclusively to modify it. */
m = m_unshare(m, M_NOWAIT);
if (m == NULL) {
priv->stats.Errors++;
return (ENOMEM);
}
/* Work with contiguous regions of memory. */
m_copydata(m, 0, inlen, (caddr_t)priv->inbuf);
/* Separate proto. */
if ((priv->inbuf[0] & 0x01) != 0) {
proto = priv->inbuf[0];
offset = 1;
} else {
proto = be16dec(priv->inbuf);
offset = 2;
}
priv->stats.InOctets += inlen;
/* Packet is compressed, so decompress. */
if (proto == PROT_COMPD) {
priv->stats.FramesComp++;
/* Check sequence number. */
rseqnum = be16dec(priv->inbuf + offset);
offset += 2;
if (rseqnum != priv->seqnum) {
priv->stats.Errors++;
log(LOG_NOTICE, "ng_deflate: wrong sequence: %u "
"instead of %u\n", rseqnum, priv->seqnum);
NG_FREE_M(m);
priv->seqnum = 0;
return (EPIPE);
}
outlen = DEFLATE_BUF_SIZE;
/* Decompress "inbuf" into "outbuf". */
/* Prepare to decompress. */
priv->cx.next_in = priv->inbuf + offset;
priv->cx.avail_in = inlen - offset;
/* Reserve space for protocol decompression. */
priv->cx.next_out = priv->outbuf + 1;
priv->cx.avail_out = outlen - 1;
/* Decompress. */
rtn = inflate(&priv->cx, Z_SYNC_FLUSH);
/* Check return value. */
if (rtn != Z_OK && rtn != Z_STREAM_END) {
priv->stats.Errors++;
NG_FREE_M(m);
priv->seqnum = 0;
log(LOG_NOTICE, "%s: decompression error: %d (%s)\n",
__func__, rtn, priv->cx.msg);
switch (rtn) {
case Z_MEM_ERROR:
return (ENOMEM);
case Z_DATA_ERROR:
return (EIO);
default:
return (EINVAL);
}
}
/* Handle the EMPTY_BLOCK omitted by sender */
if (inflateSyncPoint(&priv->cx)) {
priv->cx.avail_in = 4;
priv->cx.next_in = EMPTY_BLOCK;
inflate(&priv->cx, Z_SYNC_FLUSH);
}
/* Calculate resulting size. */
outlen -= priv->cx.avail_out;
/* Decompress protocol. */
if ((priv->outbuf[1] & 0x01) != 0) {
priv->outbuf[0] = 0;
/* Return packet in an mbuf. */
m_copyback(m, 0, outlen, (caddr_t)priv->outbuf);
} else {
outlen--;
/* Return packet in an mbuf. */
m_copyback(m, 0, outlen, (caddr_t)(priv->outbuf + 1));
}
if (m->m_pkthdr.len < outlen) {
m_freem(m);
priv->stats.Errors++;
priv->seqnum = 0;
return (ENOMEM);
} else if (outlen < m->m_pkthdr.len)
m_adj(m, outlen - m->m_pkthdr.len);
*resultp = m;
priv->stats.FramesPlain++;
priv->stats.OutOctets+=outlen;
} else {
/* Packet is not compressed, just update dictionary. */
priv->stats.FramesUncomp++;
/*
* Fake a header for uncompressed data block
*/
datalen = inlen - offset + 1;
headbuf[0] = 0x80;
headbuf[1] = datalen & 0xff;
headbuf[2] = datalen >> 8;
headbuf[3] = (~datalen) & 0xff;
headbuf[4] = (~datalen) >> 8;
priv->cx.next_in = headbuf;
priv->cx.avail_in = sizeof(headbuf);
priv->cx.next_out = priv->outbuf;
priv->cx.avail_out = DEFLATE_BUF_SIZE;
rtn = inflate(&priv->cx, Z_NO_FLUSH);
if (priv->inbuf[0] == 0) {
priv->cx.next_in =
priv->inbuf + 1; /* compress protocol */
priv->cx.avail_in = inlen - 1;
} else {
priv->cx.next_in = priv->inbuf;
priv->cx.avail_in = inlen;
}
priv->cx.next_out = priv->outbuf;
priv->cx.avail_out = DEFLATE_BUF_SIZE;
rtn = inflate(&priv->cx, Z_SYNC_FLUSH);
/* Check return value */
if (rtn != Z_OK) {
priv->stats.Errors++;
log(LOG_NOTICE, "%s: inflate error: %d (%s)\n",
__func__, rtn, priv->cx.msg);
NG_FREE_M(m);
priv->seqnum = 0;
return (EINVAL);
}
*resultp = m;
priv->stats.FramesPlain++;
priv->stats.OutOctets += inlen;
}
/* Update sequence number. */
priv->seqnum++;
return (0);
}
/*
* The peer has sent us a CCP ResetRequest, so reset our transmit state.
*/
static void
ng_deflate_reset_req(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
priv->seqnum = 0;
if (priv->cfg.enable) {
if (priv->compress)
deflateReset(&priv->cx);
else
inflateReset(&priv->cx);
}
}
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