freebsd-dev/sys/netgraph/ng_patch.c
Julian Elischer 426b3d047a Changes to allow the patching of packets with an offset (and other changes.. see man page)
PR:	206185
Submitted by:	Dmitry Vagin <daemon-hammer@ya.ru>
MFC after:	 1 week
Relnotes:	yes (also ng_checksum node)
2016-12-02 10:47:10 +00:00

696 lines
16 KiB
C

/*-
* Copyright (c) 2010 Maxim Ignatenko <gelraen.ua@gmail.com>
* Copyright (c) 2015 Dmitry Vagin <daemon.hammer@ya.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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/endian.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <netgraph/ng_message.h>
#include <netgraph/ng_parse.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_patch.h>
/* private data */
struct ng_patch_priv {
hook_p in;
hook_p out;
uint8_t dlt; /* DLT_XXX from bpf.h */
struct ng_patch_stats stats;
struct ng_patch_config *conf;
};
typedef struct ng_patch_priv *priv_p;
/* Netgraph methods */
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 ERROUT(x) { error = (x); goto done; }
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 *conf;
conf = (const struct ng_patch_config *)(buf -
offsetof(struct ng_patch_config, ops));
return (conf->count);
}
static const struct ng_parse_struct_field ng_patch_op_type_fields[]
= NG_PATCH_OP_TYPE;
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_ops_array_info = {
&ng_patch_op_type,
&ng_patch_config_getlen
};
static const struct ng_parse_type ng_patch_ops_array_type = {
&ng_parse_array_type,
&ng_patch_ops_array_info
};
static const struct ng_parse_struct_field ng_patch_config_type_fields[]
= NG_PATCH_CONFIG_TYPE;
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;
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_GETDLT,
"getdlt",
NULL,
&ng_parse_uint8_type
},
{
NGM_PATCH_COOKIE,
NGM_PATCH_SETDLT,
"setdlt",
&ng_parse_uint8_type,
NULL
},
{
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);
static int
ng_patch_constructor(node_p node)
{
priv_p privdata;
privdata = malloc(sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO);
privdata->dlt = DLT_RAW;
NG_NODE_SET_PRIVATE(node, privdata);
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, *newconf;
struct ng_mesg *msg;
struct ng_mesg *resp = NULL;
int i, error = 0;
NGI_GET_MSG(item, msg);
if (msg->header.typecookie != NGM_PATCH_COOKIE)
ERROUT(EINVAL);
switch (msg->header.cmd)
{
case NGM_PATCH_GETCONFIG:
if (privp->conf == NULL)
ERROUT(0);
NG_MKRESPONSE(resp, msg,
NG_PATCH_CONF_SIZE(privp->conf->count), M_WAITOK);
if (resp == NULL)
ERROUT(ENOMEM);
bcopy(privp->conf, resp->data,
NG_PATCH_CONF_SIZE(privp->conf->count));
conf = (struct ng_patch_config *) resp->data;
for (i = 0; i < conf->count; i++) {
switch (conf->ops[i].length)
{
case 1:
conf->ops[i].val.v8 = conf->ops[i].val.v1;
break;
case 2:
conf->ops[i].val.v8 = conf->ops[i].val.v2;
break;
case 4:
conf->ops[i].val.v8 = conf->ops[i].val.v4;
break;
case 8:
break;
}
}
break;
case NGM_PATCH_SETCONFIG:
conf = (struct ng_patch_config *) msg->data;
if (msg->header.arglen < sizeof(struct ng_patch_config) ||
msg->header.arglen < NG_PATCH_CONF_SIZE(conf->count))
ERROUT(EINVAL);
for (i = 0; i < conf->count; i++) {
switch (conf->ops[i].length)
{
case 1:
conf->ops[i].val.v1 = (uint8_t) conf->ops[i].val.v8;
break;
case 2:
conf->ops[i].val.v2 = (uint16_t) conf->ops[i].val.v8;
break;
case 4:
conf->ops[i].val.v4 = (uint32_t) conf->ops[i].val.v8;
break;
case 8:
break;
default:
ERROUT(EINVAL);
}
}
conf->csum_flags &= NG_PATCH_CSUM_IPV4|NG_PATCH_CSUM_IPV6;
conf->relative_offset = !!conf->relative_offset;
newconf = malloc(NG_PATCH_CONF_SIZE(conf->count), M_NETGRAPH, M_WAITOK | M_ZERO);
bcopy(conf, newconf, NG_PATCH_CONF_SIZE(conf->count));
if (privp->conf)
free(privp->conf, M_NETGRAPH);
privp->conf = newconf;
break;
case NGM_PATCH_GET_STATS:
case NGM_PATCH_CLR_STATS:
case NGM_PATCH_GETCLR_STATS:
if (msg->header.cmd != NGM_PATCH_CLR_STATS) {
NG_MKRESPONSE(resp, msg, sizeof(struct ng_patch_stats), M_WAITOK);
if (resp == NULL)
ERROUT(ENOMEM);
bcopy(&(privp->stats), resp->data, sizeof(struct ng_patch_stats));
}
if (msg->header.cmd != NGM_PATCH_GET_STATS)
bzero(&(privp->stats), sizeof(struct ng_patch_stats));
break;
case NGM_PATCH_GETDLT:
NG_MKRESPONSE(resp, msg, sizeof(uint8_t), M_WAITOK);
if (resp == NULL)
ERROUT(ENOMEM);
*((uint8_t *) resp->data) = privp->dlt;
break;
case NGM_PATCH_SETDLT:
if (msg->header.arglen != sizeof(uint8_t))
ERROUT(EINVAL);
switch (*(uint8_t *) msg->data)
{
case DLT_EN10MB:
case DLT_RAW:
privp->dlt = *(uint8_t *) msg->data;
break;
default:
ERROUT(EINVAL);
}
break;
default:
ERROUT(EINVAL);
}
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
static void
do_patch(priv_p privp, struct mbuf *m, int global_offset)
{
int i, offset, patched = 0;
union ng_patch_op_val val;
for (i = 0; i < privp->conf->count; i++) {
offset = global_offset + privp->conf->ops[i].offset;
if (offset + privp->conf->ops[i].length > m->m_pkthdr.len)
continue;
/* for "=" operation we don't need to copy data from mbuf */
if (privp->conf->ops[i].mode != NG_PATCH_MODE_SET)
m_copydata(m, offset, privp->conf->ops[i].length, (caddr_t) &val);
switch (privp->conf->ops[i].length)
{
case 1:
switch (privp->conf->ops[i].mode)
{
case NG_PATCH_MODE_SET:
val.v1 = privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_ADD:
val.v1 += privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_SUB:
val.v1 -= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_MUL:
val.v1 *= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_DIV:
val.v1 /= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_NEG:
*((int8_t *) &val) = - *((int8_t *) &val);
break;
case NG_PATCH_MODE_AND:
val.v1 &= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_OR:
val.v1 |= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_XOR:
val.v1 ^= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_SHL:
val.v1 <<= privp->conf->ops[i].val.v1;
break;
case NG_PATCH_MODE_SHR:
val.v1 >>= privp->conf->ops[i].val.v1;
break;
}
break;
case 2:
val.v2 = ntohs(val.v2);
switch (privp->conf->ops[i].mode)
{
case NG_PATCH_MODE_SET:
val.v2 = privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_ADD:
val.v2 += privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_SUB:
val.v2 -= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_MUL:
val.v2 *= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_DIV:
val.v2 /= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_NEG:
*((int16_t *) &val) = - *((int16_t *) &val);
break;
case NG_PATCH_MODE_AND:
val.v2 &= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_OR:
val.v2 |= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_XOR:
val.v2 ^= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_SHL:
val.v2 <<= privp->conf->ops[i].val.v2;
break;
case NG_PATCH_MODE_SHR:
val.v2 >>= privp->conf->ops[i].val.v2;
break;
}
val.v2 = htons(val.v2);
break;
case 4:
val.v4 = ntohl(val.v4);
switch (privp->conf->ops[i].mode)
{
case NG_PATCH_MODE_SET:
val.v4 = privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_ADD:
val.v4 += privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_SUB:
val.v4 -= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_MUL:
val.v4 *= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_DIV:
val.v4 /= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_NEG:
*((int32_t *) &val) = - *((int32_t *) &val);
break;
case NG_PATCH_MODE_AND:
val.v4 &= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_OR:
val.v4 |= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_XOR:
val.v4 ^= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_SHL:
val.v4 <<= privp->conf->ops[i].val.v4;
break;
case NG_PATCH_MODE_SHR:
val.v4 >>= privp->conf->ops[i].val.v4;
break;
}
val.v4 = htonl(val.v4);
break;
case 8:
val.v8 = be64toh(val.v8);
switch (privp->conf->ops[i].mode)
{
case NG_PATCH_MODE_SET:
val.v8 = privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_ADD:
val.v8 += privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_SUB:
val.v8 -= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_MUL:
val.v8 *= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_DIV:
val.v8 /= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_NEG:
*((int64_t *) &val) = - *((int64_t *) &val);
break;
case NG_PATCH_MODE_AND:
val.v8 &= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_OR:
val.v8 |= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_XOR:
val.v8 ^= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_SHL:
val.v8 <<= privp->conf->ops[i].val.v8;
break;
case NG_PATCH_MODE_SHR:
val.v8 >>= privp->conf->ops[i].val.v8;
break;
}
val.v8 = htobe64(val.v8);
break;
}
m_copyback(m, offset, privp->conf->ops[i].length, (caddr_t) &val);
patched = 1;
}
if (patched)
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 out;
int pullup_len = 0;
int error = 0;
priv->stats.received++;
NGI_GET_M(item, m);
#define PULLUP_CHECK(mbuf, length) do { \
pullup_len += length; \
if (((mbuf)->m_pkthdr.len < pullup_len) || \
(pullup_len > MHLEN)) { \
error = EINVAL; \
goto bypass; \
} \
if ((mbuf)->m_len < pullup_len && \
(((mbuf) = m_pullup((mbuf), pullup_len)) == NULL)) { \
error = ENOBUFS; \
goto drop; \
} \
} while (0)
if (priv->conf && hook == priv->in &&
m && (m->m_flags & M_PKTHDR)) {
m = m_unshare(m, M_NOWAIT);
if (m == NULL)
ERROUT(ENOMEM);
if (priv->conf->relative_offset) {
struct ether_header *eh;
struct ng_patch_vlan_header *vh;
uint16_t etype;
switch (priv->dlt)
{
case DLT_EN10MB:
PULLUP_CHECK(m, sizeof(struct ether_header));
eh = mtod(m, struct ether_header *);
etype = ntohs(eh->ether_type);
for (;;) { /* QinQ support */
switch (etype)
{
case 0x8100:
case 0x88A8:
case 0x9100:
PULLUP_CHECK(m, sizeof(struct ng_patch_vlan_header));
vh = (struct ng_patch_vlan_header *) mtodo(m,
pullup_len - sizeof(struct ng_patch_vlan_header));
etype = ntohs(vh->etype);
break;
default:
goto loopend;
}
}
loopend:
break;
case DLT_RAW:
break;
default:
ERROUT(EINVAL);
}
}
do_patch(priv, m, pullup_len);
m->m_pkthdr.csum_flags |= priv->conf->csum_flags;
}
#undef PULLUP_CHECK
bypass:
out = NULL;
if (hook == priv->in) {
/* return frames on 'in' hook if 'out' not connected */
out = priv->out ? priv->out : priv->in;
} else if (hook == priv->out && priv->in) {
/* pass frames on 'out' hook if 'in' connected */
out = priv->in;
}
if (out == NULL)
ERROUT(0);
NG_FWD_NEW_DATA(error, item, out, m);
return (error);
done:
drop:
NG_FREE_ITEM(item);
NG_FREE_M(m);
priv->stats.dropped++;
return (error);
}
static int
ng_patch_shutdown(node_p node)
{
const priv_p privdata = NG_NODE_PRIVATE(node);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node);
if (privdata->conf != NULL)
free(privdata->conf, M_NETGRAPH);
free(privdata, M_NETGRAPH);
return (0);
}
static int
ng_patch_disconnect(hook_p hook)
{
priv_p priv;
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);
}