freebsd-skq/sys/netgraph/ng_vlan_rotate.c
Lutz Donnerhacke cfd6422a52 netgraph/ng_vlan_rotate: IEEE 802.1ad VLAN manipulation netgraph type
This node is part of an A10-NSP (L2-BSA) development.

Carrier networks tend to stack three or more tags for internal
purposes and therefore hiding the service tags deep inside of the
stack. When decomposing such an access network frame, the processing
order is typically reversed: First distinguish by service, than by
other means.

This new netgragh node allows to bring the relevant VLAN in front (to
the out-most position). This way other netgraph nodes (like ng_vlan)
can operate on this specific type.

Reviewed by:	manpages (gbe), brueffer (manpages), kp
Approved by:	kp (mentor)
MFC after:	1 month
Relnotes:	yes
Sponsored by:	IKS Service GmbH
Differential Revision: https://reviews.freebsd.org/D22076
2021-01-26 16:53:24 +01:00

511 lines
12 KiB
C

/*-
* Spdx-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019-2021 IKS Service GmbH
*
* 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.
*
* Author: Lutz Donnerhacke <lutz@donnerhacke.de>
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/ctype.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <sys/types.h>
#include <sys/counter.h>
#include <net/ethernet.h>
#include <netgraph/ng_message.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_vlan_rotate.h>
#include <netgraph/netgraph.h>
/*
* This section contains the netgraph method declarations for the
* sample node. These methods define the netgraph 'type'.
*/
static ng_constructor_t ng_vlanrotate_constructor;
static ng_rcvmsg_t ng_vlanrotate_rcvmsg;
static ng_shutdown_t ng_vlanrotate_shutdown;
static ng_newhook_t ng_vlanrotate_newhook;
static ng_rcvdata_t ng_vlanrotate_rcvdata;
static ng_disconnect_t ng_vlanrotate_disconnect;
/* Parse type for struct ng_vlanrotate_conf */
static const struct ng_parse_struct_field ng_vlanrotate_conf_fields[] = {
{"rot", &ng_parse_int8_type},
{"min", &ng_parse_uint8_type},
{"max", &ng_parse_uint8_type},
{NULL}
};
static const struct ng_parse_type ng_vlanrotate_conf_type = {
&ng_parse_struct_type,
&ng_vlanrotate_conf_fields
};
/* Parse type for struct ng_vlanrotate_stat */
static struct ng_parse_fixedarray_info ng_vlanrotate_stat_hist_info = {
&ng_parse_uint64_type,
NG_VLANROTATE_MAX_VLANS
};
static struct ng_parse_type ng_vlanrotate_stat_hist = {
&ng_parse_fixedarray_type,
&ng_vlanrotate_stat_hist_info
};
static const struct ng_parse_struct_field ng_vlanrotate_stat_fields[] = {
{"drops", &ng_parse_uint64_type},
{"excessive", &ng_parse_uint64_type},
{"incomplete", &ng_parse_uint64_type},
{"histogram", &ng_vlanrotate_stat_hist},
{NULL}
};
static struct ng_parse_type ng_vlanrotate_stat_type = {
&ng_parse_struct_type,
&ng_vlanrotate_stat_fields
};
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_vlanrotate_cmdlist[] = {
{
NGM_VLANROTATE_COOKIE,
NGM_VLANROTATE_GET_CONF,
"getconf",
NULL,
&ng_vlanrotate_conf_type,
},
{
NGM_VLANROTATE_COOKIE,
NGM_VLANROTATE_SET_CONF,
"setconf",
&ng_vlanrotate_conf_type,
NULL
},
{
NGM_VLANROTATE_COOKIE,
NGM_VLANROTATE_GET_STAT,
"getstat",
NULL,
&ng_vlanrotate_stat_type
},
{
NGM_VLANROTATE_COOKIE,
NGM_VLANROTATE_CLR_STAT,
"clrstat",
NULL,
&ng_vlanrotate_stat_type
},
{
NGM_VLANROTATE_COOKIE,
NGM_VLANROTATE_GETCLR_STAT,
"getclrstat",
NULL,
&ng_vlanrotate_stat_type
},
{0}
};
/* Netgraph node type descriptor */
static struct ng_type typestruct = {
.version = NG_ABI_VERSION,
.name = NG_VLANROTATE_NODE_TYPE,
.constructor = ng_vlanrotate_constructor,
.rcvmsg = ng_vlanrotate_rcvmsg,
.shutdown = ng_vlanrotate_shutdown,
.newhook = ng_vlanrotate_newhook,
.rcvdata = ng_vlanrotate_rcvdata,
.disconnect = ng_vlanrotate_disconnect,
.cmdlist = ng_vlanrotate_cmdlist,
};
NETGRAPH_INIT(vlanrotate, &typestruct);
struct ng_vlanrotate_kernel_stats {
counter_u64_t drops, excessive, incomplete;
counter_u64_t histogram[NG_VLANROTATE_MAX_VLANS];
};
/* Information we store for each node */
struct vlanrotate {
hook_p original_hook;
hook_p ordered_hook;
hook_p excessive_hook;
hook_p incomplete_hook;
struct ng_vlanrotate_conf conf;
struct ng_vlanrotate_kernel_stats stats;
};
typedef struct vlanrotate *vlanrotate_p;
/*
* Set up the private data structure.
*/
static int
ng_vlanrotate_constructor(node_p node)
{
int i;
vlanrotate_p vrp = malloc(sizeof(*vrp), M_NETGRAPH, M_WAITOK | M_ZERO);
vrp->conf.max = NG_VLANROTATE_MAX_VLANS;
vrp->stats.drops = counter_u64_alloc(M_WAITOK);
vrp->stats.excessive = counter_u64_alloc(M_WAITOK);
vrp->stats.incomplete = counter_u64_alloc(M_WAITOK);
for (i = 0; i < NG_VLANROTATE_MAX_VLANS; i++)
vrp->stats.histogram[i] = counter_u64_alloc(M_WAITOK);
NG_NODE_SET_PRIVATE(node, vrp);
return (0);
}
/*
* Give our ok for a hook to be added.
*/
static int
ng_vlanrotate_newhook(node_p node, hook_p hook, const char *name)
{
const vlanrotate_p vrp = NG_NODE_PRIVATE(node);
hook_p *dst = NULL;
if (strcmp(name, NG_VLANROTATE_HOOK_ORDERED) == 0) {
dst = &vrp->ordered_hook;
} else if (strcmp(name, NG_VLANROTATE_HOOK_ORIGINAL) == 0) {
dst = &vrp->original_hook;
} else if (strcmp(name, NG_VLANROTATE_HOOK_EXCESSIVE) == 0) {
dst = &vrp->excessive_hook;
} else if (strcmp(name, NG_VLANROTATE_HOOK_INCOMPLETE) == 0) {
dst = &vrp->incomplete_hook;
} else
return (EINVAL); /* not a hook we know about */
if (*dst != NULL)
return (EADDRINUSE); /* don't override */
*dst = hook;
return (0);
}
/*
* Get a netgraph control message.
* A response is not required.
*/
static int
ng_vlanrotate_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const vlanrotate_p vrp = NG_NODE_PRIVATE(node);
struct ng_mesg *resp = NULL;
struct ng_mesg *msg;
struct ng_vlanrotate_conf *pcf;
int error = 0;
NGI_GET_MSG(item, msg);
/* Deal with message according to cookie and command */
switch (msg->header.typecookie) {
case NGM_VLANROTATE_COOKIE:
switch (msg->header.cmd) {
case NGM_VLANROTATE_GET_CONF:
NG_MKRESPONSE(resp, msg, sizeof(vrp->conf), M_NOWAIT);
if (!resp) {
error = ENOMEM;
break;
}
*((struct ng_vlanrotate_conf *)resp->data) = vrp->conf;
break;
case NGM_VLANROTATE_SET_CONF:
if (msg->header.arglen != sizeof(*pcf)) {
error = EINVAL;
break;
}
pcf = (struct ng_vlanrotate_conf *)msg->data;
if (pcf->max == 0) /* keep current value */
pcf->max = vrp->conf.max;
if ((pcf->max > NG_VLANROTATE_MAX_VLANS) ||
(pcf->min > pcf->max) ||
(abs(pcf->rot) >= pcf->max)) {
error = EINVAL;
break;
}
vrp->conf = *pcf;
break;
case NGM_VLANROTATE_GET_STAT:
case NGM_VLANROTATE_GETCLR_STAT:
{
struct ng_vlanrotate_stat *p;
int i;
NG_MKRESPONSE(resp, msg, sizeof(*p), M_NOWAIT);
if (!resp) {
error = ENOMEM;
break;
}
p = (struct ng_vlanrotate_stat *)resp->data;
p->drops = counter_u64_fetch(vrp->stats.drops);
p->excessive = counter_u64_fetch(vrp->stats.excessive);
p->incomplete = counter_u64_fetch(vrp->stats.incomplete);
for (i = 0; i < NG_VLANROTATE_MAX_VLANS; i++)
p->histogram[i] = counter_u64_fetch(vrp->stats.histogram[i]);
if (msg->header.cmd != NGM_VLANROTATE_GETCLR_STAT)
break;
}
case NGM_VLANROTATE_CLR_STAT:
{
int i;
counter_u64_zero(vrp->stats.drops);
counter_u64_zero(vrp->stats.excessive);
counter_u64_zero(vrp->stats.incomplete);
for (i = 0; i < NG_VLANROTATE_MAX_VLANS; i++)
counter_u64_zero(vrp->stats.histogram[i]);
break;
}
default:
error = EINVAL; /* unknown command */
break;
}
break;
default:
error = EINVAL; /* unknown cookie type */
break;
}
/* Take care of synchronous response, if any */
NG_RESPOND_MSG(error, node, item, resp);
/* Free the message and return */
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive data, and do rotate the vlans as desired.
*
* Rotating is quite complicated if the rotation offset and the number
* of vlans are not relativly prime. In this case multiple slices need
* to be rotated separately.
*
* Rotation can be additive or subtractive. Some examples:
* 01234 5 vlans given
* -----
* 34012 +2 rotate
* 12340 +4 rotate
* 12340 -1 rotate
*
* First some helper functions ...
*/
struct ether_vlan_stack_entry {
uint16_t proto;
uint16_t tag;
} __packed;
struct ether_vlan_stack_header {
uint8_t dst[ETHER_ADDR_LEN];
uint8_t src[ETHER_ADDR_LEN];
struct ether_vlan_stack_entry vlan_stack[1];
} __packed;
static int
ng_vlanrotate_gcd(int a, int b)
{
if (b == 0)
return a;
else
return ng_vlanrotate_gcd(b, a % b);
}
static void
ng_vlanrotate_rotate(struct ether_vlan_stack_entry arr[], int d, int n)
{
int i, j, k;
struct ether_vlan_stack_entry temp;
/* for each commensurable slice */
for (i = ng_vlanrotate_gcd(d, n); i-- > 0;) {
/* rotate left aka downwards */
temp = arr[i];
j = i;
while (1) {
k = j + d;
if (k >= n)
k = k - n;
if (k == i)
break;
arr[j] = arr[k];
j = k;
}
arr[j] = temp;
}
}
static int
ng_vlanrotate_rcvdata(hook_p hook, item_p item)
{
const vlanrotate_p vrp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct ether_vlan_stack_header *evsh;
struct mbuf *m = NULL;
hook_p dst_hook;
int8_t rotate;
int8_t vlans = 0;
int error = ENOSYS;
NGI_GET_M(item, m);
if (hook == vrp->ordered_hook) {
rotate = +vrp->conf.rot;
dst_hook = vrp->original_hook;
} else if (hook == vrp->original_hook) {
rotate = -vrp->conf.rot;
dst_hook = vrp->ordered_hook;
} else {
dst_hook = vrp->original_hook;
goto send; /* everything else goes out unmodified */
}
if (dst_hook == NULL) {
error = ENETDOWN;
goto fail;
}
/* count the vlans */
for (vlans = 0; vlans <= NG_VLANROTATE_MAX_VLANS; vlans++) {
size_t expected_len = sizeof(struct ether_vlan_stack_header)
+ vlans * sizeof(struct ether_vlan_stack_entry);
if (m->m_len < expected_len) {
m = m_pullup(m, expected_len);
if (m == NULL) {
error = EINVAL;
goto fail;
}
}
evsh = mtod(m, struct ether_vlan_stack_header *);
switch (ntohs(evsh->vlan_stack[vlans].proto)) {
case ETHERTYPE_VLAN:
case ETHERTYPE_QINQ:
case ETHERTYPE_8021Q9100:
case ETHERTYPE_8021Q9200:
case ETHERTYPE_8021Q9300:
break;
default:
goto out;
}
}
out:
if ((vlans > vrp->conf.max) || (vlans >= NG_VLANROTATE_MAX_VLANS)) {
counter_u64_add(vrp->stats.excessive, 1);
dst_hook = vrp->excessive_hook;
goto send;
}
if ((vlans < vrp->conf.min) || (vlans <= abs(rotate))) {
counter_u64_add(vrp->stats.incomplete, 1);
dst_hook = vrp->incomplete_hook;
goto send;
}
counter_u64_add(vrp->stats.histogram[vlans], 1);
/* rotating upwards always (using modular arithmetics) */
if (rotate == 0) {
/* nothing to do */
} else if (rotate > 0) {
ng_vlanrotate_rotate(evsh->vlan_stack, rotate, vlans);
} else {
ng_vlanrotate_rotate(evsh->vlan_stack, vlans + rotate, vlans);
}
send:
if (dst_hook == NULL)
goto fail;
NG_FWD_NEW_DATA(error, item, dst_hook, m);
return 0;
fail:
counter_u64_add(vrp->stats.drops, 1);
if (m != NULL)
m_freem(m);
NG_FREE_ITEM(item);
return (error);
}
/*
* Do local shutdown processing..
* All our links and the name have already been removed.
*/
static int
ng_vlanrotate_shutdown(node_p node)
{
const vlanrotate_p vrp = NG_NODE_PRIVATE(node);
int i;
NG_NODE_SET_PRIVATE(node, NULL);
counter_u64_free(vrp->stats.drops);
counter_u64_free(vrp->stats.excessive);
counter_u64_free(vrp->stats.incomplete);
for (i = 0; i < NG_VLANROTATE_MAX_VLANS; i++)
counter_u64_free(vrp->stats.histogram[i]);
free(vrp, M_NETGRAPH);
NG_NODE_UNREF(node);
return (0);
}
/*
* Hook disconnection
* For this type, removal of the last link destroys the node
*/
static int
ng_vlanrotate_disconnect(hook_p hook)
{
const vlanrotate_p vrp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
if (vrp->original_hook == hook)
vrp->original_hook = NULL;
if (vrp->ordered_hook == hook)
vrp->ordered_hook = NULL;
if (vrp->excessive_hook == hook)
vrp->excessive_hook = NULL;
if (vrp->incomplete_hook == hook)
vrp->incomplete_hook = NULL;
/* during shutdown the node is invalid, don't shutdown twice */
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) &&
(NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
ng_rmnode_self(NG_HOOK_NODE(hook));
return (0);
}