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/**
* @file net_ipv4_route.c
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* 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.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 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.
*
* @section DESCRIPTION
*
* IPv4 route module.
*
* Synopsis:
* net.ipv4.route(string dest, string dest_prefix, string gateway, string metric, string ifname)
* net.ipv4.route(string cidr_dest, string gateway, string metric, string ifname)
*
* Description:
* Adds an IPv4 route to the system's routing table on initiailzation, and
* removes it on deinitialization. The second form takes the destination in
* CIDR notation (a.b.c.d/n).
* If 'gateway' is "none", the route will only be associated with an interface.
* If 'gateway' is "blackhole", the route will be a blackhole route (and 'ifname' is unused).
*/
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <misc/debug.h>
#include <ncd/extra/NCDIfConfig.h>
#include <ncd/module_common.h>
#include <generated/blog_channel_ncd_net_ipv4_route.h>
#define TYPE_NORMAL 1
#define TYPE_IFONLY 2
#define TYPE_BLACKHOLE 3
struct instance {
NCDModuleInst *i;
struct ipv4_ifaddr dest;
int type;
uint32_t gateway;
int metric;
NCDValNullTermString ifname_nts;
};
static void func_new (void *vo, NCDModuleInst *i, const struct NCDModuleInst_new_params *params)
{
struct instance *o = vo;
o->i = i;
// read arguments
NCDValRef dest_arg;
NCDValRef dest_prefix_arg = NCDVal_NewInvalid();
NCDValRef gateway_arg;
NCDValRef metric_arg;
NCDValRef ifname_arg;
if (!NCDVal_ListRead(params->args, 4, &dest_arg, &gateway_arg, &metric_arg, &ifname_arg) &&
!NCDVal_ListRead(params->args, 5, &dest_arg, &dest_prefix_arg, &gateway_arg, &metric_arg, &ifname_arg)
) {
ModuleLog(o->i, BLOG_ERROR, "wrong arity");
goto fail0;
}
if (!NCDVal_IsString(dest_arg) || !NCDVal_IsString(gateway_arg) ||
!NCDVal_IsStringNoNulls(ifname_arg) ||
(!NCDVal_IsInvalid(dest_prefix_arg) && !NCDVal_IsString(dest_prefix_arg))
) {
ModuleLog(o->i, BLOG_ERROR, "wrong type");
goto fail0;
}
// read dest
if (NCDVal_IsInvalid(dest_prefix_arg)) {
if (!ipaddr_parse_ipv4_ifaddr(NCDVal_StringMemRef(dest_arg), &o->dest)) {
ModuleLog(o->i, BLOG_ERROR, "wrong CIDR notation dest");
goto fail0;
}
} else {
if (!ipaddr_parse_ipv4_addr(NCDVal_StringMemRef(dest_arg), &o->dest.addr)) {
ModuleLog(o->i, BLOG_ERROR, "wrong dest addr");
goto fail0;
}
if (!ipaddr_parse_ipv4_prefix(NCDVal_StringMemRef(dest_prefix_arg), &o->dest.prefix)) {
ModuleLog(o->i, BLOG_ERROR, "wrong dest prefix");
goto fail0;
}
}
// read gateway and choose type
if (NCDVal_StringEquals(gateway_arg, "none")) {
o->type = TYPE_IFONLY;
}
else if (NCDVal_StringEquals(gateway_arg, "blackhole")) {
o->type = TYPE_BLACKHOLE;
} else {
if (!ipaddr_parse_ipv4_addr(NCDVal_StringMemRef(gateway_arg), &o->gateway)) {
ModuleLog(o->i, BLOG_ERROR, "wrong gateway");
goto fail0;
}
o->type = TYPE_NORMAL;
}
// read metric
uintmax_t metric;
if (!ncd_read_uintmax(metric_arg, &metric) || metric > INT_MAX) {
ModuleLog(i, BLOG_ERROR, "bad metric");
goto fail0;
}
o->metric = metric;
// null terminate ifname
if (!NCDVal_StringNullTerminate(ifname_arg, &o->ifname_nts)) {
ModuleLog(i, BLOG_ERROR, "NCDVal_StringNullTerminate failed");
goto fail0;
}
// add route
int res = 0; // to remove warning
switch (o->type) {
case TYPE_NORMAL:
res = NCDIfConfig_add_ipv4_route(o->dest, &o->gateway, o->metric, o->ifname_nts.data);
break;
case TYPE_IFONLY:
res = NCDIfConfig_add_ipv4_route(o->dest, NULL, o->metric, o->ifname_nts.data);
break;
case TYPE_BLACKHOLE:
res = NCDIfConfig_add_ipv4_blackhole_route(o->dest, o->metric);
break;
default: ASSERT(0);
}
if (!res) {
ModuleLog(o->i, BLOG_ERROR, "failed to add route");
goto fail1;
}
// signal up
NCDModuleInst_Backend_Up(o->i);
return;
fail1:
NCDValNullTermString_Free(&o->ifname_nts);
fail0:
NCDModuleInst_Backend_DeadError(i);
}
static void func_die (void *vo)
{
struct instance *o = vo;
// remove route
int res = 0; // to remove warning
switch (o->type) {
case TYPE_NORMAL:
res = NCDIfConfig_remove_ipv4_route(o->dest, &o->gateway, o->metric, o->ifname_nts.data);
break;
case TYPE_IFONLY:
res = NCDIfConfig_remove_ipv4_route(o->dest, NULL, o->metric, o->ifname_nts.data);
break;
case TYPE_BLACKHOLE:
res = NCDIfConfig_remove_ipv4_blackhole_route(o->dest, o->metric);
break;
default: ASSERT(0);
}
if (!res) {
ModuleLog(o->i, BLOG_ERROR, "failed to remove route");
}
// free ifname nts
NCDValNullTermString_Free(&o->ifname_nts);
NCDModuleInst_Backend_Dead(o->i);
}
static struct NCDModule modules[] = {
{
.type = "net.ipv4.route",
.func_new2 = func_new,
.func_die = func_die,
.alloc_size = sizeof(struct instance)
}, {
.type = NULL
}
};
const struct NCDModuleGroup ncdmodule_net_ipv4_route = {
.modules = modules
};