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/*
* DECnet An implementation of the DECnet protocol suite for the LINUX
* operating system. DECnet is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* DECnet Routing Forwarding Information Base (Rules)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
* Mostly copied from Alexey Kuznetsov's ipv4/fib_rules.c
*
*
* Changes:
* Steve Whitehouse <steve@chygwyn.com>
* Updated for Thomas Graf's generic rules
*
*/
#include <linux/net.h>
#include <linux/init.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/rcupdate.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/dn.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>
static struct fib_rules_ops dn_fib_rules_ops;
struct dn_fib_rule
{
struct fib_rule common;
unsigned char dst_len;
unsigned char src_len;
__le16 src;
__le16 srcmask;
__le16 dst;
__le16 dstmask;
__le16 srcmap;
u8 flags;
u32 fwmark;
u32 fwmask;
};
static struct dn_fib_rule default_rule = {
.common = {
.refcnt = ATOMIC_INIT(2),
.pref = 0x7fff,
.table = RT_TABLE_MAIN,
.action = FR_ACT_TO_TBL,
},
};
static LIST_HEAD(dn_fib_rules);
int dn_fib_lookup(struct flowi *flp, struct dn_fib_res *res)
{
struct fib_lookup_arg arg = {
.result = res,
};
int err;
err = fib_rules_lookup(&dn_fib_rules_ops, flp, 0, &arg);
res->r = arg.rule;
return err;
}
static int dn_fib_rule_action(struct fib_rule *rule, struct flowi *flp,
int flags, struct fib_lookup_arg *arg)
{
int err = -EAGAIN;
struct dn_fib_table *tbl;
switch(rule->action) {
case FR_ACT_TO_TBL:
break;
case FR_ACT_UNREACHABLE:
err = -ENETUNREACH;
goto errout;
case FR_ACT_PROHIBIT:
err = -EACCES;
goto errout;
case FR_ACT_BLACKHOLE:
default:
err = -EINVAL;
goto errout;
}
tbl = dn_fib_get_table(rule->table, 0);
if (tbl == NULL)
goto errout;
err = tbl->lookup(tbl, flp, (struct dn_fib_res *)arg->result);
if (err > 0)
err = -EAGAIN;
errout:
return err;
}
static struct nla_policy dn_fib_rule_policy[FRA_MAX+1] __read_mostly = {
[FRA_IFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
[FRA_PRIORITY] = { .type = NLA_U32 },
[FRA_SRC] = { .type = NLA_U16 },
[FRA_DST] = { .type = NLA_U16 },
[FRA_FWMARK] = { .type = NLA_U32 },
[FRA_FWMASK] = { .type = NLA_U32 },
[FRA_TABLE] = { .type = NLA_U32 },
};
static int dn_fib_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
__le16 daddr = fl->fld_dst;
__le16 saddr = fl->fld_src;
if (((saddr ^ r->src) & r->srcmask) ||
((daddr ^ r->dst) & r->dstmask))
return 0;
if ((r->fwmark ^ fl->mark) & r->fwmask)
return 0;
return 1;
}
static int dn_fib_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
struct nlattr **tb)
{
int err = -EINVAL;
struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
if (frh->src_len > 16 || frh->dst_len > 16 || frh->tos)
goto errout;
if (rule->table == RT_TABLE_UNSPEC) {
if (rule->action == FR_ACT_TO_TBL) {
struct dn_fib_table *table;
table = dn_fib_empty_table();
if (table == NULL) {
err = -ENOBUFS;
goto errout;
}
rule->table = table->n;
}
}
if (tb[FRA_SRC])
r->src = nla_get_u16(tb[FRA_SRC]);
if (tb[FRA_DST])
r->dst = nla_get_u16(tb[FRA_DST]);
if (tb[FRA_FWMARK]) {
r->fwmark = nla_get_u32(tb[FRA_FWMARK]);
if (r->fwmark)
/* compatibility: if the mark value is non-zero all bits
* are compared unless a mask is explicitly specified.
*/
r->fwmask = 0xFFFFFFFF;
}
if (tb[FRA_FWMASK])
r->fwmask = nla_get_u32(tb[FRA_FWMASK]);
r->src_len = frh->src_len;
r->srcmask = dnet_make_mask(r->src_len);
r->dst_len = frh->dst_len;
r->dstmask = dnet_make_mask(r->dst_len);
err = 0;
errout:
return err;
}
static int dn_fib_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
struct nlattr **tb)
{
struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
if (frh->src_len && (r->src_len != frh->src_len))
return 0;
if (frh->dst_len && (r->dst_len != frh->dst_len))
return 0;
if (tb[FRA_FWMARK] && (r->fwmark != nla_get_u32(tb[FRA_FWMARK])))
return 0;
if (tb[FRA_FWMASK] && (r->fwmask != nla_get_u32(tb[FRA_FWMASK])))
return 0;
if (tb[FRA_SRC] && (r->src != nla_get_u16(tb[FRA_SRC])))
return 0;
if (tb[FRA_DST] && (r->dst != nla_get_u16(tb[FRA_DST])))
return 0;
return 1;
}
unsigned dnet_addr_type(__le16 addr)
{
struct flowi fl = { .nl_u = { .dn_u = { .daddr = addr } } };
struct dn_fib_res res;
unsigned ret = RTN_UNICAST;
struct dn_fib_table *tb = dn_fib_get_table(RT_TABLE_LOCAL, 0);
res.r = NULL;
if (tb) {
if (!tb->lookup(tb, &fl, &res)) {
ret = res.type;
dn_fib_res_put(&res);
}
}
return ret;
}
static int dn_fib_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
{
struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
frh->family = AF_DECnet;
frh->dst_len = r->dst_len;
frh->src_len = r->src_len;
frh->tos = 0;
if (r->fwmark)
NLA_PUT_U32(skb, FRA_FWMARK, r->fwmark);
if (r->fwmask || r->fwmark)
NLA_PUT_U32(skb, FRA_FWMASK, r->fwmask);
if (r->dst_len)
NLA_PUT_U16(skb, FRA_DST, r->dst);
if (r->src_len)
NLA_PUT_U16(skb, FRA_SRC, r->src);
return 0;
nla_put_failure:
return -ENOBUFS;
}
static u32 dn_fib_rule_default_pref(void)
{
struct list_head *pos;
struct fib_rule *rule;
if (!list_empty(&dn_fib_rules)) {
pos = dn_fib_rules.next;
if (pos->next != &dn_fib_rules) {
rule = list_entry(pos->next, struct fib_rule, list);
if (rule->pref)
return rule->pref - 1;
}
}
return 0;
}
int dn_fib_dump_rules(struct sk_buff *skb, struct netlink_callback *cb)
{
return fib_rules_dump(skb, cb, AF_DECnet);
}
static struct fib_rules_ops dn_fib_rules_ops = {
.family = AF_DECnet,
.rule_size = sizeof(struct dn_fib_rule),
.action = dn_fib_rule_action,
.match = dn_fib_rule_match,
.configure = dn_fib_rule_configure,
.compare = dn_fib_rule_compare,
.fill = dn_fib_rule_fill,
.default_pref = dn_fib_rule_default_pref,
.nlgroup = RTNLGRP_DECnet_RULE,
.policy = dn_fib_rule_policy,
.rules_list = &dn_fib_rules,
.owner = THIS_MODULE,
};
void __init dn_fib_rules_init(void)
{
list_add_tail(&default_rule.common.list, &dn_fib_rules);
fib_rules_register(&dn_fib_rules_ops);
}
void __exit dn_fib_rules_cleanup(void)
{
fib_rules_unregister(&dn_fib_rules_ops);
}
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