kernel-ark/net/decnet/dn_rules.c
Jamal Hadi Salim b6544c0b4c [NETLINK]: Correctly set NLM_F_MULTI without checking the pid
This patch rectifies some rtnetlink message builders that derive the
flags from the pid. It is now explicit like the other cases
which get it right. Also fixes half a dozen dumpers which did not
set NLM_F_MULTI at all.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:54:12 -07:00

418 lines
9.8 KiB
C

/*
* 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:
*
*/
#include <linux/config.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/in_route.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/dn.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>
struct dn_fib_rule
{
struct dn_fib_rule *r_next;
atomic_t r_clntref;
u32 r_preference;
unsigned char r_table;
unsigned char r_action;
unsigned char r_dst_len;
unsigned char r_src_len;
dn_address r_src;
dn_address r_srcmask;
dn_address r_dst;
dn_address r_dstmask;
dn_address r_srcmap;
u8 r_flags;
#ifdef CONFIG_DECNET_ROUTE_FWMARK
u32 r_fwmark;
#endif
int r_ifindex;
char r_ifname[IFNAMSIZ];
int r_dead;
};
static struct dn_fib_rule default_rule = {
.r_clntref = ATOMIC_INIT(2),
.r_preference = 0x7fff,
.r_table = RT_TABLE_MAIN,
.r_action = RTN_UNICAST
};
static struct dn_fib_rule *dn_fib_rules = &default_rule;
static DEFINE_RWLOCK(dn_fib_rules_lock);
int dn_fib_rtm_delrule(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct rtmsg *rtm = NLMSG_DATA(nlh);
struct dn_fib_rule *r, **rp;
int err = -ESRCH;
for(rp=&dn_fib_rules; (r=*rp) != NULL; rp = &r->r_next) {
if ((!rta[RTA_SRC-1] || memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 2) == 0) &&
rtm->rtm_src_len == r->r_src_len &&
rtm->rtm_dst_len == r->r_dst_len &&
(!rta[RTA_DST-1] || memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 2) == 0) &&
#ifdef CONFIG_DECNET_ROUTE_FWMARK
(!rta[RTA_PROTOINFO-1] || memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
#endif
(!rtm->rtm_type || rtm->rtm_type == r->r_action) &&
(!rta[RTA_PRIORITY-1] || memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
(!rta[RTA_IIF-1] || rtattr_strcmp(rta[RTA_IIF-1], r->r_ifname) == 0) &&
(!rtm->rtm_table || (r && rtm->rtm_table == r->r_table))) {
err = -EPERM;
if (r == &default_rule)
break;
write_lock_bh(&dn_fib_rules_lock);
*rp = r->r_next;
r->r_dead = 1;
write_unlock_bh(&dn_fib_rules_lock);
dn_fib_rule_put(r);
err = 0;
break;
}
}
return err;
}
void dn_fib_rule_put(struct dn_fib_rule *r)
{
if (atomic_dec_and_test(&r->r_clntref)) {
if (r->r_dead)
kfree(r);
else
printk(KERN_DEBUG "Attempt to free alive dn_fib_rule\n");
}
}
int dn_fib_rtm_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct rtmsg *rtm = NLMSG_DATA(nlh);
struct dn_fib_rule *r, *new_r, **rp;
unsigned char table_id;
if (rtm->rtm_src_len > 16 || rtm->rtm_dst_len > 16)
return -EINVAL;
if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
return -EINVAL;
if (rtm->rtm_type == RTN_NAT)
return -EINVAL;
table_id = rtm->rtm_table;
if (table_id == RT_TABLE_UNSPEC) {
struct dn_fib_table *tb;
if (rtm->rtm_type == RTN_UNICAST) {
if ((tb = dn_fib_empty_table()) == NULL)
return -ENOBUFS;
table_id = tb->n;
}
}
new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
if (!new_r)
return -ENOMEM;
memset(new_r, 0, sizeof(*new_r));
if (rta[RTA_SRC-1])
memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 2);
if (rta[RTA_DST-1])
memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 2);
if (rta[RTA_GATEWAY-1])
memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 2);
new_r->r_src_len = rtm->rtm_src_len;
new_r->r_dst_len = rtm->rtm_dst_len;
new_r->r_srcmask = dnet_make_mask(rtm->rtm_src_len);
new_r->r_dstmask = dnet_make_mask(rtm->rtm_dst_len);
#ifdef CONFIG_DECNET_ROUTE_FWMARK
if (rta[RTA_PROTOINFO-1])
memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
#endif
new_r->r_action = rtm->rtm_type;
new_r->r_flags = rtm->rtm_flags;
if (rta[RTA_PRIORITY-1])
memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
new_r->r_table = table_id;
if (rta[RTA_IIF-1]) {
struct net_device *dev;
rtattr_strlcpy(new_r->r_ifname, rta[RTA_IIF-1], IFNAMSIZ);
new_r->r_ifindex = -1;
dev = dev_get_by_name(new_r->r_ifname);
if (dev) {
new_r->r_ifindex = dev->ifindex;
dev_put(dev);
}
}
rp = &dn_fib_rules;
if (!new_r->r_preference) {
r = dn_fib_rules;
if (r && (r = r->r_next) != NULL) {
rp = &dn_fib_rules->r_next;
if (r->r_preference)
new_r->r_preference = r->r_preference - 1;
}
}
while((r=*rp) != NULL) {
if (r->r_preference > new_r->r_preference)
break;
rp = &r->r_next;
}
new_r->r_next = r;
atomic_inc(&new_r->r_clntref);
write_lock_bh(&dn_fib_rules_lock);
*rp = new_r;
write_unlock_bh(&dn_fib_rules_lock);
return 0;
}
int dn_fib_lookup(const struct flowi *flp, struct dn_fib_res *res)
{
struct dn_fib_rule *r, *policy;
struct dn_fib_table *tb;
dn_address saddr = flp->fld_src;
dn_address daddr = flp->fld_dst;
int err;
read_lock(&dn_fib_rules_lock);
for(r = dn_fib_rules; r; r = r->r_next) {
if (((saddr^r->r_src) & r->r_srcmask) ||
((daddr^r->r_dst) & r->r_dstmask) ||
#ifdef CONFIG_DECNET_ROUTE_FWMARK
(r->r_fwmark && r->r_fwmark != flp->fld_fwmark) ||
#endif
(r->r_ifindex && r->r_ifindex != flp->iif))
continue;
switch(r->r_action) {
case RTN_UNICAST:
case RTN_NAT:
policy = r;
break;
case RTN_UNREACHABLE:
read_unlock(&dn_fib_rules_lock);
return -ENETUNREACH;
default:
case RTN_BLACKHOLE:
read_unlock(&dn_fib_rules_lock);
return -EINVAL;
case RTN_PROHIBIT:
read_unlock(&dn_fib_rules_lock);
return -EACCES;
}
if ((tb = dn_fib_get_table(r->r_table, 0)) == NULL)
continue;
err = tb->lookup(tb, flp, res);
if (err == 0) {
res->r = policy;
if (policy)
atomic_inc(&policy->r_clntref);
read_unlock(&dn_fib_rules_lock);
return 0;
}
if (err < 0 && err != -EAGAIN) {
read_unlock(&dn_fib_rules_lock);
return err;
}
}
read_unlock(&dn_fib_rules_lock);
return -ESRCH;
}
unsigned dnet_addr_type(__u16 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_tables[RT_TABLE_LOCAL];
res.r = NULL;
if (tb) {
if (!tb->lookup(tb, &fl, &res)) {
ret = res.type;
dn_fib_res_put(&res);
}
}
return ret;
}
__u16 dn_fib_rules_policy(__u16 saddr, struct dn_fib_res *res, unsigned *flags)
{
struct dn_fib_rule *r = res->r;
if (r->r_action == RTN_NAT) {
int addrtype = dnet_addr_type(r->r_srcmap);
if (addrtype == RTN_NAT) {
saddr = (saddr&~r->r_srcmask)|r->r_srcmap;
*flags |= RTCF_SNAT;
} else if (addrtype == RTN_LOCAL || r->r_srcmap == 0) {
saddr = r->r_srcmap;
*flags |= RTCF_MASQ;
}
}
return saddr;
}
static void dn_fib_rules_detach(struct net_device *dev)
{
struct dn_fib_rule *r;
for(r = dn_fib_rules; r; r = r->r_next) {
if (r->r_ifindex == dev->ifindex) {
write_lock_bh(&dn_fib_rules_lock);
r->r_ifindex = -1;
write_unlock_bh(&dn_fib_rules_lock);
}
}
}
static void dn_fib_rules_attach(struct net_device *dev)
{
struct dn_fib_rule *r;
for(r = dn_fib_rules; r; r = r->r_next) {
if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
write_lock_bh(&dn_fib_rules_lock);
r->r_ifindex = dev->ifindex;
write_unlock_bh(&dn_fib_rules_lock);
}
}
}
static int dn_fib_rules_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct net_device *dev = ptr;
switch(event) {
case NETDEV_UNREGISTER:
dn_fib_rules_detach(dev);
dn_fib_sync_down(0, dev, 1);
case NETDEV_REGISTER:
dn_fib_rules_attach(dev);
dn_fib_sync_up(dev);
}
return NOTIFY_DONE;
}
static struct notifier_block dn_fib_rules_notifier = {
.notifier_call = dn_fib_rules_event,
};
static int dn_fib_fill_rule(struct sk_buff *skb, struct dn_fib_rule *r,
struct netlink_callback *cb, unsigned int flags)
{
struct rtmsg *rtm;
struct nlmsghdr *nlh;
unsigned char *b = skb->tail;
nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWRULE, sizeof(*rtm), flags);
rtm = NLMSG_DATA(nlh);
rtm->rtm_family = AF_DECnet;
rtm->rtm_dst_len = r->r_dst_len;
rtm->rtm_src_len = r->r_src_len;
rtm->rtm_tos = 0;
#ifdef CONFIG_DECNET_ROUTE_FWMARK
if (r->r_fwmark)
RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
#endif
rtm->rtm_table = r->r_table;
rtm->rtm_protocol = 0;
rtm->rtm_scope = 0;
rtm->rtm_type = r->r_action;
rtm->rtm_flags = r->r_flags;
if (r->r_dst_len)
RTA_PUT(skb, RTA_DST, 2, &r->r_dst);
if (r->r_src_len)
RTA_PUT(skb, RTA_SRC, 2, &r->r_src);
if (r->r_ifname[0])
RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
if (r->r_preference)
RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
if (r->r_srcmap)
RTA_PUT(skb, RTA_GATEWAY, 2, &r->r_srcmap);
nlh->nlmsg_len = skb->tail - b;
return skb->len;
nlmsg_failure:
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
int dn_fib_dump_rules(struct sk_buff *skb, struct netlink_callback *cb)
{
int idx;
int s_idx = cb->args[0];
struct dn_fib_rule *r;
read_lock(&dn_fib_rules_lock);
for(r = dn_fib_rules, idx = 0; r; r = r->r_next, idx++) {
if (idx < s_idx)
continue;
if (dn_fib_fill_rule(skb, r, cb, NLM_F_MULTI) < 0)
break;
}
read_unlock(&dn_fib_rules_lock);
cb->args[0] = idx;
return skb->len;
}
void __init dn_fib_rules_init(void)
{
register_netdevice_notifier(&dn_fib_rules_notifier);
}
void __exit dn_fib_rules_cleanup(void)
{
unregister_netdevice_notifier(&dn_fib_rules_notifier);
}