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Diffstat (limited to 'net/ipv4/fib_semantics.c')
-rw-r--r--net/ipv4/fib_semantics.c297
1 files changed, 159 insertions, 138 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 20f09c5b31e..3e0da3ef611 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -60,21 +60,30 @@ static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE];
static DEFINE_SPINLOCK(fib_multipath_lock);
-#define for_nexthops(fi) { int nhsel; const struct fib_nh * nh; \
-for (nhsel=0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
-
-#define change_nexthops(fi) { int nhsel; struct fib_nh *nexthop_nh; \
-for (nhsel=0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nexthop_nh++, nhsel++)
+#define for_nexthops(fi) { \
+ int nhsel; const struct fib_nh *nh; \
+ for (nhsel = 0, nh = (fi)->fib_nh; \
+ nhsel < (fi)->fib_nhs; \
+ nh++, nhsel++)
+
+#define change_nexthops(fi) { \
+ int nhsel; struct fib_nh *nexthop_nh; \
+ for (nhsel = 0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \
+ nhsel < (fi)->fib_nhs; \
+ nexthop_nh++, nhsel++)
#else /* CONFIG_IP_ROUTE_MULTIPATH */
/* Hope, that gcc will optimize it to get rid of dummy loop */
-#define for_nexthops(fi) { int nhsel = 0; const struct fib_nh * nh = (fi)->fib_nh; \
-for (nhsel=0; nhsel < 1; nhsel++)
+#define for_nexthops(fi) { \
+ int nhsel; const struct fib_nh *nh = (fi)->fib_nh; \
+ for (nhsel = 0; nhsel < 1; nhsel++)
-#define change_nexthops(fi) { int nhsel = 0; struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \
-for (nhsel=0; nhsel < 1; nhsel++)
+#define change_nexthops(fi) { \
+ int nhsel; \
+ struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \
+ for (nhsel = 0; nhsel < 1; nhsel++)
#endif /* CONFIG_IP_ROUTE_MULTIPATH */
@@ -86,63 +95,70 @@ static const struct
int error;
u8 scope;
} fib_props[RTN_MAX + 1] = {
- {
+ [RTN_UNSPEC] = {
.error = 0,
.scope = RT_SCOPE_NOWHERE,
- }, /* RTN_UNSPEC */
- {
+ },
+ [RTN_UNICAST] = {
.error = 0,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_UNICAST */
- {
+ },
+ [RTN_LOCAL] = {
.error = 0,
.scope = RT_SCOPE_HOST,
- }, /* RTN_LOCAL */
- {
+ },
+ [RTN_BROADCAST] = {
.error = 0,
.scope = RT_SCOPE_LINK,
- }, /* RTN_BROADCAST */
- {
+ },
+ [RTN_ANYCAST] = {
.error = 0,
.scope = RT_SCOPE_LINK,
- }, /* RTN_ANYCAST */
- {
+ },
+ [RTN_MULTICAST] = {
.error = 0,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_MULTICAST */
- {
+ },
+ [RTN_BLACKHOLE] = {
.error = -EINVAL,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_BLACKHOLE */
- {
+ },
+ [RTN_UNREACHABLE] = {
.error = -EHOSTUNREACH,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_UNREACHABLE */
- {
+ },
+ [RTN_PROHIBIT] = {
.error = -EACCES,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_PROHIBIT */
- {
+ },
+ [RTN_THROW] = {
.error = -EAGAIN,
.scope = RT_SCOPE_UNIVERSE,
- }, /* RTN_THROW */
- {
+ },
+ [RTN_NAT] = {
.error = -EINVAL,
.scope = RT_SCOPE_NOWHERE,
- }, /* RTN_NAT */
- {
+ },
+ [RTN_XRESOLVE] = {
.error = -EINVAL,
.scope = RT_SCOPE_NOWHERE,
- }, /* RTN_XRESOLVE */
+ },
};
/* Release a nexthop info record */
+static void free_fib_info_rcu(struct rcu_head *head)
+{
+ struct fib_info *fi = container_of(head, struct fib_info, rcu);
+
+ kfree(fi);
+}
+
void free_fib_info(struct fib_info *fi)
{
if (fi->fib_dead == 0) {
- printk(KERN_WARNING "Freeing alive fib_info %p\n", fi);
+ pr_warning("Freeing alive fib_info %p\n", fi);
return;
}
change_nexthops(fi) {
@@ -152,7 +168,7 @@ void free_fib_info(struct fib_info *fi)
} endfor_nexthops(fi);
fib_info_cnt--;
release_net(fi->fib_net);
- kfree(fi);
+ call_rcu(&fi->rcu, free_fib_info_rcu);
}
void fib_release_info(struct fib_info *fi)
@@ -173,7 +189,7 @@ void fib_release_info(struct fib_info *fi)
spin_unlock_bh(&fib_info_lock);
}
-static __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info *ofi)
+static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi)
{
const struct fib_nh *onh = ofi->fib_nh;
@@ -187,7 +203,7 @@ static __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info *
#ifdef CONFIG_NET_CLS_ROUTE
nh->nh_tclassid != onh->nh_tclassid ||
#endif
- ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
+ ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD))
return -1;
onh++;
} endfor_nexthops(fi);
@@ -238,7 +254,7 @@ static struct fib_info *fib_find_info(const struct fib_info *nfi)
nfi->fib_priority == fi->fib_priority &&
memcmp(nfi->fib_metrics, fi->fib_metrics,
sizeof(fi->fib_metrics)) == 0 &&
- ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
+ ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 &&
(nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
return fi;
}
@@ -247,9 +263,8 @@ static struct fib_info *fib_find_info(const struct fib_info *nfi)
}
/* Check, that the gateway is already configured.
- Used only by redirect accept routine.
+ * Used only by redirect accept routine.
*/
-
int ip_fib_check_default(__be32 gw, struct net_device *dev)
{
struct hlist_head *head;
@@ -264,7 +279,7 @@ int ip_fib_check_default(__be32 gw, struct net_device *dev)
hlist_for_each_entry(nh, node, head, nh_hash) {
if (nh->nh_dev == dev &&
nh->nh_gw == gw &&
- !(nh->nh_flags&RTNH_F_DEAD)) {
+ !(nh->nh_flags & RTNH_F_DEAD)) {
spin_unlock(&fib_info_lock);
return 0;
}
@@ -362,10 +377,10 @@ int fib_detect_death(struct fib_info *fi, int order,
}
if (state == NUD_REACHABLE)
return 0;
- if ((state&NUD_VALID) && order != dflt)
+ if ((state & NUD_VALID) && order != dflt)
return 0;
- if ((state&NUD_VALID) ||
- (*last_idx<0 && order > dflt)) {
+ if ((state & NUD_VALID) ||
+ (*last_idx < 0 && order > dflt)) {
*last_resort = fi;
*last_idx = order;
}
@@ -476,75 +491,76 @@ int fib_nh_match(struct fib_config *cfg, struct fib_info *fi)
/*
- Picture
- -------
-
- Semantics of nexthop is very messy by historical reasons.
- We have to take into account, that:
- a) gateway can be actually local interface address,
- so that gatewayed route is direct.
- b) gateway must be on-link address, possibly
- described not by an ifaddr, but also by a direct route.
- c) If both gateway and interface are specified, they should not
- contradict.
- d) If we use tunnel routes, gateway could be not on-link.
-
- Attempt to reconcile all of these (alas, self-contradictory) conditions
- results in pretty ugly and hairy code with obscure logic.
-
- I chose to generalized it instead, so that the size
- of code does not increase practically, but it becomes
- much more general.
- Every prefix is assigned a "scope" value: "host" is local address,
- "link" is direct route,
- [ ... "site" ... "interior" ... ]
- and "universe" is true gateway route with global meaning.
-
- Every prefix refers to a set of "nexthop"s (gw, oif),
- where gw must have narrower scope. This recursion stops
- when gw has LOCAL scope or if "nexthop" is declared ONLINK,
- which means that gw is forced to be on link.
-
- Code is still hairy, but now it is apparently logically
- consistent and very flexible. F.e. as by-product it allows
- to co-exists in peace independent exterior and interior
- routing processes.
-
- Normally it looks as following.
-
- {universe prefix} -> (gw, oif) [scope link]
- |
- |-> {link prefix} -> (gw, oif) [scope local]
- |
- |-> {local prefix} (terminal node)
+ * Picture
+ * -------
+ *
+ * Semantics of nexthop is very messy by historical reasons.
+ * We have to take into account, that:
+ * a) gateway can be actually local interface address,
+ * so that gatewayed route is direct.
+ * b) gateway must be on-link address, possibly
+ * described not by an ifaddr, but also by a direct route.
+ * c) If both gateway and interface are specified, they should not
+ * contradict.
+ * d) If we use tunnel routes, gateway could be not on-link.
+ *
+ * Attempt to reconcile all of these (alas, self-contradictory) conditions
+ * results in pretty ugly and hairy code with obscure logic.
+ *
+ * I chose to generalized it instead, so that the size
+ * of code does not increase practically, but it becomes
+ * much more general.
+ * Every prefix is assigned a "scope" value: "host" is local address,
+ * "link" is direct route,
+ * [ ... "site" ... "interior" ... ]
+ * and "universe" is true gateway route with global meaning.
+ *
+ * Every prefix refers to a set of "nexthop"s (gw, oif),
+ * where gw must have narrower scope. This recursion stops
+ * when gw has LOCAL scope or if "nexthop" is declared ONLINK,
+ * which means that gw is forced to be on link.
+ *
+ * Code is still hairy, but now it is apparently logically
+ * consistent and very flexible. F.e. as by-product it allows
+ * to co-exists in peace independent exterior and interior
+ * routing processes.
+ *
+ * Normally it looks as following.
+ *
+ * {universe prefix} -> (gw, oif) [scope link]
+ * |
+ * |-> {link prefix} -> (gw, oif) [scope local]
+ * |
+ * |-> {local prefix} (terminal node)
*/
-
static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
struct fib_nh *nh)
{
int err;
struct net *net;
+ struct net_device *dev;
net = cfg->fc_nlinfo.nl_net;
if (nh->nh_gw) {
struct fib_result res;
- if (nh->nh_flags&RTNH_F_ONLINK) {
- struct net_device *dev;
+ if (nh->nh_flags & RTNH_F_ONLINK) {
if (cfg->fc_scope >= RT_SCOPE_LINK)
return -EINVAL;
if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST)
return -EINVAL;
- if ((dev = __dev_get_by_index(net, nh->nh_oif)) == NULL)
+ dev = __dev_get_by_index(net, nh->nh_oif);
+ if (!dev)
return -ENODEV;
- if (!(dev->flags&IFF_UP))
+ if (!(dev->flags & IFF_UP))
return -ENETDOWN;
nh->nh_dev = dev;
dev_hold(dev);
nh->nh_scope = RT_SCOPE_LINK;
return 0;
}
+ rcu_read_lock();
{
struct flowi fl = {
.nl_u = {
@@ -559,50 +575,53 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
/* It is not necessary, but requires a bit of thinking */
if (fl.fl4_scope < RT_SCOPE_LINK)
fl.fl4_scope = RT_SCOPE_LINK;
- if ((err = fib_lookup(net, &fl, &res)) != 0)
+ err = fib_lookup(net, &fl, &res);
+ if (err) {
+ rcu_read_unlock();
return err;
+ }
}
err = -EINVAL;
if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
goto out;
nh->nh_scope = res.scope;
nh->nh_oif = FIB_RES_OIF(res);
- if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
+ nh->nh_dev = dev = FIB_RES_DEV(res);
+ if (!dev)
goto out;
- dev_hold(nh->nh_dev);
- err = -ENETDOWN;
- if (!(nh->nh_dev->flags & IFF_UP))
- goto out;
- err = 0;
-out:
- fib_res_put(&res);
- return err;
+ dev_hold(dev);
+ err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN;
} else {
struct in_device *in_dev;
- if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
+ if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK))
return -EINVAL;
+ rcu_read_lock();
+ err = -ENODEV;
in_dev = inetdev_by_index(net, nh->nh_oif);
if (in_dev == NULL)
- return -ENODEV;
- if (!(in_dev->dev->flags&IFF_UP)) {
- in_dev_put(in_dev);
- return -ENETDOWN;
- }
+ goto out;
+ err = -ENETDOWN;
+ if (!(in_dev->dev->flags & IFF_UP))
+ goto out;
nh->nh_dev = in_dev->dev;
dev_hold(nh->nh_dev);
nh->nh_scope = RT_SCOPE_HOST;
- in_dev_put(in_dev);
+ err = 0;
}
- return 0;
+out:
+ rcu_read_unlock();
+ return err;
}
static inline unsigned int fib_laddr_hashfn(__be32 val)
{
unsigned int mask = (fib_hash_size - 1);
- return ((__force u32)val ^ ((__force u32)val >> 7) ^ ((__force u32)val >> 14)) & mask;
+ return ((__force u32)val ^
+ ((__force u32)val >> 7) ^
+ ((__force u32)val >> 14)) & mask;
}
static struct hlist_head *fib_hash_alloc(int bytes)
@@ -611,7 +630,8 @@ static struct hlist_head *fib_hash_alloc(int bytes)
return kzalloc(bytes, GFP_KERNEL);
else
return (struct hlist_head *)
- __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(bytes));
+ __get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(bytes));
}
static void fib_hash_free(struct hlist_head *hash, int bytes)
@@ -806,7 +826,8 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
goto failure;
} else {
change_nexthops(fi) {
- if ((err = fib_check_nh(cfg, fi, nexthop_nh)) != 0)
+ err = fib_check_nh(cfg, fi, nexthop_nh);
+ if (err != 0)
goto failure;
} endfor_nexthops(fi)
}
@@ -819,7 +840,8 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
}
link_it:
- if ((ofi = fib_find_info(fi)) != NULL) {
+ ofi = fib_find_info(fi);
+ if (ofi) {
fi->fib_dead = 1;
free_fib_info(fi);
ofi->fib_treeref++;
@@ -864,7 +886,7 @@ failure:
/* Note! fib_semantic_match intentionally uses RCU list functions. */
int fib_semantic_match(struct list_head *head, const struct flowi *flp,
- struct fib_result *res, int prefixlen)
+ struct fib_result *res, int prefixlen, int fib_flags)
{
struct fib_alias *fa;
int nh_sel = 0;
@@ -879,7 +901,7 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp,
if (fa->fa_scope < flp->fl4_scope)
continue;
- fa->fa_state |= FA_S_ACCESSED;
+ fib_alias_accessed(fa);
err = fib_props[fa->fa_type].error;
if (err == 0) {
@@ -895,7 +917,7 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp,
case RTN_ANYCAST:
case RTN_MULTICAST:
for_nexthops(fi) {
- if (nh->nh_flags&RTNH_F_DEAD)
+ if (nh->nh_flags & RTNH_F_DEAD)
continue;
if (!flp->oif || flp->oif == nh->nh_oif)
break;
@@ -906,16 +928,15 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp,
goto out_fill_res;
}
#else
- if (nhsel < 1) {
+ if (nhsel < 1)
goto out_fill_res;
- }
#endif
endfor_nexthops(fi);
continue;
default:
- printk(KERN_WARNING "fib_semantic_match bad type %#x\n",
- fa->fa_type);
+ pr_warning("fib_semantic_match bad type %#x\n",
+ fa->fa_type);
return -EINVAL;
}
}
@@ -929,7 +950,8 @@ out_fill_res:
res->type = fa->fa_type;
res->scope = fa->fa_scope;
res->fi = fa->fa_info;
- atomic_inc(&res->fi->fib_clntref);
+ if (!(fib_flags & FIB_LOOKUP_NOREF))
+ atomic_inc(&res->fi->fib_clntref);
return 0;
}
@@ -1028,10 +1050,10 @@ nla_put_failure:
}
/*
- Update FIB if:
- - local address disappeared -> we must delete all the entries
- referring to it.
- - device went down -> we must shutdown all nexthops going via it.
+ * Update FIB if:
+ * - local address disappeared -> we must delete all the entries
+ * referring to it.
+ * - device went down -> we must shutdown all nexthops going via it.
*/
int fib_sync_down_addr(struct net *net, __be32 local)
{
@@ -1078,7 +1100,7 @@ int fib_sync_down_dev(struct net_device *dev, int force)
prev_fi = fi;
dead = 0;
change_nexthops(fi) {
- if (nexthop_nh->nh_flags&RTNH_F_DEAD)
+ if (nexthop_nh->nh_flags & RTNH_F_DEAD)
dead++;
else if (nexthop_nh->nh_dev == dev &&
nexthop_nh->nh_scope != scope) {
@@ -1110,10 +1132,9 @@ int fib_sync_down_dev(struct net_device *dev, int force)
#ifdef CONFIG_IP_ROUTE_MULTIPATH
/*
- Dead device goes up. We wake up dead nexthops.
- It takes sense only on multipath routes.
+ * Dead device goes up. We wake up dead nexthops.
+ * It takes sense only on multipath routes.
*/
-
int fib_sync_up(struct net_device *dev)
{
struct fib_info *prev_fi;
@@ -1123,7 +1144,7 @@ int fib_sync_up(struct net_device *dev)
struct fib_nh *nh;
int ret;
- if (!(dev->flags&IFF_UP))
+ if (!(dev->flags & IFF_UP))
return 0;
prev_fi = NULL;
@@ -1142,12 +1163,12 @@ int fib_sync_up(struct net_device *dev)
prev_fi = fi;
alive = 0;
change_nexthops(fi) {
- if (!(nexthop_nh->nh_flags&RTNH_F_DEAD)) {
+ if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) {
alive++;
continue;
}
if (nexthop_nh->nh_dev == NULL ||
- !(nexthop_nh->nh_dev->flags&IFF_UP))
+ !(nexthop_nh->nh_dev->flags & IFF_UP))
continue;
if (nexthop_nh->nh_dev != dev ||
!__in_dev_get_rtnl(dev))
@@ -1169,10 +1190,9 @@ int fib_sync_up(struct net_device *dev)
}
/*
- The algorithm is suboptimal, but it provides really
- fair weighted route distribution.
+ * The algorithm is suboptimal, but it provides really
+ * fair weighted route distribution.
*/
-
void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
{
struct fib_info *fi = res->fi;
@@ -1182,7 +1202,7 @@ void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
if (fi->fib_power <= 0) {
int power = 0;
change_nexthops(fi) {
- if (!(nexthop_nh->nh_flags&RTNH_F_DEAD)) {
+ if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) {
power += nexthop_nh->nh_weight;
nexthop_nh->nh_power = nexthop_nh->nh_weight;
}
@@ -1198,15 +1218,16 @@ void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
/* w should be random number [0..fi->fib_power-1],
- it is pretty bad approximation.
+ * it is pretty bad approximation.
*/
w = jiffies % fi->fib_power;
change_nexthops(fi) {
- if (!(nexthop_nh->nh_flags&RTNH_F_DEAD) &&
+ if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) &&
nexthop_nh->nh_power) {
- if ((w -= nexthop_nh->nh_power) <= 0) {
+ w -= nexthop_nh->nh_power;
+ if (w <= 0) {
nexthop_nh->nh_power--;
fi->fib_power--;
res->nh_sel = nhsel;