* Authors: Thomas Graf <tgraf@suug.ch>
*/
-#include <linux/config.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/list.h>
module_put(ops->owner);
}
+static void flush_route_cache(struct fib_rules_ops *ops)
+{
+ if (ops->flush_cache)
+ ops->flush_cache();
+}
+
int fib_rules_register(struct fib_rules_ops *ops)
{
int err = -EEXIST;
EXPORT_SYMBOL_GPL(fib_rules_unregister);
+static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
+ struct flowi *fl, int flags)
+{
+ int ret = 0;
+
+ if (rule->ifindex && (rule->ifindex != fl->iif))
+ goto out;
+
+ if ((rule->mark ^ fl->mark) & rule->mark_mask)
+ goto out;
+
+ ret = ops->match(rule, fl, flags);
+out:
+ return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
+}
+
int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
int flags, struct fib_lookup_arg *arg)
{
rcu_read_lock();
list_for_each_entry_rcu(rule, ops->rules_list, list) {
- if (rule->ifindex && (rule->ifindex != fl->iif))
+jumped:
+ if (!fib_rule_match(rule, ops, fl, flags))
continue;
- if (!ops->match(rule, fl, flags))
+ if (rule->action == FR_ACT_GOTO) {
+ struct fib_rule *target;
+
+ target = rcu_dereference(rule->ctarget);
+ if (target == NULL) {
+ continue;
+ } else {
+ rule = target;
+ goto jumped;
+ }
+ } else if (rule->action == FR_ACT_NOP)
continue;
+ else
+ err = ops->action(rule, fl, flags, arg);
- err = ops->action(rule, fl, flags, arg);
if (err != -EAGAIN) {
fib_rule_get(rule);
arg->rule = rule;
}
}
- err = -ENETUNREACH;
+ err = -ESRCH;
out:
rcu_read_unlock();
EXPORT_SYMBOL_GPL(fib_rules_lookup);
-int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
+ struct fib_rules_ops *ops)
+{
+ int err = -EINVAL;
+
+ if (frh->src_len)
+ if (tb[FRA_SRC] == NULL ||
+ frh->src_len > (ops->addr_size * 8) ||
+ nla_len(tb[FRA_SRC]) != ops->addr_size)
+ goto errout;
+
+ if (frh->dst_len)
+ if (tb[FRA_DST] == NULL ||
+ frh->dst_len > (ops->addr_size * 8) ||
+ nla_len(tb[FRA_DST]) != ops->addr_size)
+ goto errout;
+
+ err = 0;
+errout:
+ return err;
+}
+
+static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct fib_rule_hdr *frh = nlmsg_data(nlh);
struct fib_rules_ops *ops = NULL;
struct fib_rule *rule, *r, *last = NULL;
struct nlattr *tb[FRA_MAX+1];
- int err = -EINVAL;
+ int err = -EINVAL, unresolved = 0;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
goto errout;
if (err < 0)
goto errout;
+ err = validate_rulemsg(frh, tb, ops);
+ if (err < 0)
+ goto errout;
+
rule = kzalloc(ops->rule_size, GFP_KERNEL);
if (rule == NULL) {
err = -ENOMEM;
rule->ifindex = dev->ifindex;
}
+ if (tb[FRA_FWMARK]) {
+ rule->mark = nla_get_u32(tb[FRA_FWMARK]);
+ if (rule->mark)
+ /* compatibility: if the mark value is non-zero all bits
+ * are compared unless a mask is explicitly specified.
+ */
+ rule->mark_mask = 0xFFFFFFFF;
+ }
+
+ if (tb[FRA_FWMASK])
+ rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
+
rule->action = frh->action;
rule->flags = frh->flags;
rule->table = frh_get_table(frh, tb);
if (!rule->pref && ops->default_pref)
rule->pref = ops->default_pref();
+ err = -EINVAL;
+ if (tb[FRA_GOTO]) {
+ if (rule->action != FR_ACT_GOTO)
+ goto errout_free;
+
+ rule->target = nla_get_u32(tb[FRA_GOTO]);
+ /* Backward jumps are prohibited to avoid endless loops */
+ if (rule->target <= rule->pref)
+ goto errout_free;
+
+ list_for_each_entry(r, ops->rules_list, list) {
+ if (r->pref == rule->target) {
+ rule->ctarget = r;
+ break;
+ }
+ }
+
+ if (rule->ctarget == NULL)
+ unresolved = 1;
+ } else if (rule->action == FR_ACT_GOTO)
+ goto errout_free;
+
err = ops->configure(rule, skb, nlh, frh, tb);
if (err < 0)
goto errout_free;
fib_rule_get(rule);
+ if (ops->unresolved_rules) {
+ /*
+ * There are unresolved goto rules in the list, check if
+ * any of them are pointing to this new rule.
+ */
+ list_for_each_entry(r, ops->rules_list, list) {
+ if (r->action == FR_ACT_GOTO &&
+ r->target == rule->pref) {
+ BUG_ON(r->ctarget != NULL);
+ rcu_assign_pointer(r->ctarget, rule);
+ if (--ops->unresolved_rules == 0)
+ break;
+ }
+ }
+ }
+
+ if (rule->action == FR_ACT_GOTO)
+ ops->nr_goto_rules++;
+
+ if (unresolved)
+ ops->unresolved_rules++;
+
if (last)
list_add_rcu(&rule->list, &last->list);
else
list_add_rcu(&rule->list, ops->rules_list);
notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
+ flush_route_cache(ops);
rules_ops_put(ops);
return 0;
return err;
}
-int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct fib_rule_hdr *frh = nlmsg_data(nlh);
struct fib_rules_ops *ops = NULL;
- struct fib_rule *rule;
+ struct fib_rule *rule, *tmp;
struct nlattr *tb[FRA_MAX+1];
int err = -EINVAL;
if (err < 0)
goto errout;
+ err = validate_rulemsg(frh, tb, ops);
+ if (err < 0)
+ goto errout;
+
list_for_each_entry(rule, ops->rules_list, list) {
if (frh->action && (frh->action != rule->action))
continue;
nla_strcmp(tb[FRA_IFNAME], rule->ifname))
continue;
+ if (tb[FRA_FWMARK] &&
+ (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
+ continue;
+
+ if (tb[FRA_FWMASK] &&
+ (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
+ continue;
+
if (!ops->compare(rule, frh, tb))
continue;
}
list_del_rcu(&rule->list);
+
+ if (rule->action == FR_ACT_GOTO)
+ ops->nr_goto_rules--;
+
+ /*
+ * Check if this rule is a target to any of them. If so,
+ * disable them. As this operation is eventually very
+ * expensive, it is only performed if goto rules have
+ * actually been added.
+ */
+ if (ops->nr_goto_rules > 0) {
+ list_for_each_entry(tmp, ops->rules_list, list) {
+ if (tmp->ctarget == rule) {
+ rcu_assign_pointer(tmp->ctarget, NULL);
+ ops->unresolved_rules++;
+ }
+ }
+ }
+
synchronize_rcu();
notify_rule_change(RTM_DELRULE, rule, ops, nlh,
NETLINK_CB(skb).pid);
fib_rule_put(rule);
+ flush_route_cache(ops);
rules_ops_put(ops);
return 0;
}
return err;
}
+static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
+ struct fib_rule *rule)
+{
+ size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
+ + nla_total_size(IFNAMSIZ) /* FRA_IFNAME */
+ + nla_total_size(4) /* FRA_PRIORITY */
+ + nla_total_size(4) /* FRA_TABLE */
+ + nla_total_size(4) /* FRA_FWMARK */
+ + nla_total_size(4); /* FRA_FWMASK */
+
+ if (ops->nlmsg_payload)
+ payload += ops->nlmsg_payload(rule);
+
+ return payload;
+}
+
static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
u32 pid, u32 seq, int type, int flags,
struct fib_rules_ops *ops)
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
if (nlh == NULL)
- return -1;
+ return -EMSGSIZE;
frh = nlmsg_data(nlh);
frh->table = rule->table;
frh->action = rule->action;
frh->flags = rule->flags;
- if (rule->ifname[0])
+ if (rule->action == FR_ACT_GOTO && rule->ctarget == NULL)
+ frh->flags |= FIB_RULE_UNRESOLVED;
+
+ if (rule->ifname[0]) {
NLA_PUT_STRING(skb, FRA_IFNAME, rule->ifname);
+ if (rule->ifindex == -1)
+ frh->flags |= FIB_RULE_DEV_DETACHED;
+ }
+
if (rule->pref)
NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
+ if (rule->mark)
+ NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
+
+ if (rule->mark_mask || rule->mark)
+ NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
+
+ if (rule->target)
+ NLA_PUT_U32(skb, FRA_GOTO, rule->target);
+
if (ops->fill(rule, skb, nlh, frh) < 0)
goto nla_put_failure;
return nlmsg_end(skb, nlh);
nla_put_failure:
- return nlmsg_cancel(skb, nlh);
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
}
-int fib_rules_dump(struct sk_buff *skb, struct netlink_callback *cb, int family)
+static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
+ struct fib_rules_ops *ops)
{
int idx = 0;
struct fib_rule *rule;
- struct fib_rules_ops *ops;
-
- ops = lookup_rules_ops(family);
- if (ops == NULL)
- return -EAFNOSUPPORT;
rcu_read_lock();
- list_for_each_entry(rule, ops->rules_list, list) {
- if (idx < cb->args[0])
+ list_for_each_entry_rcu(rule, ops->rules_list, list) {
+ if (idx < cb->args[1])
goto skip;
if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
idx++;
}
rcu_read_unlock();
- cb->args[0] = idx;
+ cb->args[1] = idx;
rules_ops_put(ops);
return skb->len;
}
-EXPORT_SYMBOL_GPL(fib_rules_dump);
+static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct fib_rules_ops *ops;
+ int idx = 0, family;
+
+ family = rtnl_msg_family(cb->nlh);
+ if (family != AF_UNSPEC) {
+ /* Protocol specific dump request */
+ ops = lookup_rules_ops(family);
+ if (ops == NULL)
+ return -EAFNOSUPPORT;
+
+ return dump_rules(skb, cb, ops);
+ }
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ops, &rules_ops, list) {
+ if (idx < cb->args[0] || !try_module_get(ops->owner))
+ goto skip;
+
+ if (dump_rules(skb, cb, ops) < 0)
+ break;
+
+ cb->args[1] = 0;
+ skip:
+ idx++;
+ }
+ rcu_read_unlock();
+ cb->args[0] = idx;
+
+ return skb->len;
+}
static void notify_rule_change(int event, struct fib_rule *rule,
struct fib_rules_ops *ops, struct nlmsghdr *nlh,
struct sk_buff *skb;
int err = -ENOBUFS;
- skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+ skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
if (skb == NULL)
goto errout;
err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
if (err < 0) {
+ /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
+ WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
-
err = rtnl_notify(skb, pid, ops->nlgroup, nlh, GFP_KERNEL);
errout:
if (err < 0)
static int __init fib_rules_init(void)
{
+ rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL);
+ rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL);
+ rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule);
+
return register_netdevice_notifier(&fib_rules_notifier);
}
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff