From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- net/ipv6/fib6_rules.c | 337 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 337 insertions(+) create mode 100644 net/ipv6/fib6_rules.c (limited to 'net/ipv6/fib6_rules.c') diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c new file mode 100644 index 000000000..2367a16ea --- /dev/null +++ b/net/ipv6/fib6_rules.c @@ -0,0 +1,337 @@ +/* + * net/ipv6/fib6_rules.c IPv6 Routing Policy Rules + * + * Copyright (C)2003-2006 Helsinki University of Technology + * Copyright (C)2003-2006 USAGI/WIDE Project + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2. + * + * Authors + * Thomas Graf + * Ville Nuorvala + */ + +#include +#include + +#include +#include +#include +#include +#include + +struct fib6_rule { + struct fib_rule common; + struct rt6key src; + struct rt6key dst; + u8 tclass; +}; + +struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, + int flags, pol_lookup_t lookup) +{ + struct fib_lookup_arg arg = { + .lookup_ptr = lookup, + .flags = FIB_LOOKUP_NOREF, + }; + + fib_rules_lookup(net->ipv6.fib6_rules_ops, + flowi6_to_flowi(fl6), flags, &arg); + + if (arg.result) + return arg.result; + + dst_hold(&net->ipv6.ip6_null_entry->dst); + return &net->ipv6.ip6_null_entry->dst; +} + +static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp, + int flags, struct fib_lookup_arg *arg) +{ + struct flowi6 *flp6 = &flp->u.ip6; + struct rt6_info *rt = NULL; + struct fib6_table *table; + struct net *net = rule->fr_net; + pol_lookup_t lookup = arg->lookup_ptr; + int err = 0; + + switch (rule->action) { + case FR_ACT_TO_TBL: + break; + case FR_ACT_UNREACHABLE: + err = -ENETUNREACH; + rt = net->ipv6.ip6_null_entry; + goto discard_pkt; + default: + case FR_ACT_BLACKHOLE: + err = -EINVAL; + rt = net->ipv6.ip6_blk_hole_entry; + goto discard_pkt; + case FR_ACT_PROHIBIT: + err = -EACCES; + rt = net->ipv6.ip6_prohibit_entry; + goto discard_pkt; + } + + table = fib6_get_table(net, rule->table); + if (!table) { + err = -EAGAIN; + goto out; + } + + rt = lookup(net, table, flp6, flags); + if (rt != net->ipv6.ip6_null_entry) { + struct fib6_rule *r = (struct fib6_rule *)rule; + + /* + * If we need to find a source address for this traffic, + * we check the result if it meets requirement of the rule. + */ + if ((rule->flags & FIB_RULE_FIND_SADDR) && + r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) { + struct in6_addr saddr; + + if (ipv6_dev_get_saddr(net, + ip6_dst_idev(&rt->dst)->dev, + &flp6->daddr, + rt6_flags2srcprefs(flags), + &saddr)) + goto again; + if (!ipv6_prefix_equal(&saddr, &r->src.addr, + r->src.plen)) + goto again; + flp6->saddr = saddr; + } + err = rt->dst.error; + goto out; + } +again: + ip6_rt_put(rt); + err = -EAGAIN; + rt = NULL; + goto out; + +discard_pkt: + dst_hold(&rt->dst); +out: + arg->result = rt; + return err; +} + +static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg) +{ + struct rt6_info *rt = (struct rt6_info *) arg->result; + struct net_device *dev = NULL; + + if (rt->rt6i_idev) + dev = rt->rt6i_idev->dev; + + /* do not accept result if the route does + * not meet the required prefix length + */ + if (rt->rt6i_dst.plen <= rule->suppress_prefixlen) + goto suppress_route; + + /* do not accept result if the route uses a device + * belonging to a forbidden interface group + */ + if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup) + goto suppress_route; + + return false; + +suppress_route: + ip6_rt_put(rt); + return true; +} + +static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) +{ + struct fib6_rule *r = (struct fib6_rule *) rule; + struct flowi6 *fl6 = &fl->u.ip6; + + if (r->dst.plen && + !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen)) + return 0; + + /* + * If FIB_RULE_FIND_SADDR is set and we do not have a + * source address for the traffic, we defer check for + * source address. + */ + if (r->src.plen) { + if (flags & RT6_LOOKUP_F_HAS_SADDR) { + if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr, + r->src.plen)) + return 0; + } else if (!(r->common.flags & FIB_RULE_FIND_SADDR)) + return 0; + } + + if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel)) + return 0; + + return 1; +} + +static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = { + FRA_GENERIC_POLICY, +}; + +static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb, + struct fib_rule_hdr *frh, + struct nlattr **tb) +{ + int err = -EINVAL; + struct net *net = sock_net(skb->sk); + struct fib6_rule *rule6 = (struct fib6_rule *) rule; + + if (rule->action == FR_ACT_TO_TBL) { + if (rule->table == RT6_TABLE_UNSPEC) + goto errout; + + if (fib6_new_table(net, rule->table) == NULL) { + err = -ENOBUFS; + goto errout; + } + } + + if (frh->src_len) + rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]); + + if (frh->dst_len) + rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]); + + rule6->src.plen = frh->src_len; + rule6->dst.plen = frh->dst_len; + rule6->tclass = frh->tos; + + err = 0; +errout: + return err; +} + +static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, + struct nlattr **tb) +{ + struct fib6_rule *rule6 = (struct fib6_rule *) rule; + + if (frh->src_len && (rule6->src.plen != frh->src_len)) + return 0; + + if (frh->dst_len && (rule6->dst.plen != frh->dst_len)) + return 0; + + if (frh->tos && (rule6->tclass != frh->tos)) + return 0; + + if (frh->src_len && + nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr))) + return 0; + + if (frh->dst_len && + nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr))) + return 0; + + return 1; +} + +static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb, + struct fib_rule_hdr *frh) +{ + struct fib6_rule *rule6 = (struct fib6_rule *) rule; + + frh->dst_len = rule6->dst.plen; + frh->src_len = rule6->src.plen; + frh->tos = rule6->tclass; + + if ((rule6->dst.plen && + nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) || + (rule6->src.plen && + nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr))) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -ENOBUFS; +} + +static u32 fib6_rule_default_pref(struct fib_rules_ops *ops) +{ + return 0x3FFF; +} + +static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule) +{ + return nla_total_size(16) /* dst */ + + nla_total_size(16); /* src */ +} + +static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = { + .family = AF_INET6, + .rule_size = sizeof(struct fib6_rule), + .addr_size = sizeof(struct in6_addr), + .action = fib6_rule_action, + .match = fib6_rule_match, + .suppress = fib6_rule_suppress, + .configure = fib6_rule_configure, + .compare = fib6_rule_compare, + .fill = fib6_rule_fill, + .default_pref = fib6_rule_default_pref, + .nlmsg_payload = fib6_rule_nlmsg_payload, + .nlgroup = RTNLGRP_IPV6_RULE, + .policy = fib6_rule_policy, + .owner = THIS_MODULE, + .fro_net = &init_net, +}; + +static int __net_init fib6_rules_net_init(struct net *net) +{ + struct fib_rules_ops *ops; + int err = -ENOMEM; + + ops = fib_rules_register(&fib6_rules_ops_template, net); + if (IS_ERR(ops)) + return PTR_ERR(ops); + + err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0); + if (err) + goto out_fib6_rules_ops; + + err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0); + if (err) + goto out_fib6_rules_ops; + + net->ipv6.fib6_rules_ops = ops; +out: + return err; + +out_fib6_rules_ops: + fib_rules_unregister(ops); + goto out; +} + +static void __net_exit fib6_rules_net_exit(struct net *net) +{ + rtnl_lock(); + fib_rules_unregister(net->ipv6.fib6_rules_ops); + rtnl_unlock(); +} + +static struct pernet_operations fib6_rules_net_ops = { + .init = fib6_rules_net_init, + .exit = fib6_rules_net_exit, +}; + +int __init fib6_rules_init(void) +{ + return register_pernet_subsys(&fib6_rules_net_ops); +} + + +void fib6_rules_cleanup(void) +{ + unregister_pernet_subsys(&fib6_rules_net_ops); +} -- cgit v1.2.3-54-g00ecf