/* * 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> #include <net/dn_route.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; }; 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 const struct nla_policy dn_fib_rule_policy[FRA_MAX+1] = { FRA_GENERIC_POLICY, }; 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; 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->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 (frh->src_len) r->src = nla_get_le16(tb[FRA_SRC]); if (frh->dst_len) r->dst = nla_get_le16(tb[FRA_DST]); 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 (frh->src_len && (r->src != nla_get_le16(tb[FRA_SRC]))) return 0; if (frh->dst_len && (r->dst != nla_get_le16(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->dst_len) NLA_PUT_LE16(skb, FRA_DST, r->dst); if (r->src_len) NLA_PUT_LE16(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; } static void dn_fib_rule_flush_cache(void) { dn_rt_cache_flush(-1); } static struct fib_rules_ops dn_fib_rules_ops = { .family = AF_DECnet, .rule_size = sizeof(struct dn_fib_rule), .addr_size = sizeof(u16), .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, .flush_cache = dn_fib_rule_flush_cache, .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); }