dn_table.rar_Table

/* * 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 (Routing Tables) * * Author: Steve Whitehouse <SteveW@ACM.org> * Mostly copied from the IPv4 routing code * * * Changes: * */ #include <linux/string.h> #include <linux/net.h> #include <linux/socket.h> #include <linux/slab.h> #include <linux/sockios.h> #include <linux/init.h> #include <linux/skbuff.h> #include <linux/rtnetlink.h> #include <linux/proc_fs.h> #include <linux/netdevice.h> #include <linux/timer.h> #include <linux/spinlock.h> #include <linux/atomic.h> #include <asm/uaccess.h> #include <linux/route.h> /* RTF_xxx */ #include <net/neighbour.h> #include <net/netlink.h> #include <net/dst.h> #include <net/flow.h> #include <net/fib_rules.h> #include <net/dn.h> #include <net/dn_route.h> #include <net/dn_fib.h> #include <net/dn_neigh.h> #include <net/dn_dev.h> struct dn_zone { struct dn_zone *dz_next; struct dn_fib_node **dz_hash; int dz_nent; int dz_divisor; u32 dz_hashmask; #define DZ_HASHMASK(dz) ((dz)->dz_hashmask) int dz_order; __le16 dz_mask; #define DZ_MASK(dz) ((dz)->dz_mask) }; struct dn_hash { struct dn_zone *dh_zones[17]; struct dn_zone *dh_zone_list; }; #define dz_key_0(key) ((key).datum = 0) #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\ for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++) #define endfor_nexthops(fi) } #define DN_MAX_DIVISOR 1024 #define DN_S_ZOMBIE 1 #define DN_S_ACCESSED 2 #define DN_FIB_SCAN(f, fp) \ for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next) #define DN_FIB_SCAN_KEY(f, fp, key) \ for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next) #define RT_TABLE_MIN 1 #define DN_FIB_TABLE_HASHSZ 256 static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ]; static DEFINE_RWLOCK(dn_fib_tables_lock); static struct kmem_cache *dn_hash_kmem __read_mostly; static int dn_fib_hash_zombies; static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz) { u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order); h ^= (h >> 10); h ^= (h >> 6); h &= DZ_HASHMASK(dz); return *(dn_fib_idx_t *)&h; } static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz) { dn_fib_key_t k; k.datum = dst & DZ_MASK(dz); return k; } static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz) { return &dz->dz_hash[dn_hash(key, dz).datum]; } static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz) { return dz->dz_hash[dn_hash(key, dz).datum]; } static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b) { return a.datum == b.datum; } static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b) { return a.datum <= b.datum; } static inline void dn_rebuild_zone(struct dn_zone *dz, struct dn_fib_node **old_ht, int old_divisor) { struct dn_fib_node *f, **fp, *next; int i; for(i = 0; i < old_divisor; i++) { for(f = old_ht[i]; f; f = next) { next = f->fn_next; for(fp = dn_chain_p(f->fn_key, dz); *fp && dn_key_leq((*fp)->fn_key, f->fn_key); fp = &(*fp)->fn_next) /* NOTHING */; f->fn_next = *fp; *fp = f; } } } static void dn_rehash_zone(struct dn_zone *dz) { struct dn_fib_node **ht, **old_ht; int old_divisor, new_divisor; u32 new_hashmask; old_divisor = dz->dz_divisor; switch (old_divisor) { case 16: new_divisor = 256; new_hashmask = 0xFF; break; default: printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n", old_divisor); case 256: new_divisor = 1024; new_hashmask = 0x3FF; break; } ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL); if (ht == NULL) return; write_lock_bh(&dn_fib_tables_lock); old_ht = dz->dz_hash; dz->dz_hash = ht; dz->dz_hashmask = new_hashmask; dz->dz_divisor = new_divisor; dn_rebuild_zone(dz, old_ht, old_divisor); write_unlock_bh(&dn_fib_tables_lock); kfree(old_ht); } static void dn_free_node(struct dn_fib_node *f) { dn_fib_release_info(DN_FIB_INFO(f)); kmem_cache_free(dn_hash_kmem, f); } static struct dn_zone *dn_new_zone(struct dn_hash *table, int z) { int i; struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL); if (!dz) return NULL; if (z) { dz->dz_divisor = 16; dz->dz_hashmask = 0x0F; } else { dz->dz_divisor = 1; dz->dz_hashmask = 0; } dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL); if (!dz->dz_hash) { kfree(dz); return NULL; } dz->dz_order = z; dz->dz_mask = dnet_make_mask(z); for(i = z + 1; i <= 16; i++) if (table->dh_zones[i]) break; write_lock_bh(&dn_fib_tables_lock); if (i>16) { dz->dz_next = table->dh_zone_list; table->dh_zone_list = dz; } else { dz->dz_next = table->dh_zones[i]->dz_next; table->dh_zones[i]->dz_next = dz; } table->dh_zones[z] = dz; write_unlock_bh(&dn_fib_tables_lock); return dz; } static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi) { struct rtnexthop *nhp; int nhlen; if (attrs[RTA_PRIORITY] && nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority) return 1; if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) { if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) && (!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw)) return 0; return 1; } if (!attrs[RTA_MULTIPATH]) return 0; nhp = nla_data(attrs[RTA_MULTIPATH]); nhlen = nla_len(attrs[RTA_MULTIPATH]); for_nexthops(fi) { int attrlen = nhlen - sizeof(struct rtnexthop); __le16 gw; if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0) return -EINVAL; if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif) return 1; if (attrlen) { struct nlattr *gw_attr; gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY); gw = gw_attr ? nla_get_le16(gw_attr) : 0; if (gw && gw != nh->nh_gw) return 1; } nhp = RTNH_NEXT(nhp); } endfor_nexthops(fi); return 0; } static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi) { size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) + nla_total_size(4) /* RTA_TABLE */ + nla_total_size(2) /* RTA_DST */ + nla_total_size(4); /* RTA_PRIORITY */ /* space for nested metrics */ payload += nla_total_size((RTAX_MAX * nla_total_size(4))); if (fi->fib_nhs) { /* Also handles the special case fib_nhs == 1 */ /* each nexthop is packed in an attribute */ size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); /* may contain a gateway attribute */ nhsize += nla_total_size(4); /* all nexthops are packed in a nested attribute */ payload += nla_total_size(fi->fib_nhs * nhsize); } return payload; } static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, u32 tb_id, u8 type, u8 scope, void *dst, int dst_len, struct dn_fib_info *fi, unsigned int flags) { struct rtmsg *rtm; struct nlmsghdr *nlh; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); if (!nlh) return -EMSGSIZE; rtm = nlmsg_data(nlh); rtm->rtm_family = AF_DECnet; rtm->rtm_dst_len = dst_len; rtm->rtm_src_len = 0; rtm->rtm_tos = 0; rtm->rtm_table = tb_id; rtm->rtm_flags = fi->fib_flags; rtm->rtm_scope = scope; rtm->rtm_type = type; rtm->rtm_protocol = fi->fib_protocol; if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0) goto errout; if (rtm->rtm_dst_len && nla_put(skb, RTA_DST, 2, dst) < 0) goto errout; if (fi->fib_priority && nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0) goto errout; if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) goto errout; if (fi->fib_nhs == 1) { if (fi->fib_nh->nh_gw && nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0) goto errout; if