diff options
| -rw-r--r-- | include/net/ila.h | 18 | ||||
| -rw-r--r-- | include/uapi/linux/ila.h | 22 | ||||
| -rw-r--r-- | net/ipv6/ila/Makefile | 2 | ||||
| -rw-r--r-- | net/ipv6/ila/ila.h | 2 | ||||
| -rw-r--r-- | net/ipv6/ila/ila_common.c | 8 | ||||
| -rw-r--r-- | net/ipv6/ila/ila_xlat.c | 680 |
6 files changed, 731 insertions, 1 deletions
diff --git a/include/net/ila.h b/include/net/ila.h new file mode 100644 index 000000000000..9f4f43e94ae4 --- /dev/null +++ b/include/net/ila.h @@ -0,0 +1,18 @@ +/* + * ILA kernel interface + * + * Copyright (c) 2015 Tom Herbert <tom@herbertland.com> + * + * 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; either version 2 of + * the License, or (at your option) any later version. + */ + +#ifndef _NET_ILA_H +#define _NET_ILA_H + +int ila_xlat_outgoing(struct sk_buff *skb); +int ila_xlat_incoming(struct sk_buff *skb); + +#endif /* _NET_ILA_H */ diff --git a/include/uapi/linux/ila.h b/include/uapi/linux/ila.h index 7ed9e670814e..abde7bbd6f3b 100644 --- a/include/uapi/linux/ila.h +++ b/include/uapi/linux/ila.h @@ -3,13 +3,35 @@ #ifndef _UAPI_LINUX_ILA_H #define _UAPI_LINUX_ILA_H +/* NETLINK_GENERIC related info */ +#define ILA_GENL_NAME "ila" +#define ILA_GENL_VERSION 0x1 + enum { ILA_ATTR_UNSPEC, ILA_ATTR_LOCATOR, /* u64 */ + ILA_ATTR_IDENTIFIER, /* u64 */ + ILA_ATTR_LOCATOR_MATCH, /* u64 */ + ILA_ATTR_IFINDEX, /* s32 */ + ILA_ATTR_DIR, /* u32 */ __ILA_ATTR_MAX, }; #define ILA_ATTR_MAX (__ILA_ATTR_MAX - 1) +enum { + ILA_CMD_UNSPEC, + ILA_CMD_ADD, + ILA_CMD_DEL, + ILA_CMD_GET, + + __ILA_CMD_MAX, +}; + +#define ILA_CMD_MAX (__ILA_CMD_MAX - 1) + +#define ILA_DIR_IN (1 << 0) +#define ILA_DIR_OUT (1 << 1) + #endif /* _UAPI_LINUX_ILA_H */ diff --git a/net/ipv6/ila/Makefile b/net/ipv6/ila/Makefile index 31d136be2f21..4b32e5921e5c 100644 --- a/net/ipv6/ila/Makefile +++ b/net/ipv6/ila/Makefile @@ -4,4 +4,4 @@ obj-$(CONFIG_IPV6_ILA) += ila.o -ila-objs := ila_common.o ila_lwt.o +ila-objs := ila_common.o ila_lwt.o ila_xlat.o diff --git a/net/ipv6/ila/ila.h b/net/ipv6/ila/ila.h index b94081ff2f8a..28542cb2b387 100644 --- a/net/ipv6/ila/ila.h +++ b/net/ipv6/ila/ila.h @@ -42,5 +42,7 @@ void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p); int ila_lwt_init(void); void ila_lwt_fini(void); +int ila_xlat_init(void); +void ila_xlat_fini(void); #endif /* __ILA_H */ diff --git a/net/ipv6/ila/ila_common.c b/net/ipv6/ila/ila_common.c index 64e1904991ac..32dc9aab7297 100644 --- a/net/ipv6/ila/ila_common.c +++ b/net/ipv6/ila/ila_common.c @@ -80,12 +80,20 @@ static int __init ila_init(void) if (ret) goto fail_lwt; + ret = ila_xlat_init(); + if (ret) + goto fail_xlat; + + return 0; +fail_xlat: + ila_lwt_fini(); fail_lwt: return ret; } static void __exit ila_fini(void) { + ila_xlat_fini(); ila_lwt_fini(); } diff --git a/net/ipv6/ila/ila_xlat.c b/net/ipv6/ila/ila_xlat.c new file mode 100644 index 000000000000..295ca29a23c3 --- /dev/null +++ b/net/ipv6/ila/ila_xlat.c @@ -0,0 +1,680 @@ +#include <linux/jhash.h> +#include <linux/netfilter.h> +#include <linux/rcupdate.h> +#include <linux/rhashtable.h> +#include <linux/vmalloc.h> +#include <net/genetlink.h> +#include <net/ila.h> +#include <net/netns/generic.h> +#include <uapi/linux/genetlink.h> +#include "ila.h" + +struct ila_xlat_params { + struct ila_params ip; + __be64 identifier; + int ifindex; + unsigned int dir; +}; + +struct ila_map { + struct ila_xlat_params p; + struct rhash_head node; + struct ila_map __rcu *next; + struct rcu_head rcu; +}; + +static unsigned int ila_net_id; + +struct ila_net { + struct rhashtable rhash_table; + spinlock_t *locks; /* Bucket locks for entry manipulation */ + unsigned int locks_mask; + bool hooks_registered; +}; + +#define LOCKS_PER_CPU 10 + +static int alloc_ila_locks(struct ila_net *ilan) +{ + unsigned int i, size; + unsigned int nr_pcpus = num_possible_cpus(); + + nr_pcpus = min_t(unsigned int, nr_pcpus, 32UL); + size = roundup_pow_of_two(nr_pcpus * LOCKS_PER_CPU); + + if (sizeof(spinlock_t) != 0) { +#ifdef CONFIG_NUMA + if (size * sizeof(spinlock_t) > PAGE_SIZE) + ilan->locks = vmalloc(size * sizeof(spinlock_t)); + else +#endif + ilan->locks = kmalloc_array(size, sizeof(spinlock_t), + GFP_KERNEL); + if (!ilan->locks) + return -ENOMEM; + for (i = 0; i < size; i++) + spin_lock_init(&ilan->locks[i]); + } + ilan->locks_mask = size - 1; + + return 0; +} + +static u32 hashrnd __read_mostly; +static __always_inline void __ila_hash_secret_init(void) +{ + net_get_random_once(&hashrnd, sizeof(hashrnd)); +} + +static inline u32 ila_identifier_hash(__be64 identifier) +{ + u32 *v = (u32 *)&identifier; + + return jhash_2words(v[0], v[1], hashrnd); +} + +static inline spinlock_t *ila_get_lock(struct ila_net *ilan, __be64 identifier) +{ + return &ilan->locks[ila_identifier_hash(identifier) & ilan->locks_mask]; +} + +static inline int ila_cmp_wildcards(struct ila_map *ila, __be64 loc, + int ifindex, unsigned int dir) +{ + return (ila->p.ip.locator_match && ila->p.ip.locator_match != loc) || + (ila->p.ifindex && ila->p.ifindex != ifindex) || + !(ila->p.dir & dir); +} + +static inline int ila_cmp_params(struct ila_map *ila, struct ila_xlat_params *p) +{ + return (ila->p.ip.locator_match != p->ip.locator_match) || + (ila->p.ifindex != p->ifindex) || + (ila->p.dir != p->dir); +} + +static int ila_cmpfn(struct rhashtable_compare_arg *arg, + const void *obj) +{ + const struct ila_map *ila = obj; + + return (ila->p.identifier != *(__be64 *)arg->key); +} + +static inline int ila_order(struct ila_map *ila) +{ + int score = 0; + + if (ila->p.ip.locator_match) + score += 1 << 0; + + if (ila->p.ifindex) + score += 1 << 1; + + return score; +} + +static const struct rhashtable_params rht_params = { + .nelem_hint = 1024, + .head_offset = offsetof(struct ila_map, node), + .key_offset = offsetof(struct ila_map, p.identifier), + .key_len = sizeof(u64), /* identifier */ + .max_size = 1048576, + .min_size = 256, + .automatic_shrinking = true, + .obj_cmpfn = ila_cmpfn, +}; + +static struct genl_family ila_nl_family = { + .id = GENL_ID_GENERATE, + .hdrsize = 0, + .name = ILA_GENL_NAME, + .version = ILA_GENL_VERSION, + .maxattr = ILA_ATTR_MAX, + .netnsok = true, + .parallel_ops = true, +}; + +static struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = { + [ILA_ATTR_IDENTIFIER] = { .type = NLA_U64, }, + [ILA_ATTR_LOCATOR] = { .type = NLA_U64, }, + [ILA_ATTR_LOCATOR_MATCH] = { .type = NLA_U64, }, + [ILA_ATTR_IFINDEX] = { .type = NLA_U32, }, + [ILA_ATTR_DIR] = { .type = NLA_U32, }, +}; + +static int parse_nl_config(struct genl_info *info, + struct ila_xlat_params *p) +{ + memset(p, 0, sizeof(*p)); + + if (info->attrs[ILA_ATTR_IDENTIFIER]) + p->identifier = (__force __be64)nla_get_u64( + info->attrs[ILA_ATTR_IDENTIFIER]); + + if (info->attrs[ILA_ATTR_LOCATOR]) + p->ip.locator = (__force __be64)nla_get_u64( + info->attrs[ILA_ATTR_LOCATOR]); + + if (info->attrs[ILA_ATTR_LOCATOR_MATCH]) + p->ip.locator_match = (__force __be64)nla_get_u64( + info->attrs[ILA_ATTR_LOCATOR_MATCH]); + + if (info->attrs[ILA_ATTR_IFINDEX]) + p->ifindex = nla_get_s32(info->attrs[ILA_ATTR_IFINDEX]); + + if (info->attrs[ILA_ATTR_DIR]) + p->dir = nla_get_u32(info->attrs[ILA_ATTR_DIR]); + + return 0; +} + +/* Must be called with rcu readlock */ +static inline struct ila_map *ila_lookup_wildcards(__be64 id, __be64 loc, + int ifindex, + unsigned int dir, + struct ila_net *ilan) +{ + struct ila_map *ila; + + ila = rhashtable_lookup_fast(&ilan->rhash_table, &id, rht_params); + while (ila) { + if (!ila_cmp_wildcards(ila, loc, ifindex, dir)) + return ila; + ila = rcu_access_pointer(ila->next); + } + + return NULL; +} + +/* Must be called with rcu readlock */ +static inline struct ila_map *ila_lookup_by_params(struct ila_xlat_params *p, + struct ila_net *ilan) +{ + struct ila_map *ila; + + ila = rhashtable_lookup_fast(&ilan->rhash_table, &p->identifier, + rht_params); + while (ila) { + if (!ila_cmp_params(ila, p)) + return ila; + ila = rcu_access_pointer(ila->next); + } + + return NULL; +} + +static inline void ila_release(struct ila_map *ila) +{ + kfree_rcu(ila, rcu); +} + +static void ila_free_cb(void *ptr, void *arg) +{ + struct ila_map *ila = (struct ila_map *)ptr, *next; + + /* Assume rcu_readlock held */ + while (ila) { + next = rcu_access_pointer(ila->next); + ila_release(ila); + ila = next; + } +} + +static int ila_xlat_addr(struct sk_buff *skb, int dir); + +static unsigned int +ila_nf_input(void *priv, + struct sk_buff *skb, + const struct nf_hook_state *state) +{ + ila_xlat_addr(skb, ILA_DIR_IN); + return NF_ACCEPT; +} + +static struct nf_hook_ops ila_nf_hook_ops[] __read_mostly = { + { + .hook = ila_nf_input, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_PRE_ROUTING, + .priority = -1, + }, +}; + +static int ila_add_mapping(struct net *net, struct ila_xlat_params *p) +{ + struct ila_net *ilan = net_generic(net, ila_net_id); + struct ila_map *ila, *head; + spinlock_t *lock = ila_get_lock(ilan, p->identifier); + int err = 0, order; + + if (!ilan->hooks_registered) { + /* We defer registering net hooks in the namespace until the + * first mapping is added. + */ + err = nf_register_net_hooks(net, ila_nf_hook_ops, + ARRAY_SIZE(ila_nf_hook_ops)); + if (err) + return err; + + ilan->hooks_registered = true; + } + + ila = kzalloc(sizeof(*ila), GFP_KERNEL); + if (!ila) + return -ENOMEM; + + ila->p = *p; + + if (p->ip.locator_match) { + /* Precompute checksum difference for translation since we + * know both the old identifier and the new one. + */ + ila->p.ip.csum_diff = compute_csum_diff8( + (__be32 *)&p->ip.locator_match, + (__be32 *)&p->ip.locator); + } + + order = ila_order(ila); + + spin_lock(lock); + + head = rhashtable_lookup_fast(&ilan->rhash_table, &p->identifier, + rht_params); + if (!head) { + /* New entry for the rhash_table */ + err = rhashtable_lookup_insert_fast(&ilan->rhash_table, + &ila->node, rht_params); + } else { + struct ila_map *tila = head, *prev = NULL; + + do { + if (!ila_cmp_params(tila, p)) { + err = -EEXIST; + goto out; + } + + if (order > ila_order(tila)) + break; + + prev = tila; + tila = rcu_dereference_protected(tila->next, + lockdep_is_held(lock)); + } while (tila); + + if (prev) { + /* Insert in sub list of head */ + RCU_INIT_POINTER(ila->next, tila); + rcu_assign_pointer(prev->next, ila); + } else { + /* Make this ila new head */ + RCU_INIT_POINTER(ila->next, head); + err = rhashtable_replace_fast(&ilan->rhash_table, + &head->node, + &ila->node, rht_params); + if (err) + goto out; + } + } + +out: + spin_unlock(lock); + + if (err) + kfree(ila); + + return err; +} + +static int ila_del_mapping(struct net *net, struct ila_xlat_params *p) +{ + struct ila_net *ilan = net_generic(net, ila_net_id); + struct ila_map *ila, *head, *prev; + spinlock_t *lock = ila_get_lock(ilan, p->identifier); + int err = -ENOENT; + + spin_lock(lock); + + head = rhashtable_lookup_fast(&ilan->rhash_table, + &p->identifier, rht_params); + ila = head; + + prev = NULL; + + while (ila) { + if (ila_cmp_params(ila, p)) { + prev = ila; + ila = rcu_dereference_protected(ila->next, + lockdep_is_held(lock)); + continue; + } + + err = 0; + + if (prev) { + /* Not head, just delete from list */ + rcu_assign_pointer(prev->next, ila->next); + } else { + /* It is the head. If there is something in the + * sublist we need to make a new head. + */ + head = rcu_dereference_protected(ila->next, + lockdep_is_held(lock)); + if (head) { + /* Put first entry in the sublist into the + * table + */ + err = rhashtable_replace_fast( + &ilan->rhash_table, &ila->node, + &head->node, rht_params); + if (err) + goto out; + } else { + /* Entry no longer used */ + err = rhashtable_remove_fast(&ilan->rhash_table, + &ila->node, + rht_params); + } + } + + ila_release(ila); + + break; + } + +out: + spin_unlock(lock); + + return err; +} + +static int ila_nl_cmd_add_mapping(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct ila_xlat_params p; + int err; + + err = parse_nl_config(info, &p); + if (err) + return err; + + return ila_add_mapping(net, &p); +} + +static int ila_nl_cmd_del_mapping(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct ila_xlat_params p; + int err; + + err = parse_nl_config(info, &p); + if (err) + return err; + + ila_del_mapping(net, &p); + + return 0; +} + +static int ila_fill_info(struct ila_map *ila, struct sk_buff *msg) +{ + if (nla_put_u64(msg, ILA_ATTR_IDENTIFIER, + (__force u64)ila->p.identifier) || + nla_put_u64(msg, ILA_ATTR_LOCATOR, + (__force u64)ila->p.ip.locator) || + nla_put_u64(msg, ILA_ATTR_LOCATOR_MATCH, + (__force u64)ila->p.ip.locator_match) || + nla_put_s32(msg, ILA_ATTR_IFINDEX, ila->p.ifindex) || + nla_put_u32(msg, ILA_ATTR_DIR, ila->p.dir)) + return -1; + + return 0; +} + +static int ila_dump_info(struct ila_map *ila, + u32 portid, u32 seq, u32 flags, + struct sk_buff *skb, u8 cmd) +{ + void *hdr; + + hdr = genlmsg_put(skb, portid, seq, &ila_nl_family, flags, cmd); + if (!hdr) + return -ENOMEM; + + if (ila_fill_info(ila, skb) < 0) + goto nla_put_failure; + + genlmsg_end(skb, hdr); + return 0; + +nla_put_failure: + genlmsg_cancel(skb, hdr); + return -EMSGSIZE; +} + +static int ila_nl_cmd_get_mapping(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct ila_net *ilan = net_generic(net, ila_net_id); + struct sk_buff *msg; + struct ila_xlat_params p; + struct ila_map *ila; + int ret; + + ret = parse_nl_config(info, &p); + if (ret) + return ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + rcu_read_lock(); + + ila = ila_lookup_by_params(&p, ilan); + if (ila) { + ret = ila_dump_info(ila, + info->snd_portid, + info->snd_seq, 0, msg, + info->genlhdr->cmd); + } + + rcu_read_unlock(); + + if (ret < 0) + goto out_free; + + return genlmsg_reply(msg, info); + +out_free: + nlmsg_free(msg); + return ret; +} + +struct ila_dump_iter { + struct rhashtable_iter rhiter; +}; + +static int ila_nl_dump_start(struct netlink_callback *cb) +{ + struct net *net = sock_net(cb->skb->sk); + struct ila_net *ilan = net_generic(net, ila_net_id); + struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args; + + return rhashtable_walk_init(&ilan->rhash_table, &iter->rhiter); +} + +static int ila_nl_dump_done(struct netlink_callback *cb) +{ + struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args; + + rhashtable_walk_exit(&iter->rhiter); + + return 0; +} + +static int ila_nl_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args; + struct rhashtable_iter *rhiter = &iter->rhiter; + struct ila_map *ila; + int ret; + + ret = rhashtable_walk_start(rhiter); + if (ret && ret != -EAGAIN) + goto done; + + for (;;) { + ila = rhashtable_walk_next(rhiter); + + if (IS_ERR(ila)) { + if (PTR_ERR(ila) == -EAGAIN) + continue; + ret = PTR_ERR(ila); + goto done; + } else if (!ila) { + break; + } + + while (ila) { + ret = ila_dump_info(ila, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + skb, ILA_CMD_GET); + if (ret) + goto done; + + ila = rcu_access_pointer(ila->next); + } + } + + ret = skb->len; + +done: + rhashtable_walk_stop(rhiter); + return ret; +} + +static const struct genl_ops ila_nl_ops[] = { + { + .cmd = ILA_CMD_ADD, + .doit = ila_nl_cmd_add_mapping, + .policy = ila_nl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = ILA_CMD_DEL, + .doit = ila_nl_cmd_del_mapping, + .policy = ila_nl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = ILA_CMD_GET, + .doit = ila_nl_cmd_get_mapping, + .start = ila_nl_dump_start, + .dumpit = ila_nl_dump, + .done = ila_nl_dump_done, + .policy = ila_nl_policy, + }, +}; + +#define ILA_HASH_TABLE_SIZE 1024 + +static __net_init int ila_init_net(struct net *net) +{ + int err; + struct ila_net *ilan = net_generic(net, ila_net_id); + + err = alloc_ila_locks(ilan); + if (err) + return err; + + rhashtable_init(&ilan->rhash_table, &rht_params); + + return 0; +} + +static __net_exit void ila_exit_net(struct net *net) +{ + struct ila_net *ilan = net_generic(net, ila_net_id); + + rhashtable_free_and_destroy(&ilan->rhash_table, ila_free_cb, NULL); + + kvfree(ilan->locks); + + if (ilan->hooks_registered) + nf_unregister_net_hooks(net, ila_nf_hook_ops, + ARRAY_SIZE(ila_nf_hook_ops)); +} + +static struct pernet_operations ila_net_ops = { + .init = ila_init_net, + .exit = ila_exit_net, + .id = &ila_net_id, + .size = sizeof(struct ila_net), +}; + +static int ila_xlat_addr(struct sk_buff *skb, int dir) +{ + struct ila_map *ila; + struct ipv6hdr *ip6h = ipv6_hdr(skb); + struct net *net = dev_net(skb->dev); + struct ila_net *ilan = net_generic(net, ila_net_id); + __be64 identifier, locator_match; + size_t nhoff; + + /* Assumes skb contains a valid IPv6 header that is pulled */ + + identifier = *(__be64 *)&ip6h->daddr.in6_u.u6_addr8[8]; + locator_match = *(__be64 *)&ip6h->daddr.in6_u.u6_addr8[0]; + nhoff = sizeof(struct ipv6hdr); + + rcu_read_lock(); + + ila = ila_lookup_wildcards(identifier, locator_match, + skb->dev->ifindex, dir, ilan); + if (ila) + update_ipv6_locator(skb, &ila->p.ip); + + rcu_read_unlock(); + + return 0; +} + +int ila_xlat_incoming(struct sk_buff *skb) +{ + return ila_xlat_addr(skb, ILA_DIR_IN); +} +EXPORT_SYMBOL(ila_xlat_incoming); + +int ila_xlat_outgoing(struct sk_buff *skb) +{ + return ila_xlat_addr(skb, ILA_DIR_OUT); +} +EXPORT_SYMBOL(ila_xlat_outgoing); + +int ila_xlat_init(void) +{ + int ret; + + ret = register_pernet_device(&ila_net_ops); + if (ret) + goto exit; + + ret = genl_register_family_with_ops(&ila_nl_family, + ila_nl_ops); + if (ret < 0) + goto unregister; + + return 0; + +unregister: + unregister_pernet_device(&ila_net_ops); +exit: + return ret; +} + +void ila_xlat_fini(void) +{ + genl_unregister_family(&ila_nl_family); + unregister_pernet_device(&ila_net_ops); +} |