diff --git a/include/linux/lwtunnel.h b/include/linux/lwtunnel.h new file mode 100644 index 0000000000000000000000000000000000000000..97f32f8b4ae13ec38ae8c465f488d93305773640 --- /dev/null +++ b/include/linux/lwtunnel.h @@ -0,0 +1,6 @@ +#ifndef _LINUX_LWTUNNEL_H_ +#define _LINUX_LWTUNNEL_H_ + +#include + +#endif /* _LINUX_LWTUNNEL_H_ */ diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h new file mode 100644 index 0000000000000000000000000000000000000000..df24b3611ff49b17759dad1b0d2c1698f583a13c --- /dev/null +++ b/include/net/lwtunnel.h @@ -0,0 +1,132 @@ +#ifndef __NET_LWTUNNEL_H +#define __NET_LWTUNNEL_H 1 + +#include +#include +#include +#include +#include + +#define LWTUNNEL_HASH_BITS 7 +#define LWTUNNEL_HASH_SIZE (1 << LWTUNNEL_HASH_BITS) + +/* lw tunnel state flags */ +#define LWTUNNEL_STATE_OUTPUT_REDIRECT 0x1 + +struct lwtunnel_state { + __u16 type; + __u16 flags; + atomic_t refcnt; + int len; + __u8 data[0]; +}; + +struct lwtunnel_encap_ops { + int (*build_state)(struct net_device *dev, struct nlattr *encap, + struct lwtunnel_state **ts); + int (*output)(struct sock *sk, struct sk_buff *skb); + int (*fill_encap)(struct sk_buff *skb, + struct lwtunnel_state *lwtstate); + int (*get_encap_size)(struct lwtunnel_state *lwtstate); + int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b); +}; + +extern const struct lwtunnel_encap_ops __rcu * + lwtun_encaps[LWTUNNEL_ENCAP_MAX+1]; + +#ifdef CONFIG_LWTUNNEL +static inline void lwtunnel_state_get(struct lwtunnel_state *lws) +{ + atomic_inc(&lws->refcnt); +} + +static inline void lwtunnel_state_put(struct lwtunnel_state *lws) +{ + if (!lws) + return; + + if (atomic_dec_and_test(&lws->refcnt)) + kfree(lws); +} + +static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate) +{ + if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT)) + return true; + + return false; +} + +int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op, + unsigned int num); +int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op, + unsigned int num); +int lwtunnel_build_state(struct net_device *dev, u16 encap_type, + struct nlattr *encap, + struct lwtunnel_state **lws); +int lwtunnel_fill_encap(struct sk_buff *skb, + struct lwtunnel_state *lwtstate); +int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate); +struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len); +int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b); + +#else + +static inline void lwtunnel_state_get(struct lwtunnel_state *lws) +{ +} + +static inline void lwtunnel_state_put(struct lwtunnel_state *lws) +{ +} + +static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate) +{ + return false; +} + +static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op, + unsigned int num) +{ + return -EOPNOTSUPP; + +} + +static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op, + unsigned int num) +{ + return -EOPNOTSUPP; +} + +static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type, + struct nlattr *encap, + struct lwtunnel_state **lws) +{ + return -EOPNOTSUPP; +} + +static inline int lwtunnel_fill_encap(struct sk_buff *skb, + struct lwtunnel_state *lwtstate) +{ + return 0; +} + +static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate) +{ + return 0; +} + +static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len) +{ + return NULL; +} + +static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a, + struct lwtunnel_state *b) +{ + return 0; +} + +#endif + +#endif /* __NET_LWTUNNEL_H */ diff --git a/include/uapi/linux/lwtunnel.h b/include/uapi/linux/lwtunnel.h new file mode 100644 index 0000000000000000000000000000000000000000..aa611d931a313e222777f2201b3c97ab0fd697af --- /dev/null +++ b/include/uapi/linux/lwtunnel.h @@ -0,0 +1,15 @@ +#ifndef _UAPI_LWTUNNEL_H_ +#define _UAPI_LWTUNNEL_H_ + +#include + +enum lwtunnel_encap_types { + LWTUNNEL_ENCAP_NONE, + LWTUNNEL_ENCAP_MPLS, + __LWTUNNEL_ENCAP_MAX, +}; + +#define LWTUNNEL_ENCAP_MAX (__LWTUNNEL_ENCAP_MAX - 1) + + +#endif /* _UAPI_LWTUNNEL_H_ */ diff --git a/net/Kconfig b/net/Kconfig index 57a7c5af3175d1826f0708c551227e5e4281577e..7021c1bf44d6ce949091cb287232e6cfefed6256 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -374,6 +374,13 @@ source "net/caif/Kconfig" source "net/ceph/Kconfig" source "net/nfc/Kconfig" +config LWTUNNEL + bool "Network light weight tunnels" + ---help--- + This feature provides an infrastructure to support light weight + tunnels like mpls. There is no netdevice associated with a light + weight tunnel endpoint. Tunnel encapsulation parameters are stored + with light weight tunnel state associated with fib routes. endif # if NET diff --git a/net/core/Makefile b/net/core/Makefile index fec0856dd6c031a2ae369410fc5d7f9c25a1fcf6..086b01fbe1bd846e61db3e5a7efc183abf2186b6 100644 --- a/net/core/Makefile +++ b/net/core/Makefile @@ -23,3 +23,4 @@ obj-$(CONFIG_NETWORK_PHY_TIMESTAMPING) += timestamping.o obj-$(CONFIG_NET_PTP_CLASSIFY) += ptp_classifier.o obj-$(CONFIG_CGROUP_NET_PRIO) += netprio_cgroup.o obj-$(CONFIG_CGROUP_NET_CLASSID) += netclassid_cgroup.o +obj-$(CONFIG_LWTUNNEL) += lwtunnel.o diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c new file mode 100644 index 0000000000000000000000000000000000000000..d7ae3a235b4b08edb4ce3dcdaf64d80f24031f2d --- /dev/null +++ b/net/core/lwtunnel.c @@ -0,0 +1,179 @@ +/* + * lwtunnel Infrastructure for light weight tunnels like mpls + * + * Authors: Roopa Prabhu, + * + * 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. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +struct lwtunnel_state *lwtunnel_state_alloc(int encap_len) +{ + struct lwtunnel_state *lws; + + lws = kzalloc(sizeof(*lws) + encap_len, GFP_ATOMIC); + + return lws; +} +EXPORT_SYMBOL(lwtunnel_state_alloc); + +const struct lwtunnel_encap_ops __rcu * + lwtun_encaps[LWTUNNEL_ENCAP_MAX + 1] __read_mostly; + +int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *ops, + unsigned int num) +{ + if (num > LWTUNNEL_ENCAP_MAX) + return -ERANGE; + + return !cmpxchg((const struct lwtunnel_encap_ops **) + &lwtun_encaps[num], + NULL, ops) ? 0 : -1; +} +EXPORT_SYMBOL(lwtunnel_encap_add_ops); + +int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *ops, + unsigned int encap_type) +{ + int ret; + + if (encap_type == LWTUNNEL_ENCAP_NONE || + encap_type > LWTUNNEL_ENCAP_MAX) + return -ERANGE; + + ret = (cmpxchg((const struct lwtunnel_encap_ops **) + &lwtun_encaps[encap_type], + ops, NULL) == ops) ? 0 : -1; + + synchronize_net(); + + return ret; +} +EXPORT_SYMBOL(lwtunnel_encap_del_ops); + +int lwtunnel_build_state(struct net_device *dev, u16 encap_type, + struct nlattr *encap, struct lwtunnel_state **lws) +{ + const struct lwtunnel_encap_ops *ops; + int ret = -EINVAL; + + if (encap_type == LWTUNNEL_ENCAP_NONE || + encap_type > LWTUNNEL_ENCAP_MAX) + return ret; + + ret = -EOPNOTSUPP; + rcu_read_lock(); + ops = rcu_dereference(lwtun_encaps[encap_type]); + if (likely(ops && ops->build_state)) + ret = ops->build_state(dev, encap, lws); + rcu_read_unlock(); + + return ret; +} +EXPORT_SYMBOL(lwtunnel_build_state); + +int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate) +{ + const struct lwtunnel_encap_ops *ops; + struct nlattr *nest; + int ret = -EINVAL; + + if (!lwtstate) + return 0; + + if (lwtstate->type == LWTUNNEL_ENCAP_NONE || + lwtstate->type > LWTUNNEL_ENCAP_MAX) + return 0; + + ret = -EOPNOTSUPP; + nest = nla_nest_start(skb, RTA_ENCAP); + rcu_read_lock(); + ops = rcu_dereference(lwtun_encaps[lwtstate->type]); + if (likely(ops && ops->fill_encap)) + ret = ops->fill_encap(skb, lwtstate); + rcu_read_unlock(); + + if (ret) + goto nla_put_failure; + nla_nest_end(skb, nest); + ret = nla_put_u16(skb, RTA_ENCAP_TYPE, lwtstate->type); + if (ret) + goto nla_put_failure; + + return 0; + +nla_put_failure: + nla_nest_cancel(skb, nest); + + return (ret == -EOPNOTSUPP ? 0 : ret); +} +EXPORT_SYMBOL(lwtunnel_fill_encap); + +int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate) +{ + const struct lwtunnel_encap_ops *ops; + int ret = 0; + + if (!lwtstate) + return 0; + + if (lwtstate->type == LWTUNNEL_ENCAP_NONE || + lwtstate->type > LWTUNNEL_ENCAP_MAX) + return 0; + + rcu_read_lock(); + ops = rcu_dereference(lwtun_encaps[lwtstate->type]); + if (likely(ops && ops->get_encap_size)) + ret = nla_total_size(ops->get_encap_size(lwtstate)); + rcu_read_unlock(); + + return ret; +} +EXPORT_SYMBOL(lwtunnel_get_encap_size); + +int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) +{ + const struct lwtunnel_encap_ops *ops; + int ret = 0; + + if (!a && !b) + return 0; + + if (!a || !b) + return 1; + + if (a->type != b->type) + return 1; + + if (a->type == LWTUNNEL_ENCAP_NONE || + a->type > LWTUNNEL_ENCAP_MAX) + return 0; + + rcu_read_lock(); + ops = rcu_dereference(lwtun_encaps[a->type]); + if (likely(ops && ops->cmp_encap)) + ret = ops->cmp_encap(a, b); + rcu_read_unlock(); + + return ret; +} +EXPORT_SYMBOL(lwtunnel_cmp_encap);