diff options
Diffstat (limited to 'include/net/psp/functions.h')
| -rw-r--r-- | include/net/psp/functions.h | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/include/net/psp/functions.h b/include/net/psp/functions.h new file mode 100644 index 000000000000..ef7743664da3 --- /dev/null +++ b/include/net/psp/functions.h @@ -0,0 +1,209 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __NET_PSP_HELPERS_H +#define __NET_PSP_HELPERS_H + +#include <linux/skbuff.h> +#include <linux/rcupdate.h> +#include <linux/udp.h> +#include <net/sock.h> +#include <net/tcp.h> +#include <net/psp/types.h> + +struct inet_timewait_sock; + +/* Driver-facing API */ +struct psp_dev * +psp_dev_create(struct net_device *netdev, struct psp_dev_ops *psd_ops, + struct psp_dev_caps *psd_caps, void *priv_ptr); +void psp_dev_unregister(struct psp_dev *psd); +bool psp_dev_encapsulate(struct net *net, struct sk_buff *skb, __be32 spi, + u8 ver, __be16 sport); +int psp_dev_rcv(struct sk_buff *skb, u16 dev_id, u8 generation, bool strip_icv); + +/* Kernel-facing API */ +void psp_assoc_put(struct psp_assoc *pas); + +static inline void *psp_assoc_drv_data(struct psp_assoc *pas) +{ + return pas->drv_data; +} + +#if IS_ENABLED(CONFIG_INET_PSP) +unsigned int psp_key_size(u32 version); +void psp_sk_assoc_free(struct sock *sk); +void psp_twsk_init(struct inet_timewait_sock *tw, const struct sock *sk); +void psp_twsk_assoc_free(struct inet_timewait_sock *tw); +void psp_reply_set_decrypted(struct sk_buff *skb); + +static inline struct psp_assoc *psp_sk_assoc(const struct sock *sk) +{ + return rcu_dereference_check(sk->psp_assoc, lockdep_sock_is_held(sk)); +} + +static inline void +psp_enqueue_set_decrypted(struct sock *sk, struct sk_buff *skb) +{ + struct psp_assoc *pas; + + pas = psp_sk_assoc(sk); + if (pas && pas->tx.spi) + skb->decrypted = 1; +} + +static inline unsigned long +__psp_skb_coalesce_diff(const struct sk_buff *one, const struct sk_buff *two, + unsigned long diffs) +{ + struct psp_skb_ext *a, *b; + + a = skb_ext_find(one, SKB_EXT_PSP); + b = skb_ext_find(two, SKB_EXT_PSP); + + diffs |= (!!a) ^ (!!b); + if (!diffs && unlikely(a)) + diffs |= memcmp(a, b, sizeof(*a)); + return diffs; +} + +static inline bool +psp_is_allowed_nondata(struct sk_buff *skb, struct psp_assoc *pas) +{ + bool fin = !!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN); + u32 end_seq = TCP_SKB_CB(skb)->end_seq; + u32 seq = TCP_SKB_CB(skb)->seq; + bool pure_fin; + + pure_fin = fin && end_seq - seq == 1; + + return seq == end_seq || (pure_fin && seq == pas->upgrade_seq); +} + +static inline bool +psp_pse_matches_pas(struct psp_skb_ext *pse, struct psp_assoc *pas) +{ + return pse && pas->rx.spi == pse->spi && + pas->generation == pse->generation && + pas->version == pse->version && + pas->dev_id == pse->dev_id; +} + +static inline enum skb_drop_reason +__psp_sk_rx_policy_check(struct sk_buff *skb, struct psp_assoc *pas) +{ + struct psp_skb_ext *pse = skb_ext_find(skb, SKB_EXT_PSP); + + if (!pas) + return pse ? SKB_DROP_REASON_PSP_INPUT : 0; + + if (likely(psp_pse_matches_pas(pse, pas))) { + if (unlikely(!pas->peer_tx)) + pas->peer_tx = 1; + + return 0; + } + + if (!pse) { + if (!pas->tx.spi || + (!pas->peer_tx && psp_is_allowed_nondata(skb, pas))) + return 0; + } + + return SKB_DROP_REASON_PSP_INPUT; +} + +static inline enum skb_drop_reason +psp_sk_rx_policy_check(struct sock *sk, struct sk_buff *skb) +{ + return __psp_sk_rx_policy_check(skb, psp_sk_assoc(sk)); +} + +static inline enum skb_drop_reason +psp_twsk_rx_policy_check(struct inet_timewait_sock *tw, struct sk_buff *skb) +{ + return __psp_sk_rx_policy_check(skb, rcu_dereference(tw->psp_assoc)); +} + +static inline struct psp_assoc *psp_sk_get_assoc_rcu(const struct sock *sk) +{ + struct psp_assoc *pas; + int state; + + state = READ_ONCE(sk->sk_state); + if (!sk_is_inet(sk) || state == TCP_NEW_SYN_RECV) + return NULL; + + pas = state == TCP_TIME_WAIT ? + rcu_dereference(inet_twsk(sk)->psp_assoc) : + rcu_dereference(sk->psp_assoc); + return pas; +} + +static inline struct psp_assoc *psp_skb_get_assoc_rcu(struct sk_buff *skb) +{ + if (!skb->decrypted || !skb->sk) + return NULL; + + return psp_sk_get_assoc_rcu(skb->sk); +} + +static inline unsigned int psp_sk_overhead(const struct sock *sk) +{ + int psp_encap = sizeof(struct udphdr) + PSP_HDR_SIZE + PSP_TRL_SIZE; + bool has_psp = rcu_access_pointer(sk->psp_assoc); + + return has_psp ? psp_encap : 0; +} +#else +static inline void psp_sk_assoc_free(struct sock *sk) { } +static inline void +psp_twsk_init(struct inet_timewait_sock *tw, const struct sock *sk) { } +static inline void psp_twsk_assoc_free(struct inet_timewait_sock *tw) { } +static inline void +psp_reply_set_decrypted(struct sk_buff *skb) { } + +static inline struct psp_assoc *psp_sk_assoc(const struct sock *sk) +{ + return NULL; +} + +static inline void +psp_enqueue_set_decrypted(struct sock *sk, struct sk_buff *skb) { } + +static inline unsigned long +__psp_skb_coalesce_diff(const struct sk_buff *one, const struct sk_buff *two, + unsigned long diffs) +{ + return diffs; +} + +static inline enum skb_drop_reason +psp_sk_rx_policy_check(struct sock *sk, struct sk_buff *skb) +{ + return 0; +} + +static inline enum skb_drop_reason +psp_twsk_rx_policy_check(struct inet_timewait_sock *tw, struct sk_buff *skb) +{ + return 0; +} + +static inline struct psp_assoc *psp_skb_get_assoc_rcu(struct sk_buff *skb) +{ + return NULL; +} + +static inline unsigned int psp_sk_overhead(const struct sock *sk) +{ + return 0; +} +#endif + +static inline unsigned long +psp_skb_coalesce_diff(const struct sk_buff *one, const struct sk_buff *two) +{ + return __psp_skb_coalesce_diff(one, two, 0); +} + +#endif /* __NET_PSP_HELPERS_H */ |