/* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. */ #ifndef _WG_QUEUEING_H #define _WG_QUEUEING_H #include "peer.h" #include #include #include #include #include struct wg_device; struct wg_peer; struct multicore_worker; struct crypt_queue; struct prev_queue; struct sk_buff; /* queueing.c APIs: */ int wg_packet_queue_init(struct crypt_queue *queue, work_func_t function, unsigned int len); void wg_packet_queue_free(struct crypt_queue *queue, bool purge); struct multicore_worker __percpu * wg_packet_percpu_multicore_worker_alloc(work_func_t function, void *ptr); /* receive.c APIs: */ void wg_packet_receive(struct wg_device *wg, struct sk_buff *skb); void wg_packet_handshake_receive_worker(struct work_struct *work); /* NAPI poll function: */ int wg_packet_rx_poll(struct napi_struct *napi, int budget); /* Workqueue worker: */ void wg_packet_decrypt_worker(struct work_struct *work); /* send.c APIs: */ void wg_packet_send_queued_handshake_initiation(struct wg_peer *peer, bool is_retry); void wg_packet_send_handshake_response(struct wg_peer *peer); void wg_packet_send_handshake_cookie(struct wg_device *wg, struct sk_buff *initiating_skb, __le32 sender_index); void wg_packet_send_keepalive(struct wg_peer *peer); void wg_packet_purge_staged_packets(struct wg_peer *peer); void wg_packet_send_staged_packets(struct wg_peer *peer); /* Workqueue workers: */ void wg_packet_handshake_send_worker(struct work_struct *work); void wg_packet_tx_worker(struct work_struct *work); void wg_packet_encrypt_worker(struct work_struct *work); enum packet_state { PACKET_STATE_UNCRYPTED, PACKET_STATE_CRYPTED, PACKET_STATE_DEAD }; struct packet_cb { u64 nonce; struct noise_keypair *keypair; atomic_t state; u32 mtu; u8 ds; }; #define PACKET_CB(skb) ((struct packet_cb *)((skb)->cb)) #define PACKET_PEER(skb) (PACKET_CB(skb)->keypair->entry.peer) static inline bool wg_check_packet_protocol(struct sk_buff *skb) { __be16 real_protocol = ip_tunnel_parse_protocol(skb); return real_protocol && skb->protocol == real_protocol; } static inline void wg_reset_packet(struct sk_buff *skb, bool encapsulating) { u8 l4_hash = skb->l4_hash; u8 sw_hash = skb->sw_hash; u32 hash = skb->hash; skb_scrub_packet(skb, true); memset(&skb->headers_start, 0, offsetof(struct sk_buff, headers_end) - offsetof(struct sk_buff, headers_start)); if (encapsulating) { skb->l4_hash = l4_hash; skb->sw_hash = sw_hash; skb->hash = hash; } skb->queue_mapping = 0; skb->nohdr = 0; skb->peeked = 0; skb->mac_len = 0; skb->dev = NULL; #ifdef CONFIG_NET_SCHED skb->tc_index = 0; #endif skb_reset_redirect(skb); skb->hdr_len = skb_headroom(skb); skb_reset_mac_header(skb); skb_reset_network_header(skb); skb_reset_transport_header(skb); skb_probe_transport_header(skb); skb_reset_inner_headers(skb); } static inline int wg_cpumask_choose_online(int *stored_cpu, unsigned int id) { unsigned int cpu = *stored_cpu, cpu_index, i; if (unlikely(cpu == nr_cpumask_bits || !cpumask_test_cpu(cpu, cpu_online_mask))) { cpu_index = id % cpumask_weight(cpu_online_mask); cpu = cpumask_first(cpu_online_mask); for (i = 0; i < cpu_index; ++i) cpu = cpumask_next(cpu, cpu_online_mask); *stored_cpu = cpu; } return cpu; } /* This function is racy, in the sense that next is unlocked, so it could return * the same CPU twice. A race-free version of this would be to instead store an * atomic sequence number, do an increment-and-return, and then iterate through * every possible CPU until we get to that index -- choose_cpu. However that's * a bit slower, and it doesn't seem like this potential race actually * introduces any performance loss, so we live with it. */ static inline int wg_cpumask_next_online(int *next) { int cpu = *next; while (unlikely(!cpumask_test_cpu(cpu, cpu_online_mask))) cpu = cpumask_next(cpu, cpu_online_mask) % nr_cpumask_bits; *next = cpumask_next(cpu, cpu_online_mask) % nr_cpumask_bits; return cpu; } void wg_prev_queue_init(struct prev_queue *queue); /* Multi producer */ bool wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb); /* Single consumer */ struct sk_buff *wg_prev_queue_dequeue(struct prev_queue *queue); /* Single consumer */ static inline struct sk_buff *wg_prev_queue_peek(struct prev_queue *queue) { if (queue->peeked) return queue->peeked; queue->peeked = wg_prev_queue_dequeue(queue); return queue->peeked; } /* Single consumer */ static inline void wg_prev_queue_drop_peeked(struct prev_queue *queue) { queue->peeked = NULL; } static inline int wg_queue_enqueue_per_device_and_peer( struct crypt_queue *device_queue, struct prev_queue *peer_queue, struct sk_buff *skb, struct workqueue_struct *wq, int *next_cpu) { int cpu; atomic_set_release(&PACKET_CB(skb)->state, PACKET_STATE_UNCRYPTED); /* We first queue this up for the peer ingestion, but the consumer * will wait for the state to change to CRYPTED or DEAD before. */ if (unlikely(!wg_prev_queue_enqueue(peer_queue, skb))) return -ENOSPC; /* Then we queue it up in the device queue, which consumes the * packet as soon as it can. */ cpu = wg_cpumask_next_online(next_cpu); if (unlikely(ptr_ring_produce_bh(&device_queue->ring, skb))) return -EPIPE; queue_work_on(cpu, wq, &per_cpu_ptr(device_queue->worker, cpu)->work); return 0; } static inline void wg_queue_enqueue_per_peer_tx(struct sk_buff *skb, enum packet_state state) { /* We take a reference, because as soon as we call atomic_set, the * peer can be freed from below us. */ struct wg_peer *peer = wg_peer_get(PACKET_PEER(skb)); atomic_set_release(&PACKET_CB(skb)->state, state); queue_work_on(wg_cpumask_choose_online(&peer->serial_work_cpu, peer->internal_id), peer->device->packet_crypt_wq, &peer->transmit_packet_work); wg_peer_put(peer); } static inline void wg_queue_enqueue_per_peer_rx(struct sk_buff *skb, enum packet_state state) { /* We take a reference, because as soon as we call atomic_set, the * peer can be freed from below us. */ struct wg_peer *peer = wg_peer_get(PACKET_PEER(skb)); atomic_set_release(&PACKET_CB(skb)->state, state); napi_schedule(&peer->napi); wg_peer_put(peer); } #ifdef DEBUG bool wg_packet_counter_selftest(void); #endif #endif /* _WG_QUEUEING_H */