/* SPDX-License-Identifier: AGPL-3.0-or-later
* Copyright (c) 2021 Red Hat GmbH
* Author: Stefano Brivio <sbrivio@redhat.com>
*/
#ifndef TCP_H
#define TCP_H
#define TCP_TIMER_INTERVAL 1000 /* ms */
#define TCP_CONN_INDEX_BITS 17 /* 128k */
#define TCP_MAX_CONNS (1 << TCP_CONN_INDEX_BITS)
#define TCP_MAX_SOCKS (TCP_MAX_CONNS + USHRT_MAX * 2)
#define TCP_SOCK_POOL_SIZE 32
struct ctx;
void tcp_sock_handler(struct ctx *c, union epoll_ref ref, uint32_t events,
const struct timespec *now);
int tcp_tap_handler(struct ctx *c, int af, const void *addr,
const struct pool *p, const struct timespec *now);
void tcp_sock_init(const struct ctx *c, int ns, sa_family_t af,
const void *addr, in_port_t port);
int tcp_init(struct ctx *c);
void tcp_timer(struct ctx *c, const struct timespec *ts);
void tcp_defer_handler(struct ctx *c);
void tcp_sock_set_bufsize(const struct ctx *c, int s);
void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s,
const uint32_t *ip_da);
void tcp_remap_to_tap(in_port_t port, in_port_t delta);
void tcp_remap_to_init(in_port_t port, in_port_t delta);
/**
* union tcp_epoll_ref - epoll reference portion for TCP connections
* @listen: Set if this file descriptor is a listening socket
* @splice: Set if descriptor is associated to a spliced connection
* @v6: Set for IPv6 sockets or connections
* @timer: Reference is a timerfd descriptor for connection
* @index: Index of connection in table, or port for bound sockets
* @u32: Opaque u32 value of reference
*/
union tcp_epoll_ref {
struct {
uint32_t listen:1,
splice:1,
v6:1,
timer:1,
index:20;
} tcp;
uint32_t u32;
};
/**
* struct tcp_ctx - Execution context for TCP routines
* @hash_secret: 128-bit secret for hash functions, ISN and hash table
* @conn_count: Count of connections (not spliced) in connection table
* @splice_conn_count: Count of spliced connections in connection table
* @port_to_tap: Ports bound host-side, packets to tap or spliced
* @fwd_mode_in: Port forwarding mode for inbound packets
* @port_to_init: Ports bound namespace-side, spliced to init
* @fwd_mode_out: Port forwarding mode for outbound packets
* @timer_run: Timestamp of most recent timer run
* @kernel_snd_wnd: Kernel reports sending window (with commit 8f7baad7f035)
* @pipe_size: Size of pipes for spliced connections
*/
struct tcp_ctx {
uint64_t hash_secret[2];
int conn_count;
int splice_conn_count;
uint8_t port_to_tap [PORT_BITMAP_SIZE];
enum port_fwd_mode fwd_mode_in;
uint8_t port_to_init [PORT_BITMAP_SIZE];
enum port_fwd_mode fwd_mode_out;
struct timespec timer_run;
#ifdef HAS_SND_WND
int kernel_snd_wnd;
#endif
size_t pipe_size;
};
#endif /* TCP_H */
