passt/tcp.h
David Gibson bb9bf0bb8f tcp, udp: Don't precompute port remappings in epoll references
The epoll references for both TCP listening sockets and UDP sockets
includes a port number.  This gives the destination port that traffic
to that socket will be sent to on the other side.  That will usually
be the same as the socket's bound port, but might not if the -t, -u,
-T or -U options are given with different original and forwarded port
numbers.

As we move towards a more flexible forwarding model for passt, it's
going to become possible for that destination port to vary depending
on more things (for example the source or destination address).  So,
it will no longer make sense to have a fixed value for a listening
socket.

Change to simpler semantics where this field in the reference gives
the bound port of the socket.  We apply the translations to the
correct destination port later on, when we're actually forwarding.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-02-29 09:47:40 +01:00

71 lines
2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-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 */
struct ctx;
void tcp_timer_handler(struct ctx *c, union epoll_ref ref);
void tcp_listen_handler(struct ctx *c, union epoll_ref ref,
const struct timespec *now);
void tcp_sock_handler(struct ctx *c, union epoll_ref ref, uint32_t events);
int tcp_tap_handler(struct ctx *c, uint8_t pif, sa_family_t af,
const void *saddr, const void *daddr,
const struct pool *p, int idx, const struct timespec *now);
int tcp_sock_init(const struct ctx *c, sa_family_t af, const void *addr,
const char *ifname, in_port_t port);
int tcp_init(struct ctx *c);
void tcp_timer(struct ctx *c, const struct timespec *now);
void tcp_defer_handler(struct ctx *c);
void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s);
/**
* union tcp_epoll_ref - epoll reference portion for TCP connections
* @index: Index of connection in table
* @u32: Opaque u32 value of reference
*/
union tcp_epoll_ref {
uint32_t index:20;
uint32_t u32;
};
/**
* union tcp_listen_epoll_ref - epoll reference portion for TCP listening
* @port: Bound port number of the socket
* @pif: pif in which the socket is listening
* @u32: Opaque u32 value of reference
*/
union tcp_listen_epoll_ref {
struct {
in_port_t port;
uint8_t pif;
};
uint32_t u32;
};
/**
* struct tcp_ctx - Execution context for TCP routines
* @port_to_tap: Ports bound host-side, packets to tap or spliced
* @fwd_in: Port forwarding configuration for inbound packets
* @fwd_out: Port forwarding configuration 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 {
struct port_fwd fwd_in;
struct port_fwd fwd_out;
struct timespec timer_run;
#ifdef HAS_SND_WND
int kernel_snd_wnd;
#endif
size_t pipe_size;
};
#endif /* TCP_H */