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| | /* SPDX-License-Identifier: GPL-2.0-or-later
* Copyright Red Hat
* Author: Stefano Brivio <sbrivio@redhat.com>
* Author: David Gibson <david@gibson.dropbear.id.au>
*/
#ifndef FWD_H
#define FWD_H
union inany_addr;
struct flowside;
/* Number of ports for both TCP and UDP */
#define NUM_PORTS (1U << 16)
void fwd_probe_ephemeral(void);
bool fwd_port_is_ephemeral(in_port_t port);
/**
* struct fwd_entry - One range of ports to forward
* @addr: Address to forward from
* @ifname: Interface to forward from
* @first: First port number to forward
* @last: Last port number to forward
* @to: Port number to forward port @first to.
* @socks: Array of listening sockets for this entry
* @flags: Flag mask
* FWD_DUAL_STACK - forward both IPv4 and IPv6 (requires @addr be ::)
* FWD_WEAK - Don't give an error if binds fail for some forwards
* FWD_SCAN - Only forward if we scan a listener on the target
*
* FIXME: @addr and @ifname currently ignored for outbound tables
*/
struct fwd_entry {
union inany_addr addr;
char ifname[IFNAMSIZ];
in_port_t first, last, to;
int *socks;
#define FWD_DUAL_STACK BIT(0)
#define FWD_WEAK BIT(1)
#define FWD_SCAN BIT(2)
uint8_t flags;
};
#define MAX_FWDS 128
enum fwd_ports_mode {
FWD_UNSET = 0,
FWD_SPEC = 1,
FWD_NONE,
FWD_AUTO,
FWD_ALL,
};
#define PORT_BITMAP_SIZE DIV_ROUND_UP(NUM_PORTS, 8)
/* Maximum number of listening sockets (per pif & protocol)
*
* Rationale: This lets us listen on every port for two addresses (which we need
* for -T auto without SO_BINDTODEVICE), plus a comfortable number of extras.
*/
#define MAX_LISTEN_SOCKS (NUM_PORTS * 3)
/**
* fwd_ports() - Describes port forwarding for one protocol and direction
* @mode: Overall forwarding mode (all, none, auto, specific ports)
* @scan4: /proc/net fd to scan for IPv4 ports when in AUTO mode
* @scan6: /proc/net fd to scan for IPv6 ports when in AUTO mode
* @map: Bitmap describing which ports are forwarded
* @delta: Offset between the original destination and mapped port number
*/
struct fwd_ports {
enum fwd_ports_mode mode;
int scan4;
int scan6;
unsigned count;
struct fwd_entry tab[MAX_FWDS];
uint8_t map[PORT_BITMAP_SIZE];
in_port_t delta[NUM_PORTS];
unsigned listen_sock_count;
int listen_socks[MAX_LISTEN_SOCKS];
};
#define FWD_PORT_SCAN_INTERVAL 1000 /* ms */
void fwd_table_add(struct fwd_ports *fwd, uint8_t flags,
const union inany_addr *addr, const char *ifname,
in_port_t first, in_port_t last, in_port_t to);
void fwd_table_print(const struct fwd_ports *fwd);
void fwd_scan_ports_init(struct ctx *c);
void fwd_scan_ports_timer(struct ctx * c, const struct timespec *now);
void fwd_listen_sync(const struct ctx *c, const struct fwd_ports *fwd,
uint8_t pif, uint8_t proto);
bool nat_inbound(const struct ctx *c, const union inany_addr *addr,
union inany_addr *translated);
uint8_t fwd_nat_from_tap(const struct ctx *c, uint8_t proto,
const struct flowside *ini, struct flowside *tgt);
uint8_t fwd_nat_from_splice(const struct ctx *c, uint8_t proto,
const struct flowside *ini, struct flowside *tgt);
uint8_t fwd_nat_from_host(const struct ctx *c, uint8_t proto,
const struct flowside *ini, struct flowside *tgt);
void fwd_neigh_table_update(const struct ctx *c, const union inany_addr *addr,
const uint8_t *mac, bool permanent);
void fwd_neigh_table_free(const struct ctx *c,
const union inany_addr *addr);
void fwd_neigh_mac_get(const struct ctx *c, const union inany_addr *addr,
uint8_t *mac);
void fwd_neigh_table_init(const struct ctx *c);
#endif /* FWD_H */
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