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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>
*
* Forwarding rule definitions shared between passt/pasta and pesto
*/
#ifndef FWD_RULE_H
#define FWD_RULE_H
#include <stdint.h>
#include <net/if.h>
#include <netinet/in.h>
#include "ip.h"
#include "inany.h"
#include "bitmap.h"
/* Number of ports for both TCP and UDP */
#define NUM_PORTS (1U << 16)
#define PORT_BITMAP_SIZE DIV_ROUND_UP(NUM_PORTS, 8)
/* Forwarding capability bits */
#define FWD_CAP_IPV4 BIT(0)
#define FWD_CAP_IPV6 BIT(1)
#define FWD_CAP_TCP BIT(2)
#define FWD_CAP_UDP BIT(3)
#define FWD_CAP_SCAN BIT(4)
#define FWD_CAP_IFNAME BIT(5)
/**
* struct fwd_rule - Forwarding rule governing a range of ports
* @addr: Address to forward from
* @ifname: Interface to forward from
* @first: First port number to forward
* @last: Last port number to forward
* @to: Target port for @first, port n goes to @to + (n - @first)
* @proto: Protocol to forward
* @flags: Flag mask
* FWD_DUAL_STACK_ANY - match any IPv4 or IPv6 address (@addr should be ::)
* FWD_WEAK - Don't give an error if binds fail for some forwards
* FWD_SCAN - Only forward if the matching port in the target is listening
*/
struct fwd_rule {
union inany_addr addr;
char ifname[IFNAMSIZ];
in_port_t first;
in_port_t last;
in_port_t to;
uint8_t proto;
#define FWD_DUAL_STACK_ANY BIT(0)
#define FWD_WEAK BIT(1)
#define FWD_SCAN BIT(2)
uint8_t flags;
};
#define FWD_RULE_BITS 8
#define MAX_FWD_RULES MAX_FROM_BITS(FWD_RULE_BITS)
/* Maximum number of listening sockets (per pif)
*
* Rationale: This lets us listen on every port for two addresses and two
* protocols (which we need for -T auto -U auto without SO_BINDTODEVICE), plus a
* comfortable number of extras.
*/
#define MAX_LISTEN_SOCKS (NUM_PORTS * 5)
/**
* struct fwd_table - Forwarding state (per initiating pif)
* @caps: Forwarding capabilities for this initiating pif
* @count: Number of forwarding rules
* @rules: Array of forwarding rules
* @rulesocks: Parallel array of @rules (@count valid entries) of pointers to
* @socks entries giving the start of the corresponding rule's
* sockets within the larger array
* @sock_count: Number of entries used in @socks (for all rules combined)
* @socks: Listening sockets for forwarding
*/
struct fwd_table {
uint32_t caps;
unsigned count;
struct fwd_rule rules[MAX_FWD_RULES];
int *rulesocks[MAX_FWD_RULES];
unsigned sock_count;
int socks[MAX_LISTEN_SOCKS];
};
void fwd_probe_ephemeral(void);
#define FWD_RULE_STRLEN \
(IPPROTO_STRLEN - 1 \
+ INANY_ADDRSTRLEN - 1 \
+ IFNAMSIZ - 1 \
+ 4 * (UINT16_STRLEN - 1) \
+ sizeof(" []%:- => - (best effort) (auto-scan)"))
const union inany_addr *fwd_rule_addr(const struct fwd_rule *rule);
const char *fwd_rule_fmt(const struct fwd_rule *rule, char *dst, size_t size);
void fwd_rule_parse(char optname, const char *optarg, struct fwd_table *fwd);
/**
* fwd_rules_dump() - Dump forwarding rules
* @fn: Printing/logging function to call
* @rules: Array of rules to dump
* @count: Number of rules to dump
* @prefix: String to print at the start of each rule
* @suffix: String to print at the end of each rule
*/
#define fwd_rules_dump(fn, rules, count, prefix, suffix) \
do { \
unsigned i_; \
for (i_ = 0; i_ < (count); i_++) { \
char buf_[FWD_RULE_STRLEN]; \
fn("%s%s%s", prefix, \
fwd_rule_fmt(&(rules)[i_], buf_, sizeof(buf_)), \
suffix); \
} \
} while (0)
#endif /* FWD_RULE_H */
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