/* Copyright (c) 2018-2019, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file address_set.c
* \brief Implementation for a set of addresses.
*
* This module was first written on a semi-emergency basis to improve the
* robustness of the anti-DoS module. As such, it's written in a pretty
* conservative way, and should be susceptible to improvement later on.
**/
#include "orconfig.h"
#include "core/or/address_set.h"
#include "lib/net/address.h"
#include "lib/container/bloomfilt.h"
#include "lib/crypt_ops/crypto_rand.h"
#include "siphash.h"
/* Wrap our hash function to have the signature that the bloom filter
* needs. */
static uint64_t
bloomfilt_addr_hash(const struct sipkey *key,
const void *item)
{
return tor_addr_keyed_hash(key, item);
}
/**
* Allocate and return an address_set, suitable for holding up to
* max_address_guess distinct values.
*/
address_set_t *
address_set_new(int max_addresses_guess)
{
uint8_t k[BLOOMFILT_KEY_LEN];
crypto_rand((void*)k, sizeof(k));
return bloomfilt_new(max_addresses_guess, bloomfilt_addr_hash, k);
}
/**
* Add addr to set.
*
* All future queries for addr in set will return true. Removing
* items is not possible.
*/
void
address_set_add(address_set_t *set, const struct tor_addr_t *addr)
{
bloomfilt_add(set, addr);
}
/** As address_set_add(), but take an ipv4 address in host order. */
void
address_set_add_ipv4h(address_set_t *set, uint32_t addr)
{
tor_addr_t a;
tor_addr_from_ipv4h(&a, addr);
address_set_add(set, &a);
}
/**
* Return true if addr is a member of set. (And probably,
* return false if addr is not a member of set.)
*/
int
address_set_probably_contains(const address_set_t *set,
const struct tor_addr_t *addr)
{
return bloomfilt_probably_contains(set, addr);
}