/*-
 * Copyright 2016 Vsevolod Stakhov
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef ADDR_H_
#define ADDR_H_

#include "config.h"
#include "rdns.h"

#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
/* unix sockets */
#ifdef HAVE_SYS_UN_H
#include <sys/un.h>
#endif

#include "mem_pool.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * Opaque structure
 */
typedef struct rspamd_inet_addr_s rspamd_inet_addr_t;

/**
 * Returns pointer storage for global singleton (map for local addresses)
 * @return
 */
void **rspamd_inet_library_init(void);
/**
 * Returns local addresses singleton
 * @return
 */
void *rspamd_inet_library_get_lib_ctx(void);
/**
 * Cleanup library (currently it does nothing)
 */
void rspamd_inet_library_destroy(void);

/**
 * Create new inet address structure based on the address family and opaque init pointer
 * @param af
 * @param init
 * @return new inet addr
 */
rspamd_inet_addr_t *rspamd_inet_address_new(int af, const void *init);

/**
 * Create new inet address structure from struct sockaddr
 * @param sa
 * @param slen
 * @return
 */
rspamd_inet_addr_t *rspamd_inet_address_from_sa(const struct sockaddr *sa,
												socklen_t slen);

/**
 * Create new inet address from rdns reply
 * @param rep reply element
 * @return new ipv4 or ipv6 addr (port is NOT set)
 */
rspamd_inet_addr_t *rspamd_inet_address_from_rnds(
	const struct rdns_reply_entry *rep);

/**
 * Parse string with ipv6 address of length `len` to `target` which should be
 * at least sizeof (struct in6_addr)
 * @param text input string
 * @param len length of `text` (if 0, then `text` must be zero terminated)
 * @param target target structure
 * @return TRUE if the address has been parsed, otherwise `target` content is undefined
 */
gboolean rspamd_parse_inet_address_ip6(const unsigned char *text, gsize len,
									   gpointer target);

enum rspamd_inet_address_parse_flags {
	RSPAMD_INET_ADDRESS_PARSE_DEFAULT = 0,
	RSPAMD_INET_ADDRESS_PARSE_REMOTE = 1u << 0u,
	RSPAMD_INET_ADDRESS_PARSE_NO_UNIX = 1u << 1u,
	RSPAMD_INET_ADDRESS_PARSE_NO_PORT = 1u << 2u,
};

/**
 * Parse string with ipv4 address of length `len` to `target` which should be
 * at least sizeof (in4_addr_t)
 * @param text input string
 * @param len length of `text` (if 0, then `text` must be zero terminated)
 * @param target target structure
 * @return TRUE if the address has been parsed, otherwise `target` content is undefined
 */
gboolean rspamd_parse_inet_address_ip4(const unsigned char *text, gsize len,
									   gpointer target);

/**
 * Parse ipv4 or ipv6 address to a static buffer `target`. Does not support Unix sockets
 * @param src
 * @param srclen
 * @param target
 * @return
 */
gboolean rspamd_parse_inet_address_ip(const char *src,
									  gsize srclen,
									  rspamd_inet_addr_t *target);

/**
 * Try to parse address from string
 * @param target target to fill
 * @param src IP string representation
 * @return TRUE if addr has been parsed
 */
gboolean rspamd_parse_inet_address(rspamd_inet_addr_t **target,
								   const char *src,
								   gsize srclen,
								   enum rspamd_inet_address_parse_flags how);

/**
 * Use memory pool allocated inet address
 * @param src
 * @param srclen
 * @param pool
 * @return
 */
rspamd_inet_addr_t *rspamd_parse_inet_address_pool(const char *src,
												   gsize srclen,
												   rspamd_mempool_t *pool,
												   enum rspamd_inet_address_parse_flags how);

/**
 * Returns string representation of inet address
 * @param addr
 * @return statically allocated string pointer (not thread safe)
 */
const char *rspamd_inet_address_to_string(const rspamd_inet_addr_t *addr);

/**
 * Returns pretty string representation of inet address
 * @param addr
 * @return statically allocated string pointer (not thread safe)
 */
const char *rspamd_inet_address_to_string_pretty(const rspamd_inet_addr_t *addr);

/**
 * Returns port number for the specified inet address in host byte order
 * @param addr
 * @return
 */
uint16_t rspamd_inet_address_get_port(const rspamd_inet_addr_t *addr);

/**
 * Returns address family of inet address
 * @param addr
 * @return
 */
int rspamd_inet_address_get_af(const rspamd_inet_addr_t *addr);

/**
 * Returns sockaddr and size for this address
 * @param addr
 * @param sz
 * @return
 */
struct sockaddr *rspamd_inet_address_get_sa(const rspamd_inet_addr_t *addr,
											socklen_t *sz);

/**
 * Makes a radix key from inet address
 * @param addr
 * @param klen
 * @return
 */
unsigned char *rspamd_inet_address_get_hash_key(const rspamd_inet_addr_t *addr, unsigned int *klen);

/**
 * Receive data from an unconnected socket and fill the inet_addr structure if needed
 * @param fd
 * @param buf
 * @param len
 * @param target
 * @return same as recvfrom(2)
 */
gssize rspamd_inet_address_recvfrom(int fd, void *buf, gsize len, int fl,
									rspamd_inet_addr_t **target);

/**
 * Send data via unconnected socket using the specified inet_addr structure
 * @param fd
 * @param buf
 * @param len
 * @param target
 * @return
 */
gssize rspamd_inet_address_sendto(int fd, const void *buf, gsize len, int fl,
								  const rspamd_inet_addr_t *addr);

/**
 * Set port for inet address
 */
void rspamd_inet_address_set_port(rspamd_inet_addr_t *addr, uint16_t port);

/**
 * Connect to inet_addr address
 * @param addr
 * @param async perform operations asynchronously
 * @return newly created and connected socket
 */
int rspamd_inet_address_connect(const rspamd_inet_addr_t *addr, int type,
								gboolean async);

enum rspamd_inet_address_listen_opts {
	RSPAMD_INET_ADDRESS_LISTEN_DEFAULT = 0,
	RSPAMD_INET_ADDRESS_LISTEN_ASYNC = (1u << 0u),
	RSPAMD_INET_ADDRESS_LISTEN_REUSEPORT = (1u << 1u),
	RSPAMD_INET_ADDRESS_LISTEN_NOLISTEN = (1u << 2u),
};
/**
 * Listen on a specified inet address
 * @param addr
 * @param type
 * @param opts
 * @return
 */
int rspamd_inet_address_listen(const rspamd_inet_addr_t *addr, int type,
							   enum rspamd_inet_address_listen_opts opts,
							   int listen_queue);

/**
 * Check whether specified ip is valid (not INADDR_ANY or INADDR_NONE) for ipv4 or ipv6
 * @param ptr pointer to struct in_addr or struct in6_addr
 * @param af address family (AF_INET or AF_INET6)
 * @return TRUE if the address is valid
 */
gboolean rspamd_ip_is_valid(const rspamd_inet_addr_t *addr);

typedef void (*rspamd_accept_throttling_handler)(int, void *);

/**
 * Accept from listening socket filling addr structure
 * @param sock listening socket
 * @param target allocated inet addr structure
 * @return
 */
int rspamd_accept_from_socket(int sock,
							  rspamd_inet_addr_t **target,
							  rspamd_accept_throttling_handler hdl,
							  void *hdl_data);

enum rspamd_parse_host_port_result {
	RSPAMD_PARSE_ADDR_FAIL = 0,
	RSPAMD_PARSE_ADDR_RESOLVED = 1,
	RSPAMD_PARSE_ADDR_NUMERIC = 2,
};
/**
 * Parse host[:port[:priority]] line
 * @param ina host address
 * @param port port
 * @param priority priority
 * @return RSPAMD_PARSE_ADDR_FAIL in case of error, RSPAMD_PARSE_ADDR_NUMERIC in case of pure ip/unix socket
 */
enum rspamd_parse_host_port_result
rspamd_parse_host_port_priority(const char *str,
								GPtrArray **addrs,
								unsigned int *priority, char **name,
								unsigned int default_port,
								gboolean allow_listen,
								rspamd_mempool_t *pool);

/**
 * Destroy the specified IP address
 * @param addr
 */
void rspamd_inet_address_free(rspamd_inet_addr_t *addr);

/**
 * Apply the specified mask to an address (ignored for AF_UNIX)
 * @param addr
 * @param mask
 */
void rspamd_inet_address_apply_mask(rspamd_inet_addr_t *addr, unsigned int mask);

/**
 * Compare a1 and a2 and return value >0, ==0 and <0 if a1 is more, equal or less than a2 correspondingly
 * @param a1
 * @param a2
 * @return
 */
int rspamd_inet_address_compare(const rspamd_inet_addr_t *a1,
								const rspamd_inet_addr_t *a2, gboolean compare_ports);

/**
 * Utility function to compare addresses by in g_ptr_array
 * @param a1
 * @param a2
 * @return
 */
int rspamd_inet_address_compare_ptr(gconstpointer a1,
									gconstpointer a2);

/**
 * Performs deep copy of rspamd inet addr
 * @param addr
 * @return
 */
rspamd_inet_addr_t *rspamd_inet_address_copy(const rspamd_inet_addr_t *addr, rspamd_mempool_t *pool);

/**
 * Returns hash for inet address (ignoring port)
 */
unsigned int rspamd_inet_address_hash(gconstpointer a);

unsigned int rspamd_inet_address_port_hash(gconstpointer a);

/**
 * Returns true if two address are equal
 */
gboolean rspamd_inet_address_equal(gconstpointer a, gconstpointer b);

gboolean rspamd_inet_address_port_equal(gconstpointer a, gconstpointer b);

/**
 * Returns TRUE if an address belongs to some local address
 */
gboolean rspamd_inet_address_is_local(const rspamd_inet_addr_t *addr);

/**
 * Returns size of storage required to store a complete IP address
 * @return
 */
gsize rspamd_inet_address_storage_size(void);

#ifdef __cplusplus
}
#endif

#endif /* ADDR_H_ */