// Copyright 2018 The gVisor Authors.
//
// 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 GVISOR_TEST_SYSCALLS_IP_SOCKET_TEST_UTIL_H_
#define GVISOR_TEST_SYSCALLS_IP_SOCKET_TEST_UTIL_H_

#include <arpa/inet.h>
#include <ifaddrs.h>
#include <sys/types.h>

#include <string>

#include "test/syscalls/linux/socket_test_util.h"

namespace gvisor {
namespace testing {

// Possible values of the "st" field in a /proc/net/{tcp,udp} entry. Source:
// Linux kernel, include/net/tcp_states.h.
enum {
  TCP_ESTABLISHED = 1,
  TCP_SYN_SENT,
  TCP_SYN_RECV,
  TCP_FIN_WAIT1,
  TCP_FIN_WAIT2,
  TCP_TIME_WAIT,
  TCP_CLOSE,
  TCP_CLOSE_WAIT,
  TCP_LAST_ACK,
  TCP_LISTEN,
  TCP_CLOSING,
  TCP_NEW_SYN_RECV,

  TCP_MAX_STATES
};

// Extracts the IP address from an inet sockaddr in network byte order.
uint32_t IPFromInetSockaddr(const struct sockaddr* addr);

// Extracts the port from an inet sockaddr in host byte order.
uint16_t PortFromInetSockaddr(const struct sockaddr* addr);

// InterfaceIndex returns the index of the named interface.
PosixErrorOr<int> InterfaceIndex(std::string name);

// IPv6TCPAcceptBindSocketPair returns a SocketPairKind that represents
// SocketPairs created with bind() and accept() syscalls with AF_INET6 and the
// given type bound to the IPv6 loopback.
SocketPairKind IPv6TCPAcceptBindSocketPair(int type);

// IPv4TCPAcceptBindSocketPair returns a SocketPairKind that represents
// SocketPairs created with bind() and accept() syscalls with AF_INET and the
// given type bound to the IPv4 loopback.
SocketPairKind IPv4TCPAcceptBindSocketPair(int type);

// DualStackTCPAcceptBindSocketPair returns a SocketPairKind that represents
// SocketPairs created with bind() and accept() syscalls with AF_INET6 and the
// given type bound to the IPv4 loopback.
SocketPairKind DualStackTCPAcceptBindSocketPair(int type);

// IPv6UDPBidirectionalBindSocketPair returns a SocketPairKind that represents
// SocketPairs created with bind() and connect() syscalls with AF_INET6 and the
// given type bound to the IPv6 loopback.
SocketPairKind IPv6UDPBidirectionalBindSocketPair(int type);

// IPv4UDPBidirectionalBindSocketPair returns a SocketPairKind that represents
// SocketPairs created with bind() and connect() syscalls with AF_INET and the
// given type bound to the IPv4 loopback.
SocketPairKind IPv4UDPBidirectionalBindSocketPair(int type);

// DualStackUDPBidirectionalBindSocketPair returns a SocketPairKind that
// represents SocketPairs created with bind() and connect() syscalls with
// AF_INET6 and the given type bound to the IPv4 loopback.
SocketPairKind DualStackUDPBidirectionalBindSocketPair(int type);

// IPv4UDPUnboundSocketPair returns a SocketPairKind that represents
// SocketPairs created with AF_INET and the given type.
SocketPairKind IPv4UDPUnboundSocketPair(int type);

// IPv4UDPUnboundSocketPair returns a SocketKind that represents
// a SimpleSocket created with AF_INET, SOCK_DGRAM, and the given type.
SocketKind IPv4UDPUnboundSocket(int type);

// IPv4TCPUnboundSocketPair returns a SocketKind that represents
// a SimpleSocket created with AF_INET, SOCK_STREAM and the given type.
SocketKind IPv4TCPUnboundSocket(int type);

// IPv6TCPUnboundSocketPair returns a SocketKind that represents
// a SimpleSocket created with AF_INET6, SOCK_STREAM and the given type.
SocketKind IPv6TCPUnboundSocket(int type);

// IfAddrHelper is a helper class that determines the local interfaces present
// and provides functions to obtain their names, index numbers, and IP address.
class IfAddrHelper {
 public:
  IfAddrHelper() : ifaddr_(nullptr) {}
  ~IfAddrHelper() { Release(); }

  PosixError Load();
  void Release();

  std::vector<std::string> InterfaceList(int family);

  struct sockaddr* GetAddr(int family, std::string name);
  PosixErrorOr<int> GetIndex(std::string name);

 private:
  struct ifaddrs* ifaddr_;
};

// GetAddr4Str returns the given IPv4 network address structure as a string.
std::string GetAddr4Str(in_addr* a);

// GetAddr6Str returns the given IPv6 network address structure as a string.
std::string GetAddr6Str(in6_addr* a);

// GetAddrStr returns the given IPv4 or IPv6 network address structure as a
// string.
std::string GetAddrStr(sockaddr* a);

}  // namespace testing
}  // namespace gvisor

#endif  // GVISOR_TEST_SYSCALLS_IP_SOCKET_TEST_UTIL_H_