/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim:set ts=4 sw=4 sts=4 et cin: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/net/DNS.h"

#include "mozilla/Assertions.h"

#include "mozilla/mozalloc.h"

#include "mozilla/ArrayUtils.h"

#include "nsString.h"

#include <string.h>

#ifdef XP_WIN

#include "ws2tcpip.h"

#endif

namespace mozilla {

namespace net {

const char *inet_ntop_internal(int af, const void *src, char *dst, socklen_t size)

{

#ifdef XP_WIN

  if (af == AF_INET) {

    struct sockaddr_in s;

    memset(&s, 0, sizeof(s));

    s.sin_family = AF_INET;

    memcpy(&s.sin_addr, src, sizeof(struct in_addr));

    int result = getnameinfo((struct sockaddr *)&s, sizeof(struct sockaddr_in),

                             dst, size, nullptr, 0, NI_NUMERICHOST);

    if (result == 0) {

      return dst;

    }

  }

  else if (af == AF_INET6) {

    struct sockaddr_in6 s;

    memset(&s, 0, sizeof(s));

    s.sin6_family = AF_INET6;

    memcpy(&s.sin6_addr, src, sizeof(struct in_addr6));

    int result = getnameinfo((struct sockaddr *)&s, sizeof(struct sockaddr_in6),

                             dst, size, nullptr, 0, NI_NUMERICHOST);

    if (result == 0) {

      return dst;

    }

  }

  return nullptr;

#else

  return inet_ntop(af, src, dst, size);

#endif

}

// Copies the contents of a PRNetAddr to a NetAddr.

// Does not do a ptr safety check!

void PRNetAddrToNetAddr(const PRNetAddr *prAddr, NetAddr *addr)

{

  if (prAddr->raw.family == PR_AF_INET) {

    addr->inet.family = AF_INET;

    addr->inet.port = prAddr->inet.port;

    addr->inet.ip = prAddr->inet.ip;

  }

  else if (prAddr->raw.family == PR_AF_INET6) {

    addr->inet6.family = AF_INET6;

    addr->inet6.port = prAddr->ipv6.port;

    addr->inet6.flowinfo = prAddr->ipv6.flowinfo;

    memcpy(&addr->inet6.ip, &prAddr->ipv6.ip, sizeof(addr->inet6.ip.u8));

    addr->inet6.scope_id = prAddr->ipv6.scope_id;

  }

#if defined(XP_UNIX)

  else if (prAddr->raw.family == PR_AF_LOCAL) {

    addr->local.family = AF_LOCAL;

    memcpy(addr->local.path, prAddr->local.path, sizeof(addr->local.path));

  }

#endif

}

// Copies the contents of a NetAddr to a PRNetAddr.

// Does not do a ptr safety check!

void NetAddrToPRNetAddr(const NetAddr *addr, PRNetAddr *prAddr)

{

  if (addr->raw.family == AF_INET) {

    prAddr->inet.family = PR_AF_INET;

    prAddr->inet.port = addr->inet.port;

    prAddr->inet.ip = addr->inet.ip;

  }

  else if (addr->raw.family == AF_INET6) {

    prAddr->ipv6.family = PR_AF_INET6;

    prAddr->ipv6.port = addr->inet6.port;

    prAddr->ipv6.flowinfo = addr->inet6.flowinfo;

    memcpy(&prAddr->ipv6.ip, &addr->inet6.ip, sizeof(addr->inet6.ip.u8));

    prAddr->ipv6.scope_id = addr->inet6.scope_id;

  }

#if defined(XP_UNIX)

  else if (addr->raw.family == AF_LOCAL) {

    prAddr->local.family = PR_AF_LOCAL;

    memcpy(prAddr->local.path, addr->local.path, sizeof(addr->local.path));

  }

#elif defined(XP_WIN)

  else if (addr->raw.family == AF_LOCAL) {

    prAddr->local.family = PR_AF_LOCAL;

    memcpy(prAddr->local.path, addr->local.path, sizeof(addr->local.path));

  }

#endif

}

bool NetAddrToString(const NetAddr *addr, char *buf, uint32_t bufSize)

{

  if (addr->raw.family == AF_INET) {

    if (bufSize < INET_ADDRSTRLEN) {

      return false;

    }

    struct in_addr nativeAddr = {};

    nativeAddr.s_addr = addr->inet.ip;

    return !!inet_ntop_internal(AF_INET, &nativeAddr, buf, bufSize);

  }

  if (addr->raw.family == AF_INET6) {

    if (bufSize < INET6_ADDRSTRLEN) {

      return false;

    }

    struct in6_addr nativeAddr = {};

    memcpy(&nativeAddr.s6_addr, &addr->inet6.ip, sizeof(addr->inet6.ip.u8));

    return !!inet_ntop_internal(AF_INET6, &nativeAddr, buf, bufSize);

  }

#if defined(XP_UNIX)

  else if (addr->raw.family == AF_LOCAL) {

    if (bufSize < sizeof(addr->local.path)) {

      // Many callers don't bother checking our return value, so

      // null-terminate just in case.

      if (bufSize > 0) {

          buf[0] = '\0';

      }

      return false;

    }

    // Usually, the size passed to memcpy should be the size of the

    // destination. Here, we know that the source is no larger than the

    // destination, so using the source's size is always safe, whereas

    // using the destination's size may cause us to read off the end of the

    // source.

    memcpy(buf, addr->local.path, sizeof(addr->local.path));

    return true;

  }

#endif

  return false;

}

bool IsLoopBackAddress(const NetAddr *addr)

{

  if (addr->raw.family == AF_INET) {

    return (addr->inet.ip == htonl(INADDR_LOOPBACK));

  }

  if (addr->raw.family == AF_INET6) {

    if (IPv6ADDR_IS_LOOPBACK(&addr->inet6.ip)) {

      return true;

    }

    if (IPv6ADDR_IS_V4MAPPED(&addr->inet6.ip) &&

             IPv6ADDR_V4MAPPED_TO_IPADDR(&addr->inet6.ip) == htonl(INADDR_LOOPBACK)) {

      return true;

    }

  }

  return false;

}

bool IsIPAddrAny(const NetAddr *addr)

{

  if (addr->raw.family == AF_INET) {

    if (addr->inet.ip == htonl(INADDR_ANY)) {

      return true;

    }

  }

  else if (addr->raw.family == AF_INET6) {

    if (IPv6ADDR_IS_UNSPECIFIED(&addr->inet6.ip)) {

      return true;

    }

    if (IPv6ADDR_IS_V4MAPPED(&addr->inet6.ip) &&

               IPv6ADDR_V4MAPPED_TO_IPADDR(&addr->inet6.ip) == htonl(INADDR_ANY)) {

      return true;

    }

  }

  return false;

}

bool IsIPAddrV4Mapped(const NetAddr *addr)

{

  if (addr->raw.family == AF_INET6) {

    return IPv6ADDR_IS_V4MAPPED(&addr->inet6.ip);

  }

  return false;

}

bool IsIPAddrLocal(const NetAddr *addr)

{

  MOZ_ASSERT(addr);

  // IPv4 RFC1918 and Link Local Addresses.

  if (addr->raw.family == AF_INET) {

    uint32_t addr32 = ntohl(addr->inet.ip);

    if (addr32 >> 24 == 0x0A ||    // 10/8 prefix (RFC 1918).

        addr32 >> 20 == 0xAC1 ||   // 172.16/12 prefix (RFC 1918).

        addr32 >> 16 == 0xC0A8 ||  // 192.168/16 prefix (RFC 1918).

        addr32 >> 16 == 0xA9FE) {  // 169.254/16 prefix (Link Local).

      return true;

    }

  }

  // IPv6 Unique and Link Local Addresses.

  if (addr->raw.family == AF_INET6) {

    uint16_t addr16 = ntohs(addr->inet6.ip.u16[0]);

    if (addr16 >> 9 == 0xfc >> 1 ||   // fc00::/7 Unique Local Address.

        addr16 >> 6 == 0xfe80 >> 6) { // fe80::/10 Link Local Address.

      return true;

    }

  }

  // Not an IPv4/6 local address.

  return false;

}

nsresult

GetPort(const NetAddr *aAddr, uint16_t *aResult)

{

  uint16_t port;

  if (aAddr->raw.family == PR_AF_INET) {

    port = aAddr->inet.port;

  } else if (aAddr->raw.family == PR_AF_INET6) {

    port = aAddr->inet6.port;

  } else {

    return NS_ERROR_NOT_INITIALIZED;

  }

  *aResult = ntohs(port);

  return NS_OK;

}

bool

NetAddr::operator == (const NetAddr& other) const

{

  if (this->raw.family != other.raw.family) {

    return false;

  }

  if (this->raw.family == AF_INET) {

    return (this->inet.port == other.inet.port) &&

           (this->inet.ip == other.inet.ip);

  }

  if (this->raw.family == AF_INET6) {

    return (this->inet6.port == other.inet6.port) &&

           (this->inet6.flowinfo == other.inet6.flowinfo) &&

           (memcmp(&this->inet6.ip, &other.inet6.ip,

                   sizeof(this->inet6.ip)) == 0) &&

           (this->inet6.scope_id == other.inet6.scope_id);

#if defined(XP_UNIX)

  }

  if (this->raw.family == AF_LOCAL) {

    return PL_strncmp(this->local.path, other.local.path,

                      ArrayLength(this->local.path));

#endif

  }

  return false;

}

bool

NetAddr::operator < (const NetAddr& other) const

{

    if (this->raw.family != other.raw.family) {

        return this->raw.family < other.raw.family;

    }

    if (this->raw.family == AF_INET) {

        if (this->inet.ip == other.inet.ip) {

            return this->inet.port < other.inet.port;

        }

        return this->inet.ip < other.inet.ip;

    }

    if (this->raw.family == AF_INET6) {

        int cmpResult = memcmp(&this->inet6.ip, &other.inet6.ip,

                               sizeof(this->inet6.ip));

        if (cmpResult) {

            return cmpResult < 0;

        }

        if (this->inet6.port != other.inet6.port) {

            return this->inet6.port < other.inet6.port;

        }

        return this->inet6.flowinfo < other.inet6.flowinfo;

    }

    return false;

}

NetAddrElement::NetAddrElement(const PRNetAddr *prNetAddr)

{

  this->mAddress.raw.family = 0;

  this->mAddress.inet = {};

  PRNetAddrToNetAddr(prNetAddr, &mAddress);

}

NetAddrElement::NetAddrElement(const NetAddrElement& netAddr)

{

  mAddress = netAddr.mAddress;

}

NetAddrElement::~NetAddrElement() = default;

AddrInfo::AddrInfo(const nsACString& host, const PRAddrInfo *prAddrInfo,

                   bool disableIPv4, bool filterNameCollision,

                   const nsACString& cname)

  : mHostName(host)

  , mCanonicalName(cname)

  , ttl(NO_TTL_DATA)

  , mFromTRR(false)

{

  MOZ_ASSERT(prAddrInfo, "Cannot construct AddrInfo with a null prAddrInfo pointer!");

  const uint32_t nameCollisionAddr = htonl(0x7f003535); // 127.0.53.53

  PRNetAddr tmpAddr;

  void *iter = nullptr;

  do {

    iter = PR_EnumerateAddrInfo(iter, prAddrInfo, 0, &tmpAddr);

    bool addIt = iter &&

        (!disableIPv4 || tmpAddr.raw.family != PR_AF_INET) &&

        (!filterNameCollision || tmpAddr.raw.family != PR_AF_INET || (tmpAddr.inet.ip != nameCollisionAddr));

    if (addIt) {

        auto *addrElement = new NetAddrElement(&tmpAddr);

        mAddresses.insertBack(addrElement);

    }

  } while (iter);

}

AddrInfo::AddrInfo(const nsACString& host, const nsACString& cname, unsigned int aTRR)

  : mHostName(host)

  , mCanonicalName(cname)

  , ttl(NO_TTL_DATA)

  , mFromTRR(aTRR)

{

}

AddrInfo::AddrInfo(const nsACString& host, unsigned int aTRR)

  : mHostName(host)

  , mCanonicalName(EmptyCString())

  , ttl(NO_TTL_DATA)

  , mFromTRR(aTRR)

{

}

// deep copy constructor

AddrInfo::AddrInfo(const AddrInfo *src)

{

  mHostName = src->mHostName;

  mCanonicalName = src->mCanonicalName;

  ttl = src->ttl;

  mFromTRR = src->mFromTRR;

  for (auto element = src->mAddresses.getFirst(); element;

       element = element->getNext()) {

    AddAddress(new NetAddrElement(*element));

  }

}

AddrInfo::~AddrInfo()

{

  NetAddrElement *addrElement;

  while ((addrElement = mAddresses.popLast())) {

    delete addrElement;

  }

}

void

AddrInfo::AddAddress(NetAddrElement *address)

{

  MOZ_ASSERT(address, "Cannot add the address to an uninitialized list");

  mAddresses.insertBack(address);

}

size_t

AddrInfo::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) const

{

  size_t n = mallocSizeOf(this);

  n += mHostName.SizeOfExcludingThisIfUnshared(mallocSizeOf);

  n += mCanonicalName.SizeOfExcludingThisIfUnshared(mallocSizeOf);

  n += mAddresses.sizeOfExcludingThis(mallocSizeOf);

  return n;

}

} // namespace net

} // namespace mozilla