Add m-esr52 at 52.6.0

1 files changed, 369 insertions, 0 deletions

diff --git a/netwerk/dns/GetAddrInfo.cpp b/netwerk/dns/GetAddrInfo.cpp
new file mode 100644
index 000000000..3c177ec53
--- /dev/null
+++ b/netwerk/dns/GetAddrInfo.cpp
@@ -0,0 +1,369 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "GetAddrInfo.h"
+#include "mozilla/net/DNS.h"
+#include "prnetdb.h"
+#include "nsHostResolver.h"
+#include "nsError.h"
+#include "mozilla/Mutex.h"
+#include "nsAutoPtr.h"
+#include "mozilla/StaticPtr.h"
+#include "MainThreadUtils.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/net/DNS.h"
+#include <algorithm>
+#include "prerror.h"
+
+#include "mozilla/Logging.h"
+
+#if DNSQUERY_AVAILABLE
+// There is a bug in windns.h where the type of parameter ppQueryResultsSet for
+// DnsQuery_A is dependent on UNICODE being set. It should *always* be
+// PDNS_RECORDA, but if UNICODE is set it is PDNS_RECORDW. To get around this
+// we make sure that UNICODE is unset.
+#undef UNICODE
+#include <ws2tcpip.h>
+#undef GetAddrInfo
+#include <windns.h>
+#endif
+
+namespace mozilla {
+namespace net {
+
+static LazyLogModule gGetAddrInfoLog("GetAddrInfo");
+#define LOG(msg, ...) \
+  MOZ_LOG(gGetAddrInfoLog, LogLevel::Debug, ("[DNS]: " msg, ##__VA_ARGS__))
+#define LOG_WARNING(msg, ...) \
+  MOZ_LOG(gGetAddrInfoLog, LogLevel::Warning, ("[DNS]: " msg, ##__VA_ARGS__))
+
+#if DNSQUERY_AVAILABLE
+////////////////////////////
+// WINDOWS IMPLEMENTATION //
+////////////////////////////
+
+// Ensure consistency of PR_* and AF_* constants to allow for legacy usage of
+// PR_* constants with this API.
+static_assert(PR_AF_INET == AF_INET && PR_AF_INET6 == AF_INET6
+    && PR_AF_UNSPEC == AF_UNSPEC, "PR_AF_* must match AF_*");
+
+// We intentionally leak this mutex. This is because we can run into a
+// situation where the worker threads are still running until the process
+// is actually fully shut down, and at any time one of those worker
+// threads can access gDnsapiInfoLock.
+static OffTheBooksMutex* gDnsapiInfoLock = nullptr;
+
+struct DnsapiInfo
+{
+public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(DnsapiInfo);
+
+  HMODULE mLibrary;
+  decltype(&DnsQuery_A) mDnsQueryFunc;
+  decltype(&DnsFree) mDnsFreeFunc;
+
+private:
+  // This will either be called during shutdown of the GetAddrInfo module, or
+  // when a worker thread is done doing a lookup (ie: within
+  // _GetAddrInfo_Windows). Note that the lock must be held when this is
+  // called.
+  ~DnsapiInfo()
+  {
+    if (gDnsapiInfoLock) {
+      gDnsapiInfoLock->AssertCurrentThreadOwns();
+    } else {
+      MOZ_ASSERT_UNREACHABLE("No mutex available during GetAddrInfo "
+                             "shutdown.");
+      return;
+    }
+
+    LOG("Freeing Dnsapi.dll");
+    MOZ_ASSERT(mLibrary);
+    DebugOnly<BOOL> rv = FreeLibrary(mLibrary);
+    NS_WARNING_ASSERTION(rv, "Failed to free Dnsapi.dll.");
+  }
+};
+
+static StaticRefPtr<DnsapiInfo> gDnsapiInfo;
+
+static MOZ_ALWAYS_INLINE nsresult
+_GetAddrInfoInit_Windows()
+{
+  // This is necessary to ensure strict thread safety because if two threads
+  // run this function at the same time they can potentially create two
+  // mutexes.
+  MOZ_ASSERT(NS_IsMainThread(),
+             "Do not initialize GetAddrInfo off main thread!");
+
+  if (!gDnsapiInfoLock) {
+    gDnsapiInfoLock = new OffTheBooksMutex("GetAddrInfo.cpp::gDnsapiInfoLock");
+  }
+  OffTheBooksMutexAutoLock lock(*gDnsapiInfoLock);
+
+  if (gDnsapiInfo) {
+    MOZ_ASSERT_UNREACHABLE("GetAddrInfo is being initialized multiple times!");
+    return NS_ERROR_ALREADY_INITIALIZED;
+  }
+
+  HMODULE library = LoadLibraryA("Dnsapi.dll");
+  if (NS_WARN_IF(!library)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  FARPROC dnsQueryFunc = GetProcAddress(library, "DnsQuery_A");
+  FARPROC dnsFreeFunc = GetProcAddress(library, "DnsFree");
+  if (NS_WARN_IF(!dnsQueryFunc) || NS_WARN_IF(!dnsFreeFunc)) {
+    DebugOnly<BOOL> rv = FreeLibrary(library);
+    NS_WARNING_ASSERTION(rv, "Failed to free Dnsapi.dll.");
+    return NS_ERROR_FAILURE;
+  }
+
+  DnsapiInfo* info = new DnsapiInfo;
+  info->mLibrary = library;
+  info->mDnsQueryFunc = (decltype(info->mDnsQueryFunc)) dnsQueryFunc;
+  info->mDnsFreeFunc = (decltype(info->mDnsFreeFunc)) dnsFreeFunc;
+  gDnsapiInfo = info;
+
+  return NS_OK;
+}
+
+static MOZ_ALWAYS_INLINE nsresult
+_GetAddrInfoShutdown_Windows()
+{
+  OffTheBooksMutexAutoLock lock(*gDnsapiInfoLock);
+
+  if (NS_WARN_IF(!gDnsapiInfo) || NS_WARN_IF(!gDnsapiInfoLock)) {
+    MOZ_ASSERT_UNREACHABLE("GetAddrInfo not initialized!");
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  gDnsapiInfo = nullptr;
+
+  return NS_OK;
+}
+
+// If successful, returns in aResult a TTL value that is smaller or
+// equal with the one already there. Gets the TTL value by calling
+// to dnsapi->mDnsQueryFunc and iterating through the returned
+// records to find the one with the smallest TTL value.
+static MOZ_ALWAYS_INLINE nsresult
+_GetMinTTLForRequestType_Windows(DnsapiInfo * dnsapi, const char* aHost,
+                                 uint16_t aRequestType, unsigned int* aResult)
+{
+  MOZ_ASSERT(dnsapi);
+  MOZ_ASSERT(aHost);
+  MOZ_ASSERT(aResult);
+
+  PDNS_RECORDA dnsData = nullptr;
+  DNS_STATUS status = dnsapi->mDnsQueryFunc(
+    aHost,
+    aRequestType,
+    (DNS_QUERY_STANDARD | DNS_QUERY_NO_NETBT | DNS_QUERY_NO_HOSTS_FILE
+      | DNS_QUERY_NO_MULTICAST | DNS_QUERY_ACCEPT_TRUNCATED_RESPONSE
+      | DNS_QUERY_DONT_RESET_TTL_VALUES),
+    nullptr,
+    &dnsData,
+    nullptr);
+  if (status == DNS_INFO_NO_RECORDS || status == DNS_ERROR_RCODE_NAME_ERROR
+      || !dnsData) {
+    LOG("No DNS records found for %s. status=%X. aRequestType = %X\n",
+        aHost, status, aRequestType);
+    return NS_ERROR_FAILURE;
+  } else if (status != NOERROR) {
+    LOG_WARNING("DnsQuery_A failed with status %X.\n", status);
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  for (PDNS_RECORDA curRecord = dnsData; curRecord; curRecord = curRecord->pNext) {
+    // Only records in the answer section are important
+    if (curRecord->Flags.S.Section != DnsSectionAnswer) {
+      continue;
+    }
+
+    if (curRecord->wType == aRequestType) {
+      *aResult = std::min<unsigned int>(*aResult, curRecord->dwTtl);
+    } else {
+      LOG("Received unexpected record type %u in response for %s.\n",
+          curRecord->wType, aHost);
+    }
+  }
+
+  dnsapi->mDnsFreeFunc(dnsData, DNS_FREE_TYPE::DnsFreeRecordList);
+  return NS_OK;
+}
+
+static MOZ_ALWAYS_INLINE nsresult
+_GetTTLData_Windows(const char* aHost, uint16_t* aResult, uint16_t aAddressFamily)
+{
+  MOZ_ASSERT(aHost);
+  MOZ_ASSERT(aResult);
+  if (aAddressFamily != PR_AF_UNSPEC &&
+      aAddressFamily != PR_AF_INET &&
+      aAddressFamily != PR_AF_INET6) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<DnsapiInfo> dnsapi = nullptr;
+  {
+    OffTheBooksMutexAutoLock lock(*gDnsapiInfoLock);
+    dnsapi = gDnsapiInfo;
+  }
+
+  if (!dnsapi) {
+    LOG_WARNING("GetAddrInfo has been shutdown or has not been initialized.");
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  // In order to avoid using ANY records which are not always implemented as a
+  // "Gimme what you have" request in hostname resolvers, we should send A
+  // and/or AAAA requests, based on the address family requested.
+  unsigned int ttl = -1;
+  if (aAddressFamily == PR_AF_UNSPEC || aAddressFamily == PR_AF_INET) {
+    _GetMinTTLForRequestType_Windows(dnsapi, aHost, DNS_TYPE_A, &ttl);
+  }
+  if (aAddressFamily == PR_AF_UNSPEC || aAddressFamily == PR_AF_INET6) {
+    _GetMinTTLForRequestType_Windows(dnsapi, aHost, DNS_TYPE_AAAA, &ttl);
+  }
+
+  {
+    // dnsapi's destructor is not thread-safe, so we release explicitly here
+    OffTheBooksMutexAutoLock lock(*gDnsapiInfoLock);
+    dnsapi = nullptr;
+  }
+
+  if (ttl == -1) {
+    LOG("No useable TTL found.");
+    return NS_ERROR_FAILURE;
+  }
+
+  *aResult = ttl;
+  return NS_OK;
+}
+#endif
+
+////////////////////////////////////
+// PORTABLE RUNTIME IMPLEMENTATION//
+////////////////////////////////////
+
+static MOZ_ALWAYS_INLINE nsresult
+_GetAddrInfo_Portable(const char* aCanonHost, uint16_t aAddressFamily,
+                      uint16_t aFlags, const char* aNetworkInterface,
+                      AddrInfo** aAddrInfo)
+{
+  MOZ_ASSERT(aCanonHost);
+  MOZ_ASSERT(aAddrInfo);
+
+  // We accept the same aFlags that nsHostResolver::ResolveHost accepts, but we
+  // need to translate the aFlags into a form that PR_GetAddrInfoByName
+  // accepts.
+  int prFlags = PR_AI_ADDRCONFIG;
+  if (!(aFlags & nsHostResolver::RES_CANON_NAME)) {
+    prFlags |= PR_AI_NOCANONNAME;
+  }
+
+  // We need to remove IPv4 records manually because PR_GetAddrInfoByName
+  // doesn't support PR_AF_INET6.
+  bool disableIPv4 = aAddressFamily == PR_AF_INET6;
+  if (disableIPv4) {
+    aAddressFamily = PR_AF_UNSPEC;
+  }
+
+  PRAddrInfo* prai = PR_GetAddrInfoByName(aCanonHost, aAddressFamily, prFlags);
+
+  if (!prai) {
+    return NS_ERROR_UNKNOWN_HOST;
+  }
+
+  const char* canonName = nullptr;
+  if (aFlags & nsHostResolver::RES_CANON_NAME) {
+    canonName = PR_GetCanonNameFromAddrInfo(prai);
+  }
+
+  bool filterNameCollision = !(aFlags & nsHostResolver::RES_ALLOW_NAME_COLLISION);
+  nsAutoPtr<AddrInfo> ai(new AddrInfo(aCanonHost, prai, disableIPv4,
+                                      filterNameCollision, canonName));
+  PR_FreeAddrInfo(prai);
+  if (ai->mAddresses.isEmpty()) {
+    return NS_ERROR_UNKNOWN_HOST;
+  }
+
+  *aAddrInfo = ai.forget();
+
+  return NS_OK;
+}
+
+//////////////////////////////////////
+// COMMON/PLATFORM INDEPENDENT CODE //
+//////////////////////////////////////
+nsresult
+GetAddrInfoInit() {
+  LOG("Initializing GetAddrInfo.\n");
+
+#if DNSQUERY_AVAILABLE
+  return _GetAddrInfoInit_Windows();
+#else
+  return NS_OK;
+#endif
+}
+
+nsresult
+GetAddrInfoShutdown() {
+  LOG("Shutting down GetAddrInfo.\n");
+
+#if DNSQUERY_AVAILABLE
+  return _GetAddrInfoShutdown_Windows();
+#else
+  return NS_OK;
+#endif
+}
+
+nsresult
+GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
+            const char* aNetworkInterface, AddrInfo** aAddrInfo, bool aGetTtl)
+{
+  if (NS_WARN_IF(!aHost) || NS_WARN_IF(!aAddrInfo)) {
+    return NS_ERROR_NULL_POINTER;
+  }
+
+#if DNSQUERY_AVAILABLE
+  // The GetTTLData needs the canonical name to function properly
+  if (aGetTtl) {
+    aFlags |= nsHostResolver::RES_CANON_NAME;
+  }
+#endif
+
+  *aAddrInfo = nullptr;
+  nsresult rv = _GetAddrInfo_Portable(aHost, aAddressFamily, aFlags,
+                                      aNetworkInterface, aAddrInfo);
+
+#if DNSQUERY_AVAILABLE
+  if (aGetTtl && NS_SUCCEEDED(rv)) {
+    // Figure out the canonical name, or if that fails, just use the host name
+    // we have.
+    const char *name = nullptr;
+    if (*aAddrInfo != nullptr && (*aAddrInfo)->mCanonicalName) {
+      name = (*aAddrInfo)->mCanonicalName;
+    } else {
+      name = aHost;
+    }
+
+    LOG("Getting TTL for %s (cname = %s).", aHost, name);
+    uint16_t ttl = 0;
+    nsresult ttlRv = _GetTTLData_Windows(name, &ttl, aAddressFamily);
+    if (NS_SUCCEEDED(ttlRv)) {
+      (*aAddrInfo)->ttl = ttl;
+      LOG("Got TTL %u for %s (name = %s).", ttl, aHost, name);
+    } else {
+      LOG_WARNING("Could not get TTL for %s (cname = %s).", aHost, name);
+    }
+  }
+#endif
+
+  return rv;
+}
+
+} // namespace net
+} // namespace mozilla