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review.blissroms.org / platform_packages_modules_DnsResolver / e51091d19ac771c50034b499bb2f7cb1d0c91c26
commite51091d19ac771c50034b499bb2f7cb1d0c91c26[log] [tgz]
authorLorenzo Colitti <lorenzo@google.com>Wed May 20 02:48:44 2020 +0900
committerLorenzo Colitti <lorenzo@google.com>Thu May 21 18:02:07 2020 +0900
tree6d09b104bdde3c450750bfe2331b0cd885883701
parent468ac8ae145658bbe8a49fa64a9fad7c57708edb [diff]
Support DNS64 synthesis using externally-discovered prefixes.

Currently, the DNS resolver supports DNS64 synthesis only for
prefixes that it discovered itself, and not for NAT64 prefixes
discovered via other means (e.g., RA).

Add a way to set a NAT64 prefix that was discovered by other
means. This new IPC is mutually exclusive with the existing
prefix discovery mechansisms:

- Setting the prefix has no effect if prefix discovery is
  started.
- Starting (or stopping) prefix discovery clears the prefix.
- Setting the prefix does not result in any NAT64 prefix update
  callback.

It is the responsibility of the caller (ConnectivityService,
Nat464Xlat) to ensure that prefix discovery is stopped before
setting the prefix.

This does not add any significant complexity to the connectivity
code, and it ensures that the behaviour of the existing IPCs
(startPrefix64Discovery and stopPrefix64Discovery) are unchanged.
This is necessary to ensure that DNS64 synthesis continues to
work on Q devices.

Disallowing concurrent use of prefix discovery and externally-set
prefixes also simplifies the implementation because it allows
reuse of most of the data structures and teardown code in
Dns64Configuration. The externally-set prefix is represented by a
Dns64Configuration with a special discovery ID of kNoDiscoveryId
(== 0), which cannot be used by any discovery attempt. That way,
if discovery is started, then stopped, and then the prefix is
set, if a stale discovery thread then completes, it will be
ignored because the thread's ID cannot be kNoDiscoveryId.

Bug: 153694684
Bug: 156914456
Test: new tests in resolv_integration_test
Change-Id: I7c63fb62b70635a1b5cc7a21d60f091ba2705d72
9 files changed
tree: 6d09b104bdde3c450750bfe2331b0cd885883701
  1. aidl_api/
  2. apex/
  3. binder/
  4. include/
  5. tests/
  6. .clang-format ⇨ ../../../build/soong/scripts/system-clang-format
  7. .editorconfig
  8. Android.bp
  9. Dns64Configuration.cpp
  10. Dns64Configuration.h
  11. DnsProxyListener.cpp
  12. DnsProxyListener.h
  13. DnsQueryLog.cpp
  14. DnsQueryLog.h
  15. DnsQueryLogTest.cpp
  16. DnsResolver.cpp
  17. DnsResolver.h
  18. DnsResolverService.cpp
  19. DnsResolverService.h
  20. DnsStats.cpp
  21. DnsStats.h
  22. DnsStatsTest.cpp
  23. DnsTlsDispatcher.cpp
  24. DnsTlsDispatcher.h
  25. DnsTlsQueryMap.cpp
  26. DnsTlsQueryMap.h
  27. DnsTlsServer.cpp
  28. DnsTlsServer.h
  29. DnsTlsSessionCache.cpp
  30. DnsTlsSessionCache.h
  31. DnsTlsSocket.cpp
  32. DnsTlsSocket.h
  33. DnsTlsSocketFactory.h
  34. DnsTlsTransport.cpp
  35. DnsTlsTransport.h
  36. Experiments.cpp
  37. Experiments.h
  38. ExperimentsTest.cpp
  39. getaddrinfo.cpp
  40. getaddrinfo.h
  41. gethnamaddr.cpp
  42. gethnamaddr.h
  43. hostent.h
  44. IDnsTlsSocket.h
  45. IDnsTlsSocketFactory.h
  46. IDnsTlsSocketObserver.h
  47. libnetd_resolv.map.txt
  48. LockedQueue.h
  49. NOTICE
  50. OWNERS
  51. params.h
  52. PREUPLOAD.cfg
  53. PrivateDnsConfiguration.cpp
  54. PrivateDnsConfiguration.h
  55. README-DoT.md
  56. README.md
  57. res_cache.cpp
  58. res_comp.cpp
  59. res_comp.h
  60. res_debug.cpp
  61. res_debug.h
  62. res_init.cpp
  63. res_init.h
  64. res_mkquery.cpp
  65. res_query.cpp
  66. res_send.cpp
  67. res_send.h
  68. res_stats.cpp
  69. resolv_cache.h
  70. resolv_cache_unit_test.cpp
  71. resolv_callback_unit_test.cpp
  72. resolv_private.h
  73. resolv_test_config_template.xml
  74. resolv_tls_unit_test.cpp
  75. resolv_unit_test.cpp
  76. ResolverController.cpp
  77. ResolverController.h
  78. ResolverEventReporter.cpp
  79. ResolverEventReporter.h
  80. ResolverStats.h
  81. sethostent.cpp
  82. stats.h
  83. stats.proto
  84. TEST_MAPPING
  85. util.cpp
  86. util.h
README.md

Logging

This code uses LOG(X) for logging. Log levels are VERBOSE,DEBUG,INFO,WARNING and ERROR. The default setting is WARNING and logs relate to WARNING and ERROR will be shown. If you want to enable the DEBUG level logs, using following command. adb shell service call dnsresolver 10 i32 1 VERBOSE 0 DEBUG 1 INFO 2 WARNING 3 ERROR 4 Verbose resolver logs could contain PII -- do NOT enable in production builds.