Flutterアプリの難読化とエラーレポート(iOS)

"Flutter Meetup Tokyo #6"で使った資料です。
https://flutter-jp.connpass.com/event/105834/

Transcript

1. FlutterΞϓϦͷ೉ಡԽͱ
   ΤϥʔϨϙʔτ(iOS)
   Hiroki Matsue
   Dec 6th, 2018
   Flutter Meetup Tokyo #6
   

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2. Hiroki Matsue (@macs_6)
   

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3. FlutterͰIIJmio޲͚ʹ
   ʮΈ͓εΠονʯΛ
   ϦϦʔε
   

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5. [࣭໰] FlutterͰΞϓϦΛ
   ϦϦʔε͍ͯ͠Δਓʁ
   

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6. [࣭໰] ϦϦʔεલʹ
   ೉ಡԽͨ͠ਓʁ
   

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7. ϦϦʔεؔ࿈ͷυΩϡϝϯτ
   https://flutter.io/docs/deployment/ios
   

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10. ࠷ॳʹॻ͍͚ͯ͋ͬͨͲ
    ݟམͱͯͨ͠
    (AndroidͷProGuardରԠͯͯ͠ؾ͍ͮͨ)
    

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11. ͪͳΈʹ
    

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12. (ϦϦʔεؔ࿈Ͱ୤ઢ)
    ΞΠίϯ࡞੒͸"flutterlaunchericons"࢖͏ͱ
    1ͭͷը૾͔Β͍͍ײ͡ʹ࡞ͬͯ͘ΕΔ
    

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13. iOS͸Dartίʔυ෦෼͕
    ೉ಡԽͷର৅
    

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14. ΍Δ͜ͱ͸build࣌ʹ
    ΦϓγϣϯΛ͚ͭΔ͚ͩ
    (Կނ͔ॳظঢ়ଶͰ͸ରԠ͞Εͯͳ͍ )
    https://github.com/flutter/flutter/wiki/Obfuscating-Dart-Code
    

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15. /ios/Flutter/Release.xcconfig
    EXTRA_GEN_SNAPSHOT_OPTIONS=--obfuscate
    

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16. # /packages/flutter_tools/bin/xcode_backend.sh
    local extra_gen_snapshot_options_or_none=""
    if [[ -n "$EXTRA_GEN_SNAPSHOT_OPTIONS" ]]; then
    extra_gen_snapshot_options_or_none="--extra-gen-snapshot-options=$EXTRA_GEN_SNAPSHOT_OPTIONS"
    fi
    ...
    RunCommand "${FLUTTER_ROOT}/bin/flutter" --suppress-analytics \
    ${verbose_flag} \
    build aot \
    --output-dir="${build_dir}/aot" \
    --target-platform=ios \
    --target="${target_path}" \
    --${build_mode} \
    --ios-arch="${archs}" \
    ${local_engine_flag} \
    ${track_widget_creation_flag} \
    ${extra_gen_snapshot_options_or_none}
    

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17. # /packages/flutter_tools/bin/xcode_backend.sh
    local extra_gen_snapshot_options_or_none=""
    if [[ -n "$EXTRA_GEN_SNAPSHOT_OPTIONS" ]]; then
    extra_gen_snapshot_options_or_none="--extra-gen-snapshot-options=$EXTRA_GEN_SNAPSHOT_OPTIONS"
    fi
    ...
    RunCommand "${FLUTTER_ROOT}/bin/flutter" --suppress-analytics \
    ${verbose_flag} \
    build aot \
    --output-dir="${build_dir}/aot" \
    --target-platform=ios \
    --target="${target_path}" \
    --${build_mode} \
    --ios-arch="${archs}" \
    ${local_engine_flag} \
    ${track_widget_creation_flag} \
    ${extra_gen_snapshot_options_or_none}
    

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18. xcode_backend.sh ͱ͸ʁ
    Build PhaseͷRun ScriptͰ࢖ΘΕ͍ͯΔεΫϦϓτ
    Xcode͔Β΋Dartίʔυ͕build͞ΕΔͷ͸͜Εͷ͓͔͛
    

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19. (୤ઢ2)
    طଘΞϓϦʹFlutterΛಋೖ͢Δ࣌͸
    xcode_backend.sh embed
    Add2AppϘʔυ্Ͱઈࢍ։ൃத
    

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20. ͜ΕͰϏϧυ͢Ε͹
    ೉ಡԽ׬ྃʂ
    Χϯλϯʂ
    

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21. ೉ಡԽͷ֬ೝํ๏ʁ
    

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22. App.frameworkΛ֬ೝ͢Δ
    $ strings build/ios/Release-iphoneos/Runner.app/Frameworks/App.framework/App
    ...
    get:_vxa@7048458x
    get:_aLa@9040228x
    get:_DLa@7048458x
    ...
    

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23. ೉ಡԽͷલޙͰൺֱ
    before
    get:_count@7048458
    get:_onData@9040228
    get:_isSubscribed@7048458
    after
    get:_vxa@7048458x
    get:_aLa@9040228x
    get:_DLa@7048458x
    

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24. Dartίʔυ͕೉ಡԽ͞Εͨ
    

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25. ...ϦϦʔεޙͷ͋Δ೔
    

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27. SentryͷΤϥʔϨϙʔτ΋
    ೉ಡԽ͞ΕͯΔ
    

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28. ೉ಡԽલͷΤϥʔϨϙʔτ
    

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29. ։ൃத͸ؾ͔ͮͳ͔ͬͨ
    

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30. ೉ಡԽͷલޙͰൺֱ
    before
    main.dart in SampleApp.build at line 48
    after
    SEd in bZ.opa at line 48
    

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31. ࣗ෼΋ಡΊͳ͍
    

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32. ϦϦʔεࡁΞϓϦͷ
    Τϥʔ΋ݟ͍ͨ
    

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33. mapϑΝΠϧΛग़ྗ͢Δ
    ઌ΄ͲͷυΩϡϝϯτʹ͋ͬͨઃఆ
    EXTRA_GEN_SNAPSHOT_OPTIONS=--obfuscate
    mapϑΝΠϧΛग़ྗ͢ΔઃఆΛ௥Ճ
    EXTRA_GEN_SNAPSHOT_OPTIONS=--obfuscate,
    ɹ --save-obfuscation-map=ios_dart_symbols_${FLUTTER_BUILD_NUMBER}.json
    

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34. ग़ྗ͞ΕͨmapϑΝΠϧ
    $ cat ios_dart_symbols_5.json
    ...
    "_BuildJsonListener","_Gf",
    "CustomSymbolRenderer","cs",
    "devicePixelRatio","saa"
    ...
    ͜ΕΛࢀর͢Ε͹ಡΊΔ
    !
    

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35. աڈʹϦϦʔεͨ͠ΞϓϦͷmapϑΝΠϧʁ
    ࢼͨ͠ͱ͜Ζɺ
    ੜ੒ݩͷίʔυ͕ಉ͡Ͱ͋Ε͹map΋ಉ͡ʹͳͬͨ
    

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36. ·ͱΊ
    

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37. ·ͱΊ
    • FlutterͩͱiOSͰ΋Dartίʔυͷ೉ಡԽ࡞ۀ͕͋Δ
    • stringsίϚϯυͰνΣοΫ͢Δͷָ͕
    • mapϑΝΠϧ΋ग़ྗ͓ͯ͘͠ͱSentryղಡʹ࢖͑Δ
    # before
    main.dart in SampleApp.build at line 48
    # after
    SEd in bZ.opa at line 48
    

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38. Έ͓εΠονɺੋඇ͝ར༻͍ͩ͘͞
    

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39. Thanks
    

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