😮 Recent changes to post-login initialization ? #106

clins1994 · 2026-04-07T08:20:07Z

clins1994
Apr 7, 2026

On a recent network traffic analysis I found that post-login initialization step used TalkService/getE2EEPublicKeysEx on the line chrome extension but we use a combination of getE2EEPublicKey and negotiateE2EEPublicKey.

Questions

Should we change it to use TalkService/getE2EEPublicKeysEx ?
Should we upgrade LINE Chrome Extension to 3.7.2 instead of 3.7.1 ?

Post-Login Initialization

Method	Status	Bridge Status
`TalkService/getProfile`	200	Implemented
`TalkService/getEncryptedIdentityV3`	200	Implemented
`TalkService/getServerTime`	200	Not implemented (not critical)
`TalkService/getLastOpRevision`	200	Implemented
`TalkService/getConfigurations`	200	Not implemented
`TalkService/getSettings`	200	Not implemented
`TalkService/getE2EEPublicKeysEx`	200	Not implemented (we use `getE2EEPublicKey` and `negotiateE2EEPublicKey`)

To be discussed ... Below is the complete traffic analysis for reference

Traffic Analysis

Login Flow (in order)

Method	Status	Bridge Equivalent
`SecondaryQrCodeLoginService/createSession`	200	`pkg/line/client.go` — implemented
`SecondaryQrCodeLoginService/createQrCode`	200	`pkg/line/client.go` — implemented
`SecondaryQrCodeLoginPermitNoticeService/checkQrCodeVerified`	—	`pkg/line/client.go` — implemented
`TalkService/getRSAKeyInfo`	200	`pkg/line/client.go` — implemented
`AuthService/loginV2`	200	`pkg/line/methods.go` — implemented
`AuthService/logoutV2`	200	Not implemented (we don't log out)

Post-Login Initialization

Method	Status	Bridge Status
`TalkService/getProfile`	200	Implemented
`TalkService/getEncryptedIdentityV3`	200	Implemented
`TalkService/getServerTime`	200	Not implemented (not critical)
`TalkService/getLastOpRevision`	200	Implemented
`TalkService/getConfigurations`	200	Not implemented
`TalkService/getSettings`	200	Not implemented
`TalkService/getE2EEPublicKeysEx`	200	Not implemented (we use `getE2EEPublicKey` and `negotiateE2EEPublicKey`)

Contact & Chat Discovery — the key finding

Method	Status	Bridge Status
`TalkService/getAllContactIds`	200	NOT IMPLEMENTED — returns all friend MIDs
`TalkService/getAllChatMids`	200	Implemented
`TalkService/getMessageBoxes`	200	Implemented
`TalkService/getContactsV2`	200	Implemented (but needs the MIDs from above)
`TalkService/getChats`	200	Implemented

E2EE

Method	Status	Bridge Status
`TalkService/getE2EEGroupSharedKey`	200	Implemented
`TalkService/getLastE2EEPublicKeys`	200	Not implemented (we use per-peer negotiation)

Other Services

Method	Status	Bridge Status
`BuddyService/getBuddyDetail`	400	Not implemented — official accounts/bots detail
`ShopService/getOwnedProductSummaries`	200	Not implemented — sticker packs (not needed)
Long-poll SSE `/api/operation/receive`	200	Implemented in `pkg/line/sse.go`
`/api/lan/notice`	200	Not implemented — LINE notifications/announcements

clins1994 · 2026-04-08T13:11:16Z

clins1994
Apr 8, 2026
Author

CDP Capture Follow-up (2026-04-08)

Ran a second capture using the CDP-based script (scripts/line-cdp-capture.py) which captures full request/response JSON bodies — unlike the net-log capture which only gets connection-level metadata.

Key finding: `getE2EEPublicKeysEx` was NOT called this session

The Chrome Extension (v3.7.2) did not call getE2EEPublicKeysEx during this session's startup. Instead it used:

getLastE2EEPublicKeys — a bulk fetch that takes a single token string and returns a map of MID → E2EEPublicKey for recently-updated keys:
- Request: ["<session/cache token>"]
- Response: {"code":0, "data": {"<mid1>": {"version":1, "keyId":..., "keyData":"...", "createdTime":"..."}, "<mid2>": {...}, ...}}
Individual getE2EEPublicKey calls (9 of them) for specific contacts — same as what the bridge already uses.

This suggests getE2EEPublicKeysEx may only be called on first login or when the local key cache is completely cold. getLastE2EEPublicKeys appears to be the steady-state bulk key sync method.

Also confirmed: `getAllContactIds`

Full request/response captured:

Request: [2]
Response: returns all friend MIDs (1000+ contacts in one call)

This is the missing piece for proper contacts sync — much better than getMessageBoxes which caps at 100 recent conversations.

Next steps

Implement getAllContactIds (trivial — single arg [2], returns MID list)
Implement getLastE2EEPublicKeys (bulk key fetch, returns MID→key map)
Consider another capture with cleared extension storage to trigger getE2EEPublicKeysEx and understand its cold-start role

0 replies

clins1994 · 2026-04-08T13:16:39Z

clins1994
Apr 8, 2026
Author

There seems to be a difference between cold starts and subsequent logins for the bulk encryption key fetcher

cc @highesttt working on supporting this at the moment, seems like the number one priority. let me know if you are working on it already

Continuing ... Testing a fresh cold start run and getting the payloads. Will post here as I find stuff

0 replies

clins1994 · 2026-04-08T13:24:06Z

clins1994
Apr 8, 2026
Author

Current hypothesis

getE2EEPublicKeysEx only appears for the LSOFF user on first login after April 1st ... It was the first login on the LINE Chrome Extension after April 1st
getE2EEPublicKeyEx is never used users who were already LSON users before April 1st

Doing a login with the former LSOFF to see if it still calls it

0 replies

clins1994 · 2026-04-08T13:29:19Z

clins1994
Apr 8, 2026
Author

LSOFF Login Report

4 digit PIN Code appeared, strange. And no E2EE related calls after logging in ... Super confusing. Did they revert the Letter Sealing for everyone feature? 🫠

No getE2EEPublicKeysEx. And notably — zero E2EE key calls at all. No getE2EEPublicKey, no getLastE2EEPublicKeys, no negotiateE2EEPublicKey. This LSOFF user doesn't do any E2EE key fetching because letter sealing is off — messages aren't encrypted.

So your hypothesis is looking strong: getE2EEPublicKeysEx was likely called during the first login after April 1st when the LSOFF user was migrated to LSON — a one-time key bootstrapping call to fetch public keys for all contacts at once during the migration.

For the bridge this means:
  - getE2EEPublicKeysEx — one-time migration, not needed for steady-state (assumption)
  - getLastE2EEPublicKeys — bulk key delta sync, used by LSON users on every session
  - getAllContactIds — full friend list, used by both LSON and LSOFF users

Checking news ... :x EDIT: no news found

1 reply

clins1994 Apr 8, 2026
Author

`getSettings` response from LSOFF user (2026-04-08)

Note e2eeEnable: false — this account still has letter sealing disabled. No E2EE key calls were made during this session. No "Letter Sealing" toggle button appears in settings ... 🤷‍♂️ I'll revisit this after a while

{
  "code": 0,
  "message": "OK",
  "data": {
    "notificationEnable": true,
    "notificationMuteExpiration": "-1",
    "notificationNewMessage": true,
    "notificationGroupInvitation": true,
    "notificationShowMessage": true,
    "notificationIncomingCall": true,
    "notificationDisabledWithSub": true,
    "notificationPayment": true,
    "notificationMention": true,
    "notificationThumbnail": true,
    "notificationBadgeTalkOnly": false,
    "notificationReaction": true,
    "notificationShowProfileImage": true,
    "privacySyncContacts": false,
    "privacySearchByPhoneNumber": false,
    "privacySearchByUserid": true,
    "privacySearchByEmail": false,
    "privacyAllowSecondaryDeviceLogin": true,
    "privacyProfileImagePostToMyhome": false,
    "privacyProfileMusicPostToMyhome": false,
    "privacyReceiveMessagesFromNotFriend": true,
    "privacyAgreeUseLineCoinToPaidCall": false,
    "privacyAgreeUsePaidCall": false,
    "privacyAllowFriendRequest": true,
    "privacyAllowNearby": false,
    "privacySharePersonalInfoToFriends": 1,
    "privacyAgeResult": 1,
    "privacyAgeResultReceived": true,
    "privacyAllowFollow": true,
    "privacyShowFollowList": false,
    "contactMyTicket": "<redacted>",
    "identityProvider": 1,
    "identityIdentifier": "<redacted>",
    "snsAccounts": {},
    "phoneRegistration": true,
    "emailConfirmationStatus": 3,
    "accountMigrationPincodeType": 0,
    "enforcedInputAccountMigrationPincode": false,
    "securityCenterSettingsType": 0,
    "allowUnregistrationSecondaryDevice": false,
    "pwlessPrimaryCredentialRegistration": false,
    "preferenceLocale": "ja",
    "customModes": {},
    "e2eeEnable": false,
    "hitokotoBackupRequested": false,
    "agreementNearbyTime": "-1",
    "agreementSquareTime": "<redacted>",
    "botUseAgreementAcceptedAt": "<redacted>",
    "agreementShakeFunction": "-1",
    "agreementMobileContactName": "0",
    "agreementSoundToText": "0",
    "privacyPolicyVersion": "13.0.0",
    "agreementAdByWebAccess": "<redacted>",
    "agreementPhoneNumberMatching": "<redacted>",
    "agreementCommunicationInfo": "<redacted>",
    "agreementThingsWirelessCommunication": "0",
    "agreementGdpr": "-2",
    "agreementProvideLocation": "<redacted>",
    "agreementBeacon": "<redacted>",
    "agreementContentsSuggest": "-1",
    "agreementContentsSuggestDataCollection": "-1",
    "agreementOcrImageCollection": "-1",
    "agreementIcna": "-2",
    "agreementMid": "<redacted>",
    "agreementPdp": "-2",
    "agreementPdpa": "-2",
    "agreementLocationVersion": "1.0.0",
    "agreementSnowAiAvatar": "0",
    "agreementAlbumUsageData": "<redacted>",
    "agreementAlbumUsageDataVersion": "1",
    "agreementLypPremiumAlbum": "<redacted>",
    "agreementLypPremiumAlbumVersion": "1",
    "agreementLypPremiumBackup": "<redacted>",
    "agreementLypPremiumBackupVersion": "1",
    "agreementPremiumBackupPremiumType": "LYP_PREMIUM",
    "agreementOaAiAssistant": "0",
    "agreementOaAiAssistantVersion": "1",
    "agreementLypPremiumMultiProfile": "0",
    "agreementLypPremiumMultiProfileVersion": "0",
    "agreementLineOutUse": "0",
    "agreementLineOutProvideInfo": "0",
    "homeNotificationNewFriend": true,
    "homeNotificationFavoriteFriendUpdate": true,
    "homeNotificationGroupMemberUpdate": true,
    "homeNotificationBirthday": true,
    "homeNotificationNoteNoteLike": true,
    "homeNotificationNoteComment": true,
    "homeNotificationNoteCommentLike": true,
    "homeNotificationNoteMention": true,
    "eapAllowedToConnect": {
      "1": false,
      "6": false
    },
    "zhdPageAllowedToShow": false,
    "eapOnlyAccountTargetCountry": false,
    "agreementPremiumAlbumPremiumType": ""
  }
}

clins1994 · 2026-04-09T15:41:34Z

clins1994
Apr 9, 2026
Author

Closing this to make a more organized discussion for educational purposes

0 replies

😮 Recent changes to post-login initialization ? #106

Uh oh!

Uh oh!

clins1994 Apr 7, 2026

Post-Login Initialization

Traffic Analysis

Login Flow (in order)

Post-Login Initialization

Contact & Chat Discovery — the key finding

E2EE

Other Services

Replies: 5 comments · 1 reply

Uh oh!

clins1994 Apr 8, 2026 Author

CDP Capture Follow-up (2026-04-08)

Key finding: getE2EEPublicKeysEx was NOT called this session

Also confirmed: getAllContactIds

Next steps

Uh oh!

Uh oh!

clins1994 Apr 8, 2026 Author

Uh oh!

Uh oh!

clins1994 Apr 8, 2026 Author

Uh oh!

Uh oh!

clins1994 Apr 8, 2026 Author

LSOFF Login Report

Uh oh!

Uh oh!

clins1994 Apr 8, 2026 Author

getSettings response from LSOFF user (2026-04-08)

Uh oh!

clins1994 Apr 9, 2026 Author

clins1994
Apr 7, 2026

Replies: 5 comments 1 reply

clins1994
Apr 8, 2026
Author

Key finding: `getE2EEPublicKeysEx` was NOT called this session

Also confirmed: `getAllContactIds`

clins1994
Apr 8, 2026
Author

clins1994
Apr 8, 2026
Author

clins1994
Apr 8, 2026
Author

clins1994 Apr 8, 2026
Author

`getSettings` response from LSOFF user (2026-04-08)

clins1994
Apr 9, 2026
Author