packages/docs-core/lib/UseCase/DecryptMessage.ts

   1 import type { Event } from '@proton/docs-proto'
   2 import { DocumentUpdate } from '@proton/docs-proto'
   3 import type { EncryptionService } from '../Services/Encryption/EncryptionService'
   4 import { GetAssociatedEncryptionDataForRealtimeMessage } from './GetAdditionalEncryptionData'
   5 import type { EncryptionContext } from '../Services/Encryption/EncryptionContext'
   6 import type { SessionKey } from '@proton/crypto'
   7 import { VERIFICATION_STATUS } from '@proton/crypto'
   8 import { DecryptedMessage } from '@proton/docs-shared'
   9 import type { UseCaseInterface } from '../Domain/UseCase/UseCaseInterface'
  10 import { Result } from '@proton/docs-shared'
  11
  12 export type DecryptMessageDTO = {
  13   message: DocumentUpdate | Event
  14   documentContentKey: SessionKey
  15   verify: boolean
  16 }
  17
  18 export class DecryptMessage implements UseCaseInterface<DecryptedMessage> {
  19   constructor(private encryption: EncryptionService<EncryptionContext.RealtimeMessage>) {}
  20
  21   async execute(dto: DecryptMessageDTO): Promise<Result<DecryptedMessage>> {
  22     const decrypted = await this.encryption.decryptData(
  23       dto.message instanceof DocumentUpdate ? dto.message.encryptedContent : dto.message.content,
  24       GetAssociatedEncryptionDataForRealtimeMessage(dto.message),
  25       dto.documentContentKey,
  26     )
  27
  28     if (decrypted.isFailed()) {
  29       return Result.fail(decrypted.getError())
  30     }
  31
  32     if (dto.verify) {
  33       const verificationKey = await this.encryption.getVerificationKey(dto.message.authorAddress)
  34
  35       if (verificationKey.isFailed()) {
  36         return Result.fail(verificationKey.getError())
  37       }
  38
  39       const verifyResult = await this.encryption.verifyData(
  40         decrypted.getValue().content,
  41         decrypted.getValue().signature,
  42         GetAssociatedEncryptionDataForRealtimeMessage(dto.message),
  43         verificationKey.getValue(),
  44       )
  45
  46       if (verifyResult.isFailed()) {
  47         return Result.fail(verifyResult.getError())
  48       }
  49
  50       if (verifyResult.getValue() !== VERIFICATION_STATUS.SIGNED_AND_VALID) {
  51         return Result.fail(`Message content verification failed: ${verifyResult.getValue()}`)
  52       }
  53     }
  54
  55     const message = new DecryptedMessage({
  56       content: decrypted.getValue().content,
  57       signature: decrypted.getValue().signature,
  58       aad: GetAssociatedEncryptionDataForRealtimeMessage(dto.message),
  59       authorAddress: dto.message.authorAddress,
  60       timestamp: dto.message.timestamp,
  61     })
  62
  63     return Result.ok(message)
  64   }
  65 }