João Lucas de Oliveira Lopes
3b46d43beb
* refactor: reorganize browser utility functions and improve buffer handling * fix: harden protobuf deserialization and clean up code * refactor: simplify data handling in GroupCipher and SenderKey classes * fix: Ensure consistent Buffer hydration and remove redundant code * refactor: update decodeAndHydrate calls to use proto types for improved type safety
35 lines
1013 B
TypeScript
35 lines
1013 B
TypeScript
import { calculateMAC } from 'libsignal/src/crypto'
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import { SenderMessageKey } from './sender-message-key'
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export class SenderChainKey {
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private readonly MESSAGE_KEY_SEED: Uint8Array = Buffer.from([0x01])
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private readonly CHAIN_KEY_SEED: Uint8Array = Buffer.from([0x02])
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private readonly iteration: number
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private readonly chainKey: Buffer
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constructor(iteration: number, chainKey: Uint8Array | Buffer) {
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this.iteration = iteration
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this.chainKey = Buffer.from(chainKey)
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}
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public getIteration(): number {
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return this.iteration
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}
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public getSenderMessageKey(): SenderMessageKey {
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return new SenderMessageKey(this.iteration, this.getDerivative(this.MESSAGE_KEY_SEED, this.chainKey))
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}
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public getNext(): SenderChainKey {
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return new SenderChainKey(this.iteration + 1, this.getDerivative(this.CHAIN_KEY_SEED, this.chainKey))
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}
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public getSeed(): Uint8Array {
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return this.chainKey
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}
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private getDerivative(seed: Uint8Array, key: Buffer): Uint8Array {
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return calculateMAC(key, seed)
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}
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}
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