src/crypto/encoding.ts - master - raiden/obsidian-git-encrypt

src/crypto/encoding.ts
78 строк2 KB
Robert Kuzhin
feat: add encrypted mirror and manifest store
09 авг 2026, 10:06
09 авг 2026, 10:067f1b7fe
import { FORMAT_VERSION } from "./constants.js";

const encoder = new TextEncoder();
const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/u;

export function encodeUtf8(value: string): Uint8Array {
  return encoder.encode(value);
}

export function concatBytes(...parts: readonly Uint8Array[]): Uint8Array {
  const length = parts.reduce((total, part) => total + part.length, 0);
  const result = new Uint8Array(length);
  let offset = 0;
  for (const part of parts) {
    result.set(part, offset);
    offset += part.length;
  }
  return result;
}

function encodeField(value: string): Uint8Array {
  const bytes = encodeUtf8(value);
  if (bytes.length > 0xffff) {
    throw new RangeError("Authenticated context field is too long");
  }

  const result = new Uint8Array(2 + bytes.length);
  new DataView(result.buffer).setUint16(0, bytes.length, false);
  result.set(bytes, 2);
  return result;
}

export function buildAssociatedData(
  vaultId: string,
  objectType: "file" | "manifest" | "vault-key",
  fileId: string,
): Uint8Array {
  assertUuid(vaultId, "vaultId");
  if (objectType === "file") {
    assertUuid(fileId, "fileId");
  } else if (fileId !== objectType) {
    throw new TypeError(`${objectType} payload must use its canonical identity`);
  }

  return concatBytes(
    new Uint8Array([FORMAT_VERSION]),
    encodeField(vaultId),
    encodeField(objectType),
    encodeField(fileId),
  );
}

export function buildObjectKeyInfo(fileId: string): Uint8Array {
  assertUuid(fileId, "fileId");
  return concatBytes(encodeField("obsidian-encrypted-git/file-key/v1"), encodeField(fileId));
}

export function buildManifestKeyInfo(): Uint8Array {
  return encodeField("obsidian-encrypted-git/manifest-key/v1");
}

export function assertUuid(value: string, fieldName: string): void {
  if (!UUID_PATTERN.test(value)) {
    throw new TypeError(`${fieldName} must be a lowercase UUIDv4`);
  }
}

export function randomUuid(random: Uint8Array): string {
  if (random.length !== 16) {
    throw new RangeError("UUID input must contain 16 bytes");
  }

  const bytes = new Uint8Array(random);
  bytes[6] = (bytes[6]! & 0x0f) | 0x40;
  bytes[8] = (bytes[8]! & 0x3f) | 0x80;
  const hex = [...bytes].map((value) => value.toString(16).padStart(2, "0")).join("");
  return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`;
}