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"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.TrustedMetadataStore = void 0;
const error_1 = require("./error");
const models_1 = require("./models");
const types_1 = require("./utils/types");
class TrustedMetadataStore {
constructor(rootData) {
this.trustedSet = {};
// Client workflow 5.1: record fixed update start time
this.referenceTime = new Date();
// Client workflow 5.2: load trusted root metadata
this.loadTrustedRoot(rootData);
}
get root() {
if (!this.trustedSet.root) {
throw new ReferenceError('No trusted root metadata');
}
return this.trustedSet.root;
}
get timestamp() {
return this.trustedSet.timestamp;
}
get snapshot() {
return this.trustedSet.snapshot;
}
get targets() {
return this.trustedSet.targets;
}
getRole(name) {
return this.trustedSet[name];
}
updateRoot(bytesBuffer) {
const data = JSON.parse(bytesBuffer.toString('utf8'));
const newRoot = models_1.Metadata.fromJSON(types_1.MetadataKind.Root, data);
if (newRoot.signed.type != types_1.MetadataKind.Root) {
throw new error_1.RepositoryError(`Expected 'root', got ${newRoot.signed.type}`);
}
// Client workflow 5.4: check for arbitrary software attack
this.root.verifyDelegate(types_1.MetadataKind.Root, newRoot);
// Client workflow 5.5: check for rollback attack
if (newRoot.signed.version != this.root.signed.version + 1) {
throw new error_1.BadVersionError(`Expected version ${this.root.signed.version + 1}, got ${newRoot.signed.version}`);
}
// Check that new root is signed by self
newRoot.verifyDelegate(types_1.MetadataKind.Root, newRoot);
// Client workflow 5.7: set new root as trusted root
this.trustedSet.root = newRoot;
return newRoot;
}
updateTimestamp(bytesBuffer) {
if (this.snapshot) {
throw new error_1.RuntimeError('Cannot update timestamp after snapshot');
}
if (this.root.signed.isExpired(this.referenceTime)) {
throw new error_1.ExpiredMetadataError('Final root.json is expired');
}
const data = JSON.parse(bytesBuffer.toString('utf8'));
const newTimestamp = models_1.Metadata.fromJSON(types_1.MetadataKind.Timestamp, data);
if (newTimestamp.signed.type != types_1.MetadataKind.Timestamp) {
throw new error_1.RepositoryError(`Expected 'timestamp', got ${newTimestamp.signed.type}`);
}
// Client workflow 5.4.2: check for arbitrary software attack
this.root.verifyDelegate(types_1.MetadataKind.Timestamp, newTimestamp);
if (this.timestamp) {
// Prevent rolling back timestamp version
// Client workflow 5.4.3.1: check for rollback attack
if (newTimestamp.signed.version < this.timestamp.signed.version) {
throw new error_1.BadVersionError(`New timestamp version ${newTimestamp.signed.version} is less than current version ${this.timestamp.signed.version}`);
}
// Keep using old timestamp if versions are equal.
if (newTimestamp.signed.version === this.timestamp.signed.version) {
throw new error_1.EqualVersionError(`New timestamp version ${newTimestamp.signed.version} is equal to current version ${this.timestamp.signed.version}`);
}
// Prevent rolling back snapshot version
// Client workflow 5.4.3.2: check for rollback attack
const snapshotMeta = this.timestamp.signed.snapshotMeta;
const newSnapshotMeta = newTimestamp.signed.snapshotMeta;
if (newSnapshotMeta.version < snapshotMeta.version) {
throw new error_1.BadVersionError(`New snapshot version ${newSnapshotMeta.version} is less than current version ${snapshotMeta.version}`);
}
}
// expiry not checked to allow old timestamp to be used for rollback
// protection of new timestamp: expiry is checked in update_snapshot
this.trustedSet.timestamp = newTimestamp;
// Client workflow 5.4.4: check for freeze attack
this.checkFinalTimestamp();
return newTimestamp;
}
updateSnapshot(bytesBuffer, trusted = false) {
if (!this.timestamp) {
throw new error_1.RuntimeError('Cannot update snapshot before timestamp');
}
if (this.targets) {
throw new error_1.RuntimeError('Cannot update snapshot after targets');
}
// Snapshot cannot be loaded if final timestamp is expired
this.checkFinalTimestamp();
const snapshotMeta = this.timestamp.signed.snapshotMeta;
// Verify non-trusted data against the hashes in timestamp, if any.
// Trusted snapshot data has already been verified once.
// Client workflow 5.5.2: check against timestamp role's snaphsot hash
if (!trusted) {
snapshotMeta.verify(bytesBuffer);
}
const data = JSON.parse(bytesBuffer.toString('utf8'));
const newSnapshot = models_1.Metadata.fromJSON(types_1.MetadataKind.Snapshot, data);
if (newSnapshot.signed.type != types_1.MetadataKind.Snapshot) {
throw new error_1.RepositoryError(`Expected 'snapshot', got ${newSnapshot.signed.type}`);
}
// Client workflow 5.5.3: check for arbitrary software attack
this.root.verifyDelegate(types_1.MetadataKind.Snapshot, newSnapshot);
// version check against meta version (5.5.4) is deferred to allow old
// snapshot to be used in rollback protection
// Client workflow 5.5.5: check for rollback attack
if (this.snapshot) {
Object.entries(this.snapshot.signed.meta).forEach(([fileName, fileInfo]) => {
const newFileInfo = newSnapshot.signed.meta[fileName];
if (!newFileInfo) {
throw new error_1.RepositoryError(`Missing file ${fileName} in new snapshot`);
}
if (newFileInfo.version < fileInfo.version) {
throw new error_1.BadVersionError(`New version ${newFileInfo.version} of ${fileName} is less than current version ${fileInfo.version}`);
}
});
}
this.trustedSet.snapshot = newSnapshot;
// snapshot is loaded, but we raise if it's not valid _final_ snapshot
// Client workflow 5.5.4 & 5.5.6
this.checkFinalSnapsnot();
return newSnapshot;
}
updateDelegatedTargets(bytesBuffer, roleName, delegatorName) {
if (!this.snapshot) {
throw new error_1.RuntimeError('Cannot update delegated targets before snapshot');
}
// Targets cannot be loaded if final snapshot is expired or its version
// does not match meta version in timestamp.
this.checkFinalSnapsnot();
const delegator = this.trustedSet[delegatorName];
if (!delegator) {
throw new error_1.RuntimeError(`No trusted ${delegatorName} metadata`);
}
// Extract metadata for the delegated role from snapshot
const meta = this.snapshot.signed.meta?.[`${roleName}.json`];
if (!meta) {
throw new error_1.RepositoryError(`Missing ${roleName}.json in snapshot`);
}
// Client workflow 5.6.2: check against snapshot role's targets hash
meta.verify(bytesBuffer);
const data = JSON.parse(bytesBuffer.toString('utf8'));
const newDelegate = models_1.Metadata.fromJSON(types_1.MetadataKind.Targets, data);
if (newDelegate.signed.type != types_1.MetadataKind.Targets) {
throw new error_1.RepositoryError(`Expected 'targets', got ${newDelegate.signed.type}`);
}
// Client workflow 5.6.3: check for arbitrary software attack
delegator.verifyDelegate(roleName, newDelegate);
// Client workflow 5.6.4: Check against snapshot role’s targets version
const version = newDelegate.signed.version;
if (version != meta.version) {
throw new error_1.BadVersionError(`Version ${version} of ${roleName} does not match snapshot version ${meta.version}`);
}
// Client workflow 5.6.5: check for a freeze attack
if (newDelegate.signed.isExpired(this.referenceTime)) {
throw new error_1.ExpiredMetadataError(`${roleName}.json is expired`);
}
this.trustedSet[roleName] = newDelegate;
}
// Verifies and loads data as trusted root metadata.
// Note that an expired initial root is still considered valid.
loadTrustedRoot(bytesBuffer) {
const data = JSON.parse(bytesBuffer.toString('utf8'));
const root = models_1.Metadata.fromJSON(types_1.MetadataKind.Root, data);
if (root.signed.type != types_1.MetadataKind.Root) {
throw new error_1.RepositoryError(`Expected 'root', got ${root.signed.type}`);
}
root.verifyDelegate(types_1.MetadataKind.Root, root);
this.trustedSet['root'] = root;
}
checkFinalTimestamp() {
// Timestamp MUST be loaded
if (!this.timestamp) {
throw new ReferenceError('No trusted timestamp metadata');
}
// Client workflow 5.4.4: check for freeze attack
if (this.timestamp.signed.isExpired(this.referenceTime)) {
throw new error_1.ExpiredMetadataError('Final timestamp.json is expired');
}
}
checkFinalSnapsnot() {
// Snapshot and timestamp MUST be loaded
if (!this.snapshot) {
throw new ReferenceError('No trusted snapshot metadata');
}
if (!this.timestamp) {
throw new ReferenceError('No trusted timestamp metadata');
}
// Client workflow 5.5.6: check for freeze attack
if (this.snapshot.signed.isExpired(this.referenceTime)) {
throw new error_1.ExpiredMetadataError('snapshot.json is expired');
}
// Client workflow 5.5.4: check against timestamp role’s snapshot version
const snapshotMeta = this.timestamp.signed.snapshotMeta;
if (this.snapshot.signed.version !== snapshotMeta.version) {
throw new error_1.BadVersionError("Snapshot version doesn't match timestamp");
}
}
}
exports.TrustedMetadataStore = TrustedMetadataStore;
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