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node_modules/@sigstore/sign/dist/witness/tsa/client.d.ts

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+/// <reference types="node" />
+import type { FetchOptions } from '../../types/fetch';
+export interface TSA {
+    createTimestamp: (signature: Buffer) => Promise<Buffer>;
+}
+export type TSAClientOptions = {
+    tsaBaseURL: string;
+} & FetchOptions;
+export declare class TSAClient implements TSA {
+    private tsa;
+    constructor(options: TSAClientOptions);
+    createTimestamp(signature: Buffer): Promise<Buffer>;
+}

node_modules/@sigstore/sign/dist/witness/tsa/client.js

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+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.TSAClient = void 0;
+/*
+Copyright 2023 The Sigstore Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+const error_1 = require("../../error");
+const tsa_1 = require("../../external/tsa");
+const util_1 = require("../../util");
+class TSAClient {
+    constructor(options) {
+        this.tsa = new tsa_1.TimestampAuthority({
+            baseURL: options.tsaBaseURL,
+            retry: options.retry,
+            timeout: options.timeout,
+        });
+    }
+    async createTimestamp(signature) {
+        const request = {
+            artifactHash: util_1.crypto.hash(signature).toString('base64'),
+            hashAlgorithm: 'sha256',
+        };
+        try {
+            return await this.tsa.createTimestamp(request);
+        }
+        catch (err) {
+            (0, error_1.internalError)(err, 'TSA_CREATE_TIMESTAMP_ERROR', 'error creating timestamp');
+        }
+    }
+}
+exports.TSAClient = TSAClient;

node_modules/@sigstore/sign/dist/witness/tsa/index.d.ts

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+import { TSAClientOptions } from './client';
+import type { RFC3161SignedTimestamp } from '@sigstore/bundle';
+import type { SignatureBundle, Witness } from '../witness';
+type RFC3161SignedTimestamps = {
+    rfc3161Timestamps: RFC3161SignedTimestamp[];
+};
+export type TSAWitnessOptions = TSAClientOptions;
+export declare class TSAWitness implements Witness {
+    private tsa;
+    constructor(options: TSAWitnessOptions);
+    testify(content: SignatureBundle): Promise<RFC3161SignedTimestamps>;
+}
+export {};

node_modules/@sigstore/sign/dist/witness/tsa/index.js

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+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.TSAWitness = void 0;
+/*
+Copyright 2023 The Sigstore Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+const client_1 = require("./client");
+class TSAWitness {
+    constructor(options) {
+        this.tsa = new client_1.TSAClient({
+            tsaBaseURL: options.tsaBaseURL,
+            retry: options.retry,
+            timeout: options.timeout,
+        });
+    }
+    async testify(content) {
+        const signature = extractSignature(content);
+        const timestamp = await this.tsa.createTimestamp(signature);
+        return {
+            rfc3161Timestamps: [{ signedTimestamp: timestamp }],
+        };
+    }
+}
+exports.TSAWitness = TSAWitness;
+function extractSignature(content) {
+    switch (content.$case) {
+        case 'dsseEnvelope':
+            return content.dsseEnvelope.signatures[0].sig;
+        case 'messageSignature':
+            return content.messageSignature.signature;
+    }
+}