Elep

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.verifyIntotoTLogBody = 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");
// Compare the given intoto tlog entry to the given bundle
function verifyIntotoTLogBody(tlogEntry, content) {
    switch (tlogEntry.apiVersion) {
        case '0.0.2':
            return verifyIntoto002TLogBody(tlogEntry, content);
        default:
            throw new error_1.VerificationError({
                code: 'TLOG_BODY_ERROR',
                message: `unsupported intoto version: ${tlogEntry.apiVersion}`,
            });
    }
}
exports.verifyIntotoTLogBody = verifyIntotoTLogBody;
// Compare the given intoto v0.0.2 tlog entry to the given DSSE envelope.
function verifyIntoto002TLogBody(tlogEntry, content) {
    // Ensure the bundle's DSSE contains a single signature
    if (tlogEntry.spec.content.envelope.signatures?.length !== 1) {
        throw new error_1.VerificationError({
            code: 'TLOG_BODY_ERROR',
            message: 'signature count mismatch',
        });
    }
    // Signature is double-base64-encoded in the tlog entry
    const tlogSig = base64Decode(tlogEntry.spec.content.envelope.signatures[0].sig);
    // Ensure that the signature in the bundle's DSSE matches tlog entry
    if (!content.compareSignature(Buffer.from(tlogSig, 'base64'))) {
        throw new error_1.VerificationError({
            code: 'TLOG_BODY_ERROR',
            message: 'tlog entry signature mismatch',
        });
    }
    // Ensure the digest of the bundle's DSSE payload matches the digest in the
    // tlog entry
    const tlogHash = tlogEntry.spec.content.payloadHash?.value || '';
    if (!content.compareDigest(Buffer.from(tlogHash, 'hex'))) {
        throw new error_1.VerificationError({
            code: 'TLOG_BODY_ERROR',
            message: 'DSSE payload hash mismatch',
        });
    }
}
function base64Decode(str) {
    return Buffer.from(str, 'base64').toString('utf-8');
}