mirror of
https://github.com/Ylianst/MeshCentral.git
synced 2025-01-13 07:53:20 -05:00
393 lines
20 KiB
JavaScript
393 lines
20 KiB
JavaScript
/**
|
|
* @description Authenticode parsing
|
|
* @author Bryan Roe & Ylian Saint-Hilaire
|
|
* @copyright Intel Corporation 2018-2022
|
|
* @license Apache-2.0
|
|
* @version v0.0.1
|
|
*/
|
|
|
|
function createAuthenticodeHandler(path) {
|
|
const obj = {};
|
|
const fs = require('fs');
|
|
const crypto = require('crypto');
|
|
const forge = require('node-forge');
|
|
const pki = forge.pki;
|
|
const p7 = require('./pkcs7-modified');
|
|
obj.header = { path: path }
|
|
|
|
// Read a file slice
|
|
function readFileSlice(start, length) {
|
|
var buffer = Buffer.alloc(length);
|
|
var len = fs.readSync(obj.fd, buffer, 0, buffer.length, start);
|
|
if (len < buffer.length) { buffer = buffer.slice(0, len); }
|
|
return buffer;
|
|
}
|
|
|
|
// Close the file
|
|
obj.close = function () {
|
|
if (obj.fd == null) return;
|
|
fs.closeSync(obj.fd);
|
|
delete obj.fd;
|
|
}
|
|
|
|
// Private OIDS
|
|
obj.Oids = {
|
|
SPC_INDIRECT_DATA_OBJID: '1.3.6.1.4.1.311.2.1.4',
|
|
SPC_STATEMENT_TYPE_OBJID: '1.3.6.1.4.1.311.2.1.11',
|
|
SPC_SP_OPUS_INFO_OBJID: '1.3.6.1.4.1.311.2.1.12',
|
|
SPC_INDIVIDUAL_SP_KEY_PURPOSE_OBJID: '1.3.6.1.4.1.311.2.1.21',
|
|
SPC_COMMERCIAL_SP_KEY_PURPOSE_OBJID: '1.3.6.1.4.1.311.2.1.22',
|
|
SPC_MS_JAVA_SOMETHING: '1.3.6.1.4.1.311.15.1',
|
|
SPC_PE_IMAGE_DATA_OBJID: '1.3.6.1.4.1.311.2.1.15',
|
|
SPC_CAB_DATA_OBJID: '1.3.6.1.4.1.311.2.1.25',
|
|
SPC_TIME_STAMP_REQUEST_OBJID: '1.3.6.1.4.1.311.3.2.1',
|
|
SPC_SIPINFO_OBJID: '1.3.6.1.4.1.311.2.1.30',
|
|
SPC_PE_IMAGE_PAGE_HASHES_V1: '1.3.6.1.4.1.311.2.3.1',
|
|
SPC_PE_IMAGE_PAGE_HASHES_V2: '1.3.6.1.4.1.311.2.3.2',
|
|
SPC_NESTED_SIGNATURE_OBJID: '1.3.6.1.4.1.311.2.4.1',
|
|
SPC_RFC3161_OBJID: '1.3.6.1.4.1.311.3.3.1'
|
|
}
|
|
|
|
// Open the file and read header information
|
|
function openFile() {
|
|
if (obj.fd != null) return;
|
|
|
|
// Open the file descriptor
|
|
obj.path = path;
|
|
obj.fd = fs.openSync(path);
|
|
obj.stats = fs.fstatSync(obj.fd);
|
|
obj.filesize = obj.stats.size;
|
|
if (obj.filesize < 64) { throw ('File too short.'); }
|
|
|
|
// Read the PE header size
|
|
var buf = readFileSlice(60, 4);
|
|
obj.header.header_size = buf.readUInt32LE(0);
|
|
|
|
// Check file size and PE header
|
|
if (obj.filesize < (160 + obj.header.header_size)) { throw ('Invalid SizeOfHeaders.'); }
|
|
if (readFileSlice(obj.header.header_size, 4).toString('hex') != '50450000') { throw ('Invalid PE File.'); }
|
|
|
|
// Check header magic data
|
|
var magic = readFileSlice(obj.header.header_size + 24, 2).readUInt16LE(0);
|
|
switch (magic) {
|
|
case 0x20b: obj.header.pe32plus = 1; break;
|
|
case 0x10b: obj.header.pe32plus = 0; break;
|
|
default: throw ('Invalid Magic in PE');
|
|
}
|
|
|
|
// Read PE header information
|
|
obj.header.pe_checksum = readFileSlice(obj.header.header_size + 88, 4).readUInt32LE(0);
|
|
obj.header.numRVA = readFileSlice(obj.header.header_size + 116 + (obj.header.pe32plus * 16), 4).readUInt32LE(0);
|
|
buf = readFileSlice(obj.header.header_size + 152 + (obj.header.pe32plus * 16), 8);
|
|
obj.header.sigpos = buf.readUInt32LE(0);
|
|
obj.header.siglen = buf.readUInt32LE(4);
|
|
obj.header.signed = ((obj.header.sigpos != 0) && (obj.header.siglen != 0));
|
|
|
|
if (obj.header.signed) {
|
|
// Read signature block
|
|
|
|
// Check if the file size allows for the signature block
|
|
if (obj.filesize < (obj.header.sigpos + obj.header.siglen)) { throw ('Executable file too short to contain the signature block.'); }
|
|
|
|
// Remove the padding if needed
|
|
var i, pkcs7raw = readFileSlice(obj.header.sigpos + 8, obj.header.siglen - 8);
|
|
var derlen = forge.asn1.getBerValueLength(forge.util.createBuffer(pkcs7raw.slice(1, 5))) + 4;
|
|
if (derlen != pkcs7raw.length) { pkcs7raw = pkcs7raw.slice(0, derlen); }
|
|
|
|
//console.log('pkcs7raw', Buffer.from(pkcs7raw, 'binary').toString('base64'));
|
|
|
|
// Decode the signature block
|
|
var pkcs7der = forge.asn1.fromDer(forge.util.createBuffer(pkcs7raw));
|
|
|
|
// To work around ForgeJS PKCS#7 limitation, this may break PKCS7 verify if ForjeJS adds support for it in the future
|
|
// Switch content type from "1.3.6.1.4.1.311.2.1.4" to "1.2.840.113549.1.7.1"
|
|
pkcs7der.value[1].value[0].value[2].value[0].value = forge.asn1.oidToDer(forge.pki.oids.data).data;
|
|
|
|
// Decode the PKCS7 message
|
|
var pkcs7 = p7.messageFromAsn1(pkcs7der);
|
|
var pkcs7content = pkcs7.rawCapture.content.value[0];
|
|
|
|
/*
|
|
// Verify a PKCS#7 signature
|
|
// Verify is not currently supported in node-forge, but if implemented in the future, this code could work.
|
|
var caStore = forge.pki.createCaStore();
|
|
for (var i in obj.certificates) { caStore.addCertificate(obj.certificates[i]); }
|
|
// Return is true if all signatures are valid and chain up to a provided CA
|
|
if (!pkcs7.verify(caStore)) { throw ('Executable file has an invalid signature.'); }
|
|
*/
|
|
|
|
// Get the signing attributes
|
|
obj.signingAttribs = [];
|
|
for (var i in pkcs7.rawCapture.authenticatedAttributes) {
|
|
if (forge.asn1.derToOid(pkcs7.rawCapture.authenticatedAttributes[i].value[0].value) == obj.Oids.SPC_SP_OPUS_INFO_OBJID) {
|
|
for (var j in pkcs7.rawCapture.authenticatedAttributes[i].value[1].value[0].value) {
|
|
var v = pkcs7.rawCapture.authenticatedAttributes[i].value[1].value[0].value[j].value[0].value;
|
|
if (v.startsWith('http://') || v.startsWith('https://') || ((v.length % 2) == 1)) { obj.signingAttribs.push(v); } else {
|
|
var r = ""; // This string value is in UCS2 format, convert it to a normal string.
|
|
for (var k = 0; k < v.length; k += 2) { r += String.fromCharCode((v.charCodeAt(k + 8) << 8) + v.charCodeAt(k + 1)); }
|
|
obj.signingAttribs.push(r);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Set the certificate chain
|
|
obj.certificates = pkcs7.certificates;
|
|
|
|
// Get the file hashing algorithm
|
|
var hashAlgoOid = forge.asn1.derToOid(pkcs7content.value[1].value[0].value[0].value);
|
|
switch (hashAlgoOid) {
|
|
case forge.pki.oids.sha256: { obj.fileHashAlgo = 'sha256'; break; }
|
|
case forge.pki.oids.sha384: { obj.fileHashAlgo = 'sha384'; break; }
|
|
case forge.pki.oids.sha512: { obj.fileHashAlgo = 'sha512'; break; }
|
|
case forge.pki.oids.sha224: { obj.fileHashAlgo = 'sha224'; break; }
|
|
case forge.pki.oids.md5: { obj.fileHashAlgo = 'md5'; break; }
|
|
}
|
|
|
|
// Get the signed file hash
|
|
obj.fileHashSigned = Buffer.from(pkcs7content.value[1].value[1].value, 'binary')
|
|
|
|
// Compute the actual file hash
|
|
if (obj.fileHashAlgo != null) { obj.fileHashActual = getHash(obj.fileHashAlgo); }
|
|
}
|
|
}
|
|
|
|
// Hash the file using the selected hashing system
|
|
function getHash(algo) {
|
|
var hash = crypto.createHash(algo);
|
|
runHash(hash, 0, obj.header.header_size + 88);
|
|
runHash(hash, obj.header.header_size + 88 + 4, obj.header.header_size + 152 + (obj.header.pe32plus * 16));
|
|
runHash(hash, obj.header.header_size + 152 + (obj.header.pe32plus * 16) + 8, obj.header.sigpos > 0 ? obj.header.sigpos : obj.filesize);
|
|
return hash.digest();
|
|
}
|
|
|
|
// Hash the file from start to end loading 64k chunks
|
|
function runHash(hash, start, end) {
|
|
var ptr = start;
|
|
while (ptr < end) { const buf = readFileSlice(ptr, Math.min(65536, end - ptr)); hash.update(buf); ptr += buf.length; }
|
|
}
|
|
|
|
// Generate a test self-signed certificate with code signing extension
|
|
obj.createSelfSignedCert = function () {
|
|
var keys = pki.rsa.generateKeyPair(2048);
|
|
var cert = pki.createCertificate();
|
|
cert.publicKey = keys.publicKey;
|
|
cert.serialNumber = '00000001';
|
|
cert.validity.notBefore = new Date();
|
|
cert.validity.notAfter = new Date();
|
|
cert.validity.notAfter.setFullYear(cert.validity.notBefore.getFullYear() + 3);
|
|
var attrs = [
|
|
{ name: 'commonName', value: 'example.org' },
|
|
{ name: 'countryName', value: 'US' },
|
|
{ shortName: 'ST', value: 'California' },
|
|
{ name: 'localityName', value: 'Santa Clara' },
|
|
{ name: 'organizationName', value: 'Test' },
|
|
{ shortName: 'OU', value: 'Test' }
|
|
];
|
|
cert.setSubject(attrs);
|
|
cert.setIssuer(attrs);
|
|
cert.setExtensions([{ name: 'basicConstraints', cA: false }, { name: 'keyUsage', keyCertSign: false, digitalSignature: true, nonRepudiation: false, keyEncipherment: false, dataEncipherment: false }, { name: 'extKeyUsage', codeSigning: true }, { name: "subjectKeyIdentifier" }]);
|
|
cert.sign(keys.privateKey, forge.md.sha384.create());
|
|
return { cert: cert, key: keys.privateKey };
|
|
}
|
|
|
|
// Sign the file using the certificate and key. If none is specified, generate a dummy one
|
|
obj.sign = function (cert, key, desc, url) {
|
|
if ((cert == null) || (key == null)) { var c = obj.createSelfSignedCert(); cert = c.cert; key = c.key; }
|
|
var fileHash = getHash('sha384');
|
|
|
|
// Create the signature block
|
|
var p7 = forge.pkcs7.createSignedData();
|
|
var content = { "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [{ "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [{ "tagClass": 0, "type": 6, "constructed": false, "composed": false, "value": forge.asn1.oidToDer("1.3.6.1.4.1.311.2.1.15").data }, { "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [{ "tagClass": 0, "type": 3, "constructed": false, "composed": false, "value": "\u0000", "bitStringContents": "\u0000", "original": { "tagClass": 0, "type": 3, "constructed": false, "composed": false, "value": "\u0000" } }, { "tagClass": 128, "type": 0, "constructed": true, "composed": true, "value": [{ "tagClass": 128, "type": 2, "constructed": true, "composed": true, "value": [{ "tagClass": 128, "type": 0, "constructed": false, "composed": false, "value": "" }] }] }] }] }, { "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [{ "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [{ "tagClass": 0, "type": 6, "constructed": false, "composed": false, "value": forge.asn1.oidToDer(forge.pki.oids.sha384).data }, { "tagClass": 0, "type": 5, "constructed": false, "composed": false, "value": "" }] }, { "tagClass": 0, "type": 4, "constructed": false, "composed": false, "value": fileHash.toString('binary') }] }] };
|
|
p7.contentInfo = forge.asn1.create(forge.asn1.Class.UNIVERSAL, forge.asn1.Type.SEQUENCE, true, [forge.asn1.create(forge.asn1.Class.UNIVERSAL, forge.asn1.Type.OID, false, forge.asn1.oidToDer('1.3.6.1.4.1.311.2.1.4').getBytes())]);
|
|
p7.contentInfo.value.push(forge.asn1.create(forge.asn1.Class.CONTEXT_SPECIFIC, 0, true, [content]));
|
|
p7.content = {}; // We set .contentInfo and have .content empty to bypass node-forge limitation on the type of content it can sign.
|
|
p7.addCertificate(cert);
|
|
|
|
// Build authenticated attributes
|
|
var authenticatedAttributes = [
|
|
{ type: forge.pki.oids.contentType, value: forge.pki.oids.data },
|
|
{ type: forge.pki.oids.messageDigest } // value will be auto-populated at signing time
|
|
]
|
|
if ((desc != null) || (url != null)) {
|
|
var codeSigningAttributes = { "tagClass": 0, "type": 16, "constructed": true, "composed": true, "value": [ ] };
|
|
if (desc != null) { codeSigningAttributes.value.push({ "tagClass": 128, "type": 0, "constructed": true, "composed": true, "value": [{ "tagClass": 128, "type": 0, "constructed": false, "composed": false, "value": Buffer.from(desc, 'ucs2').toString() }] }); }
|
|
if (url != null) { codeSigningAttributes.value.push({ "tagClass": 128, "type": 1, "constructed": true, "composed": true, "value": [{ "tagClass": 128, "type": 0, "constructed": false, "composed": false, "value": url }] }); }
|
|
authenticatedAttributes.push({ type: obj.Oids.SPC_SP_OPUS_INFO_OBJID, value: codeSigningAttributes });
|
|
}
|
|
|
|
// Add the signer and sign
|
|
p7.addSigner({
|
|
key: key,
|
|
certificate: cert,
|
|
digestAlgorithm: forge.pki.oids.sha384,
|
|
authenticatedAttributes: authenticatedAttributes
|
|
});
|
|
p7.sign();
|
|
var p7signature = Buffer.from(forge.pkcs7.messageToPem(p7).split('-----BEGIN PKCS7-----')[1].split('-----END PKCS7-----')[0], 'base64');
|
|
//console.log('Signature', Buffer.from(p7signature, 'binary').toString('base64'));
|
|
|
|
// Create the output filename
|
|
var outputFileName = this.path.split('.');
|
|
outputFileName[outputFileName.length - 2] += '-jsigned';
|
|
outputFileName = outputFileName.join('.');
|
|
|
|
// Open the file
|
|
var output = fs.openSync(outputFileName, 'w');
|
|
var tmp, written = 0;
|
|
var executableSize = obj.header.sigpos ? obj.header.sigpos : this.filesize;
|
|
|
|
// Compute pre-header length and copy that to the new file
|
|
var preHeaderLen = (obj.header.header_size + 152 + (obj.header.pe32plus * 16));
|
|
var tmp = readFileSlice(written, preHeaderLen);
|
|
fs.writeSync(output, tmp);
|
|
written += tmp.length;
|
|
|
|
// Quad Align the results, adding padding if necessary
|
|
var len = executableSize + p7signature.length;
|
|
var padding = (8 - ((len) % 8)) % 8;
|
|
|
|
// Write the signature header
|
|
var addresstable = Buffer.alloc(8);
|
|
addresstable.writeUInt32LE(executableSize);
|
|
addresstable.writeUInt32LE(8 + p7signature.length + padding, 4);
|
|
fs.writeSync(output, addresstable);
|
|
written += addresstable.length;
|
|
|
|
// Copy the rest of the file until the start of the signature block
|
|
while ((executableSize - written) > 0) {
|
|
tmp = readFileSlice(written, Math.min(executableSize - written, 65536));
|
|
fs.writeSync(output, tmp);
|
|
written += tmp.length;
|
|
}
|
|
|
|
// Write the signature block header and signature
|
|
var win = Buffer.alloc(8); // WIN CERTIFICATE Structure
|
|
win.writeUInt32LE(p7signature.length + padding + 8); // DWORD length
|
|
win.writeUInt16LE(512, 4); // WORD revision
|
|
win.writeUInt16LE(2, 6); // WORD type
|
|
fs.writeSync(output, win);
|
|
fs.writeSync(output, p7signature);
|
|
if (padding > 0) { fs.writeSync(output, Buffer.alloc(padding, 0)); }
|
|
|
|
// Close the file
|
|
fs.closeSync(output);
|
|
}
|
|
|
|
// Save an executable without the signature
|
|
obj.unsign = function (cert, key) {
|
|
// Create the output filename
|
|
var outputFileName = this.path.split('.');
|
|
outputFileName[outputFileName.length - 2] += '-junsigned';
|
|
outputFileName = outputFileName.join('.');
|
|
|
|
// Open the file
|
|
var output = fs.openSync(outputFileName, 'w');
|
|
var written = 0, totalWrite = obj.header.sigpos;
|
|
|
|
// Compute pre-header length and copy that to the new file
|
|
var preHeaderLen = (obj.header.header_size + 152 + (obj.header.pe32plus * 16));
|
|
var tmp = readFileSlice(written, preHeaderLen);
|
|
fs.writeSync(output, tmp);
|
|
written += tmp.length;
|
|
|
|
// Write the new signature header
|
|
fs.writeSync(output, Buffer.alloc(8));
|
|
written += 8;
|
|
|
|
// Copy the rest of the file until the start of the signature block
|
|
while ((totalWrite - written) > 0) {
|
|
tmp = readFileSlice(written, Math.min(totalWrite - written, 65536));
|
|
fs.writeSync(output, tmp);
|
|
written += tmp.length;
|
|
}
|
|
fs.closeSync(output);
|
|
}
|
|
|
|
openFile();
|
|
return obj;
|
|
}
|
|
|
|
function start() {
|
|
// Parse the arguments
|
|
const args = require('minimist')(process.argv.slice(2));
|
|
|
|
// Show tool help
|
|
if (process.argv.length < 3) {
|
|
console.log("MeshCentral Authenticode Tool.");
|
|
console.log("Usage:");
|
|
console.log(" node authenticode.js [command] [options]");
|
|
console.log("Commands:");
|
|
console.log(" info: Show information about an executable.");
|
|
console.log(" --json Optional, Show information in JSON format.");
|
|
console.log(" sign: Sign an executable.");
|
|
console.log(" --exe [file] Executable to sign.");
|
|
console.log(" --out [file] Optional resulting signed executable.");
|
|
console.log(" --cert [pemfile] Certificate to sign the executable with.");
|
|
console.log(" --key [pemfile] Private key to use to sign the executable.");
|
|
console.log(" --desc [description] Optional description string to embbed into signature.");
|
|
console.log(" --url [url] Optional URL to embbed into signature.");
|
|
console.log(" unsign: Remove the signature from the executable.");
|
|
console.log(" --exe [file] Executable to un-sign.");
|
|
console.log(" --out [file] Optional resulting executable with signature removed.");
|
|
console.log(" createcert: Create a self-signed certificate and key.");
|
|
console.log(" --cn [commonName] Certificate common name.");
|
|
return;
|
|
}
|
|
|
|
// Check that a valid command is passed in
|
|
if (['info', 'sign', 'unsign', 'createcert'].indexOf(process.argv[2].toLowerCase()) == -1) {
|
|
console.log("Invalid command: " + process.argv[2]);
|
|
console.log("Valid commands are: info, sign, unsign, createcert");
|
|
return;
|
|
}
|
|
|
|
var exe = null;
|
|
if (args.exe) {
|
|
// Check the file exists and open the file
|
|
var stats = null;
|
|
try { stats = require('fs').statSync(args.exe); } catch (ex) { }
|
|
if (stats == null) { console.log("Unable to executable open file: " + args.exe); return; }
|
|
exe = createAuthenticodeHandler(args.exe);
|
|
}
|
|
|
|
// Execute the command
|
|
var command = process.argv[2].toLowerCase();
|
|
if (command == 'info') {
|
|
if (exe == null) { console.log("Missing --exe [filename]"); return; }
|
|
if (args.json) {
|
|
var r = { header: exe.header, filesize: exe.filesize }
|
|
if (exe.fileHashAlgo != null) { r.hashMethod = exe.fileHashAlgo; }
|
|
if (exe.fileHashSigned != null) { r.hashSigned = exe.fileHashSigned.toString('hex'); }
|
|
if (exe.fileHashActual != null) { r.hashActual = exe.fileHashActual.toString('hex'); }
|
|
if (exe.signingAttribs && exe.signingAttribs.length > 0) { r.signAttributes = exe.signingAttribs; }
|
|
console.log(JSON.stringify(r, null, 2));
|
|
} else {
|
|
console.log('Header', exe.header);
|
|
if (exe.fileHashAlgo != null) { console.log('fileHashMethod:', exe.fileHashAlgo); }
|
|
if (exe.fileHashSigned != null) { console.log('fileHashSigned:', exe.fileHashSigned.toString('hex')); }
|
|
if (exe.fileHashActual != null) { console.log('fileHashActual:', exe.fileHashActual.toString('hex')); }
|
|
if (exe.signingAttribs && exe.signingAttribs.length > 0) { console.log('Signature Attributes:'); for (var i in exe.signingAttribs) { console.log(' ' + exe.signingAttribs[i]); } }
|
|
console.log('FileLen: ' + exe.filesize);
|
|
}
|
|
}
|
|
if (command == 'sign') {
|
|
if (exe == null) { console.log("Missing --exe [filename]"); return; }
|
|
var desc = null, url = null;
|
|
if (process.argv.length > 4) { desc = process.argv[4]; }
|
|
if (process.argv.length > 5) { url = process.argv[5]; }
|
|
console.log('Signing...'); exe.sign(null, null, desc, url); console.log('Done.');
|
|
}
|
|
if (command == 'unsign') {
|
|
if (exe == null) { console.log("Missing --exe [filename]"); return; }
|
|
if (exe.header.signed) { console.log('Unsigning...'); exe.unsign(); console.log('Done.'); } else { console.log('Executable is not signed.'); }
|
|
}
|
|
if (command == 'createcert') {
|
|
|
|
}
|
|
|
|
// Close the file
|
|
if (exe != null) { exe.close(); }
|
|
}
|
|
|
|
start(); |