officecrypto-tool - npm Package Compare versions

Comparing version 0.0.2 to 0.0.3

index.d.ts

@@ -19,2 +19,8 @@
         password: string;
+
+        /**
+         * @desc Encryption Type
+         * optional
+         */
+        type?: 'standard';
     }
@@ -21,0 +27,0 @@

index.js

@@ -17,3 +17,10 @@ /* eslint-disable valid-jsdoc */
 async function decrypt(input, options) {
-  if (!Buffer.isBuffer(input)) throw new Error('The input must be a buffer');
+  if (!Buffer.isBuffer(input)) {
+    // This is an ArrayBuffer in the browser. Convert to a Buffer.
+    if (ArrayBuffer.isView(input)) {
+      input = Buffer.from(input);
+    } else {
+      throw new Error('The input must be a buffer');
+    }
+  }
   if (!options || !options.password) throw new Error('options.password is required');
@@ -24,3 +31,3 @@
 
-  if (encryptionInfo) { // 这个是xlsx格式的加密
+  if (encryptionInfo) { // This is encrypted in xlsx format
     const encryptedPackage = CFB.find(cfb, '/EncryptedPackage');
@@ -69,3 +76,10 @@ const einfo = common.parseEncryptionInfo(encryptionInfo.content);
 function encrypt(input, options) {
-  if (!Buffer.isBuffer(input)) throw new Error('The input must be a buffer');
+  if (!Buffer.isBuffer(input)) {
+    // This is an ArrayBuffer in the browser. Convert to a Buffer.
+    if (ArrayBuffer.isView(input)) {
+      input = Buffer.from(input);
+    } else {
+      throw new Error('The input must be a buffer');
+    }
+  }
   if (!options || !options.password) throw new Error('options.password is required');
@@ -75,3 +89,12 @@
   if (options.password.length > maxFieldLength) throw new Error(`The maximum password length is ${maxFieldLength}`);
-  const output = ecma376Agile.encrypt(input, options.password);
+  let output;
+
+  if (options.hasOwnProperty('type') && !['standard'].includes(options.type)) {
+    throw new Error(`options.type must be ['standard']`);
+  }
+  if (options.type === 'standard') {
+    output = ecma376Standard.encryptStandard(input, options.password);
+  } else {
+    output = ecma376Agile.encrypt(input, options.password);
+  }
   return output;
@@ -78,0 +101,0 @@ }

package.json

 {
   "name": "officecrypto-tool",
-  "version": "0.0.2",
+  "version": "0.0.3",
   "description": "officeCrypto is a library for node.js that can be used to decrypt and encrypt excel files.",
@@ -15,2 +15,3 @@ "keywords": [
   "private": false,
+  "license": "MIT",
   "author": "zurmokeeper",
@@ -17,0 +18,0 @@ "main": "index.js",

src/crypto/ecma376_standard.js

@@ -5,4 +5,5 @@ /* eslint-disable require-jsdoc */
 const crypto = require('crypto');
+const cfb = require('cfb');
 
-exports.convertPasswordToKey = function convertPasswordToKey(password, algId, algIdHash, providerType, keySize, saltSize, salt) {
+const convertPasswordToKey = exports.convertPasswordToKey = function convertPasswordToKey(password, algId, algIdHash, providerType, keySize, saltSize, salt) {
   const ITER_COUNT = 50000;
@@ -46,2 +47,6 @@ const cbRequiredKeyLength = keySize / 8;
 exports.verifyKey = function verifyKey(key, encryptedVerifier, encryptedVerifierHash) {
+  // In the browser environment. Convert to a Buffer.
+  if (!Buffer.isBuffer(encryptedVerifier)) encryptedVerifier = Buffer.from(encryptedVerifier);
+  if (!Buffer.isBuffer(encryptedVerifierHash)) encryptedVerifierHash = Buffer.from(encryptedVerifierHash);
+
   const aes = crypto.createDecipheriv('aes-128-ecb', key, Buffer.alloc(0));
@@ -64,2 +69,5 @@ aes.setAutoPadding(false);
 
+  // In the browser environment. Convert to a Buffer.
+  if (!Buffer.isBuffer(input)) input = Buffer.from(input);
+
   // The package is encoded in chunks. Encrypt/decrypt each and concat.
@@ -94,3 +102,3 @@ let start = 0; let end = 0;
 
-exports.encrypt = function encrypt(key, input) {
+const encrypt = exports.encrypt = function encrypt(key, input) {
   const outputChunks = [];
@@ -122,3 +130,2 @@ const offset = 0;
 
-
   // Concat all of the output chunks.
@@ -138,1 +145,89 @@ let output = Buffer.concat(outputChunks);
 }
+
+function genVerifier(key) {
+  const verifierHashInput = crypto.randomBytes(16);
+  const aes = crypto.createCipheriv('aes-128-ecb', key, Buffer.alloc(0));
+  aes.setAutoPadding(false);
+  const verifierHashInputValue = Buffer.concat([aes.update(verifierHashInput), aes.final()]);
+
+  let verifierHashInputKey = crypto.createHash('sha1').update(verifierHashInput).digest();
+  const blockSize = 16;
+  const remainder = verifierHashInputKey.length % blockSize;
+  if (remainder) verifierHashInputKey = Buffer.concat([verifierHashInputKey, Buffer.alloc(blockSize - remainder)]);
+
+  const aes2 = crypto.createCipheriv('aes-128-ecb', key, Buffer.alloc(0));
+  aes2.setAutoPadding(false);
+  const verifierHashInputKeyValue = Buffer.concat([aes2.update(verifierHashInputKey), aes2.final()]);
+  return {encryptedVerifier: verifierHashInputValue, encryptedVerifierHash: verifierHashInputKeyValue};
+}
+
+function buildEncryptionInfo(key, keyDataSaltValue) {
+  const blob = Buffer.alloc(224);
+  cfb.utils.prep_blob(blob, 0);
+
+  blob.write_shift(2, 0x0004);
+  blob.write_shift(2, 0x0002);
+  blob.write_shift(4, 0x24); // EncryptionHeaderFlags
+  blob.write_shift(4, 0x8c); // 140  EncryptionHeaderSize
+  blob.write_shift(4, 0x24); // Flags
+  blob.write_shift(4, 0x00); // SizeExtra
+  blob.write_shift(4, 0x660E); // AlgID
+  blob.write_shift(4, 0x8004); // AlgIDHash
+  blob.write_shift(4, 0x80); // KeySize  128
+  blob.write_shift(4, 0x18); // ProviderType;
+  blob.write_shift(4, 0x00); // Reserved1
+  blob.write_shift(4, 0x00); // Reserved2
+
+  // The entire EncryptionHeaderSize is 140 bytes, the above is already 32 bytes, leaving 108 bytes, since it is utf16le
+  // so providerName = 108/2 = 54
+
+  const providerName = 'Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)';
+  blob.write_shift(54, providerName, 'utf16le');
+
+  blob.write_shift(4, 0x10); // SaltSize
+
+  const {encryptedVerifier, encryptedVerifierHash} = genVerifier(key);
+
+  blob.write_shift(16, keyDataSaltValue.toString('hex'), 'hex'); // Salt
+  blob.write_shift(16, encryptedVerifier.toString('hex'), 'hex'); // EncryptedVerifier
+  blob.write_shift(4, 0x14); // VerifierHashSize
+  blob.write_shift(32, encryptedVerifierHash.toString('hex'), 'hex'); // EncryptedVerifierHash
+
+  return blob;
+}
+
+function buildEncryptionPackage(key, input) {
+  const output = encrypt(key, input);
+  return output;
+}
+
+exports.encryptStandard = function encryptStandard(input, password) {
+  // Create a new CFB
+  let output = cfb.utils.cfb_new();
+
+  const KeySize = 128;
+  const AlgID = 0x660E;
+  const AlgIDHash = 0x8004;
+  const ProviderType = 0x18;
+  const saltSize = 16;
+  const keyDataSaltValue = crypto.randomBytes(16);
+  const key = convertPasswordToKey(password, AlgID, AlgIDHash, ProviderType, KeySize, saltSize, keyDataSaltValue);
+
+  const encryptionInfoBuffer = buildEncryptionInfo(key, keyDataSaltValue);
+  const encryptedPackage = buildEncryptionPackage(key, input);
+
+  // Add the encryption info and encrypted package
+  cfb.utils.cfb_add(output, 'EncryptionInfo', encryptionInfoBuffer);
+  cfb.utils.cfb_add(output, 'EncryptedPackage', encryptedPackage);
+
+  // Delete the SheetJS entry that is added at initialization
+  cfb.utils.cfb_del(output, '\u0001Sh33tJ5');
+
+  // Write to a buffer and return
+  output = cfb.write(output);
+
+  // The cfb library writes to a Uint8array in the browser. Convert to a Buffer.
+  if (!Buffer.isBuffer(output)) output = Buffer.from(output);
+
+  return output;
+};

tests/ecma376_standard/encrypt.test.js

@@ -7,8 +7,34 @@
 
-const filePath = './tests/data/decrypt';
+const filePath = './tests/data/encrypt';
 
 describe('ecma376_standard encrypt', () => {
   it('encrypt', async () => {
-    expect(200).toEqual(200);
+    const input = await fs.readFile(`${filePath}/standard_wait_for_encrypt.xlsx`);
+
+    const output = officeCrypto.encrypt(input, {password: '123456', type: 'standard'});
+    await fs.writeFile(`${filePath}/standard_encrypt_finish.xlsx`, output);
+    // expect(200).toEqual(200);
   });
+
+  it(`options.type must be ['standard'], options.type= ''`, async () => {
+    const test = function test() {
+      return async function() {
+        const input = await fs.readFile(`${filePath}/standard_wait_for_encrypt.xlsx`);
+
+        const output = officeCrypto.encrypt(input, {password: '123456', type: ''});
+      };
+    };
+    await expect(test()).rejects.toThrowError(new Error( `options.type must be ['standard']` ));
+  });
+
+  it(`options.type must be ['standard'], options.type= 'xx'`, async () => {
+    const test = function test() {
+      return async function() {
+        const input = await fs.readFile(`${filePath}/standard_wait_for_encrypt.xlsx`);
+
+        const output = officeCrypto.encrypt(input, {password: '123456', type: 'xx'});
+      };
+    };
+    await expect(test()).rejects.toThrowError(new Error( `options.type must be ['standard']` ));
+  });
 });

No alert changes

Improved metrics

Total package byte prevSize

165019

increased by18.93%

Number of package files

29

increased by11.54%

Lines of code

1218

increased by11.13%

No dependency changes