From 9b327683b4c0b8504724aca213e08d484c290804 Mon Sep 17 00:00:00 2001
From: Kyle Spearrin <kyle.spearrin@gmail.com>
Date: Tue, 9 Jan 2018 17:45:21 -0500
Subject: [PATCH] convert totp service to jslib

---
 src/abstractions/index.ts        |   1 +
 src/abstractions/totp.service.ts |   4 ++
 src/services/index.ts            |   1 +
 src/services/totp.service.ts     | 118 +++++++++++++++++++++++++++++++
 4 files changed, 124 insertions(+)
 create mode 100644 src/abstractions/totp.service.ts
 create mode 100644 src/services/totp.service.ts

diff --git a/src/abstractions/index.ts b/src/abstractions/index.ts
index b2348f7326..d026e4c372 100644
--- a/src/abstractions/index.ts
+++ b/src/abstractions/index.ts
@@ -5,5 +5,6 @@ export { MessagingService } from './messaging.service';
 export { PlatformUtilsService } from './platformUtils.service';
 export { StorageService } from './storage.service';
 export { TokenService } from './token.service';
+export { TotpService } from './totp.service';
 export { UserService } from './user.service';
 export { UtilsService } from './utils.service';
diff --git a/src/abstractions/totp.service.ts b/src/abstractions/totp.service.ts
new file mode 100644
index 0000000000..2e8fa79aa7
--- /dev/null
+++ b/src/abstractions/totp.service.ts
@@ -0,0 +1,4 @@
+export interface TotpService {
+    getCode(keyb32: string): Promise<string>;
+    isAutoCopyEnabled(): Promise<boolean>;
+}
diff --git a/src/services/index.ts b/src/services/index.ts
index 1ef71d40bb..67e7b6aa59 100644
--- a/src/services/index.ts
+++ b/src/services/index.ts
@@ -3,5 +3,6 @@ export { AppIdService } from './appId.service';
 export { ConstantsService } from './constants.service';
 export { CryptoService } from './crypto.service';
 export { TokenService } from './token.service';
+export { TotpService } from './totp.service';
 export { UserService } from './user.service';
 export { UtilsService } from './utils.service';
diff --git a/src/services/totp.service.ts b/src/services/totp.service.ts
new file mode 100644
index 0000000000..ac6cc4cb78
--- /dev/null
+++ b/src/services/totp.service.ts
@@ -0,0 +1,118 @@
+import { ConstantsService } from './constants.service';
+
+import { StorageService } from '../abstractions/storage.service';
+import { TotpService as TotpServiceInterface } from '../abstractions/totp.service';
+
+const b32Chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ234567';
+
+const TotpAlgorithm = {
+    name: 'HMAC',
+    hash: { name: 'SHA-1' },
+};
+
+export class TotpService implements TotpServiceInterface {
+    constructor(private storageService: StorageService) {
+    }
+
+    async getCode(keyb32: string): Promise<string> {
+        const epoch = Math.round(new Date().getTime() / 1000.0);
+        const timeHex = this.leftpad(this.dec2hex(Math.floor(epoch / 30)), 16, '0');
+        const timeBytes = this.hex2bytes(timeHex);
+        const keyBytes = this.b32tobytes(keyb32);
+
+        if (!keyBytes.length || !timeBytes.length) {
+            return null;
+        }
+
+        const hashHex = await this.sign(keyBytes, timeBytes);
+        if (!hashHex) {
+            return null;
+        }
+
+        const offset = this.hex2dec(hashHex.substring(hashHex.length - 1));
+        // tslint:disable-next-line
+        let otp = (this.hex2dec(hashHex.substr(offset * 2, 8)) & this.hex2dec('7fffffff')) + '';
+        otp = (otp).substr(otp.length - 6, 6);
+        return otp;
+    }
+
+    async isAutoCopyEnabled(): Promise<boolean> {
+        return !(await this.storageService.get<boolean>(ConstantsService.disableAutoTotpCopyKey));
+    }
+
+    // Helpers
+
+    private leftpad(s: string, l: number, p: string): string {
+        if (l + 1 >= s.length) {
+            s = Array(l + 1 - s.length).join(p) + s;
+        }
+        return s;
+    }
+
+    private dec2hex(d: number): string {
+        return (d < 15.5 ? '0' : '') + Math.round(d).toString(16);
+    }
+
+    private hex2dec(s: string): number {
+        return parseInt(s, 16);
+    }
+
+    private hex2bytes(s: string): Uint8Array {
+        const bytes = new Uint8Array(s.length / 2);
+        for (let i = 0; i < s.length; i += 2) {
+            bytes[i / 2] = parseInt(s.substr(i, 2), 16);
+        }
+        return bytes;
+    }
+
+    private buff2hex(buff: ArrayBuffer): string {
+        const bytes = new Uint8Array(buff);
+        const hex: string[] = [];
+        bytes.forEach((b) => {
+            // tslint:disable-next-line
+            hex.push((b >>> 4).toString(16));
+            // tslint:disable-next-line
+            hex.push((b & 0xF).toString(16));
+        });
+        return hex.join('');
+    }
+
+    private b32tohex(s: string): string {
+        s = s.toUpperCase();
+        let cleanedInput = '';
+
+        for (let i = 0; i < s.length; i++) {
+            if (b32Chars.indexOf(s[i]) < 0) {
+                continue;
+            }
+
+            cleanedInput += s[i];
+        }
+        s = cleanedInput;
+
+        let bits = '';
+        let hex = '';
+        for (let i = 0; i < s.length; i++) {
+            const byteIndex = b32Chars.indexOf(s.charAt(i));
+            if (byteIndex < 0) {
+                continue;
+            }
+            bits += this.leftpad(byteIndex.toString(2), 5, '0');
+        }
+        for (let i = 0; i + 4 <= bits.length; i += 4) {
+            const chunk = bits.substr(i, 4);
+            hex = hex + parseInt(chunk, 2).toString(16);
+        }
+        return hex;
+    }
+
+    private b32tobytes(s: string): Uint8Array {
+        return this.hex2bytes(this.b32tohex(s));
+    }
+
+    private async sign(keyBytes: Uint8Array, timeBytes: Uint8Array) {
+        const key = await window.crypto.subtle.importKey('raw', keyBytes, TotpAlgorithm, false, ['sign']);
+        const signature = await window.crypto.subtle.sign(TotpAlgorithm, key, timeBytes);
+        return this.buff2hex(signature);
+    }
+}