Initial commit

src/js/lib/jsbn/rng.js

@@ -0,0 +1,76 @@
+// Random number generator - requires a PRNG backend, e.g. prng4.js
+// For best results, put code like
+// <body onClick='rng_seed_time();' onKeyPress='rng_seed_time();'>
+// in your main HTML document.
+
+var rng_state;
+var rng_pool;
+var rng_pptr;
+
+// Mix in a 32-bit integer into the pool
+function rng_seed_int(x) {
+	rng_pool[rng_pptr++] ^= x & 255;
+	rng_pool[rng_pptr++] ^= x >> 8 & 255;
+	// rng_pool[rng_pptr++] ^= x >> 16 & 255;
+	// rng_pool[rng_pptr++] ^= x >> 24 & 255;
+	if (rng_pptr >= rng_psize)
+		rng_pptr -= rng_psize;
+}
+
+// Mix in the current time (w/milliseconds) into the pool
+function rng_seed_time() {
+	rng_seed_int(new Date().getTime());
+}
+
+// Initialize the pool with junk if needed.
+if (rng_pool == null) {
+	rng_pool = new Array();
+	rng_pptr = 0;
+	var t;
+	if (window.crypto && window.crypto.getRandomValues) {
+		// Use webcrypto if available
+		var ua = new Uint8Array(32);
+		window.crypto.getRandomValues(ua);
+		for (t = 0; t < 32; ++t)
+			rng_pool[rng_pptr++] = ua[t];
+	}
+	if (navigator.appName == 'Netscape' && navigator.appVersion < '5' && window.crypto) {
+		// Extract entropy (256 bits) from NS4 RNG if available
+		var z = window.crypto.random(32);
+		for (t = 0; t < z.length; ++t)
+			rng_pool[rng_pptr++] = z.charCodeAt(t) & 255;
+	}
+	while (rng_pptr < rng_psize) {
+		// extract some randomness from Math.random()
+		t = Math.floor(65536 * Math.random());
+		rng_pool[rng_pptr++] = t >>> 8;
+		rng_pool[rng_pptr++] = t & 255;
+	}
+	rng_pptr = 0;
+	rng_seed_time();
+	//rng_seed_int(window.screenX);
+	//rng_seed_int(window.screenY);
+}
+
+function rng_get_byte() {
+	if (rng_state == null) {
+		rng_seed_time();
+		rng_state = prng_newstate();
+		rng_state.init(rng_pool);
+		for (rng_pptr = 0; rng_pptr < rng_pool.length; ++rng_pptr)
+			rng_pool[rng_pptr] = 0;
+		rng_pptr = 0;
+		//rng_pool = null;
+	}
+	// TODO: allow reseeding after first request
+	return rng_state.next();
+}
+
+function rng_get_bytes(ba) {
+	var i;
+	for (i = 0; i < ba.length; ++i)
+		ba[i] = rng_get_byte();
+}
+
+function SecureRandom() {}
+SecureRandom.prototype.nextBytes = rng_get_bytes;