More new crypto -- poly1305 one-time auth code.

node/Poly1305.cpp

@@ -0,0 +1,147 @@
+/*
+ * ZeroTier One - Global Peer to Peer Ethernet
+ * Copyright (C) 2012-2013  ZeroTier Networks LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * --
+ *
+ * ZeroTier may be used and distributed under the terms of the GPLv3, which
+ * are available at: http://www.gnu.org/licenses/gpl-3.0.html
+ *
+ * If you would like to embed ZeroTier into a commercial application or
+ * redistribute it in a modified binary form, please contact ZeroTier Networks
+ * LLC. Start here: http://www.zerotier.com/
+ */
+
+#include "Poly1305.hpp"
+
+namespace ZeroTier {
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+
+/*
+20080912
+D. J. Bernstein
+Public domain.
+*/
+
+static void add(unsigned int h[17],const unsigned int c[17])
+{
+  unsigned int j;
+  unsigned int u;
+  u = 0;
+  for (j = 0;j < 17;++j) { u += h[j] + c[j]; h[j] = u & 255; u >>= 8; }
+}
+
+static void squeeze(unsigned int h[17])
+{
+  unsigned int j;
+  unsigned int u;
+  u = 0;
+  for (j = 0;j < 16;++j) { u += h[j]; h[j] = u & 255; u >>= 8; }
+  u += h[16]; h[16] = u & 3;
+  u = 5 * (u >> 2);
+  for (j = 0;j < 16;++j) { u += h[j]; h[j] = u & 255; u >>= 8; }
+  u += h[16]; h[16] = u;
+}
+
+static const unsigned int minusp[17] = {
+  5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 252
+} ;
+
+static void freeze(unsigned int h[17])
+{
+  unsigned int horig[17];
+  unsigned int j;
+  unsigned int negative;
+  for (j = 0;j < 17;++j) horig[j] = h[j];
+  add(h,minusp);
+  negative = -(h[16] >> 7);
+  for (j = 0;j < 17;++j) h[j] ^= negative & (horig[j] ^ h[j]);
+}
+
+static void mulmod(unsigned int h[17],const unsigned int r[17])
+{
+  unsigned int hr[17];
+  unsigned int i;
+  unsigned int j;
+  unsigned int u;
+
+  for (i = 0;i < 17;++i) {
+    u = 0;
+    for (j = 0;j <= i;++j) u += h[j] * r[i - j];
+    for (j = i + 1;j < 17;++j) u += 320 * h[j] * r[i + 17 - j];
+    hr[i] = u;
+  }
+  for (i = 0;i < 17;++i) h[i] = hr[i];
+  squeeze(h);
+}
+
+static int crypto_onetimeauth(unsigned char *out,const unsigned char *in,unsigned long long inlen,const unsigned char *k)
+{
+  unsigned int j;
+  unsigned int r[17];
+  unsigned int h[17];
+  unsigned int c[17];
+
+  r[0] = k[0];
+  r[1] = k[1];
+  r[2] = k[2];
+  r[3] = k[3] & 15;
+  r[4] = k[4] & 252;
+  r[5] = k[5];
+  r[6] = k[6];
+  r[7] = k[7] & 15;
+  r[8] = k[8] & 252;
+  r[9] = k[9];
+  r[10] = k[10];
+  r[11] = k[11] & 15;
+  r[12] = k[12] & 252;
+  r[13] = k[13];
+  r[14] = k[14];
+  r[15] = k[15] & 15;
+  r[16] = 0;
+
+  for (j = 0;j < 17;++j) h[j] = 0;
+
+  while (inlen > 0) {
+    for (j = 0;j < 17;++j) c[j] = 0;
+    for (j = 0;(j < 16) && (j < inlen);++j) c[j] = in[j];
+    c[j] = 1;
+    in += j; inlen -= j;
+    add(h,c);
+    mulmod(h,r);
+  }
+
+  freeze(h);
+
+  for (j = 0;j < 16;++j) c[j] = k[j + 16];
+  c[16] = 0;
+  add(h,c);
+  for (j = 0;j < 16;++j) out[j] = h[j];
+  return 0;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+
+void Poly1305::computeAuthCode(void *auth,const void *data,unsigned int len,const void *key)
+	throw()
+{
+	crypto_onetimeauth((unsigned char *)auth,(const unsigned char *)data,len,(const unsigned char *)key);
+}
+
+} // namespace ZeroTier

node/Poly1305.hpp

@@ -0,0 +1,53 @@
+/*
+ * ZeroTier One - Global Peer to Peer Ethernet
+ * Copyright (C) 2012-2013  ZeroTier Networks LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * --
+ *
+ * ZeroTier may be used and distributed under the terms of the GPLv3, which
+ * are available at: http://www.gnu.org/licenses/gpl-3.0.html
+ *
+ * If you would like to embed ZeroTier into a commercial application or
+ * redistribute it in a modified binary form, please contact ZeroTier Networks
+ * LLC. Start here: http://www.zerotier.com/
+ */
+
+#ifndef _ZT_POLY1305_HPP
+#define _ZT_POLY1305_HPP
+
+namespace ZeroTier {
+
+/**
+ * Poly1305 one-time authentication code
+ */
+class Poly1305
+{
+public:
+	/**
+	 * Compute a one-time authentication code
+	 *
+	 * @param auth Buffer to receive code -- MUST be 16 bytes in length
+	 * @param data Data to authenticate
+	 * @param len Length of data to authenticate in bytes
+	 * @param key 32-byte one-time use key to authenticate data (must not be reused)
+	 */
+	static void computeAuthCode(void *auth,const void *data,unsigned int len,const void *key)
+		throw();
+};
+
+} // namespace ZeroTier
+
+#endif

objects.mk

@@ -18,6 +18,7 @@ OBJS=\
 	node/Packet.o \
 	node/PacketDecoder.o \
 	node/Peer.o \
+	node/Poly1305.o \
 	node/Salsa20.o \
 	node/Service.o \
 	node/SHA512.o \