Add reference ChaCha20 and Poly1305 implementations.

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@openssl.org>

2 files changed, 224 insertions, 0 deletions

diff --git a/crypto/chacha/Makefile b/crypto/chacha/Makefile
new file mode 100644
index 0000000000..cd249b1adf
--- /dev/null
+++ b/crypto/chacha/Makefile
@@ -0,0 +1,67 @@
+#
+# OpenSSL/crypto/chacha/Makefile
+#
+
+DIR=	chacha
+TOP=	../..
+CC=	cc
+CPP=    $(CC) -E
+INCLUDES=
+CFLAG=-g
+AR=		ar r
+
+CHACHA_ENC=chacha_enc.o
+
+CFLAGS= $(INCLUDES) $(CFLAG)
+ASFLAGS= $(INCLUDES) $(ASFLAG)
+AFLAGS= $(ASFLAGS)
+
+GENERAL=Makefile
+TEST=chachatest.c
+APPS=
+
+LIB=$(TOP)/libcrypto.a
+LIBSRC=chacha_enc.c
+LIBOBJ=$(CHACHA_ENC)
+
+SRC= $(LIBSRC)
+
+ALL=    $(GENERAL) $(SRC) $(HEADER)
+
+top:
+	(cd ../..; $(MAKE) DIRS=crypto SDIRS=$(DIR) sub_all)
+
+all:	lib
+
+lib:	$(LIBOBJ)
+	$(AR) $(LIB) $(LIBOBJ)
+	$(RANLIB) $(LIB) || echo Never mind.
+	@touch lib
+
+files:
+	$(PERL) $(TOP)/util/files.pl Makefile >> $(TOP)/MINFO
+
+tags:
+	ctags $(SRC)
+
+tests:
+
+lint:
+	lint -DLINT $(INCLUDES) $(SRC)>fluff
+
+update:	depend
+
+depend:
+	@[ -n "$(MAKEDEPEND)" ] # should be set by upper Makefile...
+	$(MAKEDEPEND) -- $(CFLAG) $(INCLUDES) $(DEPFLAG) -- $(PROGS) $(LIBSRC)
+
+dclean:
+	$(PERL) -pe 'if (/^# DO NOT DELETE THIS LINE/) {print; exit(0);}' $(MAKEFILE) >Makefile.new
+	mv -f Makefile.new $(MAKEFILE)
+
+clean:
+	rm -f *.s *.o *.obj lib tags core .pure .nfs* *.old *.bak fluff
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+chacha_enc.o: ../include/internal/chacha.h chacha_enc.c
diff --git a/crypto/chacha/chacha_enc.c b/crypto/chacha/chacha_enc.c
new file mode 100644
index 0000000000..281a9be8a8
--- /dev/null
+++ b/crypto/chacha/chacha_enc.c
@@ -0,0 +1,157 @@
+/* ====================================================================
+ * Copyright (c) 2011-2013 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    licensing@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ */
+
+/* Adapted from the public domain code by D. Bernstein from SUPERCOP. */
+
+#include <string.h>
+
+#include "internal/chacha.h"
+
+typedef unsigned int u32;
+typedef unsigned char u8;
+typedef union {
+    u32 u[16];
+    u8 c[64];
+} chacha_buf;
+
+# define ROTATE(v, n) (((v) << (n)) | ((v) >> (32 - (n))))
+
+# define U32TO8_LITTLE(p, v) do { \
+                                (p)[0] = (u8)(v >>  0); \
+                                (p)[1] = (u8)(v >>  8); \
+                                (p)[2] = (u8)(v >> 16); \
+                                (p)[3] = (u8)(v >> 24); \
+                                } while(0)
+
+/* QUARTERROUND updates a, b, c, d with a ChaCha "quarter" round. */
+# define QUARTERROUND(a,b,c,d) ( \
+                x[a] += x[b], x[d] = ROTATE((x[d] ^ x[a]),16), \
+                x[c] += x[d], x[b] = ROTATE((x[b] ^ x[c]),12), \
+                x[a] += x[b], x[d] = ROTATE((x[d] ^ x[a]), 8), \
+                x[c] += x[d], x[b] = ROTATE((x[b] ^ x[c]), 7)  )
+
+/* chacha_core performs 20 rounds of ChaCha on the input words in
+ * |input| and writes the 64 output bytes to |output|. */
+static void chacha20_core(chacha_buf *output, const u32 input[16])
+{
+    u32 x[16];
+    int i;
+    const union {
+        long one;
+        char little;
+    } is_endian = { 1 };
+
+    memcpy(x, input, sizeof(x));
+
+    for (i = 20; i > 0; i -= 2) {
+        QUARTERROUND(0, 4, 8, 12);
+        QUARTERROUND(1, 5, 9, 13);
+        QUARTERROUND(2, 6, 10, 14);
+        QUARTERROUND(3, 7, 11, 15);
+        QUARTERROUND(0, 5, 10, 15);
+        QUARTERROUND(1, 6, 11, 12);
+        QUARTERROUND(2, 7, 8, 13);
+        QUARTERROUND(3, 4, 9, 14);
+    }
+
+    if (is_endian.little) {
+        for (i = 0; i < 16; ++i)
+            output->u[i] = x[i] + input[i];
+    } else {
+        for (i = 0; i < 16; ++i)
+            U32TO8_LITTLE(output->c + 4 * i, (x[i] + input[i]));
+    }
+}
+
+void ChaCha20_ctr32(unsigned char *out, const unsigned char *inp,
+                    size_t len, const unsigned int key[8],
+                    const unsigned int counter[4])
+{
+    u32 input[16];
+    chacha_buf buf;
+    size_t todo, i;
+
+    /* sigma constant "expand 32-byte k" in little-endian encoding */
+    input[0] = ((u32)'e') | ((u32)'x'<<8) | ((u32)'p'<<16) | ((u32)'a'<<24);
+    input[1] = ((u32)'n') | ((u32)'d'<<8) | ((u32)' '<<16) | ((u32)'3'<<24);
+    input[2] = ((u32)'2') | ((u32)'-'<<8) | ((u32)'b'<<16) | ((u32)'y'<<24);
+    input[3] = ((u32)'t') | ((u32)'e'<<8) | ((u32)' '<<16) | ((u32)'k'<<24);
+
+    input[4] = key[0];
+    input[5] = key[1];
+    input[6] = key[2];
+    input[7] = key[3];
+    input[8] = key[4];
+    input[9] = key[5];
+    input[10] = key[6];
+    input[11] = key[7];
+
+    input[12] = counter[0];
+    input[13] = counter[1];
+    input[14] = counter[2];
+    input[15] = counter[3];
+
+    while (len > 0) {
+        todo = sizeof(buf);
+        if (len < todo)
+            todo = len;
+
+        chacha20_core(&buf, input);
+
+        for (i = 0; i < todo; i++)
+            out[i] = inp[i] ^ buf.c[i];
+        out += todo;
+        inp += todo;
+        len -= todo;
+
+        /* advance counter */
+        if (++input[12] == 0)
+            input[13]++;
+    }
+}