third_party/openssl: add ChaCha20+Poly1305 support.

openssl/crypto/chacha/chacha_enc.c

+/*
+ *  Chacha stream algorithm.
+ *
+ *  Created on: Jun, 2013
+ *  Author: Elie Bursztein (elieb@google.com)
+ *
+ *  Adapted from the estream code by D. Bernstein.
+ */
+/* ====================================================================
+ * 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.
+ * ====================================================================
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <openssl/opensslconf.h>
+
+#if !defined(OPENSSL_NO_CHACHA)
+
+#include <openssl/crypto.h>
+#include <openssl/chacha.h>
+
+/* sigma contains the ChaCha constants, which happen to be an ASCII string. */
+static const char sigma[16] = "expand 32-byte k";
+
+#define ROTATE(v, n) (((v) << (n)) | ((v) >> (32 - (n))))
+#define XOR(v, w) ((v) ^ (w))
+#define PLUS(x, y) ((x) + (y))
+#define PLUSONE(v) (PLUS((v), 1))
+
+#define U32TO8_LITTLE(p, v) \
+        { (p)[0] = (v >>  0) & 0xff; (p)[1] = (v >>  8) & 0xff; \
+          (p)[2] = (v >> 16) & 0xff; (p)[3] = (v >> 24) & 0xff; }
+#define U8TO32_LITTLE(p)   \
+        (((uint32_t)((p)[0])      ) | ((uint32_t)((p)[1]) <<  8) | \
+         ((uint32_t)((p)[2]) << 16) | ((uint32_t)((p)[3]) << 24)   )
+
+/* QUARTERROUND updates a, b, c, d with a ChaCha "quarter" round. */
+#define QUARTERROUND(a,b,c,d) \
+  x[a] = PLUS(x[a],x[b]); x[d] = ROTATE(XOR(x[d],x[a]),16); \
+  x[c] = PLUS(x[c],x[d]); x[b] = ROTATE(XOR(x[b],x[c]),12); \
+  x[a] = PLUS(x[a],x[b]); x[d] = ROTATE(XOR(x[d],x[a]), 8); \
+  x[c] = PLUS(x[c],x[d]); x[b] = ROTATE(XOR(x[b],x[c]), 7);
+
+typedef unsigned int uint32_t;
+
+#if __arm__
+/* Defined in chacha_vec.c */
+void CRYPTO_chacha_20_neon(unsigned char *out,
+                           const unsigned char *in, size_t in_len,
+                           const unsigned char key[32],
+                           const unsigned char nonce[8],
+                           size_t counter);
+#endif
+
+/* chacha_core performs |num_rounds| rounds of ChaCha20 on the input words in
+ * |input| and writes the 64 output bytes to |output|. */
+static void chacha_core(unsigned char output[64], const uint32_t input[16],
+                        int num_rounds)
+        {
+        uint32_t x[16];
+        int i;
+
+        memcpy(x, input, sizeof(uint32_t) * 16);
+        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)
+                }
+
+        for (i = 0; i < 16; ++i)
+                x[i] = PLUS(x[i], input[i]);
+        for (i = 0; i < 16; ++i)
+                U32TO8_LITTLE(output + 4 * i, x[i]);
+        }
+
+void CRYPTO_chacha_20(unsigned char *out,
+                      const unsigned char *in, size_t in_len,
+                      const unsigned char key[32],
+                      const unsigned char nonce[8],
+                      size_t counter)
+        {
+        uint32_t input[16];
+        unsigned char buf[64];
+        size_t todo, i;
+
+#if __arm__
+        if (CRYPTO_is_NEON_capable())
+                {
+                CRYPTO_chacha_20_neon(out, in, in_len, key, nonce, counter);
+                return;
+                }
+#endif
+
+        input[0] = U8TO32_LITTLE(sigma + 0);
+        input[1] = U8TO32_LITTLE(sigma + 4);
+        input[2] = U8TO32_LITTLE(sigma + 8);
+        input[3] = U8TO32_LITTLE(sigma + 12);
+
+        input[4] = U8TO32_LITTLE(key + 0);
+        input[5] = U8TO32_LITTLE(key + 4);
+        input[6] = U8TO32_LITTLE(key + 8);
+        input[7] = U8TO32_LITTLE(key + 12);
+
+        input[8] = U8TO32_LITTLE(key + 16);
+        input[9] = U8TO32_LITTLE(key + 20);
+        input[10] = U8TO32_LITTLE(key + 24);
+        input[11] = U8TO32_LITTLE(key + 28);
+
+        input[12] = counter;
+        input[13] = ((uint64_t) counter) >> 32;
+        input[14] = U8TO32_LITTLE(nonce + 0);
+        input[15] = U8TO32_LITTLE(nonce + 4);
+
+        while (in_len > 0)
+                {
+                todo = sizeof(buf);
+                if (in_len < todo)
+                        todo = in_len;
+
+                chacha_core(buf, input, 20);
+                for (i = 0; i < todo; i++)
+                        out[i] = in[i] ^ buf[i];
+
+                out += todo;
+                in += todo;
+                in_len -= todo;
+
+                input[12]++;
+                if (input[12] == 0)
+                        input[13]++;
+                }
+        }
+
+#endif  /* !OPENSSL_NO_CHACHA */