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-rw-r--r--security/nss/lib/freebl/chacha20.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/chacha20.c b/security/nss/lib/freebl/chacha20.c
new file mode 100644
index 000000000..f55d1e670
--- /dev/null
+++ b/security/nss/lib/freebl/chacha20.c
@@ -0,0 +1,119 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Adopted from the public domain code in NaCl by djb. */
+
+#include <string.h>
+#include <stdio.h>
+
+#include "prtypes.h"
+#include "secport.h"
+#include "chacha20.h"
+
+#if defined(_MSC_VER)
+#pragma intrinsic(_lrotl)
+#define ROTL32(x, n) _lrotl(x, n)
+#else
+#define ROTL32(x, n) ((x << n) | (x >> ((8 * sizeof x) - n)))
+#endif
+
+#define ROTATE(v, c) ROTL32((v), (c))
+
+#define U32TO8_LITTLE(p, v) \
+ { \
+ (p)[0] = ((v)) & 0xff; \
+ (p)[1] = ((v) >> 8) & 0xff; \
+ (p)[2] = ((v) >> 16) & 0xff; \
+ (p)[3] = ((v) >> 24) & 0xff; \
+ }
+#define U8TO32_LITTLE(p) \
+ (((PRUint32)((p)[0])) | ((PRUint32)((p)[1]) << 8) | \
+ ((PRUint32)((p)[2]) << 16) | ((PRUint32)((p)[3]) << 24))
+
+#define QUARTERROUND(x, a, b, c, d) \
+ x[a] = x[a] + x[b]; \
+ x[d] = ROTATE(x[d] ^ x[a], 16); \
+ x[c] = x[c] + x[d]; \
+ x[b] = ROTATE(x[b] ^ x[c], 12); \
+ x[a] = x[a] + x[b]; \
+ x[d] = ROTATE(x[d] ^ x[a], 8); \
+ x[c] = x[c] + x[d]; \
+ x[b] = ROTATE(x[b] ^ x[c], 7);
+
+static void
+ChaChaCore(unsigned char output[64], const PRUint32 input[16], int num_rounds)
+{
+ PRUint32 x[16];
+ int i;
+
+ PORT_Memcpy(x, input, sizeof(PRUint32) * 16);
+ for (i = num_rounds; i > 0; i -= 2) {
+ QUARTERROUND(x, 0, 4, 8, 12)
+ QUARTERROUND(x, 1, 5, 9, 13)
+ QUARTERROUND(x, 2, 6, 10, 14)
+ QUARTERROUND(x, 3, 7, 11, 15)
+ QUARTERROUND(x, 0, 5, 10, 15)
+ QUARTERROUND(x, 1, 6, 11, 12)
+ QUARTERROUND(x, 2, 7, 8, 13)
+ QUARTERROUND(x, 3, 4, 9, 14)
+ }
+
+ for (i = 0; i < 16; ++i) {
+ x[i] = x[i] + input[i];
+ }
+ for (i = 0; i < 16; ++i) {
+ U32TO8_LITTLE(output + 4 * i, x[i]);
+ }
+}
+
+static const unsigned char sigma[16] = "expand 32-byte k";
+
+void
+ChaCha20XOR(unsigned char *out, const unsigned char *in, unsigned int inLen,
+ const unsigned char key[32], const unsigned char nonce[12],
+ uint32_t counter)
+{
+ unsigned char block[64];
+ PRUint32 input[16];
+ unsigned int i;
+
+ 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[0] = U8TO32_LITTLE(sigma + 0);
+ input[1] = U8TO32_LITTLE(sigma + 4);
+ input[2] = U8TO32_LITTLE(sigma + 8);
+ input[3] = U8TO32_LITTLE(sigma + 12);
+
+ input[12] = counter;
+ input[13] = U8TO32_LITTLE(nonce + 0);
+ input[14] = U8TO32_LITTLE(nonce + 4);
+ input[15] = U8TO32_LITTLE(nonce + 8);
+
+ while (inLen >= 64) {
+ ChaChaCore(block, input, 20);
+ for (i = 0; i < 64; i++) {
+ out[i] = in[i] ^ block[i];
+ }
+
+ input[12]++;
+ inLen -= 64;
+ in += 64;
+ out += 64;
+ }
+
+ if (inLen > 0) {
+ ChaChaCore(block, input, 20);
+ for (i = 0; i < inLen; i++) {
+ out[i] = in[i] ^ block[i];
+ }
+ }
+}