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authorWojtek Kosior <wk@koszkonutek-tmp.pl.eu.org>2021-04-30 00:33:56 +0200
committerWojtek Kosior <wk@koszkonutek-tmp.pl.eu.org>2021-04-30 00:33:56 +0200
commitaa4d426b4d3527d7e166df1a05058c9a4a0f6683 (patch)
tree4ff17ce8b89a2321b9d0ed4bcfc37c447bcb6820 /openssl-1.1.0h/crypto/chacha/chacha_enc.c
downloadsmtps-and-pop3s-console-program-master.tar.gz
smtps-and-pop3s-console-program-master.zip
initial/final commitHEADmaster
Diffstat (limited to 'openssl-1.1.0h/crypto/chacha/chacha_enc.c')
-rw-r--r--openssl-1.1.0h/crypto/chacha/chacha_enc.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/chacha/chacha_enc.c b/openssl-1.1.0h/crypto/chacha/chacha_enc.c
new file mode 100644
index 0000000..239f68a
--- /dev/null
+++ b/openssl-1.1.0h/crypto/chacha/chacha_enc.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+/* 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 32-bit counter. Note that as subroutine is so to
+ * say nonce-agnostic, this limited counter width doesn't
+ * prevent caller from implementing wider counter. It would
+ * simply take two calls split on counter overflow...
+ */
+ input[12]++;
+ }
+}