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authorAntonio Juarez <antonio.maria.juarez@live.com>2014-03-03 22:07:58 +0000
committerAntonio Juarez <antonio.maria.juarez@live.com>2014-03-03 22:07:58 +0000
commit296ae46ed8f8f6e5f986f978febad302e3df231a (patch)
tree1629164454a239308f33c9e12afb22e7f3cd8eeb /src/crypto/chacha8.c
parentchanged name (diff)
downloadmonero-296ae46ed8f8f6e5f986f978febad302e3df231a.tar.xz
moved all stuff to github
Diffstat (limited to 'src/crypto/chacha8.c')
-rw-r--r--src/crypto/chacha8.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/src/crypto/chacha8.c b/src/crypto/chacha8.c
new file mode 100644
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--- /dev/null
+++ b/src/crypto/chacha8.c
@@ -0,0 +1,170 @@
+/*
+chacha-merged.c version 20080118
+D. J. Bernstein
+Public domain.
+*/
+
+#include <memory.h>
+#include <stdio.h>
+#include <sys/param.h>
+
+#include "chacha8.h"
+#include "common/int-util.h"
+#include "warnings.h"
+
+/*
+ * The following macros are used to obtain exact-width results.
+ */
+#define U8V(v) ((uint8_t)(v) & UINT8_C(0xFF))
+#define U32V(v) ((uint32_t)(v) & UINT32_C(0xFFFFFFFF))
+
+/*
+ * The following macros load words from an array of bytes with
+ * different types of endianness, and vice versa.
+ */
+#define U8TO32_LITTLE(p) SWAP32LE(((uint32_t*)(p))[0])
+#define U32TO8_LITTLE(p, v) (((uint32_t*)(p))[0] = SWAP32LE(v))
+
+#define ROTATE(v,c) (rol32(v,c))
+#define XOR(v,w) ((v) ^ (w))
+#define PLUS(v,w) (U32V((v) + (w)))
+#define PLUSONE(v) (PLUS((v),1))
+
+#define QUARTERROUND(a,b,c,d) \
+ a = PLUS(a,b); d = ROTATE(XOR(d,a),16); \
+ c = PLUS(c,d); b = ROTATE(XOR(b,c),12); \
+ a = PLUS(a,b); d = ROTATE(XOR(d,a), 8); \
+ c = PLUS(c,d); b = ROTATE(XOR(b,c), 7);
+
+static const char sigma[] = "expand 32-byte k";
+
+DISABLE_GCC_AND_CLANG_WARNING(strict-aliasing)
+
+void chacha8(const void* data, size_t length, const uint8_t* key, const uint8_t* iv, char* cipher) {
+ uint32_t x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15;
+ uint32_t j0, j1, j2, j3, j4, j5, j6, j7, j8, j9, j10, j11, j12, j13, j14, j15;
+ char* ctarget = 0;
+ char tmp[64];
+ int i;
+
+ if (!length) return;
+
+ j0 = U8TO32_LITTLE(sigma + 0);
+ j1 = U8TO32_LITTLE(sigma + 4);
+ j2 = U8TO32_LITTLE(sigma + 8);
+ j3 = U8TO32_LITTLE(sigma + 12);
+ j4 = U8TO32_LITTLE(key + 0);
+ j5 = U8TO32_LITTLE(key + 4);
+ j6 = U8TO32_LITTLE(key + 8);
+ j7 = U8TO32_LITTLE(key + 12);
+ j8 = U8TO32_LITTLE(key + 16);
+ j9 = U8TO32_LITTLE(key + 20);
+ j10 = U8TO32_LITTLE(key + 24);
+ j11 = U8TO32_LITTLE(key + 28);
+ j12 = 0;
+ j13 = 0;
+ j14 = U8TO32_LITTLE(iv + 0);
+ j15 = U8TO32_LITTLE(iv + 4);
+
+ for (;;) {
+ if (length < 64) {
+ memcpy(tmp, data, length);
+ data = tmp;
+ ctarget = cipher;
+ cipher = tmp;
+ }
+ x0 = j0;
+ x1 = j1;
+ x2 = j2;
+ x3 = j3;
+ x4 = j4;
+ x5 = j5;
+ x6 = j6;
+ x7 = j7;
+ x8 = j8;
+ x9 = j9;
+ x10 = j10;
+ x11 = j11;
+ x12 = j12;
+ x13 = j13;
+ x14 = j14;
+ x15 = j15;
+ for (i = 8;i > 0;i -= 2) {
+ QUARTERROUND( x0, x4, x8,x12)
+ QUARTERROUND( x1, x5, x9,x13)
+ QUARTERROUND( x2, x6,x10,x14)
+ QUARTERROUND( x3, x7,x11,x15)
+ QUARTERROUND( x0, x5,x10,x15)
+ QUARTERROUND( x1, x6,x11,x12)
+ QUARTERROUND( x2, x7, x8,x13)
+ QUARTERROUND( x3, x4, x9,x14)
+ }
+ x0 = PLUS( x0, j0);
+ x1 = PLUS( x1, j1);
+ x2 = PLUS( x2, j2);
+ x3 = PLUS( x3, j3);
+ x4 = PLUS( x4, j4);
+ x5 = PLUS( x5, j5);
+ x6 = PLUS( x6, j6);
+ x7 = PLUS( x7, j7);
+ x8 = PLUS( x8, j8);
+ x9 = PLUS( x9, j9);
+ x10 = PLUS(x10,j10);
+ x11 = PLUS(x11,j11);
+ x12 = PLUS(x12,j12);
+ x13 = PLUS(x13,j13);
+ x14 = PLUS(x14,j14);
+ x15 = PLUS(x15,j15);
+
+ x0 = XOR( x0,U8TO32_LITTLE((uint8_t*)data + 0));
+ x1 = XOR( x1,U8TO32_LITTLE((uint8_t*)data + 4));
+ x2 = XOR( x2,U8TO32_LITTLE((uint8_t*)data + 8));
+ x3 = XOR( x3,U8TO32_LITTLE((uint8_t*)data + 12));
+ x4 = XOR( x4,U8TO32_LITTLE((uint8_t*)data + 16));
+ x5 = XOR( x5,U8TO32_LITTLE((uint8_t*)data + 20));
+ x6 = XOR( x6,U8TO32_LITTLE((uint8_t*)data + 24));
+ x7 = XOR( x7,U8TO32_LITTLE((uint8_t*)data + 28));
+ x8 = XOR( x8,U8TO32_LITTLE((uint8_t*)data + 32));
+ x9 = XOR( x9,U8TO32_LITTLE((uint8_t*)data + 36));
+ x10 = XOR(x10,U8TO32_LITTLE((uint8_t*)data + 40));
+ x11 = XOR(x11,U8TO32_LITTLE((uint8_t*)data + 44));
+ x12 = XOR(x12,U8TO32_LITTLE((uint8_t*)data + 48));
+ x13 = XOR(x13,U8TO32_LITTLE((uint8_t*)data + 52));
+ x14 = XOR(x14,U8TO32_LITTLE((uint8_t*)data + 56));
+ x15 = XOR(x15,U8TO32_LITTLE((uint8_t*)data + 60));
+
+ j12 = PLUSONE(j12);
+ if (!j12)
+ {
+ j13 = PLUSONE(j13);
+ /* stopping at 2^70 bytes per iv is user's responsibility */
+ }
+
+ U32TO8_LITTLE(cipher + 0,x0);
+ U32TO8_LITTLE(cipher + 4,x1);
+ U32TO8_LITTLE(cipher + 8,x2);
+ U32TO8_LITTLE(cipher + 12,x3);
+ U32TO8_LITTLE(cipher + 16,x4);
+ U32TO8_LITTLE(cipher + 20,x5);
+ U32TO8_LITTLE(cipher + 24,x6);
+ U32TO8_LITTLE(cipher + 28,x7);
+ U32TO8_LITTLE(cipher + 32,x8);
+ U32TO8_LITTLE(cipher + 36,x9);
+ U32TO8_LITTLE(cipher + 40,x10);
+ U32TO8_LITTLE(cipher + 44,x11);
+ U32TO8_LITTLE(cipher + 48,x12);
+ U32TO8_LITTLE(cipher + 52,x13);
+ U32TO8_LITTLE(cipher + 56,x14);
+ U32TO8_LITTLE(cipher + 60,x15);
+
+ if (length <= 64) {
+ if (length < 64) {
+ memcpy(ctarget, cipher, length);
+ }
+ return;
+ }
+ length -= 64;
+ cipher += 64;
+ data = (uint8_t*)data + 64;
+ }
+}