[project @ akuchling-20020516233050-85ce258c1e144af3]

[project @ 2002-05-16 16:30:50 by akuchling]
Move C implementation files into src/

1 files changed, 184 insertions, 0 deletions

diff --git a/src/ARC2.c b/src/ARC2.c
new file mode 100644
index 0000000..12c668e
--- /dev/null
+++ b/src/ARC2.c
@@ -0,0 +1,184 @@
+
+/*
+ *  rc2.c : Source code for the RC2 block cipher
+ *
+ * Part of the Python Cryptography Toolkit
+ *
+ * Distribute and use freely; there are no restrictions on further 
+ * dissemination and usage except those imposed by the laws of your 
+ * country of residence.
+ *
+ */
+  
+
+#define MODULE_NAME ARC2
+#define BLOCK_SIZE 8
+#define KEY_SIZE 0
+
+typedef unsigned int U32;
+typedef unsigned short U16;
+typedef unsigned char U8;
+
+typedef struct 
+{
+ U16 xkey[64];
+} block_state;
+
+static void
+block_encrypt(block_state *self, U8 *in, U8 *out)
+{
+  U16 x76, x54, x32, x10;
+  int i;
+  
+  x76 = (in[7] << 8) + in[6];
+  x54 = (in[5] << 8) + in[4];
+  x32 = (in[3] << 8) + in[2];
+  x10 = (in[1] << 8) + in[0];
+  
+  for (i = 0; i < 16; i++)
+    {
+      x10 += (x32 & ~x76) + (x54 & x76) + self->xkey[4*i+0];
+      x10 = (x10 << 1) + (x10 >> 15 & 1);
+      
+      x32 += (x54 & ~x10) + (x76 & x10) + self->xkey[4*i+1];
+      x32 = (x32 << 2) + (x32 >> 14 & 3);
+      
+      x54 += (x76 & ~x32) + (x10 & x32) + self->xkey[4*i+2];
+      x54 = (x54 << 3) + (x54 >> 13 & 7);
+      
+      x76 += (x10 & ~x54) + (x32 & x54) + self->xkey[4*i+3];
+      x76 = (x76 << 5) + (x76 >> 11 & 31);
+      
+      if (i == 4 || i == 10) {
+	x10 += self->xkey[x76 & 63];
+	x32 += self->xkey[x10 & 63];
+	x54 += self->xkey[x32 & 63];
+	x76 += self->xkey[x54 & 63];
+      }
+    }
+  
+  out[0] = (U8)x10;
+  out[1] = (U8)(x10 >> 8);
+  out[2] = (U8)x32;
+  out[3] = (U8)(x32 >> 8);
+  out[4] = (U8)x54;
+  out[5] = (U8)(x54 >> 8);
+  out[6] = (U8)x76;
+  out[7] = (U8)(x76 >> 8);
+}
+
+
+static void
+block_decrypt(block_state *self, U8 *in, U8 *out)
+{
+  U16 x76, x54, x32, x10;
+  int i;
+  
+  x76 = (in[7] << 8) + in[6];
+  x54 = (in[5] << 8) + in[4];
+  x32 = (in[3] << 8) + in[2];
+  x10 = (in[1] << 8) + in[0];
+  
+  i = 15;
+  do {
+    x76 &= 65535;
+    x76 = (x76 << 11) + (x76 >> 5);
+    x76 -= (x10 & ~x54) + (x32 & x54) + self->xkey[4*i+3];
+    
+    x54 &= 65535;
+    x54 = (x54 << 13) + (x54 >> 3);
+    x54 -= (x76 & ~x32) + (x10 & x32) + self->xkey[4*i+2];
+    
+    x32 &= 65535;
+    x32 = (x32 << 14) + (x32 >> 2);
+    x32 -= (x54 & ~x10) + (x76 & x10) + self->xkey[4*i+1];
+    
+    x10 &= 65535;
+    x10 = (x10 << 15) + (x10 >> 1);
+    x10 -= (x32 & ~x76) + (x54 & x76) + self->xkey[4*i+0];
+    
+    if (i == 5 || i == 11) {
+      x76 -= self->xkey[x54 & 63];
+      x54 -= self->xkey[x32 & 63];
+      x32 -= self->xkey[x10 & 63];
+      x10 -= self->xkey[x76 & 63];
+    }
+  } while (i--);
+  
+  out[0] = (U8)x10;
+  out[1] = (U8)(x10 >> 8);
+  out[2] = (U8)x32;
+  out[3] = (U8)(x32 >> 8);
+  out[4] = (U8)x54;
+  out[5] = (U8)(x54 >> 8);
+  out[6] = (U8)x76;
+  out[7] = (U8)(x76 >> 8);
+}
+
+
+static void 
+block_init(block_state *self, U8 *key, int keylength)
+{
+  U8 x;
+  U16 i;
+        /* 256-entry permutation table, probably derived somehow from pi */
+        static const U8 permute[256] = {
+            217,120,249,196, 25,221,181,237, 40,233,253,121, 74,160,216,157,
+            198,126, 55,131, 43,118, 83,142, 98, 76,100,136, 68,139,251,162,
+             23,154, 89,245,135,179, 79, 19, 97, 69,109,141,  9,129,125, 50,
+            189,143, 64,235,134,183,123, 11,240,149, 33, 34, 92,107, 78,130,
+             84,214,101,147,206, 96,178, 28,115, 86,192, 20,167,140,241,220,
+             18,117,202, 31, 59,190,228,209, 66, 61,212, 48,163, 60,182, 38,
+            111,191, 14,218, 70,105,  7, 87, 39,242, 29,155,188,148, 67,  3,
+            248, 17,199,246,144,239, 62,231,  6,195,213, 47,200,102, 30,215,
+              8,232,234,222,128, 82,238,247,132,170,114,172, 53, 77,106, 42,
+            150, 26,210,113, 90, 21, 73,116, 75,159,208, 94,  4, 24,164,236,
+            194,224, 65,110, 15, 81,203,204, 36,145,175, 80,161,244,112, 57,
+            153,124, 58,133, 35,184,180,122,252,  2, 54, 91, 37, 85,151, 49,
+             45, 93,250,152,227,138,146,174,  5,223, 41, 16,103,108,186,201,
+            211,  0,230,207,225,158,168, 44, 99, 22,  1, 63, 88,226,137,169,
+             13, 56, 52, 27,171, 51,255,176,187, 72, 12, 95,185,177,205, 46,
+            197,243,219, 71,229,165,156,119, 10,166, 32,104,254,127,193,173
+        };
+
+  /* The "bits" value may be some sort of export control weakening.
+     We'll hardwire it to 1024. */
+#define bits 1024
+
+  memcpy(self->xkey, key, keylength);
+  
+  /* Phase 1: Expand input key to 128 bytes */
+  if (keylength < 128) {
+    i = 0;
+    x = ((U8 *)self->xkey)[keylength-1];
+                do {
+		  x = permute[(x + ((U8 *)self->xkey)[i++]) & 255];
+                        ((U8 *)self->xkey)[keylength++] = x;
+                } while (keylength < 128);
+  }
+  
+  /* Phase 2 - reduce effective key size to "bits" */
+  keylength = (bits+7) >> 3;
+  i = 128-keylength;
+  x = permute[((U8 *)self->xkey)[i] & (255 >>
+				 (7 &
+				  ((bits %8 ) ? 8-(bits%8): 0))
+				 )];
+  ((U8 *)self->xkey)[i] = x;
+  
+  while (i--) {
+    x = permute[ x ^ ((U8 *)self->xkey)[i+keylength] ];
+    ((U8 *)self->xkey)[i] = x;
+        }
+  
+  /* Phase 3 - copy to self->xkey in little-endian order */
+  i = 63;
+  do {
+    self->xkey[i] =  ((U8 *)self->xkey)[2*i] +
+      (((U8 *)self->xkey)[2*i+1] << 8);
+  } while (i--);
+}
+
+#undef bits
+
+#include "block_template.c"