Include an IDEA implementation.

The code is the old IDEA test code, written by me back in 1997 and
distributed on a Danish FTP server.  This commit is only for
reference.  To use the code it has to be adjusted to the Libgcrypt
framework.

1 files changed, 476 insertions, 0 deletions

diff --git a/cipher/idea.c b/cipher/idea.c
new file mode 100644
index 00000000..65a8ec3a
--- /dev/null
+++ b/cipher/idea.c
@@ -0,0 +1,476 @@
+/* idea.c  -  IDEA function
+ *	Copyright (c) 1997, 1998, 1999, 2001 by Werner Koch (dd9jn)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * WERNER KOCH BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Werner Koch shall not be
+ * used in advertising or otherwise to promote the sale, use or other dealings
+ * in this Software without prior written authorization from Werner Koch.
+ *
+ * DUE TO PATENT CLAIMS THE DISTRIBUTION OF THE SOFTWARE IS NOT ALLOWED IN
+ * THESE COUNTRIES:
+ *     AUSTRIA, FRANCE, GERMANY, ITALY, JAPAN, THE NETHERLANDS,
+ *     SPAIN, SWEDEN, SWITZERLAND, THE UK AND THE US.
+ */
+
+/*
+ * Please see http://www.noepatents.org/ to learn why software patents
+ * are bad for society and what you can do to fight them.
+ *
+ * The code herein is based on the one from:
+ *   Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1996.
+ *    ISBN 0-471-11709-9. .
+ *
+ * How to compile:
+       gcc -Wall -O2 -shared -fPIC -o idea idea.c
+ *
+ * 2001-06-08 wk  Changed distribution conditions
+ * 2001-06-11 wk  Fixed invert_key (which is not used in CFB mode)
+ *                Thanks to Mark A. Borgerding.  Added defintion for
+ *                the PowerPC.
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+/* configuration stuff */
+#ifdef __alpha__
+  #define SIZEOF_UNSIGNED_LONG 8
+#else
+  #define SIZEOF_UNSIGNED_LONG 4
+#endif
+
+#if defined(__mc68000__) || defined (__sparc__) || defined (__PPC__) \
+    || (defined(__mips__) && (defined(MIPSEB) || defined (__MIPSEB__)) ) \
+    || defined(__powerpc__) \
+    || defined(__hpux__) /* should be replaced by the Macro for the PA */
+  #define BIG_ENDIAN_HOST 1
+#else
+  #define LITTLE_ENDIAN_HOST 1
+#endif
+
+typedef unsigned long  ulong;
+typedef unsigned short ushort;
+typedef unsigned char  byte;
+
+typedef unsigned short u16;
+typedef unsigned long  u32;
+
+/* end configurable stuff */
+
+#ifndef DIM
+  #define DIM(v) (sizeof(v)/sizeof((v)[0]))
+  #define DIMof(type,member)   DIM(((type *)0)->member)
+#endif
+
+/* imports */
+void g10_log_fatal( const char *fmt, ... );
+
+
+/* local stuff */
+
+#define FNCCAST_SETKEY(f)  ((int(*)(void*, byte*, unsigned))(f))
+#define FNCCAST_CRYPT(f)   ((void(*)(void*, byte*, byte*))(f))
+
+#define IDEA_KEYSIZE 16
+#define IDEA_BLOCKSIZE 8
+#define IDEA_ROUNDS 8
+#define IDEA_KEYLEN (6*IDEA_ROUNDS+4)
+
+typedef struct {
+    u16 ek[IDEA_KEYLEN];
+    u16 dk[IDEA_KEYLEN];
+    int have_dk;
+} IDEA_context;
+
+
+static int do_setkey( IDEA_context *c, byte *key, unsigned keylen );
+static void encrypt_block( IDEA_context *bc, byte *outbuf, byte *inbuf );
+static void decrypt_block( IDEA_context *bc, byte *outbuf, byte *inbuf );
+static void selftest(int);
+
+
+
+static u16
+mul_inv( u16 x )
+{
+    u16 t0, t1;
+    u16 q, y;
+
+    if( x < 2 )
+	return x;
+    t1 = 0x10001L / x;
+    y =  0x10001L % x;
+    if( y == 1 )
+	return (1-t1) & 0xffff;
+
+    t0 = 1;
+    do {
+	q = x / y;
+	x = x % y;
+	t0 += q * t1;
+	if( x == 1 )
+	    return t0;
+	q = y / x;
+	y = y % x;
+	t1 += q * t0;
+    } while( y != 1 );
+    return (1-t1) & 0xffff;
+}
+
+
+
+static void
+expand_key( byte *userkey, u16 *ek )
+{
+    int i,j;
+
+    for(j=0; j < 8; j++ ) {
+	ek[j] = (*userkey << 8) + userkey[1];
+	userkey += 2;
+    }
+    for(i=0; j < IDEA_KEYLEN; j++ ) {
+	i++;
+	ek[i+7] = ek[i&7] << 9 | ek[(i+1)&7] >> 7;
+	ek += i & 8;
+	i &= 7;
+    }
+}
+
+
+static void
+invert_key( u16 *ek, u16 dk[IDEA_KEYLEN] )
+{
+    int i;
+    u16 t1, t2, t3;
+    u16 temp[IDEA_KEYLEN];
+    u16 *p = temp + IDEA_KEYLEN;
+
+    t1 = mul_inv( *ek++ );
+    t2 = -*ek++;
+    t3 = -*ek++;
+    *--p = mul_inv( *ek++ );
+    *--p = t3;
+    *--p = t2;
+    *--p = t1;
+
+    for(i=0; i < IDEA_ROUNDS-1; i++ ) {
+	t1 = *ek++;
+	*--p = *ek++;
+	*--p = t1;
+
+	t1 = mul_inv( *ek++ );
+	t2 = -*ek++;
+	t3 = -*ek++;
+	*--p = mul_inv( *ek++ );
+	*--p = t2;
+	*--p = t3;
+	*--p = t1;
+    }
+    t1 = *ek++;
+    *--p = *ek++;
+    *--p = t1;
+
+    t1 = mul_inv( *ek++ );
+    t2 = -*ek++;
+    t3 = -*ek++;
+    *--p = mul_inv( *ek++ );
+    *--p = t3;
+    *--p = t2;
+    *--p = t1;
+    memcpy(dk, temp, sizeof(temp) );
+    memset(temp, 0, sizeof(temp) );  /* burn temp */
+}
+
+
+static void
+cipher( byte *outbuf, byte *inbuf, u16 *key )
+{
+    u16 x1, x2, x3,x4, s2, s3;
+    u16 *in, *out;
+    int r = IDEA_ROUNDS;
+  #define MUL(x,y) \
+	do {u16 _t16; u32 _t32; 		    \
+	    if( (_t16 = (y)) ) {		    \
+		if( (x = (x)&0xffff) ) {	    \
+		    _t32 = (u32)x * _t16;	    \
+		    x = _t32 & 0xffff;		    \
+		    _t16 = _t32 >> 16;		    \
+		    x = ((x)-_t16) + (x<_t16?1:0);  \
+		}				    \
+		else {				    \
+		    x = 1 - _t16;		    \
+		}				    \
+	    }					    \
+	    else {				    \
+		x = 1 - x;			    \
+	    }					    \
+	} while(0)
+
+    in = (u16*)inbuf;
+    x1 = *in++;
+    x2 = *in++;
+    x3 = *in++;
+    x4 = *in;
+  #ifdef LITTLE_ENDIAN_HOST
+    x1 = (x1>>8) | (x1<<8);
+    x2 = (x2>>8) | (x2<<8);
+    x3 = (x3>>8) | (x3<<8);
+    x4 = (x4>>8) | (x4<<8);
+  #endif
+    do {
+	MUL(x1, *key++);
+	x2 += *key++;
+	x3 += *key++;
+	MUL(x4, *key++ );
+
+	s3 = x3;
+	x3 ^= x1;
+	MUL(x3, *key++);
+	s2 = x2;
+	x2 ^=x4;
+	x2 += x3;
+	MUL(x2, *key++);
+	x3 += x2;
+
+	x1 ^= x2;
+	x4 ^= x3;
+
+	x2 ^= s3;
+	x3 ^= s2;
+    } while( --r );
+    MUL(x1, *key++);
+    x3 += *key++;
+    x2 += *key++;
+    MUL(x4, *key);
+
+    out = (u16*)outbuf;
+  #ifdef LITTLE_ENDIAN_HOST
+    *out++ = (x1>>8) | (x1<<8);
+    *out++ = (x3>>8) | (x3<<8);
+    *out++ = (x2>>8) | (x2<<8);
+    *out   = (x4>>8) | (x4<<8);
+  #else
+    *out++ = x1;
+    *out++ = x3;
+    *out++ = x2;
+    *out   = x4;
+  #endif
+  #undef MUL
+}
+
+
+static int
+do_setkey( IDEA_context *c, byte *key, unsigned keylen )
+{
+    static int initialized = 0;
+
+    if( !initialized ) {
+	initialized = 1;
+	selftest(0);
+    }
+    assert(keylen == 16);
+    c->have_dk = 0;
+    expand_key( key, c->ek );
+    invert_key( c->ek, c->dk );
+    return 0;
+}
+
+static void
+encrypt_block( IDEA_context *c, byte *outbuf, byte *inbuf )
+{
+    cipher( outbuf, inbuf, c->ek );
+}
+
+static void
+decrypt_block( IDEA_context *c, byte *outbuf, byte *inbuf )
+{
+    static int initialized;
+
+    if( !initialized ) {
+	initialized = 1;
+	selftest(1);
+    }
+    if( !c->have_dk ) {
+       c->have_dk = 1;
+       invert_key( c->ek, c->dk );
+    }
+    cipher( outbuf, inbuf, c->dk );
+}
+
+
+static void
+selftest( int check_decrypt )
+{
+static struct {
+    byte key[16];
+    byte plain[8];
+    byte cipher[8];
+} test_vectors[] = {
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0x00, 0x00, 0x00, 0x01, 0x00, 0x02, 0x00, 0x03 },
+      { 0x11, 0xFB, 0xED, 0x2B, 0x01, 0x98, 0x6D, 0xE5 } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 },
+      { 0x54, 0x0E, 0x5F, 0xEA, 0x18, 0xC2, 0xF8, 0xB1 } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0x00, 0x19, 0x32, 0x4B, 0x64, 0x7D, 0x96, 0xAF },
+      { 0x9F, 0x0A, 0x0A, 0xB6, 0xE1, 0x0C, 0xED, 0x78 } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0xF5, 0x20, 0x2D, 0x5B, 0x9C, 0x67, 0x1B, 0x08 },
+      { 0xCF, 0x18, 0xFD, 0x73, 0x55, 0xE2, 0xC5, 0xC5 } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0xFA, 0xE6, 0xD2, 0xBE, 0xAA, 0x96, 0x82, 0x6E },
+      { 0x85, 0xDF, 0x52, 0x00, 0x56, 0x08, 0x19, 0x3D } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0x0A, 0x14, 0x1E, 0x28, 0x32, 0x3C, 0x46, 0x50 },
+      { 0x2F, 0x7D, 0xE7, 0x50, 0x21, 0x2F, 0xB7, 0x34 } },
+    { { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+	0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 },
+      { 0x05, 0x0A, 0x0F, 0x14, 0x19, 0x1E, 0x23, 0x28 },
+      { 0x7B, 0x73, 0x14, 0x92, 0x5D, 0xE5, 0x9C, 0x09 } },
+    { { 0x00, 0x05, 0x00, 0x0A, 0x00, 0x0F, 0x00, 0x14,
+	0x00, 0x19, 0x00, 0x1E, 0x00, 0x23, 0x00, 0x28 },
+      { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 },
+      { 0x3E, 0xC0, 0x47, 0x80, 0xBE, 0xFF, 0x6E, 0x20 } },
+    { { 0x3A, 0x98, 0x4E, 0x20, 0x00, 0x19, 0x5D, 0xB3,
+	0x2E, 0xE5, 0x01, 0xC8, 0xC4, 0x7C, 0xEA, 0x60 },
+      { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 },
+      { 0x97, 0xBC, 0xD8, 0x20, 0x07, 0x80, 0xDA, 0x86 } },
+    { { 0x00, 0x64, 0x00, 0xC8, 0x01, 0x2C, 0x01, 0x90,
+	0x01, 0xF4, 0x02, 0x58, 0x02, 0xBC, 0x03, 0x20 },
+      { 0x05, 0x32, 0x0A, 0x64, 0x14, 0xC8, 0x19, 0xFA },
+      { 0x65, 0xBE, 0x87, 0xE7, 0xA2, 0x53, 0x8A, 0xED } },
+    { { 0x9D, 0x40, 0x75, 0xC1, 0x03, 0xBC, 0x32, 0x2A,
+	0xFB, 0x03, 0xE7, 0xBE, 0x6A, 0xB3, 0x00, 0x06 },
+      { 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08 },
+      { 0xF5, 0xDB, 0x1A, 0xC4, 0x5E, 0x5E, 0xF9, 0xF9 } }
+};
+    IDEA_context c;
+    byte buffer[8];
+    int i;
+
+    for(i=0; i < DIM(test_vectors); i++ ) {
+	do_setkey( &c, test_vectors[i].key, 16 );
+	if( !check_decrypt ) {
+	    encrypt_block( &c, buffer, test_vectors[i].plain );
+	    if( memcmp( buffer, test_vectors[i].cipher, 8 ) )
+		g10_log_fatal("idea encryption (%d) failed\n", i);
+	}
+	else {
+	    decrypt_block( &c, buffer, test_vectors[i].cipher );
+	    if( memcmp( buffer, test_vectors[i].plain, 8 ) )
+		g10_log_fatal("idea decryption (%d) failed\n", i);
+	}
+    }
+}
+
+
+/****************
+ * Return some information about the algorithm.  We need algo here to
+ * distinguish different flavors of the algorithm.
+ * Returns: A pointer to string describing the algorithm or NULL if
+ *	    the ALGO is invalid.
+ */
+const char *
+idea_get_info( int algo, size_t *keylen,
+		   size_t *blocksize, size_t *contextsize,
+		   int	(**r_setkey)( void *c, byte *key, unsigned keylen ),
+		   void (**r_encrypt)( void *c, byte *outbuf, byte *inbuf ),
+		   void (**r_decrypt)( void *c, byte *outbuf, byte *inbuf )
+		 )
+{
+    *keylen = 128;
+    *blocksize = 8;
+    *contextsize = sizeof(IDEA_context);
+    *r_setkey = FNCCAST_SETKEY(do_setkey);
+    *r_encrypt= FNCCAST_CRYPT(encrypt_block);
+    *r_decrypt= FNCCAST_CRYPT(decrypt_block);
+    if( algo == 1 )
+	return "IDEA";
+    return NULL;
+}
+
+
+
+const char * const gnupgext_version = "IDEA ($Revision: 1.11 $)";
+
+static struct {
+    int class;
+    int version;
+    int  value;
+    void (*func)(void);
+} func_table[] = {
+    { 20, 1, 0, (void(*)(void))idea_get_info },
+    { 21, 1, 1 },
+};
+
+
+
+/****************
+ * Enumerate the names of the functions together with informations about
+ * this function. Set sequence to an integer with a initial value of 0 and
+ * do not change it.
+ * If what is 0 all kind of functions are returned.
+ * Return values: class := class of function:
+ *			   10 = message digest algorithm info function
+ *			   11 = integer with available md algorithms
+ *			   20 = cipher algorithm info function
+ *			   21 = integer with available cipher algorithms
+ *			   30 = public key algorithm info function
+ *			   31 = integer with available pubkey algorithms
+ *		  version = interface version of the function/pointer
+ *			    (currently this is 1 for all functions)
+ */
+void *
+gnupgext_enum_func( int what, int *sequence, int *class, int *vers )
+{
+    void *ret;
+    int i = *sequence;
+
+    do {
+	if( i >= DIM(func_table) || i < 0 ) {
+	    return NULL;
+	}
+	*class = func_table[i].class;
+	*vers  = func_table[i].version;
+	switch( *class ) {
+	  case 11:
+	  case 21:
+	  case 31:
+	    ret = &func_table[i].value;
+	    break;
+	  default:
+	    ret = func_table[i].func;
+	    break;
+	}
+	i++;
+    } while( what && what != *class );
+
+    *sequence = i;
+    return ret;
+}