freebsd-skq/sys/opencrypto/skipjack.c
jhb f2015b4065 Use 'const' for keys and IVs passed to software encryption algorithms.
Specifically, use 'const' for the key passed to the 'setkey' method
and 'const' for the 'iv' passed to the 'reinit' method.

Reviewed by:	cem
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D21347
2019-08-22 00:02:08 +00:00

261 lines
9.4 KiB
C

/* $OpenBSD: skipjack.c,v 1.3 2001/05/05 00:31:34 angelos Exp $ */
/*-
* Further optimized test implementation of SKIPJACK algorithm
* Mark Tillotson <markt@chaos.org.uk>, 25 June 98
* Optimizations suit RISC (lots of registers) machine best.
*
* based on unoptimized implementation of
* Panu Rissanen <bande@lut.fi> 960624
*
* SKIPJACK and KEA Algorithm Specifications
* Version 2.0
* 29 May 1998
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <opencrypto/skipjack.h>
static const u_int8_t ftable[0x100] =
{
0xa3, 0xd7, 0x09, 0x83, 0xf8, 0x48, 0xf6, 0xf4,
0xb3, 0x21, 0x15, 0x78, 0x99, 0xb1, 0xaf, 0xf9,
0xe7, 0x2d, 0x4d, 0x8a, 0xce, 0x4c, 0xca, 0x2e,
0x52, 0x95, 0xd9, 0x1e, 0x4e, 0x38, 0x44, 0x28,
0x0a, 0xdf, 0x02, 0xa0, 0x17, 0xf1, 0x60, 0x68,
0x12, 0xb7, 0x7a, 0xc3, 0xe9, 0xfa, 0x3d, 0x53,
0x96, 0x84, 0x6b, 0xba, 0xf2, 0x63, 0x9a, 0x19,
0x7c, 0xae, 0xe5, 0xf5, 0xf7, 0x16, 0x6a, 0xa2,
0x39, 0xb6, 0x7b, 0x0f, 0xc1, 0x93, 0x81, 0x1b,
0xee, 0xb4, 0x1a, 0xea, 0xd0, 0x91, 0x2f, 0xb8,
0x55, 0xb9, 0xda, 0x85, 0x3f, 0x41, 0xbf, 0xe0,
0x5a, 0x58, 0x80, 0x5f, 0x66, 0x0b, 0xd8, 0x90,
0x35, 0xd5, 0xc0, 0xa7, 0x33, 0x06, 0x65, 0x69,
0x45, 0x00, 0x94, 0x56, 0x6d, 0x98, 0x9b, 0x76,
0x97, 0xfc, 0xb2, 0xc2, 0xb0, 0xfe, 0xdb, 0x20,
0xe1, 0xeb, 0xd6, 0xe4, 0xdd, 0x47, 0x4a, 0x1d,
0x42, 0xed, 0x9e, 0x6e, 0x49, 0x3c, 0xcd, 0x43,
0x27, 0xd2, 0x07, 0xd4, 0xde, 0xc7, 0x67, 0x18,
0x89, 0xcb, 0x30, 0x1f, 0x8d, 0xc6, 0x8f, 0xaa,
0xc8, 0x74, 0xdc, 0xc9, 0x5d, 0x5c, 0x31, 0xa4,
0x70, 0x88, 0x61, 0x2c, 0x9f, 0x0d, 0x2b, 0x87,
0x50, 0x82, 0x54, 0x64, 0x26, 0x7d, 0x03, 0x40,
0x34, 0x4b, 0x1c, 0x73, 0xd1, 0xc4, 0xfd, 0x3b,
0xcc, 0xfb, 0x7f, 0xab, 0xe6, 0x3e, 0x5b, 0xa5,
0xad, 0x04, 0x23, 0x9c, 0x14, 0x51, 0x22, 0xf0,
0x29, 0x79, 0x71, 0x7e, 0xff, 0x8c, 0x0e, 0xe2,
0x0c, 0xef, 0xbc, 0x72, 0x75, 0x6f, 0x37, 0xa1,
0xec, 0xd3, 0x8e, 0x62, 0x8b, 0x86, 0x10, 0xe8,
0x08, 0x77, 0x11, 0xbe, 0x92, 0x4f, 0x24, 0xc5,
0x32, 0x36, 0x9d, 0xcf, 0xf3, 0xa6, 0xbb, 0xac,
0x5e, 0x6c, 0xa9, 0x13, 0x57, 0x25, 0xb5, 0xe3,
0xbd, 0xa8, 0x3a, 0x01, 0x05, 0x59, 0x2a, 0x46
};
/*
* For each key byte generate a table to represent the function
* ftable [in ^ keybyte]
*
* These tables used to save an XOR in each stage of the G-function
* the tables are hopefully pointed to by register allocated variables
* k0, k1..k9
*/
void
subkey_table_gen (const u_int8_t *key, u_int8_t **key_tables)
{
int i, k;
for (k = 0; k < 10; k++) {
u_int8_t key_byte = key [k];
u_int8_t * table = key_tables[k];
for (i = 0; i < 0x100; i++)
table [i] = ftable [i ^ key_byte];
}
}
#define g(k0, k1, k2, k3, ih, il, oh, ol) \
{ \
oh = k##k0 [il] ^ ih; \
ol = k##k1 [oh] ^ il; \
oh = k##k2 [ol] ^ oh; \
ol = k##k3 [oh] ^ ol; \
}
#define g0(ih, il, oh, ol) g(0, 1, 2, 3, ih, il, oh, ol)
#define g4(ih, il, oh, ol) g(4, 5, 6, 7, ih, il, oh, ol)
#define g8(ih, il, oh, ol) g(8, 9, 0, 1, ih, il, oh, ol)
#define g2(ih, il, oh, ol) g(2, 3, 4, 5, ih, il, oh, ol)
#define g6(ih, il, oh, ol) g(6, 7, 8, 9, ih, il, oh, ol)
#define g_inv(k0, k1, k2, k3, ih, il, oh, ol) \
{ \
ol = k##k3 [ih] ^ il; \
oh = k##k2 [ol] ^ ih; \
ol = k##k1 [oh] ^ ol; \
oh = k##k0 [ol] ^ oh; \
}
#define g0_inv(ih, il, oh, ol) g_inv(0, 1, 2, 3, ih, il, oh, ol)
#define g4_inv(ih, il, oh, ol) g_inv(4, 5, 6, 7, ih, il, oh, ol)
#define g8_inv(ih, il, oh, ol) g_inv(8, 9, 0, 1, ih, il, oh, ol)
#define g2_inv(ih, il, oh, ol) g_inv(2, 3, 4, 5, ih, il, oh, ol)
#define g6_inv(ih, il, oh, ol) g_inv(6, 7, 8, 9, ih, il, oh, ol)
/* optimized version of Skipjack algorithm
*
* the appropriate g-function is inlined for each round
*
* the data movement is minimized by rotating the names of the
* variables w1..w4, not their contents (saves 3 moves per round)
*
* the loops are completely unrolled (needed to staticize choice of g)
*
* compiles to about 470 instructions on a Sparc (gcc -O)
* which is about 58 instructions per byte, 14 per round.
* gcc seems to leave in some unnecessary and with 0xFF operations
* but only in the latter part of the functions. Perhaps it
* runs out of resources to properly optimize long inlined function?
* in theory should get about 11 instructions per round, not 14
*/
void
skipjack_forwards(u_int8_t *plain, u_int8_t *cipher, u_int8_t **key_tables)
{
u_int8_t wh1 = plain[0]; u_int8_t wl1 = plain[1];
u_int8_t wh2 = plain[2]; u_int8_t wl2 = plain[3];
u_int8_t wh3 = plain[4]; u_int8_t wl3 = plain[5];
u_int8_t wh4 = plain[6]; u_int8_t wl4 = plain[7];
u_int8_t * k0 = key_tables [0];
u_int8_t * k1 = key_tables [1];
u_int8_t * k2 = key_tables [2];
u_int8_t * k3 = key_tables [3];
u_int8_t * k4 = key_tables [4];
u_int8_t * k5 = key_tables [5];
u_int8_t * k6 = key_tables [6];
u_int8_t * k7 = key_tables [7];
u_int8_t * k8 = key_tables [8];
u_int8_t * k9 = key_tables [9];
/* first 8 rounds */
g0 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 1; wh4 ^= wh1;
g4 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 2; wh3 ^= wh4;
g8 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 3; wh2 ^= wh3;
g2 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 4; wh1 ^= wh2;
g6 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 5; wh4 ^= wh1;
g0 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 6; wh3 ^= wh4;
g4 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 7; wh2 ^= wh3;
g8 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 8; wh1 ^= wh2;
/* second 8 rounds */
wh2 ^= wh1; wl2 ^= wl1 ^ 9 ; g2 (wh1,wl1, wh1,wl1);
wh1 ^= wh4; wl1 ^= wl4 ^ 10; g6 (wh4,wl4, wh4,wl4);
wh4 ^= wh3; wl4 ^= wl3 ^ 11; g0 (wh3,wl3, wh3,wl3);
wh3 ^= wh2; wl3 ^= wl2 ^ 12; g4 (wh2,wl2, wh2,wl2);
wh2 ^= wh1; wl2 ^= wl1 ^ 13; g8 (wh1,wl1, wh1,wl1);
wh1 ^= wh4; wl1 ^= wl4 ^ 14; g2 (wh4,wl4, wh4,wl4);
wh4 ^= wh3; wl4 ^= wl3 ^ 15; g6 (wh3,wl3, wh3,wl3);
wh3 ^= wh2; wl3 ^= wl2 ^ 16; g0 (wh2,wl2, wh2,wl2);
/* third 8 rounds */
g4 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 17; wh4 ^= wh1;
g8 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 18; wh3 ^= wh4;
g2 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 19; wh2 ^= wh3;
g6 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 20; wh1 ^= wh2;
g0 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 21; wh4 ^= wh1;
g4 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 22; wh3 ^= wh4;
g8 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 23; wh2 ^= wh3;
g2 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 24; wh1 ^= wh2;
/* last 8 rounds */
wh2 ^= wh1; wl2 ^= wl1 ^ 25; g6 (wh1,wl1, wh1,wl1);
wh1 ^= wh4; wl1 ^= wl4 ^ 26; g0 (wh4,wl4, wh4,wl4);
wh4 ^= wh3; wl4 ^= wl3 ^ 27; g4 (wh3,wl3, wh3,wl3);
wh3 ^= wh2; wl3 ^= wl2 ^ 28; g8 (wh2,wl2, wh2,wl2);
wh2 ^= wh1; wl2 ^= wl1 ^ 29; g2 (wh1,wl1, wh1,wl1);
wh1 ^= wh4; wl1 ^= wl4 ^ 30; g6 (wh4,wl4, wh4,wl4);
wh4 ^= wh3; wl4 ^= wl3 ^ 31; g0 (wh3,wl3, wh3,wl3);
wh3 ^= wh2; wl3 ^= wl2 ^ 32; g4 (wh2,wl2, wh2,wl2);
/* pack into byte vector */
cipher [0] = wh1; cipher [1] = wl1;
cipher [2] = wh2; cipher [3] = wl2;
cipher [4] = wh3; cipher [5] = wl3;
cipher [6] = wh4; cipher [7] = wl4;
}
void
skipjack_backwards (u_int8_t *cipher, u_int8_t *plain, u_int8_t **key_tables)
{
/* setup 4 16-bit portions */
u_int8_t wh1 = cipher[0]; u_int8_t wl1 = cipher[1];
u_int8_t wh2 = cipher[2]; u_int8_t wl2 = cipher[3];
u_int8_t wh3 = cipher[4]; u_int8_t wl3 = cipher[5];
u_int8_t wh4 = cipher[6]; u_int8_t wl4 = cipher[7];
u_int8_t * k0 = key_tables [0];
u_int8_t * k1 = key_tables [1];
u_int8_t * k2 = key_tables [2];
u_int8_t * k3 = key_tables [3];
u_int8_t * k4 = key_tables [4];
u_int8_t * k5 = key_tables [5];
u_int8_t * k6 = key_tables [6];
u_int8_t * k7 = key_tables [7];
u_int8_t * k8 = key_tables [8];
u_int8_t * k9 = key_tables [9];
/* first 8 rounds */
g4_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 32; wh3 ^= wh2;
g0_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 31; wh4 ^= wh3;
g6_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 30; wh1 ^= wh4;
g2_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 29; wh2 ^= wh1;
g8_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 28; wh3 ^= wh2;
g4_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 27; wh4 ^= wh3;
g0_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 26; wh1 ^= wh4;
g6_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 25; wh2 ^= wh1;
/* second 8 rounds */
wh1 ^= wh2; wl1 ^= wl2 ^ 24; g2_inv (wh2,wl2, wh2,wl2);
wh2 ^= wh3; wl2 ^= wl3 ^ 23; g8_inv (wh3,wl3, wh3,wl3);
wh3 ^= wh4; wl3 ^= wl4 ^ 22; g4_inv (wh4,wl4, wh4,wl4);
wh4 ^= wh1; wl4 ^= wl1 ^ 21; g0_inv (wh1,wl1, wh1,wl1);
wh1 ^= wh2; wl1 ^= wl2 ^ 20; g6_inv (wh2,wl2, wh2,wl2);
wh2 ^= wh3; wl2 ^= wl3 ^ 19; g2_inv (wh3,wl3, wh3,wl3);
wh3 ^= wh4; wl3 ^= wl4 ^ 18; g8_inv (wh4,wl4, wh4,wl4);
wh4 ^= wh1; wl4 ^= wl1 ^ 17; g4_inv (wh1,wl1, wh1,wl1);
/* third 8 rounds */
g0_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 16; wh3 ^= wh2;
g6_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 15; wh4 ^= wh3;
g2_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 14; wh1 ^= wh4;
g8_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 13; wh2 ^= wh1;
g4_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 12; wh3 ^= wh2;
g0_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 11; wh4 ^= wh3;
g6_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 10; wh1 ^= wh4;
g2_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 9; wh2 ^= wh1;
/* last 8 rounds */
wh1 ^= wh2; wl1 ^= wl2 ^ 8; g8_inv (wh2,wl2, wh2,wl2);
wh2 ^= wh3; wl2 ^= wl3 ^ 7; g4_inv (wh3,wl3, wh3,wl3);
wh3 ^= wh4; wl3 ^= wl4 ^ 6; g0_inv (wh4,wl4, wh4,wl4);
wh4 ^= wh1; wl4 ^= wl1 ^ 5; g6_inv (wh1,wl1, wh1,wl1);
wh1 ^= wh2; wl1 ^= wl2 ^ 4; g2_inv (wh2,wl2, wh2,wl2);
wh2 ^= wh3; wl2 ^= wl3 ^ 3; g8_inv (wh3,wl3, wh3,wl3);
wh3 ^= wh4; wl3 ^= wl4 ^ 2; g4_inv (wh4,wl4, wh4,wl4);
wh4 ^= wh1; wl4 ^= wl1 ^ 1; g0_inv (wh1,wl1, wh1,wl1);
/* pack into byte vector */
plain [0] = wh1; plain [1] = wl1;
plain [2] = wh2; plain [3] = wl2;
plain [4] = wh3; plain [5] = wl3;
plain [6] = wh4; plain [7] = wl4;
}