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gerrit-public.fairphone.software / platform / external / openssh / 48bd7c118a25b950842864c7eb87ef666cbc342d / . / rijndael.c
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/* $OpenBSD: rijndael.c,v 1.6 2000/12/09 13:48:31 markus Exp $ */
/* This is an independent implementation of the encryption algorithm: */
/* */
/* RIJNDAEL by Joan Daemen and Vincent Rijmen */
/* */
/* which is a candidate algorithm in the Advanced Encryption Standard */
/* programme of the US National Institute of Standards and Technology. */
/* */
/* Copyright in this implementation is held by Dr B R Gladman but I */
/* hereby give permission for its free direct or derivative use subject */
/* to acknowledgment of its origin and compliance with any conditions */
/* that the originators of the algorithm place on its exploitation. */
/* */
/* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999 */
/* Timing data for Rijndael (rijndael.c)
Algorithm: rijndael (rijndael.c)
128 bit key:
Key Setup: 305/1389 cycles (encrypt/decrypt)
Encrypt: 374 cycles = 68.4 mbits/sec
Decrypt: 352 cycles = 72.7 mbits/sec
Mean: 363 cycles = 70.5 mbits/sec
192 bit key:
Key Setup: 277/1595 cycles (encrypt/decrypt)
Encrypt: 439 cycles = 58.3 mbits/sec
Decrypt: 425 cycles = 60.2 mbits/sec
Mean: 432 cycles = 59.3 mbits/sec
256 bit key:
Key Setup: 374/1960 cycles (encrypt/decrypt)
Encrypt: 502 cycles = 51.0 mbits/sec
Decrypt: 498 cycles = 51.4 mbits/sec
Mean: 500 cycles = 51.2 mbits/sec
*/
#include "config.h"
#include "rijndael.h"
void gen_tabs __P((void));
/* 3. Basic macros for speeding up generic operations */
/* Circular rotate of 32 bit values */
#define rotr(x,n) (((x) >> ((int)(n))) | ((x) << (32 - (int)(n))))
#define rotl(x,n) (((x) << ((int)(n))) | ((x) >> (32 - (int)(n))))
/* Invert byte order in a 32 bit variable */
#define bswap(x) ((rotl(x, 8) & 0x00ff00ff) | (rotr(x, 8) & 0xff00ff00))
/* Extract byte from a 32 bit quantity (little endian notation) */
#define byte(x,n) ((u1byte)((x) >> (8 * n)))
#if BYTE_ORDER != LITTLE_ENDIAN
#define BYTE_SWAP
#endif
#ifdef BYTE_SWAP
#define io_swap(x) bswap(x)
#else
#define io_swap(x) (x)
#endif
#define LARGE_TABLES
u1byte pow_tab[256];
u1byte log_tab[256];
u1byte sbx_tab[256];
u1byte isb_tab[256];
u4byte rco_tab[ 10];
u4byte ft_tab[4][256];
u4byte it_tab[4][256];
#ifdef LARGE_TABLES
u4byte fl_tab[4][256];
u4byte il_tab[4][256];
#endif
u4byte tab_gen = 0;
#define ff_mult(a,b) (a && b ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 0)
#define f_rn(bo, bi, n, k) \
bo[n] = ft_tab[0][byte(bi[n],0)] ^ \
ft_tab[1][byte(bi[(n + 1) & 3],1)] ^ \
ft_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
ft_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
#define i_rn(bo, bi, n, k) \
bo[n] = it_tab[0][byte(bi[n],0)] ^ \
it_tab[1][byte(bi[(n + 3) & 3],1)] ^ \
it_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
it_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
#ifdef LARGE_TABLES
#define ls_box(x) \
( fl_tab[0][byte(x, 0)] ^ \
fl_tab[1][byte(x, 1)] ^ \
fl_tab[2][byte(x, 2)] ^ \
fl_tab[3][byte(x, 3)] )
#define f_rl(bo, bi, n, k) \
bo[n] = fl_tab[0][byte(bi[n],0)] ^ \
fl_tab[1][byte(bi[(n + 1) & 3],1)] ^ \
fl_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
fl_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
#define i_rl(bo, bi, n, k) \
bo[n] = il_tab[0][byte(bi[n],0)] ^ \
il_tab[1][byte(bi[(n + 3) & 3],1)] ^ \
il_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
il_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
#else
#define ls_box(x) \
((u4byte)sbx_tab[byte(x, 0)] << 0) ^ \
((u4byte)sbx_tab[byte(x, 1)] << 8) ^ \
((u4byte)sbx_tab[byte(x, 2)] << 16) ^ \
((u4byte)sbx_tab[byte(x, 3)] << 24)
#define f_rl(bo, bi, n, k) \
bo[n] = (u4byte)sbx_tab[byte(bi[n],0)] ^ \
rotl(((u4byte)sbx_tab[byte(bi[(n + 1) & 3],1)]), 8) ^ \
rotl(((u4byte)sbx_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \
rotl(((u4byte)sbx_tab[byte(bi[(n + 3) & 3],3)]), 24) ^ *(k + n)
#define i_rl(bo, bi, n, k) \
bo[n] = (u4byte)isb_tab[byte(bi[n],0)] ^ \
rotl(((u4byte)isb_tab[byte(bi[(n + 3) & 3],1)]), 8) ^ \
rotl(((u4byte)isb_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \
rotl(((u4byte)isb_tab[byte(bi[(n + 1) & 3],3)]), 24) ^ *(k + n)
#endif
void
gen_tabs(void)
{
u4byte i, t;
u1byte p, q;
/* log and power tables for GF(2**8) finite field with */
/* 0x11b as modular polynomial - the simplest prmitive */
/* root is 0x11, used here to generate the tables */
for(i = 0,p = 1; i < 256; ++i) {
pow_tab[i] = (u1byte)p; log_tab[p] = (u1byte)i;
p = p ^ (p << 1) ^ (p & 0x80 ? 0x01b : 0);
}
log_tab[1] = 0; p = 1;
for(i = 0; i < 10; ++i) {
rco_tab[i] = p;
p = (p << 1) ^ (p & 0x80 ? 0x1b : 0);
}
/* note that the affine byte transformation matrix in */
/* rijndael specification is in big endian format with */
/* bit 0 as the most significant bit. In the remainder */
/* of the specification the bits are numbered from the */
/* least significant end of a byte. */
for(i = 0; i < 256; ++i) {
p = (i ? pow_tab[255 - log_tab[i]] : 0); q = p;
q = (q >> 7) | (q << 1); p ^= q;
q = (q >> 7) | (q << 1); p ^= q;
q = (q >> 7) | (q << 1); p ^= q;
q = (q >> 7) | (q << 1); p ^= q ^ 0x63;
sbx_tab[i] = (u1byte)p; isb_tab[p] = (u1byte)i;
}
for(i = 0; i < 256; ++i) {
p = sbx_tab[i];
#ifdef LARGE_TABLES
t = p; fl_tab[0][i] = t;
fl_tab[1][i] = rotl(t, 8);
fl_tab[2][i] = rotl(t, 16);
fl_tab[3][i] = rotl(t, 24);
#endif
t = ((u4byte)ff_mult(2, p)) |
((u4byte)p << 8) |
((u4byte)p << 16) |
((u4byte)ff_mult(3, p) << 24);
ft_tab[0][i] = t;
ft_tab[1][i] = rotl(t, 8);
ft_tab[2][i] = rotl(t, 16);
ft_tab[3][i] = rotl(t, 24);
p = isb_tab[i];
#ifdef LARGE_TABLES
t = p; il_tab[0][i] = t;
il_tab[1][i] = rotl(t, 8);
il_tab[2][i] = rotl(t, 16);
il_tab[3][i] = rotl(t, 24);
#endif
t = ((u4byte)ff_mult(14, p)) |
((u4byte)ff_mult( 9, p) << 8) |
((u4byte)ff_mult(13, p) << 16) |
((u4byte)ff_mult(11, p) << 24);
it_tab[0][i] = t;
it_tab[1][i] = rotl(t, 8);
it_tab[2][i] = rotl(t, 16);
it_tab[3][i] = rotl(t, 24);
}
tab_gen = 1;
}
#define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 0x1b)
#define imix_col(y,x) \
u = star_x(x); \
v = star_x(u); \
w = star_x(v); \
t = w ^ (x); \
(y) = u ^ v ^ w; \
(y) ^= rotr(u ^ t, 8) ^ \
rotr(v ^ t, 16) ^ \
rotr(t,24)
/* initialise the key schedule from the user supplied key */
#define loop4(i) \
{ t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \
t ^= e_key[4 * i]; e_key[4 * i + 4] = t; \
t ^= e_key[4 * i + 1]; e_key[4 * i + 5] = t; \
t ^= e_key[4 * i + 2]; e_key[4 * i + 6] = t; \
t ^= e_key[4 * i + 3]; e_key[4 * i + 7] = t; \
}
#define loop6(i) \
{ t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \
t ^= e_key[6 * i]; e_key[6 * i + 6] = t; \
t ^= e_key[6 * i + 1]; e_key[6 * i + 7] = t; \
t ^= e_key[6 * i + 2]; e_key[6 * i + 8] = t; \
t ^= e_key[6 * i + 3]; e_key[6 * i + 9] = t; \
t ^= e_key[6 * i + 4]; e_key[6 * i + 10] = t; \
t ^= e_key[6 * i + 5]; e_key[6 * i + 11] = t; \
}
#define loop8(i) \
{ t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \
t ^= e_key[8 * i]; e_key[8 * i + 8] = t; \
t ^= e_key[8 * i + 1]; e_key[8 * i + 9] = t; \
t ^= e_key[8 * i + 2]; e_key[8 * i + 10] = t; \
t ^= e_key[8 * i + 3]; e_key[8 * i + 11] = t; \
t = e_key[8 * i + 4] ^ ls_box(t); \
e_key[8 * i + 12] = t; \
t ^= e_key[8 * i + 5]; e_key[8 * i + 13] = t; \
t ^= e_key[8 * i + 6]; e_key[8 * i + 14] = t; \
t ^= e_key[8 * i + 7]; e_key[8 * i + 15] = t; \
}
rijndael_ctx *
rijndael_set_key(rijndael_ctx *ctx, const u4byte *in_key, const u4byte key_len,
int encrypt)
{
u4byte i, t, u, v, w;
u4byte *e_key = ctx->e_key;
u4byte *d_key = ctx->d_key;
ctx->decrypt = !encrypt;
if(!tab_gen)
gen_tabs();
ctx->k_len = (key_len + 31) / 32;
e_key[0] = io_swap(in_key[0]); e_key[1] = io_swap(in_key[1]);
e_key[2] = io_swap(in_key[2]); e_key[3] = io_swap(in_key[3]);
switch(ctx->k_len) {
case 4: t = e_key[3];
for(i = 0; i < 10; ++i)
loop4(i);
break;
case 6: e_key[4] = io_swap(in_key[4]); t = e_key[5] = io_swap(in_key[5]);
for(i = 0; i < 8; ++i)
loop6(i);
break;
case 8: e_key[4] = io_swap(in_key[4]); e_key[5] = io_swap(in_key[5]);
e_key[6] = io_swap(in_key[6]); t = e_key[7] = io_swap(in_key[7]);
for(i = 0; i < 7; ++i)
loop8(i);
break;
}
if (!encrypt) {
d_key[0] = e_key[0]; d_key[1] = e_key[1];
d_key[2] = e_key[2]; d_key[3] = e_key[3];
for(i = 4; i < 4 * ctx->k_len + 24; ++i) {
imix_col(d_key[i], e_key[i]);
}
}
return ctx;
}
/* encrypt a block of text */
#define f_nround(bo, bi, k) \
f_rn(bo, bi, 0, k); \
f_rn(bo, bi, 1, k); \
f_rn(bo, bi, 2, k); \
f_rn(bo, bi, 3, k); \
k += 4
#define f_lround(bo, bi, k) \
f_rl(bo, bi, 0, k); \
f_rl(bo, bi, 1, k); \
f_rl(bo, bi, 2, k); \
f_rl(bo, bi, 3, k)
void
rijndael_encrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
{
u4byte k_len = ctx->k_len;
u4byte *e_key = ctx->e_key;
u4byte b0[4], b1[4], *kp;
b0[0] = io_swap(in_blk[0]) ^ e_key[0];
b0[1] = io_swap(in_blk[1]) ^ e_key[1];
b0[2] = io_swap(in_blk[2]) ^ e_key[2];
b0[3] = io_swap(in_blk[3]) ^ e_key[3];
kp = e_key + 4;
if(k_len > 6) {
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
}
if(k_len > 4) {
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
}
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_lround(b0, b1, kp);
out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]);
out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]);
}
/* decrypt a block of text */
#define i_nround(bo, bi, k) \
i_rn(bo, bi, 0, k); \
i_rn(bo, bi, 1, k); \
i_rn(bo, bi, 2, k); \
i_rn(bo, bi, 3, k); \
k -= 4
#define i_lround(bo, bi, k) \
i_rl(bo, bi, 0, k); \
i_rl(bo, bi, 1, k); \
i_rl(bo, bi, 2, k); \
i_rl(bo, bi, 3, k)
void
rijndael_decrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
{
u4byte b0[4], b1[4], *kp;
u4byte k_len = ctx->k_len;
u4byte *e_key = ctx->e_key;
u4byte *d_key = ctx->d_key;
b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24];
b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25];
b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26];
b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27];
kp = d_key + 4 * (k_len + 5);
if(k_len > 6) {
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
if(k_len > 4) {
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_lround(b0, b1, kp);
out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]);
out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]);
}