root/crypto/serpent_generic.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Cryptographic API.
 *
 * Serpent Cipher Algorithm.
 *
 * Copyright (C) 2002 Dag Arne Osvik <osvik@ii.uib.no>
 */

#include <crypto/algapi.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/unaligned.h>
#include <linux/types.h>
#include <crypto/serpent.h>

/* Key is padded to the maximum of 256 bits before round key generation.
 * Any key length <= 256 bits (32 bytes) is allowed by the algorithm.
 */

#define PHI 0x9e3779b9UL

#define keyiter(a, b, c, d, i, j) \
        ({ b ^= d; b ^= c; b ^= a; b ^= PHI ^ i; b = rol32(b, 11); k[j] = b; })

#define loadkeys(x0, x1, x2, x3, i) \
        ({ x0 = k[i]; x1 = k[i+1]; x2 = k[i+2]; x3 = k[i+3]; })

#define storekeys(x0, x1, x2, x3, i) \
        ({ k[i] = x0; k[i+1] = x1; k[i+2] = x2; k[i+3] = x3; })

#define store_and_load_keys(x0, x1, x2, x3, s, l) \
        ({ storekeys(x0, x1, x2, x3, s); loadkeys(x0, x1, x2, x3, l); })

#define K(x0, x1, x2, x3, i) ({                         \
        x3 ^= k[4*(i)+3];        x2 ^= k[4*(i)+2];      \
        x1 ^= k[4*(i)+1];        x0 ^= k[4*(i)+0];      \
        })

#define LK(x0, x1, x2, x3, x4, i) ({                                       \
                                                        x0 = rol32(x0, 13);\
        x2 = rol32(x2, 3);      x1 ^= x0;               x4  = x0 << 3;     \
        x3 ^= x2;               x1 ^= x2;                                  \
        x1 = rol32(x1, 1);      x3 ^= x4;                                  \
        x3 = rol32(x3, 7);      x4  = x1;                                  \
        x0 ^= x1;               x4 <<= 7;               x2 ^= x3;          \
        x0 ^= x3;               x2 ^= x4;               x3 ^= k[4*i+3];    \
        x1 ^= k[4*i+1];         x0 = rol32(x0, 5);      x2 = rol32(x2, 22);\
        x0 ^= k[4*i+0];         x2 ^= k[4*i+2];                            \
        })

#define KL(x0, x1, x2, x3, x4, i) ({                                       \
        x0 ^= k[4*i+0];         x1 ^= k[4*i+1];         x2 ^= k[4*i+2];    \
        x3 ^= k[4*i+3];         x0 = ror32(x0, 5);      x2 = ror32(x2, 22);\
        x4 =  x1;               x2 ^= x3;               x0 ^= x3;          \
        x4 <<= 7;               x0 ^= x1;               x1 = ror32(x1, 1); \
        x2 ^= x4;               x3 = ror32(x3, 7);      x4 = x0 << 3;      \
        x1 ^= x0;               x3 ^= x4;               x0 = ror32(x0, 13);\
        x1 ^= x2;               x3 ^= x2;               x2 = ror32(x2, 3); \
        })

#define S0(x0, x1, x2, x3, x4) ({                       \
                                        x4  = x3;       \
        x3 |= x0;       x0 ^= x4;       x4 ^= x2;       \
        x4 = ~x4;       x3 ^= x1;       x1 &= x0;       \
        x1 ^= x4;       x2 ^= x0;       x0 ^= x3;       \
        x4 |= x0;       x0 ^= x2;       x2 &= x1;       \
        x3 ^= x2;       x1 = ~x1;       x2 ^= x4;       \
        x1 ^= x2;                                       \
        })

#define S1(x0, x1, x2, x3, x4) ({                       \
                                        x4  = x1;       \
        x1 ^= x0;       x0 ^= x3;       x3 = ~x3;       \
        x4 &= x1;       x0 |= x1;       x3 ^= x2;       \
        x0 ^= x3;       x1 ^= x3;       x3 ^= x4;       \
        x1 |= x4;       x4 ^= x2;       x2 &= x0;       \
        x2 ^= x1;       x1 |= x0;       x0 = ~x0;       \
        x0 ^= x2;       x4 ^= x1;                       \
        })

#define S2(x0, x1, x2, x3, x4) ({                       \
                                        x3 = ~x3;       \
        x1 ^= x0;       x4  = x0;       x0 &= x2;       \
        x0 ^= x3;       x3 |= x4;       x2 ^= x1;       \
        x3 ^= x1;       x1 &= x0;       x0 ^= x2;       \
        x2 &= x3;       x3 |= x1;       x0 = ~x0;       \
        x3 ^= x0;       x4 ^= x0;       x0 ^= x2;       \
        x1 |= x2;                                       \
        })

#define S3(x0, x1, x2, x3, x4) ({                       \
                                        x4  = x1;       \
        x1 ^= x3;       x3 |= x0;       x4 &= x0;       \
        x0 ^= x2;       x2 ^= x1;       x1 &= x3;       \
        x2 ^= x3;       x0 |= x4;       x4 ^= x3;       \
        x1 ^= x0;       x0 &= x3;       x3 &= x4;       \
        x3 ^= x2;       x4 |= x1;       x2 &= x1;       \
        x4 ^= x3;       x0 ^= x3;       x3 ^= x2;       \
        })

#define S4(x0, x1, x2, x3, x4) ({                       \
                                        x4  = x3;       \
        x3 &= x0;       x0 ^= x4;                       \
        x3 ^= x2;       x2 |= x4;       x0 ^= x1;       \
        x4 ^= x3;       x2 |= x0;                       \
        x2 ^= x1;       x1 &= x0;                       \
        x1 ^= x4;       x4 &= x2;       x2 ^= x3;       \
        x4 ^= x0;       x3 |= x1;       x1 = ~x1;       \
        x3 ^= x0;                                       \
        })

#define S5(x0, x1, x2, x3, x4) ({                       \
        x4  = x1;       x1 |= x0;                       \
        x2 ^= x1;       x3 = ~x3;       x4 ^= x0;       \
        x0 ^= x2;       x1 &= x4;       x4 |= x3;       \
        x4 ^= x0;       x0 &= x3;       x1 ^= x3;       \
        x3 ^= x2;       x0 ^= x1;       x2 &= x4;       \
        x1 ^= x2;       x2 &= x0;                       \
        x3 ^= x2;                                       \
        })

#define S6(x0, x1, x2, x3, x4) ({                       \
                                        x4  = x1;       \
        x3 ^= x0;       x1 ^= x2;       x2 ^= x0;       \
        x0 &= x3;       x1 |= x3;       x4 = ~x4;       \
        x0 ^= x1;       x1 ^= x2;                       \
        x3 ^= x4;       x4 ^= x0;       x2 &= x0;       \
        x4 ^= x1;       x2 ^= x3;       x3 &= x1;       \
        x3 ^= x0;       x1 ^= x2;                       \
        })

#define S7(x0, x1, x2, x3, x4) ({                       \
                                        x1 = ~x1;       \
        x4  = x1;       x0 = ~x0;       x1 &= x2;       \
        x1 ^= x3;       x3 |= x4;       x4 ^= x2;       \
        x2 ^= x3;       x3 ^= x0;       x0 |= x1;       \
        x2 &= x0;       x0 ^= x4;       x4 ^= x3;       \
        x3 &= x0;       x4 ^= x1;                       \
        x2 ^= x4;       x3 ^= x1;       x4 |= x0;       \
        x4 ^= x1;                                       \
        })

#define SI0(x0, x1, x2, x3, x4) ({                      \
                        x4  = x3;       x1 ^= x0;       \
        x3 |= x1;       x4 ^= x1;       x0 = ~x0;       \
        x2 ^= x3;       x3 ^= x0;       x0 &= x1;       \
        x0 ^= x2;       x2 &= x3;       x3 ^= x4;       \
        x2 ^= x3;       x1 ^= x3;       x3 &= x0;       \
        x1 ^= x0;       x0 ^= x2;       x4 ^= x3;       \
        })

#define SI1(x0, x1, x2, x3, x4) ({                      \
        x1 ^= x3;       x4  = x0;                       \
        x0 ^= x2;       x2 = ~x2;       x4 |= x1;       \
        x4 ^= x3;       x3 &= x1;       x1 ^= x2;       \
        x2 &= x4;       x4 ^= x1;       x1 |= x3;       \
        x3 ^= x0;       x2 ^= x0;       x0 |= x4;       \
        x2 ^= x4;       x1 ^= x0;                       \
        x4 ^= x1;                                       \
        })

#define SI2(x0, x1, x2, x3, x4) ({                      \
        x2 ^= x1;       x4  = x3;       x3 = ~x3;       \
        x3 |= x2;       x2 ^= x4;       x4 ^= x0;       \
        x3 ^= x1;       x1 |= x2;       x2 ^= x0;       \
        x1 ^= x4;       x4 |= x3;       x2 ^= x3;       \
        x4 ^= x2;       x2 &= x1;                       \
        x2 ^= x3;       x3 ^= x4;       x4 ^= x0;       \
        })

#define SI3(x0, x1, x2, x3, x4) ({                      \
                                        x2 ^= x1;       \
        x4  = x1;       x1 &= x2;                       \
        x1 ^= x0;       x0 |= x4;       x4 ^= x3;       \
        x0 ^= x3;       x3 |= x1;       x1 ^= x2;       \
        x1 ^= x3;       x0 ^= x2;       x2 ^= x3;       \
        x3 &= x1;       x1 ^= x0;       x0 &= x2;       \
        x4 ^= x3;       x3 ^= x0;       x0 ^= x1;       \
        })

#define SI4(x0, x1, x2, x3, x4) ({                      \
        x2 ^= x3;       x4  = x0;       x0 &= x1;       \
        x0 ^= x2;       x2 |= x3;       x4 = ~x4;       \
        x1 ^= x0;       x0 ^= x2;       x2 &= x4;       \
        x2 ^= x0;       x0 |= x4;                       \
        x0 ^= x3;       x3 &= x2;                       \
        x4 ^= x3;       x3 ^= x1;       x1 &= x0;       \
        x4 ^= x1;       x0 ^= x3;                       \
        })

#define SI5(x0, x1, x2, x3, x4) ({                      \
                        x4  = x1;       x1 |= x2;       \
        x2 ^= x4;       x1 ^= x3;       x3 &= x4;       \
        x2 ^= x3;       x3 |= x0;       x0 = ~x0;       \
        x3 ^= x2;       x2 |= x0;       x4 ^= x1;       \
        x2 ^= x4;       x4 &= x0;       x0 ^= x1;       \
        x1 ^= x3;       x0 &= x2;       x2 ^= x3;       \
        x0 ^= x2;       x2 ^= x4;       x4 ^= x3;       \
        })

#define SI6(x0, x1, x2, x3, x4) ({                      \
                        x0 ^= x2;                       \
        x4  = x0;       x0 &= x3;       x2 ^= x3;       \
        x0 ^= x2;       x3 ^= x1;       x2 |= x4;       \
        x2 ^= x3;       x3 &= x0;       x0 = ~x0;       \
        x3 ^= x1;       x1 &= x2;       x4 ^= x0;       \
        x3 ^= x4;       x4 ^= x2;       x0 ^= x1;       \
        x2 ^= x0;                                       \
        })

#define SI7(x0, x1, x2, x3, x4) ({                      \
        x4  = x3;       x3 &= x0;       x0 ^= x2;       \
        x2 |= x4;       x4 ^= x1;       x0 = ~x0;       \
        x1 |= x3;       x4 ^= x0;       x0 &= x2;       \
        x0 ^= x1;       x1 &= x2;       x3 ^= x2;       \
        x4 ^= x3;       x2 &= x3;       x3 |= x0;       \
        x1 ^= x4;       x3 ^= x4;       x4 &= x0;       \
        x4 ^= x2;                                       \
        })

/*
 * both gcc and clang have misoptimized this function in the past,
 * producing horrible object code from spilling temporary variables
 * on the stack. Forcing this part out of line avoids that.
 */
static noinline void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2,
                                           u32 r3, u32 r4, u32 *k)
{
        k += 100;
        S3(r3, r4, r0, r1, r2); store_and_load_keys(r1, r2, r4, r3, 28, 24);
        S4(r1, r2, r4, r3, r0); store_and_load_keys(r2, r4, r3, r0, 24, 20);
        S5(r2, r4, r3, r0, r1); store_and_load_keys(r1, r2, r4, r0, 20, 16);
        S6(r1, r2, r4, r0, r3); store_and_load_keys(r4, r3, r2, r0, 16, 12);
        S7(r4, r3, r2, r0, r1); store_and_load_keys(r1, r2, r0, r4, 12, 8);
        S0(r1, r2, r0, r4, r3); store_and_load_keys(r0, r2, r4, r1, 8, 4);
        S1(r0, r2, r4, r1, r3); store_and_load_keys(r3, r4, r1, r0, 4, 0);
        S2(r3, r4, r1, r0, r2); store_and_load_keys(r2, r4, r3, r0, 0, -4);
        S3(r2, r4, r3, r0, r1); store_and_load_keys(r0, r1, r4, r2, -4, -8);
        S4(r0, r1, r4, r2, r3); store_and_load_keys(r1, r4, r2, r3, -8, -12);
        S5(r1, r4, r2, r3, r0); store_and_load_keys(r0, r1, r4, r3, -12, -16);
        S6(r0, r1, r4, r3, r2); store_and_load_keys(r4, r2, r1, r3, -16, -20);
        S7(r4, r2, r1, r3, r0); store_and_load_keys(r0, r1, r3, r4, -20, -24);
        S0(r0, r1, r3, r4, r2); store_and_load_keys(r3, r1, r4, r0, -24, -28);
        k -= 50;
        S1(r3, r1, r4, r0, r2); store_and_load_keys(r2, r4, r0, r3, 22, 18);
        S2(r2, r4, r0, r3, r1); store_and_load_keys(r1, r4, r2, r3, 18, 14);
        S3(r1, r4, r2, r3, r0); store_and_load_keys(r3, r0, r4, r1, 14, 10);
        S4(r3, r0, r4, r1, r2); store_and_load_keys(r0, r4, r1, r2, 10, 6);
        S5(r0, r4, r1, r2, r3); store_and_load_keys(r3, r0, r4, r2, 6, 2);
        S6(r3, r0, r4, r2, r1); store_and_load_keys(r4, r1, r0, r2, 2, -2);
        S7(r4, r1, r0, r2, r3); store_and_load_keys(r3, r0, r2, r4, -2, -6);
        S0(r3, r0, r2, r4, r1); store_and_load_keys(r2, r0, r4, r3, -6, -10);
        S1(r2, r0, r4, r3, r1); store_and_load_keys(r1, r4, r3, r2, -10, -14);
        S2(r1, r4, r3, r2, r0); store_and_load_keys(r0, r4, r1, r2, -14, -18);
        S3(r0, r4, r1, r2, r3); store_and_load_keys(r2, r3, r4, r0, -18, -22);
        k -= 50;
        S4(r2, r3, r4, r0, r1); store_and_load_keys(r3, r4, r0, r1, 28, 24);
        S5(r3, r4, r0, r1, r2); store_and_load_keys(r2, r3, r4, r1, 24, 20);
        S6(r2, r3, r4, r1, r0); store_and_load_keys(r4, r0, r3, r1, 20, 16);
        S7(r4, r0, r3, r1, r2); store_and_load_keys(r2, r3, r1, r4, 16, 12);
        S0(r2, r3, r1, r4, r0); store_and_load_keys(r1, r3, r4, r2, 12, 8);
        S1(r1, r3, r4, r2, r0); store_and_load_keys(r0, r4, r2, r1, 8, 4);
        S2(r0, r4, r2, r1, r3); store_and_load_keys(r3, r4, r0, r1, 4, 0);
        S3(r3, r4, r0, r1, r2); storekeys(r1, r2, r4, r3, 0);
}

int __serpent_setkey(struct serpent_ctx *ctx, const u8 *key,
                     unsigned int keylen)
{
        u32 *k = ctx->expkey;
        u8  *k8 = (u8 *)k;
        u32 r0, r1, r2, r3, r4;
        __le32 *lk;
        int i;

        /* Copy key, add padding */

        for (i = 0; i < keylen; ++i)
                k8[i] = key[i];
        if (i < SERPENT_MAX_KEY_SIZE)
                k8[i++] = 1;
        while (i < SERPENT_MAX_KEY_SIZE)
                k8[i++] = 0;

        lk = (__le32 *)k;
        k[0] = le32_to_cpu(lk[0]);
        k[1] = le32_to_cpu(lk[1]);
        k[2] = le32_to_cpu(lk[2]);
        k[3] = le32_to_cpu(lk[3]);
        k[4] = le32_to_cpu(lk[4]);
        k[5] = le32_to_cpu(lk[5]);
        k[6] = le32_to_cpu(lk[6]);
        k[7] = le32_to_cpu(lk[7]);

        /* Expand key using polynomial */

        r0 = k[3];
        r1 = k[4];
        r2 = k[5];
        r3 = k[6];
        r4 = k[7];

        keyiter(k[0], r0, r4, r2, 0, 0);
        keyiter(k[1], r1, r0, r3, 1, 1);
        keyiter(k[2], r2, r1, r4, 2, 2);
        keyiter(k[3], r3, r2, r0, 3, 3);
        keyiter(k[4], r4, r3, r1, 4, 4);
        keyiter(k[5], r0, r4, r2, 5, 5);
        keyiter(k[6], r1, r0, r3, 6, 6);
        keyiter(k[7], r2, r1, r4, 7, 7);

        keyiter(k[0], r3, r2, r0, 8, 8);
        keyiter(k[1], r4, r3, r1, 9, 9);
        keyiter(k[2], r0, r4, r2, 10, 10);
        keyiter(k[3], r1, r0, r3, 11, 11);
        keyiter(k[4], r2, r1, r4, 12, 12);
        keyiter(k[5], r3, r2, r0, 13, 13);
        keyiter(k[6], r4, r3, r1, 14, 14);
        keyiter(k[7], r0, r4, r2, 15, 15);
        keyiter(k[8], r1, r0, r3, 16, 16);
        keyiter(k[9], r2, r1, r4, 17, 17);
        keyiter(k[10], r3, r2, r0, 18, 18);
        keyiter(k[11], r4, r3, r1, 19, 19);
        keyiter(k[12], r0, r4, r2, 20, 20);
        keyiter(k[13], r1, r0, r3, 21, 21);
        keyiter(k[14], r2, r1, r4, 22, 22);
        keyiter(k[15], r3, r2, r0, 23, 23);
        keyiter(k[16], r4, r3, r1, 24, 24);
        keyiter(k[17], r0, r4, r2, 25, 25);
        keyiter(k[18], r1, r0, r3, 26, 26);
        keyiter(k[19], r2, r1, r4, 27, 27);
        keyiter(k[20], r3, r2, r0, 28, 28);
        keyiter(k[21], r4, r3, r1, 29, 29);
        keyiter(k[22], r0, r4, r2, 30, 30);
        keyiter(k[23], r1, r0, r3, 31, 31);

        k += 50;

        keyiter(k[-26], r2, r1, r4, 32, -18);
        keyiter(k[-25], r3, r2, r0, 33, -17);
        keyiter(k[-24], r4, r3, r1, 34, -16);
        keyiter(k[-23], r0, r4, r2, 35, -15);
        keyiter(k[-22], r1, r0, r3, 36, -14);
        keyiter(k[-21], r2, r1, r4, 37, -13);
        keyiter(k[-20], r3, r2, r0, 38, -12);
        keyiter(k[-19], r4, r3, r1, 39, -11);
        keyiter(k[-18], r0, r4, r2, 40, -10);
        keyiter(k[-17], r1, r0, r3, 41, -9);
        keyiter(k[-16], r2, r1, r4, 42, -8);
        keyiter(k[-15], r3, r2, r0, 43, -7);
        keyiter(k[-14], r4, r3, r1, 44, -6);
        keyiter(k[-13], r0, r4, r2, 45, -5);
        keyiter(k[-12], r1, r0, r3, 46, -4);
        keyiter(k[-11], r2, r1, r4, 47, -3);
        keyiter(k[-10], r3, r2, r0, 48, -2);
        keyiter(k[-9], r4, r3, r1, 49, -1);
        keyiter(k[-8], r0, r4, r2, 50, 0);
        keyiter(k[-7], r1, r0, r3, 51, 1);
        keyiter(k[-6], r2, r1, r4, 52, 2);
        keyiter(k[-5], r3, r2, r0, 53, 3);
        keyiter(k[-4], r4, r3, r1, 54, 4);
        keyiter(k[-3], r0, r4, r2, 55, 5);
        keyiter(k[-2], r1, r0, r3, 56, 6);
        keyiter(k[-1], r2, r1, r4, 57, 7);
        keyiter(k[0], r3, r2, r0, 58, 8);
        keyiter(k[1], r4, r3, r1, 59, 9);
        keyiter(k[2], r0, r4, r2, 60, 10);
        keyiter(k[3], r1, r0, r3, 61, 11);
        keyiter(k[4], r2, r1, r4, 62, 12);
        keyiter(k[5], r3, r2, r0, 63, 13);
        keyiter(k[6], r4, r3, r1, 64, 14);
        keyiter(k[7], r0, r4, r2, 65, 15);
        keyiter(k[8], r1, r0, r3, 66, 16);
        keyiter(k[9], r2, r1, r4, 67, 17);
        keyiter(k[10], r3, r2, r0, 68, 18);
        keyiter(k[11], r4, r3, r1, 69, 19);
        keyiter(k[12], r0, r4, r2, 70, 20);
        keyiter(k[13], r1, r0, r3, 71, 21);
        keyiter(k[14], r2, r1, r4, 72, 22);
        keyiter(k[15], r3, r2, r0, 73, 23);
        keyiter(k[16], r4, r3, r1, 74, 24);
        keyiter(k[17], r0, r4, r2, 75, 25);
        keyiter(k[18], r1, r0, r3, 76, 26);
        keyiter(k[19], r2, r1, r4, 77, 27);
        keyiter(k[20], r3, r2, r0, 78, 28);
        keyiter(k[21], r4, r3, r1, 79, 29);
        keyiter(k[22], r0, r4, r2, 80, 30);
        keyiter(k[23], r1, r0, r3, 81, 31);

        k += 50;

        keyiter(k[-26], r2, r1, r4, 82, -18);
        keyiter(k[-25], r3, r2, r0, 83, -17);
        keyiter(k[-24], r4, r3, r1, 84, -16);
        keyiter(k[-23], r0, r4, r2, 85, -15);
        keyiter(k[-22], r1, r0, r3, 86, -14);
        keyiter(k[-21], r2, r1, r4, 87, -13);
        keyiter(k[-20], r3, r2, r0, 88, -12);
        keyiter(k[-19], r4, r3, r1, 89, -11);
        keyiter(k[-18], r0, r4, r2, 90, -10);
        keyiter(k[-17], r1, r0, r3, 91, -9);
        keyiter(k[-16], r2, r1, r4, 92, -8);
        keyiter(k[-15], r3, r2, r0, 93, -7);
        keyiter(k[-14], r4, r3, r1, 94, -6);
        keyiter(k[-13], r0, r4, r2, 95, -5);
        keyiter(k[-12], r1, r0, r3, 96, -4);
        keyiter(k[-11], r2, r1, r4, 97, -3);
        keyiter(k[-10], r3, r2, r0, 98, -2);
        keyiter(k[-9], r4, r3, r1, 99, -1);
        keyiter(k[-8], r0, r4, r2, 100, 0);
        keyiter(k[-7], r1, r0, r3, 101, 1);
        keyiter(k[-6], r2, r1, r4, 102, 2);
        keyiter(k[-5], r3, r2, r0, 103, 3);
        keyiter(k[-4], r4, r3, r1, 104, 4);
        keyiter(k[-3], r0, r4, r2, 105, 5);
        keyiter(k[-2], r1, r0, r3, 106, 6);
        keyiter(k[-1], r2, r1, r4, 107, 7);
        keyiter(k[0], r3, r2, r0, 108, 8);
        keyiter(k[1], r4, r3, r1, 109, 9);
        keyiter(k[2], r0, r4, r2, 110, 10);
        keyiter(k[3], r1, r0, r3, 111, 11);
        keyiter(k[4], r2, r1, r4, 112, 12);
        keyiter(k[5], r3, r2, r0, 113, 13);
        keyiter(k[6], r4, r3, r1, 114, 14);
        keyiter(k[7], r0, r4, r2, 115, 15);
        keyiter(k[8], r1, r0, r3, 116, 16);
        keyiter(k[9], r2, r1, r4, 117, 17);
        keyiter(k[10], r3, r2, r0, 118, 18);
        keyiter(k[11], r4, r3, r1, 119, 19);
        keyiter(k[12], r0, r4, r2, 120, 20);
        keyiter(k[13], r1, r0, r3, 121, 21);
        keyiter(k[14], r2, r1, r4, 122, 22);
        keyiter(k[15], r3, r2, r0, 123, 23);
        keyiter(k[16], r4, r3, r1, 124, 24);
        keyiter(k[17], r0, r4, r2, 125, 25);
        keyiter(k[18], r1, r0, r3, 126, 26);
        keyiter(k[19], r2, r1, r4, 127, 27);
        keyiter(k[20], r3, r2, r0, 128, 28);
        keyiter(k[21], r4, r3, r1, 129, 29);
        keyiter(k[22], r0, r4, r2, 130, 30);
        keyiter(k[23], r1, r0, r3, 131, 31);

        /* Apply S-boxes */
        __serpent_setkey_sbox(r0, r1, r2, r3, r4, ctx->expkey);

        return 0;
}
EXPORT_SYMBOL_GPL(__serpent_setkey);

int serpent_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
        return __serpent_setkey(crypto_tfm_ctx(tfm), key, keylen);
}
EXPORT_SYMBOL_GPL(serpent_setkey);

void __serpent_encrypt(const void *c, u8 *dst, const u8 *src)
{
        const struct serpent_ctx *ctx = c;
        const u32 *k = ctx->expkey;
        u32     r0, r1, r2, r3, r4;

        r0 = get_unaligned_le32(src);
        r1 = get_unaligned_le32(src + 4);
        r2 = get_unaligned_le32(src + 8);
        r3 = get_unaligned_le32(src + 12);

                                        K(r0, r1, r2, r3, 0);
        S0(r0, r1, r2, r3, r4);         LK(r2, r1, r3, r0, r4, 1);
        S1(r2, r1, r3, r0, r4);         LK(r4, r3, r0, r2, r1, 2);
        S2(r4, r3, r0, r2, r1);         LK(r1, r3, r4, r2, r0, 3);
        S3(r1, r3, r4, r2, r0);         LK(r2, r0, r3, r1, r4, 4);
        S4(r2, r0, r3, r1, r4);         LK(r0, r3, r1, r4, r2, 5);
        S5(r0, r3, r1, r4, r2);         LK(r2, r0, r3, r4, r1, 6);
        S6(r2, r0, r3, r4, r1);         LK(r3, r1, r0, r4, r2, 7);
        S7(r3, r1, r0, r4, r2);         LK(r2, r0, r4, r3, r1, 8);
        S0(r2, r0, r4, r3, r1);         LK(r4, r0, r3, r2, r1, 9);
        S1(r4, r0, r3, r2, r1);         LK(r1, r3, r2, r4, r0, 10);
        S2(r1, r3, r2, r4, r0);         LK(r0, r3, r1, r4, r2, 11);
        S3(r0, r3, r1, r4, r2);         LK(r4, r2, r3, r0, r1, 12);
        S4(r4, r2, r3, r0, r1);         LK(r2, r3, r0, r1, r4, 13);
        S5(r2, r3, r0, r1, r4);         LK(r4, r2, r3, r1, r0, 14);
        S6(r4, r2, r3, r1, r0);         LK(r3, r0, r2, r1, r4, 15);
        S7(r3, r0, r2, r1, r4);         LK(r4, r2, r1, r3, r0, 16);
        S0(r4, r2, r1, r3, r0);         LK(r1, r2, r3, r4, r0, 17);
        S1(r1, r2, r3, r4, r0);         LK(r0, r3, r4, r1, r2, 18);
        S2(r0, r3, r4, r1, r2);         LK(r2, r3, r0, r1, r4, 19);
        S3(r2, r3, r0, r1, r4);         LK(r1, r4, r3, r2, r0, 20);
        S4(r1, r4, r3, r2, r0);         LK(r4, r3, r2, r0, r1, 21);
        S5(r4, r3, r2, r0, r1);         LK(r1, r4, r3, r0, r2, 22);
        S6(r1, r4, r3, r0, r2);         LK(r3, r2, r4, r0, r1, 23);
        S7(r3, r2, r4, r0, r1);         LK(r1, r4, r0, r3, r2, 24);
        S0(r1, r4, r0, r3, r2);         LK(r0, r4, r3, r1, r2, 25);
        S1(r0, r4, r3, r1, r2);         LK(r2, r3, r1, r0, r4, 26);
        S2(r2, r3, r1, r0, r4);         LK(r4, r3, r2, r0, r1, 27);
        S3(r4, r3, r2, r0, r1);         LK(r0, r1, r3, r4, r2, 28);
        S4(r0, r1, r3, r4, r2);         LK(r1, r3, r4, r2, r0, 29);
        S5(r1, r3, r4, r2, r0);         LK(r0, r1, r3, r2, r4, 30);
        S6(r0, r1, r3, r2, r4);         LK(r3, r4, r1, r2, r0, 31);
        S7(r3, r4, r1, r2, r0);         K(r0, r1, r2, r3, 32);

        put_unaligned_le32(r0, dst);
        put_unaligned_le32(r1, dst + 4);
        put_unaligned_le32(r2, dst + 8);
        put_unaligned_le32(r3, dst + 12);
}
EXPORT_SYMBOL_GPL(__serpent_encrypt);

static void serpent_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
        struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);

        __serpent_encrypt(ctx, dst, src);
}

void __serpent_decrypt(const void *c, u8 *dst, const u8 *src)
{
        const struct serpent_ctx *ctx = c;
        const u32 *k = ctx->expkey;
        u32     r0, r1, r2, r3, r4;

        r0 = get_unaligned_le32(src);
        r1 = get_unaligned_le32(src + 4);
        r2 = get_unaligned_le32(src + 8);
        r3 = get_unaligned_le32(src + 12);

                                        K(r0, r1, r2, r3, 32);
        SI7(r0, r1, r2, r3, r4);        KL(r1, r3, r0, r4, r2, 31);
        SI6(r1, r3, r0, r4, r2);        KL(r0, r2, r4, r1, r3, 30);
        SI5(r0, r2, r4, r1, r3);        KL(r2, r3, r0, r4, r1, 29);
        SI4(r2, r3, r0, r4, r1);        KL(r2, r0, r1, r4, r3, 28);
        SI3(r2, r0, r1, r4, r3);        KL(r1, r2, r3, r4, r0, 27);
        SI2(r1, r2, r3, r4, r0);        KL(r2, r0, r4, r3, r1, 26);
        SI1(r2, r0, r4, r3, r1);        KL(r1, r0, r4, r3, r2, 25);
        SI0(r1, r0, r4, r3, r2);        KL(r4, r2, r0, r1, r3, 24);
        SI7(r4, r2, r0, r1, r3);        KL(r2, r1, r4, r3, r0, 23);
        SI6(r2, r1, r4, r3, r0);        KL(r4, r0, r3, r2, r1, 22);
        SI5(r4, r0, r3, r2, r1);        KL(r0, r1, r4, r3, r2, 21);
        SI4(r0, r1, r4, r3, r2);        KL(r0, r4, r2, r3, r1, 20);
        SI3(r0, r4, r2, r3, r1);        KL(r2, r0, r1, r3, r4, 19);
        SI2(r2, r0, r1, r3, r4);        KL(r0, r4, r3, r1, r2, 18);
        SI1(r0, r4, r3, r1, r2);        KL(r2, r4, r3, r1, r0, 17);
        SI0(r2, r4, r3, r1, r0);        KL(r3, r0, r4, r2, r1, 16);
        SI7(r3, r0, r4, r2, r1);        KL(r0, r2, r3, r1, r4, 15);
        SI6(r0, r2, r3, r1, r4);        KL(r3, r4, r1, r0, r2, 14);
        SI5(r3, r4, r1, r0, r2);        KL(r4, r2, r3, r1, r0, 13);
        SI4(r4, r2, r3, r1, r0);        KL(r4, r3, r0, r1, r2, 12);
        SI3(r4, r3, r0, r1, r2);        KL(r0, r4, r2, r1, r3, 11);
        SI2(r0, r4, r2, r1, r3);        KL(r4, r3, r1, r2, r0, 10);
        SI1(r4, r3, r1, r2, r0);        KL(r0, r3, r1, r2, r4, 9);
        SI0(r0, r3, r1, r2, r4);        KL(r1, r4, r3, r0, r2, 8);
        SI7(r1, r4, r3, r0, r2);        KL(r4, r0, r1, r2, r3, 7);
        SI6(r4, r0, r1, r2, r3);        KL(r1, r3, r2, r4, r0, 6);
        SI5(r1, r3, r2, r4, r0);        KL(r3, r0, r1, r2, r4, 5);
        SI4(r3, r0, r1, r2, r4);        KL(r3, r1, r4, r2, r0, 4);
        SI3(r3, r1, r4, r2, r0);        KL(r4, r3, r0, r2, r1, 3);
        SI2(r4, r3, r0, r2, r1);        KL(r3, r1, r2, r0, r4, 2);
        SI1(r3, r1, r2, r0, r4);        KL(r4, r1, r2, r0, r3, 1);
        SI0(r4, r1, r2, r0, r3);        K(r2, r3, r1, r4, 0);

        put_unaligned_le32(r2, dst);
        put_unaligned_le32(r3, dst + 4);
        put_unaligned_le32(r1, dst + 8);
        put_unaligned_le32(r4, dst + 12);
}
EXPORT_SYMBOL_GPL(__serpent_decrypt);

static void serpent_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
        struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);

        __serpent_decrypt(ctx, dst, src);
}

static struct crypto_alg srp_alg = {
        .cra_name               =       "serpent",
        .cra_driver_name        =       "serpent-generic",
        .cra_priority           =       100,
        .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
        .cra_blocksize          =       SERPENT_BLOCK_SIZE,
        .cra_ctxsize            =       sizeof(struct serpent_ctx),
        .cra_module             =       THIS_MODULE,
        .cra_u                  =       { .cipher = {
        .cia_min_keysize        =       SERPENT_MIN_KEY_SIZE,
        .cia_max_keysize        =       SERPENT_MAX_KEY_SIZE,
        .cia_setkey             =       serpent_setkey,
        .cia_encrypt            =       serpent_encrypt,
        .cia_decrypt            =       serpent_decrypt } }
};

static int __init serpent_mod_init(void)
{
        return crypto_register_alg(&srp_alg);
}

static void __exit serpent_mod_fini(void)
{
        crypto_unregister_alg(&srp_alg);
}

module_init(serpent_mod_init);
module_exit(serpent_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Serpent Cipher Algorithm");
MODULE_AUTHOR("Dag Arne Osvik <osvik@ii.uib.no>");
MODULE_ALIAS_CRYPTO("serpent");
MODULE_ALIAS_CRYPTO("serpent-generic");