openssl/crypto/bf/bf_enc.c

176 lines
4.5 KiB
C

/*
* Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <openssl/blowfish.h>
#include "bf_local.h"
/*
* Blowfish as implemented from 'Blowfish: Springer-Verlag paper' (From
* LECTURE NOTES IN COMPUTER SCIENCE 809, FAST SOFTWARE ENCRYPTION, CAMBRIDGE
* SECURITY WORKSHOP, CAMBRIDGE, U.K., DECEMBER 9-11, 1993)
*/
#if (BF_ROUNDS != 16) && (BF_ROUNDS != 20)
# error If you set BF_ROUNDS to some value other than 16 or 20, you will have \
to modify the code.
#endif
void BF_encrypt(BF_LONG *data, const BF_KEY *key)
{
register BF_LONG l, r;
register const BF_LONG *p, *s;
p = key->P;
s = &(key->S[0]);
l = data[0];
r = data[1];
l ^= p[0];
BF_ENC(r, l, s, p[1]);
BF_ENC(l, r, s, p[2]);
BF_ENC(r, l, s, p[3]);
BF_ENC(l, r, s, p[4]);
BF_ENC(r, l, s, p[5]);
BF_ENC(l, r, s, p[6]);
BF_ENC(r, l, s, p[7]);
BF_ENC(l, r, s, p[8]);
BF_ENC(r, l, s, p[9]);
BF_ENC(l, r, s, p[10]);
BF_ENC(r, l, s, p[11]);
BF_ENC(l, r, s, p[12]);
BF_ENC(r, l, s, p[13]);
BF_ENC(l, r, s, p[14]);
BF_ENC(r, l, s, p[15]);
BF_ENC(l, r, s, p[16]);
# if BF_ROUNDS == 20
BF_ENC(r, l, s, p[17]);
BF_ENC(l, r, s, p[18]);
BF_ENC(r, l, s, p[19]);
BF_ENC(l, r, s, p[20]);
# endif
r ^= p[BF_ROUNDS + 1];
data[1] = l & 0xffffffffU;
data[0] = r & 0xffffffffU;
}
void BF_decrypt(BF_LONG *data, const BF_KEY *key)
{
register BF_LONG l, r;
register const BF_LONG *p, *s;
p = key->P;
s = &(key->S[0]);
l = data[0];
r = data[1];
l ^= p[BF_ROUNDS + 1];
# if BF_ROUNDS == 20
BF_ENC(r, l, s, p[20]);
BF_ENC(l, r, s, p[19]);
BF_ENC(r, l, s, p[18]);
BF_ENC(l, r, s, p[17]);
# endif
BF_ENC(r, l, s, p[16]);
BF_ENC(l, r, s, p[15]);
BF_ENC(r, l, s, p[14]);
BF_ENC(l, r, s, p[13]);
BF_ENC(r, l, s, p[12]);
BF_ENC(l, r, s, p[11]);
BF_ENC(r, l, s, p[10]);
BF_ENC(l, r, s, p[9]);
BF_ENC(r, l, s, p[8]);
BF_ENC(l, r, s, p[7]);
BF_ENC(r, l, s, p[6]);
BF_ENC(l, r, s, p[5]);
BF_ENC(r, l, s, p[4]);
BF_ENC(l, r, s, p[3]);
BF_ENC(r, l, s, p[2]);
BF_ENC(l, r, s, p[1]);
r ^= p[0];
data[1] = l & 0xffffffffU;
data[0] = r & 0xffffffffU;
}
void BF_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
const BF_KEY *schedule, unsigned char *ivec, int encrypt)
{
register BF_LONG tin0, tin1;
register BF_LONG tout0, tout1, xor0, xor1;
register long l = length;
BF_LONG tin[2];
if (encrypt) {
n2l(ivec, tout0);
n2l(ivec, tout1);
ivec -= 8;
for (l -= 8; l >= 0; l -= 8) {
n2l(in, tin0);
n2l(in, tin1);
tin0 ^= tout0;
tin1 ^= tout1;
tin[0] = tin0;
tin[1] = tin1;
BF_encrypt(tin, schedule);
tout0 = tin[0];
tout1 = tin[1];
l2n(tout0, out);
l2n(tout1, out);
}
if (l != -8) {
n2ln(in, tin0, tin1, l + 8);
tin0 ^= tout0;
tin1 ^= tout1;
tin[0] = tin0;
tin[1] = tin1;
BF_encrypt(tin, schedule);
tout0 = tin[0];
tout1 = tin[1];
l2n(tout0, out);
l2n(tout1, out);
}
l2n(tout0, ivec);
l2n(tout1, ivec);
} else {
n2l(ivec, xor0);
n2l(ivec, xor1);
ivec -= 8;
for (l -= 8; l >= 0; l -= 8) {
n2l(in, tin0);
n2l(in, tin1);
tin[0] = tin0;
tin[1] = tin1;
BF_decrypt(tin, schedule);
tout0 = tin[0] ^ xor0;
tout1 = tin[1] ^ xor1;
l2n(tout0, out);
l2n(tout1, out);
xor0 = tin0;
xor1 = tin1;
}
if (l != -8) {
n2l(in, tin0);
n2l(in, tin1);
tin[0] = tin0;
tin[1] = tin1;
BF_decrypt(tin, schedule);
tout0 = tin[0] ^ xor0;
tout1 = tin[1] ^ xor1;
l2nn(tout0, tout1, out, l + 8);
xor0 = tin0;
xor1 = tin1;
}
l2n(xor0, ivec);
l2n(xor1, ivec);
}
tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
tin[0] = tin[1] = 0;
}