summaryrefslogtreecommitdiff
path: root/src/ltc/ciphers/idea.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/ltc/ciphers/idea.c')
-rw-r--r--src/ltc/ciphers/idea.c90
1 files changed, 45 insertions, 45 deletions
diff --git a/src/ltc/ciphers/idea.c b/src/ltc/ciphers/idea.c
index 27db6167..b195a4c9 100644
--- a/src/ltc/ciphers/idea.c
+++ b/src/ltc/ciphers/idea.c
@@ -35,38 +35,38 @@ const struct ltc_cipher_descriptor idea_desc = {
typedef unsigned short int ushort16;
-#define _LOW16(x) ((x)&0xffff) /* compiler should be able to optimize this away if x is 16 bits */
-#define _HIGH16(x) ((x)>>16)
-#define _MUL(a,b) { \
- ulong32 p = (ulong32)_LOW16(a) * b; \
+#define LOW16(x) ((x)&0xffff) /* compiler should be able to optimize this away if x is 16 bits */
+#define HIGH16(x) ((x)>>16)
+#define MUL(a,b) { \
+ ulong32 p = (ulong32)LOW16(a) * b; \
if (p) { \
- p = _LOW16(p) - _HIGH16(p); \
- a = (ushort16)p - (ushort16)_HIGH16(p); \
+ p = LOW16(p) - HIGH16(p); \
+ a = (ushort16)p - (ushort16)HIGH16(p); \
} \
else \
a = 1 - a - b; \
}
-#define _STORE16(x,y) { (y)[0] = (unsigned char)(((x)>>8)&255); (y)[1] = (unsigned char)((x)&255); }
-#define _LOAD16(x,y) { x = ((ushort16)((y)[0] & 255)<<8) | ((ushort16)((y)[1] & 255)); }
+#define STORE16(x,y) { (y)[0] = (unsigned char)(((x)>>8)&255); (y)[1] = (unsigned char)((x)&255); }
+#define LOAD16(x,y) { x = ((ushort16)((y)[0] & 255)<<8) | ((ushort16)((y)[1] & 255)); }
-static ushort16 _mul_inv(ushort16 x)
+static ushort16 s_mul_inv(ushort16 x)
{
ushort16 y = x;
unsigned i;
for (i = 0; i < 15; i++) {
- _MUL(y, _LOW16(y));
- _MUL(y, x);
+ MUL(y, LOW16(y));
+ MUL(y, x);
}
- return _LOW16(y);
+ return LOW16(y);
}
-static ushort16 _add_inv(ushort16 x)
+static ushort16 s_add_inv(ushort16 x)
{
- return _LOW16(0 - x);
+ return LOW16(0 - x);
}
-static int _setup_key(const unsigned char *key, symmetric_key *skey)
+static int s_setup_key(const unsigned char *key, symmetric_key *skey)
{
int i, j;
ushort16 *e_key = skey->idea.ek;
@@ -74,49 +74,49 @@ static int _setup_key(const unsigned char *key, symmetric_key *skey)
/* prepare enc key */
for (i = 0; i < 8; i++) {
- _LOAD16(e_key[i], key + 2 * i);
+ LOAD16(e_key[i], key + 2 * i);
}
for (; i < LTC_IDEA_KEYLEN; i++) {
j = (i - i % 8) - 8;
- e_key[i] = _LOW16((e_key[j+(i+1)%8] << 9) | (e_key[j+(i+2)%8] >> 7));
+ e_key[i] = LOW16((e_key[j+(i+1)%8] << 9) | (e_key[j+(i+2)%8] >> 7));
}
/* prepare dec key */
for (i = 0; i < LTC_IDEA_ROUNDS; i++) {
- d_key[i*6+0] = _mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+0]);
- d_key[i*6+1] = _add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+1+(i>0 ? 1 : 0)]);
- d_key[i*6+2] = _add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+2-(i>0 ? 1 : 0)]);
- d_key[i*6+3] = _mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+3]);
- d_key[i*6+4] = e_key[(LTC_IDEA_ROUNDS-1-i)*6+4];
- d_key[i*6+5] = e_key[(LTC_IDEA_ROUNDS-1-i)*6+5];
+ d_key[i*6+0] = s_mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+0]);
+ d_key[i*6+1] = s_add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+1+(i>0 ? 1 : 0)]);
+ d_key[i*6+2] = s_add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+2-(i>0 ? 1 : 0)]);
+ d_key[i*6+3] = s_mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+3]);
+ d_key[i*6+4] = e_key[(LTC_IDEA_ROUNDS-1-i)*6+4];
+ d_key[i*6+5] = e_key[(LTC_IDEA_ROUNDS-1-i)*6+5];
}
- d_key[i*6+0] = _mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+0]);
- d_key[i*6+1] = _add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+1]);
- d_key[i*6+2] = _add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+2]);
- d_key[i*6+3] = _mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+3]);
+ d_key[i*6+0] = s_mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+0]);
+ d_key[i*6+1] = s_add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+1]);
+ d_key[i*6+2] = s_add_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+2]);
+ d_key[i*6+3] = s_mul_inv(e_key[(LTC_IDEA_ROUNDS-i)*6+3]);
return CRYPT_OK;
}
-static int _process_block(const unsigned char *in, unsigned char *out, const ushort16 *m_key)
+static int s_process_block(const unsigned char *in, unsigned char *out, const ushort16 *m_key)
{
int i;
ushort16 x0, x1, x2, x3, t0, t1;
- _LOAD16(x0, in + 0);
- _LOAD16(x1, in + 2);
- _LOAD16(x2, in + 4);
- _LOAD16(x3, in + 6);
+ LOAD16(x0, in + 0);
+ LOAD16(x1, in + 2);
+ LOAD16(x2, in + 4);
+ LOAD16(x3, in + 6);
for (i = 0; i < LTC_IDEA_ROUNDS; i++) {
- _MUL(x0, m_key[i*6+0]);
+ MUL(x0, m_key[i*6+0]);
x1 += m_key[i*6+1];
x2 += m_key[i*6+2];
- _MUL(x3, m_key[i*6+3]);
+ MUL(x3, m_key[i*6+3]);
t0 = x0^x2;
- _MUL(t0, m_key[i*6+4]);
+ MUL(t0, m_key[i*6+4]);
t1 = t0 + (x1^x3);
- _MUL(t1, m_key[i*6+5]);
+ MUL(t1, m_key[i*6+5]);
t0 += t1;
x0 ^= t1;
x3 ^= t0;
@@ -125,15 +125,15 @@ static int _process_block(const unsigned char *in, unsigned char *out, const ush
x2 = t0;
}
- _MUL(x0, m_key[LTC_IDEA_ROUNDS*6+0]);
+ MUL(x0, m_key[LTC_IDEA_ROUNDS*6+0]);
x2 += m_key[LTC_IDEA_ROUNDS*6+1];
x1 += m_key[LTC_IDEA_ROUNDS*6+2];
- _MUL(x3, m_key[LTC_IDEA_ROUNDS*6+3]);
+ MUL(x3, m_key[LTC_IDEA_ROUNDS*6+3]);
- _STORE16(x0, out + 0);
- _STORE16(x2, out + 2);
- _STORE16(x1, out + 4);
- _STORE16(x3, out + 6);
+ STORE16(x0, out + 0);
+ STORE16(x2, out + 2);
+ STORE16(x1, out + 4);
+ STORE16(x3, out + 6);
return CRYPT_OK;
}
@@ -146,12 +146,12 @@ int idea_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_k
if (num_rounds != 0 && num_rounds != 8) return CRYPT_INVALID_ROUNDS;
if (keylen != 16) return CRYPT_INVALID_KEYSIZE;
- return _setup_key(key, skey);
+ return s_setup_key(key, skey);
}
int idea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey)
{
- int err = _process_block(pt, ct, skey->idea.ek);
+ int err = s_process_block(pt, ct, skey->idea.ek);
#ifdef LTC_CLEAN_STACK
burn_stack(sizeof(ushort16) * 6 + sizeof(int));
#endif
@@ -160,7 +160,7 @@ int idea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric
int idea_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey)
{
- int err = _process_block(ct, pt, skey->idea.dk);
+ int err = s_process_block(ct, pt, skey->idea.dk);
#ifdef LTC_CLEAN_STACK
burn_stack(sizeof(ushort16) * 6 + sizeof(int));
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-03 16:25:24 +0000