Problem - Kevin Tafuro

c->ix = 0;
c->tl = 0;
}
static void spc_mdc2_oneblock(SPC_MDC2_CTX *c, unsigned char bl[SPC_BLOCK_SZ]) {
int i, j;
SPC_KEY_SCHED ks1, ks2;
SPC_ENCRYPT_INIT(&ks1, c->h1, SPC_BLOCK_SZ);
SPC_ENCRYPT_INIT(&ks2, c->h2, SPC_BLOCK_SZ);
SPC_DO_ENCRYPT(&ks1, bl, c->h1);
SPC_DO_ENCRYPT(&ks2, bl, c->h2);
j = SPC_BLOCK_SZ / (sizeof(int) * 2);
for (i = 0; i < SPC_BLOCK_SZ / (sizeof(int) * 2); i++) {
((int *)c->h1)[i] ^= ((int *)bl)[i];
((int *)c->h2)[i] ^= ((int *)bl)[i];
((int *)c->h1)[i + j] ^= ((int *)bl)[i + j];
((int *)c->h2)[i + j] ^= ((int *)bl)[i + j];
/* Now swap the lower halves using XOR. */
((int *)c->h1)[i + j] ^= ((int *)c->h2)[i + j];
((int *)c->h2)[i + j] ^= ((int *)c->h1)[i + j];
((int *)c->h1)[i + j] ^= ((int *)c->h2)[i + j];
}
}
void spc_mdc2_update(SPC_MDC2_CTX *c, unsigned char *t, size_t l) {
c->tl += l; /* if c->tl < l: abort */
while (c->ix && l) {
c->bf[c->ix++] = *t++;
l--;
if (!(c->ix %= SPC_BLOCK_SZ))
spc_mdc2_oneblock(c, c->bf);
}
while (l > SPC_BLOCK_SZ) {
spc_mdc2_oneblock(c, t);
t += SPC_BLOCK_SZ;
l -= SPC_BLOCK_SZ;
}
c->ix = l;
for (l = 0; l < c->ix; l++)
c->bf[l] = *t++;
}
void spc_mdc2_final(SPC_MDC2_CTX *c, unsigned char output[SPC_BLOCK_SZ * 2]) {
int i;
c->bf[c->ix++] = 0x80;
while (c->ix < SPC_BLOCK_SZ)
c->bf[c->ix++] = 0;
spc_mdc2_oneblock(c, c->bf);
memset(c->bf, 0, SPC_BLOCK_SZ - sizeof(size_t));
c->tl = htonl(c->tl);
for (i = 0; i < sizeof(size_t); i++)
c->bf[SPC_BLOCK_SZ - sizeof(size_t) + i] = ((unsigned char *)(&c->tl))[i];
Using a Block Cipher to Build a Full-Strength Hash Function | 297
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