void tmd_aes_generic_gcm_decrypt(uint8_t *output, const aes_gcm *gcm, const aes_ctx *ctx, const aes_key *key, const uint8_t *input, uint32_t length, aes_ctx *newCTX)
{
aes_block out;
memcpy(newCTX, ctx, sizeof(aes_ctx));
newCTX->length_input += length;
for (; length >= 16; input += 16, output += 16, length -= 16) {
block128_inc_be(&newCTX->civ);
aes_encrypt_block(&out, key, &newCTX->civ);
gcm_ghash_add(gcm, newCTX, (block128 *) input);
block128_xor(&out, (block128 *) input);
block128_copy((block128 *) output, &out);
}
if (length > 0) {
aes_block tmp;
int i;
block128_inc_be(&newCTX->civ);
block128_zero(&tmp);
block128_copy_bytes(&tmp, input, length);
gcm_ghash_add(gcm, newCTX, &tmp);
aes_encrypt_block(&out, key, &newCTX->civ);
block128_xor_bytes(&tmp, out.b, length);
for (i = 0; i < length; i++) {
output[i] = tmp.b[i];
}
}
}
void aes_gcm_decrypt(uint8_t *output, aes_gcm *gcm, uint8_t *input, uint32_t length)
{
aes_block out;
gcm->length_input += length;
for (; length >= 16; input += 16, output += 16, length -= 16) {
block128_inc_be(&gcm->civ);
aes_encrypt_block(&out, &gcm->key, &gcm->civ);
gcm_ghash_add(gcm, (block128 *) input);
block128_xor(&out, (block128 *) input);
block128_copy((block128 *) output, &out);
}
if (length > 0) {
aes_block tmp;
int i;
block128_inc_be(&gcm->civ);
block128_zero(&tmp);
block128_copy_bytes(&tmp, input, length);
gcm_ghash_add(gcm, &tmp);
aes_encrypt_block(&out, &gcm->key, &gcm->civ);
block128_xor_bytes(&tmp, out.b, length);
for (i = 0; i < length; i++) {
output[i] = tmp.b[i];
}
}
}
void tmd_aes_generic_encrypt_ctr(uint8_t *output, const aes_key *key, const aes_block *iv, aes_block *newIV, const uint8_t *input, uint32_t len)
{
aes_block block, o;
uint32_t nb_blocks = len / 16;
int i;
/* preload IV in block */
block128_copy(&block, iv);
for ( ; nb_blocks-- > 0; block128_inc_be(&block), output += 16, input += 16) {
aes_encrypt_block(&o, key, &block);
block128_vxor((block128 *) output, &o, (block128 *) input);
}
if ((len % 16) != 0) {
aes_encrypt_block(&o, key, &block);
for (i = 0; i < (len % 16); i++) {
*output = ((uint8_t *) &o)[i] ^ *input;
output++;
input++;
}
}
if(NULL != newIV)
block128_copy(newIV, &block);
}
void tmd_aes_gen_ctr(aes_block *output, const aes_key *key, aes_block *iv, uint32_t nb_blocks)
{
aes_block block;
/* preload IV in block */
block128_copy(&block, iv);
for ( ; nb_blocks-- > 0; output++, block128_inc_be(&block)) {
aes_encrypt_block(output, key, &block);
}
}
void aes_gen_ctr(uint8_t *output, aes_key *key, aes_block *iv, uint32_t nb_blocks)
{
aes_block block;
if (!nb_blocks)
return;
/* preload IV in block */
block128_copy(&block, iv);
for ( ; nb_blocks-- > 0; output += 16, block128_inc_be(&block)) {
aes_encrypt_block((block128 *) output, key, &block);
}
}
void aes_encrypt_ctr(uint8_t *output, aes_key *key, aes_block *iv, uint8_t *input, uint32_t len)
{
aes_block block, o;
uint32_t nb_blocks = len / 16;
int i;
/* preload IV in block */
block128_copy(&block, iv);
for ( ; nb_blocks-- > 0; block128_inc_be(&block), output += 16, input += 16) {
aes_encrypt_block(&o, key, &block);
block128_vxor((block128 *) output, &o, (block128 *) input);
}
if ((len % 16) != 0) {
aes_encrypt_block(&o, key, &block);
for (i = 0; i < (len % 16); i++) {
*output = ((uint8_t *) &o)[i] ^ *input;
output += 1;
input += 1;
}
}
}
