/* see bearssl_block.h */
void
br_aes_ct_cbcenc_run(const br_aes_ct_cbcenc_keys *ctx,
void *iv, void *data, size_t len)
{
unsigned char *buf, *ivbuf;
uint32_t q[8];
uint32_t iv0, iv1, iv2, iv3;
uint32_t sk_exp[120];
q[1] = 0;
q[3] = 0;
q[5] = 0;
q[7] = 0;
br_aes_ct_skey_expand(sk_exp, ctx->num_rounds, ctx->skey);
ivbuf = iv;
iv0 = br_dec32le(ivbuf);
iv1 = br_dec32le(ivbuf + 4);
iv2 = br_dec32le(ivbuf + 8);
iv3 = br_dec32le(ivbuf + 12);
buf = data;
while (len > 0) {
q[0] = iv0 ^ br_dec32le(buf);
q[2] = iv1 ^ br_dec32le(buf + 4);
q[4] = iv2 ^ br_dec32le(buf + 8);
q[6] = iv3 ^ br_dec32le(buf + 12);
br_aes_ct_ortho(q);
br_aes_ct_bitslice_encrypt(ctx->num_rounds, sk_exp, q);
br_aes_ct_ortho(q);
iv0 = q[0];
iv1 = q[2];
iv2 = q[4];
iv3 = q[6];
br_enc32le(buf, iv0);
br_enc32le(buf + 4, iv1);
br_enc32le(buf + 8, iv2);
br_enc32le(buf + 12, iv3);
buf += 16;
len -= 16;
}
br_enc32le(ivbuf, iv0);
br_enc32le(ivbuf + 4, iv1);
br_enc32le(ivbuf + 8, iv2);
br_enc32le(ivbuf + 12, iv3);
}
/* see bearssl_block.h */
void
br_aes_ct_cbcdec_run(const br_aes_ct_cbcdec_keys *ctx,
void *iv, void *data, size_t len)
{
unsigned char *buf, *ivbuf;
uint32_t iv0, iv1, iv2, iv3;
uint32_t sk_exp[120];
br_aes_ct_skey_expand(sk_exp, ctx->num_rounds, ctx->skey);
ivbuf = iv;
iv0 = br_dec32le(ivbuf);
iv1 = br_dec32le(ivbuf + 4);
iv2 = br_dec32le(ivbuf + 8);
iv3 = br_dec32le(ivbuf + 12);
buf = data;
while (len > 0) {
uint32_t q[8], sq[8];
q[0] = br_dec32le(buf);
q[2] = br_dec32le(buf + 4);
q[4] = br_dec32le(buf + 8);
q[6] = br_dec32le(buf + 12);
if (len >= 32) {
q[1] = br_dec32le(buf + 16);
q[3] = br_dec32le(buf + 20);
q[5] = br_dec32le(buf + 24);
q[7] = br_dec32le(buf + 28);
} else {
q[1] = 0;
q[3] = 0;
q[5] = 0;
q[7] = 0;
}
memcpy(sq, q, sizeof q);
br_aes_ct_ortho(q);
br_aes_ct_bitslice_decrypt(ctx->num_rounds, sk_exp, q);
br_aes_ct_ortho(q);
br_enc32le(buf, q[0] ^ iv0);
br_enc32le(buf + 4, q[2] ^ iv1);
br_enc32le(buf + 8, q[4] ^ iv2);
br_enc32le(buf + 12, q[6] ^ iv3);
if (len < 32) {
iv0 = sq[0];
iv1 = sq[2];
iv2 = sq[4];
iv3 = sq[6];
break;
}
br_enc32le(buf + 16, q[1] ^ sq[0]);
br_enc32le(buf + 20, q[3] ^ sq[2]);
br_enc32le(buf + 24, q[5] ^ sq[4]);
br_enc32le(buf + 28, q[7] ^ sq[6]);
iv0 = sq[1];
iv1 = sq[3];
iv2 = sq[5];
iv3 = sq[7];
buf += 32;
len -= 32;
}
br_enc32le(ivbuf, iv0);
br_enc32le(ivbuf + 4, iv1);
br_enc32le(ivbuf + 8, iv2);
br_enc32le(ivbuf + 12, iv3);
}