AESENC128KL

Perform Ten Rounds of AES Encryption Flow With Key Locker Using 128-Bit Key

stableVMJITAOTinstruction

Encodings

Operand encoding

Each mode is a value of the Op/En column above. It says which field of the encoded instruction carries each operand, in the order they are written, and whether the instruction reads it, writes it or both.

Measured cost

Flags named

• CF Carry
• PF Parity
• AF Auxiliary carry
• ZF Zero
• SF Sign
• OF Overflow

Description#

The AESENC128KL1 instruction performs ten rounds of AES to encrypt the first operand using the 128-bit key indi-

cated by the handle from the second operand. It stores the result in the first operand if the operation succeeds

(e.g., does not run into a handle violation failure).

Operation#

AESENC128KL
Handle := UnalignedLoad of 384 bit (SRC); // Load is not guaranteed to be atomic.
Illegal Handle = (

                   HandleReservedBitSet (Handle) ||
                   (Handle[0] AND (CPL > 0)) ||
                   Handle [1] ||
                   HandleKeyType (Handle) != HANDLE_KEY_TYPE_AES128
                   );
IF (Illegal Handle) {
    THEN RFLAGS.ZF := 1;
    ELSE
          (UnwrappedKey, Authentic) := UnwrapKeyAndAuthenticate384 (Handle[383:0], IWKey);
          IF (Authentic == 0)
          THEN RFLAGS.ZF := 1;
          ELSE
                DEST := AES128Encrypt (DEST, UnwrappedKey) ;
                RFLAGS.ZF := 0;
          FI;
FI;
RFLAGS.OF, SF, AF, PF, CF := 0;

Flags affected#

ZF is set to 0 if the operation succeeded and set to 1 if the operation failed due to a handle violation. The other arithmetic flags (OF, SF, AF, PF, CF) are cleared to 0.

Intel C/C++ compiler intrinsics#

AESENC128KL unsigned char _mm_aesenc128kl_u8(__m128i* odata, __m128i idata, const void* h);

Exceptions

Sources

• This instruction in the Intel manual
• Latency and throughput per microarchitecture