Vol. 3D 41-67

SGX INSTRUCTION REFERENCES

IF (DS:RCX does not resolve within an EPC) 

THEN #PF(DS:RCX); FI;

(* Check that the combination of requested PT, PENDING and MODIFIED is legal *)
IF (NOT ( ((SCRATCH_SECINFO.FLAGS.PT is PT_REG) and (SCRATCH_SECINFO.FLAGS.MODIFIED is 0)) or

((SCRATCH_SECINFO.FLAGS.PT is PT_TCS or PT_TRIM) and (SCRATCH_SECINFO.FLAGS.PENDING is 0) and
(SCRATCH_SECINFO.FLAGS.MODIFIED is 1)) ) )

THEN #GP(0); FI

(* Check security attributes of the destination EPC page *)
If ( (EPCM(DS:RCX).VALID is 0) or (EPCM(DS:RCX).BLOCKED is not 0) or

((EPCM(DS:RCX).PT is not PT_REG) and (EPCM(DS:RCX).PT is not PT_TCS) and (EPCM(DS:RCX).PT is not PT_TRIM)) or
(EPCM(DS:RCX).ENCLAVESECS ≠ CR_ACTIVE_SECS))
THEN #PF((DS:RCX); FI;

(* Check the destination EPC page for concurrency *)
IF ( EPC page in use ) 

THEN #GP(0); FI;

(* Re-Check security attributes of the destination EPC page *)
IF ( (EPCM(DS:RCX).VALID is 0) or (EPCM(DS:RCX).ENCLAVESECS ≠ CR_ACTIVE_SECS) )

THEN #PF(DS:RCX); FI;

(* Verify that accept request matches current EPC page settings *)
IF ( (EPCM(DS:RCX).ENCLAVEADDRESS ≠ DS:RCX) or (EPCM(DS:RCX).PENDING ≠ SCRATCH_SECINFO.FLAGS.PENDING) or

(EPCM(DS:RCX).MODIFIED ≠ SCRATCH_SECINFO.FLAGS.MODIFIED) or (EPCM(DS:RCX).R ≠ SCRATCH_SECINFO.FLAGS.R) or
(EPCM(DS:RCX).W ≠ SCRATCH_SECINFO.FLAGS.W) or (EPCM(DS:RCX).X ≠ SCRATCH_SECINFO.FLAGS.X) or
(EPCM(DS:RCX).PT ≠ SCRATCH_SECINFO.FLAGS.PT) )
THEN

RFLAGS  1;
RAX  SGX_PAGE_ATTRIBUTES_MISMATCH;
GOTO DONE;

FI;
(* Check that all required threads have left enclave *)
IF (Tracking not correct)

THEN

RFLAGS.ZF  1;
RAX  SGX_NOT_TRACKED;
GOTO DONE;

FI;

(* Get pointer to the SECS to which the EPC page belongs *)
TMP_SECS = << Obtain physical address of SECS through EPCM(DS:RCX)>>
(* For TCS pages, perform additional checks *)
IF (SCRATCH_SECINFO.FLAGS.PT = PT_TCS) 

THEN

IF (DS:RCX.RESERVED ≠ 0) #GP(0); FI;

FI;

(* Check that TCS.FLAGS.DBGOPTIN, TCS stack, and TCS status are correctly initialized *)
IF ( ((DS:RCX).FLAGS.DBGOPTIN is not 0) or ((DS:RCX).CSSA 

≥

 (DS:RCX).NSSA) or ((DS:RCX).AEP is not 0) or ((DS:RCX).STATE is not 0) 

THEN #GP(0); FI;