Vol. 3D 41-95

SGX INSTRUCTION REFERENCES

EREPORT—Create a Cryptographic Report of the Enclave 

Instruction Operand Encoding

Description

This leaf function creates a cryptographic REPORT that describes the contents of the enclave. This instruction leaf 
can only be executed when inside the enclave. The cryptographic report can be used by other enclaves to deter-
mine that the enclave is running on the same platform.
RBX contains the effective address of the MRENCLAVE value of the enclave that will authenticate the REPORT 
output, using the REPORT key delivered by EGETKEY command for that enclave. RCX contains the effective address 
of a 64-byte REPORTDATA structure, which allows the caller of the instruction to associate data with the enclave 
from which the instruction is called. RDX contains the address where the REPORT will be output by the instruction.

EREPORT Memory Parameter Semantics

This instruction leaf perform the following: 
1. Validate the 3 operands (RBX, RCX, RDX) are inside the enclave.
2. Compute a report key for the target enclave, as indicated by the value located in RBX(TARGETINFO).
3. Assemble the enclave SECS data to complete the REPORT structure (including the data provided using the RCX 

(REPORTDATA) operand).

4. Computes a crytpographic hash over REPORT structure.
5. Add the computed hash to the REPORT structure.
6. Output the completed REPORT structure to the address in RDX (OUTPUTDATA). 
The instruction fails if the operands are not properly aligned.
CR_REPORT_KEYID, used to provide key wearout protection, is populated with a statistically unique value on boot 
of the platform by a trusted entity within the SGX TCB.

The instruction faults if any of the following: 

Opcode/

Instruction

Op/En

64/32 

bit Mode 

Support

CPUID 

Feature 

Flag

Description

 EAX = 00H

IR

V/V

SGX1

This leaf function creates a cryptographic report of the enclave.

ENCLU[EREPORT]

Op/En

EAX

RBX

RCX

RDX

IR

EREPORT (In)

Address of TARGETINFO 

(In)

Address of REPORTDATA 

(In)

Address where the REPORT is 

written to in an OUTPUTDATA (In)

TARGETINFO

REPORTDATA

OUTPUTDATA

Read access by Enclave 

Read access by Enclave 

Read/Write access by Enclave