wasm-micro-runtime/samples/sgx-ra/wasm-app/main.c
Jämes Ménétrey 8b8c59589d
Clarify how to verify SGX evidence without an Intel SGX-enabled platform (#3158)
This PR encompasses two complementing purposes:

A documentation on verifying an Intel SGX evidence as produced by WAMR,
including a guide for verification without an Intel SGX-enabled platform.
This also contains a small addition to the RA sample to extract specific
information, such as whether the enclave is running in debug mode.

A C# sample to verify evidence on trusted premises (and without Intel SGX).
Evidence is generated on untrusted environments, using Intel SGX.
2024-02-17 18:44:22 +08:00

132 lines
3.9 KiB
C

/*
* Copyright (c) 2022 Intel Corporation
* Copyright (c) 2020-2021 Alibaba Cloud
*
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*/
#include <stdio.h>
#include <stdlib.h>
#include "lib_rats_wrapper.h"
#define __is_print(ch) ((unsigned int)((ch) - ' ') < 127u - ' ')
/**
* hex_dump
*
* @brief dump data in hex format
*
* @param title: Title
* @param buf: User buffer
* @param size: Dump data size
* @param number: The number of outputs per line
*
* @return void
*/
void
hex_dump(const char *title, const uint8_t *buf, uint32_t size, uint32_t number)
{
int i, j;
if (title) {
printf("\n\t%s:\n\n", title);
}
for (i = 0; i < size; i += number) {
printf("%08X: ", i);
for (j = 0; j < number; j++) {
if (j % 8 == 0) {
printf(" ");
}
if (i + j < size)
printf("%02X ", buf[i + j]);
else
printf(" ");
}
printf(" ");
for (j = 0; j < number; j++) {
if (i + j < size) {
printf("%c", __is_print(buf[i + j]) ? buf[i + j] : '.');
}
}
printf("\n");
}
}
int
main(int argc, char **argv)
{
int ret_code = -1;
char *evidence_json = NULL;
// Generate user_data by SHA256 buffer and the wasm module.
// user_data = SHA256(sha256_wasm_module || buffer)
const char *buffer = "This is a sample.";
// If you want to declare the evidence of type rats_sgx_evidence_t on the
// stack, you should modify the stack size of the CMAKE_EXE_LINKER_FLAGS in
// CMakeLists.txt to 51200 at least.
rats_sgx_evidence_t *evidence =
(rats_sgx_evidence_t *)malloc(sizeof(rats_sgx_evidence_t));
if (!evidence) {
printf("ERROR: No memory to allocate.\n");
goto err;
}
int rats_err = librats_collect(&evidence_json, buffer);
if (rats_err != 0) {
printf("ERROR: Collect evidence failed, error code: %#x\n", rats_err);
goto err;
}
if (librats_parse_evidence(evidence_json, evidence) != 0) {
printf("ERROR: Parse evidence failed.\n");
goto err;
}
// You could use these parameters for further verification.
hex_dump("Quote", evidence->quote, evidence->quote_size, 32);
hex_dump("User Data", evidence->user_data, SGX_USER_DATA_SIZE, 32);
hex_dump("MRENCLAVE", evidence->mr_enclave, SGX_MEASUREMENT_SIZE, 32);
hex_dump("MRSIGNER", evidence->mr_signer, SGX_MEASUREMENT_SIZE, 32);
printf("\n\tProduct ID:\t\t\t\t%u\n", evidence->product_id);
printf("\tSecurity Version:\t\t\t%u\n", evidence->security_version);
printf("\tAttributes.flags:\t\t\t%llu\n", evidence->att_flags);
printf("\tAttributes.flags[INITTED]:\t\t%d\n",
(evidence->att_flags & SGX_FLAGS_INITTED) != 0);
printf("\tAttributes.flags[DEBUG]:\t\t%d\n",
(evidence->att_flags & SGX_FLAGS_DEBUG) != 0);
printf("\tAttributes.flags[MODE64BIT]:\t\t%d\n",
(evidence->att_flags & SGX_FLAGS_MODE64BIT) != 0);
printf("\tAttributes.flags[PROVISION_KEY]:\t%d\n",
(evidence->att_flags & SGX_FLAGS_PROVISION_KEY) != 0);
printf("\tAttributes.flags[EINITTOKEN_KEY]:\t%d\n",
(evidence->att_flags & SGX_FLAGS_EINITTOKEN_KEY) != 0);
printf("\tAttributes.flags[KSS]:\t\t\t%d\n",
(evidence->att_flags & SGX_FLAGS_KSS) != 0);
printf("\tAttributes.flags[AEX_NOTIFY]:\t\t%d\n",
(evidence->att_flags & SGX_FLAGS_AEX_NOTIFY) != 0);
printf("\tAttribute.xfrm:\t\t\t\t%llu\n", evidence->att_xfrm);
rats_err = librats_verify((const char *)evidence_json, evidence->user_data);
if (rats_err != 0) {
printf("ERROR: Evidence is not trusted, error code: %#x.\n", rats_err);
goto err;
}
ret_code = 0;
printf("Evidence is trusted.\n");
err:
if (evidence_json) {
librats_dispose_evidence_json(evidence_json);
}
if (evidence) {
free(evidence);
}
return ret_code;
}