On Wed, Apr 12, 2023 at 8:42 PM Kuppuswamy Sathyanarayanan sathyanarayanan.kuppuswamy@linux.intel.com wrote:
In TDX guest, the second stage of the attestation process is Quote generation. This process is required to convert the locally generated TDREPORT into a remotely verifiable Quote. It involves sending the TDREPORT data to a Quoting Enclave (QE) which will verify the integerity of the TDREPORT and sign it with an attestation key.
nit: integrity
Intel's TDX attestation driver exposes TDX_CMD_GET_QUOTE IOCTL to allow user agent get the TD Quote.
nit: to get
Add a kernel selftest module to verify the Quote generation feature.
TD Quote generation involves following steps:
- Get the TDREPORT data using TDX_CMD_GET_REPORT IOCTL.
- Embed the TDREPORT data in quote buffer and request for quote generation via TDX_CMD_GET_QUOTE IOCTL request.
- Upon completion of the GetQuote request, check for non zero value in the status field of Quote header to make sure the generated quote is valid.
Reviewed-by: Tony Luck tony.luck@intel.com Reviewed-by: Andi Kleen ak@linux.intel.com Reviewed-by: Shuah Khan skhan@linuxfoundation.org Reviewed-by: Mika Westerberg mika.westerberg@linux.intel.com Acked-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Signed-off-by: Kuppuswamy Sathyanarayanan sathyanarayanan.kuppuswamy@linux.intel.com
tools/testing/selftests/tdx/tdx_guest_test.c | 68 ++++++++++++++++++-- 1 file changed, 62 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/tdx/tdx_guest_test.c b/tools/testing/selftests/tdx/tdx_guest_test.c index 81d8cb88ea1a..2eccde54185b 100644 --- a/tools/testing/selftests/tdx/tdx_guest_test.c +++ b/tools/testing/selftests/tdx/tdx_guest_test.c @@ -18,6 +18,7 @@ #define TDX_GUEST_DEVNAME "/dev/tdx_guest" #define HEX_DUMP_SIZE 8 #define DEBUG 0 +#define QUOTE_SIZE 8192
/**
- struct tdreport_type - Type header of TDREPORT_STRUCT.
@@ -128,21 +129,29 @@ static void print_array_hex(const char *title, const char *prefix_str, printf("\n"); }
+/* Helper function to get TDREPORT */ +long get_tdreport0(int devfd, struct tdx_report_req *req) +{
int i;/* Generate sample report data */for (i = 0; i < TDX_REPORTDATA_LEN; i++)req->reportdata[i] = i;
Shouldn't req be zeroed before populating reportdata? We wouldn't want uninitialized memory to leave the guest. I know this is just a test, but it's best to model good practices for anyone that might copy/paste.
return ioctl(devfd, TDX_CMD_GET_REPORT0, req);+}
TEST(verify_report) { struct tdx_report_req req; struct tdreport *tdreport;
int devfd, i;
int devfd; devfd = open(TDX_GUEST_DEVNAME, O_RDWR | O_SYNC); ASSERT_LT(0, devfd);
/* Generate sample report data */for (i = 0; i < TDX_REPORTDATA_LEN; i++)req.reportdata[i] = i;/* Get TDREPORT */ASSERT_EQ(0, ioctl(devfd, TDX_CMD_GET_REPORT0, &req));
ASSERT_EQ(0, get_tdreport0(devfd, &req)); if (DEBUG) { print_array_hex("\n\t\tTDX report data\n", "",@@ -160,4 +169,51 @@ TEST(verify_report) ASSERT_EQ(0, close(devfd)); }
+TEST(verify_quote) +{
struct tdx_quote_hdr *quote_hdr;struct tdx_report_req rep_req;struct tdx_quote_req req;__u64 quote_buf_size;__u8 *quote_buf;int devfd;/* Open attestation device */devfd = open(TDX_GUEST_DEVNAME, O_RDWR | O_SYNC);ASSERT_LT(0, devfd);/* Add size for quote header */quote_buf_size = sizeof(*quote_hdr) + QUOTE_SIZE;/* Allocate quote buffer */quote_buf = malloc(quote_buf_size);ASSERT_NE(NULL, quote_buf);quote_hdr = (struct tdx_quote_hdr *)quote_buf;/* Initialize GetQuote header */quote_hdr->version = 1;quote_hdr->status = GET_QUOTE_SUCCESS;quote_hdr->in_len = TDX_REPORT_LEN;quote_hdr->out_len = 0;/* Get TDREPORT data */ASSERT_EQ(0, get_tdreport0(devfd, &rep_req));/* Fill GetQuote request */memcpy(quote_hdr->data, rep_req.tdreport, TDX_REPORT_LEN);req.buf = (__u64)quote_buf;req.len = quote_buf_size;ASSERT_EQ(0, ioctl(devfd, TDX_CMD_GET_QUOTE, &req));/* Check whether GetQuote request is successful */EXPECT_EQ(0, quote_hdr->status);free(quote_buf);ASSERT_EQ(0, close(devfd));+}
TEST_HARNESS_MAIN
2.34.1