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 integrity of the TDREPORT and sign it with an attestation key.
Intel's TDX attestation driver exposes TDX_CMD_GET_QUOTE IOCTL to allow the user agent to get the TD Quote.
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 Reviewed-by: Erdem Aktas erdemaktas@google.com Acked-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Signed-off-by: Kuppuswamy Sathyanarayanan sathyanarayanan.kuppuswamy@linux.intel.com ---
Changes since v2: * Adapted to struct tdx_quote_hdr -> struct tdx_quote_buf rename.
tools/testing/selftests/tdx/tdx_guest_test.c | 65 ++++++++++++++++++-- 1 file changed, 59 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..0b4b4293b9cb 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; + + 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 +169,48 @@ TEST(verify_report) ASSERT_EQ(0, close(devfd)); }
+TEST(verify_quote) +{ + struct tdx_quote_buf *quote_buf; + struct tdx_report_req rep_req; + struct tdx_quote_req req; + __u64 quote_buf_size; + 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_buf) + QUOTE_SIZE; + + /* Allocate quote buffer */ + quote_buf = (struct tdx_quote_buf *)malloc(quote_buf_size); + ASSERT_NE(NULL, quote_buf); + + /* Initialize GetQuote header */ + quote_buf->version = 1; + quote_buf->status = GET_QUOTE_SUCCESS; + quote_buf->in_len = TDX_REPORT_LEN; + quote_buf->out_len = 0; + + /* Get TDREPORT data */ + ASSERT_EQ(0, get_tdreport0(devfd, &rep_req)); + + /* Fill GetQuote request */ + memcpy(quote_buf->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_buf->status); + + free(quote_buf); + + ASSERT_EQ(0, close(devfd)); +} + TEST_HARNESS_MAIN