Add extend_rtmr3 in tdx-attest

Author: kvinwang

tdx-attest/src/lib.rs

@@ -20,3 +20,14 @@ pub type TdxReportData = [u8; 64];
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct TdxReport(pub [u8; 1024]);
+
+pub fn extend_rtmr3(event: &str, payload: &[u8]) -> anyhow::Result<()> {
+    use anyhow::Context;
+    // This code is not defined in the TCG specification.
+    // See https://trustedcomputinggroup.org/wp-content/uploads/PC-ClientSpecific_Platform_Profile_for_TPM_2p0_Systems_v51.pdf
+    let event_type = 0x08000001;
+    let index = 3;
+    let log = eventlog::TdxEventLog::new(index, event_type, event.to_string(), payload.to_vec());
+    extend_rtmr(index, event_type, log.digest).context("Failed to extend RTMR")?;
+    log_rtmr_event(&log).context("Failed to log RTMR event")
+}