[xen staging] vtpmmgr: Allow specifying srk_handle for TPM2

[patchbot@xxxxxxx]

commit 3f1b5080d64d2b66a686133e9f24998a3609d1a3
Author:     Jason Andryuk <jandryuk@xxxxxxxxx>
AuthorDate: Thu May 6 09:59:14 2021 -0400
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Mon May 10 14:48:13 2021 +0100

    vtpmmgr: Allow specifying srk_handle for TPM2
    
    Bypass taking ownership of the TPM2 if an srk_handle is specified.
    
    This srk_handle must be usable with Null auth for the time being.
    
    Signed-off-by: Jason Andryuk <jandryuk@xxxxxxxxx>
    Reviewed-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>
    Reviewed-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
---
 docs/man/xen-vtpmmgr.7.pod |  7 +++++++
 stubdom/vtpmmgr/init.c     | 11 ++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/docs/man/xen-vtpmmgr.7.pod b/docs/man/xen-vtpmmgr.7.pod
index 875dcce508..3286954568 100644
--- a/docs/man/xen-vtpmmgr.7.pod
+++ b/docs/man/xen-vtpmmgr.7.pod
@@ -92,6 +92,13 @@ Valid arguments:
 
 =over 4
 
+=item srk_handle=<HANDLE>
+
+Specify a srk_handle for TPM 2.0.  TPM 2.0 uses a key hierarchy, and
+this allow specifying the parent handle for vtpmmgr to create its own
+key under.  Using this option bypasses vtpmmgr trying to take ownership
+of the TPM.
+
 =item owner_auth=<AUTHSPEC>
 
 =item srk_auth=<AUTHSPEC>
diff --git a/stubdom/vtpmmgr/init.c b/stubdom/vtpmmgr/init.c
index 2d314d98e8..decf8e8b4d 100644
--- a/stubdom/vtpmmgr/init.c
+++ b/stubdom/vtpmmgr/init.c
@@ -302,6 +302,11 @@ int parse_cmdline_opts(int argc, char** argv, struct Opts* 
opts)
             goto err_invalid;
          }
       }
+      else if(!strncmp(argv[i], "srk_handle=", 11)) {
+         if(sscanf(argv[i] + 11, "%x", &vtpm_globals.srk_handle) != 1) {
+            goto err_invalid;
+         }
+      }
       else if(!strncmp(argv[i], "tpmdriver=", 10)) {
          if(!strcmp(argv[i] + 10, "tpm_tis")) {
             opts->tpmdriver = TPMDRV_TPM_TIS;
@@ -572,7 +577,11 @@ TPM_RESULT vtpmmgr2_create(void)
 {
     TPM_RESULT status = TPM_SUCCESS;
 
-    TPMTRYRETURN(tpm2_take_ownership());
+    if ( vtpm_globals.srk_handle == 0 ) {
+        TPMTRYRETURN(tpm2_take_ownership());
+    } else {
+        tpm2_AuthArea_ctor(NULL, 0, &vtpm_globals.srk_auth_area);
+    }
 
    /* create SK */
     TPM2_Create_Params_out out;
--
generated by git-patchbot for /home/xen/git/xen.git#staging