X509_verify gives error "tpm2::cannot duplicate context" on Windows

[philippun1]

Hi,

if I try to verify a X509 certificate with the tpm2 provider I get the following error output:

PROVIDER INIT
Loaded tpm2 provider
Loaded default provider
DER DECODER DECODE
TSS2 DECODER DECODE 0x87
TSS2 DECODER LOAD parent: primary 0x40000001
TSS2 DECODER DECODE 0x87
TSS2 DECODER LOAD parent: primary 0x40000001
TSS2 DECODER DECODE 0x87
TSS2 DECODER LOAD parent: primary 0x40000001
TSS2 DECODER DECODE found RSA
RSA LOAD
RSA GET_PARAMS [ bits security-bits max-size ]
RSA HAS 85
SIGN DIGEST_INIT rsa MD=SHA256
SIGN DIGEST_START
SIGN DIGEST_UPDATE
ERROR:esys:api\Esys_ContextSave.c:251:Esys_ContextSave_Finish() Received a non-TPM Error
ERROR:esys:api\Esys_ContextSave.c:92:Esys_ContextSave() Esys Finish ErrorCode (0x80280400)
ERROR:esys:esys_iutil.c:1218:iesys_check_sequence_async() Esys called in bad sequence.
ERROR:esys:api\Esys_FlushContext.c:66:Esys_FlushContext() Error in async function ErrorCode (0x00070007)
verify x509 failed: error:40000013:tpm2::cannot duplicate context
RSA FREE
ERROR:esys:esys_iutil.c:1218:iesys_check_sequence_async() Esys called in bad sequence.
ERROR:esys:api\Esys_FlushContext.c:66:Esys_FlushContext() Error in async function ErrorCode (0x00070007)

There is no difference if I use a certificate created programmatically or via openssl.exe. I use the following command to create my certificate:
openssl req -provider-path . -provider tpm2 -provider default -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -sha256 -days 365

This is the stack when the error happens:

And this is the exact position in the tpm code, Tss2_Sys_Execute.c line 140 in function Tss2_Sys_ExecuteFinish:

I have tested the same code in a Ubuntu VM (simulated TPM2) with the tpm2-openssl package and the verify works as expected.

[philippun1]

Any tips or hints on where to look so I can debug into this more efficiently? Thanks.

If I do not use the tpm2 provider on client side, I get a salt length check failure, see #75

[gotthardp]

Please see #38. It seems that microsoft may be blocking some TPM functions. See here.

[philippun1]

Ok, thanks for the info.

The tpm2 provider can just be unloaded to perform the verify and loaded again afterwards, which is fine for my use case. So I will close this issue.