// This file was extracted from the TCG Published
// Trusted Platform Module Library
// Part 3: Commands
// Family "2.0"
// Level 00 Revision 01.16
// October 30, 2014
#include "InternalRoutines.h"
#include "Sign_fp.h"
#include "Attest_spt_fp.h"
//
//
// Error Returns Meaning
//
// TPM_RC_BINDING The public and private portions of the key are not properly bound.
// TPM_RC_KEY signHandle does not reference a signing key;
// TPM_RC_SCHEME the scheme is not compatible with sign key type, or input scheme is
// not compatible with default scheme, or the chosen scheme is not a
// valid sign scheme
// TPM_RC_TICKET validation is not a valid ticket
// TPM_RC_VALUE the value to sign is larger than allowed for the type of keyHandle
//
TPM_RC
TPM2_Sign(
Sign_In *in, // IN: input parameter list
Sign_Out *out // OUT: output parameter list
)
{
TPM_RC result;
TPMT_TK_HASHCHECK ticket;
OBJECT *signKey;
// Input Validation
// Get sign key pointer
signKey = ObjectGet(in->keyHandle);
// pick a scheme for sign. If the input sign scheme is not compatible with
// the default scheme, return an error.
result = CryptSelectSignScheme(in->keyHandle, &in->inScheme);
if(result != TPM_RC_SUCCESS)
{
if(result == TPM_RC_KEY)
return TPM_RC_KEY + RC_Sign_keyHandle;
else
return RcSafeAddToResult(result, RC_Sign_inScheme);
}
// If validation is provided, or the key is restricted, check the ticket
if( in->validation.digest.t.size != 0
|| signKey->publicArea.objectAttributes.restricted == SET)
{
// Compute and compare ticket
TicketComputeHashCheck(in->validation.hierarchy,
in->inScheme.details.any.hashAlg,
&in->digest, &ticket);
if(!Memory2BEqual(&in->validation.digest.b, &ticket.digest.b))
return TPM_RC_TICKET + RC_Sign_validation;
}
else
// If we don't have a ticket, at least verify that the provided 'digest'
// is the size of the scheme hashAlg digest.
// NOTE: this does not guarantee that the 'digest' is actually produced using
// the indicated hash algorithm, but at least it might be.
{
if( in->digest.t.size
!= CryptGetHashDigestSize(in->inScheme.details.any.hashAlg))
return TPM_RC_SIZE + RC_Sign_digest;
}
// Command Output
// Sign the hash. A TPM_RC_VALUE or TPM_RC_SCHEME
// error may be returned at this point
result = CryptSign(in->keyHandle, &in->inScheme, &in->digest, &out->signature);
return result;
}