.\" Copyright (C) 2004 International Business Machines Corporation
.\" Written by Kathy Robertson based on the Trusted Computing Group Software Stack Specification Version 1.1 Golden
.\"
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.TH "Tspi_Data_Unseal" 3 "2004-05-26" "TSS 1.1" "TCG Software Stack Developer's Reference"
.SH NAME
Tspi_Data_Unseal \- dencrypt data encrypted by Tspi_Data_Seal() only if it was encrypted on the same platform and under the current configuration.
.SH "SYNOPSIS"
.ad l
.hy 0
.nf
.B #include <tss/platform.h>
.B #include <tss/tcpa_defines.h>
.B #include <tss/tcpa_typedef.h>
.B #include <tss/tcpa_struct.h>
.B #include <tss/tss_typedef.h>
.B #include <tss/tss_structs.h>
.B #include <tss/tspi.h>
.sp
.BI "TSS_RESULT Tspi_Data_Unseal(TSS_HENCDATA " hEncData ",              TSS_HKEY " hKey ","
.BI "                            UINT32       " pulUnsealedDataLength ", BYTE**   " prgbUnsealedData ");"
.fi
.sp
.ad
.hy

.SH "DESCRIPTION"
.PP
\fBTspi_Data_Unseal\fR reveals data encrypted by the Tspi_Data_Seal only if it was encrypted on the same platform and the current configuration. This is internally proofed and guaranteed by the TPM.
.SH "PARAMETERS"
.PP
.SS hEncData
Handle of the data object which contains the sealed data.
.PP
.SS hKey
Handle to the key object addressing the nonmigratable key which is used to decrypt the data.
.PP
.SS pulUnsealedDataLength
The length (in bytes) of the prgbUnsealedData parameter.
.PP
.SS prgbUnsealedData
On successful completion of the command, this parameter points to a buffer containing the plaintext data.
.PP
.SS hPcrComposite
Handle of the PCR Composite object specifying the PCRs which are part of the sealed data blob. Set to NULL, if the encrypted data should only be bound to the system and PCRs are not of interest.
.SH "RETURN CODES"
.PP
\fBTspi_Data_Unseal\fR returns TSS_SUCCESS on success, otherwise one of the following values are returned:
.TP
.SM TSS_E_INVALID_HANDLE - Either \fBhEncData\fR or \fBhKey\fR is not a valid handle.
.TP
.SM TSS_E_INTERNAL_ERROR - An error occurred internal to the TSS.

.SH "CONFORMING TO"

.PP
\fBTspi_Data_Unseal\fR conforms to the Trusted Computing Group Software Specification version 1.1 Golden
.SH "SEE ALSO"

.PP
\fBTspi_Data_Seal\fR(3).