---
name: "Tspi_EncodeDER_TssBlob"
section: "3"
platform: "linux"
package: "libtspi-dev"
version: "0.3.15-0.4"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Tspi_EncodeDER_TssBlob"
---

# Tspi\_EncodeDER\_TssBlob(3)

generate a DER encoded TSS blob.

## NAME

Tspi\_EncodeDER\_TssBlob - generate a DER encoded TSS blob.

## SYNOPSIS

```
#include <tss/tspi.h>

TSS_RESULT Tspi_EncodeDER_TssBlob(UINT32 rawBlobSize, BYTE*   rawBlob,
                                  UINT32 blobType,    UINT32* derBlobSize,
                                  BYTE*  derBlob);
```

## DESCRIPTION

**Tspi\_EncodeDER\_TssBlob**  is used to generate a DER-encoded blob in accordance with the ASN.1 data definitions in the Portable Data section of the Trusted Computing Group Software Stack Specification Version 1.2.

## PARAMETERS

### rawBlobSize

Size of the unwrapped blob.

### rawBlob

Pointer to the unwrapped blob.

### blobType

Type of blob being wrapped (refer to the TSS\_BLOB\_TYPE\_\* constants).

### derBlobSize

Pointer to the size of the derBlob buffer.  On input this parameter contains a pointer to the maximum size of the supplied derBlob buffer.  On output this parameter contains a pointer to the actual size of the DER-encoded blob.  On input, if this parameter points to a value of 0, then this function will return the size of the buffer required to hold the DER-encoded blob without writing to the derBlob buffer.

**Note:** If the raw data blob length is less than 2^16 bytes then the DER-encoding may add no more than 20 bytes.

### derBlob

Pointer to a buffer to hold the DER-encoded blob.

## RETURN CODES

**Tspi\_EncodeDER\_TssBlob** returns TSS\_SUCCESS on success, otherwise one of the following values are returned:

- TSS\_E\_BAD\_PARAMETER

  - TSS\_E\_INTERNAL\_ERROR - An error occurred internal to the TSS.

  ## CONFORMING TO

**Tspi\_EncodeDER\_TssBlob** conforms to the Trusted Computing Group Software Specification Version 1.2

## SEE ALSO

[**Tspi\_DecodeBER\_TssBlob**(3)](/Tspi_DecodeBER_TssBlob/3.md).