---
name: "Tspi_DAA_VerifySignature"
section: "3"
platform: "linux"
package: "libtspi-dev"
version: "0.3.9-3+wheezy1"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/Tspi_DAA_VerifySignature"
---

# Tspi\_DAA\_VerifySignature(3)

creates a challenge for the TCG platform

TCG Software Stack Developer's Reference

## NAME

Tspi\_DAA\_VerifySignature - creates a challenge for the TCG platform

## SYNOPSIS

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

TSPICALL Tspi_DAA_VerifySignature(
    TSS_HDAA                    hDAA,
    TSS_DAA_SIGNATURE           daaSignature,
    TSS_HKEY                    hPubKeyIssuer,
    TSS_DAA_SIGN_DATA           signData,
    UINT32                      attributesLength,
    BYTE**                      attributes,
    UINT32                      nonceVerifierLength,
    BYTE*                       nonceVerifier,
    UINT32                      baseNameLength,
    BYTE*                       baseName,
    TSS_BOOL*                   isCorrect
);
```

## DESCRIPTION

Tspi\_DAA\_VerifySignature is part of the DAA Verifier component. It's the last function out of 2 in order to verify a DAA Credential of a TCG platform. It verifies the DAA Credential and detects public rogue TPMs. This is an optional function and does not require a TPM or a TCS.

## PARAMETERS

### hDAA

The *hDAA* parameter is used to specify the handle of the DAA object.

### daaSignature

The *daaSignature* parameter is the DAA signature contains proof of ownership of the DAA Credential, as well as a signature on either an AIK or a message.

### hPubKeyIssuer

The *hPubKeyIssuer* parameter is the handle of the DAA public key of the DAA Issuer of the credential.

### signData

The *signData* parameter defines what data is signed (AIK or message).

### attributesLength

The *attributesLength* parameter is the Length of attributes array that is determined by the DAA Issuer public key (lh+li). The length of a single attribute is lf/8.

### attributes

The *attributes* parameter is the array of attributes which the DAA Credential owner reveals.

### nonceVerifierLength

The *nonceVerifierLength* parameter is the length of nonceVerifier (20 bytes).

### nonceVerifier

The *nonceVerifier* parameter is the nonce that was computed in the previous function (Tspi\_VerifyInit).

### baseNameLength

The *baseNameLength* parameter the length of the baseName.

### baseName

The *baseName* parameter is the base name that was chosen for the DAA Signature.

### isCorrect

The *isCorrect* parameter denotes if the verification of the DAA Signature was successful.

## RETURN CODES

**Tspi\_DAA\_VerifySignature** returns TSS\_SUCCESS on success, otherwise one of the following values is returned:

- TSS\_E\_BAD\_PARAMETER

  - TSS\_E\_INTERNAL\_ERROR

  An internal SW error has been detected.

- **Tspi\_DAA\_VerifySignature** conforms to the Trusted Computing Group

  ## CONFORMING TO

Software Specification version 1.2

## SEE ALSO

[**Tspi\_DAA\_IssuerKeyVerification**(3)](/Tspi_DAA_IssuerKeyVerification/3.md)