SigV4_GenerateHTTPAuthorization

Generates the HTTP Authorization header value.

SigV4Status_t SigV4_GenerateHTTPAuthorization( const SigV4Parameters_t * pParams,
                                               char * pAuthBuf,
                                               size_t * authBufLen,
                                               char ** pSignature,
                                               size_t * signatureLen );

Note

The API does not support HTTP headers containing empty HTTP header keys or values.

Parameters

[in]	pParams	Parameters for generating the SigV4 signature.
[out]	pAuthBuf	Buffer to hold the generated Authorization header value.
[in,out]	authBufLen	Input: the length of pAuthBuf, output: the length of the authorization value written to the buffer.
[out]	pSignature	Location of the signature in the authorization string.
[out]	signatureLen	The length of pSignature.

Returns

SigV4Success if successful, error code otherwise.

Example

// The following example shows how to use the SigV4_GenerateHTTPAuthorization
// function to generate the HTTP Authorization header value for HTTP requests
// to AWS services requiring SigV4 authentication.
 
SigV4Status_t status = SigV4Success;
 
// Buffer to hold the authorization header.
char pSigv4Auth[ 2048U ];
size_t sigv4AuthLen = sizeof( pSigv4Auth );
 
// Pointer to signature in the Authorization header that will be populated in
// pSigv4Auth by the SigV4_GenerateHTTPAuthorization API function.
char * signature = NULL;
size_t signatureLen = 0;
 
SigV4Parameters_t sigv4Params =
{
    // Parsed temporary credentials obtained from AWS IoT Credential Provider.
    .pCredentials     = &sigv4Creds,
    // Date in ISO8601 format.
    .pDateIso8601     = pDateISO8601,
    // The AWS region for the request.
    .pRegion          = AWS_REGION,
    .regionLen        = strlen( AWS_REGION ),
    // The AWS service for the request.
    .pService         = AWS_SERVICE_NAME,
    .serviceLen       = strlen( AWS_SERVICE_NAME ),
    // SigV4 crypto interface. See SigV4CryptoInterface_t interface documentation.
    .pCryptoInterface = &cryptoInterface,
    // HTTP parameters for the HTTP request to generate a SigV4 authorization header for.
    .pHttpParameters  = &sigv4HttpParams
};
 
status = SigV4_GenerateHTTPAuthorization( &sigv4Params, pSigv4Auth, &sigv4AuthLen, &signature, &signatureLen );
 
if( status != SigV4Success )
{
   // Failed to generate authorization header.
}