5.5.2.6 Crypto_Aead_AesGcm_DecryptAuthDirect

crypto_Aead_Status_E Crypto_Aead_AesGcm_DecryptAuthDirect(
    crypto_HandlerType_E handlerType_en, 
    uint8_t *ptr_inputData, 
    uint32_t dataLen, 
    uint8_t *ptr_outData, 
    uint8_t *ptr_key, 
    uint32_t keyLen, 
    uint8_t *ptr_initVect,
    uint32_t initVectLen
    uint8_t *ptr_aad, 
    uint32_t aadLen, 
    uint8_t *ptr_authTag, 
    uint32_t authTagLen, 
    uint32_t sessionID
    );

Description

This API performs AES_EAX decryption and authenticates using authentication tag in a single step without initializing.

Parameters


No.	Argument Type	Argument Name	Type	Description
1	crypto_HandlerType_E	handlerType_en	Input	Enum for crypto operation handler i.e., SW, HW.
2	uint8_t*	ptr_inputData	Input	Input data to decrypt.
3	uint32_t	dataLen	Input	Input length of plain data in bytes.
4	uint8_t*	ptr_outData	Output	Pointer to store plain text as output.
5	uint8_t*	ptr_key	Input	Key for the AES-GCM cipher operation.
6	uint32_t	keyLen	Input	Key length in bytes for the AES-GCM algorithm.
7	uint8_t*	ptr_initVect	Input	Pointer for the IV Value
8	uint32_t	initVectLen	Input	Length of IV in bytes
9	uint8_t*	ptr_aad	Input	Pointer for additional authentication data. It is optional to use, so it can be NULL also.
10	uint32_t	aadLen	Input	Length of additional authentication data, as it is optional so it can be 0 also.
11	uint8_t*	ptr_authTag	Input	Pointer for authentication tag.
12	uint8_t*	authTagLen	Input	Authentication tag length in bytes, range 12-16 bytes.
13	uint32_t	sessionID	Input	It defines the session ID, must be more than zero.

Returns


Return Type	Description
crypto_Aead_Status_E	Function returns the status of the API.

Example

#define sessionID 1
crypto_Aead_Status_E status;
crypto_HandlerType_E handlerType_en = CRYPTO_HANDLER_HW_INTERNAL;
uint8_t inputData[32] = {/*data*/};
uint32_t dataLen = sizeof(inputData);
uint8_t key[32] = {/*data*/};
uint32_t keyLen = sizeof(key);
uint8_t outData[64];
uint32_t digestLen = sizeof(outData);
uint8_t initVect[32] = {/*data*/};
uint32_t initVectLen = sizeof(initVect);
uint8_t authTag[32] = {/*data*/};
uint32_t authTagLen = 16; //auth tag length 12-16 bytes
uint8_t aad[32] = {/*data*/};
uint32_t aadLen = sizeof(aad);

status = Crypto_Aead_AesGcm_DecryptAuthDirect(
    handlerType_en,
    inputData,
    dataLen,
    outData,
    key,
    keyLen,
    initVect,
    initVectLen,
    aad,    
    aadLen,
    authTag,
    authTagLen,
    sessionID
);