(mozilla-projects-nss-reference-fc-decryptverifyupdate)=

# FC_DecryptVerifyUpdate

## [Name](#name)

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FC_DecryptVerifyUpdate - continue a multi-part decrypt and verify operation
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## [Syntax](#syntax)

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```{code}
CK_RV FC_DecryptVerifyUpdate(
  CK_SESSION_HANDLE hSession,
  CK_BYTE_PTR pEncryptedData,
  CK_ULONG ulEncryptedDataLen,
  CK_BYTE_PTR pData,
  CK_ULONG_PTR pulDataLen
);
```

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## [Parameters](#parameters)

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`hSession`

: [in] session handle.

`pEncryptedData`

: [in] pointer to the encrypted data part.

`ulEncryptedDataLen`

: [in] length of encrypted data in bytes.

`pData`

: [in] pointer to the location which receives the recovered data part or NULL.

`pulDataLen`

: [in] pointer to the length of the recovered part buffer.
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## [Description](#description)

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`FC_DecryptVerifyUpdate` continues a multi-part decryption and signature verification
operation. After calling both `FC_DecryptInit` and `FC_VerifyInit` to set up the operations
this function may be called multiple times. The operation is finished by calls to
`FC_DecryptFinal` and `FC_VerifyFinal`.

A user must log into the token (to assume the NSS User role) before calling
`FC_DecryptVerifyUpdate`.
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## [Return value](#return_value)

## [Examples](#examples)

## [See also](#see_also)

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- [NSC_DecryptVerifyUpdate](/en-US/NSC_DecryptVerifyUpdate)
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