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

# FC_WrapKey

## [Name](#name)

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FC_WrapKey - wrap a key
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## [Syntax](#syntax)

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```{code}
CK_RV FC_WrapKey(
  CK_SESSION_HANDLE hSession,
  CK_MECHANISM_PTR pMechanism,
  CK_OBJECT_HANDLE hWrappingKey,
  CK_OBJECT_HANDLE hKey,
  CK_BYTE_PTR pWrappedKey,
  CK_ULONG_PTR pusWrappedKeyLen
);
```

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## [Parameters](#parameters)

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`hSession`

: [in] session handle.

`pMechanism`

: [in] pointer to the mechanism to use.

`hWrappingKey`

: [in] pointer to the public key template.

`hKey`

: [in] number of attributes in the public key template.

`pWrappedKey`

: [out] pointer to the location to receive the wrapped key or NULL.

`pusWrappedKeyLen`

: [in, out] pointer to length of wrapped key buffer.
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## [Description](#description)

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`FC_WrapKey` wraps (encrypts) a key. If `pWrappedKey` is NULL the length of the wrapped key
is returned in `pusWrappedKeyLen` and FC_WrapKey may be called again with `pWrappedKey` set
to retrieve the wrapped key.

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

## [Examples](#examples)

## [See also](#see_also)

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