path: root/doc/pkcs7-api.texi

@subheading gnutls_pkcs7_add_attr
@anchor{gnutls_pkcs7_add_attr}
@deftypefun {int} {gnutls_pkcs7_add_attr} (gnutls_pkcs7_attrs_t * @var{list}, const char * @var{oid}, gnutls_datum_t * @var{data}, unsigned @var{flags})
@var{list}: A list of existing attributes or pointer to @code{NULL}  for the first one

@var{oid}: the OID of the attribute to be set

@var{data}: the raw (DER-encoded) data of the attribute to be set

@var{flags}: zero or @code{GNUTLS_PKCS7_ATTR_ENCODE_OCTET_STRING} 

This function will set a PKCS @code{7}  attribute in the provided list.
If this function fails, the previous list would be deallocated.

Note that any attributes set with this function must either be
DER or BER encoded, unless a special flag is present.

@strong{Returns:} On success, the new list head, otherwise @code{NULL} .

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_attrs_deinit
@anchor{gnutls_pkcs7_attrs_deinit}
@deftypefun {void} {gnutls_pkcs7_attrs_deinit} (gnutls_pkcs7_attrs_t @var{list})
@var{list}: A list of existing attributes

This function will clear a PKCS @code{7}  attribute list.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_deinit
@anchor{gnutls_pkcs7_deinit}
@deftypefun {void} {gnutls_pkcs7_deinit} (gnutls_pkcs7_t @var{pkcs7})
@var{pkcs7}: the type to be deinitialized

This function will deinitialize a PKCS7 type.
@end deftypefun

@subheading gnutls_pkcs7_delete_crl
@anchor{gnutls_pkcs7_delete_crl}
@deftypefun {int} {gnutls_pkcs7_delete_crl} (gnutls_pkcs7_t @var{pkcs7}, int @var{indx})
@var{pkcs7}: The pkcs7 type

@var{indx}: the index of the crl to delete

This function will delete a crl from a PKCS7 or RFC2630 crl set.
Index starts from 0. Returns 0 on success.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_delete_crt
@anchor{gnutls_pkcs7_delete_crt}
@deftypefun {int} {gnutls_pkcs7_delete_crt} (gnutls_pkcs7_t @var{pkcs7}, int @var{indx})
@var{pkcs7}: The pkcs7 type

@var{indx}: the index of the certificate to delete

This function will delete a certificate from a PKCS7 or RFC2630
certificate set.  Index starts from 0. Returns 0 on success.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_export
@anchor{gnutls_pkcs7_export}
@deftypefun {int} {gnutls_pkcs7_export} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crt_fmt_t @var{format}, void * @var{output_data}, size_t * @var{output_data_size})
@var{pkcs7}: The pkcs7 type

@var{format}: the format of output params. One of PEM or DER.

@var{output_data}: will contain a structure PEM or DER encoded

@var{output_data_size}: holds the size of output_data (and will be
replaced by the actual size of parameters)

This function will export the pkcs7 structure to DER or PEM format.

If the buffer provided is not long enough to hold the output, then
* @code{output_data_size} is updated and @code{GNUTLS_E_SHORT_MEMORY_BUFFER} 
will be returned.

If the structure is PEM encoded, it will have a header
of "BEGIN PKCS7".

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_export2
@anchor{gnutls_pkcs7_export2}
@deftypefun {int} {gnutls_pkcs7_export2} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crt_fmt_t @var{format}, gnutls_datum_t * @var{out})
@var{pkcs7}: The pkcs7 type

@var{format}: the format of output params. One of PEM or DER.

@var{out}: will contain a structure PEM or DER encoded

This function will export the pkcs7 structure to DER or PEM format.

The output buffer is allocated using @code{gnutls_malloc()} .

If the structure is PEM encoded, it will have a header
of "BEGIN PKCS7".

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.

@strong{Since:} 3.1.3
@end deftypefun

@subheading gnutls_pkcs7_get_attr
@anchor{gnutls_pkcs7_get_attr}
@deftypefun {int} {gnutls_pkcs7_get_attr} (gnutls_pkcs7_attrs_t @var{list}, unsigned @var{idx}, char ** @var{oid}, gnutls_datum_t * @var{data}, unsigned @var{flags})
@var{list}: A list of existing attributes or @code{NULL}  for the first one

@var{idx}: the index of the attribute to get

@var{oid}: the OID of the attribute (read-only)

@var{data}: the raw data of the attribute

@var{flags}: zero or @code{GNUTLS_PKCS7_ATTR_ENCODE_OCTET_STRING} 

This function will get a PKCS @code{7}  attribute from the provided list.
The OID is a constant string, but data will be allocated and must be
deinitialized by the caller.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value. @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  is returned
if there are no data in the current index.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_get_crl_count
@anchor{gnutls_pkcs7_get_crl_count}
@deftypefun {int} {gnutls_pkcs7_get_crl_count} (gnutls_pkcs7_t @var{pkcs7})
@var{pkcs7}: The pkcs7 type

This function will return the number of certificates in the PKCS7
or RFC2630 crl set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_get_crl_raw
@anchor{gnutls_pkcs7_get_crl_raw}
@deftypefun {int} {gnutls_pkcs7_get_crl_raw} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{indx}, void * @var{crl}, size_t * @var{crl_size})
@var{pkcs7}: The pkcs7 type

@var{indx}: contains the index of the crl to extract

@var{crl}: the contents of the crl will be copied there (may be null)

@var{crl_size}: should hold the size of the crl

This function will return a crl of the PKCS7 or RFC2630 crl set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.  If the provided buffer is not long enough,
then  @code{crl_size} is updated and @code{GNUTLS_E_SHORT_MEMORY_BUFFER}  is
returned.  After the last crl has been read
@code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be returned.
@end deftypefun

@subheading gnutls_pkcs7_get_crl_raw2
@anchor{gnutls_pkcs7_get_crl_raw2}
@deftypefun {int} {gnutls_pkcs7_get_crl_raw2} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{indx}, gnutls_datum_t * @var{crl})
@var{pkcs7}: The pkcs7 type

@var{indx}: contains the index of the crl to extract

@var{crl}: will contain the contents of the CRL in an allocated buffer

This function will return a DER encoded CRL of the PKCS7 or RFC2630 crl set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.  After the last crl has been read
@code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be returned.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_get_crt_count
@anchor{gnutls_pkcs7_get_crt_count}
@deftypefun {int} {gnutls_pkcs7_get_crt_count} (gnutls_pkcs7_t @var{pkcs7})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

This function will return the number of certificates in the PKCS7
or RFC2630 certificate set.

@strong{Returns:} On success, a positive number is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_get_crt_raw
@anchor{gnutls_pkcs7_get_crt_raw}
@deftypefun {int} {gnutls_pkcs7_get_crt_raw} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{indx}, void * @var{certificate}, size_t * @var{certificate_size})
@var{pkcs7}: should contain a gnutls_pkcs7_t type

@var{indx}: contains the index of the certificate to extract

@var{certificate}: the contents of the certificate will be copied
there (may be null)

@var{certificate_size}: should hold the size of the certificate

This function will return a certificate of the PKCS7 or RFC2630
certificate set.

After the last certificate has been read
@code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be returned.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.  If the provided buffer is not long enough,
then  @code{certificate_size} is updated and
@code{GNUTLS_E_SHORT_MEMORY_BUFFER}  is returned.
@end deftypefun

@subheading gnutls_pkcs7_get_crt_raw2
@anchor{gnutls_pkcs7_get_crt_raw2}
@deftypefun {int} {gnutls_pkcs7_get_crt_raw2} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{indx}, gnutls_datum_t * @var{cert})
@var{pkcs7}: should contain a gnutls_pkcs7_t type

@var{indx}: contains the index of the certificate to extract

@var{cert}: will hold the contents of the certificate; must be deallocated with @code{gnutls_free()} 

This function will return a certificate of the PKCS7 or RFC2630
certificate set.

After the last certificate has been read
@code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be returned.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.  If the provided buffer is not long enough,
then  @code{certificate_size} is updated and
@code{GNUTLS_E_SHORT_MEMORY_BUFFER}  is returned.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_get_embedded_data
@anchor{gnutls_pkcs7_get_embedded_data}
@deftypefun {int} {gnutls_pkcs7_get_embedded_data} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{flags}, gnutls_datum_t * @var{data})
@var{pkcs7}: should contain a gnutls_pkcs7_t type

@var{flags}: must be zero or @code{GNUTLS_PKCS7_EDATA_GET_RAW} 

@var{data}: will hold the embedded data in the provided structure

This function will return the data embedded in the signature of
the PKCS7 structure. If no data are available then
@code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be returned.

The returned data must be de-allocated using @code{gnutls_free()} .

Note, that this function returns the exact same data that are
authenticated. If the @code{GNUTLS_PKCS7_EDATA_GET_RAW}  flag is provided,
the returned data will be including the wrapping tag/value as
they are encoded in the structure.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.

@strong{Since:} 3.4.8
@end deftypefun

@subheading gnutls_pkcs7_get_embedded_data_oid
@anchor{gnutls_pkcs7_get_embedded_data_oid}
@deftypefun {const char *} {gnutls_pkcs7_get_embedded_data_oid} (gnutls_pkcs7_t @var{pkcs7})
@var{pkcs7}: should contain a gnutls_pkcs7_t type

This function will return the OID of the data embedded in the signature of
the PKCS7 structure. If no data are available then @code{NULL}  will be
returned. The returned value will be valid during the lifetime
of the  @code{pkcs7} structure.

@strong{Returns:} On success, a pointer to an OID string, @code{NULL}  on error.

@strong{Since:} 3.5.5
@end deftypefun

@subheading gnutls_pkcs7_get_signature_count
@anchor{gnutls_pkcs7_get_signature_count}
@deftypefun {int} {gnutls_pkcs7_get_signature_count} (gnutls_pkcs7_t @var{pkcs7})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

This function will return the number of signatures in the PKCS7
structure.

@strong{Returns:} On success, a positive number is returned, otherwise a
negative error value.

@strong{Since:} 3.4.3
@end deftypefun

@subheading gnutls_pkcs7_get_signature_info
@anchor{gnutls_pkcs7_get_signature_info}
@deftypefun {int} {gnutls_pkcs7_get_signature_info} (gnutls_pkcs7_t @var{pkcs7}, unsigned @var{idx}, gnutls_pkcs7_signature_info_st * @var{info})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

@var{idx}: the index of the signature info to check

@var{info}: will contain the output signature

This function will return information about the signature identified
by idx in the provided PKCS @code{7}  structure. The information should be
deinitialized using @code{gnutls_pkcs7_signature_info_deinit()} .

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_import
@anchor{gnutls_pkcs7_import}
@deftypefun {int} {gnutls_pkcs7_import} (gnutls_pkcs7_t @var{pkcs7}, const gnutls_datum_t * @var{data}, gnutls_x509_crt_fmt_t @var{format})
@var{pkcs7}: The data to store the parsed PKCS7.

@var{data}: The DER or PEM encoded PKCS7.

@var{format}: One of DER or PEM

This function will convert the given DER or PEM encoded PKCS7 to
the native @code{gnutls_pkcs7_t}  format.  The output will be stored in
 @code{pkcs7} . Any signed data that may be present inside the  @code{pkcs7} structure, like certificates set by @code{gnutls_pkcs7_set_crt()} , will
be freed and overwritten by this function.

If the PKCS7 is PEM encoded it should have a header of "PKCS7".

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_init
@anchor{gnutls_pkcs7_init}
@deftypefun {int} {gnutls_pkcs7_init} (gnutls_pkcs7_t * @var{pkcs7})
@var{pkcs7}: A pointer to the type to be initialized

This function will initialize a PKCS7 structure. PKCS7 structures
usually contain lists of X.509 Certificates and X.509 Certificate
revocation lists.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_print
@anchor{gnutls_pkcs7_print}
@deftypefun {int} {gnutls_pkcs7_print} (gnutls_pkcs7_t @var{pkcs7}, gnutls_certificate_print_formats_t @var{format}, gnutls_datum_t * @var{out})
@var{pkcs7}: The PKCS7 struct to be printed

@var{format}: Indicate the format to use

@var{out}: Newly allocated datum with null terminated string.

This function will pretty print a signed PKCS @code{7}  structure, suitable for
display to a human.

Currently the supported formats are @code{GNUTLS_CRT_PRINT_FULL}  and
@code{GNUTLS_CRT_PRINT_COMPACT} .

The output  @code{out} needs to be deallocated using @code{gnutls_free()} .

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_print_signature_info
@anchor{gnutls_pkcs7_print_signature_info}
@deftypefun {int} {gnutls_pkcs7_print_signature_info} (gnutls_pkcs7_signature_info_st * @var{info}, gnutls_certificate_print_formats_t @var{format}, gnutls_datum_t * @var{out})
@var{info}: The PKCS7 signature info struct to be printed

@var{format}: Indicate the format to use

@var{out}: Newly allocated datum with null terminated string.

This function will pretty print a PKCS @code{7}  signature info structure, suitable
for display to a human.

Currently the supported formats are @code{GNUTLS_CRT_PRINT_FULL}  and
@code{GNUTLS_CRT_PRINT_COMPACT} .

The output  @code{out} needs to be deallocated using @code{gnutls_free()} .

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.

@strong{Since:} 3.6.14
@end deftypefun

@subheading gnutls_pkcs7_set_crl
@anchor{gnutls_pkcs7_set_crl}
@deftypefun {int} {gnutls_pkcs7_set_crl} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crl_t @var{crl})
@var{pkcs7}: The pkcs7 type

@var{crl}: the DER encoded crl to be added

This function will add a parsed CRL to the PKCS7 or RFC2630 crl
set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_set_crl_raw
@anchor{gnutls_pkcs7_set_crl_raw}
@deftypefun {int} {gnutls_pkcs7_set_crl_raw} (gnutls_pkcs7_t @var{pkcs7}, const gnutls_datum_t * @var{crl})
@var{pkcs7}: The pkcs7 type

@var{crl}: the DER encoded crl to be added

This function will add a crl to the PKCS7 or RFC2630 crl set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_set_crt
@anchor{gnutls_pkcs7_set_crt}
@deftypefun {int} {gnutls_pkcs7_set_crt} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crt_t @var{crt})
@var{pkcs7}: The pkcs7 type

@var{crt}: the certificate to be copied.

This function will add a parsed certificate to the PKCS7 or
RFC2630 certificate set.  This is a wrapper function over
@code{gnutls_pkcs7_set_crt_raw()}  .

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_set_crt_raw
@anchor{gnutls_pkcs7_set_crt_raw}
@deftypefun {int} {gnutls_pkcs7_set_crt_raw} (gnutls_pkcs7_t @var{pkcs7}, const gnutls_datum_t * @var{crt})
@var{pkcs7}: The pkcs7 type

@var{crt}: the DER encoded certificate to be added

This function will add a certificate to the PKCS7 or RFC2630
certificate set.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.
@end deftypefun

@subheading gnutls_pkcs7_sign
@anchor{gnutls_pkcs7_sign}
@deftypefun {int} {gnutls_pkcs7_sign} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crt_t @var{signer}, gnutls_privkey_t @var{signer_key}, const gnutls_datum_t * @var{data}, gnutls_pkcs7_attrs_t @var{signed_attrs}, gnutls_pkcs7_attrs_t @var{unsigned_attrs}, gnutls_digest_algorithm_t @var{dig}, unsigned @var{flags})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

@var{signer}: the certificate to sign the structure

@var{signer_key}: the key to sign the structure

@var{data}: The data to be signed or @code{NULL}  if the data are already embedded

@var{signed_attrs}: Any additional attributes to be included in the signed ones (or @code{NULL} )

@var{unsigned_attrs}: Any additional attributes to be included in the unsigned ones (or @code{NULL} )

@var{dig}: The digest algorithm to use for signing

@var{flags}: Should be zero or one of @code{GNUTLS_PKCS7}  flags

This function will add a signature in the provided PKCS @code{7}  structure
for the provided data. Multiple signatures can be made with different
signers.

The available flags are:
@code{GNUTLS_PKCS7_EMBED_DATA} , @code{GNUTLS_PKCS7_INCLUDE_TIME} , @code{GNUTLS_PKCS7_INCLUDE_CERT} ,
and @code{GNUTLS_PKCS7_WRITE_SPKI} . They are explained in the @code{gnutls_pkcs7_sign_flags} 
definition.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value.

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_signature_info_deinit
@anchor{gnutls_pkcs7_signature_info_deinit}
@deftypefun {void} {gnutls_pkcs7_signature_info_deinit} (gnutls_pkcs7_signature_info_st * @var{info})
@var{info}: should point to a @code{gnutls_pkcs7_signature_info_st}  structure

This function will deinitialize any allocated value in the
provided @code{gnutls_pkcs7_signature_info_st} .

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_verify
@anchor{gnutls_pkcs7_verify}
@deftypefun {int} {gnutls_pkcs7_verify} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_trust_list_t @var{tl}, gnutls_typed_vdata_st * @var{vdata}, unsigned int @var{vdata_size}, unsigned @var{idx}, const gnutls_datum_t * @var{data}, unsigned @var{flags})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

@var{tl}: A list of trusted certificates

@var{vdata}: an array of typed data

@var{vdata_size}: the number of data elements

@var{idx}: the index of the signature info to check

@var{data}: The data to be verified or @code{NULL} 

@var{flags}: Zero or an OR list of @code{gnutls_certificate_verify_flags} 

This function will verify the provided data against the signature
present in the SignedData of the PKCS @code{7}  structure. If the data
provided are NULL then the data in the encapsulatedContent field
will be used instead.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value. A verification error results to a
@code{GNUTLS_E_PK_SIG_VERIFY_FAILED}  and the lack of encapsulated data
to verify to a @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE} .

@strong{Since:} 3.4.2
@end deftypefun

@subheading gnutls_pkcs7_verify_direct
@anchor{gnutls_pkcs7_verify_direct}
@deftypefun {int} {gnutls_pkcs7_verify_direct} (gnutls_pkcs7_t @var{pkcs7}, gnutls_x509_crt_t @var{signer}, unsigned @var{idx}, const gnutls_datum_t * @var{data}, unsigned @var{flags})
@var{pkcs7}: should contain a @code{gnutls_pkcs7_t}  type

@var{signer}: the certificate believed to have signed the structure

@var{idx}: the index of the signature info to check

@var{data}: The data to be verified or @code{NULL} 

@var{flags}: Zero or an OR list of @code{gnutls_certificate_verify_flags} 

This function will verify the provided data against the signature
present in the SignedData of the PKCS @code{7}  structure. If the data
provided are NULL then the data in the encapsulatedContent field
will be used instead.

Note that, unlike @code{gnutls_pkcs7_verify()}  this function does not
verify the key purpose of the signer. It is expected for the caller
to verify the intended purpose of the @code{signer}  -e.g., via @code{gnutls_x509_crt_get_key_purpose_oid()} ,
or @code{gnutls_x509_crt_check_key_purpose()} .

Note also, that since GnuTLS 3.5.6 this function introduces checks in the
end certificate ( @code{signer} ), including time checks and key usage checks.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error value. A verification error results to a
@code{GNUTLS_E_PK_SIG_VERIFY_FAILED}  and the lack of encapsulated data
to verify to a @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE} .

@strong{Since:} 3.4.2
@end deftypefun