doc/crypto/X509_get0_signature.pod

   1 =pod
   2
   3 =head1 NAME
   4
   5 X509_get0_signature, X509_get_signature_nid, X509_get0_tbs_sigalg,
   6 X509_REQ_get0_signature, X509_REQ_get_signature_nid, X509_CRL_get0_signature,
   7 X509_CRL_get_signature_nid - signature information.
   8
   9 =head1 SYNOPSIS
  10
  11  #include <openssl/x509.h>
  12
  13  void X509_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
  14                           const X509 *x);
  15  int X509_get_signature_nid(const X509 *x);
  16  X509_ALGOR *X509_get0_tbs_sigalg(X509 *x);
  17
  18  void X509_REQ_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
  19                               const X509_REQ *crl);
  20  int X509_REQ_get_signature_nid(const X509_REQ *crl);
  21
  22  void X509_CRL_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
  23                               const X509_CRL *crl);
  24  int X509_CRL_get_signature_nid(const X509_CRL *crl);
  25
  26 =head1 DESCRIPTION
  27
  28 X509_get0_signature() sets B<*psig> to the signature of B<x> and B<*palg>
  29 to the signature algorithm of B<x>. The values returned are internal
  30 pointers which B<MUST NOT> be freed up after the call.
  31
  32 X509_get0_tbs_sigalg() returns the signature algorithm in the signed
  33 portion of B<x>.
  34
  35 X509_get_signature_nid() returns the NID corresponding to the signature
  36 algorithm of B<x>.
  37
  38 X509_REQ_get0_signature(), X509_REQ_get_signature_nid()
  39 X509_CRL_get0_signature() and X509_CRL_get_signature_nid() perform the
  40 same function for certificate requests and CRLs.
  41
  42 =head1 NOTES
  43
  44 These functions provide lower level access to signatures in certificates
  45 where an application wishes to analyse or generate a signature in a form
  46 where X509_sign() et al is not appropriate (for example a non standard
  47 or unsupported format).
  48
  49 =head1 RETURN VALUES
  50
  51 X509_get_signature_nid(), X509_REQ_get_signature_nid() and
  52 X509_CRL_get_signature_nid() return a NID.
  53
  54 X509_get0_signature(), X509_REQ_get0_signature() and
  55 X509_CRL_get0_signature() do not return values.
  56
  57 =head1 SEE ALSO
  58
  59 L<d2i_X509(3)>,
  60 L<ERR_get_error(3)>,
  61 L<X509_CRL_get0_by_serial(3)>,
  62 L<X509_get_ext_d2i(3)>,
  63 L<X509_get_extension_flags(3)>,
  64 L<X509_get_pubkey(3)>,
  65 L<X509_get_subject_name(3)>,
  66 L<X509_get_version(3)>,
  67 L<X509_NAME_add_entry_by_txt(3)>,
  68 L<X509_NAME_ENTRY_get_object(3)>,
  69 L<X509_NAME_get_index_by_NID(3)>,
  70 L<X509_NAME_print_ex(3)>,
  71 L<X509_new(3)>,
  72 L<X509_sign(3)>,
  73 L<X509V3_get_d2i(3)>,
  74 L<X509_verify_cert(3)>
  75
  76 =head1 HISTORY
  77
  78 X509_get0_signature() and X509_get_signature_nid() were first added to
  79 OpenSSL 1.0.2.
  80
  81 X509_REQ_get0_signature(), X509_REQ_get_signature_nid(),
  82 X509_CRL_get0_signature() and X509_CRL_get_signature_nid() were first added
  83 to OpenSSL 1.1.0.
  84
  85 =cut