Updated: 2021/Apr/14


X509_get0_signature(3)              OpenSSL             X509_get0_signature(3)



NAME
       X509_get0_signature, X509_REQ_set0_signature,
       X509_REQ_set1_signature_algo, X509_get_signature_nid,
       X509_get0_tbs_sigalg, X509_REQ_get0_signature,
       X509_REQ_get_signature_nid, X509_CRL_get0_signature,
       X509_CRL_get_signature_nid, X509_get_signature_info, X509_SIG_INFO_get,
       X509_SIG_INFO_set - signature information

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/x509.h>

        void X509_get0_signature(const ASN1_BIT_STRING **psig,
                                 const X509_ALGOR **palg,
                                 const X509 *x);
        void X509_REQ_set0_signature(X509_REQ *req, ASN1_BIT_STRING *psig);
        int X509_REQ_set1_signature_algo(X509_REQ *req, X509_ALGOR *palg);
        int X509_get_signature_nid(const X509 *x);
        const X509_ALGOR *X509_get0_tbs_sigalg(const X509 *x);

        void X509_REQ_get0_signature(const X509_REQ *crl,
                                     const ASN1_BIT_STRING **psig,
                                     const X509_ALGOR **palg);
        int X509_REQ_get_signature_nid(const X509_REQ *crl);

        void X509_CRL_get0_signature(const X509_CRL *crl,
                                     const ASN1_BIT_STRING **psig,
                                     const X509_ALGOR **palg);
        int X509_CRL_get_signature_nid(const X509_CRL *crl);

        int X509_get_signature_info(X509 *x, int *mdnid, int *pknid, int *secbits,
                                    uint32_t *flags);

        int X509_SIG_INFO_get(const X509_SIG_INFO *siginf, int *mdnid, int *pknid,
                             int *secbits, uint32_t *flags);
        void X509_SIG_INFO_set(X509_SIG_INFO *siginf, int mdnid, int pknid,
                               int secbits, uint32_t flags);

DESCRIPTION
       X509_get0_signature() sets *psig to the signature of x and *palg to the
       signature algorithm of x. The values returned are internal pointers
       which MUST NOT be freed up after the call.

       X509_set0_signature() and X509_REQ_set1_signature_algo() are the
       equivalent setters for the two values of X509_get0_signature().

       X509_get0_tbs_sigalg() returns the signature algorithm in the signed
       portion of x.

       X509_get_signature_nid() returns the NID corresponding to the signature
       algorithm of x.

       X509_REQ_get0_signature(), X509_REQ_get_signature_nid()
       X509_CRL_get0_signature() and X509_CRL_get_signature_nid() perform the
       same function for certificate requests and CRLs.

       X509_get_signature_info() retrieves information about the signature of
       certificate x. The NID of the signing digest is written to *mdnid, the
       public key algorithm to *pknid, the effective security bits to *secbits
       and flag details to *flags. Any of the parameters can be set to NULL if
       the information is not required.

       X509_SIG_INFO_get() and X509_SIG_INFO_set() get and set information
       about a signature in an X509_SIG_INFO structure. They are only used by
       implementations of algorithms which need to set custom signature
       information: most applications will never need to call them.

NOTES
       These functions provide lower level access to signatures in
       certificates where an application wishes to analyse or generate a
       signature in a form where X509_sign() et al is not appropriate (for
       example a non standard or unsupported format).

       The security bits returned by X509_get_signature_info() refers to
       information available from the certificate signature (such as the
       signing digest). In some cases the actual security of the signature is
       less because the signing key is less secure: for example a certificate
       signed using SHA-512 and a 1024 bit RSA key.

RETURN VALUES
       X509_get_signature_nid(), X509_REQ_get_signature_nid() and
       X509_CRL_get_signature_nid() return a NID.

       X509_get0_signature(), X509_REQ_get0_signature() and
       X509_CRL_get0_signature() do not return values.

       X509_get_signature_info() returns 1 if the signature information
       returned is valid or 0 if the information is not available (e.g.
       unknown algorithms or malformed parameters).

       X509_REQ_set1_signature_algo() returns 0 on success; or 1 on an error
       (e.g. null ALGO pointer). X509_REQ_set0_signature does not return an
       error value.

SEE ALSO
       d2i_X509(3), ERR_get_error(3), X509_CRL_get0_by_serial(3),
       X509_get_ext_d2i(3), X509_get_extension_flags(3), X509_get_pubkey(3),
       X509_get_subject_name(3), X509_get_version(3),
       X509_NAME_add_entry_by_txt(3), X509_NAME_ENTRY_get_object(3),
       X509_NAME_get_index_by_NID(3), X509_NAME_print_ex(3), X509_new(3),
       X509_sign(3), X509V3_get_d2i(3), X509_verify_cert(3)

HISTORY
       The X509_get0_signature() and X509_get_signature_nid() functions were
       added in OpenSSL 1.0.2.

       The X509_REQ_get0_signature(), X509_REQ_get_signature_nid(),
       X509_CRL_get0_signature() and X509_CRL_get_signature_nid() were added
       in OpenSSL 1.1.0.

       The X509_REQ_set0_signature() and X509_REQ_set1_signature_algo() were
       added in OpenSSL 1.1.1e.

COPYRIGHT
       Copyright 2015-2020 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



1.1.1i                            2020-12-10            X509_get0_signature(3)