How to set the Keyusage value to new openssl X509 certificate in c program? -

unable set keyusage ( key encipherment, digital signature, crl_sign, non_repudiation e.t.c ) new x509 certificate in openssl.

help me how solve this...?

by adding below functionality can key usages, basic constraints our created certificate....  int add_ext ( x509 *cert, int nid, char *value );   // local variable definition int nid = 0;  // add algorithms internal table  openssl_add_all_algorithms( );  openssl_add_all_ciphers ( );  openssl_add_all_digests ( );   // ca certificate must include basicconstraints value // ca field set true.  add_ext ( xcert, nid_basic_constraints, "critical,ca:true" );  // key usage multi valued extension consisting of list of names // of permitted key usages.  add_ext ( xcert, nid_key_usage, "digitalsignature, nonrepudiation" );  // extensions consists of list of usages indicating purposes // certificate public key can used for..  add_ext ( xcert, nid_ext_key_usage, "critical,codesigning,1.2.3.4" );  // adds new object internal table. oid numerical form // of object, sn short name , ln long name.  nid = obj_create ( "1.2.3.4", "samp_oid", "test_oid" ); x509v3_ext_add_alias ( nid, nid_netscape_comment );  add_ext ( xcert, nid, "mq comment section" );   user defined function ---------------------  // add extension using v3 code: can set config file null because // wont reference other sections.  int add_ext ( x509 *cert, int nid, char *value ) {     //     // local variable definitions     //     x509_extension *ex = null;       x509v3_ctx ctx;       // setting context of extension      x509v3_set_ctx_nodb ( &ctx );       // issuer , subject certs: both target since self signed, no     // request , no crl      x509v3_set_ctx( &ctx, cert, cert, null, null, null );       ex = x509v3_ext_conf_nid (null, &ctx, nid, value );       if( !ex )     {         printf( "terror: in x509v3_ext_conf_nidn" );         hresult= getlasterror( );     }          return 0;      }