Hi Matt, Your suggestion helped a lot for the initial application tag.
I must confess I haven’t jet googled the method ANS1_item_ex yet what exactly it does and how it behave and can be used. But now I’m wondering how I can “cascade” using this method to influence the encoding to avoid the writing of the additional bytes after the OID gest encoded and before the innerToken is encoded: ….. 0x05 0x05 0x02 0x04 0x76 0xa0 0x74 ….(here are a lot of bytes omitted) Best regards Max From: openssl-users <openssl-users-boun...@openssl.org> on behalf of Matt Caswell <m...@openssl.org> Date: Thursday, 4. November 2021 at 17:14 To: openssl-users@openssl.org <openssl-users@openssl.org> Subject: Re: ASN1 <-> DER encoding with application tag On 04/11/2021 13:58, Max Larsson wrote: > i2d_GSSAPI_CONTEXTTOKEN( negToken,&p ); > You can tell i2d to encode using "application" tagging like this: ASN1_item_ex_i2d((const ASN1_VALUE **)&negToken, &p, ASN1_ITEM_rptr(GSSAPI_CONTEXTTOKEN), 0, ASN1_TFLG_APPLICATION); Matt > for( intlen = 0;len < bufferSize;len++ ) { > > if( ( len % 8) == 0) > > printf( " "); > > if( ( len % 16) == 0) > > printf( "\n\t\t"); > > printf( " 0x%02x",(short)buffer[ len ] ); > > } > > printf( "\n"); > > . . . > > The code above output the following DER encoded structure (the > difference marled in bold): > > *0**x**3**0**0**x**81 0x80*0x060x060x2b0x060x010x050x050x02*0x04 > 0x76*0xa00x74 > > The google result, which I found seems to point into the direction to > use application tags to encode. > > But I haven’t found any example or how to how to achieve this with > openssl, can anyone give me sone hints? > > Best regards > > Max Larsson > > Mit freundlichen Grüßen > Best regards > > Dipl.-Inform. Max Larsson > Geschäftsleitung > > ------------------------------------------------------------------------ > > phone: +49(0)6151/62908-75 > fax: > email: max.lars...@facilityboss.biz <mailto:max.lars...@facilityboss.biz> > web: http://facilityboss.biz <http://facilityboss.biz> > > > > *facilityboss <http://facilityboss.biz>* > Bad Nauheimer Str. 4 > 64289 Darmstadt > Germany > > Sitz der Gesellschaft: Darmstadt > Registergericht: Amtsgericht Darmstadt, HRB 86193 > Geschäftsführer: Dipl.-Inform Max Lars Robert Larsson > > ------------------------------------------------------------------------ > > Diese E-Mail enthält unter Umständen vertrauliche und/oder rechtlich > geschützte Informationen, die allein für den Adressaten bestimmt sind. > Wenn Sie nicht der zutreffende Adressat sind oder diese E-Mail > irrtümlich erhalten haben, ist jede Verwendung, Verbreitung, Kopie oder > Bezugnahme auf den Inhalt dieser E-Mail verboten. Bitte informieren Sie > uns über einen eventuellen Irrtum per Telefon, per Telefax oder E-Mail. > > This e-mail may contain confidential and/or privileged information. If > you are not the intended recipient, any disclosure, copying, > distribution or reference on the contents of this e-mail is strictly > prohibited. If you have received this e-mail in error please notify us > by e-mail, facsimile or phone call. >