Decoding:
    SILC_ASN1_SET_OF(bufarray, numbufs)

    Macro used to decode set of specified type.  This returns
    an array of SilcBuffers and number of buffers in the array.  The
    SILC_ASN1_CHOICE macro may also be used with this macro.

    This macro must be used either with SILC_ASN1_ALLOC or SILC_ASN1_ACCUMUL
    flags.  Do not use this macro without flags.

     // Decode set of sequences.  Each returned buffer in the array
     // is a sequence.
     silc_asn1_decode(asn1, exts,
                      SILC_ASN1_OPTS(SILC_ASN1_ALLOC),
                      SILC_ASN1_SET_OF(&bufs, &count),
                        SILC_ASN1_TAG_SEQUENCE,
                      SILC_ASN1_END, SILC_ASN1_END);