# class OpenSSL::ASN1::Primitive

The parent class for all primitive encodings. Attributes are the same as for `ASN1Data`, with the addition of tagging. `Primitive` values can never be encoded with indefinite length form, thus it is not possible to set the indefinite_length attribute for `Primitive` and its sub-classes.

## `Primitive` sub-classes and their mapping to Ruby classes¶ ↑

- OpenSSL::ASN1::EndOfContent <=> value is always `nil`

- OpenSSL::ASN1::Boolean <=> value is `true` or `false`

- OpenSSL::ASN1::Integer <=> value is an `OpenSSL::BN`

- OpenSSL::ASN1::BitString <=> value is a `String`

- OpenSSL::ASN1::OctetString <=> value is a `String`

- OpenSSL::ASN1::Null <=> value is always `nil`

- OpenSSL::ASN1::Object <=> value is a `String`

- OpenSSL::ASN1::Enumerated <=> value is an `OpenSSL::BN`

- OpenSSL::ASN1::UTF8String <=> value is a `String`

- OpenSSL::ASN1::NumericString <=> value is a `String`

- OpenSSL::ASN1::PrintableString <=> value is a `String`

- OpenSSL::ASN1::T61String <=> value is a `String`

- OpenSSL::ASN1::VideotexString <=> value is a `String`

- OpenSSL::ASN1::IA5String <=> value is a `String`

- OpenSSL::ASN1::UTCTime <=> value is a `Time`

- OpenSSL::ASN1::GeneralizedTime <=> value is a `Time`

- OpenSSL::ASN1::GraphicString <=> value is a `String`

- OpenSSL::ASN1::ISO64String <=> value is a `String`

- OpenSSL::ASN1::GeneralString <=> value is a `String`

- OpenSSL::ASN1::UniversalString <=> value is a `String`

- OpenSSL::ASN1::BMPString <=> value is a `String`

## OpenSSL::ASN1::BitString¶ ↑

### Additional attributes¶ ↑

unused_bits: if the underlying BIT STRING's length is a multiple of 8 then unused_bits is 0. Otherwise unused_bits indicates the number of bits that are to be ignored in the final octet of the BitString's value.

## `OpenSSL::ASN1::ObjectId`¶ ↑

NOTE: While `OpenSSL::ASN1::ObjectId.new` will allocate a new `ObjectId`, it is not typically allocated this way, but rather that are received from parsed `ASN1` encodings.

### Additional attributes¶ ↑

- sn: the short name as defined in <openssl/objects.h>.

- ln: the long name as defined in <openssl/objects.h>.

- oid: the object identifier as a `String`, e.g. “1.2.3.4.5”

- short_name: alias for sn.

- long_name: alias for ln.

## Examples¶ ↑

With the `Exception` of OpenSSL::ASN1::EndOfContent, each `Primitive` class constructor takes at least one parameter, the value.

### Creating EndOfContent¶ ↑

    eoc = OpenSSL::ASN1::EndOfContent.new

### Creating any other `Primitive`¶ ↑

    prim = <class>.new(value) # <class> being one of the sub-classes except EndOfContent
    prim_zero_tagged_implicit = <class>.new(value, 0, :IMPLICIT)
    prim_zero_tagged_explicit = <class>.new(value, 0, :EXPLICIT)

### Attributes

tagging[RW]

May be used as a hint for encoding a value either implicitly or explicitly by setting it either to `:IMPLICIT` or to `:EXPLICIT`. tagging is not set when a ASN.1 structure is parsed using `OpenSSL::ASN1.decode`.

### Public Class Methods

OpenSSL::ASN1::Primitive.new(value [, tag, tagging, tag_class ]) → Primitive click to toggle source

value: is mandatory.

tag: optional, may be specified for tagged values. If no tag is specified, the UNIVERSAL tag corresponding to the `Primitive` sub-class is used by default.

tagging: may be used as an encoding hint to encode a value either explicitly or implicitly, see `ASN1` for possible values.

tag_class: if tag and tagging are `nil` then this is set to `:UNIVERSAL` by default. If either tag or tagging are set then `:CONTEXT_SPECIFIC` is used as the default. For possible values please cf. `ASN1`.

## Example¶ ↑

    int = OpenSSL::ASN1::Integer.new(42)
    zero_tagged_int = OpenSSL::ASN1::Integer.new(42, 0, :IMPLICIT)
    private_explicit_zero_tagged_int = OpenSSL::ASN1::Integer.new(42, 0, :EXPLICIT, :PRIVATE)

    static VALUE
    ossl_asn1_initialize(int argc, VALUE *argv, VALUE self)
    {
        VALUE value, tag, tagging, tag_class;
        int default_tag;

        rb_scan_args(argc, argv, "13", &value, &tag, &tagging, &tag_class);
        default_tag = ossl_asn1_default_tag(self);

        if (default_tag == -1 || argc > 1) {
            if(NIL_P(tag))
                ossl_raise(eASN1Error, "must specify tag number");
            if(!NIL_P(tagging) && !SYMBOL_P(tagging))
                ossl_raise(eASN1Error, "invalid tagging method");
            if(NIL_P(tag_class)) {
                if (NIL_P(tagging))
                    tag_class = sym_UNIVERSAL;
                else
                    tag_class = sym_CONTEXT_SPECIFIC;
            }
            if(!SYMBOL_P(tag_class))
                ossl_raise(eASN1Error, "invalid tag class");
        }
        else{
            tag = INT2NUM(default_tag);
            tagging = Qnil;
            tag_class = sym_UNIVERSAL;
        }
        ossl_asn1_set_tag(self, tag);
        ossl_asn1_set_value(self, value);
        ossl_asn1_set_tagging(self, tagging);
        ossl_asn1_set_tag_class(self, tag_class);
        ossl_asn1_set_indefinite_length(self, Qfalse);
        if (default_tag == V_ASN1_BIT_STRING)
            rb_ivar_set(self, sivUNUSED_BITS, INT2FIX(0));

        return self;
    }

### Public Instance Methods

to_der → DER-encoded String click to toggle source

See `ASN1Data#to_der` for details.

    static VALUE
    ossl_asn1prim_to_der(VALUE self)
    {
        ASN1_TYPE *asn1;
        long alllen, bodylen;
        unsigned char *p0, *p1;
        int j, tag, tc, state;
        VALUE str;

        if (ossl_asn1_default_tag(self) == -1) {
            str = ossl_asn1_get_value(self);
            return to_der_internal(self, 0, 0, StringValue(str));
        }

        asn1 = ossl_asn1_get_asn1type(self);
        alllen = i2d_ASN1_TYPE(asn1, NULL);
        if (alllen < 0) {
            ASN1_TYPE_free(asn1);
            ossl_raise(eASN1Error, "i2d_ASN1_TYPE");
        }
        str = ossl_str_new(NULL, alllen, &state);
        if (state) {
            ASN1_TYPE_free(asn1);
            rb_jump_tag(state);
        }
        p0 = p1 = (unsigned char *)RSTRING_PTR(str);
        i2d_ASN1_TYPE(asn1, &p0);
        ASN1_TYPE_free(asn1);
        assert(p0 - p1 == alllen);

        /* Strip header since to_der_internal() wants only the payload */
        j = ASN1_get_object((const unsigned char **)&p1, &bodylen, &tag, &tc, alllen);
        if (j & 0x80)
            ossl_raise(eASN1Error, "ASN1_get_object"); /* should not happen */

        return to_der_internal(self, 0, 0, rb_str_drop_bytes(str, alllen - bodylen));
    }