func ParseSANGeneralNamesOtherNamesOnly()

in pkg/controller/common/certificates/x509_othername.go [154:220]
53 lines of code
14 McCabe index (conditional complexity)

func ParseSANGeneralNamesOtherNamesOnly(c *x509.Certificate) ([]GeneralName, error) {
	var generalNames []GeneralName
	for _, ext := range c.Extensions {
		//nolint:nestif
		if SubjectAlternativeNamesObjectIdentifier.Equal(ext.Id) {
			// rfc: should be wrapped in a sequence node:
			var generalNamesValue asn1.RawValue
			rest, err := asn1.Unmarshal(ext.Value, &generalNamesValue)
			if err != nil {
				return nil, err
			}
			if len(rest) != 0 {
				return nil, errors.New("trailing data after SubjectAlternativeNames")
			}

			if generalNamesValue.Class != asn1.ClassUniversal || generalNamesValue.Tag != asn1.TagSequence {
				return nil, errors.New("invalid GeneralNames class or tag")
			}

			rest = generalNamesValue.Bytes
			for len(rest) != 0 {
				var generalName asn1.RawValue
				rest, err = asn1.Unmarshal(rest, &generalName)
				if err != nil {
					return nil, err
				}

				if generalName.Class == asn1.ClassContextSpecific {
					switch generalName.Tag {
					case 0:
						// OtherName ::= SEQUENCE {
						//   type-id    OBJECT IDENTIFIER,
						//   value      [0] EXPLICIT ANY DEFINED BY type-id }

						var otherNameTypeObjectIdentifier asn1.ObjectIdentifier

						otherNameValueBytes, err := asn1.Unmarshal(generalName.Bytes, &otherNameTypeObjectIdentifier)
						if err != nil {
							return nil, err
						}

						var value asn1.RawValue
						vrest, err := asn1.Unmarshal(otherNameValueBytes, &value)
						if err != nil {
							return nil, err
						}
						if len(vrest) != 0 {
							return nil, errors.New("trailing data after OtherName value")
						}

						generalNames = append(generalNames, GeneralName{
							OtherName: OtherName{
								OID:   otherNameTypeObjectIdentifier,
								Value: value,
							},
						})
					default:
						// only used in tests
						ulog.Log.Info("Ignoring unsupported GeneralNames tag", "tag", generalName.Tag, "subject", c.Subject)
					}
				}
			}
		}
	}

	return generalNames, nil
}