BER string types use all UTF-8 encoding but X.690 says otherwise

[terefang]

lets cite ITU-T X.690-2021 aka ISO/IEC 8825-1:2021 (E):

8.23.5 For restricted character strings apart from UniversalString, UTF8String and BMPString, the octet string shall
contain the octets specified in ISO/IEC 2022 for encodings in an 8-bit environment, using the escape sequence and character
codings registered in accordance with ISO/IEC 2375.

which in java translates to US-ASCII or for more tolerance the ISO-8859-1 charset

8.23.7 For the UniversalString type, the octet string shall contain the octets specified in ISO/IEC 10646, using the 4-
octet canonical form (see 13.2 of ISO/IEC 10646). Signatures shall not be used. Control functions may be used provided they
satisfy the restrictions imposed by 8.23.9.

which in java translates to UTF-32 or rather transformed from UCS-4

8.23.8 For the BMPString type, the octet string shall contain the octets specified in ISO/IEC 10646, using the 2-octet BMP
form (see 13.1 of ISO/IEC 10646). Signatures shall not be used. Control functions may be used provided they satisfy the
restrictions imposed by 8.23.9.

which in java translates to UTF-16 or rather transformed from UCS-2