I use self-signed CA cert to sign other certificates. For some certs I need to specify subject alternative names. I can specify them during request generation (openssl req ...) and I see them in .csr file. Then I sign it with CA cert using
openssl x509 -req -extensions x509v3_config -days 365 -in ${name}.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out ${name}.crt
and next sections in openssl.cnf file:
[ x509 ]
x509_extensions = x509v3_config
[ x509v3_config ]
copy_extensions = copy
but I see no SAN in .crt file.
I know about solutions with openssl ca ... command but I have no valid [ca] section and I don't want to copy/paste it without deep understanding what it does. So I hope that exists another solution with openssl x509 ... command.
The copy_extensions directive is only understood by the openssl ca command. There is no way to copy extensions from a CSR to the certificate with the openssl x509 command.
Instead, you should specify the exact extensions you want as part of the openssl x509 command, using the same directives you used for openssl req.