SMIMEA

Calculate SMIMEA RFC8162 Record from S/MIME Certificate
Version 0.01.

Or if you think you already have SMIMEA? Enter email address here. cASe matters!
Dont have a S/MIME certificate? Here are some hints:
openssl genrsa -out smime.key 2048
openssl req -new -key smime.key -out smime.csr \
  -subj "/CN=you@example.com/emailAddress=you@example.com"
openssl x509 -sha256 -req -days 365 -in smime.csr -out smime.crt \
  -CA ca.crt -CAkey ca.key \
  -setalias "Self Signed SMIME" -addtrust emailProtection \
  -addreject clientAuth -addreject serverAuth -trustout
cat smime.crt

Then copy and paste output:
-----BEGIN CERTIFICATE-----
MIIEEzCCAfsCAQEwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCVVMxCzAJBgNV
....
shtN9l5XXWffVM2UuaxqVr4ULLm2z3PeGPNBzrlAWSvY+7kCuY3d
-----END CERTIFICATE-----
Date: 09-OCT-2024 13:16 UTC

Copyright © 2015 - 2024 DC Communications Inc.
Comments concerning the design of this site should be sent to . Permission to use, copy, modify, and/or distribute this software for non-commercial use without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
THE SERVICE AND SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SERVICE OR SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SERVICE OR SOFTWARE.