Tested with both OpenSSL 1.1 from base and 3.0 (from ports). Both instances fail when trying to set the kernels dump ioctl because the device I was using is md(4) based:
```
# rsa.public generated with the following 2 commands:
# - openssl genrsa -out rsa.private 2048
# - openssl rsa -in rsa.priv -out rsa.public -pubout -outform PEM
$ cat rsa.public
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAz/Kc/3eSS4uCoEBhzsI7
P3Vy7+Ar/JcKHUL6nlrKwOECOTaQf63KhIxvHh3wsBIpiqIDoN0MgumECCdhco8G
mdwcFzf5zavq7LsYPsfY79nEUgrtqNPxS0hekNhg49RVjRBFdm++CL4c1HHoj/QO
V2+SDDPO+2/0ZlfZdtbglYNTB+jh3YpgXlh0ap5axpY/s47fcJVhHGDFBChwaGPd
0Kb16XCqmHyCAx5q2W+haBDwEXhXSBSbFMCB5luItteoG/66gtUK1fpps9Jmx0e8
MHxnkFYctVAbDw/p1boyQQWQ7o9FyLyKWf8/hx6RPyA9kV3oFPYhE0Pf/YZOzRcU
WwIDAQAB
-----END PUBLIC KEY-----
$ sudo dumpon -vvv -k ./rsa.public /dev/md0
dumpon: ioctl(DIOCSKERNELDUMP): Operation not supported
$ sudo `make -V.OBJDIR`/dumpon -vvv -k ./rsa.public /dev/md0
dumpon: ioctl(DIOCSKERNELDUMP): Operation not supported
```
The above public key was