OpenSSL difference between v3_req and req_ext

Question

What is the difference between the two OpenSSL extensions v3_req and req_ext ?

Not able to obtain information about them using online search.

Configuration directives:

[ req ]
default_bits        = 2048
#req_extensions      = req_ext
req_extensions      = v3_req

Answer 1

These are simply names that refer to sections that need to be defined in the same config file. The sections are marked with [ and ]. v3_req is defined in the OpenSSL config file as:

[ v3_req ]
basicConstraints = CA:FALSE
keyUsage = nonRepudiation, digitalSignature, keyEncipherment

The commented out line is not found in the official OpenSSL config file. It was probably left there as placeholder to indicate how one would set an extension.