Account Services on the Web

What is an OpenSSL Configuration File?

An OpenSSL configuration file specifies the values for your certificate (instead of having the openssl command prompt you to enter them). This helps to insure they are always correct and consistent.

How do I use an OpenSSL Configuration File?

Simply specify the name of the configuration file on the command line. For example, if your file was named openssl-request.cf you could do: 

openssl req -new -config openssl-request.cf -keyout myserver.key -out myserver.csr

What does an OpenSSL Configuration File Look Like?

Here is a sample configuration file you can copy and adapt for your use: 

#edit next line with YOUR fqdn
FQDN = whatever.dept.iastate.edu
#edit next line to choose among depts
DEPT = SE
# Do you want a SAN Cert (YES/NO)
SAN = NO

[ alt_names ]
# For a SAN Cert, put altername names here
DNS.1 = $FQDN
DNS.2 = altnameone.dept.iastate.edu
DNS.3 = altnametwo.dept.iastate.edu

#
# Once your departments are setup, no need to touch anything below here
#

[ req ]
req_extensions     = san_$SAN
distinguished_name = dept_$DEPT
default_bits       = 2048
encrypt_key        = no
prompt             = no

[ san_NO ]

[ san_YES ]
subjectAltName     = @alt_names

# setup: define one or more departments below
# use your official full department name (https://www.ir.iastate.edu/deptcodes)

[ dept_CPRE ]
C       = US
ST      = Iowa
L       = Ames
O       = Iowa State University of Science and Technology
OU      = COMPUTER ENGINEERING
CN      = $FQDN

[ dept_SE ]
C       = US
ST      = Iowa
L       = Ames
O       = Iowa State University of Science and Technology
OU      = SOFTWARE ENGINEERING
CN      = $FQDN