Internet DRAFT - draft-moskowitz-ecdsa-pki
draft-moskowitz-ecdsa-pki
wg TBD R. Moskowitz
Internet-Draft HTT Consulting
Intended status: Informational H. Birkholz
Expires: August 4, 2021 Fraunhofer SIT
L. Xia
Huawei
M. Richardson
Sandelman
January 31, 2021
Guide for building an ECC pki
draft-moskowitz-ecdsa-pki-10
Abstract
This memo provides a guide for building a PKI (Public Key
Infrastructure) using openSSL. All certificates in this guide are
ECDSA, P-256, with SHA256 certificates. Along with common End Entity
certificates, this guide provides instructions for creating IEEE
802.1AR iDevID Secure Device certificates.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 4, 2021.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 3
2.1. Requirements Terminology . . . . . . . . . . . . . . . . 3
2.2. Notations . . . . . . . . . . . . . . . . . . . . . . . . 3
2.3. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
3. The Basic PKI feature set . . . . . . . . . . . . . . . . . . 4
4. Getting started and the Root level . . . . . . . . . . . . . 4
4.1. Setting up the Environment . . . . . . . . . . . . . . . 5
4.2. Create the Root Certificate . . . . . . . . . . . . . . . 6
5. The Intermediate level . . . . . . . . . . . . . . . . . . . 7
5.1. Setting up the Intermediate Certificate Environment . . . 7
5.2. Create the Intermediate Certificate . . . . . . . . . . . 8
5.3. Create a Server EE Certificate . . . . . . . . . . . . . 10
5.4. Create a Client EE Certificate . . . . . . . . . . . . . 10
6. The 802.1AR Intermediate level . . . . . . . . . . . . . . . 11
6.1. Setting up the 802.1AR Intermediate Certificate
Environment . . . . . . . . . . . . . . . . . . . . . . . 11
6.2. Create the 802.1AR Intermediate Certificate . . . . . . . 12
6.3. Create an 802.1AR iDevID Certificate . . . . . . . . . . 14
7. Setting up a CRL for an Intermediate CA . . . . . . . . . . . 15
7.1. Create (or recreate) the CRL . . . . . . . . . . . . . . 15
7.2. Revoke a Certificate . . . . . . . . . . . . . . . . . . 15
8. Setting up OCSP for an Intermediate CA . . . . . . . . . . . 16
8.1. Create the OCSP Certificate . . . . . . . . . . . . . . . 16
8.2. Revoke a Certificate . . . . . . . . . . . . . . . . . . 18
8.3. Testing OCSP with Openssl . . . . . . . . . . . . . . . . 18
9. Footnotes . . . . . . . . . . . . . . . . . . . . . . . . . . 19
9.1. Certificate Serial Number . . . . . . . . . . . . . . . . 19
9.2. Some OpenSSL config file limitations . . . . . . . . . . 20
9.3. subjectAltName support, or lack thereof . . . . . . . . . 20
9.4. Certificates with only subjectAltName . . . . . . . . . . 20
9.5. DER support, or lack thereof . . . . . . . . . . . . . . 21
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21
11. Security Considerations . . . . . . . . . . . . . . . . . . . 21
11.1. Adequate Randomness . . . . . . . . . . . . . . . . . . 21
11.2. Key pair Theft . . . . . . . . . . . . . . . . . . . . . 22
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 22
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
13.1. Normative References . . . . . . . . . . . . . . . . . . 23
13.2. Informative References . . . . . . . . . . . . . . . . . 23
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Appendix A. OpenSSL config files . . . . . . . . . . . . . . . . 23
A.1. OpenSSL Root config file . . . . . . . . . . . . . . . . 23
A.2. OpenSSL Intermediate config file . . . . . . . . . . . . 26
A.3. OpenSSL 802.1AR Intermediate config file . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction
The IETF has a plethora of security solutions targeted at IoT. Yet
all too many IoT products are deployed with no or improperly
configured security. In particular resource constrained IoT devices
and non-IP IoT networks have not been well served in the IETF.
Additionally, more IETF (e.g. DOTS, NETCONF) efforts are requiring
secure identities, but are vague on the nature of these identities
other than to recommend use of X.509 digital certificates and perhaps
TLS.
This effort provides the steps, using the openSSL application, to
create such a PKI of ECDSA certificates. The goal is that any
developer or tester can follow these steps, create the basic objects
needed and establish the validity of the standard/program design.
This guide can even be used to create a production PKi, though
additional steps need to be taken. This could be very useful to a
small vendor needing to include 802.1AR [IEEE.802.1AR_2009] iDevIDs
in their product.
This guide was tested with openSSL 1.1.0f on Fedora 26 and creates
PEM-based certificates. DER based certificates fails (see
Section 9.5).
2. Terms and Definitions
2.1. Requirements Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
2.2. Notations
This section will contain notations
2.3. Definitions
There are no draft specific definitions at this time
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3. The Basic PKI feature set
A basic pki has two levels of hierarchy: Root and Intermediate. The
Root level has the greatest risk, and is the least used. It only
signs the Intermediate level signing certificate. As such, once the
Root level is created and signs the Intermediate level certificate it
can be locked up. In fact, the Root level could exist completely on
a mSD boot card for an ARM small computer like a RaspberryPi. A copy
of this card can be made and securely stored in a different location.
The Root level contains the Root certificate private key, a database
of all signed certificates, and the public certificate. It can also
contain the Intermediate level public certificate and a Root level
CRL.
The Intermediate level contains the Intermediate certificate private
key, the public certificate, a database of all signed certificates,
the certificate trust chain, and Intermediate level CRL. It can also
contain the End Entity public certificates. The private key file
needs to be keep securely. For example as with the Root level, a mSD
image for an ARM computer could contain the complete Intermediate
level. This image is kept offline. The End Entity CSR is copied to
it, signed, and then the signed certificate and updated database are
moved to the public image that lacks the private key.
For a simple test pki, all files can be kept on a single system that
is managed by the tester.
End Entities create a key pair and a Certificate Signing Request
(CSR). The private key is stored securely. The CSR is delivered to
the Intermediate level which uses the CSR to create the End Entity
certificate. This certificate, along with the trust chain back to
the root, is then returned to the End Entity.
There is more to a pki, but this suffices for most development and
testing needs.
4. Getting started and the Root level
This guide was developed on a Fedora 26 armv7hl system (Cubieboard2
SoC). It should work on most Linux and similar systems. All work
was done in a terminal window with extensive "cutting and pasting"
from a draft guide into the terminal window. Users of this guide may
find different behaviors based on their system.
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4.1. Setting up the Environment
The first step is to create the pki environment. Modify the
variables to suit your needs.
<sourcecode> file "setup1.sh"
# edit directory here, or override
export cadir=${cadir-/root/ca}
export rootca=${cadir}/root
export cfgdir=${cfgdir-$cadir}
export intdir=${cadir}/intermediate
export int1ardir=${cadir}/inter_1ar
export format=pem
export default_crl_days=65
mkdir -p $cadir/certs
mkdir -p $rootca
(cd $rootca
mkdir -p certs crl csr newcerts private
chmod 700 private
touch index.txt index.txt.attr
if [ ! -f serial ]; then echo 00 >serial; fi
)
sn=8
# edit these to suit
countryName="/C=US"
stateOrProvinceName="/ST=MI"
localityName="/L=Oak Park"
organizationName="/O=HTT Consulting"
#organizationalUnitName="/OU="
organizationalUnitName=
commonName="/CN=Root CA"
DN=$countryName$stateOrProvinceName$localityName
DN=$DN$organizationName$organizationalUnitName$commonName
echo $DN
export subjectAltName=email:postmaster@htt-consult.com
export default_crl_days=2048
</sourcecode>
Where:
dir
Directory for certificate files
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cadir
Directory for Root certificate files
Format
File encoding: PEM or DER
At this time only PEM works
sn
Serial Number length in bytes
For a public CA the range is 8 to 19
The Serial Number length for a public pki ranges from 8 to 19 bytes.
The use of 19 rather than 20 is to accommodate the hex representation
of the Serial Number. If it has a one in the high order bit, DER
encoding rules will place a 0x00 in front.
The DN and SAN fields are examples. Change them to appropriate
values. If you leave one blank, it will be left out of the
Certificate. "OU" above is an example of an empty DN object.
Create the file, $dir/openssl-root.cnf from the contents in
Appendix A.1.
4.2. Create the Root Certificate
Next are the openssl commands to create the Root certificate keypair,
and the Root certificate. Included are commands to view the file
contents.
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<sourcecode> file "rootcert.sh"
# Create passworded keypair file
if [ ! -f $rootca/private/ca.key.$format ]; then
echo GENERATING KEY
openssl genpkey $pass -aes256 -algorithm ec\
-pkeyopt ec_paramgen_curve:prime256v1\
-outform $format -pkeyopt ec_param_enc:named_curve\
-out $rootca/private/ca.key.$format
chmod 400 $rootca/private/ca.key.$format
openssl pkey $passin -inform $format -in $rootca/private/ca.key.$format\
-text -noout
fi
# Create Self-signed Root Certificate file
# 7300 days = 20 years; Intermediate CA is 10 years.
echo GENERATING and SIGNING REQ
openssl req -config $cfgdir/openssl-root.cnf $passin \
-set_serial 0x$(openssl rand -hex $sn)\
-keyform $format -outform $format\
-key $rootca/private/ca.key.$format -subj "$DN"\
-new -x509 -days 7300 -sha256 -extensions v3_ca\
-out $cadir/certs/ca.cert.$format
#
openssl x509 -inform $format -in $cadir/certs/ca.cert.$format\
-text -noout
openssl x509 -purpose -inform $format\
-in $cadir/certs/ca.cert.$format -inform $format
</sourcecode>
5. The Intermediate level
5.1. Setting up the Intermediate Certificate Environment
The next part is to create the Intermediate pki environment. Modify
the variables to suit your needs. In particular, set the variables
for CRL and/or OCSP support.
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<sourcecode> file "intermediate_setup.sh"
export intdir=${intdir-$cadir/intermediate}
mkdir -p $intdir
(
cd $intdir
mkdir -p certs crl csr newcerts private
chmod 700 private
touch index.txt index.txt.attr
if [ ! -f serial ]; then echo 00 >serial; fi
)
sn=8 # hex 8 is minimum, 19 is maximum
echo 1000 > $intdir/crlnumber
# cd $dir
export crlDP=
# For CRL support use uncomment these:
#crl=intermediate.crl.pem
#crlurl=www.htt-consult.com/pki/$crl
#export crlDP="URI:http://$crlurl"
export default_crl_days=30
export ocspIAI=
# For OCSP support use uncomment these:
#ocspurl=ocsp.htt-consult.com
#export ocspIAI="OCSP;URI:http://$ocspurl"
commonName="/CN=Signing CA"
DN=$countryName$stateOrProvinceName$localityName$organizationName
DN=$DN$organizationalUnitName$commonName
echo $DN
</sourcecode>
Create the file, $dir/openssl-intermediate.cnf from the contents in
Appendix A.2. Uncomment lines for crlDistributionPoints and
authorityInfoAccess if using CRLs or OSCP repectfully.
5.2. Create the Intermediate Certificate
Here are the openssl commands to create the Intermediate certificate
keypair, Intermediate certificate signed request (CSR), and the
Intermediate certificate. Included are commands to view the file
contents.
<sourcecode> file "intermediate_cert.sh"
# Create passworded keypair file
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if [ ! -f $intdir/private/intermediate.key.$format ]; then
echo GENERATING intermediate KEY
openssl genpkey $pass -aes256 -algorithm ec \
-pkeyopt ec_paramgen_curve:prime256v1 \
-outform $format -pkeyopt ec_param_enc:named_curve\
-out $intdir/private/intermediate.key.$format
chmod 400 $intdir/private/intermediate.key.$format
openssl pkey $passin -inform $format\
-in $intdir/private/intermediate.key.$format -text -noout
fi
# Create the CSR
echo GENERATING and SIGNING REQ intermediate
openssl req -config $cfgdir/openssl-root.cnf $passin \
-key $intdir/private/intermediate.key.$format -batch \
-keyform $format -outform $format -subj "$DN" -new -sha256\
-out $intdir/csr/intermediate.csr.$format
openssl req -text -noout -verify -inform $format\
-in $intdir/csr/intermediate.csr.$format
# Create Intermediate Certificate file
openssl rand -hex $sn > $intdir/serial # hex 8 is minimum, 19 is maximum
if [ ! -f $cadir/certs/intermediate.cert.pem ]; then
# Note 'openssl ca' does not support DER format
openssl ca -config $cfgdir/openssl-root.cnf -days 3650 $passin \
-extensions v3_intermediate_ca -notext -md sha256 -batch \
-in $intdir/csr/intermediate.csr.$format\
-out $cadir/certs/intermediate.cert.pem
chmod 444 $cadir/certs/intermediate.cert.$format
rm -f $cadir/certs/ca-chain.cert.$format
fi
openssl verify -CAfile $cadir/certs/ca.cert.$format\
$cadir/certs/intermediate.cert.$format
openssl x509 -noout -text -in $cadir/certs/intermediate.cert.$format
# Create the certificate chain file
if [ ! -f $cadir/certs/ca-chain.cert.$format ]; then
cat $cadir/certs/intermediate.cert.$format\
$cadir/certs/ca.cert.$format > $cadir/certs/ca-chain.cert.$format
chmod 444 $cadir/certs/ca-chain.cert.$format
fi
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</sourcecode>
5.3. Create a Server EE Certificate
Here are the openssl commands to create a Server End Entity
certificate keypair, Server certificate signed request (CSR), and the
Server certificate. Included are commands to view the file contents.
<sourcecode> file "end-server.sh"
commonName=
DN=$countryName$stateOrProvinceName$localityName
DN=$DN$organizationName$organizationalUnitName$commonName
echo $DN
serverfqdn=www.example.com
emailaddr=postmaster@htt-consult.com
export subjectAltName="DNS:$serverfqdn, email:$emailaddr"
echo $subjectAltName
openssl genpkey -algorithm ec -pkeyopt ec_paramgen_curve:prime256v1\
-pkeyopt ec_param_enc:named_curve\
-out $dir/private/$serverfqdn.key.$format
chmod 400 $dir/private/$serverfqdn.$format
openssl pkey -in $dir/private/$serverfqdn.key.$format -text -noout
openssl req -config $dir/openssl-intermediate.cnf\
-key $dir/private/$serverfqdn.key.$format \
-subj "$DN" -new -sha256 -out $dir/csr/$serverfqdn.csr.$format
openssl req -text -noout -verify -in $dir/csr/$serverfqdn.csr.$format
openssl rand -hex $sn > $dir/serial # hex 8 is minimum, 19 is maximum
# Note 'openssl ca' does not support DER format
openssl ca -config $dir/openssl-intermediate.cnf -days 375\
-extensions server_cert -notext -md sha256 \
-in $dir/csr/$serverfqdn.csr.$format\
-out $dir/certs/$serverfqdn.cert.$format
chmod 444 $dir/certs/$serverfqdn.cert.$format
openssl verify -CAfile $dir/certs/ca-chain.cert.$format\
$dir/certs/$serverfqdn.cert.$format
openssl x509 -noout -text -in $dir/certs/$serverfqdn.cert.$format
</sourcecode>
5.4. Create a Client EE Certificate
Here are the openssl commands to create a Client End Entity
certificate keypair, Client certificate signed request (CSR), and the
Client certificate. Included are commands to view the file contents.
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<sourcecode> file "end-client-dn.sh"
commonName=
UserID="/UID=rgm"
DN=$countryName$stateOrProvinceName$localityName
DN=$DN$organizationName$organizationalUnitName$commonName$UserID
echo $DN
clientemail=rgm@example.com
</sourcecode>
<sourcecode> file "end-client.sh"
export subjectAltName="email:$clientemail"
echo $subjectAltName
if [ ! -f $intdir/private/$clientemail.key.$format ]; then
openssl genpkey $pass -algorithm ec -pkeyopt ec_paramgen_curve:prime256v1\
-pkeyopt ec_param_enc:named_curve\
-out $intdir/private/$clientemail.key.$format
chmod 400 $intdir/private/$clientemail.key.$format
openssl pkey $passin -in $intdir/private/$clientemail.key.$format -text -noout
fi
openssl req -config $cfgdir/openssl-intermediate.cnf $passin \
-key $intdir/private/$clientemail.key.$format \
-subj "$DN" -new -sha256 -out $intdir/csr/$clientemail.csr.$format
openssl req -text -noout -verify\
-in $intdir/csr/$clientemail.csr.$format
openssl rand -hex $sn > $intdir/serial # hex 8 is minimum, 19 is maximum
# Note 'openssl ca' does not support DER format
openssl ca -config $cfgdir/openssl-intermediate.cnf -days 375\
-extensions usr_cert -notext -md sha256 $passin \
-in $intdir/csr/$clientemail.csr.$format -batch\
-out $cadir/certs/$clientemail.cert.$format
chmod 444 $cadir/certs/$clientemail.cert.$format
openssl verify -CAfile $cadir/certs/ca-chain.cert.$format\
$cadir/certs/$clientemail.cert.$format
openssl x509 -noout -text -in $cadir/certs/$clientemail.cert.$format
</sourcecode>
6. The 802.1AR Intermediate level
6.1. Setting up the 802.1AR Intermediate Certificate Environment
The next part is to create the 802.1AR Intermediate pki environment.
This is very similar to the Intermediate pki environment. Modify the
variables to suit your needs.
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<sourcecode> file "intermediate_1ar_setup.sh"
export dir=$cadir/8021ARintermediate
mkdir $dir
cd $dir
mkdir certs crl csr newcerts private
chmod 700 private
touch index.txt
sn=8 # hex 8 is minimum, 19 is maximum
echo 1000 > $dir/crlnumber
# cd $dir
export crlDP=
# For CRL support use uncomment these:
#crl=8021ARintermediate.crl.pem
#crlurl=www.htt-consult.com/pki/$crl
#export crlDP="URI:http://$crlurl"
export default_crl_days=30
export ocspIAI=
# For OCSP support use uncomment these:
#ocspurl=ocsp.htt-consult.com
#export ocspIAI="OCSP;URI:http://$ocspurl"
countryName="/C=US"
stateOrProvinceName="/ST=MI"
localityName="/L=Oak Park"
organizationName="/O=HTT Consulting"
organizationalUnitName="/OU=Devices"
#organizationalUnitName=
commonName="/CN=802.1AR CA"
DN=$countryName$stateOrProvinceName$localityName$organizationName
DN=$DN$organizationalUnitName$commonName
echo $DN
export subjectAltName=email:postmaster@htt-consult.com
echo $subjectAltName
</sourcecode>
Create the file, $dir/openssl-8021ARintermediate.cnf from the
contents in Appendix A.3. Uncomment lines for crlDistributionPoints
and authorityInfoAccess if using CRLs or OSCP repectfully.
6.2. Create the 802.1AR Intermediate Certificate
Here are the openssl commands to create the 802.1AR Intermediate
certificate keypair, 802.1AR Intermediate certificate signed request
(CSR), and the 802.1AR Intermediate certificate. Included are
commands to view the file contents.
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<sourcecode> file "intermediate_1ar_cert.sh"
# Create passworded keypair file
openssl genpkey -aes256 -algorithm ec\
-pkeyopt ec_paramgen_curve:prime256v1 \
-outform $format -pkeyopt ec_param_enc:named_curve\
-out $dir/private/8021ARintermediate.key.$format
chmod 400 $dir/private/8021ARintermediate.key.$format
openssl pkey -inform $format\
-in $dir/private/8021ARintermediate.key.$format -text -noout
# Create the CSR
openssl req -config $cadir/openssl-root.cnf\
-key $dir/private/8021ARintermediate.key.$format \
-keyform $format -outform $format -subj "$DN" -new -sha256\
-out $dir/csr/8021ARintermediate.csr.$format
openssl req -text -noout -verify -inform $format\
-in $dir/csr/8021ARintermediate.csr.$format
# Create 802.1AR Intermediate Certificate file
# The following does NOT work for DER
openssl rand -hex $sn > $dir/serial # hex 8 is minimum, 19 is maximum
# Note 'openssl ca' does not support DER format
openssl ca -config $cadir/openssl-root.cnf -days 3650\
-extensions v3_intermediate_ca -notext -md sha256\
-in $dir/csr/8021ARintermediate.csr.$format\
-out $dir/certs/8021ARintermediate.cert.pem
chmod 444 $dir/certs/8021ARintermediate.cert.$format
openssl verify -CAfile $cadir/certs/ca.cert.$format\
$dir/certs/8021ARintermediate.cert.$format
openssl x509 -noout -text\
-in $dir/certs/8021ARintermediate.cert.$format
# Create the certificate chain file
cat $dir/certs/8021ARintermediate.cert.$format\
$cadir/certs/ca.cert.$format > $dir/certs/ca-chain.cert.$format
chmod 444 $dir/certs/ca-chain.cert.$format
</sourcecode>
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6.3. Create an 802.1AR iDevID Certificate
Here are the openssl commands to create a 802.1AR iDevID certificate
keypair, iDevID certificate signed request (CSR), and the iDevID
certificate. Included are commands to view the file contents.
<sourcecode> file "idevid-csr-cert.sh"
DevID=Wt1234
countryName=
stateOrProvinceName=
localityName=
organizationName="/O=HTT Consulting"
organizationalUnitName="/OU=Devices"
commonName=
serialNumber="/serialNumber=$DevID"
DN=$countryName$stateOrProvinceName$localityName
DN=$DN$organizationName$organizationalUnitName$commonName
DN=$DN$serialNumber
echo $DN
# hwType is OID for HTT Consulting, devices, sensor widgets
export hwType=1.3.6.1.4.1.6715.10.1
export hwSerialNum=01020304 # Some hex
export subjectAltName="otherName:1.3.6.1.5.5.7.8.4;SEQ:hmodname"
echo $hwType - $hwSerialNum
if [ ! -f $dir/private/$DevID.key.$format ]; then
openssl genpkey -algorithm ec -pkeyopt ec_paramgen_curve:prime256v1\
-pkeyopt ec_param_enc:named_curve\
-out $dir/private/$DevID.key.$format
chmod 400 $dir/private/$DevID.key.$format
fi
openssl pkey -in $dir/private/$DevID.key.$format -text -noout
openssl req -config $cfgdir/openssl-8021ARintermediate.cnf\
-key $dir/private/$DevID.key.$format \
-subj "$DN" -new -sha256 -out $dir/csr/$DevID.csr.$format
openssl req -text -noout -verify\
-in $dir/csr/$DevID.csr.$format
openssl asn1parse -i -in $dir/csr/$DevID.csr.pem
# offset of start of hardwareModuleName and use that in place of 189
openssl asn1parse -i -strparse 189 -in $dir/csr/$DevID.csr.pem
openssl rand -hex $sn > $dir/serial # hex 8 is minimum, 19 is maximum
# Note 'openssl ca' does not support DER format
openssl ca -config $cfgdir/openssl-8021ARintermediate.cnf -days 375\
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-extensions 8021ar_idevid -notext -md sha256 \
-in $dir/csr/$DevID.csr.$format\
-out $dir/certs/$DevID.cert.$format
chmod 444 $dir/certs/$DevID.cert.$format
openssl verify -CAfile $dir/certs/ca-chain.cert.$format\
$dir/certs/$DevID.cert.$format
openssl x509 -noout -text -in $dir/certs/$DevID.cert.$format
openssl asn1parse -i -in $dir/certs/$DevID.cert.pem
# offset of start of hardwareModuleName and use that in place of 493
openssl asn1parse -i -strparse 493 -in $dir/certs/$DevID.cert.pem
</sourcecode>
7. Setting up a CRL for an Intermediate CA
This part provides CRL support to an Intermediate CA. In this memo
it applies to both Intermediate CAs. Set the crlDistributionPoints
as provided via the environment variables.
7.1. Create (or recreate) the CRL
It is simple to create the CRL. The CRL consists of the certificates
flagged with an R (Revoked) in index.txt:
<sourcecode> file "crl-creation.sh"
# Select which Intermediate level
intermediate=intermediate
#intermediate=8021ARintermediate
dir=$cadir/$intermediate
crl=$intermediate.crl.pem
# Create CRL file
openssl ca -config $dir/openssl-$intermediate.cnf \
-gencrl -out $dir/crl/$crl
chmod 444 $dir/crl/$crl
openssl crl -in $dir/crl/$crl -noout -text
</sourcecode>
7.2. Revoke a Certificate
Revoking a certificate is a two step process. First identify the
target certificate, examples are listed below. Revoke it then
publish a new CRL.
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<sourcecode> file "revoke-step1.sh"
targetcert=fqdn
#targetcert=clientemail
#targetcert=DevID
openssl ca -config $dir/openssl-$intermediate.cnf\
-revoke $dir/certs/$targetcert.cert.$format
</sourcecode>
Recreate the CRL using Section 7.1.
8. Setting up OCSP for an Intermediate CA
This part provides OCSP support to an Intermediate CA. In this memo
it applies to both Intermediate CAs. Set the authorityInfoAccess as
provided via the environment variables.
8.1. Create the OCSP Certificate
OCSP needs a signing certificate. This certificate must be signed by
the CA that signed the certificate being checked. The steps to
create this certificate is the similar to a Server certificate for
the CA:
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<sourcecode> file "ocsp-setup.sh"
# Select which Intermediate level
intermediate=intermediate
#intermediate=8021ARintermediate
# Optionally, password encrypt key pair
encryptkey=
#encryptkey=-aes256
# Create the key pair in Intermediate level $intermediate
cd $dir
openssl genpkey -algorithm ec -pkeyopt ec_paramgen_curve:prime256v1\
$encryptkey -pkeyopt ec_param_enc:named_curve\
-out $dir/private/$ocspurl.key.$format
chmod 400 $dir/private/$ocspurl.$format
openssl pkey -in $dir/private/$ocspurl.key.$format -text -noout
# Create CSR
commonName=
DN=$countryName$stateOrProvinceName$localityName
DN=$DN$organizationName$organizationalUnitName$commonName
echo $DN
emailaddr=postmaster@htt-consult.com
export subjectAltName="DNS:$ocspurl, email:$emailaddr"
echo $subjectAltName
openssl req -config $dir/openssl-$intermediate.cnf\
-key $dir/private/$ocspurl.key.$format \
-subj "$DN" -new -sha256 -out $dir/csr/$ocspurl.csr.$format
openssl req -text -noout -verify -in $dir/csr/$ocspurl.csr.$format
# Create Certificate
openssl rand -hex $sn > $dir/serial # hex 8 is minimum, 19 is maximum
# Note 'openssl ca' does not support DER format
openssl ca -config $dir/openssl-$intermediate.cnf -days 375\
-extensions ocsp -notext -md sha256 \
-in $dir/csr/$ocspurl.csr.$format\
-out $dir/certs/$ocspurl.cert.$format
chmod 444 $dir/certs/$ocspurl.cert.$format
openssl verify -CAfile $dir/certs/ca-chain.cert.$format\
$dir/certs/$ocspurl.cert.$format
openssl x509 -noout -text -in $dir/certs/$ocspurl.cert.$format
</sourcecode>
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8.2. Revoke a Certificate
Revoke the certificate as in Section 7.2. The OCSP responder SHOULD
detect the flag change in index.txt and, when queried respond
appropriately.
8.3. Testing OCSP with Openssl
OpenSSL provides a simple OCSP service that can be used to test the
OCSP certificate and revocation process (Note that this only reads
the index.txt to get the certificate status at startup).
In a terminal window, set variables dir and ocspurl (examples below),
then run the simple OCSP service:
<sourcecode> file "run-ocsp-server.sh"
dir=/root/ca/intermediate
ocspurl=ocsp.htt-consult.com
openssl ocsp -port 2560 -text -rmd sha256\
-index $dir/index.txt \
-CA $dir/certs/ca-chain.cert.pem \
-rkey $dir/private/$ocspurl.key.pem \
-rsigner $dir/certs/$ocspurl.cert.pem \
-nrequest 1
</sourcecode>
In another window, test out a certificate status with:
<sourcecode> file "test-ocsp-server.sh"
targetcert=fqdn
#targetcert=clientemail
#targetcert=DevID
openssl ocsp -CAfile $dir/certs/ca-chain.cert.pem \
-url http://127.0.0.1:2560 -resp_text -sha256\
-issuer $dir/certs/$intermediate.cert.pem \
-cert $dir/certs/$targetcert.cert.pem
</sourcecode>
Revoke the certificate, Section 7.2, restart the test Responder again
as above, then check the certificate status.
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9. Footnotes
Creating this document was a real education in the state of openSSL,
X.509 certificate guidance, and just general level of certificate
awareness. Here are a few short notes.
9.1. Certificate Serial Number
The certificate serial number's role is to provide yet another way to
maintain uniqueness of certificates within a pki as well as a way to
index them in a data store. It has taken on other roles, most
notably as a defense.
The CABForum guideline for a public CA is for the serial number to be
a random number at least 8 octets long and no longer than 20 bytes.
By default, openssl makes self-signed certificates with 8 octet
serial numbers. This guide uses openssl's RAND function to generate
the random value and pipe it into the -set_serial option. This
number MAY have the first bit as a ONE; the DER encoding rules
prepend such numbers with 0x00. Thus the limit of '19' for the
variable 'ns'.
A private CA need not follow the CABForum rules and can use anything
number for the serial number. For example, the root CA (which has no
security risks mitigated by using a random value) could use '1' as
its serial number. Intermediate and End Entity certificate serial
numbers can also be of any value if a strong hash, like SHA256 used
here. A value of 4 for ns would provide a sufficient population so
that a CA of 10,000 EE certificates will have only a 1.2% probability
of a collision. For only 1,000 certificates the probability drops to
0.012%.
The following was proposed on the openssl-user list as an alternative
to using the RAND function:
Keep k bits (k/8 octets) long serial numbers for all your
certificates, chose a block cipher operating on blocks of k bits, and
operate this block cipher in CTR mode, with a proper secret key and
secret starting counter. That way, no collision detection is
necessary, you'll be able to generate 2^(k/2) unique k bits longs
serial numbers (in fact, you can generate 2^k unique serial numbers,
but after 2^(k/2) you lose some security guarantees).
With 3DES, k=64, and with AES, k=128.
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9.2. Some OpenSSL config file limitations
There is a bit of inconsistency in how different parts and fields in
the config file are used. Environment variables can only be used as
values. Some fields can have null values, others cannot. The lack
of allowing null fields means a script cannot feed in an environment
variable with value null. In such a case, the field has to be
removed from the config file.
The expectation is each CA within a PKI has its own config file,
customized to the certificates supported by that CA.
9.3. subjectAltName support, or lack thereof
There is no direct openssl command line option to provide a
subjectAltName for a certificate. This is a serious limitation. Per
RFC 5280 [RFC5280] SAN is the object for providing email addresses
and DNS addresses (FQDN), yet the common practice has been to use the
commonName object within the distinguishedName object. How much of
this is due to the difficulty in creating certificates with a SAN?
Thus the only way to provide a SAN is through the config file. And
there are two approaches. This document uses an environment variable
to provide the SAN value into the config file. Another approach is
to use piping as in:
<sourcecode> file "san-creation-pipe.sh"
openssl req -new -sha256 -key domain.key\
-subj "/C=US/ST=CA/O=Acme, Inc./CN=foo.com" -reqexts SAN\
-config <(cat /etc/ssl/openssl.cnf\
<(printf "[SAN]\nsubjectAltName=DNS:foo.com,DNS:www.foo.com"))\
-out domain.csr
</sourcecode>
9.4. Certificates with only subjectAltName
Also in RFC 5280 [RFC5280] (sec 4.2.1.6): if the only subject
identity in the certificate is in subjectAltName, then Subject MUST
be empty and subjectAltName MUST be marked as critical.
This can be achieved with the variable DN=/ and subjectAltName
(example given):
DN=/
export subjectAltName=critical,email:postmaster@htt-consult.com
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9.5. DER support, or lack thereof
The long, hard-fought battle with openssl to create a full DER pki
failed. The is no facility to create a DER certificate from a DER
CSR. It just is not there in the 'openssl ca' command. Even the
'openssl x509 -req' command cannot do this for a simple certificate.
Further, there is no 'hack' for making a certificate chain as there
is with PEM. With PEM a simple concatenation of the certificates
create a usable certificate chain. For DER, some recommend using
PKCS#7 [RFC2315], where others point out that this format is poorly
support 'in the field', whereas PKCS#12 [RFC7292] works for them.
Finally, openssl does supports converting a PEM certificate to DER:
openssl x509 -outform der -in certificate.pem -out certificate.der
This should also work for the keypair. However, in a highly
constrained device it may make more sense to just store the raw
keypair in the device's very limited secure storage.
10. IANA Considerations
TBD. May be nothing for IANA.
11. Security Considerations
11.1. Adequate Randomness
Creating certificates takes a lot of random numbers. A good source
of random numbers is critical. Studies [WeakKeys] have found
excessive amount of certificates, all with the same keys due to bad
randomness on the generating systems. The amount of entropy
available for these random numbers can be tested. On Fedora/Centos
and most Linux systems use:
cat /proc/sys/kernel/random/entropy_avail
If the value is low (below 1000) check your system's randomness
source. Is rng-tools installed? Consider adding an entropy
collection service like haveged from issihosts.com/haveged.
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11.2. Key pair Theft
During the certificate creation, particularly during keypair
generation, the files are vulnerable to theft. This can be mitigate
using umask. Before using openssl, set umask:
restore_mask=$(umask -p)
umask 077
Afterwards, restore it with:
$restore_mask
or just close the shell that was used, and start a new one. (The -p
option to umask is a bash-ism)
There is nothing in these recipes that requires super-user on the
system creating the certificates. Provided that adequate randomness
is available, a virtual machine or container is entirely appropriate.
Containers tend to have better access to randomness than virtual
machines.
The scripts and configuration files and in particular, private keys,
may be kept offline on a USB key for instance, and loaded when
needed.
The OCSP server needs to be online and available to all clients that
will use the certificates. This may mean available on the Internet.
A firewall can protect the OCSP server, and port-forwards and/or ACL
rules can restrict access to just the OCSP port. OCSP artifacts are
signed by a key designed for that purpose only so do not require that
the associated CA key be available online.
Generating new CRLs, however, requires that the CA signing key be
online, which is one of the reasons for creating an intermediate CA.
12. Acknowledgments
This work was jump started by the excellent RSA pki guide by Jamie
Nguyen. The openssl-user mailing list, with its many supportive
experts; in particular: Rich Salz, Jakob Bolm, Viktor Dukhovni, and
Erwann Abalea, was of immense help as was the openssl man pages
website.
Finally, "Professor Google" was always ready to point to answers to
questions like: "openssl subjectAltName on the command line". And
the Professor, it seems, never tires of answering even trivial
questions.
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13. References
13.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
13.2. Informative References
[IEEE.802.1AR_2009]
IEEE, "IEEE Standard for Local and metropolitan area
networks - Secure Device Identity", IEEE 802.1AR-2009,
DOI 10.1109/ieeestd.2009.5367679, December 2009,
<http://ieeexplore.ieee.org/servlet/
opac?punumber=5367676>.
[RFC2315] Kaliski, B., "PKCS #7: Cryptographic Message Syntax
Version 1.5", RFC 2315, DOI 10.17487/RFC2315, March 1998,
<https://www.rfc-editor.org/info/rfc2315>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC7292] Moriarty, K., Ed., Nystrom, M., Parkinson, S., Rusch, A.,
and M. Scott, "PKCS #12: Personal Information Exchange
Syntax v1.1", RFC 7292, DOI 10.17487/RFC7292, July 2014,
<https://www.rfc-editor.org/info/rfc7292>.
[WeakKeys]
Heninger, N., Durumeric, Z., Wustrow, E., and J.
Halderman, "Detection of Widespread Weak Keys in Network
Devices", July 2011,
<https://www.usenix.org/system/files/conference/
usenixsecurity12/sec12-final228.pdf>.
Appendix A. OpenSSL config files
A.1. OpenSSL Root config file
The following is the openssl-root.cnf file contents
# OpenSSL root CA configuration file.
# Copy to `$dir/openssl.cnf`.
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[ ca ]
# `man ca`
default_ca = CA_default
[ CA_default ]
# Directory and file locations.
dir = $ENV::rootca
cadir = $ENV::cadir
format = $ENV::format
certs = $dir/certs
crl_dir = $dir/crl
new_certs_dir = $dir/newcerts
database = $dir/index.txt
serial = $dir/serial
RANDFILE = $dir/private/.rand
# The root key and root certificate.
private_key = $dir/private/ca.key.$format
certificate = $cadir/certs/ca.cert.$format
# For certificate revocation lists.
crlnumber = $dir/crlnumber
crl = $dir/crl/ca.crl.pem
crl_extensions = crl_ext
default_crl_days = 30
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
name_opt = ca_default
cert_opt = ca_default
default_days = 375
preserve = no
policy = policy_strict
copy_extensions = copy
[ policy_strict ]
# The root CA should only sign intermediate certificates that match.
# See the POLICY FORMAT section of `man ca`.
countryName = optional
stateOrProvinceName = optional
organizationName = optional
organizationalUnitName = optional
commonName = optional
[ policy_loose ]
# Allow the intermediate CA to sign a more
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# diverse range of certificates.
# See the POLICY FORMAT section of the `ca` man page.
countryName = optional
stateOrProvinceName = optional
localityName = optional
organizationName = optional
organizationalUnitName = optional
commonName = optional
[ req ]
# Options for the `req` tool (`man req`).
default_bits = 2048
distinguished_name = req_distinguished_name
string_mask = utf8only
req_extensions = req_ext
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
# Extension to add when the -x509 option is used.
x509_extensions = v3_ca
[ req_distinguished_name ]
# See <https://en.wikipedia.org/wiki/Certificate_signing_request>.
countryName = Country Name (2 letter code)
stateOrProvinceName = State or Province Name
localityName = Locality Name
0.organizationName = Organization Name
organizationalUnitName = Organizational Unit Name
commonName = Common Name
# Optionally, specify some defaults.
# countryName_default = US
# stateOrProvinceName_default = MI
# localityName_default = Oak Park
# 0.organizationName_default = HTT Consulting
# organizationalUnitName_default =
[ req_ext ]
subjectAltName = $ENV::subjectAltName
[ v3_ca ]
# Extensions for a typical CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true
# keyUsage = critical, digitalSignature, cRLSign, keyCertSign
keyUsage = critical, cRLSign, keyCertSign
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subjectAltName = $ENV::subjectAltName
[ v3_intermediate_ca ]
# Extensions for a typical intermediate CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true, pathlen:0
# keyUsage = critical, digitalSignature, cRLSign, keyCertSign
keyUsage = critical, cRLSign, keyCertSign
[ crl_ext ]
# Extension for CRLs (`man x509v3_config`).
authorityKeyIdentifier=keyid:always
[ ocsp ]
# Extension for OCSP signing certificates (`man ocsp`).
basicConstraints = CA:FALSE
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid,issuer
keyUsage = critical, digitalSignature
extendedKeyUsage = critical, OCSPSigning
</sourcecode>
A.2. OpenSSL Intermediate config file
The following is the openssl-intermediate.cnf file contents.
Remove the crlDistributionPoints to drop CRL support and
authorityInfoAccess to drop OCSP support.
# OpenSSL intermediate CA configuration file.
# Copy to `$dir/intermediate/openssl-intermediate.cnf`.
[ ca ]
# `man ca`
default_ca = CA_default
[ CA_default ]
# Directory and file locations.
dir = $ENV::intdir
cadir = $ENV::cadir
format = $ENV::format
certs = $dir/certs
crl_dir = $dir/crl
new_certs_dir = $dir/newcerts
database = $dir/index.txt
serial = $dir/serial
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RANDFILE = $dir/private/.rand
# The Intermediate key and Intermediate certificate.
private_key = $dir/private/intermediate.key.$format
certificate = $cadir/certs/intermediate.cert.$format
# For certificate revocation lists.
crlnumber = $dir/crlnumber
crl = $dir/crl/intermediate.crl.pem
crl_extensions = crl_ext
default_crl_days = $ENV::default_crl_days
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
name_opt = ca_default
cert_opt = ca_default
default_days = 375
preserve = no
policy = policy_loose
copy_extensions = copy
[ policy_strict ]
# The root CA should only sign intermediate certificates that match.
# See the POLICY FORMAT section of `man ca`.
countryName = optional
stateOrProvinceName = optional
organizationName = optional
organizationalUnitName = optional
commonName = optional
[ policy_loose ]
# Allow the intermediate CA to sign a more
# diverse range of certificates.
# See the POLICY FORMAT section of the `ca` man page.
countryName = optional
stateOrProvinceName = optional
localityName = optional
organizationName = optional
organizationalUnitName = optional
commonName = optional
UID = optional
[ req ]
# Options for the `req` tool (`man req`).
default_bits = 2048
distinguished_name = req_distinguished_name
string_mask = utf8only
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req_extensions = req_ext
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
# Extension to add when the -x509 option is used.
x509_extensions = v3_ca
[ req_distinguished_name ]
# See <https://en.wikipedia.org/wiki/Certificate_signing_request>.
countryName = Country Name (2 letter code)
stateOrProvinceName = State or Province Name
localityName = Locality Name
0.organizationName = Organization Name
organizationalUnitName = Organizational Unit Name
commonName = Common Name
UID = User ID
# Optionally, specify some defaults.
# countryName_default = US
# stateOrProvinceName_default = MI
# localityName_default = Oak Park
# 0.organizationName_default = HTT Consulting
# organizationalUnitName_default =
[ req_ext ]
subjectAltName = $ENV::subjectAltName
[ v3_ca ]
# Extensions for a typical CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true
# keyUsage = critical, digitalSignature, cRLSign, keyCertSign
keyUsage = critical, cRLSign, keyCertSign
[ v3_intermediate_ca ]
# Extensions for a typical intermediate CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true, pathlen:0
# keyUsage = critical, digitalSignature, cRLSign, keyCertSign
keyUsage = critical, cRLSign, keyCertSign
[ usr_cert ]
# Extensions for client certificates (`man x509v3_config`).
basicConstraints = CA:FALSE
nsCertType = client, email
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nsComment = "OpenSSL Generated Client Certificate"
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid,issuer
keyUsage = critical,nonRepudiation,digitalSignature,keyEncipherment
extendedKeyUsage = clientAuth, emailProtection
# uncomment the following if the ENV variables set
# crlDistributionPoints = $ENV::crlDP
# authorityInfoAccess = $ENV::ocspIAI
[ server_cert ]
# Extensions for server certificates (`man x509v3_config`).
basicConstraints = CA:FALSE
nsCertType = server
nsComment = "OpenSSL Generated Server Certificate"
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid,issuer:always
keyUsage = critical, digitalSignature, keyEncipherment
extendedKeyUsage = serverAuth
# uncomment the following if the ENV variables set
# crlDistributionPoints = $ENV::crlDP
# authorityInfoAccess = $ENV::ocspIAI
[ crl_ext ]
# Extension for CRLs (`man x509v3_config`).
authorityKeyIdentifier=keyid:always
[ ocsp ]
# Extension for OCSP signing certificates (`man ocsp`).
basicConstraints = CA:FALSE
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid,issuer
keyUsage = critical, digitalSignature
extendedKeyUsage = critical, OCSPSigning
</sourcecode>
A.3. OpenSSL 802.1AR Intermediate config file
The following is the openssl-8021ARintermediate.cnf file contents.
Remove the crlDistributionPoints to drop CRL support and
authorityInfoAccess to drop OCSP support.
# OpenSSL 8021ARintermediate CA configuration file.
# Copy to `$dir/8021ARintermediate/openssl-8021ARintermediate.cnf`.
[ ca ]
# `man ca`
default_ca = CA_default
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[ CA_default ]
# Directory and file locations.
# dir = /root/ca/8021ARintermediate
dir = $ENV::dir
cadir = $ENV::cadir
format = $ENV::format
certs = $dir/certs
crl_dir = $dir/crl
new_certs_dir = $dir/newcerts
database = $dir/index.txt
serial = $dir/serial
RANDFILE = $dir/private/.rand
# The root key and root certificate.
private_key = $dir/private/8021ARintermediate.key.$format
certificate = $dir/certs/8021ARintermediate.cert.$format
# For certificate revocation lists.
crlnumber = $dir/crlnumber
crl = $dir/crl/ca.crl.pem
crl_extensions = crl_ext
default_crl_days = $ENV::default_crl_days
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
name_opt = ca_default
cert_opt = ca_default
default_enddate = 99991231235959Z # per IEEE 802.1AR
preserve = no
policy = policy_loose
copy_extensions = copy
[ policy_strict ]
# The root CA should only sign 8021ARintermediate
# certificates that match.
# See the POLICY FORMAT section of `man ca`.
countryName = match
stateOrProvinceName = match
organizationName = match
organizationalUnitName = optional
commonName = optional
[ policy_loose ]
# Allow the 8021ARintermediate CA to sign
# a more diverse range of certificates.
# See the POLICY FORMAT section of the `ca` man page.
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countryName = optional
stateOrProvinceName = optional
localityName = optional
organizationName = optional
organizationalUnitName = optional
commonName = optional
serialNumber = optional
[ req ]
# Options for the `req` tool (`man req`).
default_bits = 2048
distinguished_name = req_distinguished_name
string_mask = utf8only
req_extensions = req_ext
# SHA-1 is deprecated, so use SHA-2 instead.
default_md = sha256
# Extension to add when the -x509 option is used.
x509_extensions = v3_ca
[ req_distinguished_name ]
# See <https://en.wikipedia.org/wiki/Certificate_signing_request>.
countryName = Country Name (2 letter code)
stateOrProvinceName = State or Province Name
localityName = Locality Name
0.organizationName = Organization Name
organizationalUnitName = Organizational Unit Name
commonName = Common Name
serialNumber = Device Serial Number
# Optionally, specify some defaults.
0.organizationName_default = HTT Consulting
organizationalUnitName_default = Devices
[ req_ext ]
subjectAltName = $ENV::subjectAltName
[ hmodname ]
hwType = OID:$ENV::hwType
hwSerialNum = FORMAT:HEX,OCT:$ENV::hwSerialNum
[ v3_ca ]
# Extensions for a typical CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true
keyUsage = critical, digitalSignature, cRLSign, keyCertSign
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[ v3_8021ARintermediate_ca ]
# Extensions for a typical
# 8021ARintermediate CA (`man x509v3_config`).
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
basicConstraints = critical, CA:true, pathlen:0
# keyUsage = critical, digitalSignature, cRLSign, keyCertSign
keyUsage = critical, cRLSign, keyCertSign
[ 8021ar_idevid ]
# Extensions for IEEE 802.1AR iDevID
# certificates (`man x509v3_config`).
basicConstraints = CA:FALSE
authorityKeyIdentifier = keyid,issuer:always
keyUsage = critical, digitalSignature, keyEncipherment
# uncomment the following if the ENV variables set
# crlDistributionPoints = $ENV::crlDP
# authorityInfoAccess = $ENV::ocspIAI
[ crl_ext ]
# Extension for CRLs (`man x509v3_config`).
authorityKeyIdentifier=keyid:always
[ ocsp ]
# Extension for OCSP signing certificates (`man ocsp`).
basicConstraints = CA:FALSE
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid,issuer
keyUsage = critical, digitalSignature
extendedKeyUsage = critical, OCSPSigning
</sourcecode>
Authors' Addresses
Robert Moskowitz
HTT Consulting
Oak Park, MI 48237
Email: rgm@labs.htt-consult.com
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Henk Birkholz
Fraunhofer SIT
Rheinstrasse 75
Darmstadt 64295
Germany
Email: henk.birkholz@sit.fraunhofer.de
Liang Xia
Huawei
No. 101, Software Avenue, Yuhuatai District
Nanjing
China
Email: Frank.xialiang@huawei.com
Michael C. Richardson
Sandelman Software Works
Email: mcr+ietf@sandelman.ca
URI: http://www.sandelman.ca/
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