1

I am trying to implement a better set of self signed certificates at my company. What I want is this:

  • All certificates are signed by one root certificate, so developers can trust just this root certificate
  • Child certificate are wildcards of the base url, and the url themselves.

For example, I have a root certificate, and a child certificate signed by it, with Subject Alternative Name of acme.local, and *.acme.local.

I have achieved both of these goals independently, but I cannot get them together. To sign a certificate with a root, I have to build a CSR and then the certificate separately, but I cannot work out how to get the req and x509 to work together with the subjectAltName extension. Whatever I try, I get the cryptic error message:

Error Loading extension section default
140698802165664:error:22097082:X509 V3 routines:DO_EXT_NCONF:unknown extension name:v3_conf.c:124:
140698802165664:error:22098080:X509 V3 routines:X509V3_EXT_nconf:error in extension:v3_conf.c:93:name=HOME, value=.

Can anybody help me achieve multiple subjectAltNames with a root certificate?

For what it's worth, I have near total control of the toolchain.


Edit:

As requested, the openssl.cnf I am using is attached. It's the one that came out of /etc/pki/tls/openssl.cnf, with a few modifications, but I'm not 100% sure what's going on with the whole file. My guess is that the areas correspond somehow to the different commands, and I think I need to specify the v3 extension (for SAN) in both the request and the ca parts, but I'm not sure how to make them correspond, or whether I need to do that if copy_extensions is turned on, because then I feel like they might be in the CSR. Anyway, SSL is complicated and anyone who says otherwise is lying or selling something.

#
# OpenSSL example configuration file.
# This is mostly being used for generation of certificate requests.
#

# This definition stops the following lines choking if HOME isn't
# defined.
HOME            = .
RANDFILE        = $ENV::HOME/.rnd

# Extra OBJECT IDENTIFIER info:
#oid_file       = $ENV::HOME/.oid
oid_section     = new_oids

# To use this configuration file with the "-extfile" option of the
# "openssl x509" utility, name here the section containing the
# X.509v3 extensions to use:
# extensions        = 
# (Alternatively, use a configuration file that has only
# X.509v3 extensions in its main [= default] section.)

[ new_oids ]

# We can add new OIDs in here for use by 'ca', 'req' and 'ts'.
# Add a simple OID like this:
# testoid1=1.2.3.4
# Or use config file substitution like this:
# testoid2=${testoid1}.5.6

# Policies used by the TSA examples.
tsa_policy1 = 1.2.3.4.1
tsa_policy2 = 1.2.3.4.5.6
tsa_policy3 = 1.2.3.4.5.7

####################################################################
[ ca ]
default_ca  = CA_default        # The default ca section

####################################################################
[ CA_default ]

dir     = /etc/pki/CA       # Where everything is kept
certs       = $dir/certs        # Where the issued certs are kept
crl_dir     = $dir/crl      # Where the issued crl are kept
database    = $dir/index.txt    # database index file.
#unique_subject = no            # Set to 'no' to allow creation of
                # several ctificates with same subject.
new_certs_dir   = $dir/newcerts     # default place for new certs.

certificate = $dir/cacert.pem   # The CA certificate
serial      = $dir/serial       # The current serial number
crlnumber   = $dir/crlnumber    # the current crl number
                # must be commented out to leave a V1 CRL
crl     = $dir/crl.pem      # The current CRL
private_key = $dir/private/cakey.pem# The private key
RANDFILE    = $dir/private/.rand    # private random number file

x509_extensions = usr_cert      # The extentions to add to the cert

# Comment out the following two lines for the "traditional"
# (and highly broken) format.
name_opt    = ca_default        # Subject Name options
cert_opt    = ca_default        # Certificate field options

# Extension copying option: use with caution.
# copy_extensions = copy
copy_extensions = copy

# Extensions to add to a CRL. Note: Netscape communicator chokes on V2 CRLs
# so this is commented out by default to leave a V1 CRL.
# crlnumber must also be commented out to leave a V1 CRL.
# crl_extensions    = crl_ext

default_days    = 365           # how long to certify for
default_crl_days= 30            # how long before next CRL
default_md  = sha256        # use SHA-256 by default
preserve    = no            # keep passed DN ordering

# A few difference way of specifying how similar the request should look
# For type CA, the listed attributes must be the same, and the optional
# and supplied fields are just that :-)
policy      = policy_match

# For the CA policy
[ policy_match ]
countryName     = match
stateOrProvinceName = match
organizationName    = match
organizationalUnitName  = optional
commonName      = supplied
emailAddress        = optional

# For the 'anything' policy
# At this point in time, you must list all acceptable 'object'
# types.
[ policy_anything ]
countryName     = optional
stateOrProvinceName = optional
localityName        = optional
organizationName    = optional
organizationalUnitName  = optional
commonName      = supplied
emailAddress        = optional

####################################################################
[ req ]
default_bits        = 2048
default_md      = sha256
default_keyfile     = privkey.pem
distinguished_name  = req_distinguished_name
attributes      = req_attributes
x509_extensions = v3_ca # The extentions to add to the self signed cert

# Passwords for private keys if not present they will be prompted for
# input_password = secret
# output_password = secret

# This sets a mask for permitted string types. There are several options. 
# default: PrintableString, T61String, BMPString.
# pkix   : PrintableString, BMPString (PKIX recommendation before 2004)
# utf8only: only UTF8Strings (PKIX recommendation after 2004).
# nombstr : PrintableString, T61String (no BMPStrings or UTF8Strings).
# MASK:XXXX a literal mask value.
# WARNING: ancient versions of Netscape crash on BMPStrings or UTF8Strings.
string_mask = utf8only

req_extensions = v3_req # The extensions to add to a certificate request

[ req_distinguished_name ]
countryName         = Country Name (2 letter code)
countryName_default     = XX
countryName_min         = 2
countryName_max         = 2

stateOrProvinceName     = State or Province Name (full name)
#stateOrProvinceName_default    = Default Province

localityName            = Locality Name (eg, city)
localityName_default        = Default City

0.organizationName      = Organization Name (eg, company)
0.organizationName_default  = Default Company Ltd

# we can do this but it is not needed normally :-)
#1.organizationName     = Second Organization Name (eg, company)
#1.organizationName_default = World Wide Web Pty Ltd

organizationalUnitName      = Organizational Unit Name (eg, section)
#organizationalUnitName_default =

commonName          = Common Name (eg, your name or your server\'s hostname)
commonName_max          = 64

emailAddress            = Email Address
emailAddress_max        = 64

# SET-ex3           = SET extension number 3

[ req_attributes ]
challengePassword       = A challenge password
challengePassword_min       = 4
challengePassword_max       = 20

unstructuredName        = An optional company name

[ usr_cert ]

# These extensions are added when 'ca' signs a request.

# This goes against PKIX guidelines but some CAs do it and some software
# requires this to avoid interpreting an end user certificate as a CA.

basicConstraints=CA:FALSE

# Here are some examples of the usage of nsCertType. If it is omitted
# the certificate can be used for anything *except* object signing.

# This is OK for an SSL server.
# nsCertType            = server

# For an object signing certificate this would be used.
# nsCertType = objsign

# For normal client use this is typical
# nsCertType = client, email

# and for everything including object signing:
# nsCertType = client, email, objsign

# This is typical in keyUsage for a client certificate.
# keyUsage = nonRepudiation, digitalSignature, keyEncipherment

# This will be displayed in Netscape's comment listbox.
nsComment           = "OpenSSL Generated Certificate"

# PKIX recommendations harmless if included in all certificates.
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer

# This stuff is for subjectAltName and issuerAltname.
# Import the email address.
# subjectAltName=email:copy
# An alternative to produce certificates that aren't
# deprecated according to PKIX.
# subjectAltName=email:move

# Copy subject details
# issuerAltName=issuer:copy

#nsCaRevocationUrl      = http://www.domain.dom/ca-crl.pem
#nsBaseUrl
#nsRevocationUrl
#nsRenewalUrl
#nsCaPolicyUrl
#nsSslServerName

# This is required for TSA certificates.
# extendedKeyUsage = critical,timeStamping

[ v3_req ]

# Extensions to add to a certificate request

basicConstraints = CA:FALSE
keyUsage = nonRepudiation, digitalSignature, keyEncipherment

[ v3_ca ]

subjectAltName = @alternative_names

# Extensions for a typical CA


# PKIX recommendation.

subjectKeyIdentifier=hash

authorityKeyIdentifier=keyid:always,issuer

# This is what PKIX recommends but some broken software chokes on critical
# extensions.
#basicConstraints = critical,CA:true
# So we do this instead.
basicConstraints = CA:true

# Key usage: this is typical for a CA certificate. However since it will
# prevent it being used as an test self-signed certificate it is best
# left out by default.
# keyUsage = cRLSign, keyCertSign
keyUsage = digitalSignature, keyEncipherment

# Some might want this also
# nsCertType = sslCA, emailCA

# Include email address in subject alt name: another PKIX recommendation
# subjectAltName=email:copy
# Copy issuer details
# issuerAltName=issuer:copy

# DER hex encoding of an extension: beware experts only!
# obj=DER:02:03
# Where 'obj' is a standard or added object
# You can even override a supported extension:
# basicConstraints= critical, DER:30:03:01:01:FF

[ crl_ext ]

# CRL extensions.
# Only issuerAltName and authorityKeyIdentifier make any sense in a CRL.

# issuerAltName=issuer:copy
authorityKeyIdentifier=keyid:always

[ proxy_cert_ext ]
# These extensions should be added when creating a proxy certificate

# This goes against PKIX guidelines but some CAs do it and some software
# requires this to avoid interpreting an end user certificate as a CA.

basicConstraints=CA:FALSE

# Here are some examples of the usage of nsCertType. If it is omitted
# the certificate can be used for anything *except* object signing.

# This is OK for an SSL server.
# nsCertType            = server

# For an object signing certificate this would be used.
# nsCertType = objsign

# For normal client use this is typical
# nsCertType = client, email

# and for everything including object signing:
# nsCertType = client, email, objsign

# This is typical in keyUsage for a client certificate.
# keyUsage = nonRepudiation, digitalSignature, keyEncipherment

# This will be displayed in Netscape's comment listbox.
nsComment           = "OpenSSL Generated Certificate"

# PKIX recommendations harmless if included in all certificates.
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer

# This stuff is for subjectAltName and issuerAltname.
# Import the email address.
# subjectAltName=email:copy
# An alternative to produce certificates that aren't
# deprecated according to PKIX.
# subjectAltName=email:move

# Copy subject details
# issuerAltName=issuer:copy

#nsCaRevocationUrl      = http://www.domain.dom/ca-crl.pem
#nsBaseUrl
#nsRevocationUrl
#nsRenewalUrl
#nsCaPolicyUrl
#nsSslServerName

# This really needs to be in place for it to be a proxy certificate.
proxyCertInfo=critical,language:id-ppl-anyLanguage,pathlen:3,policy:foo

####################################################################
[ tsa ]

default_tsa = tsa_config1   # the default TSA section

[ tsa_config1 ]

# These are used by the TSA reply generation only.
dir     = ./demoCA      # TSA root directory
serial      = $dir/tsaserial    # The current serial number (mandatory)
crypto_device   = builtin       # OpenSSL engine to use for signing
signer_cert = $dir/tsacert.pem  # The TSA signing certificate
                # (optional)
certs       = $dir/cacert.pem   # Certificate chain to include in reply
                # (optional)
signer_key  = $dir/private/tsakey.pem # The TSA private key (optional)

default_policy  = tsa_policy1       # Policy if request did not specify it
                # (optional)
other_policies  = tsa_policy2, tsa_policy3  # acceptable policies (optional)
digests     = sha1, sha256, sha384, sha512  # Acceptable message digests (mandatory)
accuracy    = secs:1, millisecs:500, microsecs:100  # (optional)
clock_precision_digits  = 0 # number of digits after dot. (optional)
ordering        = yes   # Is ordering defined for timestamps?
            # (optional, default: no)
tsa_name        = yes   # Must the TSA name be included in the reply?
            # (optional, default: no)
ess_cert_id_chain   = no    # Must the ESS cert id chain be included?
            # (optional, default: no)
            #

[ alternative_names ]

DNS.1 = acme.loc
DNS.2 = *.acme.loc

And the output of openssl version is OpenSSL 1.0.1e-fips 11 Feb 2013. It's the one packaged with CentOS 7.1.

  • It would probably help if you posted the contents of the relevant openssl config files. You may simply be formatting the SAN field wrong. – Ryan Bolger Nov 20 '15 at 18:00
  • Please post openssl -version\ – kubanczyk Nov 20 '15 at 23:42
1

It's best to have three different openssl.cnf files on your system. You cannot use a single file for all the operations. And yes, the syntax is a nightmare.

  1. The default one should be restored and kept intact, so the default behavior is not broken in future.
  2. Copy it to your own openssl-test-ca.cnf and modify it accordingly to your needs.
  3. Copy it to your own openssl-san.cnf and modify it accordingly to your needs.

Now, for every operation which involves your own root (or req for it) use:

openssl command -config /.../openssl-test-ca.cnf  more options

For every operation which involves your SAN client cert (or req for it) use the openssl-san.cnf. And correct the subjectAltName = @alternative_names to appear in [v3_req] and [usr_cert] in the openssl-san.cnf file.

  • I had, of course copied the default openssl.cnf and edited that. I was using a shell script to dynamically add the SAN at the end. I believe, as well that x509 requires openssl x509 -extfile. Because consistency. – Max Bucknell Nov 21 '15 at 13:00
  • Yes, but I'm going to read the OpenSSL Cookbook and answer this question myself. Thanks for getting me started! – Max Bucknell Nov 23 '15 at 10:15
  • @MaxBucknell please check the last sentence of my answer - I've updated it – kubanczyk Nov 23 '15 at 10:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.