Selbstsigniertes Zertifikat erstellen

Submitted by admin on So, 11.12.2016 - 11:17

1438416147892-x509.certificate.icon.png

Das folgende Skript erzeugt ein selbstsigniertes Zertifikat mit einem RSA Key. Es können mehrere Hostnamen angegeben werden, der erste Hostname erscheint im /CN, alle anderen Hostnamen erscheinen als X509v3 Subject Alternative Names, so dass das Zertifikat für alle Hostnamen gültig ist. Ist EC_ALGO nicht gesetzt, dann wird ein RSA Zertifikat erstellt, ansonsten wird ein Key auf Basis elliptischer Kurven erstellt.

#!/bin/bash

# comment EC_ALGO if you want RSA
#EC_ALGO="prime256v1"
#EC_ALGO="secp521r1"

# Cert is DAYS valid
DAYS=3650

# Other attributes you may need
SUBJ_PREFIX="/C=DE/ST=Hessen/L=Taunusstein/O=Christian Felsing"


##############################################
# No more user changeable vars
# from here
##############################################

HOSTNAME=$1

usage() {
  echo "usage: $0 <hostname> [<more hostnames>...]"
  exit 1
}

if [ -z "$HOSTNAME" ]; then
  usage
fi

OPENSSLCNF="/tmp/openssl.$.cf"

declare -a ARGV
ARGV=("$@")

cat > "$OPENSSLCNF" <<EOF
#
# 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

# 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
subjectAltName = @alt_names

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

[alt_names]
DNS.1 = $HOSTNAME
EOF

ARGC=$#
for (( i=0; i<$ARGC; i++ )); do
  ALTNAME=${ARGV[${i}]}
  echo "DNS.${i} = ${ALTNAME}" >> "$OPENSSLCNF"
done

cat >> "$OPENSSLCNF" <<EOF

[ v3_ca ]

subjectAltName = @alt_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

# 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)
EOF

umask 077
OUTFILE=${HOSTNAME}.crt

if [ -z "$EC_ALGO" ]; then
  openssl req -x509 -config "$OPENSSLCNF" -nodes -newkey rsa:4096 -sha256 -subj "${SUBJ_PREFIX}/CN=${HOSTNAME}" -keyout ${HOSTNAME}.key -out ${OUTFILE} -days $DAYS
else
  openssl ecparam -out "${HOSTNAME}.key" -name ${EC_ALGO} -genkey
  openssl req -x509 -new -config "$OPENSSLCNF" -nodes -key "${HOSTNAME}.key" -sha256 -subj "${SUBJ_PREFIX}/CN=${HOSTNAME}" -out ${OUTFILE} -days $DAYS
fi

chmod 644 "${OUTFILE}"
umask 022

rm -f "$OPENSSLCNF"

Das Skript erzeugt eine temporäre openssl.cnf Datei.