使用 openssl 命令行構建 CA 及證書
根 CA
為根 CA 創建一個目錄,並進入:
mkdir -p ~/SSLCA/root/
cd ~/SSLCA/root/
生成根 CA 的 8192 位長的 RSA 密鑰:
openssl genrsa -out rootca.key 8192
輸出類似如下:
Generating RSA private key, 8192 bit long modulus
.........++
....................................................................................................................++
e is 65537 (0x10001)
如果你要用密碼保護這個密鑰,在命令行添加選項 -aes256
。
創建 SHA-256 自簽名的根 CA 證書 ca.crt
;你需要為你的根 CA 提供識別信息:
openssl req -sha256 -new -x509 -days 1826 -key rootca.key -out rootca.crt
輸出類似如下:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
--Country Name (2 letter code) [AU]:CN
State or Province Name (full name) [Some-State]:Beijing
Locality Name (eg, city) []:Chaoyang dist.
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Linux.CN
Organizational Unit Name (eg, section) []:Linux.CN CA
Common Name (e.g. server FQDN or YOUR name) []:Linux.CN Root CA
Email Address []:ca@linux.cn
創建幾個文件, 用於該 CA 存儲其序列號:
touch certindex
echo 1000 > certserial
echo 1000 > crlnumber
創建 CA 的配置文件,該文件包含 CRL 和 OCSP 終端的存根。
# vim ca.conf
[ ca ]
default_ca = myca
[ crl_ext ]
issuerAltName=issuer:copy
authorityKeyIdentifier=keyid:always
[ myca ]
dir = ./
new_certs_dir = $dir
unique_subject = no
certificate = $dir/rootca.crt
database = $dir/certindex
private_key = $dir/rootca.key
serial = $dir/certserial
default_days = 730
default_md = sha1
policy = myca_policy
x509_extensions = myca_extensions
crlnumber = $dir/crlnumber
default_crl_days = 730
[ myca_policy ]
commonName = supplied
stateOrProvinceName = supplied
countryName = optional
emailAddress = optional
organizationName = supplied
organizationalUnitName = optional
[ myca_extensions ]
basicConstraints = critical,CA:TRUE
keyUsage = critical,any
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
keyUsage = digitalSignature,keyEncipherment,cRLSign,keyCertSign
extendedKeyUsage = serverAuth
crlDistributionPoints = @crl_section
subjectAltName = @alt_names
authorityInfoAccess = @ocsp_section
[ v3_ca ]
basicConstraints = critical,CA:TRUE,pathlen:0
keyUsage = critical,any
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
keyUsage = digitalSignature,keyEncipherment,cRLSign,keyCertSign
extendedKeyUsage = serverAuth
crlDistributionPoints = @crl_section
subjectAltName = @alt_names
authorityInfoAccess = @ocsp_section
[ alt_names ]
DNS.0 = Linux.CN Root CA
DNS.1 = Linux.CN CA Root
[crl_section]
URI.0 = http://pki.linux.cn/rootca.crl
URI.1 = http://pki2.linux.cn/rootca.crl
[ ocsp_section ]
caIssuers;URI.0 = http://pki.linux.cn/rootca.crt
caIssuers;URI.1 = http://pki2.linux.cn/rootca.crt
OCSP;URI.0 = http://pki.linux.cn/ocsp/
OCSP;URI.1 = http://pki2.linux.cn/ocsp/
如果你要設置一個特定的證書起止時間,添加下述內容到 [myca]
。
# format: YYYYMMDDHHMMSS
default_enddate = 20191222035911
default_startdate = 20181222035911
創建1號中級 CA
生成中級 CA 的私鑰
openssl genrsa -out intermediate1.key 4096
生成其 CSR:
openssl req -new -sha256 -key intermediate1.key -out intermediate1.csr
輸出類似如下:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
--Country Name (2 letter code) [AU]:CN
State or Province Name (full name) [Some-State]:Beijing
Locality Name (eg, city) []:Chaoyang dist.
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Linux.CN
Organizational Unit Name (eg, section) []:Linux.CN CA
Common Name (e.g. server FQDN or YOUR name) []:Linux.CN Intermediate CA
Email Address []:
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
請確保中級 CA 的主題名(CN,Common Name)和根 CA 的不同。
使用根 CA 為你創建的中級 CA 的 CSR 簽名:
openssl ca -batch -config ca.conf -notext -in intermediate1.csr -out intermediate1.crt
輸出類似如下:
Using configuration from ca.conf
Check that the request matches the signature
Signature ok
The Subject's Distinguished Name is as follows
countryName :PRINTABLE:'CN'
stateOrProvinceName :ASN.1 12:'Beijing'
localityName :ASN.1 12:'chaoyang dist.'
organizationName :ASN.1 12:'Linux.CN'
organizationalUnitName:ASN.1 12:'Linux.CN CA'
commonName :ASN.1 12:'Linux.CN Intermediate CA'
Certificate is to be certified until Mar 30 15:07:43 2017 GMT (730 days)
Write out database with 1 new entries
Data Base Updated
生成 CRL (包括 PEM 和 DER 兩種格式):
openssl ca -config ca.conf -gencrl -keyfile rootca.key -cert rootca.crt -out rootca.crl.pem
openssl crl -inform PEM -in rootca.crl.pem -outform DER -out rootca.crl
每次使用該 CA 簽名證書後都需要生成 CRL。
如果需要的話,你可以 撤銷 這個中級證書:
openssl ca -config ca.conf -revoke intermediate1.crt -keyfile rootca.key -cert rootca.crt
配置1號中級 CA
給該中級 CA 創建新目錄,並進入:
mkdir ~/SSLCA/intermediate1/
cd ~/SSLCA/intermediate1/
從根 CA 那邊複製這個中級 CA 的證書和私鑰:
cp ../root/intermediate1.key ./
cp ../root/intermediate1.crt ./
創建索引文件:
touch certindex
echo 1000 > certserial
echo 1000 > crlnumber
創建一個新的 ca.conf
:
# vim ca.conf
[ ca ]
default_ca = myca
[ crl_ext ]
issuerAltName=issuer:copy
authorityKeyIdentifier=keyid:always
[ myca ]
dir = ./
new_certs_dir = $dir
unique_subject = no
certificate = $dir/intermediate1.crt
database = $dir/certindex
private_key = $dir/intermediate1.key
serial = $dir/certserial
default_days = 365
default_md = sha1
policy = myca_policy
x509_extensions = myca_extensions
crlnumber = $dir/crlnumber
default_crl_days = 365
[ myca_policy ]
commonName = supplied
stateOrProvinceName = supplied
countryName = optional
emailAddress = optional
organizationName = supplied
organizationalUnitName = optional
[ myca_extensions ]
basicConstraints = critical,CA:FALSE
keyUsage = critical,any
subjectKeyIdentifier = hash
authorityKeyIdentifier = keyid:always,issuer
keyUsage = digitalSignature,keyEncipherment
extendedKeyUsage = serverAuth
crlDistributionPoints = @crl_section
subjectAltName = @alt_names
authorityInfoAccess = @ocsp_section
[ alt_names ]
DNS.0 = Linux.CN Intermidiate CA 1
DNS.1 = Linux.CN CA Intermidiate 1
[ crl_section ]
URI.0 = http://pki.linux.cn/intermediate1.crl
URI.1 = http://pki2.linux.cn/intermediate1.crl
[ ocsp_section ]
caIssuers;URI.0 = http://pki.linux.cn/intermediate1.crt
caIssuers;URI.1 = http://pki2.linux.cn/intermediate1.crt
OCSP;URI.0 = http://pki.linux.cn/ocsp/
OCSP;URI.1 = http://pki2.linux.cn/ocsp/
修改 [alt_names]
小節為你所需的 替代主題名 。如果不需要就刪除引入它的 subjectAltName = @alt_names
行。
如果你需要指定起止時間,添加如下行到 [myca]
中。
# format: YYYYMMDDHHMMSS
default_enddate = 20191222035911
default_startdate = 20181222035911
生成一個空的 CRL (包括 PEM 和 DER 兩種格式):
openssl ca -config ca.conf -gencrl -keyfile intermediate1.key -cert intermediate1.crt -out intermediate1.crl.pem
openssl crl -inform PEM -in intermediate1.crl.pem -outform DER -out intermediate1.crl
創建最終用戶證書
我們使用新的中級 CA 來生成最終用戶的證書。為每個你需要用此 CA 簽名的最終用戶證書重複這些步驟。
mkdir ~/enduser-certs
cd ~/enduser-certs
生成最終用戶的私鑰:
openssl genrsa -out enduser-example.com.key 4096
生成最終用戶的 CSR:
openssl req -new -sha256 -key enduser-example.com.key -out enduser-example.com.csr
輸出類似如下:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
--Country Name (2 letter code) [AU]:CN
State or Province Name (full name) [Some-State]:Shanghai
Locality Name (eg, city) []:Xuhui dist.
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Example Inc
Organizational Unit Name (eg, section) []:IT Dept
Common Name (e.g. server FQDN or YOUR name) []:example.com
Email Address []:
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
用1號中級 CA 簽名最終用戶的證書:
cd ~/SSLCA/intermediate1
openssl ca -batch -config ca.conf -notext -in ~/enduser-certs/enduser-example.com.csr -out ~/enduser-certs/enduser-example.com.crt
輸出類似如下:
Using configuration from ca.conf
Check that the request matches the signature
Signature ok
The Subject's Distinguished Name is as follows
countryName :PRINTABLE:'CN'
stateOrProvinceName :ASN.1 12:'Shanghai'
localityName :ASN.1 12:'Xuhui dist.'
organizationName :ASN.1 12:'Example Inc'
organizationalUnitName:ASN.1 12:'IT Dept'
commonName :ASN.1 12:'example.com'
Certificate is to be certified until Mar 30 15:18:26 2016 GMT (365 days)
Write out database with 1 new entries
Data Base Updated
生成 CRL (包括 PEM 和 DER 兩種格式):
cd ~/SSLCA/intermediate1/
openssl ca -config ca.conf -gencrl -keyfile intermediate1.key -cert intermediate1.crt -out intermediate1.crl.pem
openssl crl -inform PEM -in intermediate1.crl.pem -outform DER -out intermediate1.crl
每次使用該 CA 簽名證書後都需要生成 CRL。
如果需要的話,你可以撤銷revoke這個最終用戶證書:
cd ~/SSLCA/intermediate1/
openssl ca -config ca.conf -revoke ~/enduser-certs/enduser-example.com.crt -keyfile intermediate1.key -cert intermediate1.crt
輸出類似如下:
Using configuration from ca.conf
Revoking Certificate 1000.
Data Base Updated
將根證書和中級證書連接起來創建證書鏈文件:
cat ../root/rootca.crt intermediate1.crt > ~/enduser-certs/enduser-example.com.chain
將這些文件發送給最終用戶:
enduser-example.com.crt
enduser-example.com.key
enduser-example.com.chain
你也可以讓最終用戶提供他們中級的 CSR 文件,而只發回給他們 這個 .crt
文件。不要從伺服器上刪除它們,否則就不能撤銷了。
校驗證書
你可以通過如下命令使用證書鏈來驗證最終用戶證書:
cd ~/enduser-certs
openssl verify -CAfile enduser-example.com.chain enduser-example.com.crt
enduser-example.com.crt: OK
你也可以用 CRL 來校驗它。首先將 PEM CRL 連接到證書鏈文件:
cd ~/SSLCA/intermediate1
cat ../root/rootca.crt intermediate1.crt intermediate1.crl.pem > ~/enduser-certs/enduser-example.com.crl.chain
校驗證書:
cd ~/enduser-certs
openssl verify -crl_check -CAfile enduser-example.com.crl.chain enduser-example.com.crt
如果該證書未撤銷,輸出如下:
enduser-example.com.crt: OK
如果撤銷了,輸出如下:
enduser-example.com.crt: CN = example.com, ST = Beijing, C = CN, O = Example Inc, OU = IT Dept
error 23 at 0 depth lookup:certificate revoked
本文轉載來自 Linux 中國: https://github.com/Linux-CN/archive