一般情況下，如果能找到可用的證書，就可以直接使用，只不過會因證書的某些信息不正確或與部署證書的主機不匹配而導致瀏覽器提示證書無效，但這並不影響使用。
需要手工生成證書的情況有：
- 找不到可用的證書
- 需要配置雙向SSL，但缺少客戶端證書
- 需要對證書作特別的定製
首先，無論是在Linux下還是在Windows下的Cygwin中，進行下面的操作前都須確認已安裝OpenSSL軟件包。
1. 創建根證書密鑰文件(自己做CA)root.key：
openssl genrsa -des3 -out root.key
輸出內容爲：
[lenin@archer ~]$ openssl genrsa -des3 -out root.key
Generating RSA private key, 512 bit long modulus
……………..++++++++++++
..++++++++++++
e is 65537 (0×10001)
Enter pass phrase for root.key: ← 輸入一個新密碼
Verifying – Enter pass phrase for root.key: ← 重新輸入一遍密碼
2. 創建根證書的申請文件root.csr：
openssl req -new -key root.key -out root.csr
輸出內容爲：
[lenin@archer ~]$ openssl req -new -key root.key -out root.csr
Enter pass phrase for root.key: ← 輸入前面創建的密碼
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 ← 國家代號，中國輸入CN
State or Province Name (full name) [Some-State]:BeiJing ← 省的全名，拼音
Locality Name (eg, city) []:BeiJing ← 市的全名，拼音
Organization Name (eg, company) [Internet Widgits Pty Ltd]:MyCompany Corp. ← 公司英文名
Organizational Unit Name (eg, section) []: ← 可以不輸入
Common Name (eg, YOUR name) []: ← 此時不輸入
Email Address []:[email protected] ← 電子郵箱，可隨意填Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []: ← 可以不輸入
An optional company name []: ← 可以不輸入
3. 創建一個自當前日期起爲期十年的根證書root.crt：
openssl x509 -req -days 3650 -sha1 -extensions v3_ca -signkey root.key -in root.req -out root.crt
輸出內容爲：
[lenin@archer ~]$ openssl x509 -req -days 3650 -sha1 -extensions v3_ca -signkey root.key -in root.csr -out root.crt
Signature ok
subject=/C=CN/ST=BeiJing/L=BeiJing/O=MyCompany Corp./[email protected]
Getting Private key
Enter pass phrase for root.key: ← 輸入前面創建的密碼
4. 創建服務器證書密鑰server.key：
openssl genrsa –des3 -out server.key 2048
輸出內容爲：
[lenin@archer ~]$ openssl genrsa -out server.key 2048
Generating RSA private key, 2048 bit long modulus
….+++
…………………………………………..+++
e is 65537 (0×10001)運行時會提示輸入密碼,此密碼用於加密key文件(參數des3便是指加密算法,當然也可以選用其他你認爲安全的算法.),以後每當需讀取此文件(通過openssl提供的命令或API)都需輸入口令.如果覺得不方便,也可以去除這個口令,但一定要採取其他的保護措施!
去除key文件口令的命令:
openssl rsa -in server.key -out server.key
5.創建服務器證書的申請文件server.csr：
openssl req -new -key server.key -out server.csr
輸出內容爲：
[lenin@archer ~]$ openssl req -new -key server.key -out server.req
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 ← 國家名稱，中國輸入CN
State or Province Name (full name) [Some-State]:BeiJing ← 省名，拼音
Locality Name (eg, city) []:BeiJing ← 市名，拼音
Organization Name (eg, company) [Internet Widgits Pty Ltd]:MyCompany Corp. ← 公司英文名
Organizational Unit Name (eg, section) []: ← 可以不輸入
Common Name (eg, YOUR name) []:www.mycompany.com ← 服務器主機名，若填寫不正確，瀏覽器會報告證書無效，但並不影響使用
Email Address []:[email protected] ← 電子郵箱，可隨便填Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []: ← 可以不輸入
An optional company name []: ← 可以不輸入
6. 創建自當前日期起有效期爲期兩年的服務器證書server.crt：
openssl x509 -req -days 730 -sha1 -extensions v3_req -CA root.crt -CAkey root.key -CAserial root.srl -CAcreateserial -in server.csr -out server.crt
輸出內容爲：
[lenin@archer ~]$ openssl x509 -req -days 730 -sha1 -extensions v3_req -CA root.crt -CAkey root.key -CAcreateserial -in server.csr -out server.crt
Signature ok
subject=/C=CN/ST=BeiJing/L=BeiJing/O=MyCompany Corp./CN=www.mycompany.com/[email protected]
Getting CA Private Key
Enter pass phrase for root.key: ← 輸入前面創建的密碼
7. 創建客戶端證書密鑰文件client.key：
openssl genrsa -des3 -out client.key 2048
輸出內容爲：
[lenin@archer ~]$ openssl genrsa -des3 -out client.key 2048
Generating RSA private key, 2048 bit long modulus
……………………………………………………………………………..+++
……………………………………………………………………………………………………….+++
e is 65537 (0×10001)
Enter pass phrase for client.key: ← 輸入一個新密碼
Verifying – Enter pass phrase for client.key: ← 重新輸入一遍密碼
8. 創建客戶端證書的申請文件client.csr：
openssl req -new -key client.key -out client.csr
輸出內容爲：
[lenin@archer ~]$ openssl req -new -key client.key -out client.csr
Enter pass phrase for client.key: ← 輸入上一步中創建的密碼
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 ← 國家名稱，中國輸入CN
State or Province Name (full name) [Some-State]:BeiJing ← 省名稱，拼音
Locality Name (eg, city) []:BeiJing ← 市名稱，拼音
Organization Name (eg, company) [Internet Widgits Pty Ltd]:MyCompany Corp. ← 公司英文名
Organizational Unit Name (eg, section) []: ← 可以不填
Common Name (eg, YOUR name) []:Lenin ← 自己的英文名，可以隨便填
Email Address []:[email protected] ← 電子郵箱，可以隨便填Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []: ← 可以不填
An optional company name []: ← 可以不填
9. 創建一個自當前日期起有效期爲兩年的客戶端證書client.crt：
openssl x509 -req -days 730 -sha1 -extensions v3_req -CA root.crt -CAkey root.key -CAserial root.srl -CAcreateserial -in client.csr -out client.crt
輸出內容爲：
[lenin@archer ~]$ openssl x509 -req -days 730 -sha1 -extensions v3_req -CA root.crt -CAkey root.key -CAcreateserial -in client.csr -out client.crt
Signature ok
subject=/C=CN/ST=BeiJing/L=BeiJing/O=MyCompany Corp./CN=www.mycompany.com/[email protected]
Getting CA Private Key
Enter pass phrase for root.key: ← 輸入上面創建的密碼
10. 將客戶端證書文件client.crt和客戶端證書密鑰文件client.key合併成客戶端證書安裝包client.pfx：
openssl pkcs12 -export -in client.crt -inkey client.key -out client.pfx
輸出內容爲：
[lenin@archer ~]$ openssl pkcs12 -export -in client.crt -inkey client.key -out client.pfx
Enter pass phrase for client.key: ← 輸入上面創建的密碼
Enter Export Password: ← 輸入一個新的密碼，用作客戶端證書的保護密碼，在客戶端安裝證書時需要輸入此密碼
Verifying – Enter Export Password: ← 確認密碼
11. 保存生成的文件備用，其中server.crt和server.key是配置單向SSL時需要使用的證書文件，client.crt是配置雙向SSL時需要使用的證書文件，client.pfx是配置雙向SSL時需要客戶端安裝的證書文件
.crt文件和.key可以合到一個文件裏面，把2個文件合成了一個.pem文件（直接拷貝過去就行了）