Wiki source code of OpenSSL
Version 2.1 by Sebastian Marsching on 2022/05/29 13:38
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| author | version | line-number | content |
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1.1 | 1 | {{toc/}} |
| 2 | |||
| 3 | # Managing a Public Key Infrastructure (PKI) with OpenSSL | ||
| 4 | |||
| 5 | ## Creating the Certificate Authority (CA) | ||
| 6 | |||
| 7 | First we create an RSA key and certificate request for the CA: | ||
| 8 | |||
| 9 | ```bash | ||
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2.1 | 10 | openssl req -out ca.csr -keyout ca.key -newkey rsa:2048 |
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1.1 | 11 | ``` |
| 12 | |||
| 13 | In the next step, we self-sign this certificate request in order to create the CA certificate: | ||
| 14 | |||
| 15 | ```bash | ||
| 16 | openssl x509 -in ca.csr -out ca.crt -days 9131 -signkey ca.key -req -extfile ca.cnf -set_serial 0 | ||
| 17 | ``` | ||
| 18 | |||
| 19 | The configuration file `ca.cnf` used in this example has the following content: | ||
| 20 | |||
| 21 | basicConstraints=critical,CA:TRUE | ||
| 22 | |||
| 23 | ## Creating and Signing a Server Certificate | ||
| 24 | |||
| 25 | In order to create the certificate request and RSA key, we use the following command: | ||
| 26 | |||
| 27 | ```bash | ||
| 28 | openssl req -out cert.csr -keyout cert.key -nodes -newkey rsa:2048 -sha256 | ||
| 29 | ``` | ||
| 30 | |||
| 31 | In this example, we do not protect the private key with a password (`-nodes` option). If you do not want to request a SHA2-signed certificate but prefer a traditional (SHA1 signed) certificate instead, remove the `-sha256` option. | ||
| 32 | |||
| 33 | The certificate request is signed with the following command: | ||
| 34 | |||
| 35 | ```bash | ||
| 36 | openssl x509 -in cert.csr -out cert.crt -days 731 -req -extfile server.cnf -CA ca.crt -CAkey ca.key -CAserial serial | ||
| 37 | ``` | ||
| 38 | |||
| 39 | For the first certificate being signed, the option `-CAcreateserial` has to be added to the command line, so that OpenSSL creates the files holding the serials. The configuration file `server.cnf` used in this example has the following content: | ||
| 40 | |||
| 41 | basicConstraints=critical,CA:FALSE | ||
| 42 | extendedKeyUsage=serverAuth | ||
| 43 | nsCertType=server | ||
| 44 | |||
| 45 | In order to add subject alternative names to the certificate, the following line can be added to the `server.cnf` file: | ||
| 46 | |||
| 47 | subjectAltName=DNS:name1.example.com,DNS:name2.example.com | ||
| 48 | |||
| 49 | ## Signing a Client Certificate | ||
| 50 | |||
| 51 | The steps are exactly the same as for a server certificate. However, instead of `server.cnf` a different configuration file is used: | ||
| 52 | |||
| 53 | basicConstraints=critical,CA:FALSE | ||
| 54 | extendedKeyUsage=clientAuth | ||
| 55 | nsCertType=client | ||
| 56 | |||
| 57 | # Importing a Certificate into the Java Keystore | ||
| 58 | |||
| |
2.1 | 59 | See [[KeyStore|doc:Development.Java.KeyStore.WebHome]]. |
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1.1 | 60 | |
| 61 | ### Creating a PKCS#12 file | ||
| 62 | |||
| 63 | The following command can be used to create a PKCS#12 file containing the certificate, its private key and the root-certificate. Such a file can be used to import the certificate in software (e.g. web browser or e-mail client for client certificates): | ||
| 64 | |||
| 65 | ```bash | ||
| 66 | cat ca.crt cert.crt | openssl pkcs12 -inkey cert.key -out cert.p12 -export | ||
| 67 | ``` |