Monthly Archives: April 2019

How to convert JKS file to KEY file for Apache

Leave a reply

Article explaining how to convert java keystore jks into PEM formatted certificate or key file for Apache configuration

JKS to KEY

Scenario: I have a key file (*.jks) and CSR file generated in using keytool command i.e. in java. I wanted to convert this jks file to *.key file so that it can be used in Apache webserver configuration.

Read how to create java Keystore file *.jks if you want to know how to create CSR using java keytool.

Solution :

JKS file is Keystore used in java. You need to follow the below steps to get your unencrypted key file. Its a two-step process :

  1. Import key data from keystore to PKC12 format
  2. Convert PKCS12 key to un-encrypted PEM

Import key data from keystore to PKC12 format

We will import key data from jks Keystore to new Keystore in PKC12 format using keytool command where –

  • -srckeystore : Your jks file
  • -destkeystore : Name of new keystore to create
  • -deststoretype : Obv has to be PKCS12

You need to provide a password of the source Keystore and also set a new password to the new Keystore.

[root@kerneltalks ~]# keytool -importkeystore -srckeystore kerneltalks.com.jks -destkeystore keystore.pkcs12 -deststoretype PKCS12
Importing keystore kerneltalks.com.jks to keystore.p12...
Enter destination keystore password:
Re-enter new password:
Enter source keystore password:
Entry for alias server successfully imported.
Import command completed:  1 entries successfully imported, 0 entries failed or cancelled

Convert PKCS12 key to un-encrypted PEM

We now need to convert this PKCS12 key in PEM format so that it can be used in the Apache configuration.

[root@kerneltalks ~]# openssl pkcs12 -in keystore.pkcs12  -nodes -nocerts -out kerneltalks.com.key
Enter Import Password:
MAC verified OK

Now verify your private key file.

[root@kerneltalks ~]# file kerneltalks.com.key
kerneltalks.com.key: ASCII text
[root@kerneltalks ~]# file kerneltalks.com.jks
kerneltalks.com.jks: Java KeyStore
[root@kerneltalks ~]# cat kerneltalks.com.key
Bag Attributes
    friendlyName: server
    localKeyID: 54 69 6D 65 20 31 35 35 36 32 30 38 36 31 33 32 36 34
Key Attributes: <No Attributes>
-----BEGIN PRIVATE KEY-----
MIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQCLc1bmTilYhwRZ
14CBZEN+TGrzsPAbdg3zBW9nSmnRQRS9qWYLkqSBF1zcTj6T8P5BtDr6MOr7pivZ
DXbS9RPUcJk9JwRskj+FGrOP8qquzCOHXvzgxZNKNYDNdz+YzT3Hz0n4bbhYwYCW
qo+768GSnCJS+i3m+xztTB1hIq881UK4cbujTkm42L3i8YCzycy+Y6my+z4to4yf
kn8t9v2b/18m432+hz/dA+h7aVF8sdterc6c+XC35zdk8kkly+TZPn9DY9piBuPb
DPe/CPa+BTUwHQW/22HcAUwd/T0PWi2MeDWja2KtGrCPB/Tg07ZC8oGnXPF9pADg
ydHR+MHrAgMBAAECggEAD/RQOuUyYciAvO6k6yjXd/myOtNBhULKccVra3veA2zY
vKJG5IgQfhx4KVRiYHawAEBohvtVxxjJ53lc4OHdNO70+UQfg3RwBAB8DroKwRjl
77T0ZZr1MQZSCC/efNLugI+8vMmAz9bDqXk2HJ/qc6WdX7Tzz3tnYdbVfamENwdb
7+w3isHa+XhsJdR9IrpPL35mf2HSeW2WgOMku/GWIdEcCGdxm0cZTx7X1JNBrimm
zAp1+5xVx3ptgrtRYYAihFjQLNvhp5twyAdK2mB4iOpU35c3KPWD2HqNfp0MYPNq
eRlqEdIxFimXMnRw4zSA7GuaSADv5ddS60529KK2IQKBgQC/fK99E/8iSk3UtZvz
/5PUSabnAUK73Z0N5QLZfGwSWF51q0zmxfVQInHXIGIFeqkjt8EOEiOIXi7XyA+c
FG8KBKIkXoeJ/Rzxskzp1yG0L2EePJbUSnxtL4PTqlVCW6H5/C6V4icaMx4nC1Od
4vWmAqtRKBCdF5fMEOKWcn6t8wKBgQC6bqAwQUe4WvcnySN2vjMJiLDPm4RpnnuJ
o1s3pkPDeXaDI+2nD8NJT6GaskJsQhuq9ikdecDljqJIoSi7hCqHO75pUDPWdHIG
QMiyR2OB4NOOCvFf9FuVEz7JMWa7vk+KVgtgaaX3wG7vqsaYJcQ/VgsBqtKDSKS6
j4gaJiECKQKBgEjxcVQfOvBQB8gAinDvKdwTVm3nEAnKiNpTI7u/ZteyLAF9CKVc
QW+OP3loj45wxF+jzvnSNRDsd8GhJzkYm5fgXfemvtD0x4LWne/yEJe3+LHw+K/T
1AQvtnL6DtJhX5l/1CsqZCTZ1iGfcfHSFCtyFtqqfXGqHBwTTo1q/hC7AoGBALbW
2/+3ZjFl9VNtrnw8WS2Wg2F4skorhhkcvs87HuZM72/6Ao9/pBT4JhPjk8U8qIno
1bX0vLvmQT5d3+bX3iW28C203MIMfe+oBazi2rJ73r9F+CgVLORtdXw4GPsz0Cpp
7MpnksACWEpxAEgjce5z4mOGNuNOkU/uiJqsnl7RAoGAb5JbI7nBMJbUQp6QaZjN
tn1ZIaYEF+wyx2XR12iaqWG8RGwLcayZ55wjlAgO+qx3aYoheU4BTlqQiZMP+ytp
vUfV2rbexdqkvQAefg4kFkrFtOMQ7gzVWoIbWIhd5xyEtonvX3lqkm+c/kpxcruP
xe2Elr6dfovdXXadgIBDiSA=
-----END PRIVATE KEY-----

To use this key file in Apache configuration you need to strip off a header. Delete all parts till -----BEGIN PRIVATE KEY----- and save the file. Now you are good to use this *.key file in Apache SSL configuration.

How to export certificate from JKS file

As an addon to this post, I will walk you through how to export a certificate from java Keystore to PEM format. This is again two-step exercise as below –

Export certificate in binary

You read from the Keystore file certificate associated with alias and export it to a binary file. I used alias as server while creating this jks file hence options are –

  • -export : To export data. This is same as exportcert in newer versions
  • -alias : Enter same alias you used while creating this java key file
  • -file : Destination binary file in which you will export
  • -keystore : Your jks key file
[root@kerneltalks ~]# keytool -export -alias server -file kerneltalks.com.der -keystore kerneltalks.com.jks
Enter keystore password:
Certificate stored in file <kerneltalks.com.der>

Warning:
The JKS keystore uses a proprietary format. It is recommended to migrate to PKCS12 which is an industry standard format using "keytool -importkeystore -srckeystore kerneltalks.com.jks -destkeystore kerneltalks.com.jks -deststoretype pkcs12".

Convert exported certificate data to PEM format

Now we will convert certificate binary to PEM format using below command where –

  • -in : Input binary means exported file in last command
  • -out : Output file in PEM format

Now verify your certificate file.

[root@kerneltalks ~]# openssl x509 -inform der -in kerneltalks.com.der -out certificate.pem
[root@kerneltalks ~]# file certificate.pem
certificate.pem: PEM certificate
[root@kerneltalks ~]# cat  certificate.pem
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

How to add UUID entry in /etc/fstab in Linux

2 Replies

In this short tutorial, we will walk you through how to get UUID of the filesystem so that it can be used in /etc/fstab.

UUID entry in /etc/fstab

First of all, keep in mind you need to format your logical volume to get UUID registered in the kernel for it. Logical volume without filesystem on it won’t be having UUID attached to it. If you are using partitioning volume manager then disk partitions will have PARTUUID (partition UUID) even if you don’t format them. But it’s not useful in /etc/fstab since fstab deals with formatted partitions.

How to find UUID for logical volume

For this tutorial consider below setup –

[root@kerneltalks ~]# lsblk
NAME           MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
xvda           202:0    0    8G  0 disk
└─xvda1        202:1    0    8G  0 part /
xvdf           202:80   0    1G  0 disk
└─datavg-lvol0 253:0    0 1020M  0 lvm

We have one logical volume named lvol0 in the volume group datavg and now we need to find UUID for it. Use command blkid and grep for your logical volume name to get your desired output –

[root@kerneltalks ~]# blkid |grep lvol0
/dev/mapper/datavg-lvol0: UUID="5caaee32-c3d3-429e-bad7-2898cf923805" TYPE="ext4"

You can see you have UUID for the lvol you mentioned and along with it also sourced its filesystem type which is ext4.

How to add UUID entry in /etc/fstab

Lets add this UUID entry in /etc/fstab using format –

<UUID> <mount directory> <FS type> <mount options> <dump> <pass>

So our entry will look like –

UUID=5caaee32-c3d3-429e-bad7-2898cf923805  /data  ext4  defaults 0 0

We are mounting it on /data directory with default mount options and no fschecks. Add this entry to fstab and run mount -a and mount point established!

[root@kerneltalks ~]# df -Ph /data1
Filesystem                Size  Used Avail Use% Mounted on
/dev/mapper/datavg-lvol0  988M  2.6M  919M   1% /data

How to find UUID for disk partition

Consider below setup for finding UUID for disk partition.

[root@kerneltalks ~]# lsblk
NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
xvda    202:0    0    8G  0 disk
└─xvda1 202:1    0    8G  0 part /
xvdf    202:80   0    1G  0 disk
└─xvdf1 202:81   0 1023M  0 part

Here we have one non-root disk /dev/xvdf with one full partition /dev/xvdf1 on it. And it’s not yet formatted with any filesystem. Now if you run blkid command you will find PARTUUID for this partition.

[root@kerneltalks ~]# blkid |grep xvdf1
/dev/xvdf1: PARTUUID="6d123669-01"

I format it so that I can mount it on the directory. And after formatting it with the ext4 filesystem here is UUID making an entry!

[root@kerneltalks ~]# blkid | grep xvdf1
/dev/xvdf1: UUID="05ba450d-9c60-43f1-9dd1-8b6f89857961" TYPE="ext4" PARTUUID="6d123669-01"

You can compare this output with earlier one and you can see after formatting with ext4 you get UUID which can be used in /etc/fstab as explained earlier in this post.