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Questions tagged [encryption]

Encryption is transforming information through a cipher to protect it from unauthorized access.

Encryption is the process of taking some information (the plain text), and transforming it (usually with a cypher and a key) so that it is secure. Assuming a sufficiently strong cypher and key have been chosen, this cyphertext can be shared widely, without the information being compromised.

The reverse of Encryption is Decryption, where the process is reversed (normally by someone holding the key and cypher details) to return the information.

See the Wikipedia Page for more details.

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Create a public SSH key from the private key?

Let's suppose I have a SSH key, but I've deleted the public key part. I have the private key part. Is there some way I can regenerate the public key part?
Amandasaurus
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I have a keypair. How do I determine the key length?

Using OpenSSL from the command line in Linux, is there some way to examine a key (either public or private) to determine the key size?
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How to create an SHA-512 hashed password for shadow?

The previous SF questions I've seen have lead to answers that produce MD5 hashed password. Does anyone have a suggestion on to produce an SHA-512 hashed password? I'd prefer a one liner instead of a script but, if a script is the only solution,…
Belmin Fernandez
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Is STARTTLS less safe than TLS/SSL?

In Thunderbird (and I assume in many other clients, too) I have the option to choose between "SSL/TLS" and "STARTTLS". As far as I understand it, "STARTTLS" means in simple words "encrypt if both ends support TLS, otherwise don't encrypt the…
Foo Bar
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What is a good solution to encrypt some files in unix?

I am looking for a utility to encrypt certain directories in Linux. I am not looking for any full disk encryption services, but simply to encrypt a few directories for the purposes of storing files in the cloud. Once retrieving them, I should have…
Peter
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GPG - why am I encrypting with subkey instead of primary key?

When encrypting a file to send to a collaborator, I see this message: gpg: using subkey XXXX instead of primary key YYYY Why would that be? I've noticed that when they send me an encrypted file, it also appears to be encrypted towards my subkey…
Michael H.
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Is enforcing encryption for SMTP a good idea (yet)?

I am running an email server which is currently set up to use TLS if possible, when sending and receiving emails. When you read in the documentation about this, there is also the option to enforce TLS and not accept plain text transmission of…
comfreak
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Why do my two ssh public keys have the same beginning?

I was updating the authorized_keys file on my server with the public key for the new laptop I got and I was surprised to discover that the two public keys began the same: # key 1 ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ.... # # key 2 ssh-rsa…
Gabe Durazo
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Is data always encrypted in IPv6 communications?

I can't seem to get a straight answer to this quesion. Wikipedia says "IPsec is an integral part of the base protocol suite in IPv6," but does that mean that ALL communications are always encrypted, or does it mean that encryption is optional, but…
alan
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Is MySQL port 3306 encrypted, and if no, how can I encrypt it?

I am working through a security audit for a system at my work and one of the requirements is to encrypt all traffic through public/unprotected networks. Since we are accessing the MySQL database (over port 3306) on one of our external servers from…
Stephen RC
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ZFS RAID and LUKS encryption in Linux

I'm planning to setup a set of 3x 2TB 7200rpm drives as a LUKS-encrypted Z-RAID pool in Linux (for a NAS solution). My understanding of the problem at hand is that the only way to achieve this is to luksFormat every physical device and then…
MasterM
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Whats a good way to encrypt a mysql database, and is it worth it?

I know I can encrypt particular fields of a database, but I'm interested in encrypting every field of the database. I want to make sure no one who gains access to a mysql shell but who does not have access to a decryption key cannot read anything…
Snitse
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How to convert a unencrypted EBS to be encrypted

I have a number of older EBS volumes that are not encrypted. In satisfying new corporate security measures, all data needs to be "encrypted at rest" so I need to convert all of the volumes to be encrypted. What is the best way to accomplish this?
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What impact does full hard drive encryption have on performance?

We have HP notebooks here at work, and it is policy to have HP's hard drive encryption turned on to protect client databases and IP in the case of loss/theft. I was wondering if there was any evidence of a performance hit in this situation? The…
csjohnst
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How can I disable encryption on openssh?

I'm having performance problems using openssh (server) and putty (client) combination to use a remote webproxy. I'd like to disable encryption and test the results to see if it makes a difference. How can i do that? Is there anything i can modify in…
Mark
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