Questions tagged [file-encryption]
The process of encrypting individual files on a storage medium and permitting access to the encrypted data only after proper authentication is provided.
179 questions
0
votes
0
answers
6
views
How to generate a Symmetric Key on the Secure Enclave of iOS devices and use it to sign data [migrated]
I'm working on a secure app that uses the user's master password to derive a symmetric key to encrypt all the user information. I want to add FaceId support now, and the approach I was thinking of was ...
- 1
0
votes
3
answers
82
views
Could TPM disk encryption be compromised with physical device access?
Assuming Linux is installed with full disk encryption and a passphrase-less boot via TPM, could the decryption key exchange between Linux and the TPM be intercepted if an attacker gained physical ...
- 11
0
votes
0
answers
29
views
Encryption of a small calendar
I'm working on this school project to make an encrypted period tracker for phones.
It's essentially just a list of pairs of numbers (period start, period end). Maybe we'll add some metadata later like ...
- 101
0
votes
2
answers
152
views
Is it safer to use many encryption softwares/algorithms for encrypting a file?
I am considering that there may be two ways to have a crypto broken:
The crypto algorithm may age and become vulnerable by applying advanced cryptanalysis methods, just like what happened with old ...
- 15.7k
1
vote
2
answers
164
views
Flaws in modern file encryption
Assuming AES-XTS is used for encryption, the data has to be put into the algorithm first and probably processed in RAM. Which means that the unencrypted plaintext is somewhere in the dynamic memory. ...
1
vote
1
answer
90
views
"Appendable" encryption scheme
Are there any encryption schemes that could be classified as "appendable"?
By appendable I mean being able to add new data to the end of already encrypted data, without needing to decrypt ...
- 94.5k
9
votes
3
answers
36k
views
Best way to generate a IV for AES-CBC when encrypting files?
The situation is that I want to use symmetric encryption to store some info in files. I'm going to use AES-CBC algorithm. The user is going to remember the password (meaning it will not be stored ...
CommunityBot
- 1
0
votes
0
answers
75
views
ChaCha20 1Gb encryption speed question
I wrote a simple implementation of ChaCha20 encryptor for files in C using MbedTLS implementation. The process of encryption is standard - I set key, then for each block of fixed size I generate new ...
- 1
0
votes
1
answer
921
views
Why does symmetric encryption not provide authentication and integrity? Is it only this type of encryption or cryptology in general have this issue?
Studying for Cryptology and came across a presentation regarding on "Integrity vs Authenticity" where the discussion briefly mentions how Encryption "does not provide integrity or ...
- 477
3
votes
1
answer
585
views
Is there any way to measure entropy of encryption algorithms in python?
I am new to cryptography and I am trying to find a way to measure ciphertext entropy of encryption algorithms such as AES, Chacha20, etc for a school project. Is there any way to do it on Python? I ...
- 94.5k
2
votes
1
answer
156
views
Would encrypting several layers of a filesystem be a waste?
I've been thinking about ways to improve the security of my data stored and backed up using the "3-2-1" method.
Moreover by using several layers of encryption to encrypt and decrypt a ...
CommunityBot
- 1
79
votes
2
answers
187k
views
What is safer: ZipCrypto or AES-256?
Like in title: which one of these encryption methods (ZipCrypto, AES-256) is more secure and why? I am asking about it because I'd like to know which should be preferred when compressing files with ...
10
votes
3
answers
16k
views
Encryption of big files in Java with AES/GCM
I have to encrypt big files. Say their size ranges from 500mb to several of gigabytes.
I would like to use AES/GCM/NoPadding as provided by Java 1.8 since that gives me automatic authentication and ...
-1
votes
1
answer
634
views
What's the best encryption algorithm for storing files on a server?
I'm making a cloud-based service. So, basically, my users will be able to upload files (any type of files) and they will be uploaded to a server. I am aware that I have two options:
Upload the files ...
- 101
2
votes
3
answers
223
views
Long Random Key and XOR - How Secure?
I have an application that encrypts files in the following manner (I think I can hear sighs already but bear with me):
Start with two byte arrays generated from random strings of lengths l1 and l2 (...
- 23
1
vote
1
answer
192
views
Deterministic salt for KDF
What would be recommended way to make deterministic password based file encryption?
I can use SIV mode, but KDF (like Argon) takes salt for which I could use SIV tag, but I cannot make it because I ...
- 94.5k
7
votes
4
answers
2k
views
Is Porticor's "homomorphic" key encryption something that can really be done or is it just marketing hype?
Porticor has an interesting file encryption offering for encrypting and decrypting files in an MySQL database quickly.
They are an Amazon AWS (Amazon Web Service) Partner Network technology partner ...
- 21
0
votes
2
answers
667
views
File Size Shrinks After Encryption
I am a Bitcoin enthusiast, but I have never been formally trained in the study of computer science and cryptography.
Recently, I tried a new way to encrypt my private key: I wrote it down on a paper, ...
- 46
3
votes
1
answer
637
views
Encrypt multiple chunks of data with an AEAD
Assuming that I want to encrypt a 1 GB file with e.g. AES in GCM mode or ChaCha20Poly1305.
[I'm specifically referring to the cryptography module for Python: https://cryptography.io/en/latest/hazmat/...
- 2,120
-1
votes
2
answers
2k
views
Can I 100% trust the PBKDF2(HMAC-SHA256) AES-256 CBC encryption algorithm for file encryption purposes or not, and why? (Winrar) [closed]
I am not an expert in cryptography and therefore I would like to address this problem to people who have been working on this topic for a long time and thus verify the facts from several sources.
I ...
- 49.5k
0
votes
1
answer
985
views
GnuPG - provide encryption key for AES rather than deriving it from passphrase
I'd like to encrypt a file with AES256 and provide my own 32-bytes for the encryption, rather than having GPG derive it from the passphrase.
I could not find such option, but I'm thinking about a ...
- 3,546
1
vote
1
answer
47
views
multi-user deterministic symmetric encryption
I was wondering whether there exists a symmetric encryption scheme such that
there is 1 sender and n receivers. Each receiver has 1 random and independent symmetric key. The sender knows the ...
- 165
-3
votes
1
answer
3k
views
Best complementary algorithm to AES [closed]
I'm looking to protect sensitive data from deletion by hosting it on Amazon Glacier.
I'd like to secure that data against possible hacks of Amazon by encrypting it, and I'd like for the data to be ...
2
votes
1
answer
141
views
Get Pixel Data from JPG/JPEG but still bring the integrity? [closed]
As far as I know, JPG is a lossy image compression format
Meanwhile, BMP is a generally uncompressed image format, whose file structure consists of bitmapFileHeader (14 bytes) and bitmapInfoHeader (40 ...
3
votes
2
answers
3k
views
What are best practices for long term storage (~20 years) of encrypted / sensitive files?
I have some very sensitive family files that I want to store in the cloud on multiple providers for maximal reliability and redundancy. It's essentially a large archive of all our family photos, ...
- 113
0
votes
2
answers
978
views
Hash Comparison to Detect Ransomware File Encryption
As detailed in a separate question, I thought I had a way to detect the type of ransomware that encrypts files silently, and then decrypts them on the fly, so as to prevent the user from realizing ...
- 145k
0
votes
1
answer
552
views
Is CBC mode of encryption still safe as long as it's not use to send messages over a network?
I'm still reading about the Padding Oracle attack and Side Channel attack that can be performed to decrypt cipher text encrypted with CBC though it's still not clear to me.
But base on my little ...
- 105
0
votes
1
answer
177
views
Does using ECB mode of Vigenère cipher on files (no plain text) with a key of 10,000 byte(char) is secure in today's standard?
Hi I'm fairly new to studying cryptography and I'm just curious about the security of Vigenère cipher.
Given today's powerful super computers, how secure/unsecure does Vigenère cipher can get?
let us ...
- 12.8k
0
votes
3
answers
3k
views
Encryption using ASCII instead of bits and bytes (clarification in the body)
I am new to cryptography and I am trying to understand something. I searched it on the internet, though the question is probably a simple one, couldn't find an answer. So, please don't judge me by ...
- 145k
0
votes
0
answers
24
views
How does encryption systems encrypt strings? (More clarification in the explanation) [duplicate]
I am new to cryptography and I am trying to understand something. I searched it on the internet, though the question is a simple one, couldn't find an answer. So, please don't judge me by that. Here ...
- 151k
1
vote
1
answer
146
views
Encrypt a file for random access but only after an initial read of the whole file
I'm symmetrically encrypting a file (using a random salt and a user supplied password with PKCS5S2, i.e., nothing special) and I need to be able to access it randomly. Therefore I'm using a stream ...
- 3,142
1
vote
2
answers
667
views
How can we encrypt a file to be just readable (and not writable) after decryption?
Is it possible to encrypt a file (e.g., a text document) such that when a user decrypts it, he/she be able to just read the file and not be able to change the content of the file?
I mean, the result ...
- 3,142
0
votes
0
answers
109
views
How secure is the encryption with OTP and an OneRNG?
I bought an HWRND last week. What do you think, how secure is the encryption with that and the OTP? See the OneRNG theory of operation here.
- 3,142
2
votes
1
answer
4k
views
Why use ASCII armor for file encryption?
GPG and age both offer a --armor option but what is the use case when it comes to file encryption? Surely most channels allow for transmitting binary data nowadays? ...
- 94.5k
1
vote
0
answers
43
views
Does my asymmetric/symmetric mixed file encryption pseudo code pass sanity check?
I realize this depends on my implementation and the implementation of the libraries I use. I am asking about my process assuming that the encryption libraries and my code are not flawed/compromised, ...
- 123
1
vote
1
answer
315
views
Faster alternatives to RSA trapdoor permutation
We're working on web3.0 decentralized internet, a big part of which is a decentralized file storage system where clients upload files to storage providers and pay them for the services. Storage ...
- 145k
1
vote
1
answer
299
views
How to hide multiple types of information in the same file?
I have a vague memory of watching a video of a guy "unraveling the secret story / lore" from the game Doki Doki Literature Club.
And I remember that he took a file, converted it to .txt and ...
- 26.4k
2
votes
2
answers
1k
views
How much data can we encrypt using AES 256 before changing the key?
Although this question has been answered in this link (After How Much Data Encryption (AES-256) we should change key?), I am not satisfied with the answers because the Recommendation for Block Cipher ...
- 2,118
1
vote
1
answer
210
views
Low Encrypted Entropy on PDF File
Thank you for the answers, I have edited my questions.
It is a known fact that encrypting the files increases the file entropy. You can see the average entropy values of encrypted and non-encrypted ...
- 19
6
votes
0
answers
585
views
File Encryption (EFS method)
I'm implementing (for learning purposes) a file encryptor, which uses the following method (from http://en.wikipedia.org/wiki/Encrypting_File_System). I have 3 kinds of keys: RSA public/private, AES, ...
- 1,960
4
votes
2
answers
7k
views
How to perform file encryption using 128-bit AES
I am confused. How can I encrypt a file using 128-bit Advanced Encryption Standard?
Do I need only to encrypt the file name and it's content or is there something that I need to do to encrypt it? Is ...
- 3,142
0
votes
1
answer
295
views
Making a secure file sharing scheme usable
I am trying to realize a secure file sharing scheme based on asymmetric crypto. Users will access this via browser.
In short, it works like this:
Users register and set their username and password. ...
- 151k
1
vote
3
answers
5k
views
What's the preferable encryption for large data and files in terms of speed and security other than AES?
First of all, I'm relatively new to encryption so please bear with me.
I'm looking for a way to encrypt large amounts of data only on my device, no need to transfer my encrypted files/data (10-20GB or ...
- 375
7
votes
4
answers
7k
views
Can elliptic curve (25519) be used to encrypt file?
This is probably a simple question, but I haven't been able to see it stated anywhere. Is it possible to directly encrypt a file (of any length) with some form of EC using the 25519 curve.
I know it'...
- 187
2
votes
2
answers
3k
views
Encrypt a big file in blocks with AES-GCM: how many nonce do we need?
I need to encrypt big files using AES-GCM, potentially 10 GB or more. For memory (RAM) reasons, I need to processs them by blocks (let's say 16 MB), rather than doing ...
- 553
0
votes
2
answers
159
views
How to be able to change the password to access data encrypted with AES-GCM, without reencrypting?
Let's say you need to encrypt plaintext which is 1 TB big.
You have a password pwd. This very classical AES-GCM process is ...
- 553
2
votes
1
answer
475
views
How to encrypt many files with AES-GCM, without running the key derivation function each time?
Linked question: AES encrypting multiple files
With a password, I have 100k files to encrypt. (Maybe 100k files today; or maybe 50k today, 10k tomorrow, and 40k ...
CommunityBot
- 1
2
votes
1
answer
75
views
End-to-end photo storage
I've been tasked with developing an app that will need to store photos a user takes securely, and I've been struggling to think up a method to do this.
What I was thinking so far is as follows:
When ...
- 49.5k
6
votes
3
answers
2k
views
Reusing AES-CTR Keys and IVs for File Encryption
I’m implementing some file encryption module with random-access capability and AES-CTR seems the right way to go.
I understand that reusing Keys and IVs can expose the file to ‘Stream Cipher Attacks’ ...
- 343
3
votes
1
answer
536
views
AES-CTR security if S-boxes substituion is omitted?
I understand why s-boxes are needed in general especially when ECB mode is used(because of using the same key for encryption of other blocks)but I wonder if it's ...
- 49.5k