Will using CTR mode with unique IVs, but only one password for encrypting multiple files, leak data or keys?

I’m working on a project to encrypt many files with a single password.

The steps I will employ to encrypt the files are:

  1. user will execute a command similar to tool --encrypt --recurse directories/to/recurse and-other-files.txt
  2. the user will be prompted for a password
  3. two 64 byte crypto random salts and a 16 byte crypto random IV will be generated
  4. no 2 files will ever use the same salts or IV
  5. each individual salt will be combined with the password to create to 2 separate argon2id keys
  6. one key will be 32 bytes long and is used for the AES-256 cipher block
  7. the other will be 64 bytes long and will be used as the key for a sha-512 hmac
  8. the resulting encrypted file will be written as 2ByteVersion:64ByteHMACSalt:64ByteCipherBlockSalt:16ByteIV:EncryptedData:64ByteHMACSignature

I believe this would result in a reasonably secure, set of encrypted files. My main concern though, is that because of the way that users will use this tool, there is a good chance that they will accidentally encrypt small, easily guessed files.

And since CTR mode doesn’t require padding, anyone with access to the encrypted file will know the length of the plaintext file. It seems that CTR mode is considered secure for files, provided the IV is unique for each encryption run and the file is authenticated.

Is there a chance that the cipher key, HMAC key, or password could be derived through a known plaintext attack from enough small guessable files? Are there any other glaring flaws in my methodology that could leak data?

Does Mode ordering break the system, and if so how?

Some time ago, I encountered the following statement from Reddit, which makes me think that either I’m not understanding how modes work, or there’s something incomplete or wrong in the statement (I did ask the author of the statement for follow-up clarification, but received none). I realise it is unfortunate that I’m quoting someone else saying a thing a long time ago and asking the Stack to help me achieve understanding of how Modes work and whether that work is flawed, but I think basing my question about Modes on this quote makes it more grounded in the context that caused my doubts.

Modes, as presented in ARRPG are ripe for abuse. In fact you can abuse them without even planning on min-maxing a character. Two players can take the same modes and just change the order and end up with characters with one of them having +1 to +2 shifts over the other on most of their skills.

The key is to take as your last mode one that gives improvements. If you take this as your first mode it gives few top skills, but by taking a skill heavy first mode and improvement heavy last mode you can push more skills higher.

I keep re-reading the chargen pages and have trouble grasping how does Mode ordering work so as to produce disparities in total sum of skills of a character. The way I read it, order seems irrelevant since of the two Modes, the highest one is taken. I’m also not understanding the distinction between a ‘skill heavy’ and ‘improvement heavy’ Mode. What could be meant by that?

Am I missing something in that process? Am I missing something in the surrounding process? Or is the statement missing/misunderstanding something about either?

Netplan Bridge Stuck in Degraded Mode

I’m trying to add a Bridge on 18.04 Server VM on Hyper-V with LXD Installed and the bridge never comes up and never gets an IP Address. Hopefully someone sees what I’m doing wrong.

network:   version: 2   renderer: networkd   ethernets:     eth0:       dhcp4: no       dhcp6: no   bridges:     br0:       interfaces:         - eth0       dhcp4: yes       dhcp6: no 

networkd status

IDX LINK             TYPE               OPERATIONAL SETUP   1 lo               loopback           carrier     unmanaged   2 eth0             ether              carrier     configured   3 br0              ether              degraded    configuring   4 lxdbr0           ether              routable    unmanaged   6 vethC0L5GN       ether              degraded    unmanaged 

networkd log

● systemd-networkd.service - Network Service    Loaded: loaded (/lib/systemd/system/systemd-networkd.service; enabled; vendor preset: enabled)    Active: active (running) since Sun 2019-10-13 15:40:13 UTC; 7min ago      Docs: man:systemd-networkd.service(8)  Main PID: 12869 (systemd-network)    Status: "Processing requests..."     Tasks: 1 (limit: 4915)    CGroup: /system.slice/systemd-networkd.service            └─12869 /lib/systemd/systemd-networkd  Oct 13 15:40:13 lxd1 systemd-networkd[12869]: eth0: Link is not managed by us Oct 13 15:40:13 lxd1 systemd-networkd[12869]: lo: Link is not managed by us Oct 13 15:40:13 lxd1 systemd-networkd[12869]: vethC0L5GN: Link is not managed by us Oct 13 15:40:13 lxd1 systemd-networkd[12869]: lxdbr0: Link is not managed by us Oct 13 15:40:13 lxd1 systemd-networkd[12869]: eth0: Lost carrier Oct 13 15:40:13 lxd1 systemd-networkd[12869]: br0: Lost carrier Oct 13 15:40:13 lxd1 systemd-networkd[12869]: eth0: IPv6 successfully disabled Oct 13 15:40:13 lxd1 systemd-networkd[12869]: eth0: Gained carrier Oct 13 15:40:13 lxd1 systemd-networkd[12869]: eth0: Configured Oct 13 15:40:13 lxd1 systemd-networkd[12869]: br0: Gained carrier 

If I change back to this and reboot everything comes up fine.

network:   version: 2   renderer: networkd   ethernets:     eth0:       dhcp4: yes       dhcp6: no 

“You are in emergency mode” error on booting Ubuntu 18.04

I use ubuntu 18.04 , on boot I get the following error:



I try journalctl To see the log

journalctl -xb 

I saw that there were two red lines in the logs :

log response:

log response

and With my searches, I realized I had to use fsck

fsck -f /dev/sda5 

and I get this response :

fsck -f /dev/sda5 results:

fsck -f /dev/sda5 results

and I added -n to fsck command

fsck -nf /dev/sd5  

and I get the following results :

fsck -nf results:

fsck -nf results

Reporting trident token or other indications of a user in compatibility mode within Google Analytics

I have noticed that the number of users reporting to be using Internet Explorer 9 is high (2%) within browser & OS in Google Analytics. Reviewing the user agent it’s clear a higher number of these are running Internet Explorer 11 in compatibility Mode. It appears google analytics would represent the following user as IE9. However, the trident value of 7 indicates they are using Internet Explorer 11. What’s my browser example

DeviceType Mozilla/5.0+(compatible;+MSIE+9.0;+Windows+NT+10.0;+Win64;+x64;+Trident/7.0;+Touch) 

I’ve seen older threads stating that it’s not possible to report browser by the trident token or if the the user is in compatibility mode.

Is this still the case? Are there other tools within google analytics that could give an accurate represent of the IE 9 usage?

Fail to enter suspend mode after upgrade

I am currently running Ubuntu 18.04.3 LTS on a desktop machine (8 year old). After a recent software upgrade, when I long-pressed the power button and then pressed on the suspend button, the computer failed to enter the suspend mode. The fan was still running and a running light was still on. Before the upgrade, everything was running smoothly; the fan will stop and the running light will turn blinking.

Is there anything I should configure to restore the old behaviour?

MSHYBRID / NVIDIA Optimus mode for partitioning GPU work?

I purchased a high-end laptop with an RTX 2070 (not max q) to help run my pytorch models. This laptop comes with a BIOS feature called MSHYBRID (Same as NVIDIA Optimus by another name). I read some posts about MSHYBRID mode. To enable it, I had to add GRUB_GFXPAYLOAD_LINUX=1920*1080 to grub. After that, I now have the option in my NVIDIA Settings to switch between discrete (NVIDIA) and Intel integrated graphics. If I switch from one to the other, it makes me logout and then back in to switch GPUs.

However, it’s my understanding that MSHYBRID/Optimus allows Intel to drive the display and NVIDIA to be used secondarily. This is what I want. I want Intel to drive my display and PyTorch/Tensorflow to be able to use my RTX 2070 for compute purposes. That way, I can train models with no disruption to things like video playback. When I run nvidia-smi with MSHYBRID enabled, it says:


This doesn’t sound like what I want. I continued installing CUDA on this new machine anyway. I run:

import torch torch.cuda.get_device_name(0) 

output: 'GeForce RTX 2070'

So I switch to MSHYBRID mode, logout and back in. Trouble starts:

>>> import torch >>> torch.cuda.is_available() False >>> torch.cuda.device_count() 0 

I’m pretty sure this would work in Windows. Often, this feature is used in order to power the display by Intel while simultaneously rendering via the NVIDIA GPU. I believe in Windows it is software controlled. Am I missing something – some linux project to make it work? Can it work?

SharePoint Word Docs showing open in safe mode message

I am working with SP on prem 2019, the office files are set to launch in client apps. For some reason, when clicking on word files from SharePoint, it first tries to launch Word Client and then doesn’t do anything.

If I click again on the same document, then I see below: enter image description here

the issue only appears to be happening with Word files, excel files are opening fine in client, if anyone came across this, please share thoughts. Installed office version is 2016.