rsa public key No such file or directory? - amazon-web-services

I'm trying to follow along the Upskillcourses.com web dev online course. In lesson 11 I'm supposed to link up cloud9 to github.
I'm trying to get the SSH key. But it's not working:
ec2-user:~/environment $ cat ~/.ssh/id_rsa.pub
cat: /home/ec2-user/.ssh/id_rsa.pub: No such file or directory
I've copied it exactly like the instructor did. I'll be honest in that I don't really know what I'm doing or how to fix. Seems like no one else is having this problem. Thanks for any help

Use ssh-keygen to create a default ssh key pair, for now without passphrase:
ssh-keygen -t rsa -C "MyEmailAddress" -f ~/.ssh/id_rsa -P ""
Then any ssh command will use by default that key.

First, check for existing SSH Key using the following command:
ls -al ~/.ssh
Check the directory listing to see if you already have a public SSH key. By default, the filenames of the public keys are one of the following: id_xxxx.pub (ex: id_rsa.pub). If you don't have an existing public and private key pair, create one using this command:
ssh-keygen -t rsa -b 4096 -C "your_email#example.com"
This creates a new ssh key, using the provided email as a label. When you're prompted to "Enter a file in which to save the key," press Enter. This accepts the default file location. At the prompt, type a secure passphrase.
If you see an existing public and private key pair listed that you would like to use to connect to GitHub, or once you are done with the above key generation step, you can add your SSH key to the ssh-agent with the following commands:
eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_rsa (Add -K option, if on MAC OS, as it will add the passphrase in your keychain when you add an ssh key to the ssh-agent.)
Source: https://docs.github.com/

This happened to me when I was simply in a directory other than the one where the SSH key was.
In order to fix this: you need to check the path to the directory where the SSH key was saved. Scroll up to where you created the key and you should see:
Your public key has been saved in /Users/userlocation/.ssh/id_rsa.pub
Now check your working directory:
pwd
If your working directory is different from the one that holds the SSH key, change the directory:
cd /Users/userlocation #find yours!
and then run the command (slightly changed):
cat .ssh/id_rsa.pub
This worked for me! (Remember to run ssh-keygen first!)

Related

Unable to SSH the Amazon EC2 instance using the .pem File. Error: " WARNING: UNPROTECTED PRIVATE KEY FILE! " [duplicate]

I'm working to set up Panda on an Amazon EC2 instance.
I set up my account and tools last night and had no problem using SSH to interact with my own personal instance, but right now I'm not being allowed permission into Panda's EC2 instance.
Getting Started with Panda
I'm getting the following error:
# WARNING: UNPROTECTED PRIVATE KEY FILE! #
Permissions 0644 for '~/.ec2/id_rsa-gsg-keypair' are too open.
It is recommended that your private key files are NOT accessible by others.
This private key will be ignored.
I've chmoded my keypair to 600 in order to get into my personal instance last night, and experimented at length setting the permissions to 0 and even generating new key strings, but nothing seems to be working.
Any help at all would be a great help!
Hm, it seems as though unless permissions are set to 777 on the directory, the ec2-run-instances script is unable to find my keyfiles.
I've chmoded my keypair to 600 in order to get into my personal instance last night,
And this is the way it is supposed to be.
From the EC2 documentation we have "If you're using OpenSSH (or any reasonably paranoid SSH client) then you'll probably need to set the permissions of this file so that it's only readable by you." The Panda documentation you link to links to Amazon's documentation but really doesn't convey how important it all is.
The idea is that the key pair files are like passwords and need to be protected. So, the ssh client you are using requires that those files be secured and that only your account can read them.
Setting the directory to 700 really should be enough, but 777 is not going to hurt as long as the files are 600.
Any problems you are having are client side, so be sure to include local OS information with any follow up questions!
Make sure that the directory containing the private key files is set to 700
chmod 700 ~/.ec2
To fix this,
you’ll need to reset the permissions back to default:
sudo chmod 600 ~/.ssh/id_rsa
sudo chmod 600 ~/.ssh/id_rsa.pub
If you are getting another error:
Are you sure you want to continue connecting (yes/no)? yes
Failed to add the host to the list of known hosts (/home/geek/.ssh/known_hosts).
This means that the permissions on that file are also set incorrectly, and can be adjusted with this:
sudo chmod 644 ~/.ssh/known_hosts
Finally, you may need to adjust the directory permissions as well:
sudo chmod 755 ~/.ssh
This should get you back up and running.
I also got the same issue, but I fix it by changing my key file permission to 600.
sudo chmod 600 /path/to/my/key.pem
The private key file should be protected. In my case i have been using the public_key authentication for a long time and i used to set the permission as 600 (rw- --- ---) for private key and 644 (rw- r-- r--) and for the .ssh folder in the home folder you will have 700 permission (rwx --- ---). For setting this go to the user's home folder and run the following command
Set the 700 permission for .ssh folder
chmod 700 .ssh
Set the 600 permission for private key file
chmod 600 .ssh/id_rsa
Set 644 permission for public key file
chmod 644 .ssh/id_rsa.pub
Change the File Permission using chmod command
sudo chmod 700 keyfile.pem
On windows, Try using git bash and use your Linux commands there. Easy approach
chmod 400 *****.pem
ssh -i "******.pem" ubuntu#ec2-11-111-111-111.us-east-2.compute.amazonaws.com
Keep your private key, public key, known_hosts in same directory and try login as below:
ssh -I(small i) "hi.pem" ec2-user#ec2-**-***-**-***.us-west-2.compute.amazonaws.com
Same directory in the sense,
cd /Users/prince/Desktop.
Now type ls command
and you should see
**.pem **.ppk known_hosts
Note: You have to try to login from the same directory or you'll get a permission denied error as it can't find the .pem file from your present directory.
If you want to be able to SSH from any directory, you can add the following to you ~/.ssh/config file...
Host your.server
HostName ec2-user#ec2-**-***-**-***.us-west-2.compute.amazonaws.com
User ec2-user
IdentityFile ~/.ec2/id_rsa-gsg-keypair
IdentitiesOnly yes
Now you can SSH to your server regardless of where the directory is by simply typing ssh your.server (or whatever name you place after "Host").
Just to brief the issue, that pem files permissions are open for every user on machine i.e any one can read and write on that file
On windows it difficult to do chmod the way I found was using a git bash.
I have followed below steps
Remove user permissions
chmod ugo-rwx abc.pem
Add permission only for that user
chmod u+rw
run chmod 400
chmod 400 abc.pem
4.Now try ssh -i for your instance
If you are on a windows machine just copy the .pem file into C drive any folder and
re-run the command.
ssh -i /path/to/keyfile.pem user#some-host
In my case, I put that file in downloads and this actually works.
Or follow this https://99robots.com/how-to-fix-permission-error-ssh-amazon-ec2-instance/
I am thinking about something else, if you are trying to login with a different username that doesn't exist this is the message you will get.
So I assume you may be trying to ssh with ec2-user but I recall recently most of centos AMIs for example are using centos user instead of ec2-user
so if you are
ssh -i file.pem centos#public_IP please tell me you aretrying to ssh with the right user name otherwise this may be a strong reason of you see such error message even with the right permissions on your ~/.ssh/id_rsa or file.pem
The solution is to make it readable only by the owner of the file, i.e. the last two digits of the octal mode representation should be zero (e.g. mode 0400).
OpenSSH checks this in authfile.c, in a function named sshkey_perm_ok:
/*
* if a key owned by the user is accessed, then we check the
* permissions of the file. if the key owned by a different user,
* then we don't care.
*/
if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
error("###########################################################");
error("# WARNING: UNPROTECTED PRIVATE KEY FILE! #");
error("###########################################################");
error("Permissions 0%3.3o for '%s' are too open.",
(u_int)st.st_mode & 0777, filename);
error("It is required that your private key files are NOT accessible by others.");
error("This private key will be ignored.");
return SSH_ERR_KEY_BAD_PERMISSIONS;
}
See the first line after the comment: it does a "bitwise and" against the mode of the file, selecting all bits in the last two octal digits (since 07 is octal for 0b111, where each bit stands for r/w/x, respectively).
sudo chmod 700 ~/.ssh
sudo chmod 600 ~/.ssh/id_rsa
sudo chmod 600 ~/.ssh/id_rsa.pub
The above 3 commands should solve the problem!
Just a note for anyone who stumbles upon this:
If you are trying to SSH with a key that has been shared with you, for example:
ssh -i /path/to/keyfile.pem user#some-host
Where keyfile.pem is the private/public key shared with you and you're using it to connect, make sure you save it into ~/.ssh/ and chmod 777.
Trying to use the file when it was saved elsewhere on my machine was giving the OP's error. Not sure if it is directly related.

Unable to SSH with Keypair

I want to SSH with a new User to my EC2 Instance using Keypair.
1. First I create a new user, a directory in the Home directory and create a new Keypair
sudo adduser Joe --disabled-password
sudo su - Joe
mkdir .ssh
chmod 700 .ssh touch .ssh/authorized_keys
chmod 600 .ssh/authorized_keys
create keypair from the AWS console and saving it on Desktop
2. Using my mac terminal, I am generating the public key
ssh-keygen -y
copy & paste the public key into Vim
vim authorised_keys
pasting the public key in 1 line
in vim using the command :w to paste
in vim command :wq
3. Done with all the set up.. Time to test it:
$ ssh -i "keypair.pem" joe#xx.xxx.xxx.xxx
ERROR
$ joe#xx.xxx.xxx.xxx's password:
What am I doing wrong here - why is it asking me for a password if I have skipped that in the very first step?
If I entered a UNIX Password when creating a the new User, its working all fine and I am able to connect.
I have followed these exact steps: https://aws.amazon.com/premiumsupport/knowledge-center/new-user-accounts-linux-instance/
Appreciate your help.

Changing EC2 pem file key pair when you have access to the EC2 instance

thank you for your time.
I have an EC2 instance, but for security reasons i need to change the pem files associated in .ssh/authorized_keys. I do understand that the public pem file goes into authorized_keys.
I do not want to mount the volume of the ec2 instance to a new one. I am considering as a last option since I do have access to the EC2 instance.
How can this be done?
I have tried:
This post Change key pair for ec2 instance the answer by Pat Mcb, but no luck.
Run this command after you download your AWS pem.
ssh-keygen -f YOURKEY.pem -y Then dump the output into
authorized_keys.
Or copy pem file to your AWS instance and execute following commands
chmod 600 YOURKEY.pem and then
ssh-keygen -f YOURKEY.pem -y >> ~/.ssh/authorized_keys
But that didn't work for me. If i follow it exactly download aws key pair key, and follow the instructions by coping the key when ssh into the instance, when i do ssh-keygen -f YOURKEY.pem -y >> ~/.ssh/authorized_keys It asks for a passphrase (never had to input one)
What i am doing is the following.
I create a new key with
ssh-keygen newpem.pem
and the .pub file i copy it in .ssh/authorized_keys
Can someone explain what i am doing incorrectly?
Note the authorized_keys file has the correct permissions.
Seems like you want to deprecate the old key and use a new key instead. These steps may help you -
Create a new key pair using the aws console and download it onto your system.
Retrieve the public key from the private key(.pem) file using the command - "ssh-keygen -y"
SSH into the instance using the old key.
Once you have access to the instance add the public key you got in step 2 into the "~/.ssh/authorized_keys" files and then save the file.
Log out of the instance and then try accessing the instance with the new key.
Hope it helps. Thank You !
You Don't even need to do all of this just mind few things with AWS EC2 you get a private key for default users . like ec2-user /ubuntu etc.
You are doing the right step
ssh-keygen -t rsa -C "your_email#example.com"
if it ask for entering any paraphrase leave it blank.
Just press to accept the default location and file name. If the .ssh directory doesn't exist, the system creates one for you.
Enter, and re-enter, if passphrase prompted
you have that key now .
Copy that key
Login to your Ec2 server.
sudo su
vim ~/.ssh/authorized_keys
paste the key.
:wq!
You'll see a key there copy it and save it as a backup somewhere.
Now paste your newly generated key in that file
and save the file.
now final step to take care is the permission, so run the following command.
sudo chmod 700 .ssh && chmod 600 .ssh/authorized_keys
Now you're good to go you.
Following are the steps to change your keypair on AWS EC2.
Login to AWS Console. Go to the Network and Security >> Keypair.
Give the name of your keypair (mykeypair) and keytype (RSA) and Private
keyformat (.pem). and click on the create keypair. It will ask you to
download .pem file in your local machine. Save it at and remember the
location.
Login to your EC2 instance and go to the .ssh. location. Create a new file called
(mykeypair.pem) and paste the content from the file we downloaded in step no.2
Run the command: sudo chmod 600 mykeypair.pem
Run the command: ssh-keygen -f mykeypair.pem -y and it will generate some
content. Copy that content. Open the file called autherized_keys and
remove all the content from it.
Paste the copied content that we have generated in the previous step. Also enter your file name (mykeypair) in last after entering space.
Reboot your instance. Go to the puttygen and generate the .ppk file
using the pem file you have downloaded from the keypair. You will be able to login your ec2 with the newly generated .ppk from putty.
Okay I figured out my problem. First of all I had been hacked by a hacker apparently because I didn't know that permitpasswordlogin: yes DISABLES pubkey authentication.... I thought it was additional security. So i used a very loose password that could be easily guessed. Anyways, I believe this because I went to the root folder and found that there was actually a new key in the root named "el patrono 1337" which actually means "the master/boss" in spanish... LOL. Anyways... So i changed that back to my secure key (made a new one actually) and then I went to login as ec2-user and couldnt, but could as root. was driving me crazy for 30 minutes or so until I realized I had accidentally changed the owner of my ec2-user folder to root and therefore ssh was not searching the ec2-user .ssh/authorized_keys when I tried to log in. Wow very glad that's over lol. And just fyi guys I don't think the hacker installed anything malicious, but I did get tipped off that he tried to ssh into other people's servers (who claim they get attacked by ssh alot according to the aws abuse report) from my machine. I'm running a very simple website with zero sensitive data etc. He didn't even block me out of the machine by disabling password authentication.(i guess he didn't want me to know?). I will build a new instance from scratch next time I want to add anything(will be pretty soon) just to be on the safe side.

Password protect a pem file

I'd like to SSH into my EC2 instance with a password protected pem file. How do I password protect a pem file? I've done this in the past but can't remember how I did it. I took a pem file generated by AWS and ran some command on it and it generated something that looked like this:
-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,<BlahBlahBlah>
<encrypted stuff is here>
-----END RSA PRIVATE KEY-----
Then when I SSH into the box, i'm specifying my password protected pem file and it asks me to enter the password before decrypting and sshing in.
I found this: https://martin.kleppmann.com/2013/05/24/improving-security-of-ssh-private-keys.html
Which tells me to use this command
ssh-keygen -t rsa -N 'super secret passphrase' -f test_rsa_key
But the resulting encrypted file (that has the correct header i'm looking for) doesn't seem to work. I'm getting "Permission denied (publickey)." when I try to ssh using that encrypted pem file. I am able to SSH into the box with the unencrypted pem file.
It is because the command you are using generates a new key pair instead of protecting your existing private key.
Try using -p option of ssh-keygen
ssh-keygen -p -f my_private_key
It will prompt you for passphrase and protect your private key.
Enter new passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved with the new passphrase.
Now if you use my_private_key in ssh, it will prompt for passphrase and it will succeed.
-p Requests changing the passphrase of a private key file instead of
creating a new private key. The program will prompt for the file
containing the private key, for the old passphrase, and twice for
the new passphrase.
You can install and use the puttygen:
sudo apt install putty
And to generate your key protected, execute this:
puttygen KEY_PAIR_PRIVATE.pem -O private-openssh -o KEY_PAIR_PRIVATE.key -P
The option -P is to set a new passphrase to private key.
P.S: You will probably need to set a permission to use the key, like this:
sudo chmod 755 KEY_PAIR_PRIVATE.key
And finally you can access your aws instance safely:
ssh -i KEY_PAIR_PRIVATE.key ubuntu#IP_EC2_INSTANCE_OR_HOSTNAME

Creating user in ubuntu from AWS

Using AWS (Amazon Web Services) I have created an Ubuntu 16.10 instance and I am able to login using a pem file like this:
ssh -i key.pem ubuntu#52.16.73.14.54
After I am logged, I can see that I am able to execute:
sudo su
(with no password), however the file /etc/sudoers does NOT contain any reference to the user current user: ubuntu.
How can I create another user with exactly the same behavior (without touching the sudoers file) from terminal in a NON interactive way?
I tried:
sudo useradd -m -c "adding a test user" -G sudo,adm -s /bin/bash testuser
But after I become "testuser" if I invoke:
sudo su
I have to provide a password. Which is exactly the way I want to avoid.
You can't do this without touching sudo, beacuse the ubuntu user is given passwordless access specifically.
$ for group in `groups ubuntu`; do sudo grep -r ^[[:space:]]*[^#]*$group[[:space:]] /etc/sudoers* ; done
/etc/sudoers.d/90-cloud-init-users:ubuntu ALL=(ALL) NOPASSWD:ALL
/etc/sudoers.d/90-cloud-init-users:ubuntu ALL=(ALL) NOPASSWD:ALL
/etc/sudoers:%sudo ALL=(ALL:ALL) ALL
But what you can do is create a new sudoers file without touching any existing files. sudo is typically configured these days to read all the configurations in a directiory, usually /etc/sudoers.d/, preceisely so that one failing config doesn't effect the rest of sudo.
In your case, you might want to give an admin group sudoless access rather than your user. Then you can add access in the future to other users without changing sudo config.