passing yes argument while scp command - linux

I am facing an issue when I run simply these commands.
The remote server want to pass yes to add the key in RSA file because first time connection established with scp.
commands are given below
#!/bin/bash
scp -P58222 root#IP:/root/K /N
/usr/bin/expect -c 'expect "\n" { expect "Are you sure you want to continue connecting (yes/no)?" }'
send "yes\r"
expect "$ "
send "exit\r"
Actually I have to pass yes in my script while asking
The authenticity of host 'ip address (ip address)' can't be established.
RSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx.
Are you sure you want to continue connecting (yes/no)?
Are you sure you want to continue connecting (yes/no)?
how can I get rid of this problem?
with
scp -o StrictHostKeyChecking=no
it is still asking.

scp -o StrictHostKeyChecking=no root#IP:/root/K
Obviously, this isn't a very secure solution. Works for one-shots where you're not concerned about man in the middle, though.

For me, this works:
yes | scp -r /opt/MyFiles root#<MyNewServerIP>:/opt/MyFiles
Regards. =)

Probably the best way to do this would be to use the following command before your scp command:
ssh-keyscan -H ${SSH_HOST} >> ~/.ssh/known_hosts
This will add the SSH_HOST to your known hosts and scp will not complain. Substitute ${SSH_HOST} for the IP address you are trying to connect to.

Related

Execute remote SSH command and evaluate this command on remote side

Let's consider a following code:
CMD=echo $(hostname --fqdn) >> /tmp/hostname_fqdn
ssh some_user#10.9.11.4 -i ~/.ssh/id_rsa $CMD
And now, on remote side created file /tmp/hostname_fqdn contains hostname of client side instead of hostname of remote side. Is it possible to evaluate part of command (hostname --fqdn) on remote side? How to do it?
ssh some_user#10.9.11.4 -i ~/.ssh/id_rsa hostname --fqdn >> /tmp/hostname_fqdn
or, if the CMD may change at runtime:
CMD="hostname --fqdn" && ssh cloud.luminrobotics.com $CMD >> /tmp/xxx
You cannot, however, keep the redirection of the output (>> filename) be part of the command variable, because the command will be executed on the remote host.
PS: If what you want to do with the output changes at runtime as well, then you need to use a pipe and a separate command variable, e.g.,:
CMD_REMOTE="hostname --fqdn"
CMD_LOCAL="tee /tmp/hostname_fqdn"
ssh cloud.luminrobotics.com $CMD | $CMD_LOCAL
First,
CMD=echo $(hostname --fqdn) >> /tmp/hostname_fqdn
will likely do nothing like what you expect.
CMD=echo will be pasred as setting echo as the value of $CMD, and then the return from the hostname subshell we be executed, and likely fail, creating an empty file /tmp/hostname_fqdn
ssh on the other hand is pretty flexible. You could use
ssh some_user#10.9.11.4 -i ~/.ssh/id_rsa 'hostname --fqdn >> /tmp/hostname_fqdn'
if you want the remote hostname saved to a file on the remote host, or
ssh some_user#10.9.11.4 -i ~/.ssh/id_rsa 'hostname --fqdn' >> /tmp/hostname_fqdn
if you want the remote hostname on the local server, or
hostname --fqdn | ssh some_user#10.9.11.4 -i ~/.ssh/id_rsa 'cat >> /tmp/hostname_fqdn'
if you want the local hostname on the remote server...
You have options. :)

SSH: Self-signed- The authenticity if host cant be established

I get the next message from SSH client every time I try to connect to my server:
The authenticity of host "XXX" can't be established. ECDSA key fingerprint is SHA256:...
Are you sure you want to continue connecting(yes/no/[fingerprint])?
I Understand that this message should only apear my first time connecting, not each and every time.
Why does it happen?
Does it mean that it is a self signed ceetificate?
Have a good day!
There are few things you can try:
Make sure ~/.ssh/known_hosts is writable. Because system will try and add the host key into this file.
Depending on your ssh client, you can set the StrictHostKeyChecking option to no on the command line, and/or send the key to a null known_hosts file. You can also set these options in your config file, either for all hosts or for a given set of IP addresses or host names.
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no
This option is not very secure as it may open up Man in the middle attacks. Please carefully consider before doing this.
https://linuxcommando.blogspot.com/2008/10/how-to-disable-ssh-host-key-checking.html
[NOT SECURE] Another way is to use 'BatchMode' in addition to 'StrictHostKeyChecking'. This way, your script will accept a new hostname and write it to the known_hosts file, but won't require yes/no intervention.
ssh -o BatchMode=yes -o StrictHostKeyChecking=no user#server.example.com "uptime"

answer terminal query and log in ssh automatically

I get no response running
workssh() { sshpass -p "password" ssh user#$1 ;}
It was erroring out due to the host being unknown:
cchilders: [master]$ ssh user#host
The authenticity of host 'host (10.10.10.10)' can't be established.
RSA key fingerprint is aa:aa:aa:aa:aa:aa:aa:aa.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'host, 10.10.10.10' (RSA) to the list of known hosts.
user#host's password:
Last login: Tue Mar 15 11:16:03 2016 from 10.55.55.55
If I log in by hand once and say yes, the function workssh now works. How can I make this command work the first time even iworkssh() { sshpass -p "password" ssh user#$1 ;}f host is unknown? thank you
First of: what #chepner said in the comments; I don't recommend doing this for security reasons. But here's your answer, anyway:
workssh() { if $(grep -vq $1 ~/.ssh/known_hosts); then ssh-keyscan $1 >> ~/.ssh/known_hosts; fi ; sshpass -p "password" ssh user#$1 ;}
Notes: for this to work you will need to have HashKnownHosts set to no in man ssh_config, which, in itself, is considered a security risk.
You can go down the hole as the other answer propose, but if you want to be insecure, there are more simple ways to do that:
workssh() { sshpass -p "password" ssh -oUserKnownHostsFile=/dev/null -oStrictHostKeyChecking=no user#$1 ;}
which will do basically the same. But once more, it is not recommended, because the host checking is the only mechanism protecting you from the Man In the Middle attack, as you have probably already noticed in your testing.

How to pass the password to su/sudo/ssh without overriding the TTY?

I'm writing a C Shell program that will be doing su or sudo or ssh. They all want their passwords in console input (the TTY) rather than stdin or the command line.
Does anybody know a solution?
Setting up password-less sudo is not an option.
expect could be an option, but it's not present on my stripped-down system.
For sudo there is a -S option for accepting the password from standard input. Here is the man entry:
-S The -S (stdin) option causes sudo to read the password from
the standard input instead of the terminal device.
This will allow you to run a command like:
echo myPassword | sudo -S ls /tmp
As for ssh, I have made many attempts to automate/script it's usage with no success. There doesn't seem to be any build-in way to pass the password into the command without prompting. As others have mentioned, the "expect" utility seems like it is aimed at addressing this dilemma but ultimately, setting up the correct private-key authorization is the correct way to go when attempting to automate this.
I wrote some Applescript which prompts for a password via a dialog box and then builds a custom bash command, like this:
echo <password> | sudo -S <command>
I'm not sure if this helps.
It'd be nice if sudo accepted a pre-encrypted password, so I could encrypt it within my script and not worry about echoing clear text passwords around. However this works for me and my situation.
For ssh you can use sshpass: sshpass -p yourpassphrase ssh user#host.
You just need to download sshpass first :)
$ apt-get install sshpass
$ sshpass -p 'password' ssh username#server
For sudo you can do this too:
sudo -S <<< "password" command
I've got:
ssh user#host bash -c "echo mypass | sudo -S mycommand"
Works for me.
The usual solution to this problem is setuiding a helper app that performs the task requiring superuser access:
http://en.wikipedia.org/wiki/Setuid
Sudo is not meant to be used offline.
Later edit: SSH can be used with private-public key authentication. If the private key does not have a passphrase, ssh can be used without prompting for a password.
Maybe you can use an expect command?:
expect -c 'spawn ssh root#your-domain.com;expect password;send "your-password\n";interact
That command gives the password automatically.
This can be done by setting up public/private keys on the target hosts you will be connecting to.
The first step would be to generate an ssh key for the user running the script on the local host, by executing:
ssh-keygen
Enter file in which to save the key (/home/myuser/.ssh/id_rsa): <Hit enter for default>
Overwrite (y/n)? y
Then enter a blank password. After that, copy your ssh key onto the target host which you will be connecting to.
ssh-copy-id <remote_user>#<other_host>
remote_user#other_host's password: <Enter remote user's password here>
After registering the ssh keys, you would be able to perform a silent ssh remote_user#other_host from you local host.
When there's no better choice (as suggested by others), then man socat can help:
(sleep 5; echo PASSWORD; sleep 5; echo ls; sleep 1) |
socat - EXEC:'ssh -l user server',pty,setsid,ctty
EXEC’utes an ssh session to server. Uses a pty for communication
between socat and ssh, makes it ssh’s controlling tty (ctty),
and makes this pty the owner of a new process group (setsid), so
ssh accepts the password from socat.
All of the pty,setsid,ctty complexity is necessary and, while you might not need to sleep as long, you will need to sleep. The echo=0 option is worth a look too, as is passing the remote command on ssh's command line.
Take a look at expect linux utility.
It allows you to send output to stdio based on simple pattern matching on stdin.
ssh -t -t me#myserver.io << EOF
echo SOMEPASSWORD | sudo -S do something
sudo do something else
exit
EOF
Set SSH up for Public Key Authentication, with no pasphrase on the Key. Loads of guides on the net. You won't need a password to login then. You can then limit connections for a key based on client hostname. Provides reasonable security and is great for automated logins.
echo <password> | su -c <command> <user>
This is working.
a better sshpass alternative is: passh
https://github.com/clarkwang/passh
Login to a remote server
$ passh -p password ssh user#host
Run a command on remote server
$ passh -p password ssh user#host date
other methods to pass the password
-p The password (Default: `password')
-p env: Read password from env var
-p file: Read password from file
here I explained why it is better than sshpass, and other solutions.
You can also pass various parameters as follows:
echo password | echo y | sudo -S pacman -Syu
(Although that's a bad idea, it's just an example)
I had the same problem. dialog script to create directory on remote pc.
dialog with ssh is easy. I use sshpass (previously installed).
dialog --inputbox "Enter IP" 8 78 2> /tmp/ip
IP=$(cat /tmp/ip)
dialog --inputbox "Please enter username" 8 78 2> /tmp/user
US=$(cat /tmp/user)
dialog --passwordbox "enter password for \"$US\" 8 78 2> /tmp/pass
PASSWORD = $(cat /tmp/pass)
sshpass -p "$PASSWORD" ssh $US#$IP mkdir -p /home/$US/TARGET-FOLDER
rm /tmp/ip
rm /tmp/user
rm /tmp/pass
greetings from germany
titus
Building on #Jahid's answer, this worked for me on macOS 10.13:
ssh <remote_username>#<remote_server> sudo -S <<< <remote_password> cat /etc/sudoers
I once had a use case where I needed to run Sudo and ssh in the same command without stdin specifying all the variables needed.
This is the command I used
echo sudopassword | sudo -S -u username sshpass -p extsshpassword ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no username#ipaddress " CMD on external machine"
Breaking that command into pieces!
This will allow you to run commands through your machine using Superuser:
echo password | sudo -S -u username
This will allow you to pass ssh password and execute commands on external machines:
sshpass -p sshpassword ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no username#ipaddress " CMD on external machine"
make sure you install the sudo and openssh packages on your machine.
One way would be to use read -s option .. this way the password characters are not echoed back to the screen. I wrote a small script for some use cases and you can see it in my blog:
http://www.datauniv.com/blogs/2013/02/21/a-quick-little-expect-script/
USE:
echo password | sudo command
Example:
echo password | sudo apt-get update; whoami
Hope It Helps..
You can provide password as parameter to expect script.
su -c "Command" < "Password"
Hope it is helpful.

How to pass password to scp?

I know it is not recommended, but is it at all possible to pass the user's password to scp?
I'd like to copy a file via scp as part of a batch job and the receiving server does, of course, need a password and, no, I cannot easily change that to key-based authentication.
Use sshpass:
sshpass -p "password" scp -r user#example.com:/some/remote/path /some/local/path
or so the password does not show in the bash history
sshpass -f "/path/to/passwordfile" scp -r user#example.com:/some/remote/path /some/local/path
The above copies contents of path from the remote host to your local.
Install :
ubuntu/debian
apt install sshpass
centos/fedora
yum install sshpass
mac w/ macports
port install sshpass
mac w/ brew
brew install https://raw.githubusercontent.com/kadwanev/bigboybrew/master/Library/Formula/sshpass.rb
just generate a ssh key like:
ssh-keygen -t rsa -C "your_email#youremail.com"
copy the content of ~/.ssh/id_rsa.pub
and lastly add it to the remote machines ~/.ssh/authorized_keys
make sure remote machine have the permissions 0700 for ~./ssh folder and 0600 for ~/.ssh/authorized_keys
If you are connecting to the server from Windows, the Putty version of scp ("pscp") lets you pass the password with the -pw parameter.
This is mentioned in the documentation here.
curl can be used as a alternative to scp to copy a file and it supports a password on the commandline.
curl --insecure --user username:password -T /path/to/sourcefile sftp://desthost/path/
You can script it with a tool like expect (there are handy bindings too, like Pexpect for Python).
You can use the 'expect' script on unix/terminal
For example create 'test.exp' :
#!/usr/bin/expect
spawn scp /usr/bin/file.txt root#<ServerLocation>:/home
set pass "Your_Password"
expect {
password: {send "$pass\r"; exp_continue}
}
run the script
expect test.exp
I hope that helps.
You may use ssh-copy-id to add ssh key:
$which ssh-copy-id #check whether it exists
If exists:
ssh-copy-id "user#remote-system"
Here is an example of how you do it with expect tool:
sub copyover {
$scp = Expect->spawn("/usr/bin/scp ${srcpath}/$file $who:${destpath}/$file");
$scp->expect(30,"ssword: ") || die "Never got password prompt from $dest:$!\n";
print $scp 'password' . "\n";
$scp->expect(30,"-re",'$\s') || die "Never got prompt from parent system:$!\n";
$scp->soft_close();
return;
}
Nobody mentioned it, but Putty scp (pscp) has a -pw option for password.
Documentation can be found here: https://the.earth.li/~sgtatham/putty/0.67/htmldoc/Chapter5.html#pscp
Once you set up ssh-keygen as explained above, you can do
scp -i ~/.ssh/id_rsa /local/path/to/file remote#ip.com:/path/in/remote/server/
If you want to lessen typing each time, you can modify your .bash_profile file and put
alias remote_scp='scp -i ~/.ssh/id_rsa /local/path/to/file remote#ip.com:/path/in/remote/server/
Then from your terminal do source ~/.bash_profile. Afterwards if you type remote_scp in your terminal it should run the scp command without password.
Here's a poor man's Linux/Python/Expect-like example based on this blog post: Upgrading simple shells to fully interactive
TTYs. I needed this for old machines where I can't install Expect or add modules to Python.
Code:
(
echo 'scp jmudd#mysite.com:./install.sh .'
sleep 5
echo 'scp-passwd'
sleep 5
echo 'exit'
) |
python -c 'import pty; pty.spawn("/usr/bin/bash")'
Output:
scp jmudd#mysite.com:install.sh .
bash-4.2$ scp jmudd#mysite.com:install.sh .
Password:
install.sh 100% 15KB 236.2KB/s 00:00
bash-4.2$ exit
exit
Make sure password authentication is enabled on the target server. If it runs Ubuntu, then open /etc/ssh/sshd_config on the server, find lines PasswordAuthentication=no and comment all them out (put # at the start of the line), save the file and run sudo systemctl restart ssh to apply the configuration. If there is no such line then you're done.
Add -o PreferredAuthentications="password" to your scp command, e.g.:
scp -o PreferredAuthentications="password" /path/to/file user#server:/destination/directory
make sure you have "expect" tool before, if not, do it
# apt-get install expect
create the a script file with following content. (# vi /root/scriptfile)
spawn scp /path_from/file_name user_name_here#to_host_name:/path_to
expect "password:"
send put_password_here\n;
interact
execute the script file with "expect" tool
# expect /root/scriptfile
copy files from one server to other server ( on scripts)
Install putty on ubuntu or other Linux machines. putty comes with pscp. we can copy files with pscp.
apt-get update
apt-get install putty
echo n | pscp -pw "Password#1234" -r user_name#source_server_IP:/copy_file_path/files /path_to_copy/files
For more options see pscp help.
Using SCP non interactively from Windows:
Install the community Edition of netcmdlets
Import Module
Use Send-PowerShellServerFile -AuthMode password -User MyUser -Password not-secure -Server YourServer -LocalFile C:\downloads\test.txt -RemoteFile C:\temp\test.txt for sending File with non-interactive password
In case if you observe a strict host key check error then use -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null options.
The complete example is as follows
sshpass -p "password" scp -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null root#domain-name.com:/tmp/from/psoutput /tmp/to/psoutput
You can use below steps. This works for me!
Step1-
create a normal file suppose "fileWithScpPassword" which contains the ssh password for the destination server.
Step2- use sshpaas -f followed by password file name and then normal scp command.
sshpass -f "fileWithScpPassword" scp /filePathToUpload user#ip:/destinationPath/
One easy way I do this:
Use the same scp cmd as you use with ssh keys i.e
scp -C -i <path_to opens sshkey> <'local file_path'> user#<ip_address_VM>: <'remote file_path’>
for transferring file from local to remote
but instead of providing the correct <path_to_opensshkey>, use some garbage path. Due to wrong key path you will be asked for password instead and you can simply pass the password now to get the work done!
An alternative would be add the public half of the user's key to the authorized-keys file on the target system. On the system you are initiating the transfer from, you can run an ssh-agent daemon and add the private half of the key to the agent. The batch job can then be configured to use the agent to get the private key, rather than prompting for the key's password.
This should be do-able on either a UNIX/Linux system or on Windows platform using pageant and pscp.
All the solutions mentioned above can work only if you the app installed or you should have the admin rights to install except or sshpass.
I found this very useful link to simply start the scp in Background.
$ nohup scp file_to_copy user#server:/path/to/copy/the/file > nohup.out 2>&1
https://charmyin.github.io/scp/2014/10/07/run-scp-in-background/
I found this really helpful answer here.
rsync -r -v --progress -e ssh user#remote-system:/address/to/remote/file /home/user/
Not only you can pass there the password, but also it will show the progress bar when copying. Really awesome.

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