This question already has answers here:
How can I force ssh to accept a new host fingerprint from the command line?
(9 answers)
Closed 3 years ago.
I have a shell script which is performing some renaming and archiving steps. I have added sftp commands to copy multiple files. But when i try to login to the remote machine thru putty it asks for confirmation like Are you sure you want to continue connecting (yes/no)? . I need to enter yes. but since this is being done thru the script am not sure how to do it. below is the script i am using
cd <File Source Location>
sftp user1#remoteserver
sftp> cd <target location to be copied>
sftp> mput *.gz
quit
how to i pass yes in the above code after sftp user1#remoteserver is executed.
Any help is much appreciated.
I think that you are trying to solve the wrong problem.
sftp asks you for confirmation because it does not know the key of the host yet. Therefore you need to add it to you known_hosts file like this
ssh-keyscan -H remoteserver >> ~/.ssh/known_hosts
I recommend using scp command instead of sftp as it will do all you want in one step.
scp somewhere/*.gz user1#remoteserver:somewhere/else
If for some reason you don't want to do it. You may consider a very insecure command
sftp -o StrictHostKeyChecking=no user1#remoteserver
By using the command above you are vulnerable to Man in the Middle attack, you've been warned.
Related
This question already has answers here:
Shell script: Run function from script over ssh
(3 answers)
Closed 5 years ago.
Am trying to login into a remote server, and I want to function to be executed on remote server. Can I send the function name including in ssh command.
Of course you can. the below is the appropriate syntax for it. You can run one or more commands separated by semicolon.
ssh -n -l yourusername yourremoteserver "pwd; hostname; netstat -tupln | tail -5"
Let me know if this works for you.
Note - Be aware that in will ask for your password. If you are planning to use this inside a script, you should copy your keys to the remote server you are trying to run the command on, and only then it will authenticate using the keys instead of prompting for your password. Copy the same is a straight forward process, really simple, you can see the steps here:
https://askubuntu.com/questions/4830/easiest-way-to-copy-ssh-keys-to-another-machine
This question already has answers here:
How to run the sftp command with a password from Bash script?
(12 answers)
Closed 8 years ago.
I need to make a shell script that will transfer files to a remote server however, the account given to me has no shell mainly because they want to restrict the access to sftp only. I already have a shell script my only problem is that I cannot automate it. The script stops on the password prompt. I read on most of the passwordless sftp tutorials that I need to generate a keypair but like i've said I cannot do this as the remote account has no shell access. What are the alternatives for passwordless sftp considering an account without shell? The remote server has no 'expect' installed.
Thank you very much.
EDIT: Please also note that I cannot install anything in the local server. I MAY be able to do something on the remote server but not on the local.
On Debian and Ubuntu (maybe other systems also) you can use sshpass
apt-get install sshpass
sshpass -p 'YourPassword' ssh user#host
OR
sshpass -p 'YourPassword' sftp user#host
But the you will have your password printed in your bash_history..
So you might want to pass the password from a file or an environment-variable.
Greets, Eric
I want to install a software library (SWIG) on a list of computers (Jenkins nodes). I'm using the following script to automate this somewhat:
NODES="10.8.255.70 10.8.255.85 10.8.255.88 10.8.255.86 10.8.255.65 10.8.255.64 10.8.255.97 10.8.255.69"
for node in $NODES; do
scp InstallSWIG.sh root#$node:/root/InstallSWIG.sh
ssh root#$node sh InstallSWIG.sh
done
This way it's automated, except for the password request that occur for both the scp and ssh commands.
Is there a way to enter the passwords programmatically?
Security is not an issue. I’m looking for solutions that don’t involve SSH keys.
Here’s an expect example that sshs in to Stripe’s Capture The Flag server and enters the password automatically.
expect <<< 'spawn ssh level01#ctf.stri.pe; expect "password:"; send "e9gx26YEb2\r";'
With SSH the right way to do it is to use keys instead.
# ssh-keygen
and then copy the *~/.ssh/id_rsa.pub* file to the remote machine (root#$node) into the remote user's .ssh/authorized_keys file.
You can perform the task using empty, a small utility from sourceforge. It's similar to expect but probably more convenient in this case. Once you have installed it, your first scp will be accomplished by following two commands:
./empty -f scp InstallSWIG.sh root#$node:/root/InstallSWIG.sh
echo YOUR_SECRET_PASSWORD | ./empty -s -c
The first one starts your command in the background, tricking it into thinking it's running in interactive mode on a terminal. The other one sends it data from stdin. Of course, putting your password anywhere on command line is risky due to shell history being preserved, users being able to see it in ps results etc. Not secure either, but a bit better thing would be to store the password in a file and redirect the second command's input from that file instead of using echo and a pipe.
After copying to the server, you can run the script in a similar manner:
./empty -f ssh root#$node sh InstallSWIG.sh
echo YOUR_SECRET_PASSWORD | ./empty -s -c
You could look into setting up passwordless ssh keys for that. Establishing Batch Mode Connections between OpenSSH and SSH2 is a starting point, you'll find lots of information on this topic on the web.
Wes' answer is the correct one but if you're keen on something dirty and slow, you can use expect to automate this.
This question already has answers here:
How to run the sftp command with a password from Bash script?
(12 answers)
Closed 7 years ago.
I am trying to write a script to back up a file over SFTP. The problem is, it requires a password, and I see no way to manually specify a password to SFTP. I've heard about requiring no password by using public keys, but that requires being able to ssh into the remote server and modify some configuration files, which I cannot do.
Currently my solution is to use cURL, but that is insecure (uses normal FTP). I also looked at the .netrc file, but that seems to be for FTP instead of SFTP. How do I manually specify a password for sftp?
Lftp allows specifying passwords for both ftp and sftp and does not require public keys at all. Your sh sync script may look like this:
#!/bin/sh
# Define folders
THEFOLDER='/mnt/my/folder'
# List files
THEFILES=`ls -p $THEFOLDER | grep -v "/"`
for file in $THEFILES
do
echo "Processing $file"
lftp -u login,password -e "put $THEFOLDER/$file;quit" theftp/sub/folder
done
cURL can support sftp, as documented by the manual:
USING PASSWORDS
FTP
To ftp files using name+passwd, include them in the URL like:
curl ftp://name:passwd#machine.domain:port/full/path/to/file
or specify them with the -u flag like
curl -u name:passwd ftp://machine.domain:port/full/path/to/file
FTPS
It is just like for FTP, but you may also want to specify and use
SSL-specific options for certificates etc.
Note that using FTPS:// as prefix is the "implicit" way as described in the
standards while the recommended "explicit" way is done by using FTP:// and
the --ftp-ssl option.
SFTP / SCP
This is similar to FTP, but you can specify a private key to use instead of
a password. Note that the private key may itself be protected by a password
that is unrelated to the login password of the remote system. If you
provide a private key file you must also provide a public key file.
You might also want to consider using python (the paramiko module), as it can quickly be called from the shell.
Install the Module
pip install paramiko
Example FTP Upload Script
import paramiko
username = 'my_username'
password = 'my_password'
transport = paramiko.Transport((server, 22))
transport.connect(username=username, password=password)
sftp = paramiko.SFTPClient.from_transport(transport)
local_filename = '/tmp/filename'
remote_filename = 'MyFiles/temp.txt'
sftp.put( local_filename, remote_filename )
Bash program to wait for sftp to ask for a password then send it along:
#!/bin/bash
expect -c "
spawn sftp username#your_host
expect \"assword\"
send \"your_password_here\r\"
interact "
Put that in a file called sftp_autologin.sh. The \r sends an to sftp to execute the command. I don't include the 'p' in password because on some systems it's uppercase, others lowercase. expect spawns the sftp command. Waits for the string 'assword' to be seen and sends a command. Then ends.
To get this to work:
Install expect, I'm using 5.44.1.15
Make sure you can sftp to your box in interactive mode and supply a password.
Make sure this bash script has executable permissions.
Then run it:
chmod +x sftp_autologin.sh
./sftp_autologin.sh
It should drop you into the sftp commandline without prompting you for a password.
Is it insecure?
It's about the most unsecure command you can run. It exposes the password to the commandline history, to anyone else who can read 'ps' output, and basically defeats the entire purpose of passwords all together.
But hey what's another log on the fraud fire, it's only about 250b dollars in victim losses per year. Lets go for 500b.
This automatically runs some commands with the sftp shell and exits automatically when done:
#!/bin/bash
expect -c "
spawn sftp myuser#myserver.com
expect \"assword\"
send \"yourpassword\r\"
expect \"sftp\"
send \"get your_directory/yourfilename.txt\r\"
expect \"sftp\"
send \"exit\r\"
interact "
In order to use public keys you do not need to modify any "configuration files". You merely need to leave a copy of your public key in a place where ssh knows to look (normally ~/.ssh/authorized_keys). You can do this with sftp. If you haven't established any authorized_keys file on the server, you can simply put your id_rsa.pub file in its place.
You can't specify a password to ssh / scp or sftp from the command line. The only way to connect without prompting for a password is to use public key authentication.
You say that you can't ssh to the server to modify configuration files but if you can sftp to the server you can probably upload your public key.
Your public key just has to go under the .ssh directory in your home directory.
I need to transfer a log file to a remote host using sftp from a Linux host. I have been provided credentials for the same from my operations group. However, since I don't have control over other host, I cannot generate and share RSA keys with the other host.
So is there a way to run the sftp command (with the username/password provided) from inside the Bash script through a cron job?
I found a similar Stack Overflow question, Specify password to sftp in a Bash script, but there was no satisfactory answer to my problem.
You have a few options other than using public key authentication:
Use keychain
Use sshpass (less secured but probably that meets your requirement)
Use expect (least secured and more coding needed)
If you decide to give sshpass a chance here is a working script snippet to do so:
export SSHPASS=your-password-here
sshpass -e sftp -oBatchMode=no -b - sftp-user#remote-host << !
cd incoming
put your-log-file.log
bye
!
Another way would be to use lftp:
lftp sftp://user:password#host -e "put local-file.name; bye"
The disadvantage of this method is that other users on the computer can read the password from tools like ps and that the password can become part of your shell history.
A more secure alternative which is available since LFTP 4.5.0 is setting the LFTP_PASSWORD environment variable and executing lftp with --env-password. Here's a full example:
export LFTP_PASSWORD="just_an_example"
lftp --env-password sftp://user#host -e "put local-file.name; bye"
# Destroy password after use
export LFTP_PASSWORD=""
LFTP also includes a cool mirroring feature (can include delete after confirmed transfer --Remove-source-files):
lftp -e 'mirror -R /local/log/path/ /remote/path/' --env-password -u user sftp.foo.com
EXPECT is a great program to use.
On Ubuntu install it with:
sudo apt-get install expect
On a CentOS Machine install it with:
yum install expect
Lets say you want to make a connection to a sftp server and then upload a local file from your local machine to the remote sftp server
#!/usr/bin/expect
spawn sftp username#hostname.com
expect "password:"
send "yourpasswordhere\n"
expect "sftp>"
send "cd logdirectory\n"
expect "sftp>"
send "put /var/log/file.log\n"
expect "sftp>"
send "exit\n"
interact
This opens a sftp connection with your password to the server.
Then it goes to the directory where you want to upload your file, in this case "logdirectory"
This uploads a log file from the local directory found at /var/log/ with the files name being file.log to the "logdirectory" on the remote server
You can use lftp interactively in a shell script so the password not saved in .bash_history or similar by doing the following:
vi test_script.sh
Add the following to your file:
#!/bin/sh
HOST=<yourhostname>
USER=<someusername>
PASSWD=<yourpasswd>
cd <base directory for your put file>
lftp<<END_SCRIPT
open sftp://$HOST
user $USER $PASSWD
put local-file.name
bye
END_SCRIPT
And write/quit the vi editor after you edit the host, user, pass, and directory for your put file typing :wq .Then make your script executable chmod +x test_script.sh and execute it ./test_script.sh.
I was recently asked to switch over from ftp to sftp, in order to secure the file transmission between servers. We are using Tectia SSH package, which has an option --password to pass the password on the command line.
example : sftp --password="password" "userid"#"servername"
Batch example :
(
echo "
ascii
cd pub
lcd dir_name
put filename
close
quit
"
) | sftp --password="password" "userid"#"servername"
I thought I should share this information, since I was looking at various websites, before running the help command (sftp -h), and was i surprised to see the password option.
You can override by enabling Password less authentication. But you should install keys (pub, priv) before going for that.
Execute the following commands at local server.
Local $> ssh-keygen -t rsa
Press ENTER for all options prompted. No values need to be typed.
Local $> cd .ssh
Local $> scp .ssh/id_rsa.pub user#targetmachine:
Prompts for pwd$> ENTERPASSWORD
Connect to remote server using the following command
Local $> ssh user#targetmachine
Prompts for pwd$> ENTERPASSWORD
Execute the following commands at remote server
Remote $> mkdir .ssh
Remote $> chmod 700 .ssh
Remote $> cat id_rsa.pub >> .ssh/authorized_keys
Remote $> chmod 600 .ssh/authorized_keys
Remote $> exit
Execute the following command at local server to test password-less authentication.
It should be connected without password.
$> ssh user#targetmachine
The easiest way I found to accomplish this, without installing any third-party library like Expect, SSHPASS...etc, is by using a combination of CURL, and SFTP. Those two are almost in every Linux machine.
This is the command you should execute, after changing the values.
curl -k "sftp://SERVER_IP:SERVER_PORT/FULL_PATH_OF_THE_FILE" --user "SERVER_USER:SERVER_PASSOWRD" -o "THE_NAME_OF_THE_FILE_AFTER_DOWNLOADING_IT"
Example:
curl -k "sftp://10.10.10.10:77/home/admin/test.txt" --user "admin:123456" -o "test.txt"
Explanation:
We are connecting to the server 10.10.10.10:77 using the username admin and password 123456, to move the file /home/admin/test.txt from that server to the server you are using currently to execute the above command.
Combine sshpass with a locked-down credentials file and, in practice, it's as secure as anything - if you've got root on the box to read the credentials file, all bets are off anyway.
Bash program to wait for sftp to ask for a password then send it along:
#!/bin/bash
expect -c "
spawn sftp username#your_host
expect \"Password\"
send \"your_password_here\r\"
interact "
You may need to install expect, change the wording of 'Password' to lowercase 'p' to match what your prompt receives. The problems here is that it exposes your password in plain text in the file as well as in the command history. Which nearly defeats the purpose of having a password in the first place.
You can use sshpass for it. Below are the steps
Install sshpass For Ubuntu - sudo apt-get install sshpass
Add the Remote IP to your known-host file if it is first time
For Ubuntu -> ssh user#IP -> enter 'yes'
give a combined command of scp and sshpass for it.
Below is a sample code for war coping to remote tomcat
sshpass -p '#Password_For_remote_machine' scp /home/ubuntu/latest_build/abc.war #user##RemoteIP:/var/lib/tomcat7/webapps
You can use a Python script with scp and os library to make a system call.
ssh-keygen -t rsa -b 2048 (local machine)
ssh-copy-id user#remote_server_address
create a Python script like:
import os
cmd = 'scp user#remote_server_address:remote_file_path local_file_path'
os.system(cmd)
create a rule in crontab to automate your script
done
A few people have mentioned sshpass but not many clear coding examples...
This is how we are doing it with bash scripts for rsync backups:
sshpass -p "${RSYNC_PASSWORD}" sftp "${RSYNC_USER}"#"${RSYNC_REMOTE_HOST}"
Keep in mind you will have to sudo apt install sshpass before this works properly.