152

I have an Ubuntu server to which I am connecting using SSH.

I need to upload files from my machine into /var/www/ on the server, the files in /var/www/ are owned by root.

Using PuTTY, after I log in, I have to type sudo su and my password first in order to be able to modify files in /var/www/.

But when I am copying files using WinSCP , I can't create create/modify files in /var/www/, because the user I'm connecting with does not have permissions on files in /var/www/ and I can't say sudo su as I do in case of an ssh session.

Do you know how i could deal with this ?

If I was working on my local machine, I would call gksudo nautilus but in this case I only have terminal access to the machine.

  • This seems more like a question for your virtual server provider, or for the putty or winscp developers. – dobey Oct 29 '12 at 21:17
  • 6
    @dobey you obviusly wrong , it is about ubuntu privileges ! – Dimitris Sapikas Oct 30 '12 at 10:14
  • 6
    Why is this closed? This is a perfectly valid question about copying files with scp - every web developer is familiar with this situation – Sergey Oct 30 '12 at 22:02
  • Copying protected files between servers in one line? should help. – Gilles Oct 30 '12 at 23:04
  • I have a similar problem. I create a file (HTML in this case) on Windows computer and try to copy it with WinSCP to /var/www/html/website folder. And it says that there is a permission problem. Because I can copy to my /home folder I copied the file in two steps, but it isn't very convenient :-) I tried with adding my user to www-data group, but it didn't help. Any idea why adding to user to www-data still don't allow user to copy a file to folder which is owned by www-data group? – JanezKranjski Feb 21 '18 at 4:55

10 Answers 10

113

You're right, there is no sudo when working with scp. A workaround is to use scp to upload files to a directory where your user has permissions to create files, then log in via ssh and use sudo to move/copy files to their final destination.

scp -r folder/ user@server.tld:/some/folder/you/dont/need/sudo
ssh user@server.tld
 $ sudo mv /some/folder /some/folder/requiring/perms 
# YOU MAY NEED TO CHANGE THE OWNER like:
# sudo chown -R user:user folder

Another solution would be to change permissions/ownership of the directories you uploading the files to, so your non-privileged user is able to write to those directories.

Generally, working in the root account should be an exception, not a rule - the way you phrasing your question makes me think maybe you're abusing it a bit, which in turn leads to problems with permissions - under normal circumstances you don't need super-admin privileges to access your own files.

Technically, you can configure Ubuntu to allow remote login directly as root, but this feature is disabled for a reason, so I would strongly advice you against doing that.

  • i didn't get the first solution , could you please be a litle more spesific ? – Dimitris Sapikas Oct 30 '12 at 9:42
  • Whe i say my own files i mean /var/www , i am using my vps as web server .... on my own folder i have full access – Dimitris Sapikas Oct 30 '12 at 9:44
  • 7
    Re. the first solution. 1. scp -R mysite dimitris@myserver.com:/home/dimitris/ 2. ssh dimitris@myserver.com 3. sudo mv ~/mysite /var/www - it's a 2-step process, first you scp the files to your home dir, then you log in via ssh and copy/move the files to where they should be – Sergey Oct 30 '12 at 21:58
31

Another method is to copy using tar + ssh instead of scp:

tar -c -C ./my/local/dir \
  | ssh dimitris@myserver.com "sudo tar -x --no-same-owner -C /var/www"
  • 2
    This is the best way to do it. – mttdbrd Mar 30 '15 at 20:31
  • 2
    I can't get this method to work successfully. As written I get sudo: sorry, you must have a tty to run sudo. If I add "-t" to allocate a TTY then I get Pseudo-terminal will not be allocated because stdin is not a terminal.. I can't see this working without passwordless sudo. – IBBoard Oct 26 '15 at 16:35
  • 1
    @IBBoard : try the solution here using ssh -t: ssh -t dimitris@myserver.com "sudo tar -x --no-same-owner -C /var/www" – Alexander Bird Aug 18 '16 at 15:21
  • 2
    @AlexanderBird While that works in many cases, I'm not sure it works here because we're trying to pipe a tarball over the SSH connection. See serverfault.com/questions/14389/… – IBBoard Aug 19 '16 at 19:36
  • This is what finally worked for me. You don't have permissions to a remote file that you want to copy to local, do a sudo tar, archive it, change permissions using chmod and chown, and then copy it to local. Especially if it's a directory. – forumulator Aug 9 '18 at 9:07
24

You can also use ansible to accomplish this.

Copy to remote host using ansible's copy module:

ansible -i HOST, -b -m copy -a "src=SRC_FILEPATH dest=DEST_FILEPATH" all

Fetch from remote host using ansible's fetch module:

ansible -i HOST, -b -m fetch -a "src=SRC_FILEPATH dest=DEST_FILEPATH flat=yes" all

NOTE:

  • The comma in the -i HOST, syntax is not a typo. It is the way to use ansible without needing an inventory file.
  • -b causes the actions on the server to be done as root. -b expands to --become, and the default --become-user is root, with the default --become-method being sudo.
  • flat=yes copies just the file, doesn't copy whole remote path leading to the file
  • Using wildcards in the file paths isn't supported by these ansible modules.
  • Copying a directory is supported by the copy module, but not by the fetch module.

Specific Invocation for this Question

Here's an example that is specific and fully specified, assuming the directory on your local host containing the files to be distributed is sourcedir, and that the remote target's hostname is hostname:

cd sourcedir && \
ansible \
   --inventory-file hostname, \ 
   --become \
   --become-method sudo \
   --become-user root \
   --module-name copy \
   --args "src=. dest=/var/www/" \
   all

With the concise invocation being:

cd sourcedir && \
ansible -i hostname, -b -m copy -a "src=. dest=/var/www/" all

P.S., I realize that saying "just install this fabulous tool" is kind of a tone-deaf answer. But I've found ansible to be super useful for administering remote servers, so installing it will surely bring you other benefits beyond deploying files.

  • I like the this answer but I recommend you direct it at the asked question versus more generalized commentary before upvote. something like ansible -i "hostname," all -u user --become -m copy -a ... – Mike D Feb 16 '16 at 19:30
  • @MikeD: how do the above changes look? – erik.weathers Feb 19 '16 at 3:08
  • 1
    Would something like -i 'host,' be valid syntax? I think it's easy to lose punctuation like that when reading a command. (For the reader I mean, if not the shell.) – mwfearnley Jun 10 '16 at 15:37
  • 1
    @mwfearnley: sure, the shell will treat -i 'host,' and same as -i host, or -i "host,". In general I prefer to keep these invocations as short as possible to keep them from being daunting, but you should feel free to make it as verbose and explicit as you think is needed for clarity. – erik.weathers Jun 15 '16 at 3:00
  • 2
    Way to go thinking outside the box! Great use of Ansible – jonatan Sep 16 '18 at 9:19
13

Quick way

From server to local machine:

ssh user@server "sudo cat /etc/dir/file" > /home/user/file

From local machine to server:

cat /home/user/file | ssh user@server "sudo tee -a /etc/dir/file"
  • 2
    This answer is underrated. It's simple, clean, reads or writes a root file with a single atomic operation, and requires nothing that's not already guaranteed to be there if you're using scp. Main drawback is that it does not copy permissions. If you want that, the tar solution is better. This is a powerful technique, particularly if combined with xargs/bash magic to traverse paths.. – markgo2k May 16 '18 at 18:12
  • I think the question was about uploading a file from local to remote and not vice versa – Korayem Dec 19 '18 at 6:53
12

When you run sudo su, any files you create will be owned by root, but it is not possible by default to directly log in as root with ssh or scp. It is also not possible to use sudo with scp, so the files are not usable. Fix this by claiming ownership over your files:

Assuming your user name was dimitri, you could use this command.

sudo chown -R dimitri:dimitri /home/dimitri

From then on, as mentioned in other answers, the "Ubuntu" way is to use sudo, and not root logins. It is a useful paradigm, with great security advantages.

  • i am using this solution any way , but what if i could get full access to my own file system , i don't want to type sudo chow ... for every single directory :S – Dimitris Sapikas Oct 30 '12 at 9:47
  • 2
    Changing ownership of all system files to the user for passing convenience is highly discouraged. It allows any userspace bug you might encounter to severely compromise the security of your system. It is much better to change the ownership of the files that you need to change or update by SCP, but to leave everything else owned by root (like it is supposed to be). That said, the -R in chown tells it to change the ownership of that directory, and all children files and directories recursively... so you can do anything you like. – trognanders Oct 30 '12 at 17:48
  • hmm .... that seems working fine , thank you ! sorry i can't upvote (system does not allow me to do ...) – Dimitris Sapikas Oct 30 '12 at 19:05
8

May be the best way is to use rsync (Cygwin/cwRsync in Windows) over SSH?

For example, to upload files with owner www-data:

rsync -a --rsync-path="sudo -u www-data rsync" path_to_local_data/ login@srv01.example.com:/var/www

In your case, if you need root privileges, command will be like this:

rsync -a --rsync-path="sudo rsync" path_to_local_data/ login@srv01.example.com:/var/www

See: scp to remote server with sudo.

5

If you use the OpenSSH tools instead of PuTTY, you can accomplish this by initiating the scp file transfer on the server with sudo. Make sure you have an sshd daemon running on your local machine. With ssh -R you can give the server a way to contact your machine.

On your machine:

ssh -R 11111:localhost:22 REMOTE_USERNAME@SERVERNAME

In addition to logging you in on the server, this will forward every connection made on the server's port 11111 to your machine's port 22: the port your sshd is listening on.

On the server, start the file transfer like this:

cd /var/www/
sudo scp -P 11111 -r LOCAL_USERNAME@localhost:FOLDERNAME .
1

You may use script I've written being inspired by this topic:

touch /tmp/justtest && scpassudo /tmp/justtest remoteuser@ssh.superserver.com:/tmp/

but this requires some crazy stuff (which is btw. automatically done by script)

  1. server which file is being sent to will no longer ask for password while establishing ssh connection to source computer
  2. due to necessarility of lack of sudo prompt on the server, sudo will no longer ask for password on remote machine, for user

Here goes the script:

interface=wlan0
if [[ $# -ge 3 ]]; then interface=$3; fi
thisIP=$(ifconfig | grep $interface -b1 | tail -n1 | egrep -o '[0-9.]{4,}' -m1 | head -n 1)
thisUser=$(whoami)
localFilePath=/tmp/justfortest
destIP=192.168.0.2
destUser=silesia
#dest 
#destFolderOnRemoteMachine=/opt/glassfish/glassfish/
#destFolderOnRemoteMachine=/tmp/

if [[ $# -eq 0 ]]; then 
echo -e "Send file to remote server to locatoin where root permision is needed.\n\tusage: $0 local_filename [username@](ip|host):(remote_folder/|remote_filename) [optionalInterface=wlan0]"
echo -e "Example: \n\ttouch /tmp/justtest &&\n\t $0 /tmp/justtest remoteuser@ssh.superserver.com:/tmp/ "
exit 1
fi

localFilePath=$1

test -e $localFilePath 

destString=$2
usernameAndHost=$(echo $destString | cut -f1 -d':')

if [[ "$usernameAndHost" == *"@"* ]]; then
destUser=$(echo $usernameAndHost | cut -f1 -d'@')
destIP=$(echo $usernameAndHost | cut -f2 -d'@')
else
destIP=$usernameAndHost
destUser=$thisUser
fi

destFolderOnRemoteMachine=$(echo $destString | cut -f2 -d':')

set -e #stop script if there is even single error

echo 'First step: we need to be able to execute scp without any user interaction'
echo 'generating public key on machine, which will receive file'
ssh $destUser@$destIP 'test -e ~/.ssh/id_rsa.pub -a -e ~/.ssh/id_rsa || ssh-keygen -t rsa'
echo 'Done'

echo 'Second step: download public key from remote machine to this machine so this machine allows remote machine (this one receiveing file) to login without asking for password'

key=$(ssh $destUser@$destIP 'cat ~/.ssh/id_rsa.pub')
if ! grep "$key" ~/.ssh/authorized_keys; then
echo $key >> ~/.ssh/authorized_keys
echo 'Added key to authorized hosts'
else
echo "Key already exists in authorized keys"
fi

echo "We will want to execute sudo command remotely, which means turning off asking for password"
echo 'This can be done by this tutorial http://stackoverflow.com/a/10310407/781312'
echo 'This you have to do manually: '
echo -e "execute in new terminal: \n\tssh $destUser:$destIP\nPress enter when ready"
read 
echo 'run there sudo visudo'
read
echo 'change '
echo '    %sudo   ALL=(ALL:ALL) ALL'
echo 'to'
echo '    %sudo   ALL=(ALL:ALL) NOPASSWD: ALL'
echo "After this step you will be done."
read

listOfFiles=$(ssh $destUser@$destIP "sudo ls -a")

if [[ "$listOfFiles" != "" ]]; then 
echo "Sending by executing command, in fact, receiving, file on remote machine"
echo 'Note that this command (due to " instead of '', see man bash | less -p''quotes'') is filled with values from local machine'
echo -e "Executing \n\t""identy=~/.ssh/id_rsa; sudo scp -i \$identy $(whoami)@$thisIP:$(readlink -f $localFilePath) $destFolderOnRemoteMachine"" \non remote machine"
ssh $destUser@$destIP "identy=~/.ssh/id_rsa; sudo scp -i \$identy $(whoami)@$thisIP:$(readlink -f $localFilePath) $destFolderOnRemoteMachine"
ssh $destUser@$destIP "ls ${destFolderOnRemoteMachine%\\\\n}/$(basename $localFilePath)"
if [[ ! "$?" -eq 0 ]]; then echo "errror in validating"; else echo -e "SUCCESS! Successfully sent\n\t$localFilePath \nto \n\t$destString\nFind more at http://arzoxadi.tk"; fi
else
echo "something went wrong with executing sudo on remote host, failure"

fi
ENDOFSCRIPT
) | sudo tee /usr/bin/scpassudo && chmod +x /usr/bin/scpassudo
  • @Braiam yeah, sure, sorry for link, the script is pretty long and that was the reason :) – test30 Nov 22 '13 at 1:42
1

You can combine ssh, sudo and e.g tar to transfer files between servers without being able to log in as root and not having the permission to access the files with your user. This is slightly fiddly, so I've written a script to help this. You can find the script here: https://github.com/sigmunau/sudoscp

or here:

#! /bin/bash
res=0
from=$1
to=$2
shift
shift
files="$@"
if test -z "$from" -o -z "$to" -o -z "$files"
then
    echo "Usage: $0    (file)*"
    echo "example: $0 server1 server2 /usr/bin/myapp"
    exit 1
fi

read -s -p "Enter Password: " sudopassword
echo ""
temp1=$(mktemp)
temp2=$(mktemp)
(echo "$sudopassword";echo "$sudopassword"|ssh $from sudo -S tar c -P -C / $files 2>$temp1)|ssh $to sudo -S tar x -v -P -C / 2>$temp2
sourceres=${PIPESTATUS[0]}
if [ $? -ne 0 -o $sourceres -ne 0 ]
then
    echo "Failure!" >&2
    echo "$from output:" >&2
    cat $temp1 >&2
    echo "" >&2
    echo "$to output:" >&2
    cat $temp2 >&2
    res=1
fi

rm $temp1 $temp2
exit $res
  • Welcome to Ask Ubuntu. Could you please include the script in your answer? I know it is unlikely but if the github repo was ever removed or the url changed then the answer would be void. It is better to include the script directly and leave the github repo as a source. – Michael Lindman Jul 1 '15 at 15:25
0

Here's a modified version of Willie Wheeler's answer that transfers the file(s) via tar but also supports passing a password to sudo on the remote host.

(stty -echo; read passwd; stty echo; echo $passwd; tar -cz foo.*) \
  | ssh remote_host "sudo -S bash -c \"tar -C /var/www/ -xz; echo\""

The little bit of extra magic here is the -S option to sudo. From the sudo man page:

-S, --stdin Write the prompt to the standard error and read the password from the standard input instead of using the terminal device. The password must be followed by a newline character.

Now we actually want the output of tar to be piped into ssh and that redirects the stdin of ssh to the stdout of tar, removing any way to pass the password into sudo from the interactive terminal. (We could use sudo's ASKPASS feature on the remote end but that is another story.) We can get the password into sudo though by capturing it in advance and prepending it to the tar output by performing those operations in a subshell and piping the output of the subshell into ssh. This also has the added advantage of not leaving an environment variable containing our password dangling in our interactive shell.

You'll notice I didn't execute 'read' with the -p option to print a prompt. This is because the password prompt from sudo is conveniently passed back to the stderr of our interactive shell via ssh. You might wonder "how is sudo executing given it is running inside ssh to the right of our pipe?" When we execute multiple commands and pipe the output of one into another, the parent shell (the interactive shell in this case) executes each command in the sequence immediately after executing the previous. As each command behind a pipe is executed the parent shell attaches (redirects) the stdout of the left-hand side to the stdin of the right-hand side. Output then becomes input as it passes through processes. We can see this in action by executing the entire command and backgrounding the process group (Ctrl-z) before typing our password, and then viewing the process tree.

$ (stty -echo; read passwd; stty echo; echo $passwd; tar -cz foo.*) | ssh 
remote_host "sudo -S bash -c \"tar -C /var/www/ -xz; echo\""
[sudo] password for bruce: 
[1]+  Stopped                 ( stty -echo; read passwd; stty echo; echo 
$passwd; tar -cz foo.* ) | ssh remote_host "sudo -S bash -c \"tar -C 
/var/www/ -xz; echo\""

$ pstree -lap $$
bash,7168
  ├─bash,7969
  ├─pstree,7972 -lap 7168
  └─ssh,7970 remote_host sudo -S bash -c "tar -C /var/www/ -xz; echo"`

Our interactive shell is PID 7168, our subshell is PID 7969 and our ssh process is PID 7970.

The only drawback is that read will accept input before sudo has time to send back it's prompt. On a fast connection and fast remote host you won't notice this but you might if either is slow. Any delay will not affect the ability to enter the prompt; it just might appear after you have started typing.

Note I simply added a host file entry for "remote_Host" to my local machine for the demo.

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