Ssh command from Qt

问题:

I have a problem with ssh in my Qt application. I need to run a command which removes a file on a remote server. I tried to use a QProcess class to achieve it. So I pass "ssh" as a name of command and necessary args. In common it looks like this:

QStringList params;    
params.append(" user@" + ::host +
              " \"rm /tmp/" + ::fileName + "\"");
d->impDelProcess->start("ssh", params);

But after all it keeps asking a password, though I generated ssh keys and copied a public key to the remote server. Moreover, when I run the command above in the terminal like this:

ssh user@host "rm /path/fileName"

it works perfect. The file is deleted and no password is asked. So, the problem is somwhere in QProcess. Is any way to get rid of asking a password? Thank you!

回答1:

Those are separate arguments, when you use string list. Try this:

params.append("user@" + ::host");
params.append("rm /tmp/" + ::fileName);

That will make Qt pass two arguments for ssh, the login string and the command to execute at remote host.

Important note! Above assumes ::filename does not contain spaces or anything else nasty!. You can get around spaces with this:

params.append("rm '/tmp/" + ::fileName + "'");

But it won't help against wild cards or .. in path... Imagine if file name was ../home/user/* for example... So that is better be trusted input, or you need to sanitize it (but that is beyond scope of this answer).

---

What you do in the question code is to construct a single argument, equivalent to this shell command line:

ssh 'user@host "rm /path/filename"'