| 1 |
On Sat, Jul 5, 2014 at 9:41 PM, Chris Stankevitz |
| 2 |
<chrisstankevitz@×××××.com> wrote: |
| 3 |
> |
| 4 |
> ssh is asking me for my passphrase using a terrible program called |
| 5 |
> "pinentry". It's terrible for a bunch of reasons, and if you are |
| 6 |
> interested you can just google "pinentry sucks". |
| 7 |
> |
| 8 |
|
| 9 |
Probably more a case of "X11 sucks." Historically password entry into |
| 10 |
X11 windows has always been problematic, because in general any client |
| 11 |
connected to an X server can evesdrop on data entered into any other |
| 12 |
window on the server. That is especially problematic when you |
| 13 |
remember that X was supposed to work on a network. It isn't as bad on |
| 14 |
your typical desktop setup, but applications like pinentry are often |
| 15 |
designed with the network scenario in mind. |
| 16 |
|
| 17 |
Imagine that you're on an X terminal at work. You have clients |
| 18 |
connected to your terminal from 47 different servers that you |
| 19 |
administer. Maybe you have firefox open from a workstation you |
| 20 |
administer at customer A who is having firewall issues and you're |
| 21 |
trying to get a sense of what things look like from inside. Perhaps |
| 22 |
you have a mail client open on customer B's server. You punch in your |
| 23 |
password for customer B so that the mail client can retrieve your mail |
| 24 |
there, and now the trojaned firefox at customer A has your password |
| 25 |
credentials for customer B. So, you have things like the feature in |
| 26 |
xterm which captures all keyboard input so that you can enter a |
| 27 |
password securely, but it probably breaks things like copy/paste and |
| 28 |
you have to toggle it on/off since while it is on no other window on |
| 29 |
your server can listen to the keyboard. |
| 30 |
|
| 31 |
This wasn't really how X11 ended up being used, but back in the day it |
| 32 |
was how it was designed to work. Well, except for the part where X11 |
| 33 |
is crippled when you have more than a few milliseconds in latency, so |
| 34 |
nobody runs clients on remote servers. But, you still get all the |
| 35 |
baggage. |
| 36 |
|
| 37 |
I'm not familiar with the internals of pinentry, but this probably why |
| 38 |
you're frustrated with it. |
| 39 |
|
| 40 |
In any case, I suspect that gpg-agent is actually serving passwords to |
| 41 |
openssh, so the file you want is ~/.gnupg/gpg-agent.conf - it probably |
| 42 |
contains the line "pinentry-program /usr/bin/pinentry". If you trust |
| 43 |
all your X clients you can set the option no-grab in the file which |
| 44 |
will probably allow copy/paste/etc to work with the entry window. |
| 45 |
|
| 46 |
Rich |
Archives