-## Remoteusage without password-free login requirement
-
-This is alternative to [[remoteusage|remoteusage]] where password-free
-login is not a requirement. See [[remoteusage|remoteusage]] page for
-other requirements and general information.
-
-This solution uses one pre-made ssh connection where the client is put
-into "master" mode (-M) for connection sharing. The wrapper script then
-uses the control socket created by this pre-made ssh connection for
-its own connection. As long as master ssh connection is live, slave
-can use it. Disconnecting master all future attempts to connect
-from the script will fail.
-
-At the end of this document there is information for some possible ways
-how master ssh connection can be done.
-
-## The script
-
-Write the following code to a file, for example `remote-notmuch.sh`.
-
- #!/bin/bash
-
- # http://notmuchmail.org/remoteusage/aboriginal/
-
- set -eu
- # To trace execution, uncomment next line.
- #BASH_XTRACEFD=6; exec 6>>remote-errors; echo -- >&6; set -x
-
- readonly SSH_CONTROL_SOCK='~'/.ssh/master-user@host:22
-
- readonly notmuch=notmuch
-
- printf -v ARGS '%q ' "$@" # bash feature
-
- readonly SSH_CONTROL_ARGS='-oControlMaster=no -S '$SSH_CONTROL_SOCK
-
- if ssh -q $SSH_CONTROL_ARGS 0.1 $notmuch $ARGS
- then exit 0
- else ev=$?
- fi
-
- # continuing here in case ssh exited with nonzero value.
-
- case $* in
- 'config get user.primary_email') echo 'nobody@nowhere.invalid'; exit 0 ;;
- 'config get user.name') echo 'nobody'; exit 0 ;;
- 'count'*'--batch'*) while read line; do echo 1; done; exit 0 ;;
- 'count'*) echo 1; exit 0 ;;
- 'search-tags'*) echo 'errors'; exit 0 ;;
- 'search'*'--output=tags'*) echo 'errors'; exit 0 ;;
- esac
-
- if ssh $SSH_CONTROL_ARGS -O check 0.1
- then
- echo ' Control socket is alive but something failed during data transmission.'
- exit $ev
- fi
-
- echo " See`sed '1d;2d;s/.//;q' "$0"` for help."
- #EOF
-
-Note the `0.1` in ssh command line. It is used to avoid any opportunistic
-behaviour ssh might do; for example if control socket is not alive ssh
-would attempt to do it's own ssh connection to remote ssh server. As
-address `0.1` is invalid this attempt will fail early.
-
-## Test
-
-Easiest way to test this script is to run the pre-made ssh connection
-using the following command line:
-
- ssh -M -S '~'/.ssh/master-user@host:22 [user@]remotehost sleep 600
-
-(replace `[user@]remotehost` with your login info). Doing this the
-above wrapper script can be run unmodified. After the above command has
-been run on **one terminal**, enter `chmod +x remote-notmuch.sh` in
-**another terminal** and then test the script with
-
- ./remote-notmuch.sh help
-
-Note that the '~' in the ssh command line above is inside single quotes
-for a reason. In this case shell never expand it to `$HOME` -- ssh does
-it by not reading `$HOME` but checking the real user home directory
-from `/etc/passwd`. For security purposes this is just how it should
-be.
-
-## Tune
-
-The path `'~'/.ssh/master-user@host:22` might look too generic to be
-used as is as the control socket after initial testing (but it can
-be used). It is presented as a template for what could be configured
-to `$HOME/.ssh/config`. For example:
-
- Host *
- ControlPath ~/.ssh/master-%h@%p:%r
-
-is a good entry to be written in `$HOME/.ssh/config`;
-[[remoteusage|remoteusage]] uses the same. Now, let's say you'd
-make your pre-made ssh connection with command
-
- ssh -M alice@example.org
-
-After configuring
-`readonly SSH_CONTROL_SOCK='~'/.ssh/master-alice@example.org:22`
-to the `./remote-notmuch.sh` wrapper script testing with
-`./remote-notmuch.sh help` should work fine.
-
-## Configure Emacs on the client computer ##
-
-See the section *Configure Emacs on the client computer* in
-[[remoteusage|remoteusage]] how to do this. The instructions are the same.
-
-
-## Creating master connection
-
-As mentioned so many times, using this solution requires one pre-made
-ssh connection in "master" mode. The simplest way is to dedicate one
-terminal for the connection with shell access to the remote machine:
-
- ssh -M -S '~'/.ssh/master-user@host:22 [user@]remotehost
-
-One possibility is to have this dedicated terminal in a way that the
-connection has (for example 1 hour) timeout:
-
- ssh -M -S '~'/.ssh/master-user@host:22 [user@]remotehost sleep 3600
-
-The above holds the terminal. The next alternative puts the command in
-background:
-
- ssh -f -M -S '~'/.ssh/master-user@host:22 [user@]remotehost sleep 3600
-
-If you don't want this to timeout so soon, use a longer sleep, like 99999999
-(8 9:s, 1157 days, a bit more than 3 years).
-
-A more "exotic" solution would be to make a shell script running on remote
-machine, checking/inotifying when new mail arrives. When mail arrives it
-could send message back to local host, where a graphical client (to be written)
-pops up on display providing info about received mail (and exiting this
-graphical client connection to remote host is terminated).
-
-## Troubleshooting
-
-If you experience strange output when using from emacs first attempt to just
-run
-
- ./remote-notmuch.sh help
-
-from command line and observe output. If it looks as it should be next uncomment
-the line
-
- #BASH_XTRACEFD=6; exec 6>>remote-errors; echo -- >&6; set -x
-
-in `./remote-notmuch.sh` and attempt to use it from emacs again -- and then
-examine the contents of `remote-errors` in the working directory emacs was
-started.
projects / notmuch-wiki / blobdiff