A tempfile was often used by Tomb in order to parse the stderr output of
gpg and detect if the password is correct or not. The tempfile was not
holding any secret information (see #162) yet this is an improvement for
Tomb's deniability since there is now much less going on in the temp
firectory.
Added the --tmp flag for manual selection of the temporary directory, whose security should really be up to sysadmins when configuring operating systems. Default is ZSh TMPPREFIX usually set to /tmp/zsh which, if not existing, will be created as world writable with a sticky bit.
This commit also includes a cleanup of commandline options and a fix to swap check.
Now there is no more writing of cleartext secrets in any tempfile,
the last case was in setkey and is now eliminated. Tempfile creation
is cleaner. Related to issue #162
Using the 'cleartext' name for a key will read it from stdin and
expect it to be unencrypted. This is an unsafe mode of operation,
but useful i.e. to open remote tombs by piping the key over ssh,
or using a different software than Tomb to de/crypt keys.
This commit also renames the flag --unsecure-dev-mode into --unsafe
and includes a minor fix to the last opened date shown on open.
Addressing issue #161
after fixing issue #154 with echo here we revert to using print with
options -R -n which sort the same effect. Print is preferred since it
executes the built-in command without any possible ambiguity. We don't
want to expose secrets to an external executable in case of a simple
attack that would change the env PATH to use a rootkitted echo.
Switched to use echo with -E flag to disable escapes in keys: escape
strings were discarded cryptsetup tomb operations when they were present
in the decoded key random passphrase. Issue #154
The solution adopted here includes wrapping all cryptsetup operations to
unify the behaviour adopted.
Worth noting that this problem possibly breaks all tombs and keys
created using the unstable Tomb from git development in the past 2
months. Regression tests with previous stable releases are OK.
