sudo-project/sudo SUDO_1_9_8

Sudo 1.9.8

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It is now possible to transparently intercepting sub-commands executed by the original command run via sudo. Intercept support is implemented using LD_PRELOAD (or the equivalent supported by the system) and so has some limitations. The two main limitations are that only dynamic executables are supported and only the execl, execle, execlp, execv, execve, execvp, and execvpe library functions are currently intercepted. Its main use case is to support restricting privileged shells run via sudo.

To support this, there is a new intercept Defaults setting and an INTERCEPT command tag that can be used in sudoers. For example:

 Cmnd_Alias SHELLS=/bin/bash, /bin/sh, /bin/csh, /bin/ksh, /bin/zsh
 Defaults!SHELLS intercept

would cause sudo to run the listed shells in intercept mode. This can also be set on a per-rule basis. For example:

 Cmnd_Alias SHELLS=/bin/bash, /bin/sh, /bin/csh, /bin/ksh, /bin/zsh
 chuck ALL = INTERCEPT: SHELLS

would only apply intercept mode to user chuck when running one of the listed shells.

In intercept mode, sudo will not prompt for a password before running a sub-command and will not allow a set-user-ID or set-group-ID program to be run by default. The new intercept_authenticate and intercept_allow_setid sudoers settings can be used to change this behavior.

The new log_subcmds sudoers setting can be used to log additional commands run in a privileged shell. It uses the same mechanism as the intercept support described above and has the same limitations.

Support for logging sudo_logsrvd errors via syslog or to a file. Previously, most sudo_logsrvd errors were only visible in the debug log.

Better diagnostics when there is a TLS certificate validation error.

Using the += or -= operators in a Defaults setting that takes a string, not a list, now produces a warning from sudo and a syntax error from inside visudo.

Fixed a bug where the iolog_mode setting in sudoers and sudo_logsrvd had no effect when creating I/O log parent directories if the I/O log file name ended with the string XXXXXX.

Fixed a bug in the sudoers custom prompt code where the size parameter that was passed to the strlcpy() function was incorrect. No overflow was possible since the correct amount of memory was already pre-allocated.

The mksigname and mksiglist helper programs are now built with the host compiler, not the target compiler, when cross-compiling. Bug #989.

Fixed compilation error when the --enable-static-sudoers configure option was specified. This was due to a typo introduced in sudo 1.9.7. GitHub PR #113.