diff options
| author | Gregory Neil Shapiro <gshapiro@FreeBSD.org> | 2008-08-28 04:33:50 +0000 |
|---|---|---|
| committer | Gregory Neil Shapiro <gshapiro@FreeBSD.org> | 2008-08-28 04:33:50 +0000 |
| commit | e8e0e5823adff1aed6bf456d75e58353e6dcf68e (patch) | |
| tree | 366be2f317b4d052916d4861096c4a53ba6f9a26 /smrsh/smrsh.0 | |
| parent | aa651f666c6d33d54b6572c19534539ed5ae7637 (diff) | |
Import sendmail 8.14.3 and clean up svn properties as documented in:vendor/sendmail/8.14.3
Notes
svn path=/vendor/sendmail/dist/; revision=182329
svn path=/vendor/sendmail/8.14.3/; revision=182330; tag=vendor/sendmail/8.14.3
Diffstat (limited to 'smrsh/smrsh.0')
| -rw-r--r-- | smrsh/smrsh.0 | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/smrsh/smrsh.0 b/smrsh/smrsh.0 new file mode 100644 index 000000000000..65fc2f09981f --- /dev/null +++ b/smrsh/smrsh.0 @@ -0,0 +1,65 @@ +SMRSH(8) SMRSH(8) + + + +NNAAMMEE + smrsh - restricted shell for sendmail + +SSYYNNOOPPSSIISS + ssmmrrsshh --cc command + +DDEESSCCRRIIPPTTIIOONN + The _s_m_r_s_h program is intended as a replacement for _s_h for use in the + ``prog'' mailer in _s_e_n_d_m_a_i_l(8) configuration files. It sharply limits + the commands that can be run using the ``|program'' syntax of _s_e_n_d_m_a_i_l + in order to improve the over all security of your system. Briefly, + even if a ``bad guy'' can get sendmail to run a program without going + through an alias or forward file, _s_m_r_s_h limits the set of programs that + he or she can execute. + + Briefly, _s_m_r_s_h limits programs to be in a single directory, by default + /usr/adm/sm.bin, allowing the system administrator to choose the set of + acceptable commands, and to the shell builtin commands ``exec'', + ``exit'', and ``echo''. It also rejects any commands with the charac- + ters ``', `<', `>', `;', `$', `(', `)', `\r' (carriage return), or `\n' + (newline) on the command line to prevent ``end run'' attacks. It + allows ``||'' and ``&&'' to enable commands like: ``"|exec + /usr/local/bin/filter || exit 75"'' + + Initial pathnames on programs are stripped, so forwarding to + ``/usr/ucb/vacation'', ``/usr/bin/vacation'', + ``/home/server/mydir/bin/vacation'', and ``vacation'' all actually for- + ward to ``/usr/adm/sm.bin/vacation''. + + System administrators should be conservative about populating the + sm.bin directory. For example, a reasonable additions is _v_a_c_a_t_i_o_n(1), + and the like. No matter how brow-beaten you may be, never include any + shell or shell-like program (such as _p_e_r_l(1)) in the sm.bin directory. + Note that this does not restrict the use of shell or perl scripts in + the sm.bin directory (using the ``#!'' syntax); it simply disallows + execution of arbitrary programs. Also, including mail filtering pro- + grams such as _p_r_o_c_m_a_i_l(1) is a very bad idea. _p_r_o_c_m_a_i_l(1) allows users + to run arbitrary programs in their _p_r_o_c_m_a_i_l_r_c(5). + +CCOOMMPPIILLAATTIIOONN + Compilation should be trivial on most systems. You may need to use + -DSMRSH_PATH=\"_p_a_t_h\" to adjust the default search path (defaults to + ``/bin:/usr/bin:/usr/ucb'') and/or -DSMRSH_CMDDIR=\"_d_i_r\" to change the + default program directory (defaults to ``/usr/adm/sm.bin''). + +FFIILLEESS + /usr/adm/sm.bin - default directory for restricted programs on most OSs + + /var/adm/sm.bin - directory for restricted programs on HP UX and + Solaris + + /usr/libexec/sm.bin - directory for restricted programs on FreeBSD (>= + 3.3) and DragonFly BSD + + +SSEEEE AALLSSOO + sendmail(8) + + + + $Date: 2004/08/06 03:55:35 $ SMRSH(8) |