2 # Name: /usr/local/bin/rrsync (should also have a symlink in /usr/bin)
3 # Purpose: Restricts rsync to subdirectory declared in .ssh/authorized_keys
4 # Author: Joe Smith <js-cgi@inwap.com> 30-Sep-2004
5 # Modified by: Wayne Davison <wayned@samba.org>
10 use File::Glob ':glob';
12 # You may configure these values to your liking. See also the section
13 # of options if you want to disable any options that rsync accepts.
14 use constant RSYNC => '/usr/bin/rsync';
15 use constant LOGFILE => 'rrsync.log';
18 Use 'command="$0 [-ro] SUBDIR"'
19 in front of lines in $ENV{HOME}/.ssh/authorized_keys
22 our $ro = (@ARGV && $ARGV[0] eq '-ro') ? shift : ''; # -ro = Read-Only
24 die "$0: No subdirectory specified\n$Usage" unless defined $subdir;
25 $subdir = abs_path($subdir);
26 die "$0: Restricted directory does not exist!\n" if $subdir ne '/' && !-d $subdir;
28 # The client uses "rsync -av -e ssh src/ server:dir/", and sshd on the server
29 # executes this program when .ssh/authorized_keys has 'command="..."'.
31 # command="rrsync logs/client" ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAIEAzGhEeNlPr...
32 # command="rrsync -ro results" ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAIEAmkHG1WCjC...
34 # Format of the envrionment variables set by sshd:
35 # SSH_ORIGINAL_COMMAND=rsync --server -vlogDtpr --partial . ARG # push
36 # SSH_ORIGINAL_COMMAND=rsync --server --sender -vlogDtpr --partial . ARGS # pull
37 # SSH_CONNECTION=client_addr client_port server_port
39 my $command = $ENV{SSH_ORIGINAL_COMMAND};
40 die "$0: Not invoked via sshd\n$Usage" unless defined $command;
41 die "$0: SSH_ORIGINAL_COMMAND='$command' is not rsync\n" unless $command =~ s/^rsync\s+//;
42 our $am_sender = $command =~ /^--server\s+--sender\s/; # Restrictive on purpose!
43 die "$0 -ro: sending to read-only server not allowed\n" if $ro && !$am_sender;
45 ### START of options data produced by the cull_options script. ###
47 # These options are the only options that rsync might send to the server,
48 # and only in the option format that the stock rsync produces.
50 # To disable a short-named option, add its letter to this string:
51 our $short_disabled = '';
53 our $short_no_arg = 'CDHIKLORSWbcdglnoprtuvxz'; # DO NOT REMOVE ANY
54 our $short_with_num = 'B'; # DO NOT REMOVE ANY
56 # To disable a long-named option, change its value to a -1. The values mean:
57 # 0 = the option has no arg; 1 = the arg doesn't need any checking; 2 = only
58 # check the arg when receiving; and 3 = always check the arg.
65 'copy-unsafe-links' => 0,
72 'delete-excluded' => 0,
79 'ignore-existing' => 0,
87 'no-implied-dirs' => 0,
90 'only-write-batch' => 1,
93 'remove-sent-files' => $ro ? -1 : 0,
103 ### END of options data produced by the cull_options script. ###
105 if ($short_disabled ne '') {
106 $short_no_arg =~ s/[$short_disabled]//go;
107 $short_with_num =~ s/[$short_disabled]//go;
109 $short_no_arg = "[$short_no_arg]" if length($short_no_arg) > 1;
110 $short_with_num = "[$short_with_num]" if length($short_with_num) > 1;
112 my $write_log = -f LOGFILE && open(LOG, '>>', LOGFILE);
114 chdir($subdir) or die "$0: Unable to chdir to restricted dir: $!\n";
120 while ($command =~ /((?:[^\s\\]+|\\.[^\s\\]*)+)/g) {
123 push(@opts, check_arg($last_opt, $_, $check_type));
125 } elsif ($in_options) {
130 next if /^-$short_no_arg+$/o || /^-$short_with_num\d+$/o;
132 my($opt,$arg) = /^--([^=]+)(?:=(.*))?$/;
135 my $ct = $long_opt{$opt};
136 last unless defined $ct;
144 $arg = check_arg($opt, $arg, $ct);
145 $opts[-1] =~ s/=.*/=$arg/;
150 } elsif ($short_disabled ne '') {
151 $disabled = /^-$short_no_arg*([$short_disabled])/o;
155 last unless $disabled; # Generate generic failure
156 die "$0: option $opt has been disabled on this server.\n";
159 if ($subdir ne '/') {
160 # Validate args to ensure they don't try to leave our restricted dir.
164 die "Do not use .. in any path!\n" if m#(^|/)\\?\.\\?\.(\\?/|$)#;
166 push(@args, bsd_glob($_, GLOB_LIMIT|GLOB_NOCHECK|GLOB_BRACE|GLOB_QUOTE));
169 die "$0: invalid rsync-command syntax or options\n" if $in_options;
171 @args = ( '.' ) if !@args;
174 my ($mm,$hh) = (localtime)[1,2];
175 my $host = $ENV{SSH_CONNECTION} || 'unknown';
176 $host =~ s/ .*//; # Keep only the client's IP addr
177 $host =~ s/^::ffff://;
178 $host = gethostbyaddr(inet_aton($host),AF_INET) || $host;
179 printf LOG "%02d:%02d %-13s [%s]\n", $hh, $mm, $host, "@opts @args";
183 # Note: This assumes that the rsync protocol will not be maliciously hijacked.
184 exec(RSYNC, @opts, @args) or die "exec(rsync @opts @args) failed: $? $!";
188 my($opt, $arg, $type) = @_;
189 $arg =~ s/\\(.)/$1/g;
190 if ($subdir ne '/' && ($type == 3 || ($type == 2 && !$am_sender))) {
192 die "Do not use .. in --$opt; anchor the path at the root of your restricted dir.\n"
193 if $arg =~ m#(^|/)\.\.(/|$)#;
194 $arg =~ s#^/#$subdir/#;