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diff -Naur scponly-4.8.orig/CHANGELOG scponly-4.8/CHANGELOG
--- scponly-4.8.orig/CHANGELOG 2008-01-15 15:26:13.000000000 +0900
+++ scponly-4.8/CHANGELOG 2009-03-18 21:29:48.000000000 +0900
@@ -1,3 +1,9 @@
+CVS
+ Update the SECURITY document to include a reference to /etc/popt and ~/.popt as
+ they relate to rsync.
+ Fix for rsync-3.0 which now uses a short -e option, with an optional argument as
+ a server side option indicating protocol compatibility.
+
scponly v4.8 - jan 14 2008
fix support for quota and passwd when running within the chroot (exec pre-chroot)
disallow rsync and svnserve from being run as daemons that listen on a port
diff -Naur scponly-4.8.orig/SECURITY scponly-4.8/SECURITY
--- scponly-4.8.orig/SECURITY 2008-01-15 15:26:13.000000000 +0900
+++ scponly-4.8/SECURITY 2009-03-18 21:29:48.000000000 +0900
@@ -28,6 +28,10 @@
svn, svnserve, rsync, and unison
+ Note specifically that rsync uses popt for parsing command line arguments
+ and popt explicitly checks /etc/popt and $HOME/.popt for aliases. Thus,
+ users can likely bypass argument checking for rsync.
+
4) Make sure that all files required for the chroot have the IMMUTABLE and
UNDELETABLE bits set. Other bits might also be prudent. See: man 1 chattr.
@@ -39,13 +43,16 @@
~/.ssh, ~/.unison, ~/.subversion
NOTE: depending on file permissions in the above, ssh, unison, and
- subversion may not work correctly.
+ subversion may not work correctly. Also note that the location of the
+ above directories is sometimes system dependent, so please check the
+ documentation specific to your system.
7) Make sure that every directory the users have write permissions to are
on a filesystem that is mounted NODEV, NOEXEC. Eg. Make sure that they
cannot execute files that they have permissions to upload. They should
also not need permissions to create any devices. If the user can't execute
- any files that he has access to upload, then you need not worry about the
+ any files that he has access to upload and the executable files on the
+ system are not considered harmful, then you need not worry about the
security problems referencing svn/svnserve above!
8) Monitor your logs! If you start to see something funny, odd, or strange in
diff -Naur scponly-4.8.orig/helper.c scponly-4.8/helper.c
--- scponly-4.8.orig/helper.c 2008-01-15 15:26:13.000000000 +0900
+++ scponly-4.8/helper.c 2009-03-18 21:29:48.000000000 +0900
@@ -6,17 +6,15 @@
#include <sys/types.h> /* for stat, getpwuid */
#include <sys/stat.h> /* for stat */
#include <unistd.h> /* for exit, access, getpwuid, execve, getopt */
-#ifdef HAVE_GETOPT_H
-#include <getopt.h> /* for getopt */
-#endif
#include <errno.h> /* for debugging */
#include <pwd.h> /* to get username for config parsing */
#include <time.h> /* time */
#include <libgen.h> /* basename */
#include <stdlib.h> /* realloc */
#include <syslog.h>
-#include "scponly.h"
+
#include "config.h"
+#include "scponly.h" /* includes getopt */
#ifdef HAVE_GLOB
#include <glob.h> /* for glob() */
@@ -26,6 +24,11 @@
#endif
#endif
+#ifdef RSYNC_COMPAT
+#define RSYNC_ARG_SERVER 0x01
+#define RSYNC_ARG_EXECUTE 0x02
+#endif
+
#define MAX(x,y) ( ( x > y ) ? x : y )
#define MIN(x,y) ( ( x < y ) ? x : y )
@@ -164,6 +167,13 @@
int ch;
int ac=0;
int longopt_index = 0;
+#ifdef RSYNC_COMPAT
+ /*
+ * bitwise flag: 0x01 = server, 0x02 = -e.
+ * Thus 0x03 is allowed and 0x01 is allowed, but 0x02 is not allowed
+ */
+ int rsync_flags = 0;
+#endif /* RSYNC_COMPAT */
while (cmdarg != NULL)
{
@@ -207,7 +217,7 @@
* otherwise, try a glibc-style reset of the global getopt vars
*/
optind=0;
-#endif
+#endif /* HAVE_OPTRESET */
/*
* tell getopt to only be strict if the 'opts' is well defined
*/
@@ -216,28 +226,49 @@
debug(LOG_DEBUG, "getopt processing returned '%c' (%s)", ch, logstamp());
+#ifdef RSYNC_COMPAT
+ if (exact_match(cmdarg->name, PROG_RSYNC) && (ch == 's' || ch == 'e')) {
+ if (ch == 's')
+ rsync_flags |= RSYNC_ARG_SERVER;
+ else
+ /* -e */
+ rsync_flags |= RSYNC_ARG_EXECUTE;
+ debug(LOG_DEBUG, "rsync_flags are now set to: %0x", rsync_flags);
+ }
+ else
+#endif /* RSYNC_COMPAT */
+
/* if the character is found in badarg, then it's not a permitted option */
if (cmdarg->badarg != NULL && (strchr(cmdarg->badarg, ch) != NULL))
{
syslog(LOG_ERR, "option '%c' or a related long option is not permitted for use with %s (arg was %s) (%s))",
- ch, cmdarg->name, optarg, logstamp());
+ ch, cmdarg->name, (optarg!=NULL ? optarg : "<NULL>"), logstamp());
return 1;
}
else if (cmdarg->strict && ch == '?')
{
syslog(LOG_ERR, "an unrecognized option was encountered while processing cmd %s (arg was %s) (%s))",
- cmdarg->name, optarg, logstamp());
+ cmdarg->name, (optarg!=NULL ? optarg : "<NULL>"), logstamp());
return 1;
}
}
-#elif
+#ifdef RSYNC_COMPAT
+ /* it's not safe if the execute flag was set and server was not set */
+ if ((rsync_flags & RSYNC_ARG_EXECUTE) != 0 && (rsync_flags & RSYNC_ARG_SERVER) == 0) {
+ syslog(LOG_ERR, "option 'e' is not allowed unless '--server' is also set with cmd %s (%s)",
+ PROG_RSYNC, logstamp());
+ return 1;
+ }
+#endif /* RSYNC_COMPAT */
+
+#elif /* HAVE_GETOPT */
/*
* make sure that processing doesn't continue if we can't validate a rsync check
* and if the getopt flag is set.
*/
syslog(LOG_ERR, "a getopt() argument check could not be performed for %s, recompile scponly without support for %s or rebuild scponly with getopt", av[0], av[0]);
return 1;
-#endif
+#endif /* HAVE_GETOPT */
}
else
/*
diff -Naur scponly-4.8.orig/scponly.c scponly-4.8/scponly.c
--- scponly-4.8.orig/scponly.c 2008-01-15 15:28:24.000000000 +0900
+++ scponly-4.8/scponly.c 2009-03-18 21:29:48.000000000 +0900
@@ -91,16 +91,18 @@
#ifdef RSYNC_COMPAT
struct option rsync_longopts[] = {
+ /* options we need to know about that are safe */
+ {"server", 0, 0, (int)'s'},
/* I use 'e' for val here because that's what's listed in cmd_arg_t->badarg */
- {"rsh", 1, 0, (int)'e'},
+ {"rsh", 1, 0, (int)'r'},
/* the following are disabled because they use daemon mode */
- {"daemon", 0, 0, (int)'e'},
- {"rsync-path", 1, 0, (int)'e'},
- {"address", 1, 0, (int)'e'},
- {"port", 1, 0, (int)'e'},
- {"sockopts", 1, 0, (int)'e'},
- {"config", 1, 0, (int)'e'},
- {"no-detach", 0, 0, (int)'e'},
+ {"daemon", 0, 0, (int)'d'},
+ {"rsync-path", 1, 0, (int)'d'},
+ {"address", 1, 0, (int)'d'},
+ {"port", 1, 0, (int)'d'},
+ {"sockopts", 1, 0, (int)'d'},
+ {"config", 1, 0, (int)'d'},
+ {"no-detach", 0, 0, (int)'d'},
{ NULL, 0, NULL, 0 },
};
#endif
@@ -157,7 +159,7 @@
{ PROG_SCP, 1, 1, "SoF", "dfl:prtvBCc:i:P:q1246S:o:F:", empty_longopts },
#endif
#ifdef RSYNC_COMPAT
- { PROG_RSYNC, 1, 0, "e", "e:", rsync_longopts },
+ { PROG_RSYNC, 1, 0, "rde", "e::", rsync_longopts },
#endif
#ifdef UNISON_COMPAT
{ PROG_UNISON, 0, 0, "-rshcmd", NULL, empty_longopts },
diff -Naur scponly-4.8.orig/scponly.h scponly-4.8/scponly.h
--- scponly-4.8.orig/scponly.h 2008-01-15 15:26:13.000000000 +0900
+++ scponly-4.8/scponly.h 2009-03-18 21:29:48.000000000 +0900
@@ -1,6 +1,9 @@
#include <stdio.h> /* FILENAME_MAX */
-#include <getopt.h> /* struct option */
-#include "config.h"
+#include "config.h" /* include before most other files */
+
+#ifdef HAVE_GETOPT_H
+#include <getopt.h> /* for struct option for getopt */
+#endif
#define MAX_USERNAME 32
#define MAX_REQUEST (1024) /* any request exceeding this is truncated */
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