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#! /bin/sh /usr/share/dpatch/dpatch-run
## 04_drop-capabilities.dpatch by <fpeters@debian.org>
##
## All lines beginning with `## DP:' are a description of the patch.
## DP: Drop all capabilities but CAP_NET_RAW
@DPATCH@
diff -urNad --exclude=CVS --exclude=.svn ./config.h.in /tmp/dpep-work.rT2mW8/ethereal-0.10.12/config.h.in
--- ./config.h.in 2005-07-31 12:50:13.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/config.h.in 2005-07-31 12:54:13.000000000 +0200
@@ -55,6 +55,9 @@
/* Define if krb5.h defines KEYTYPE_ARCFOUR_56 */
#undef HAVE_KEYTYPE_ARCFOUR_56
+/* Define if libcap is available to restrict process capabilities */
+#undef HAVE_LIBCAP
+
/* Define to use libpcap library */
#undef HAVE_LIBPCAP
diff -urNad --exclude=CVS --exclude=.svn ./configure.in /tmp/dpep-work.rT2mW8/ethereal-0.10.12/configure.in
--- ./configure.in 2005-07-31 12:50:26.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/configure.in 2005-07-31 12:54:13.000000000 +0200
@@ -737,6 +737,47 @@
fi
+dnl libcap check
+AC_MSG_CHECKING(whether to use libcap to improve security)
+
+AC_ARG_WITH(cap,
+[ --with-cap[[=DIR]] use libcap (located in directory DIR, if supplied) to improve security. [[default=yes, if available]]],
+[
+ if test $withval = no
+ then
+ want_cap=no
+ elif test $withval = yes
+ then
+ want_cap=yes
+ else
+ want_cap=yes
+ cap_dir=$withval
+ fi
+],[
+ #
+ # Use libcap if it's present, otherwise don't.
+ #
+ want_cap=ifavailable
+ cap_dir=
+])
+if test "x$want_cap" = "xno" ; then
+ AC_MSG_RESULT(no)
+ cap_message="no (disabled by explicit request)"
+else
+ AC_MSG_RESULT(yes)
+ AC_CHECK_LIB(cap, cap_init, [
+ AC_DEFINE(HAVE_LIBCAP, 1, [
+ Define if libcap is available to restrict process capabilities
+ ])
+ LIBS="$LIBS -lcap"
+ cap_message="yes"
+ ], [
+ AC_MSG_WARN([libcap check failed])
+ cap_message="no (check failed)"
+ ])
+fi
+
+
dnl Check if wireshark should be installed setuid
AC_ARG_ENABLE(setuid-install,
[ --enable-setuid-install install ethereal as setuid. DANGEROUS!!! [default=no]],enable_setuid_install=$enableval,enable_setuid_install=no)
@@ -1322,3 +1363,4 @@
echo " Use SSL crypto library : $ssl_message"
echo " Use IPv6 name resolution : $enable_ipv6"
echo " Use UCD SNMP/Net-SNMP library : $snmp_libs_message"
+echo " Use cap library : $cap_message"
diff -urNad --exclude=CVS --exclude=.svn ./gtk/main.c /tmp/dpep-work.rT2mW8/ethereal-0.10.12/gtk/main.c
--- ./gtk/main.c 2005-07-31 12:50:37.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/gtk/main.c 2005-07-31 12:54:13.000000000 +0200
@@ -1671,6 +1671,9 @@
runtime_info_str = g_string_new("Running ");
get_runtime_version_info(runtime_info_str);
+#ifdef HAVE_LIBCAP
+ dropexcesscapabilities();
+#endif
/*** "pre-scan" the command line parameters, if we have "console only" parameters ***/
/* (e.g. don't start GTK+, if we only have to show the command line help) */
diff -urNad --exclude=CVS --exclude=.svn ./tethereal.c /tmp/dpep-work.rT2mW8/ethereal-0.10.12/tethereal.c
--- ./tethereal.c 2005-07-31 12:49:37.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/tethereal.c 2005-07-31 12:54:13.000000000 +0200
@@ -663,6 +663,10 @@
capture_opts_init(&capture_opts, NULL /* cfile */);
#endif
+#ifdef HAVE_LIBCAP
+ dropexcesscapabilities();
+#endif
+
set_timestamp_setting(TS_RELATIVE);
/* Register all dissectors; we must do this before checking for the
diff -urNad --exclude=CVS --exclude=.svn ./util.c /tmp/dpep-work.rT2mW8/ethereal-0.10.12/util.c
--- ./util.c 2005-07-31 12:49:42.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/util.c 2005-07-31 12:56:35.000000000 +0200
@@ -69,6 +69,10 @@
#include <windows.h>
#endif
+#ifdef HAVE_LIBCAP
+#include <sys/capability.h>
+#endif
+
#include "util.h"
/*
@@ -311,3 +315,46 @@
}
return "";
}
+
+
+#ifdef HAVE_LIBCAP
+void dropexcesscapabilities(void)
+{
+ cap_t cap_d;
+ cap_value_t cap_values[] = {
+ /* capabilities we need to keep */
+ CAP_NET_RAW,
+ CAP_DAC_READ_SEARCH
+ };
+ cap_flag_value_t current_cap;
+
+ cap_d = cap_get_proc();
+ if (!cap_d) {
+ g_warning("Could not get capabilities\n");
+ return;
+ }
+
+ cap_get_flag(cap_d, CAP_NET_RAW, CAP_EFFECTIVE, ¤t_cap);
+ cap_free(&cap_d);
+ if (current_cap == CAP_CLEAR) {
+ return;
+ }
+
+ cap_d = cap_init();
+ if (!cap_d) {
+ g_warning("Could not alloc cap struct\n");
+ return;
+ }
+
+ cap_clear(cap_d);
+ cap_set_flag(cap_d, CAP_PERMITTED, 2, cap_values, CAP_SET);
+ cap_set_flag(cap_d, CAP_EFFECTIVE, 2, cap_values, CAP_SET);
+
+ if (cap_set_proc(cap_d) != 0) {
+ g_warning("Could not set capabilities: %s\n", strerror(errno));
+ cap_free(&cap_d);
+ return;
+ }
+ cap_free(&cap_d);
+}
+#endif /* HAVE_LIBCAP */
diff -urNad --exclude=CVS --exclude=.svn ./util.h /tmp/dpep-work.rT2mW8/ethereal-0.10.12/util.h
--- ./util.h 2005-07-31 12:49:42.000000000 +0200
+++ /tmp/dpep-work.rT2mW8/ethereal-0.10.12/util.h 2005-07-31 12:54:13.000000000 +0200
@@ -43,6 +43,15 @@
/* Create a capture filter for the connection */
char *get_conn_cfilter(void);
+#ifdef HAVE_LIBCAP
+/*
+ * Limit the potential impact of undiscovered security vulnerabilities by
+ * dropping all capabilities except the sniffer capability we need to do our
+ * job.
+ */
+void dropexcesscapabilities(void);
+#endif /* HAVE_LIBCAP */
+
#ifdef __cplusplus
}
#endif /* __cplusplus */
|
