From 97e3656176e3bfad5318d4133b6c76c845d53e22 Mon Sep 17 00:00:00 2001 From: Ryan Lortie Date: Tue, 10 Dec 2013 16:47:53 -0500 Subject: [PATCH] Add support for FreeBSD cap_init() and friends are Linux-specific, so only use them if we're on Linux. Add support for FreeBSD capabilities if we find to be available there. Add an #else (not Linux or FreeBSD) case with an #error requesting contributions for other platforms. This patch keeps the cap_init check in configure.ac but removes the error if it fails. This will ensure we link to -lcap if needed, but won't fail for the case that capabilities are part of the core system (as on FreeBSD). We do however, modify the header check to ensure we fail if there is no at all and we are on a system where it could be installed. The logic here is that it is better to give the user the chance to install it than it is to proceed silently with a disabled security feature on a system where it could easily be supported. --without-caps remains an option if the user wants to force it. https://bugs.freedesktop.org/show_bug.cgi?id=72580 --- configure.ac | 24 ++++++++++++++++-------- src/daemon/caps.c | 6 ++++++ 2 files changed, 22 insertions(+), 8 deletions(-) diff --git a/configure.ac b/configure.ac index 72e7695..3f2dec9 100644 --- a/configure.ac +++ b/configure.ac @@ -118,6 +118,10 @@ fi #### Determine host OS #### +# if the host has the possibility of sys/capability.h for dropping privileges +# used to determine if we should error out if it is not found +host_has_caps=0 + os_is_linux=0 os_is_win32=0 os_is_darwin=0 @@ -126,8 +130,13 @@ AC_MSG_CHECKING([host operating system]) case "$host_os" in linux*) AC_MSG_RESULT([linux]) + host_has_caps=1 os_is_linux=1 ;; + freebsd*) + AC_MSG_RESULT([freebsd]) + host_has_caps=1 + ;; darwin*) AC_MSG_RESULT([darwin]) os_is_darwin=1 @@ -595,17 +604,16 @@ AS_IF([test "x$HAVE_X11" = "x1"], AC_DEFINE([HAVE_X11], 1, [Have X11?])) CAP_LIBS='' AC_ARG_WITH([caps], - AS_HELP_STRING([--without-caps],[Omit support for POSIX capabilities.])) + AS_HELP_STRING([--without-caps],[Omit support for dropping capabilities.])) if test "x${with_caps}" != "xno"; then - AC_SEARCH_LIBS([cap_init], [cap], [], [ - if test "x${with_caps}" = "xyes" ; then - AC_MSG_ERROR([*** POSIX caps libraries not found]) - fi]) + AC_SEARCH_LIBS([cap_init], [cap], [], []) + + # Only give an error on hosts that we know could support capabilities AC_CHECK_HEADERS([sys/capability.h], [], [ - if test "x${with_caps}" = "xyes" ; then - AC_MSG_ERROR([*** POSIX caps headers not found]) - fi]) + if test "${host_has_caps}" = "1"; then + AC_MSG_ERROR([*** sys/capability.h not found. Use --without-caps to disable capabilities support.]) + fi]) fi #### Valgrind (optional) #### diff --git a/src/daemon/caps.c b/src/daemon/caps.c index 2251cb3..68b79ce 100644 --- a/src/daemon/caps.c +++ b/src/daemon/caps.c @@ -80,12 +80,18 @@ void pa_drop_root(void) { void pa_drop_caps(void) { #ifdef HAVE_SYS_CAPABILITY_H +#ifdef __linux cap_t caps; pa_assert_se(caps = cap_init()); pa_assert_se(cap_clear(caps) == 0); pa_assert_se(cap_set_proc(caps) == 0); pa_assert_se(cap_free(caps) == 0); +#elif __FreeBSD__ + pa_assert_se (cap_enter () == 0); #else +#error Don't know how to do capabilities on your system. Please send a patch. +#endif /* __linux */ +#else /* HAVE_SYS_CAPABILITY_H */ pa_log_warn("Normally all extra capabilities would be dropped now, but " "that's impossible because this Pulseaudio was built without " "libcap support."); -- 1.8.4.2