Add support for FreeBSD <sys/capability.h>

[pulseaudio] / src / daemon / caps.c

diff --git a/src/daemon/caps.c b/src/daemon/caps.c
index 5b4008a58d8bd043d9429d1f5c90ae4c1be5c4d4..68b79cebd2e53943e2ec8355f20a9130e80702f9 100644 (file)
--- a/src/daemon/caps.c
+++ b/src/daemon/caps.c
@@ -1,5 +1,3 @@
-/* $Id$ */
-
 /***
   This file is part of PulseAudio.
 
@@ -8,7 +6,7 @@
 
   PulseAudio is free software; you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published
-  by the Free Software Foundation; either version 2 of the License,
+  by the Free Software Foundation; either version 2.1 of the License,
   or (at your option) any later version.
 
   PulseAudio is distributed in the hope that it will be useful, but
@@ -28,20 +26,15 @@
 
 #include <unistd.h>
 #include <errno.h>
-#include <string.h>
 #include <sys/types.h>
+
+#include <pulsecore/i18n.h>
 #include <pulsecore/macro.h>
+#include <pulsecore/log.h>
 
 #ifdef HAVE_SYS_CAPABILITY_H
 #include <sys/capability.h>
 #endif
-#ifdef HAVE_SYS_PRCTL_H
-#include <sys/prctl.h>
-#endif
-
-#include <pulsecore/core-error.h>
-
-#include <pulsecore/log.h>
 
 #include "caps.h"
 
@@ -51,100 +44,56 @@ int setresgid(gid_t r, gid_t e, gid_t s);
 int setresuid(uid_t r, uid_t e, uid_t s);
 #endif
 
-#ifdef HAVE_GETUID
-
 /* Drop root rights when called SUID root */
 void pa_drop_root(void) {
-    uid_t uid = getuid();
 
-    if (uid == 0 || geteuid() != 0)
-        return;
+#ifdef HAVE_GETUID
+    uid_t uid;
+    gid_t gid;
 
-    pa_log_info("Dropping root priviliges.");
+    pa_log_debug(_("Cleaning up privileges."));
+    uid = getuid();
+    gid = getgid();
 
 #if defined(HAVE_SETRESUID)
-    setresuid(uid, uid, uid);
+    pa_assert_se(setresuid(uid, uid, uid) >= 0);
+    pa_assert_se(setresgid(gid, gid, gid) >= 0);
 #elif defined(HAVE_SETREUID)
-    setreuid(uid, uid);
+    pa_assert_se(setreuid(uid, uid) >= 0);
+    pa_assert_se(setregid(gid, gid) >= 0);
 #else
-    setuid(uid);
-    seteuid(uid);
+    pa_assert_se(setuid(uid) >= 0);
+    pa_assert_se(seteuid(uid) >= 0);
+    pa_assert_se(setgid(gid) >= 0);
+    pa_assert_se(setegid(gid) >= 0);
 #endif
-}
 
-#else
-
-void pa_drop_root(void) {
-}
+    pa_assert_se(getuid() == uid);
+    pa_assert_se(geteuid() == uid);
+    pa_assert_se(getgid() == gid);
+    pa_assert_se(getegid() == gid);
 
+    if (uid != 0)
+        pa_drop_caps();
 #endif
-
-#if defined(HAVE_SYS_CAPABILITY_H) && defined(HAVE_SYS_PRCTL_H)
-
-/* Limit permitted capabilities set to CAPSYS_NICE */
-int pa_limit_caps(void) {
-    int r = -1;
-    cap_t caps;
-    cap_value_t nice_cap = CAP_SYS_NICE;
-
-    caps = cap_init();
-    pa_assert(caps);
-    cap_clear(caps);
-    cap_set_flag(caps, CAP_EFFECTIVE, 1, &nice_cap, CAP_SET);
-    cap_set_flag(caps, CAP_PERMITTED, 1, &nice_cap, CAP_SET);
-
-    if (cap_set_proc(caps) < 0)
-        goto fail;
-
-    if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) < 0)
-        goto fail;
-
-    pa_log_info("Dropped capabilities successfully.");
-
-    r = 1;
-
-fail:
-    cap_free(caps);
-
-    return r;
 }
 
-/* Drop all capabilities, effectively becoming a normal user */
-int pa_drop_caps(void) {
+void pa_drop_caps(void) {
+#ifdef HAVE_SYS_CAPABILITY_H
+#ifdef __linux
     cap_t caps;
-    int r = -1;
-
-    caps = cap_init();
-    pa_assert(caps);
-
-    cap_clear(caps);
-
-    prctl(PR_SET_KEEPCAPS, 0, 0, 0, 0);
-
-    if (cap_set_proc(caps) < 0) {
-        pa_log("Failed to drop capabilities: %s", pa_cstrerror(errno));
-        goto fail;
-    }
-
-    r = 0;
-
-fail:
-    cap_free(caps);
-
-    return r;
-}
-
+    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
-
-/* NOOPs in case capabilities are not available. */
-int pa_limit_caps(void) {
-    return 0;
-}
-
-int pa_drop_caps(void) {
-    pa_drop_root();
-    return 0;
-}
-
+#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.");
 #endif
-
+}