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authorKay Sievers <kay@vrfy.org>2012-04-10 13:39:02 +0200
committerKay Sievers <kay@vrfy.org>2012-04-10 14:13:38 +0200
commitd7832d2c6e0ef5f2839a2296c1cc2fc85c7d9632 (patch)
tree5b10dc4909bd956638837504d95d879ea96a86ec /src/shared/capability.c
parent304b9f30781b8625c1f84fd27205f2707d4843b1 (diff)
util: move all to shared/ and split external dependencies in separate internal libraries
Before: $ ldd /lib/systemd/systemd-timestamp linux-vdso.so.1 => (0x00007fffb05ff000) libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f90aac57000) libcap.so.2 => /lib64/libcap.so.2 (0x00007f90aaa53000) librt.so.1 => /lib64/librt.so.1 (0x00007f90aa84a000) libc.so.6 => /lib64/libc.so.6 (0x00007f90aa494000) /lib64/ld-linux-x86-64.so.2 (0x00007f90aae90000) libdl.so.2 => /lib64/libdl.so.2 (0x00007f90aa290000) libattr.so.1 => /lib64/libattr.so.1 (0x00007f90aa08a000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f90a9e6e000) After: $ ldd systemd-timestamp linux-vdso.so.1 => (0x00007fff3cbff000) libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f5eaa1c3000) librt.so.1 => /lib64/librt.so.1 (0x00007f5ea9fbb000) libc.so.6 => /lib64/libc.so.6 (0x00007f5ea9c04000) /lib64/ld-linux-x86-64.so.2 (0x00007f5eaa3fc000) libdl.so.2 => /lib64/libdl.so.2 (0x00007f5ea9a00000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f5ea97e4000)
Diffstat (limited to 'src/shared/capability.c')
-rw-r--r--src/shared/capability.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/src/shared/capability.c b/src/shared/capability.c
new file mode 100644
index 000000000..b8002159e
--- /dev/null
+++ b/src/shared/capability.c
@@ -0,0 +1,86 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <stdarg.h>
+#include <ctype.h>
+#include <sys/capability.h>
+#include <sys/prctl.h>
+
+#include "macro.h"
+#include "capability.h"
+#include "util.h"
+#include "log.h"
+
+int have_effective_cap(int value) {
+ cap_t cap;
+ cap_flag_value_t fv;
+ int r;
+
+ if (!(cap = cap_get_proc()))
+ return -errno;
+
+ if (cap_get_flag(cap, value, CAP_EFFECTIVE, &fv) < 0)
+ r = -errno;
+ else
+ r = fv == CAP_SET;
+
+ cap_free(cap);
+ return r;
+}
+
+unsigned long cap_last_cap(void) {
+ static __thread unsigned long saved;
+ static __thread bool valid = false;
+ unsigned long p;
+
+ if (valid)
+ return saved;
+
+ p = (unsigned long) CAP_LAST_CAP;
+
+ if (prctl(PR_CAPBSET_READ, p) < 0) {
+
+ /* Hmm, look downwards, until we find one that
+ * works */
+ for (p--; p > 0; p --)
+ if (prctl(PR_CAPBSET_READ, p) >= 0)
+ break;
+
+ } else {
+
+ /* Hmm, look upwards, until we find one that doesn't
+ * work */
+ for (;; p++)
+ if (prctl(PR_CAPBSET_READ, p+1) < 0)
+ break;
+ }
+
+ saved = p;
+ valid = true;
+
+ return p;
+}