[systemd-commits] 2 commits - src/shared src/timesync units/systemd-hostnamed.service.in units/systemd-networkd.service.in
Lennart Poettering
lennart at kemper.freedesktop.org
Sat May 31 23:55:28 PDT 2014
src/shared/capability.c | 71 ++++++++++++++++++++++++++++++++++++-
src/shared/capability.h | 2 +
src/shared/util.c | 3 -
src/timesync/timesyncd.c | 68 -----------------------------------
units/systemd-hostnamed.service.in | 2 -
units/systemd-networkd.service.in | 2 -
6 files changed, 76 insertions(+), 72 deletions(-)
New commits:
commit 40393d5247c4cd28625fdccbc2b78f3406d44c45
Author: Lennart Poettering <lennart at poettering.net>
Date: Sun Jun 1 08:54:09 2014 +0200
units: remove CAP_SYS_PTRACE capability from hostnamed/networkd
The ptrace capability was only necessary to detect virtualizations
environments. Since we changed the logic to determine this to not
require priviliges, there's no need to carry the CAP_SYS_PTRACE
capability anymore.
diff --git a/units/systemd-hostnamed.service.in b/units/systemd-hostnamed.service.in
index 4481259..79e22c1 100644
--- a/units/systemd-hostnamed.service.in
+++ b/units/systemd-hostnamed.service.in
@@ -13,7 +13,7 @@ Documentation=http://www.freedesktop.org/wiki/Software/systemd/hostnamed
[Service]
ExecStart=@rootlibexecdir@/systemd-hostnamed
BusName=org.freedesktop.hostname1
-CapabilityBoundingSet=CAP_SYS_ADMIN CAP_DAC_OVERRIDE CAP_SYS_PTRACE
+CapabilityBoundingSet=CAP_SYS_ADMIN
WatchdogSec=1min
PrivateTmp=yes
PrivateDevices=yes
diff --git a/units/systemd-networkd.service.in b/units/systemd-networkd.service.in
index fc3b14a..40ec90e 100644
--- a/units/systemd-networkd.service.in
+++ b/units/systemd-networkd.service.in
@@ -19,7 +19,7 @@ Type=notify
Restart=always
RestartSec=0
ExecStart=@rootlibexecdir@/systemd-networkd
-CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_BIND_SERVICE CAP_NET_BROADCAST CAP_NET_RAW CAP_SYS_PTRACE CAP_SYS_MODULE
+CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_BIND_SERVICE CAP_NET_BROADCAST CAP_NET_RAW CAP_SYS_MODULE
WatchdogSec=1min
[Install]
commit 966bff2660a13c82b70a1e1ac4f1a48bb33d7f7e
Author: Lennart Poettering <lennart at poettering.net>
Date: Sun Jun 1 08:49:33 2014 +0200
timesyncd: split privilege dropping code out of timesyncd so that we can make use of it from other daemons too
This is preparation to make networkd work as unpriviliged user.
diff --git a/src/shared/capability.c b/src/shared/capability.c
index b49c514..69e054b 100644
--- a/src/shared/capability.c
+++ b/src/shared/capability.c
@@ -29,12 +29,13 @@
#include <ctype.h>
#include <sys/capability.h>
#include <sys/prctl.h>
+#include "grp.h"
#include "macro.h"
-#include "capability.h"
#include "util.h"
#include "log.h"
#include "fileio.h"
+#include "capability.h"
int have_effective_cap(int value) {
_cleanup_cap_free_ cap_t cap;
@@ -212,3 +213,71 @@ int capability_bounding_set_drop_usermode(uint64_t drop) {
return r;
}
+
+int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilites) {
+
+ _cleanup_cap_free_ cap_t d = NULL;
+ cap_value_t bits[sizeof(keep_capabilites)*8];
+ unsigned i, j = 0;
+ int r;
+
+ /* Unfortunately we cannot leave privilege dropping to PID 1
+ * here, since we want to run as user but want to keep some
+ * capabilities. Since file capabilities have been introduced
+ * this cannot be done across exec() anymore, unless our
+ * binary has the capability configured in the file system,
+ * which we want to avoid. */
+
+ if (setresgid(gid, gid, gid) < 0) {
+ log_error("Failed change group ID: %m");
+ return -errno;
+ }
+
+ if (setgroups(0, NULL) < 0) {
+ log_error("Failed to drop auxiliary groups list: %m");
+ return -errno;
+ }
+
+ if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
+ log_error("Failed to enable keep capabilities flag: %m");
+ return -errno;
+ }
+
+ r = setresuid(uid, uid, uid);
+ if (r < 0) {
+ log_error("Failed change user ID: %m");
+ return -errno;
+ }
+
+ if (prctl(PR_SET_KEEPCAPS, 0) < 0) {
+ log_error("Failed to disable keep capabilities flag: %m");
+ return -errno;
+ }
+
+ r = capability_bounding_set_drop(~keep_capabilites, true);
+ if (r < 0) {
+ log_error("Failed to drop capabilities: %s", strerror(-r));
+ return r;
+ }
+
+ d = cap_init();
+ if (!d)
+ return log_oom();
+
+ for (i = 0; i < sizeof(keep_capabilites)*8; i++)
+ if (keep_capabilites & (1ULL << i))
+ bits[j++] = i;
+
+ if (cap_set_flag(d, CAP_EFFECTIVE, j, bits, CAP_SET) < 0 ||
+ cap_set_flag(d, CAP_PERMITTED, j, bits, CAP_SET) < 0) {
+ log_error("Failed to enable capabilities bits: %m");
+ return -errno;
+ }
+
+ if (cap_set_proc(d) < 0) {
+ log_error("Failed to increase capabilities: %m");
+ return -errno;
+ }
+
+ return 0;
+}
diff --git a/src/shared/capability.h b/src/shared/capability.h
index 64f8641..3e6d999 100644
--- a/src/shared/capability.h
+++ b/src/shared/capability.h
@@ -32,6 +32,8 @@ int have_effective_cap(int value);
int capability_bounding_set_drop(uint64_t drop, bool right_now);
int capability_bounding_set_drop_usermode(uint64_t drop);
+int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilites);
+
DEFINE_TRIVIAL_CLEANUP_FUNC(cap_t, cap_free);
#define _cleanup_cap_free_ _cleanup_(cap_freep)
diff --git a/src/shared/util.c b/src/shared/util.c
index 17b0ae1..4a3e35f 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -6480,8 +6480,7 @@ void hexdump(FILE *f, const void *p, size_t s) {
}
}
-int update_reboot_param_file(const char *param)
-{
+int update_reboot_param_file(const char *param) {
int r = 0;
if (param) {
diff --git a/src/timesync/timesyncd.c b/src/timesync/timesyncd.c
index a56bbc3..27f6b2d 100644
--- a/src/timesync/timesyncd.c
+++ b/src/timesync/timesyncd.c
@@ -1196,72 +1196,6 @@ static int manager_network_monitor_listen(Manager *m) {
return 0;
}
-static int drop_privileges(uid_t uid, gid_t gid) {
-
- static const cap_value_t bits[] = {
- CAP_SYS_TIME,
- };
-
- _cleanup_cap_free_ cap_t d = NULL;
- int r;
-
- /* Unfortunately we cannot leave privilege dropping to PID 1
- * here, since we want to run as user but want to keep te
- * CAP_SYS_TIME capability. Since file capabilities have been
- * introduced this cannot be done across exec() anymore,
- * unless our binary has the capability configured in the file
- * system, which we want to avoid. */
-
- if (setresgid(gid, gid, gid) < 0) {
- log_error("Failed change group ID: %m");
- return -errno;
- }
-
- if (setgroups(0, NULL) < 0) {
- log_error("Failed to drop auxiliary groups list: %m");
- return -errno;
- }
-
- if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
- log_error("Failed to enable keep capabilities flag: %m");
- return -errno;
- }
-
- r = setresuid(uid, uid, uid);
- if (r < 0) {
- log_error("Failed change user ID: %m");
- return -errno;
- }
-
- if (prctl(PR_SET_KEEPCAPS, 0) < 0) {
- log_error("Failed to disable keep capabilities flag: %m");
- return -errno;
- }
-
- r = capability_bounding_set_drop(~(1ULL << CAP_SYS_TIME), true);
- if (r < 0) {
- log_error("Failed to drop capabilities: %s", strerror(-r));
- return r;
- }
-
- d = cap_init();
- if (!d)
- return log_oom();
-
- if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
- cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
- log_error("Failed to enable capabilities bits: %m");
- return -errno;
- }
-
- if (cap_set_proc(d) < 0) {
- log_error("Failed to increase capabilities: %m");
- return -errno;
- }
-
- return 0;
-}
-
int main(int argc, char *argv[]) {
const char *user = "systemd-timesync";
_cleanup_manager_free_ Manager *m = NULL;
@@ -1291,7 +1225,7 @@ int main(int argc, char *argv[]) {
if (r < 0)
goto out;
- r = drop_privileges(uid, gid);
+ r = drop_privileges(uid, gid, (1ULL << CAP_SYS_TIME));
if (r < 0)
goto out;
More information about the systemd-commits
mailing list